3D printed monoliths: From powder to an efficient catalyst for antibiotic degradation

To improve the effectiveness and durability of wastewater treatment technologies, researchers are showing a growing interest in 3D printing technology. This technology has attracted significant interest owing to its ability to fabricate challenging complex geometries using different material compositions. This manuscript is focused on the development of 3D monoliths from noncommercial filaments, i.e., a powder blend of iron oxide and polylactic acid (PLA) at 15 wt% of the former. Different monolith designs have been prepared to improve the fluid dynamics of the process, so a simple cylinder (15-Fe3O4@PLA) and a cylinder with double the length and an internal mesh (15-Fe3O4@PLA-DM) were used. These monoliths were characterized by Scanning electron microscopy (SEM), Differential scanning calorimetry (DSC) and Mössbauer spectroscopy, then used for water-based ofloxacin degradation in a continuous down-up flow configuration. Additionally, computational fluid dynamics simulations were performed to estimate the degradation rate constants and analyze the distribution of fluid velocity and pollutant concentration along the 15-Fe3O4@PLA-reactor. The oxidant dose was also optimized to develop the highest degradation rate. The degradation of the target pollutant for those monoliths was 55 and 82 % under optimized conditions. In addition, the 15-Fe3O4@PLA-DM monolith was operated for long term experiments, keeping the degradation performance at a good 67 % for up to 120 h. Finally a fixed-bed reactor was mounted with printed pellets of the mixture (15:85), Fe3O4:PLA, after being ground in a range of 125-200 μm. Under this setup configuration, we observed the total degradation of ofloxacin. 3D printing technology is cheap, reproducible and time saving in the development of supported catalysts in comparison with conventional deposition techniques. Moreover, the leaching of active sites on streams was largely diminished. In fact under continuous operation the leached Fe concentration is below 0.1 ppm, corroborating the good adhesion of the catalyst in the PLA support.

The social value of a PASI 90 or PASI 100 response in patients with moderate-to-severe plaque psoriasis in Spain

Introduction

Psoriasis is a chronic disease involving the skin, which significantly impacts the quality of life. Disease severity and treatment efficacy (i.e., response) are assessed through the Psoriasis Area and Severity Index (PASI). A PASI 75 response, i.e., an improvement of at least 75% with respect to the baseline PASI score, has traditionally been used as a therapeutic benchmark in clinical trials. Therapeutic advances have made PASI 90 or PASI 100 responses possible in most patients treated with some biologics. A greater response may generate social value beyond clinical outcomes that would benefit both patients and society.

Methods

A 1-year economic model was applied to estimate the impact of having a PASI 75, PASI 90, or PASI 100 response in four areas of analysis (quality of life, activities of daily living, work productivity, and out-of-pocket expenditures) and the social value of having a PASI 90 or PASI 100 response in comparison with a PASI 75 response. A mixed-methods approach based on the scientific literature, a focus group with patient, and an advisory committee with psoriasis stakeholders was used. The model included three different scenarios: having a PASI 90 vs a PASI 75 response; a PASI 100 vs a PASI 90 response; and a PASI 100 vs a PASI 75 response. A sensitivity analysis was included.

Results

The annual economic impact per patient with moderate-to-severe plaque psoriasis having a PASI 75 response was estimated at Ł 6,139, mainly related to labour productivity losses and quality of life reductions. Having a PASI 90 or a PASI 100 response would reduce this impact to €3,956 or €1,353, respectively. Accordingly, the social value of having a PASI 90 instead of a PASI 75 response was estimated at €2,183, and €4,786 with a PASI 100 response.

Discussion

A PASI 90 or PASI 100 response would have a lower economic impact and a greater social value than a PASI 75 response for patients with moderate-to-severe plaque psoriasis.

Assessing the value contribution of bimekizumab for the treatment of moderate-to-severe psoriasis using a multidisciplinary reflective multi-criteria decision analysis

BACKGROUND

Multi-criteria decision analysis (MCDA) was proposed to surmount arbitrary clinical decisions in the field of biological therapies for psoriatic patients. At the same time, MCDA may further highlight the potential of bimekizumab for the treatment of moderate-to-severe psoriasis, compared to placebo, adalimumab, ustekinumab, secukinumab, and even ixekizumab and risankizumab.

RESEARCH DESIGN AND METHODS

The EVIDEM framework was adapted to reflect relevant criteria for the assessment. Estimated values were obtained by means of an additive linear model combining weights and scores assigned by a multidisciplinary committee of 12 experts. Consistency and replicability were evaluated through an alternative weighting method and a re-test.

RESULTS

Bimekizumab was assessed by the committee as an intervention with a positive value contribution for the treatment of moderate-to-severe psoriasis in comparison to any of the alternatives. The drug provides a substantial therapeutical benefits and improves the health results reported by the patients, as it combines a higher level of clearance, rapidity, and persistence with a similar safety and tolerability profile.

CONCLUSIONS

Under a methodology with increasing use in the health field, bimekizumab was evaluated as a drug with a high added value for the treatment of moderate-to-severe psoriasis when compared to six different alternatives.

Unmet Needs in the Management of Moderate-to-Severe Psoriasis in Spain: A Multidimensional Evaluation

Psoriasis is a chronic, systemic inflammatory disease that affects the skin, with a high impact on patients’ quality of life. The aim of this study was to identify and determine the relative importance of unmet needs in the management of moderate-to-severe psoriasis in Spain, from a multi-stakeholder perspective. A mixed method-approach was used to collect information, design a questionnaire and a discrete-choice exercise, and elicit the unmet needs through a multidisciplinary committee composed of 12 experts. A total of 65 unmet needs were identified and categorized into 4 areas: clinical, patient-related, decision-making process, and social. Decision-making process unmet needs were perceived as the most pressing ones, followed by social, clinical and patient-related. Individually, the need to incorporate outcomes that are important to the patients and to have treatments that achieve total clearance with a rapid onset of action and long-term persistence were the most important unmet needs.

Osteoporotic patients treated with bisphosphonates do not show the increased mortality observed in those untreated

INTRODUCTION

Osteoporosis has been said to be associated with increased mortality. On the other hand, it is debated whether treatment with bisphosphonates may reduce mortality in osteoporotic patients. To contribute to the clarification of these issues, we have studied in a prospective cohort the mortality in people without osteoporosis and in patients with osteoporosis, untreated or treated with bisphosphonates MATERIAL AND METHODS: At their inclusion in the cohort, four groups of participants were identified: (a) people without osteoporosis (group 1); (b) osteoporotic patients treated with bisphosphonates (group 2); (c) osteoporotic patients who refused to be treated (group 3); and (d) patients who met osteoporosis diagnostic criteria but were not treated because their risk of fracture was considered to be low (group 4). To compare all four groups, unadjusted Kaplan-Meier estimates of survivorship were obtained and they were compared using log-rank test. Hazard ratios were then estimated via Cox regression adjusting for the main confounders. A comparison among the osteoporotic groups was made by means of a Cox regression analysis performed using only these three groups, adjusting for propensity scores.

RESULTS

Two thousand six hundred and sixty-five people were included. In the unadjusted analysis, mortality in group 3 was higher than in the other groups (p < 0.001). Taking group 1 as a reference, Cox regression analysis showed the following mortality HRs for groups 2, 3, and 4 after adjusting for confounding factors: 0.82 (0.41-1.63), 1.37 (0.90-2.10), and 0.69 (0.46-1.02). In the analysis of the osteoporotic groups with the PS generated for them, and taking group 2 as a reference, the HRs were as follows: group 3, 2.38 (1.34-4.22); group 4, 1.45 (0.61-3.43).

CONCLUSION

Mortality in osteoporotic patients who refused treatment is higher than in osteoporotic patients treated with bisphosphonates. In unadjusted analysis, it was also higher than in non-osteoporotic people; however, this difference disappeared after adjustment for confounding factors.

Vertebral fractures are increased in rheumatoid arthritis despite recent therapeutic advances: a case-control study

Prevalence and risk factors of vertebral fractures in postmenopausal RA women were assessed in 323 patients and compared with 660 age-matched women. Of patients, 24.15% had at least one vertebral fracture vs.16.06% of controls. Age, glucocorticoids and falls were the main fracture risks. Vertebral fractures were associated with disease severity.

INTRODUCTION

There is little quality data on the updated prevalence of fractures in rheumatoid arthritis (RA) that may have changed due to advances in the therapeutic strategy in recent years. This study was aimed at analysing the prevalence and risk factors of vertebral fractures in postmenopausal women with RA and comparing it with that of the general population.

METHODS

We included 323 postmenopausal women diagnosed with RA from 19 Spanish Rheumatology Departments, randomly selected and recruited in 2018. Lateral radiographs of the thoracic and lumbar spine were obtained to evaluate morphometric vertebral fractures and the spinal deformity index. We analysed subject characteristics, factors related to RA, and fracture risk factors. The control group consisted of 660 age-matched Spanish postmenopausal women from the population-based Camargo cohort.

RESULTS

Seventy-eight (24.15%) RA patients had at least one vertebral fracture. RA patients had increased fracture risk compared with controls (106 of 660, 16.06%) (p = 0.02). Logistic regression analysis showed that age (OR 2.17; 95% CI 1.27-4.00), glucocorticoids (OR 3.83; 95% CI 1.32-14.09) and falls (OR 3.57; 95% CI 1.91-6.86) were the independent predictors of vertebral fractures in RA patients. The subgroup with vertebral fractures had higher disease activity (DAS28: 3.15 vs. 2.78, p = 0.038) and disability (HAQ: 0.96 vs. 0.63, p = 0.049), as compared with those without vertebral fractures.

CONCLUSION

The risk of vertebral fracture in RA is still high in recent years, when compared with the general population. The key determinants of fracture risk are age, glucocorticoids and falls. Patients with vertebral fractures have a more severe RA.

Profile of patients who consult with internists for an osteoporosis assessment: The OSTEOMED registry

BACKGROUND AND OBJECTIVES

Osteoporosis is considered a generalised skeletal disorder in which there is impaired bone resistance, which predisposes the individual to a greater risk of fracture. The aim of this cross-sectional study was to collect and present data on the main clinical characteristics of patients who consult medical internists in Spain. Understanding these characteristics can help in implementing action plans to improve these patients' care more effectively and efficiently.

MATERIAL AND METHODS

Through an analysis of the Osteoporosis in Internal Medicine (OSTEOMED) registry, this study presents the main clinical characteristics of patients with osteoporosis who attended internal medicine consultations in 23 Spanish hospital centres between 2012 and 2017. We analysed the reasons for the consultations, the densitometric values, the presence of comorbidities, the prescribed treatment and other lifestyle-related factors.

RESULTS

In total, 2024 patients with osteoporosis were assessed (89.87% women, 10.13% men). The patients' mean age was 64.1±12.1 years (women, 64.7±11.5 years; men, 61.2±14.2 years). There was no significant difference between the sexes in their history of recent falls (9.1% and 6.7%); however, there were significant differences in the daily intake of calcium from milk products (553.8±332.6mg for women vs. 450.2±303.3mg for men; p<.001) and in the secondary causes of osteoporosis (13% of men vs. 6.5% of women; p<.001). In the sample, there were 404 fractures (20%), with a notable number of confirmed vertebral fractures (17.2%, 35.6% in men vs. 15.2% in women; p<.001). A large portion of the patients did not undergo the indicated treatment and presented low levels of physical activity and sun exposure. A significant percentage of the patients presented associated comorbidities, the most common of which were hypertension (32%) and dyslipidaemia (28%).

CONCLUSIONS

These results define the profile of patients with osteoporosis who attend internal medicine consultations in Spain. The results also show the multisystemic character of this condition, which, along with its high prevalence, determine that the specific internal medicine consultations dedicated to managing the condition are the appropriate place for caring for these patients.

Profile of patients who visit medical internists for an osteoporosis assessment: The OSTEOMED registry

BACKGROUND AND OBJECTIVES

Osteoporosis is considered a generalised skeletal disorder in which there is impaired bone resistance, which predisposes the individual to a greater risk of fracture. The aim of this cross-sectional study was to collect and present data on the main clinical characteristics of patients who consult medical internists in Spain. Understanding these characteristics can help in implementing action plans to improve these patients' care more effectively and efficiently.

MATERIAL AND METHODS

Through an analysis of the Osteoporosis in Internal Medicine (OSTEOMED) registry, this study presents the main clinical characteristics of patients with osteoporosis who attended internal medicine consultations in 23 Spanish hospital centres between 2012 and 2017. We analysed the reasons for the consultations, the densitometric values, the presence of comorbidities, the prescribed treatment and other lifestyle-related factors.

RESULTS

In total, 2024 patients with osteoporosis were assessed (89.87% women, 10.13% men). The patients' mean age was 64.1±12.1 years (women, 64.7±11.5 years; men, 61.2±14.2 years). There was no significant difference between the sexes in their history of recent falls (9.1% and 6.7%); however, there were significant differences in the daily intake of calcium from milk products (553.8±332.6mg for women vs. 450.2±303.3mg for men; P<.001) and in the secondary causes of osteoporosis (13% of men vs. 6.5% of women; P<.001). In the sample, there were 404 fractures (20%), with a notable number of confirmed vertebral fractures (17.2%, 35.6% in men vs. 15.2% in women; P<.001). A large portion of the patients did not undergo the indicated treatment and presented low levels of physical activity and sun exposure. A significant percentage of the patients presented associated comorbidities, the most common of which were hypertension (32%) and dyslipidaemia (28%).

CONCLUSIONS

These results define the profile of patients with osteoporosis who attend internal medicine consultations in Spain. The results also show the multisystemic character of this condition, which, along with its high prevalence, determine that the specific internal medicine consultations dedicated to managing the condition are the appropriate place for caring for these patients.

Serum 25-hydroxyvitamin D, parathyroid hormone, calcium intake, and bone mineral density in Spanish adults

Vitamin D insufficiency is very common among Spanish community-dwelling adult subjects. A threshold of serum 25(OH)D around 30 ng/ml would be necessary for the prevention of secondary hyperparathyroidism and hip bone loss in our population, regardless of the dairy calcium ingestion.

INTRODUCTION

This study aims to assess 25-hydroxyvitamin D-25(OH)D-status in Spanish adult subjects and to analyze its relationships with serum PTH levels, calcium intake, and bone mineral density (BMD).

METHODS

A total of 1811 individuals (1154 postmenopausal women and 657 men) aged 44-93 years participated in the study. Serum 25(OH)D, intact parathyroid hormone (PTH), aminoterminal propeptide of type I collagen (P1NP), and C-terminal telopeptide of type I collagen (β-CTX) levels were measured by electrochemiluminescence. BMD was determined by dual x-ray absorptiometry (DXA) at lumbar spine, femoral neck, and total hip.

RESULTS

Serum 25(OH)D levels were below 10, 20, and 30 ng/ml in 5, 40, and 83 % of participants, respectively. There was a significant seasonal difference in mean serum 25(OH)D, with higher levels in summer-autumn. In multivariate analysis, 25(OH)D levels were negatively correlated with age, serum PTH and creatinine, body mass index, smoking, alcohol intake, and a number of chronic diseases, but positively with dairy calcium intake. The magnitude of the difference in serum PTH according to 25(OH)D quartiles was not influenced by calcium intake. A threshold of serum 25(OH)D around 30 ng/ml was observed for serum PTH and hip BMD.

CONCLUSIONS

Vitamin D insufficiency is very common among Spanish community-dwelling adult subjects. A threshold of serum 25(OH)D around 30 ng/ml would be necessary for the prevention of secondary hyperparathyroidism and hip bone loss in our population, regardless of the dairy calcium ingestion. Programs to improve vitamin D status may be required in our country.

Clinical practice guidelines for posmenopausal, glucocorticoid-induced and male osteoporosis. Spanish Society for Research on Bone and Mineral Metabolism (3rd updated version 2014)

These guidelines update issues covered in previous versions and introduce new ones that have arisen in recent years. The former refer mainly to the therapeutic developments that have been made during this time (zoledronate, denosumab, bazedoxifene), which have led to a change in the drug selection algorithm. The latter deal with therapeutic management, the description of new adverse effects (which have led to changes in therapeutic behaviour patterns, as is the case with atypical fracture of the femur), treatment duration (with consideration for the so-called "therapeutic holidays"), the so-called sequential treatment and changes in treatment imposed by certain circumstances. A new algorithm has been introduced for sequential treatment. Attention has also been paid to vertebroplasty and kyphoplasty.

Serum uric acid is associated with quantitative ultrasound parameters in men: data from the Camargo cohort

This study analyzes the association between serum uric acid levels and heel quantitative ultrasound (QUS) parameters in men aged 50 or more from the Camargo cohort. We found that higher serum uric acid levels are positively associated with all QUS measurements, suggesting a better bone quality in men with elevated serum uric acid values.

INTRODUCTION

Higher serum uric acid concentrations have been associated with higher bone mineral density and lower prevalence of fractures. However, there are no studies that have assessed the bone quality properties in Caucasians. Therefore, we have analyzed the association between quantitative ultrasound (QUS) and serum uric acid levels in adult men from a population-based cohort.

METHODS

A total of 868 men older than 50 were recruited from a larger cohort (Camargo Cohort) after excluding those with any known condition or drug treatment with a possible influence on bone metabolism, or those with a previous diagnosis of gout or taking hipouricemic agents. Bone turnover markers (PINP and CTX), 25OH-vitamin D and PTH levels were measured by electrochemiluminiscence. BMD was determined by DXA, and heel QUS with a gel-coupled device.

RESULTS

Lumbar, femoral neck and total hip BMD was significantly higher in men with higher serum uric acid levels. QUS parameters were also significantly higher in men with high uric acid levels than those with lower values, and increased continuously across quartiles after adjustment for confounding variables. In multiple regression analysis, serum uric acid was significantly associated with all QUS parameters. Finally, men with serum acid levels above median showed higher values in all the QUS parameters than men with lower values.

CONCLUSIONS

Higher serum uric acid levels in men older than 50 years are positively associated with QUS parameters. These data might suggest a better bone quality in men with elevated serum uric acid values.

Bone mass and vitamin D levels in women with a diagnosis of fibromyalgia

No differences in either bone mineral density or serum 25OHD levels have been found between 205 women with fibromyalgia (both pre- and postmenopausal) and their controls. However, a lack of the expected 25OHD summer rise was observed in patients.

INTRODUCTION

Contradictory data have been published regarding a possible association between fibromyalgia and osteoporosis or hypovitaminosis D. Most studies, however, have been performed in small size samples and have excluded postmenopausal women. We decided to study this association in a larger sample of fibromyalgia patients including both pre- and postmenopausal women.

METHODS

Two hundred five patients were recruited from a clinic specializing in fibromyalgia and 205 healthy controls were enrolled from the census of a Primary Care Center. Controls were matched with patients by age and the time of the year they were included in the study. Bone mineral density (BMD) was measured by DXA. Serum 25OHD, iPTH, P1NP, and CTX were also determined.

RESULTS

BMD was similar in both groups (lumbar spine, 0.971 ± 0.146 g/cm(2) in patients and 0.970 ± 0.132 g/cm(2) in controls; femoral neck, 0.780 ± 0.122 g/cm(2) and 0.785 ± 0.117 g/cm(2), respectively). 25OHD levels were also similar: 23.0 ± 9.5 ng/ml and 24.1 ± 9.6 ng/ml. However, while controls showed the usual summer rise in 25OHD, fibromyalgia patients did not. PTH did not show seasonal changes, but on average was higher in patients (51 pg/ml vs. 48 pg/ml; p = 0.034). P1NP or CTX were similar in both groups.

CONCLUSIONS

No differences in BMD were found between patients and controls. As for 25OHD, a lack of its expected summer rise was observed. It is doubtful whether this has any homeostatic consequence. We consider that the association reported in other studies is merely circumstantial, and not due to the intrinsic characteristics of these disorders.

Missense polymorphisms of the WNT16 gene are associated with bone mass, hip geometry and fractures

Two missense polymorphisms of WNT16 were associated with hip bone mineral density (BMD), the buckling ratio of the femoral neck, calcaneal ultrasound and hip fractures in individuals under 80 years of age. These results confirm the association of the WNT16 gene with bone mass and osteoporotic fractures.

INTRODUCTION

Osteoporosis has a strong genetic component. Wnt ligands stimulate the differentiation of osteoblast precursors and play a major role in skeletal homeostasis. Therefore, the aim of this study was to explore the association of allelic variants of the WNT16 gene with BMD, other structural parameters of bone and osteoporotic hip fractures.

METHODS

Six single nucleotide polymorphisms were analysed in 1,083 Caucasian individuals over 49 years of age.

RESULTS

Two missense polymorphisms (rs2908004 and rs2707466) were associated with femoral neck BMD, with average differences across genotypes of 35 mg/cm(2) (p = 0.00037 and 0.0015, respectively). Likewise, the polymorphisms were associated with calcaneal quantitative ultrasound parameters (p = 0.00004 and 0.0014, respectively) and the buckling ratio, an index of cortical instability of the femoral neck (p = 0.0007 and 0.0029, respectively). Although there were no significant differences in the genotype frequency distributions between 294 patients with hip fractures and 670 controls, among the subgroup under 80 years of age, TT genotypes were underrepresented in patients with fractures (odds ratio 0.50; CI 0.27-0.94).

CONCLUSION

Common missense polymorphisms of the WNT16 gene are associated with BMD at the hip, calcaneal ultrasound and the buckling ratio of the femoral neck, as well as with hip fractures in individuals under 80 years of age. Overall, these results confirm the association of the WNT16 locus with BMD identified in genome-wide association studies and support its role in determining the risk of osteoporotic fractures.

Association of ACACB polymorphisms with obesity and diabetes

Acetyl-CoA carboxylase beta, encoded by the ACAB gene, plays an important role in the oxidation of fatty acids. The aim of this study was to check the hypothesis that allelic variants of ACACB influence the risk of obesity and type 2 diabetes mellitus. Twenty five tagging single nucleotide polymorphisms (SNPs) capturing common variants of the ACACB gene were selected and analyzed in two cohorts including 1695 postmenopausal women of the general population and in 161 women with severe obesity (BMI>35). In vitro binding of transcription factors was explored by electrophoretic mobility shift assays (EMSA). T alleles at the rs2268388 locus were overrepresented in women with severe obesity (18% vs. 10% in controls; OR 1.74 [95% confidence interval 1.30-2.47]), which was statistically significant after multiple-test adjustment (p=0.0004). Likewise, T alleles at the rs2268388 locus and C alleles at the rs2239607 locus were associated with diabetes, in the discovery as well as in the replication cohorts, even after women with severe obesity were excluded (OR 3.6 and 2.8, for TT and CC homozygotes, respectively). Allelic differences in the binding affinity for nuclear proteins were revealed in vitro by EMSA and competition experiments were consistent with the binding of glucorticoid receptor and serum response factor. In conclusion, common polymorphisms of ACACB gene are associated with obesity and, independently, with type 2 diabetes in postmenopausal women, suggesting that the activity of acetyl-CoA carboxylase beta plays an important role in these disorders related to energy metabolism.

Metabolic syndrome, fractures and gender

The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors which has been suggested to have a possible effect on bone mass. Somewhat paradoxically, it is not clear whether this effect is protective or detrimental. Some of its components (e.g., obesity) seem to have the first type of effect and others (e.g., glucose metabolism changes) the second one. The epidemiological studies are not conclusive. Five out of six cross-sectional studies show no differences in the rate of fractures between subjects with or without MetS. In the sixth, fewer fractures were observed in patients with the syndrome. Two of three prospective studies also found fewer fractures, but the third more. Regarding the relationship of each individual component of MetS with fractures, the results - apart from obesity - are scarce or inconsistent. The relationship between MetS and bone mineral density (BMD) or bone turnover markers (BTMs) has also been addressed. Without adjusting for BMI, six out of nine studies have shown higher BMD values in MetS patients and the rest no differences. This positive effect on BMD is mainly driven by BMI, and therefore disappears after adjusting for it. The fasting plasma glucose level has been shown in general to be positively associated with BMD. Hypertension and hypertriglyceridemia showed variable results, while BTMs are decreased in MetS. Finally, there is no definite evidence about the existence of gender differences in the effect of MetS on bone. In conclusion, MetS tends to be positively associated with BMD and negatively with BTMs. No clear-cut data about fractures are available.

Association of aromatase and estrogen receptor gene polymorphisms with hip fractures

Two polymorphisms of the aromatase and estrogen receptor genes appeared to interact to influence the risk of hip fractures in women.

INTRODUCTION

Allelic variants of the aromatase gene have been associated with bone mineral density and vertebral fractures. Our objective was to analyze the relationship between two polymorphisms of the aromatase and estrogen receptor genes and hip fractures.

METHODS

We studied 498 women with hip fractures and 356 controls. A C/G polymorphism of the aromatase gene and a T/C polymorphism of the estrogen receptor alpha gene were analyzed using Taqman assays. Aromatase gene expression was determined in 43 femoral neck samples by real-time RT-PCR.

RESULTS

There were no significant differences in the overall distribution of genotypes between the fracture and control groups. However, among women with a TT genotype of the estrogen receptor, the CC aromatase genotype was more frequent in women with fractures than in controls (39 vs. 23%, p = 0.009). Thus, women homozygous for T alleles of estrogen receptor and C alleles of aromatase were at increased risk of fracture (odds ratio 2.0; 95% confidence interval 1.2-3.4). The aromatase polymorphism was associated with RNA levels in bone tissue, which were three times lower in samples with a CC genotype (p = 0.009).

CONCLUSIONS

These common polymorphisms of the aromatase and estrogen receptor genes appear to interact, influencing the risk of hip fractures in women.

[Risk indicators of preventable morbidity related to drug utilization]

OBJECTIVE

To select clinical situations that can be used as risk indicators of preventable morbidity caused by drugs at the community pharmacies, and to study their acceptability, in terms of pertinence and relevance.

METHODS

We used the Delphi technique, in 2 rounds, by a panel of 14 medical doctors and pharmacists experts, to study the relevance of 68 types of clinical situations as risk indicators of preventable morbidity related to drug utilization used by health professionals in community pharmacies, with scientific evidence of foreseeable adverse result, frequent situations in ambulatory care and with controllable cause and result.

RESULTS

43 of the 68 indicators were considered usable and pertinent. The indicators referred three areas: drug type (medications of narrow therapeutic margin, with individualized dose and adverse reactions frequent and severe), health problem (chronic problems, especially asthma, cardiac, thyroid and prostate illness, and pain), and patient (old or with several medications. Pharmacists systematically overvalued some indicators in relation to the doctors, but differences were not significant.

CONCLUSIONS

Forty-three indicators were selected as valuable to identify situations of preventable morbidity related to drug utilization.

Osteoprotegerin and bone mass in squamous cell head and neck cancer patients

Osteoprotegerin (OPG) is considered one of the main regulators of bone remodeling. Various patterns of serum OPG levels have been described in different types of tumors. We undertook this study to determine serum OPG levels in patients with squamous cell head and neck cancer (SCHNC), analyzing their relationship with other metabolic bone parameters and bone mineral density (BMD), as well as the possible influence of chemotherapy. Forty male patients with localized SCHNC were studied, and their results were compared with those of 40 healthy male controls. The type of treatment followed by each patient was noted. Age, weight, height, and lifestyle habits were recorded; and OPG, Ca(2+), intact parathyroid hormone (iPTH), 25-Hydroxyvitamin D (25OHD) and 1,25-Dihydroxyvitamin D (1,25(OH)(2)D), bone alkaline phosphatase, osteocalcin, and serum C-terminal cross-links telopeptide of type I collagen (ICTP) were determined. Dual-energy X-ray absorptiometry BMD at the lumbar spine, femoral neck, and hip was also measured. Serum OPG was higher in patients than in controls (91.7 +/- 25.8 vs. 77.2 +/- 26.3, P = 0.02). ICTP (a bone resorption marker) was 37% higher in patients (P = 0.007). Bone mass was lower in patients at the lumbar spine, femoral neck, and total hip. Lumbar spine Z-score showed a significant progressive decrease in controls, stage I-III patients, and stage IV patients. Logistic regression analysis showed a significant association between the disease and serum OPG levels, the odds ratio per standard deviation increase of this being 1.9 (95% confidence interval 1.1-3.8, P = 0.04) after adjusting for bone mass and ICTP serum levels, as well as for alcohol and smoking history. Adjustment for alcohol intake and tobacco use did not cancel out BMD differences between patients and controls. Patients with SCHNC show increased OPG serum levels, increased bone resorption, and decreased bone mass. The OPG rise appears to be unrelated to the BMD decrease, and the BMD decrease seems to be, at least in part, independent of smoking and drinking habits. No differences in either OPG or BMD were seen between patients with and without chemotherapy. Further studies are needed to clarify the mechanisms responsible for OPG and BMD changes in SCHNC.

Factors other than glucocorticoids are involved in the osteoblast activity decrease caused by tissue injury

OBJECTIVE

Serum osteocalcin is a marker of bone formation. The concentration of osteocalcin is decreased with tissue injury. As glucocorticoids are known both to be increased in this situation and to diminish serum osteocalcin, we have hypothesized that they could be involved in this decrease.

DESIGN AND PATIENTS

We compared osteocalcin levels in two groups of patients undergoing abdominal surgery, one receiving thiopental, and the other etomidate, a glucocorticoid synthesis blocker. For comparative reasons, another protein decreased by glucocorticoids (osteoprotegerin) was measured in patients anaesthetized with thiopental.

MEASUREMENTS

Serum osteocalcin, cortisol and albumin were determined before and over the 24 h following surgery. Serum concentration of osteoprotegerin (OPG) and receptor activator of the nuclear factor kappaB ligand (RANKL) were also determined before and 24 h after surgery in a third group of nine patients who received thiopental for anaesthetic induction.

RESULTS

Cortisol levels were increased in the thiopental group, whereas, as expected, were decreased in etomidate patients. However, serum osteocalcin concentration decreased in a similar way in both groups. Serum OPG and RANKL levels were within the normal range at baseline and did not significantly change after surgery.

CONCLUSIONS

The decrease in serum osteocalcin induced by tissue injury is independent of the increase in cortisol secretion triggered by the latter. In addition, another pharmacologically proven effect of cortisol on bone metabolism, OPG inhibition, could not be demonstrated in the first 24 h following surgery, in spite of the physiological increase in endogenous cortisol secretion taking place in this period.

Problemas de salud relacionados con los medicamentos en un servicio de urgencias hospitalario

BACKGROUND AND OBJECTIVE

Medication-related problems (MRPs) are health problems resulting from patient pharmacotherapy failure that interfere with the expected outcome in the patient's health status. The aim of this study was to discover the health problems associated with the appearance of MRPs.

PATIENTS AND METHOD

Patient interviews, together with the assessment of medical records were the sources of information used in the assessment and identification of MRPs. A validated questionnaire was used for the interviews; in order to classify the health problems found, the ICD-9 was used.

RESULTS

2,556 patients were interviewed over a period of one year at a hospital emergency department. 2,261 of these cases were valid. Osteoarticular diseases, poorly defined signs and symptoms of illness, injuries and intoxications were the disorders most commonly associated with the appearance of MRPs. MRPs of necessity and effectiveness had a similar profile. MRPs of safety were more commonly associated with poorly defined signs and symptoms of illness, injuries and intoxications, as well as nervous, digestive and blood problems.

CONCLUSIONS

Most frequent medication related health problems causing visits to hospital emergency departments were osteoarticular disorders, followed by poorly defined signs and symptoms of illness. Differences were observed in the diagnoses between the different dimensions and types of MRP.

[Primary health care and responsibilities of public health in 6 countries of Europe and North America: a pilot study]

BACKGROUND

Rapidly occurring changes within the health care systems are creating an opportunity to re-orient the relationships between their different sectors. In order to know the locus of responsibility for various types of preventive activities, we undertook an inquiry on eight areas in six countries from Europe and North America.

METHODS

An inquiry among experts based on a matrix which arrayed the type of preventive health services against the target population. Eight clinical conditions were identified (childhood immunizations; adult influenza vaccination; mammography screening, tuberculosis screening, hypertension screening. PKU screening, HIV screening, and osteoporosis testing) trying to know their target population and the locus of responsibility for setting of policy, level to contact individuals for testing, follow-up of people with abnormal tests and maintenance of their medical records.

RESULTS

This pilot study showed very little results coincidence either within the eight surveyed areas or across them. There was no regular pattern for the preventive activities studied among the different countries, neither according to the type of health system, nor to the primary health care orientation of the different systems.

CONCLUSIONS

There was a limited consensus in the activities studied concerning the best mode of doing public health interventions for personal health services.

Influence of apolipoprotein E polymorphism on plasma vitamin A and vitamin E levels

BACKGROUND

Plasma concentrations of vitamins A and E are positively correlated with those of concurrent lipids and, on the other hand, lipid levels are influenced by apolipoprotein E polymorphism. Therefore, the effect of this polymorphism on both vitamins was analysed in an adult population.

MATERIALS AND METHODS

Subjects were recruited from a working population. Their anthropometric, lifestyle and dietary intake variables and menopausal status were recorded. Their apolipoprotein E phenotype and their plasma vitamins A and E (by high-performance liquid chromatography) and lipid (enzymatically) concentrations were determined after an overnight fast. The associations of the phenotype with vitamins and lipids were studied in men and women separately and controlling for significant covariates.

RESULTS

The apolipoprotein E phenotype was associated with the concentrations of total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol in women, whereas no associations with lipids were found in men. Vitamin A and vitamin E levels were higher in men than in women, but only the difference in the former persisted after lipid adjustment. Apolipoprotein E2 slightly increased vitamin A levels in women, an effect which was still evident with lipid adjustment. Actually, both the apolipoprotein E phenotype and triglyceride were selected as significant predictors of this vitamin by multiple regression. This phenotype did not affect vitamin E levels in either sex.

CONCLUSIONS

Lipids do not mediate the effect of gender on vitamin A levels. Apolipoprotein E polymorphism is an independent determinant of vitamin A levels in women. Pending confirmation by others, we propose that enhancement of this vitamin may contribute to the beneficial impact of the epsilon2 allele on human ageing and health.

Expression of opioid receptors in osteoblast-like MG-63 cells, and effects of different opioid agonists on alkaline phosphatase and osteocalcin secretion by these cells

We have previously shown that several stressful situations associated with tissue injury determine a decrease in serum osteocalcin concentration. Since reduced osteocalcin production is a marker of decreased osteoblastic activity, this finding could be related to the pathogenesis of osteoporosis secondary to some diseases. Endogenous opioids are involved in stress response. Proenkephalin-derived peptides have been shown to inhibit alkaline phosphatase activity, another marker of bone formation, in the murine cell line ROS-17/2.8. On the other hand, serum osteocalcin has been reported as being low in heroin abusers. We have therefore thought it of interest to study the presence of opioid receptors in the human osteoblast-like cell line MG-63, and to evaluate the effects of different opioid agonists on the secretion of alkaline phosphatase and osteocalcin by these cells. The presence of opioid receptors was studied by means of RT-PCR and immunohistochemistry. RT-PCR studies suggested the presence of specific mRNA for the three types of receptors, and immunohistochemistry clearly showed their occurrence. Osteocalcin synthesis was significantly inhibited by high concentrations of the mu agonists morphine and (D-Ala(2), N-MePhe(4),Gly(5)-ol)-enkephalin although no changes were seen with the delta agonist (D-Ala(2),D-leu(5))-enkephalin. Morphine-induced osteocalcin inhibition was abolished when osteoblastic cells were incubated simultaneously with naloxone, whereas it was potentiated when cells were preincubated with naloxone. None of the opioid agonists modified the secretion of alkaline phosphatase. In conclusion, human osteoblast-like cells MG-63 express the three types of opioid receptors. Endogenous opioids may be involved in the reduction of osteocalcin observed in stressful situations associated with tissue injury.

Apolipoprotein E polymorphism in men and women from a Spanish population: allele frequencies and influence on plasma lipids and apolipoproteins

The apolipoprotein (apo) E phenotype and its influence on plasma lipid and apolipoprotein levels were determined in men and women from a working population of Madrid, Spain. The relative frequencies of alleles epsilon(2), epsilon(3) and epsilon(4) for the study population (n=614) were 0.080, 0.842 and 0.078, respectively. In men, apo E polymorphism was associated with variations in plasma triglyceride and very low-density lipoprotein (VLDL) lipid levels. It was associated with the proportion of apo C-II in VLDL, and explained 5.5% of the variability in the latter parameter. In women apo E polymorphism was associated with the concentrations of plasma cholesterol and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) related variables. The allelic effects were examined taking allele epsilon(3) homozygosity as reference. In men, allele epsilon(2) significantly increased VLDL triglyceride and VLDL cholesterol concentrations, and this was accompanied by an increase of the apo C-II content in these particles. Allele epsilon(4) did not show any significant influence on men's lipoproteins. In women, allele epsilon(2) lowered LDL cholesterol and apo B levels, while allele epsilon(4) increased LDL cholesterol and decreased the concentrations of HDL cholesterol, HDL phospholipid and apo A-I. These effects were essentially maintained after excluding postmenopausal women and oral contraceptive users from the analysis.

IN CONCLUSION

(1) the population of Madrid, similar to other Mediterranean populations, exhibits an underexpression of apo E4 compared to the average prevalence in Caucasians, (2) gender interacts with the effects of apo E polymorphism: in women, it influenced LDL and HDL levels, whereas in men it preferentially affected VLDL, and (3) allele epsilon(2) decreased LDL levels in women, while it increased both VLDL lipid levels and apo C-II content in men, but, in contrast to allele epsilon(4), it did not show an impact on HDL in either sex.

Etidronate inhibits the production of IL-6 by osteoblast-like cells

IL-6 is a resorbing cytokine synthesized by osteoblasts and monocytes that has been implicated in the pathogenesis of osteoporosis. Bisphosphonates are well-known antiresorptive drugs, the antiosteoclastic effect of which has been recently suggested to be brought about at least in part through osteoblasts. Based on these facts, we have studied the effect of etidronate on the production of IL-6 by two tumoral cell lines of human osteoblastic phenotype (MG63 and SaOs cells), and by peripheral blood mononuclear cells (PBMC). For comparison, another antiresorptive drug, estradiol, was included in the study. MG63 cells were stimulated with LPS and IL-1 beta, SaOs cells with LPS, IL-1 beta and PMA, and PBMC with LPS and PMA. Etidronate was tested at 10(-7), 10(-6), 10(-5), and 10(-4) M, and 17beta-estradiol was tested at 10(-10), 10(-9), 10(-8), and 10(-7) M. IL-6 was determined in supernatants by an ELISA. No significant effect of either etidronate or estradiol on IL-6 secretion by LPS or PMA-stimulated PBMC was found. However, in osteoblastic-like cells, an inhibition of IL-6 production by etidronate in LPS-stimulated cultures was found. At the highest concentrations tested, IL-6 production values were 58 +/- 9% and 53 +/- 8% of those at base line for MG63 and SaOs cells, respectively. Estradiol did not modify IL-6 secretion under any condition. In conclusion, our study supports the contention that the antiresorptive effect of bisphosphonates may be due in part to a decrease in IL-6 production by osteoblasts.

Diagnostic approach to patients with suspected pulmonary embolism: a report from the real world

This study was carried out to examine the diagnostic approach to patients with suspected pulmonary embolism (PE) in a university hospital. A retrospective case record review of 251 patients with suspected pulmonary embolism was carried out according to a standard protocol, which looked at the utilisation of imaging techniques and compared clinical diagnoses with a standardised diagnosis established according to current recommendations. Isotopic lung scan was the most commonly used technique (73%), followed by leg vein sonography (36%) and contrast venography (31%). Lung arteriography was done in only 7% of patients. Among the 205 patients with a clinical diagnosis of PE, 115 (56%) would be diagnosed as having PE according to the standard criteria, 84 (41%) would be unclassified, and six (3%) would not be regarded as having PE. Among patients who were diagnosed as having PE and received anticoagulant therapy, 32% did not have the diagnosis confirmed by an imaging technique. Most of these had a non-diagnostic lung scan which, despite evidence to the contrary, seemed to be interpreted as confirmation of PE. We conclude that clinicians do not seem to follow current recommendations when approaching patients with suspected PE. In particular, there is an over-reliance on lung scans, and the significance of non-diagnostic scans was often misinterpreted. Arteriography was underused. These results emphasise the need to take measures to implement practice guidelines and to explore the usefulness of newer non-invasive techniques.

1,25-Dihydroxyvitamin D3 receptors in peripheral blood mononuclear cells from patients with renal insufficiency

A reduced expression of the vitamin D receptor (VDR) in parathyroid glands of uremic animals and humans has been observed. Similar results have been obtained by our own group in peripheral blood mononuclear cells (PBMC) from patients with secondary hyperparathyroidism to chronic renal failure. However, the reasons for these changes are not clear. In the present study, we have investigated the specific uptake of [3H]1,25(OH)2D3 by PBMC of 11 women with advanced chronic renal failure (A-CRF), 6 women with mild-moderate renal insufficiency (M-CRF), and 23 healthy women. The mean dissociation constant (KD) was similar in both groups of patients and in healthy women (A-CRF: 0.7 +/- 0.5 x 10(-10) M; M-CRF: 1.1 +/- 0.9 x 10(-10) M; controls: 1.0 +/- 0.6 x 10(-10) M). However, VDR concentration was significantly decreased in A-CRF (0.8 +/- 0.5 fmol/10(7) cells vs. 2.3 +/- 0.9 fmol/10(7) cells in controls, p < 0.001), whereas no changes were seen in M-CRF (1.7 +/- 0.7 fmol/10(7) cells vs. 2.3 +/- 0.9 fmol/10(7) cells in controls). No correlation was seen between VDR and serum calcitriol or PTH levels, when considering both groups of patients together or separately. Conversely, a significant negative correlation was found between VDR and serum creatinine values when A-CRF and M-CRF were considered altogether (r = -0.63; p < 0.01). Treatment with two different schedules of oral calcitriol (five patients with 0.5 microgram/day for 1 month and four patients with 2 micrograms/day for 7 days) did not change VDR concentrations. We conclude that the low levels of serum 1,25(OH)2D3 of uremia are not responsible for the decrease in VDR concentration found in these patients.

[Agreement in the clinical diagnosis of pulmonary embolism]

BACKGROUND

The diagnosis of pulmonary embolism (PE) may be a difficult task. The diagnostic performance of imaging techniques is limited and pre-test probability of PE, estimated from basic clinical data, must be taken into consideration to interpret their results. The aim of this study was to evaluate the accuracy and agreement of clinicians in estimating PE probability.

PATIENTS AND METHODS

We reviewed the charts of 116 patients admitted to hospital for suspected PE. Basic clinical data (symptoms and signs, arterial blood gases, chest X-ray and EKG) were extracted and given to five clinicians, who were asked to estimate the probability of PE. We determined the inter-clinician agreement and compared their estimates with the final diagnoses.

RESULTS

Among patients with a final diagnosis of PE, clinical estimations of PE probability were: high in 63%, intermediate in 21%, and low in 16%. The accuracy of estimates varied between 67 and 80%. Actual PE prevalence was 81% among cases estimated as having high probability and 42% in those considered as low probability. The global inter-clinician agreement rates ranged from 56 to 72%, whereas the average kappa coefficient was 0.44.

CONCLUSION

Basic clinical data seem to be more useful to predict PE than to exclude it. The accuracy and agreement between estimates from different clinicians are only moderate.

Seasonal deficiency of vitamin D in children: a potential target for osteoporosis-preventing strategies?

Peak bone mass attained after skeletal growth is a major determinant of the risk of developing osteoporosis later in life, hence the importance of nutritional factors that contribute to bone mass gain during infancy and adolescence. An adequate supply of vitamin D is essential for normal bone homeostasis. This study was undertaken to determine what the levels are of 25-hydroxyvitamin D (25(OH)D) that may be considered desirable in children and to assess if normal children maintain these levels throughout the year. Vitamin D metabolites and parathyroid hormone (PTH) serum levels were measured in 21 children in March and October, prior to and after the administration of a daily supplement of 25(OH)D (40 microg for 7 consecutive days). There were inverse correlations between basal 25(OH)D levels and supplementation-induced changes in serum 1,25(OH)2D (r = 0.57, p < 0.05) and PTH (r = 0.41, p < 0.05). When basal levels of 25(OH)D were below 20 ng/ml, the supplement induced an increase in serum 1,25(OH)2D; with basal 25(OH)D under 10-12 ng/ml, the supplement also decreased serum PTH. The lowest serum level of 25(OH)D in 43 normal children studied in summer was 13 ng/ml. Those results suggested that the lowest limit for desirable levels of 25(OH)D in children was somewhere between 12 and 20 ng/ml. However, 31% of 51 normal children studied in winter had levels below 12 ng/ml, and 80% had levels lower than 20 ng/ml. Those children are likely to have suboptimal bioavailability of vitamin D, which might hamper their achievement of an adequate peak bone mass. Since cutaneous synthesis of vitamin D is rather limited in winter, oral vitamin D supplementation should be considered.

[McArdle's disease in adults: clinical and genetic study]

McArdle's disease is a rare metabolic myopathy resulting from an absence of functional muscle glycogen phosphorylase that is inherited as an autosomal recessive condition. Recent molecular genetic studies have identified more than ten different mutations in patients with McArdle's disease, although a nonsense point mutation at codon 49 in exon 1 (R49X) accounts for approximately 85% of mutant alleles in American and British patients. We describe clinical, biochemical and genetic characteristics of five adults patients with McArdle's disease studied at our hospital during the last 10 years.

Bronchiolitis obliterans and IgA nephropathy. A new cause of pulmonary-renal syndrome

IgA nephropathy is a common form of glomerulonephritis, classically manifested by asymptomatic hematuria. Although the exact pathophysiologic mechanism is still unknown, renal damage has been related to mesangial deposition of IgA-containing immune complexes. In recent years, some lung diseases have been associated with IgA nephropathy, including pulmonary hemorrhage and sarcoidosis. We report a patient with idiopathic bronchiolitis obliterans who developed a rapidly progressive glomerulonephritis due to IgA deposits. Extensive deposits of IgA were also found in the lungs, thus suggesting a pathogenetic role for IgA in tissue injury at both organ levels. To our knowledge this association has not been previously described in the literature.

Expression and functional role of nitric oxide synthase in osteoblast-like cells

Nitric oxide synthases (NOS) are enzymes that produce nitric oxide (NO) from L-arginine in a reaction yielding citrulline as a coproduct. Nitric oxide modulates the activity of a wide variety of cells, but little is known about its effects on bone cells. In the present study we report that the NOS inhibitor NG-monomethyl-L-arginine (NMMA) induced a dose-dependent inhibitory effect on the proliferation of the osteoblast-like cell lines MG63 and ROS 17/2.8. The inhibitory effect was prevented by increasing L-arginine concentrations in the medium and by the NO donor sodium nitroprusside. Likewise, NMMA inhibited interleukin-6 secretion, independently of its effect on cell number. NOS expression by MG63 cells was confirmed by measuring their ability to metabolize radiolabeled L-arginine to citrulline. NOS bioactivity was detected in unstimulated cells, but was markedly increased by stimulating the cells with cytokines, lipopolysaccharide, or 1,25-dihydroxyvitamin D3. NOS activity was partially dependent upon the presence of calcium in the medium. Furthermore, constitutive-type NOS (c-NOS) and inducible-type NOS (i-NOS) mRNA expression was detected in ROS 17/2.8 cells after reverse transcription and polymerase chain reaction amplification. In conclusion, osteoblast-like cells express c-NOS and i-NOS, and NOS activity seems to play an important role in the regulation of cell proliferation and function.

Interleukin-4 as a bone regulatory factor: effects on murine osteoblast-like cells

Bone remodelling is regulated at the local level by an incompletely elucidated cytokine network. In the present study we have determined the effect of interleukin-4 (IL-4), a cytokine produced by T lymphocytes and other cells, on the activity of murine osteoblasts. IL-4 (0.1-10 ng/ml) did not influence the proliferation rate of the osteoblast-like cell line MC3T3, but inhibited the expression of alkaline phosphatase. In long-term cultures supplemented with ascorbic acid and glycerophosphate such an effect was accompanied by a retardation of matrix mineralization. IL-4 also stimulated M-CSF expression by MC3T3 cells, both at the RNA and bioactivity levels. However, no stimulation of IL-1, IL-6, GM-CSF or PGE2 production was observed. An IL-4-induced inhibition of alkaline phosphatase expression and retardation of mineralization was also found in cultures of primary osteoblast-like cells isolated from neonatal mice calvariae. These results suggest that IL-4, probably released by cells within the bone marrow, may locally influence the activity of bone-forming cells.

1,25-Dihydroxyvitamin D3 receptors in peripheral blood mononuclear cells from patients with primary and secondary hyperparathyroidism

A decreased number of calcitriol (1,25(OH)2D3) receptors has been observed in parathyroid glands of uremic animals. In humans, studies carried out in surgically removed parathyroid glands have shown that calcitriol binding is higher in primary than in secondary hyperparathyroidism. Since specific receptors for calcitriol have been described in peripheral blood mononuclear cells (PBMC), we have investigated the specific uptake of 3H-labelled 1,25(OH)2D3 in PBMC of 12 women with primary hyperparathyroidism (PHP), 8 women with hyperparathyroidism secondary to chronic renal failure (SH), 9 women with renal transplant (RT), and 23 healthy women. The median dissociation constant (Kd) was similar in all three groups of patients and in healthy women (mean +/- S.D. (range): PHP, 1.2 +/- 1.0 (0.2-4) x 10(-10) M; SH, 0.6 +/- 0.4 (0.2-1.2) x 10(-10) M; RT, 1.1 +/- 0.5 (0.4-1.9) x 10(-10) M; controls, 1.0 +/- 0.6 (0.3-2.6) x 10(-10) M). However, the maximal binding capacity (Nmax) was significantly enhanced in PHP (3.9 +/- 1.9 (1.3-7.6) fmol/10(7) cells vs. 2.3 +/- 0.9 (1.1-4.4) fmol/10(7) cells in controls; P = 0.0006) and decreased in SH (0.8 +/- 0.5 (0.2-1.6) fmol/10(7) cells vs. 2.3 +/- 0.9 (1.1-4.4) fmol/10(7) cells in controls; P = 0.0001), whereas no changes were seen in RT (2.3 +/- 0.7 (1.2-3.3) fmol/10(7) cells vs. 2.3 +/- 0.9 (1.1-4.4) fmol/10(7) cells in controls). In three patients with PHP who were subjected to parathyroidectomy, the calcitriol number came down to normal. Changes of calcitriol receptors in primary and secondary hyperparathyroidism could magnify the consequences of disturbances in serum concentration of calcitriol itself and might play an important role in the development of secondary hyperparathyroidism in uremia.

Bone densitometry and biochemical bone remodeling markers in type 1 diabetes mellitus

Bone mineral density (BMD) at the lumbar spine, quantified by dual energy X-ray absorptiometry, and biochemical bone remodeling markers (serum alkaline phosphatase, osteocalcin, tartrate-resistant acid phosphatase and urinary hydroxyproline) have been studied in 94 patients with diabetes mellitus aged 18-62 years. BMD was normal (1.13 +/- 0.02 g/cm2 in patients vs. 1.16 +/- 0.12 g/cm2 in controls), although it was found to be negatively correlated with HbA1, microalbuminuria, age and the duration of the disease. Serum alkaline phosphatase (188 +/- 75 I.U./l vs. 168 +/- 42 I.U./1; P < 0.03), serum tartrate-resistant acid phosphatase (14.3 +/- 4.3 I.U./l vs. 11.7 +/- 3.7 I.U./l; P < 0.0001) and urinary hydroxyproline (0.018 +/- 0.016 mmol/mmol creatinine vs. 0.011 +/- 0.008 mmol/mmol creatinine; P < 0.001) were higher in diabetics than in controls. Serum osteocalcin was lower (2.5 +/- 1.3 ng/ml vs. 3.4 +/- 1.2 ng/ml; P < 0.0001). No relationship was found between bone remodeling markers and BMD. It is concluded that lumbar BMD is normal in type 1 diabetic patients, although the degree of metabolic control, age and duration of the disease may affect it. In the light of the biochemical markers, bone remodeling may be disturbed in diabetes, but such disturbance seems to be unimportant regarding BMD.

Age-related differences in cytokine secretion

The aim of the present study was to compare cytokine secretion in healthy young and old subjects. Peripheral blood mononuclear cells were isolated from 55 healthy volunteers (aged 23-77 years) and cultured for 24 h in the presence or the absence of lipopolysaccharide (LPS) and 1,25-dihydroxyvitamin D3. Interleukin-1 beta (IL-1), tumor necrosis factor a (TNF) and prostaglandin E2 were measured in the culture supernatants with specific immunoassays. The unstimulated and LPS-stimulated production of IL-1 was significantly higher in the group of subjects older than 55 years than in the group aged less than 55 years. Likewise, there were positive correlations between age and the unstimulated and LPS-stimulated IL-1 secretion (r = 0.50 and 0.63, respectively, p < 0.01 in both cases). However, there were no age-related differences in the secretion of IL-1 in the presence of 1,25-dihydroxyvitamin D or in the secretion of TNF or prostaglandin E2 in any culture condition. These results suggest the existence of subtle abnormalities in cytokine secretion in healthy aged subjects, in comparison with younger individuals. In theory, the increased secretion of IL-1 might play a role in the pathophysiology of some diseases which are frequent in old people, such as osteoporosis.

1,25-Dihydroxyvitamin D3 receptors in peripheral blood mononuclear cells from patients with postmenopausal osteoporosis

A decrease in intestinal calcium absorption, in spite of normal serum calcitriol levels, has been reported in postmenopausal osteoporotic women, raising the possibility of an intestinal resistance to the hormone. The mechanism responsible for it could lie at the receptor or postreceptor level. Intestinal receptors are difficult to study on clinical settings, but calcitriol receptors have been found in peripheral blood mononuclear cells (PBMC). We have studied the PBMC calcitriol receptors by means of Scatchard analysis in 11 postmenopausal osteoporotic women without any treatment and in 12 normal postmenopausal women of similar age. No differences were found in the dissociation constant (Kd) or the concentration of binding sites (Nmax) (Kd in patients: 0.90 +/- 0.75 x 10(-10) M; Kd in controls: 0.85 +/- 0.40 x 10(-10) M; Nmax in patients: 2.4 +/- 1.2 fmol/10(7) cells; Nmax in controls: 2.1 +/- 0.6 fmol/10(7) cells), supporting the contention that the disorder responsible for the resistance to calcitriol in postmenopausal osteoporotic women is located at the postreceptor level. In addition, our study included five postmenopausal osteoporotic women treated with calcitriol (0.5 microgram/day). The number of calcitriol receptors was increased in this group (Nmax: 3.9 +/- 2.0 fmol/10(7) cells vs. 2.1 +/- 0.6 fmol/10(7) cells; P = 0.02).

Interindividual variation in the partition of lipoprotein(a) into lipoprotein subfractions

In order to evaluate cardiovascular risk, we analyzed the lipid composition of HDL and the presence of lipoprotein(a) [Lp(a)] by both agarose gel electrophoresis and enzyme-linked immunoassay (ELISA). In 681 plasmas we found a close correspondence between the existence of a visible sinking pre-beta lipoprotein band and a concentration of Lp(a) higher than 300 mg/L. In the sinking pre-beta(+) samples, the HDL-cholesterol level obtained by differential ultracentrifugation was significantly higher than that obtained by precipitation with the MgCl2-phosphotungstic acid reagent; and the difference between these HDL-cholesterol values was linearly correlated with plasma Lp(a) concentration. Moreover, the other HDL lipid components and the lipid mass ratios of HDL isolated by ultracentrifugation were significantly different from those of HDL isolated by precipitation, and these changes were also correlated with plasma Lp(a). These differences are attributed to Lp(a) because it was detected in the 1.063-1.21 kg/L plasma fractions, whereas it was absent in the plasma supernates after precipitation with MgCl2-phosphotungstic acid. Although to a lesser extent, Lp(a) was also present in the LDL and VLDL density ranges and it directly depended on both the Lp(a) and the triglyceride plasma concentrations. The proportion of Lp(a) in HDL as related to that in LDL density fractions decreased as Lp(a) plasma levels increased, reflecting an interindividual variation of Lp(a) density species. Since 90% of our study population had detectable Lp(a) in plasma, the results reinforce the concept that the ultracentrifugation method is not equivalent to precipitation in most samples, and the contaminant effect of Lp(a) cannot be predicted because of Lp(a) partition into the different lipoprotein fractions.

Stress decreases the serum level of osteocalcin

During a study undertaken to characterize the time course of the osteocalcin response to bone fractures, lower than normal values of serum osteocalcin (1.7 +/- 0.9 vs. 3.3 +/- 1.3 ng/ml, P < 0.001) were found in the basal samples (blood obtained 48-72 h after fracturing). Suspecting that such a decrease could be due to the stress response induced by the fracture, for corticosteroids are known to diminish serum osteocalcin, we extended our study to another two stressful situations of high stress: acute myocardial infarction and elective abdominal surgery. Indeed, the concentration of osteocalcin was also significantly diminished in both of these (2.0 +/- 0.9 ng/ml, P < 0.0005; 1.5 +/- 1.0 ng/ml, P < 0.0001). To further characterize this phenomenon, the time course of osteocalcin changes during the 24 h following abdominal surgery was studied in a second group of patients. The decrease was found to begin soon after surgery. In order to exclude the immobilization present in those three situations as the cause of the decrease in serum osteocalcin, a group of patients with retinal detachment was studied. Their serum osteocalcin levels were normal. It is concluded that serum osteocalcin levels decrease in stressful situations. Therefore, they should be interpreted cautiously when used as a marker of osteoblastic activity in this setting.

[Changes in bone mass in hepatic cirrhosis, chronic obstructive pulmonary disease, insulin-dependent diabetes, and primary hyperparathyroidism]

BACKGROUND

Liver cirrhosis, chronic obstructive pulmonary disease (COPD), insulin-dependent diabetes mellitus and primary hyperparathyroidism are frequent diseases which are considered as risk factors for the development of osteoporosis. However, review of the literature has shown that the studies published on the aforementioned are far from conclusive.

METHODS

By double energy X-ray absorptiometry the bone mineral density (BMD) of the lumbar spine and neck of the femur were determined in 29 patients with liver cirrhosis, 92 with chronic obstructive pulmonary disease (59 treated with corticoids), 81 with insulin-dependent diabetes mellitus and 30 primary hyperparathyroidism (7 operated).

RESULTS

Cirrhotic patients had a normal BMD in both localizations. In patients with COPD, without corticoids, a decrease of 6% was found in the spine and or 13.5% in the neck of the femur while in patients with COPD with corticoids the decrease was of 12% and 7% respectively. Diabetic patients had normal BMD in the spine and a decrease of 6% in the neck of the femur and in patients with hyperparathyroidism a decrease of 6% and normality were found, respectively.

CONCLUSIONS

The repercussion of cirrhosis, insulin-dependent diabetes, and primary hyperparathyroidism on bone mineral density is nul or slight. In patients with chronic obstructive pulmonary disease treated with corticoids decrease in density of the spine is approximately that of a standard deviation. In patients with the latter not treated with corticoids a similar decrease is found in the neck of the femur.

Effects of interleukin-4 on human osteoblast-like cells

Interleukin-4 (IL-4) modulates the activity of a variety of lymphoid, hemopoietic and mesenchymal cells, but little is known about its influence on bone cells. We have studied the effects of IL-4 on the human osteoblast-like cell line MG63. IL-4 (0.1-50 ng/ml) inhibited cell proliferation. The effect did not depend on cell density, but it was more marked in serum-free cultures than in the presence of serum. IL-4 also induced a dose-dependent increase in the expression of alkaline phosphatase stimulated by 1,25-dihydroxyvitamin D3, a marker of differentiated osteoblast activity. However, IL-4 did not modify the secretion of interleukin-6 or tumor necrosis factor. These results suggest that interleukin-4 may play a role as a modulator of osteoblast activity.

[Incidence of hip fractures in Cantabria]

BACKGROUND

Fracture of the hip constitutes a serious social/health care problem with very little information concerning incidence in Spain being available.

METHODS

The diagnosis of hospital admissions and the diagnosis of release from the traumatology units of health care centers for acute patients in Cantabria were reviewed. The study was carried out from the 1st of January to the 31st of December 1988 and only included patients over 49 years of age. Patients who did not habitually reside in the region were excluded. The following data were collected in each case: age, sex, place of residence (urban or rural), time of the year, side fractured, type of injury, previous contralateral fracture and perioperative mortality.

RESULTS

The rate of fracture referred to the population of more than 49 years of age was 277/100,000 in the case of females and 100/100,000 for males. The mean age of women was 80.4 +/- 8.5 years and of men was 76.9 +/- 10.9 years (p > 0.02), respectively. No differences were observed with regard to the place of residence or the time of year. The fracture was left sided in 61% of the females and 58% of the males. The injury was almost always due to a fall. Six percent of the patients had a previous contralateral fracture. Perioperative mortality was 6%.

CONCLUSIONS

The incidence of hip fracture in Cantabria is similar to that of other regions in Spain and lower to that of parts of central and northern Europe and the United States.

Dextran sulfate complexes with potassium phosphate to interfere in determinations of high-density lipoprotein cholesterol

The interference of dextran sulfate with the colorimetric determination of free cholesterol causes an increase in the absorbance that is proportional to the dextran sulfate concentration in the sample. This makes estimation of the free cholesterol concentration unreliable in high-density lipoprotein-containing supernates obtained after plasma precipitation with dextran sulfate/MgCl2. Analysis of the absorption spectrum demonstrated that the absorbance increase was due to turbidity. We observed this effect with colorimetric reagents based on potassium phosphate buffer but not with those based on sodium phosphate or Tris buffers. This effect is ascribed to dextran sulfate because neither the omission of Mg2+ ions nor their chelation with EDTA prevented turbidity, whereas precipitation of dextran sulfate with Ba2+ counteracted this effect. Therefore, potassium phosphate-buffered reagents appear unsuitable for colorimetric lipid determinations in samples containing dextran sulfate.

Dextran Sulfate Complexes with Potassium Phosphate to Interfere in Determinations of High-Density Lipoprotein Cholesterol

The interference of dextran sulfate with the colorimetric determination of free cholesterol causes an increase in the absorbance that is proportional to the dextran sulfate concentration in the sample. This makes estimation of the free cholesterol concentration unreliable in high-density lipoprotein-containing supernates obtained after plasma precipitation with dextran sulfate/MgCl2. Analysis of the absorption spectrum demonstrated that the absorbance increase was due to turbidity. We observed this effect with colorimetric reagents based on potassium phosphate buffer but not with those based on sodium phosphate or Tris buffers. This effect is ascribed to dextran sulfate because neither the omission of Mg2+ ions nor their chelation with EDTA prevented turbidity, whereas precipitation of dextran sulfate with Ba2+ counteracted this effect. Therefore, potassium phosphate-buffered reagents appear unsuitable for colorimetric lipid determinations in samples containing dextran sulfate.