The effect of nature exposure on the mental health of patients: a systematic review.

BACKGROUND: The effect of nature-based interventions on self-reported mental well-being in patients with physical disease is gaining increasing attention. However, there is a lack of randomized controlled trials investigating this area. Due to the massive costs in health care systems, there is a need for new strategies to address these issues and an urgent need for attention to this field. Nature-based interventions are low cost, easy to implement, and should get attention within the health care field. Therefore, the objective was to find the impact of nature interventions on mental well-being in humans with a physical disease. METHODS: In four major databases (PubMed, Cinahl, PsycINFO, and Cochrane Library), a systematic review of quantitative studies of nature's impact on self-reported mental health in patients with physical disease was performed. A total of 1909 articles were retrieved but only five met the inclusion criteria and were summarized. RESULTS: All five studies were quantitative, with a control group and a nature-based intervention. A source of heterogeneity was identified: the patients in one of the five studies were psychosomatic. In the four studies with somatic patients, significant benefit of nature on self-reported mental health outcomes was found; the only study that failed to show a significant benefit was the one with psychosomatic patients. CONCLUSION: A significant effect of nature on mental well-being of patients with somatic disease was found. The result in patients with psychosomatic disease is inconclusive, and more studies in this category are needed. Further research on the effect of nature on mental health is merited, with special attention to standardizing intervention type and dose as well as outcome measures within each medical discipline.

Loss of bone mineral of the hip and proximal tibia following rupture of the Achilles tendon.

In a prospective uncontrolled study 12 patients suffering from a rupture of the Achilles tendon treated operatively with surgical repair and post-operative immobilization in a short plaster cast for 6 weeks had bilateral measurements of bone mineral content (BMC) of the proximal tibia and bone mineral density (BMD) of the femoral neck and greater trochanter. The measurements were performed by dual energy X-ray absorptiometry (DEXA) and scans were performed post-operatively within 7 days after the operation and with follow up after 6 weeks, 3, 6, and 12 months. In the operated legs, BMC of the proximal tibia showed a progressive decrease reaching a total bone loss of 6.4% (95%-CL: -10.6%; -2.3%) 1 year after the injury. Bone mineral density at the hip of the operated legs also decreased significantly and 1 year after the injury BMD was 2.5% (95%-CL: -5.5%; 0.5%) and 6.8% (95%-CL: -9.8%; -3.7%) below the initial value in, respectively, the femoral neck and greater trochanter. Patients with a previous Achilles tendon rupture must be considered to be some years ahead in their natural osteoporotic process of the bones of the affected legs, and an increased risk of osteoporotic fractures must be considered not to be only theoretical.

Serological investigation of Mycoplasma genitalium in infertile women.

BACKGROUND: The role of Mycoplasma genitalium in the pathogenesis of pelvic inflammatory disease has not been characterized. METHODS: Sera from 308 infertile women were investigated for antibodies to M. genitalium by immunoblotting. Women with tubal factor infertility (TFI) made up 132 of the patients, 67 of the women had an infertile male partner and 109 were infertile for unknown reasons. RESULTS: Of the TFI patients 29 (22.0%) were seropositive to the major adhesin, MgPa, of M. genitalium versus 11 (6.3%) in the group of women with normal tubes. No cross-reactions between MgPa and P1 of the related Mycoplasma pneumoniae were found. Besides, MgPa positive sera were confirmed by immunoblotting using a cloned fragment of the C-terminal part of MgPa specific to M. genitalium. Chlamydia trachomatis is known to be able to cause infertility as a result of salpingitis. Therefore, the sera were tested against C. trachomatis using a commercial ELISA test. Seventy-five (56.8%) of the TFI patients were seropositive to C. trachomatis. Eight (27.6%) TFI patients seropositive to MgPa were negative to C. trachomatis. CONCLUSIONS: This study indicates that M. genitalium may be an independent risk factor in the development of an inflammatory process leading to scarring of the uterine tubes in women and thereby causing infertility.

A unique sequence of the laminin alpha 3 G domain binds to heparin and promotes cell adhesion through syndecan-2 and -4.

Laminin-5, consisting of the alpha 3, beta 3, and gamma 2 chains, is localized in the skin basement membrane and supports the structural stability of the epidermo-dermal linkage and regulates various cellular functions. The alpha chains of laminins have been shown to have various biological activities. In this study, we identified a sequence of the alpha 3 chain C-terminal globular domain (LG1-LG5 modules) required for both heparin binding and cell adhesion using recombinant proteins and synthetic peptides. We found that the LG3 and LG4 modules have activity for heparin binding and that LG4 has activity for cell adhesion. Studies with synthetic peptides delineated the A3G75aR sequence (NSFMALYLSKGR, residues 1412--1423) within LG4 as a major site for both heparin and cell binding. Substitution mutations in LG4 and A3G75aR identified the Lys and Arg of the A3G75aR sequence as critical for these activities. Cell adhesion to LG4 and A3G75aR was inhibited by heparitinase I treatment of cells, suggesting that cell binding to the A3G75aR site was mediated by cell surface heparan sulfate proteoglycans. We showed by affinity chromatography that syndecan-2 from fibroblasts bound to LG4. Solid-phase assays confirmed that syndecan-2 interacted with the A3G75aR peptide sequence. Stably transfected 293T cells with expression vectors for syndecan-2 and -4, but not glypican-1, specifically adhered to LG4 and A3G75aR. These results indicate that the A3G75aR sequence within the laminin alpha 3 LG4 module is responsible for cell adhesion and suggest that syndecan-2 and -4 mediate this activity.

Cell type-specific differences in glycosaminoglycans modulate the biological activity of a heparin-binding peptide (RKRLQVQLSIRT) from the G domain of the laminin alpha1 chain.

AG73 (RKRLQVQLSIRT), a peptide from the G domain of the laminin alpha1 chain, has diverse biological activities with different cell types. The heparan sulfate side chains of syndecan-1 on human salivary gland cells were previously identified as the cell surface ligand for AG73. We used homologous peptides from the other laminin alpha-chains (A2G73-A5G73) to determine whether the bioactivity of the AG73 sequence is conserved. Human salivary gland cells and a mouse melanoma cell line (B16F10) both bind to the peptides, but cell attachment was inhibited by glycosaminoglycans, modified heparin, and sized heparin fragments in a cell type-specific manner. In other assays, AG73, but not the homologous peptides, inhibited branching morphogenesis of salivary glands and B16F10 network formation on Matrigel. We identified residues critical for AG73 bioactivity using peptides with amino acid substitutions and truncations. Fewer residues were critical for inhibiting branching morphogenesis (XKXLXVXXXIRT) than those required to inhibit B16F10 network formation on Matrigel (N-terminal XXRLQVQLSIRT). In addition, surface plasmon resonance analysis identified the C-terminal IRT of the sequence to be important for heparin binding. Structure-based sequence alignment predicts AG73 in a beta-sheet with the N-terminal K (Lys(2)) and the C-terminal R (Arg(10)) on the surface of the G domain. In conclusion, we have determined that differences in cell surface glycosaminoglycans and differences in the amino acids in AG73 recognized by cells modulate the biological activity of the peptide and provide a mechanism to explain its cell-specific activities.

Identification of cell-binding sites on the Laminin alpha 5 N-terminal domain by site-directed mutagenesis.

The newly discovered laminin alpha(5) chain is a multidomain, extracellular matrix protein implicated in various biological functions such as the development of blood vessels and nerves. The N-terminal globular domain of the laminin alpha chains has an important role for biological activities through interactions with cell surface receptors. In this study, we identified residues that are critical for cell binding within the laminin alpha(5) N-terminal globular domain VI (approximately 270 residues) using site-directed mutagenesis and synthetic peptides. A recombinant protein of domain VI and the first four epidermal growth factor-like repeats of domain V, generated in a mammalian expression system, was highly active for HT-1080 cell binding, while a recombinant protein consisting of only the epidermal growth factor-like repeats showed no cell binding. By competition analysis with synthetic peptides for cell binding, we identified two sequences: S2, (123)GQVFHVAYVLIKF(135) and S6, (225)RDFTKATNIRLRFLR(239), within domain VI that inhibited cell binding to domain VI. Alanine substitution mutagenesis indicated that four residues (Tyr(130), Arg(225), Lys(229), and Arg(239)) within these two sequences are crucial for cell binding. Real-time heparin-binding kinetics of the domain VI mutants analyzed by surface plasmon resonance indicated that Arg(239) of S6 was critical for both heparin and cell binding. In addition, cell binding to domain VI was inhibited by heparin/heparan sulfate, which suggests an overlap of cell and heparin-binding sites. Furthermore, inhibition studies using integrin subunit monoclonal antibodies showed that integrin alpha(3)beta(1) was a major receptor for domain VI binding. Our results provide evidence that two sites spaced about 90 residues apart within the laminin alpha(5) chain N-terminal globular domain VI are critical for cell surface receptor binding.

Quantitative ultrasound image analysis of the supraspinatus muscle.

OBJECTIVE: To develop and validate a method, based on quantitative ultrasound image analysis, to objectively analyse and characterize the ultrasound images of m. supraspinatus. DESIGN: Quantitative ultrasonography was performed on the supraspinatus muscle of 14 healthy subjects. METHODS: A computerized analysis using first-order grey-scale statistics to evaluate the muscle tissue composition was developed and validated. RESULTS: Data from one scanning site were not representative for the whole muscle due to muscle inhomogenity. Using first-order grey-scale statistics the scanning direction was of no importance. By using a scanning session consisting of three different scanning sites along the muscle in two directions, longitudinally and transversely, to characterize the tissue composition of the muscle, a high day-to-day reproducibility was obtained. CONCLUSION: The described scanning session is a relatively sensitive and reproducible method for studying the muscle tissue composition. RelevanceQuantitative ultrasonography seems to be a potential clinical and occupational examination method to detect tissue composition of myalgic muscles compared to healthy muscles.

Identification of a major heparin and cell binding site in the LG4 module of the laminin alpha 5 chain.

The G domain of the laminin alpha chains consists of five homologous G modules (LG1-5) and has been implicated in various biological functions. In this study, we identified an active site for cell and heparin binding within the laminin alpha5 G domain using recombinant proteins and synthetic peptides. Recombinant LG4, LG5, and LG4-5 modules were generated using a mammalian expression system. The LG4 and LG4-5 modules were highly active for cell binding, whereas the LG5 module alone showed only weak binding. Heparin inhibited cell binding to the LG4-5 module, whereas no inhibition was observed with EDTA or antibodies against the integrin beta(1) subunit. These results suggest that the LG4-5 module interacts with a cell surface receptor containing heparan sulfate but not with integrins. Solid-phase assays and surface plasmon resonance measurements demonstrated strong binding of the LG4 and LG4-5 modules to heparin with K(D) values in the nanomolar range, whereas a 16-fold lower value was determined for the LG5 module. Treatment with glycosidases demonstrated that N-linked carbohydrates on the LG5 module are complex-type oligosaccharides. The LG4-5 module, devoid of N-linked carbohydrates, exhibited similar binding kinetics toward heparin. Furthermore, cell binding was unaffected by removal of N-linked glycosylation. To localize active sites on the LG4 module, various synthetic peptides were used to compete with binding of the tandem module to heparin and cells. Peptide F4 (AGQWHRVSVRWG) inhibited binding, whereas a scrambled peptide of F4 failed to compete binding. Alanine replacements demonstrated that one arginine residue within F4 was important for cell and heparin binding. Our results suggest a critical role of the LG4 module for heparan sulfate-containing receptor binding within the laminin alpha5 chain.

Dual energy X-ray absorptiometry in small rats with low bone mineral density.

The feasibility of dual energy X-ray absorptiometry (DXA) using the Norland XR-26 Mark II bone densitometer for measurements of bone mineral content (BMC) and bone mineral density (BMD) in small rats was evaluated. Thirty-two young, isogenic, Lewis rats (weights from 119 g to 227 g) were used; normal rats (n = 7) and rats with low BMD obtained from three different vitamin D-depleted models (n = 25). DXA measurements were performed using the special software for small animals. Duplicate scans of excised femurs performed at 2 mm/second (pixel size of 0.5 mm x 0.5 mm) were very precise measurements with a coefficient of variation (CV) below 1.6% in animals with normal BMD; in rats with low BMD, the CV was significantly higher (P = 0.02-0.04), 7.8% and 4.4% for BMC and BMD, respectively. Regression analysis demonstrated that these measurements were related to the ash weight (R2 > 98.6%). The CV for measurements of the lumbar spine at 10 mm/second (pixel size 0.5 mm x 0.5 mm) was 2.6% and 2.2% for BMC and BMD, respectively in rats with normal BMD, and again higher (P = 0.03-0.14) in rats with low BMD, 7.3% and 4.7%, respectively, for BMC and BMD. Even though low CVs were obtained for total body duplicate scans (scan speed of 20 mm/second and a pixel size of 1.5 mm x 1.5 mm), the measurements were problematic for accuracy because of an overestimation of both BMC and the area of bone. Using these scan parameters the measurements of total body bone mineral could not be recommended in small rats with low BMD.

Physiological response to submaximal isometric contractions of the paravertebral muscles.

STUDY DESIGN: Brief (30-second) isometric trunk extensions at 5%, 20%, 40%, 60%, and 80% of maximal voluntary contraction (MVC) and 3 minutes of prolonged trunk extension (20% MVC) in erect position were studied in nine healthy male subjects. OBJECTIVES: To investigate the intercorrelation between intramuscular pressure and tissue oxygenation of the paravertebral muscles during submaximal isometric contractions and further, to evaluate paravertebral electromyogram and intramuscular pressure as indicators of force development. SUMMARY OF BACKGROUND DATA: Local physiologic responses to muscle contraction are incompletely understood. METHODS: Relative oxygenation was monitored with noninvasive near-infrared spectroscopy, intramuscular pressure was measured with a transducer-tipped catheter, and surface electromyogram was monitored at three recording sites. RESULTS: The root mean square amplitudes of the paravertebral electromyogram (L4, left and right; T12, right) and intramuscular pressure measured in the lumbar multifidus muscle at L4 increased with greater force development in a curvilinear manner. A significant decrease in the oxygenation of the lumbar paravertebral muscle in response to muscle contraction was found at an initial contraction level of 20% MVC. This corresponded to a paravertebral intramuscular pressure of 30-40 mm Hg. However, during prolonged trunk extension, no further decrease in tissue oxygenation was found compared with the tissue oxygenation level at the end of the brief contractions, indicating that homeostatic adjustments (mean blood pressure and heart rate) over time were sufficient to maintain paravertebral muscle oxygen levels. CONCLUSION: At a threshold intramuscular pressure of 30-40 mm Hg during muscle contraction, oxygenation in the paravertebral muscles is significantly reduced. The effect of further increase in intramuscular pressure on tissue oxygenation over time may be compensated for by an increase in blood pressure and heart rate. Surface electromyogram amplitudes and intramuscular pressure can be used as indicators of paravertebral muscle force.

The plasma leptin concentration is closely associated with the body fat mass in nondiabetic uremic patients.

Plasma leptin is associated with the body mass index and, more precisely, with the body fat mass. Plasma leptin has been found to be elevated in uremic patients. This study aimed at investigating the plasma leptin concentration and associations between plasma leptin, body fat mass, and glomerular filtration rate in nondiabetic predialysis uremic patients and in nondiabetic patients on chronic hemodialysis. Plasma leptin, body fat mass, and creatinine clearance were measured in 22 predialysis uremic patients, 18 hemodialysis patients, and 24 healthy control subjects. The logarithmically transformed plasma leptin concentration was closely associated with the body fat mass in all groups (r = 0.93, r = 0.83, and r = 0.72, respectively; p < 0.000001, < 0.000002 and p < 0.001, respectively). In predialysis uremic patients the plasma leptin concentration was slightly elevated as compared with controls 10.4 (3.1-59.5) ng/ml versus 5.4 (1.6-47.5) ng/ml (median and range in parentheses; p < 0. 05), whereas the plasma leptin concentration was normal in hemodialysis patients. Plasma leptin was not significantly associated with the creatinine clearance in predialysis patients. In conclusion; the glomerular filtration rate seemed to have a limited influence on the plasma leptin concentration in nondiabetic uremic subjects matched by body fat mass to controls. The plasma leptin concentration was closely associated with the body fat mass, and the leptin level might, therefore, be useful as an indicator of the fat mass in nondiabetic uremic patients.

Identification of metastasis-promoting sequences in the mouse laminin alpha 1 chain.

Laminin-1, a major basement membrane matrix glycoprotein, enhances adhesion, migration, and metastasis of tumor cells. We have screened 208 overlapping synthetic peptides covering the short and long arms of mouse laminin alpha1 chain for their adhesion activity with B16-F10 mouse melanoma cells. Cell adhesion activity was determined using various amounts of peptides coated on plastic dishes and by measuring cell adhesion on peptide-conjugated Sepharose beads. Nineteen peptides showed B16-F10 cell adhesion activity. Three peptides, designated A-13, -24, and -208, showed the strongest attachment activity in the plate assay, whereas 4 peptides, A-13, -51, -99, and -112, demonstrated the strongest cell adhesion when conjugated to beads. The 19 peptides were tested in vivo for their effect on experimental pulmonary metastasis by B16-F10 cells. Four peptides, A-13, -51, -64, and -119, significantly enhanced metastasis, with A-13 showing the strongest dramatic enhancement. The four metastasis-promoting peptides also stimulated migration of B16-F10 cells in the Boyden chamber assay in vitro with A-13 being the most potent stimulator. In addition, the 4 peptides inhibited laminin-induced cell attachment and migration, which indicates that these four sequences are possible functional B16-F10 cell binding sites in laminin-1. All the four sequences are located on the globular domains of the short arm. Other peptides, including strong adhesion-active peptides, A-24, -99, -112, and a scrambled A-13 peptide, did not stimulate either migration or metastasis. Thus, laminin-1 has multiple active sites in the globular domains of the short arm which promote migration and metastasis of B16-F10 cells.

The muscular load on the lower back and shoulders due to lifting at different lifting heights and frequencies.

The aim of the study was to investigate the muscular load on the lower back and shoulders and the circulatory load on employees at a post center during repetitive lifting of mail transport boxes. A mock-up was designed in the laboratory, a total of nine combinations of lifting height and frequency were studied. Surface EMG was recorded bisymmetrically from m. erector spinae (L3-level) and m. trapezius. The circulatory load was evaluated by measuring the heart rate. The results show a trade off between the low back and shoulders. The maximum load on the low back occurred at the low lifting height (363 and 54.4 cm) whereas the maximum load on the shoulders occurred at the high lifting height (144.9 and 163.0 cm).

Body composition by dual-energy X-ray absorptiometry in patients with Crohn's disease.

BACKGROUND: To study body composition at the whole-body level in patients with Crohn's disease and a history of intestinal resection compared with healthy controls, we performed a cross-sectional study using dual-energy X-ray absorptiometry (DXA). METHODS: Thirty-one patients, 13 men and 18 women, were included. They had a history of Crohn's disease for a mean period of 20 years (range, 4-45 years). All patients had undergone intestinal resections. The colon had been resected in 24 patients, and the mean length of the resected small intestine was 97 cm (range, 0-305 cm). At the time of investigation the Crohn's disease had been in remission for at least 24 months. Patients presented with significantly increased faecal volume and faecal fat excretion. A group of 69 women and 19 men were investigated with DXA and used as reference group. The fat-free mass (FFM), fat mass (FM), percentage fat mass (FM%), and total body mineral content (TBMC) were measured by DXA, and the results were expressed as a z-score. RESULTS: The mean z-score of the body mass index (BMI) was significantly reduced to -0.35 (P=0.036). The FFM was significantly reduced with a mean z-score of -1.74 (P=0.0001). The FM was unchanged (z-score, 0.12; P=0.42). However, FM expressed as percentage of body weight was significantly increased, with a z-score of 0.88 (P=0.001). The TBMC was significantly decreased, with a mean z-score of -1.42 (P=0.0001). There was positive direct correlation between the BMI and TBMC z-scores. There was no correlation between malabsorption and body composition variables. CONCLUSION: Patients with clinically quiescent Crohn's disease showed significant changes in body composition, with low BMI, significant loss of FFM, and unchanged FM. However, when expressed as percentage of body weight, FM was significantly increased. The TBMC was significantly reduced.

Long-term effects of intermittent oral alphacalcidol, calcium carbonate and low-calcium dialysis (1.25 mmol L-1) on secondary hyperparathyroidism in patients on continuous ambulatory peritoneal dialysis.

OBJECTIVES: (i) To examine the effect of alphacalcidol [1 alpha(OH)D3] given as an oral dose twice weekly in combination with CaCO3 and low-calcium dialysis (1.25 mmol L-1) on the secondary hyperparathyroidism in continuous ambulatory peritoneal dialysis (CAPD). (ii) To examine the changes in peritoneal mass transfer for calcium, phosphorus, magnesium, lactate, creatinine, urea, glucose, pH and albumin after shift to low-calcium dialysis solution. DESIGN: An open study in patients on CAPD. SETTING: Renal division, Rigshospitalet, Copenhagen. SUBJECTS: Thirty-nine patients were included and completed 12 weeks of treatment. Thirty of the patients completed 52 weeks of treatment. A peritoneal equilibrium test (PET) was performed in seven patients. INTERVENTIONS: Following two sets of blood samples obtained as basal values the calcium concentration was reduced in the dialysis fluid from 1.75 mmol L-1 to 1.25 mmol L-1. Increasing doses of oral 1 alpha(OH)D3 were then administered under careful control of p-ionized calcium (p-Ca2+) and p-inorganic phosphate (p-P1). Blood samples were obtained every 2-4 weeks for 52 weeks. PET was performed using standard dialysis fluid and 1 week later using low-calcium dialysis fluid after a preceding overnight dwell. Two litres of glucose 22.7 mg mL-1 were used. MAIN OUTCOME MEASURES: Intact parathyroid hormone (PTH), p-Ca2+, p-P1, doses of CaCO3, doses of 1 alpha(OH)D3, peritoneal mass transfer for calcium, inorganic phosphate, magnesium, lactate, creatinine, urea, glucose and albumin. RESULTS: Thirty nine patients with initial PTH values 144 +/- 26 pg mL-1 were followed for 12 weeks and 30 patients for 52 weeks. A negative calcium balance was induced after shifting to low-calcium dialysis fluid. After 2 weeks of treatment a significant increase of PTH by approximately 60% and a small but significant decrease of p-Ca2+ was observed. After 12 weeks of treatment with increasing doses of 1 alpha(OH)D3 and CaCO3, PTH was again reduced to levels not significantly different from the initial values. After 52 weeks of treatment no deterioration of the secondary hyperparathyroidism was seen. CONCLUSIONS: A calcium concentration of 1.25 mmol L-1 in the CAPD dialysate made it possible to reduce the amount of aluminium-containing phosphate binder, to increase the doses of CaCO3 and to use pulse oral 1 alpha(OH)D3 without causing severe hyper-calcaemia in the patients. After a short elevation of PTH, the PTH levels remained at normal or near normal levels and the long-term results clearly demonstrated that an aggravation of the secondary hyperparathyroidism could be inhibited.

Inhibition of PTH secretion by interleukin-1 beta in bovine parathyroid glands in vitro is associated with an up-regulation of the calcium-sensing receptor mRNA.

The principal regulator of parathyroid hormone (PTH) secretion is ionized calcium, but other factors are also known to modulate PTH secretion, such as vitamin D, estrogen, and recently inorganic phosphate. Interleukin-1 (IL-1) possesses a wide variety of biological activities and is produced by leukocytes as well as by various other cells including cells from endocrine tissues and might play a role as a paracrine factor in the control of PTH secretion. We investigated the effect in vitro of IL-1 beta on PTH release, PTHmRNA and the mRNA for the extracellular calcium-sensing receptor (CaR) levels in preparations of bovine parathyroid cells. PTH secretion from cultured parathyroid tissue slices was significantly inhibited in a medium containing IL-1 beta at a concentration of 2000 pg/ml (PTH in % of control: 63.5 +/- 5.3), n=10 (p<0.01). The inhibitory effect of IL-1 beta was not found in preparations of dispersed cells. The inhibitory effect of IL-1 beta could be counteracted by the IL-1 receptor antagonist (IL-1ra), indicating that the inhibitory effect was mediated through the specific IL-1 receptor on the parathyroid cells. IL-1 beta (2000 pg/ml) up-regulated CaRmRNA levels to 180% of control, whereas no change in PTHmRNA was found. IL-1ra abolished the upregulating effect of IL-1 beta on the CaRmRNA. This study demonstrates a direct effect in vitro of IL-1 beta on PTH secretion from bovine parathyroid glands, an effect which may be mediated at least in part through the specific IL-1 receptor causing an upregulation of the calcium-sensing receptor mRNA. IL-1 might therefore play a role as a auto- and/or paracrine factor in the regulation of the PTH secretion.

Body composition changes measured by dual-energy X-ray absorptiometry in patients receiving home parenteral nutrition.

BACKGROUND: To monitor changes in body composition in patients receiving home parenteral nutrition (HPN) and to ascertain whether changes were related to the amount of energy supplied by HPN, we studied prospectively patients with gut failure maintained on HPN. METHODS: Patients were subjected to repeated measurement of body composition by dual-energy X-ray absorptiometry (DXA), the second investigation being performed after a mean period of 20 (range, 11-26) months. Thirty-two patients were included, one patient was excluded, and five patients died during the study period. At inclusion, the patients had received HPN for a mean period of 30 (range, 6-216) months. The indication for HPN was inflammatory bowel disease (n = 16), abdominal cancers (n = 5), and scleroderma and others (n = 11). The fat-free mass (FFM), fat mass (FM), and total body mineral content (TBMC) were measured by DXA. RESULTS: Mean body mass index decreased from 21.18 to 20.96 kg/m2 (P = 0.36). The mean FFM showed a small, insignificant increase to 37.68 kg (P = 0.71). Mean TBMC was unchanged at 2.28 kg, and mean FM decreased from 19.25 to 18.17 kg (P = 0.055). During the study period the mean daily energy supply by HPN was reduced from kcal 1195 to kcal 959 (P = 0.004). There was a direct positive correlation between the individual changes in HPN energy supply and body weight and FFM (r = 0.437, r = 0.410, P < 0.05). CONCLUSION: The body composition of HPN patients was stable, with no change in mean FFM, FM, or TBMC. Individual changes in body weight and FFM correlated with change in HPN energy supply.

Loss of bone mineral of the hip assessed by DEXA following tibial shaft fractures.

We measured prospectively early changes (0-6 months) in bone mineral of the hip, the lumbar spine, and the tibia following tibial shaft fractures (n = 12), and in a cross-sectional study we evaluated the maximal amount of bone loss possible at the hip and tibia following long-term (average 3 years) impaired limb function as a consequence of complicated tibial shaft fractures [delayed union or nonunion (n = 7), chronic osteomyelitis (n = 5), decreased limb length (n = 1), or bone defect (n = 1)]. Bone mineral measurements were performed by dual energy X-ray absorptiometry. Following tibial shaft fractures, a significant decrease in bone mineral density (BMD) was seen at the hip reaching 7% [confidence limits (CL): -10.2%; -3.5%] and 14% (CL: -19.6; -7.8%) after 6 months for the femoral neck and greater trochanter, respectively. In the proximal tibia, bone mineral content (BMC) decreased and was 19% (CL: -27.4%; -9.9%) below the initial value after 6 months. BMD of the lumbar spine remained unchanged. In the cross-sectional study, BMC in the tibia of the injured legs was 43% (CL: -53.2%; -31.9%) below the value in the healthy contralateral legs, and BMD in the femoral neck and greater trochanter, respectively, was 22% (CL: -27.4%; -17.6%) and 24% (CL: -36.3%; -12.1%) below the values in the healthy contralateral legs. With respect to the expected age-related decay of bone mineral after peak bone mass, the loss of bone mineral of the hip and tibia associated with tibial shaft fractures may be considered of clinical importance with increased risk of sustaining a fragility fracture of the lower extremity later in life; and the complicated fractures may even represent a present risk of fracture.

Characterisation of bovine structure-specific recognition protein 1 (SSRP1) cDNA.

A partial bovine SSRP1 (structure-specific recognition protein 1) cDNA has been isolated from a osteoblast cDNA library and sequenced. The bovine SSRP1 cDNA of 1870 bp encoding 460 amino acid residues showed 86% and 98% sequence identity with human SSRP1 at the DNA and protein level, respectively. Expression of SSRP1 mRNA was detected in many human tissues, with a particularly high level in kidney.

Microalbuminuria as an early indicator of osteopenia in male insulin-dependent diabetic patients.

Reduced bone mineral density (BMD), termed diabetic osteopenia, has been reported in patients with insulin-dependent (Type 1) diabetes mellitus (IDDM). To examine BMD in long-term IDDM patients with normal kidney function, but with different degrees of urinary albumin excretion rate (UAER), compared to that of patients with elevated plasma creatinine, 36 IDDM male patients (mean duration 27 years) were subdivided according to UAER (<30, 30-300, >300, >300 mg 24 h(-1) and plasma creatinine 0.120-0.350 mmol l(-1)) and 15 controls were recruited. BMD was measured by dual energy X-ray absorptiometry and UAER by enzyme linked immunosorbent assay. BMD was normal in IDDM patients with normal UAER and reduced in the femoral neck, the trochanter major, and the Wards triangle in patients with increased UAER (p < 0.01, p < 0.05, p < 0.02). BMD correlated to creatinine clearance in both cortical and cancellous bone sites (p < 0.001, p < 0.0001), and inversely to the levels of plasma PTH (p < 0.0005). We conclude that BMD is normal in long-term IDDM male patients with normal kidney function and normal UAER and reduced in patients with increased UAER. Diabetic osteopenia seems to be a progressive phenomenon related to diabetic nephropathy and associated with the decrease in creatinine clearance and with the resulting rise in plasma PTH.