Indirect neonatal hyperbilirubinemia in hospitalized neonates on the Thai-Myanmar border: a review of neonatal medical records from 2009 to 2014.

BACKGROUND: Indirect neonatal hyperbilirubinemia (INH) is a common neonatal disorder worldwide which can remain benign if prompt management is available. However there is a higher morbidity and mortality risk in settings with limited access to diagnosis and care. The manuscript describes the characteristics of neonates with INH, the burden of severe INH and identifies factors associated with severity in a resource-constrained setting. METHODS: We conducted a retrospective evaluation of anonymized records of neonates hospitalized on the Thai-Myanmar border. INH was defined according to the National Institute for Health and Care Excellence guidelines as 'moderate' if at least one serum bilirubin (SBR) value exceeded the phototherapy threshold and as 'severe' if above the exchange transfusion threshold. RESULTS: Out of 2980 records reviewed, 1580 (53%) had INH within the first 14 days of life. INH was moderate in 87% (1368/1580) and severe in 13% (212/1580). From 2009 to 2011, the proportion of severe INH decreased from 37 to 15% and the mortality dropped from 10% (8/82) to 2% (7/449) coinciding with the implementation of standardized guidelines and light-emitting diode (LED) phototherapy. Severe INH was associated with: prematurity (< 32 weeks, Adjusted Odds Ratio (AOR) 3.3; 95% CI 1.6-6.6 and 32 to 37 weeks, AOR 2.2; 95% CI 1.6-3.1), Glucose-6-phosphate dehydrogenase deficiency (G6PD) (AOR 2.3; 95% CI 1.6-3.3), potential ABO incompatibility (AOR 1.5; 95% CI 1.0-2.2) and late presentation (AOR 1.8; 95% CI 1.3-2.6). The risk of developing severe INH and INH-related mortality significantly increased with each additional risk factor. CONCLUSION: INH is an important cause of neonatal hospitalization on the Thai-Myanmar border. Risk factors for severity were similar to previous reports from Asia. Implementing standardized guidelines and appropriate treatment was successful in reducing mortality and severity. Accessing to basic neonatal care including SBR testing, LED phototherapy and G6PD screening can contribute to improve neonatal outcomes.

Characterisation of the faecal metabolome and microbiome of Thoroughbred racehorses.

REASONS FOR PERFORMING STUDY: The intestinal bacterial community of the horse is a key determinant of intestinal and whole body health. Understanding the bacterial community structure and function is an important foundation for studies of intestinal health and disease. OBJECTIVES: To describe the faecal bacterial community and volatile organic compounds (VOCs) of the faecal metabolome of healthy Thoroughbred racehorses and to characterise responses to dietary supplementation with amylase-rich malt extract. STUDY DESIGN: Intervention study. METHODS: Faecal samples were collected noninvasively before and 6 weeks after supplementation in 8 privately owned Thoroughbred racehorses in active race training. Faecal metabolome was characterised using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS), with spectral analysis performed using AMDIS and compared against the NIST database. Taxonomic description of the faecal microbiota was achieved using error-corrected 454 pyrosequencing data from 16S rRNA gene amplicons. RESULTS: The faecal metabolome of our study population was dominated by organic acids, alcohols and ketones. We identified 81 different VOCs only 28 of which were present in >50% of samples indicating functional diversity. Faecal VOC profiles differed between first and second sampling point, some VOCs being significantly reduced post supplementation, consistent with a marked response to dietary amylase-rich malt extract. Faecal microbiota was characterised as highly diverse; samples demonstrated verifiable diversity in the range 1200-3000 operational taxonomic units (OTUs) per individual. The methods used also describe high levels of infrequent, low abundance OTUs. Faecal microbial community structure was found to be different following dietary supplementation. Differences in several low abundance bacterial taxa were detected and also some evidence of interhorse variation in response. CONCLUSIONS: The volatile faecal metabolome of Thoroughbred racehorses is dominated by organic acids, alcohols and ketones; this study demonstrates that dietary supplementation with amylase-rich malt extract may significantly alter the profile of VOCs. The faecal microbiome is highly diverse, dominated by Firmicutes and Bacteroidetes. Small but significant changes in microbial community structure were detected following dietary supplementation. This study describes the faecal metabolome and microbiome of healthy Thoroughbred racehorses against which future studies of disease and dietary intervention can be benchmarked.

Adsorption properties of nitrogen dioxide on hybrid carbon and boron-nitride nanotubes.

The properties of pristine carbon nanotubes (CNTs) can be modified in a number of different ways: covalent attachments, substitutional doping, induced defects, and non-covalent interactions with ligands. One unconventional approach is to combine CNTs with boron-nitride nanotubes (BNNTs) to form hybrid carbon and boron-nitride nanotube (CBNNT) materials. In this work, we perform a first-principles density functional theory study on the adsorption properties of NO2 on CBNNT heterostructures. It is found that the adsorption of NO2 is significantly increased on both zigzag CBNNT(8,0) and armchair CBNNT(6,6), as compared to either a pristine CNT or BNNT. For example, the chemisorption of NO2 on CNT(8,0) is found to be endothermic, while the chemisorption of NO2 on CBNNT(8,0) is an exothermic process with a very large binding energy of -27.74 kcal mol(-1). Furthermore, the binding of NO2 on both CBNNT(8,0) and CBNNT(6,6) induces an increase in the conductivity of the nanotube. These characteristics indicate that the CBNNT heterostructures may have significant potential as an NO2 sensor or as a catalyst for NO2 decomposition reactions. Our calculations provide critical information for further evaluation, such as molecular-level adsorption simulations and microkinetic studies.

Plasticity in human pitch perception induced by tonotopically mismatched electro-acoustic stimulation.

Under normal conditions, the acoustic pitch percept of a pure tone is determined mainly by the tonotopic place of the stimulation along the cochlea. Unlike acoustic stimulation, electric stimulation of a cochlear implant (CI) allows for the direct manipulation of the place of stimulation in human subjects. CI sound processors analyze the range of frequencies needed for speech perception and allocate portions of this range to the small number of electrodes distributed in the cochlea. Because the allocation is assigned independently of the original resonant frequency of the basilar membrane associated with the location of each electrode, CI users who have access to residual hearing in either or both ears often have tonotopic mismatches between the acoustic and electric stimulation. Here we demonstrate plasticity of place pitch representations of up to three octaves in Hybrid CI users after experience with combined electro-acoustic stimulation. The pitch percept evoked by single CI electrodes, measured relative to acoustic tones presented to the non-implanted ear, changed over time in directions that reduced the electro-acoustic pitch mismatch introduced by the CI programming. This trend was particularly apparent when the allocations of stimulus frequencies to electrodes were changed over time, with pitch changes even reversing direction in some subjects. These findings show that pitch plasticity can occur more rapidly and on a greater scale in the mature auditory system than previously thought possible. Overall, the results suggest that the adult auditory system can impose perceptual order on disordered arrays of inputs.

Effect of a 300 000-IU loading dose of ergocalciferol (Vitamin D2) on circulating 1,25(OH)2-vitamin D and fibroblast growth factor-23 (FGF-23) in vitamin D insufficiency.

CONTEXT: Several trials have reported an increased risk of fractures and falls after intermittent high-dose vitamin D. Treatment with loading doses of vitamin D may increase 1,25(OH)(2) vitamin D catabolism through changes in calcium/phosphate homeostasis and fibroblast growth factor-23 (FGF-23). OBJECTIVE: The aim was to determine the effects of high-dose vitamin D on circulating concentrations of 1,25(OH)(2) vitamin D and FGF-23 in patients with osteoporosis and vitamin D insufficiency. DESIGN, SETTING, PATIENTS, AND INTERVENTION: We carried out a prospective study of 45 subjects with vitamin D deficiency/insufficiency treated with a bolus dose of 300 000 IU of vitamin D(2) im. Blood samples were obtained at baseline and 1, 2, and 3 months after treatment. OUTCOME MEASURES: Changes in 1,25(OH)(2)-vitamin D and FGF-23 were measured. RESULTS: Loading dose of vitamin D(2) increased 1,25(OH)(2)-vitamin D(2) at 3 months, with a mean [SD] of 41 [56] pmol/L at baseline and 162.3 [137.8] pmol/L at 3 months (P < .001). FGF-23 increased significantly at all time points with a peak at 3 months, with percent change from baseline (mean [SEM]) of 50% [48%] at 3 months (P < .01). There was a positive correlation between FGF-23 and serum phosphate (r = 0.36, P = .024) and calcium (r = 0.532, P < .001) and a negative correlation between total 1,25(OH)(2)-vitamin D and FGF-23 (r = -0.32, P = .036) at 3 months. CONCLUSIONS: High-dose vitamin D increases 1,25(OH)(2)-vitamin D and FGF-23 concentration. Further studies are required to determine whether adjusting vitamin D dose and frequency to minimize increases in FGF-23 may prevent the adverse outcomes associated with high-dose intermittent vitamin D supplementation.

Self-injurious behaviour: limbic dysregulation and stress effects in an animal model.

BACKGROUND: Self-injurious behaviour (SIB) is prevalent in neurodevelopmental disorders, but its expression is highly variable within, and between diagnostic categories. This raises questions about the factors that contribute to aetiology and expression of SIB. Expression of SIB is generally described in relation to social reinforcement. However, variables that predispose vulnerability have not been as clearly characterised. This study reports the aetiology and expression of self-injury in an animal model of pemoline-induced SIB. It describes changes in gross neuronal activity in selected brain regions after chronic treatment with pemoline, and it describes the impact that a history of social defeat stress has on the subsequent expression of SIB during pemoline treatment. METHODS: Experiment 1--Male Long-Evans rats were injected on each of five consecutive days with pemoline or vehicle, and the expression of SIB was evaluated using a rating scale. The brains were harvested on the morning of the sixth day, and were assayed for expression of cytochrome oxidase, an index of sustained neuronal metabolic activity. Experiment 2--Male Long-Evans rats were exposed to a regimen of 12 daily sessions of social defeat stress or 12 daily sessions of handling (i.e. controls). Starting on the day after completion of the social defeat or handling regimen, each rat was given five daily injections of pemoline. The durations of self-injurious oral contact and other stereotyped behaviours were monitored, and the areas of tissue injury were quantified. RESULTS: Experiment 1--Neuronal metabolic activity was significantly lower in a variety of limbic and limbic-associated brain structures in the pemoline-treated rats, when compared with activity in the same regions of vehicle-treated controls. In addition, neuronal activity was low in the caudate-putamen, and in subfields of the hypothalamus, but did not differ between groups for a variety of other brain regions, including nucleus accumbens, substantia nigra, ventral tegmentum, thalamus, amygdala, and cortical regions. Experiment 2--All the pemoline-treated rats exhibited SIB, and whereas the social defeat regimen did not alter the total amount of self-injurious oral contact or other stereotyped behaviours, it significantly increased the severity of tissue injury. CONCLUSIONS: A broad sampling of regional metabolic activity indicates that the pemoline regimen produces enduring changes that are localised to specific limbic, hypothalamic and striatal structures. The potential role of limbic function in aetiology of SIB is further supported by the finding that pemoline-induced self-injury is exacerbated by prior exposure to social defeat stress. Overall, the results suggest brain targets that should be investigated further, and increase our understanding of the putative role that stress plays in the pathophysiology of SIB.

Pressurised hot water extraction with on-line particle formation by supercritical fluid technology.

In this work, an on-line process for pressurised hot water extraction (PHWE) of antioxidants from plants as well as drying of the extract in one step by particle formation based on the use of supercritical carbon dioxide (SC-CO(2)) has been developed. This process has been called WEPO®, water extraction and particle formation on-line. With this process, dried extracts from onion with the same composition of quercetin derivatives as non-dried extracts have been obtained as a fine powder with spherical particles from 250 nm to 4 µm in diameter. The major compounds present in the extract were quercetin-3,4'-diglucoside, quercetin-4'-glucoside and quercetin. An auxiliary inert gas (hot N(2)) was used to enhance the drying process. Parameters such as temperature (120 °C), SC-CO(2) and N(2) pressures (80 and 12.5 bar, respectively) and flow rate of SC-CO(2) (10 ml/min), have been settled by trial-and-error in order to achieve a fine and constant spray formation. Water content, size and morphology, antioxidant capacity and quercetin content of the particles were studied to evaluate the efficiency of the WEPO process. Results were compared with the ones from extracts obtained by continuous flow PHWE followed by freeze-drying. Results showed that both processes gave similar results in terms of antioxidant capacity, concentration of quercetin derivatives and water content, while only WEPO was able to produce defined spherical particles smaller than 4 µm.

Rapamycin impairs trabecular bone acquisition from high-dose but not low-dose intermittent parathyroid hormone treatment.

The osteo-anabolic effects of intermittent parathyroid hormone (PTH) treatment require insulin-like growth factor (IGF) signaling through the IGF-I receptor. A major downstream target of the IGF-I receptor (via Akt) is the mammalian target of rapamycin (mTOR), a kinase involved in protein synthesis. We investigated whether the bone-building effects of intermittent PTH require functional mTOR signaling. Mice were treated with daily PTH 1-34 (0, 10, 30, or 90 microg/kg) for 6 weeks in the presence or absence of rapamycin, a selective inhibitor of mTOR. We found that all PTH doses were effective in enhancing bone mass, whether rapamycin was present or not. Rapamycin had little to no effect on the anabolic response at low (10 microg) PTH doses, small effects in a minority of anabolic measures at moderate doses (30 microg), but the anabolic effects of high-dose PTH (90 microg) were consistently and significantly suppressed by rapamycin ( approximately 4-36% reduction). Serum levels of Trap5b, a marker of resorption, were significantly enhanced by rapamycin, but these effects were observed whether PTH was absent or present. Our data suggest that intermittent PTH, particularly at lower doses, is effective in building bone mass in the presence of rapamycin. However, the full anabolic effects of higher doses of PTH are significantly suppressed by rapamycin, suggesting that PTH might normally activate additional pathways (including mTOR) for its enhanced high-dose anabolic effects. Clinical doses of intermittent PTH could be an effective treatment for maintaining or increasing bone mass among patients taking rapamycin analogs for unrelated health issues.

The effect of oral folic acid upon plasma homocysteine, endothelial function and oxidative stress in patients with type 1 diabetes and microalbuminuria.

AIMS: The purpose of this study was to investigate the effect of oral folic acid supplementation upon plasma homocysteine (HCY), endothelial function and oxidative stress on patients with type 1 diabetes and microalbuminuria to test the hypothesis that oral folic acid would lower plasma HCY and thereby improve endothelial function and reduce oxidant stress in this high-risk group of patients. METHODS: We measured plasma HCY, forearm blood flow, total antioxidant status and whole blood glutathione at baseline and after 2 months treatment with oral folic acid or placebo in 16 patients with type 1 diabetes and microalbuminuria. RESULTS: Plasma HCY fell by 25% in the folic acid group but there was no difference in endothelial function or markers of oxidant stress in the treatment group. CONCLUSIONS: Oral folic acid supplementation successfully lowered plasma HCY levels in patients with type 1 diabetes and microalbuminuria, however this was not associated with improvements in endothelial function or markers of oxidant stress.

Daily treatment of aged ovariectomized rats with human parathyroid hormone (1-84) for 12 months reverses bone loss and enhances trabecular and cortical bone strength.

Most studies that have investigated the anabolic effects of parathyroid hormone (1-84) (PTH) or PTH fragments on the skeleton of ovariectomized (OVX) rats have evaluated the short-term effects of high-dose PTH(1-34) in young animals. This study used densitometry, histomorphometry, and biomechanical testing to evaluate the effects of 12-month daily treatment with low-dose PTH (15 or 30 microg/kg) in rats that were 10 months old at baseline, 4 months after OVX. Bone mineral density (BMD) and bone strength were reduced substantially in control OVX rats. The 15 microg/kg dose of PTH restored BMD to levels similar to those in sham animals within 6 months at the lumbar spine, distal and central femur, and whole body and maintained the BMD gain from 6 to 12 months. The 30 microg/kg dose produced greater effects. Both PTH doses normalized the trabecular bone volume-to-total volume ratio (BV/TV) at lumbar vertebra 3 but not at the proximal tibia (where baseline BV/TV was very low), solely by increasing trabecular thickness. PTH dose-dependently increased bone formation by increasing the mineralizing surface, but only the 30 microg/kg dose increased resorption. PTH increased cortical BMD, area, and thickness, primarily by increasing endocortical bone formation, and restored all measures of bone strength to levels similar to those in sham animals at all skeletal sites. PTH increased bone mass safely; there was no osteoid accumulation, mineralization defect, or marrow fibrosis and there were no abnormal cells. Thus, long-term PTH therapy normalized bone strength in the aged OVX rat, a model of postmenopausal osteoporosis, through increased bone turnover and enhanced formation of both trabecular and cortical bone.

Refining the diagnosis of mitochondrial HMG-CoA synthase deficiency.

Mitochondrial HMG-CoA synthase deficiency is an inherited metabolic disorder caused by a defect in the enzyme that regulates the formation of ketone bodies. Patients present with hypoketotic hypoglycaemia, encephalopathy and hepatomegaly, usually precipitated by an intercurrent infection or prolonged fasting. The diagnosis may easily be missed as previously reported results of routine metabolic investigations, urinary organic acids and plasma acylcarnitines may be nonspecific or normal, and a high index of suspicion is required to proceed to further confirmatory tests. We describe a further acute case in which the combination of urinary organic acids, low free carnitine and changes in the plasma acylcarnitine profile on carnitine supplementation were very suggestive of a defect in ketone synthesis. The diagnosis of mitochondrial HMG-CoA synthase deficiency was confirmed on genotyping, revealing two novel mutations: c.614G > A (R188H) and c.971T > C (M307T). A further sibling, in whom the diagnosis had not been made acutely, was also found to be affected. The possible effects of these mutations on enzyme activity are discussed.

Skeletal efficacy with parathyroid hormone in rats was not entirely beneficial with long-term treatment.

We report the consequences of prolonged treatment with recombinant human parathyroid hormone (1-34) (PTH) in male and ovariectomized female rats with mature skeletons. Intact male and osteopenic, ovariectomized, female F-344 rats were evaluated after 1 year of treatment with 0, 8, or 40 microg/kg/day s.c. PTH. Males and females were about 6 months of age at study initiation; females were ovariectomized (Ovx) for 5 weeks before initiation of PTH treatment. PTH did not affect the survival of either intact males or ovariectomized females. Qualitative histopathology showed expected changes associated with aging in kidneys and proximal tibiae, with no treatment-related anomalies after 1 year of PTH administration. PTH slightly increased the femoral length of ovariectomized females but not that of males. No significant differences in femoral length were observed between sham and Ovx controls. Proximal femora of the males and ovariectomized females given the high dose of 40 microg/kg showed 211 and 186% greater trabecular bone area, 118 and 94% greater cortical thickness, 170 and 189% greater trabecular number, and 321 and 404% greater connectivity (node-to-node struts) compared with respective vehicle controls. Increased trabecular and endocortical surface apposition coincided with a 78 and 70% loss of marrow space for males and females treated with PTH, respectively. Biomechanical strength (ultimate load) of the femoral neck increased by 73 and 76%, respectively, in males and ovariectomized females. Cortical bone analyses of the femoral midshaft showed 105 and 72% increases in bone mineral content, 67 and 55% increases in bone mineral density, and 22 and 10% increases in cross-sectional area for males and ovariectomized females, respectively, with altered shape of femora. Biomechanical analyses of the midshaft showed substantial increases in strength and stiffness but a reduction in ultimate strain, which was likely due to the altered geometry of the midshaft for PTH groups. Aging effects on strength of vertebra and femoral midshaft were reversed by PTH treatment. In summary, the 1-year treatment duration, which represents about 50% of lifetime, did not affect survival and was not associated with any treatment-related anomalies in the kidney or skeleton. PTH reversed the aging process in bones but not kidneys and substantially increased bone mass and strength to well beyond normally attained levels. However, compared with short-term studies reported previously, there seemed to be no advantages to extending PTH treatment to 12 months in rat bones.

Spontaneous stereotypy in an animal model of Down syndrome: Ts65Dn mice.

Stereotyped behaviors (e.g., body rocking) occur at high rates in individuals with mental retardation (e.g., Down syndrome). To determine if spontaneous stereotypy occurs in a murine model of Down syndrome, the home cage behavior of Ts65Dn and control mice was monitored during the dark cycle. Motor activity was further assessed in novel automated test chambers, with acoustic startle and rotor rod paradigms providing additional environmental challenges. Spontaneous stereotypy (repetitive jumping and cage top twirling) was observed in the home cage in approximately half of the Ts65Dn mice, compared with approximately 10% of diploid controls. Repetitive jumping was observed exclusively in the Ts65Dn mice. In the open field, although no differences were found between Ts65Dn and control mice, stereotypic Ts65Dn mice exhibited significantly less locomotor activity and rearing relative to control and nonstereotypic Ts65Dn mice. Ts65Dn mice attained significantly lower rotor rod speeds but did not differ from controls in the amplitude of the acoustic startle response. These environmental challenges did not increase stereotypy over home cage rates but induced stereotypy in two additional animals. The Ts65Dn model may aid in identifying genes associated with the development and expression of stereotypy.

Treatment outcomes for adolescent substance abuse at 4- and 7-month assessments.

This randomized clinical trial evaluated individual cognitive-behavioral therapy (CBT), family therapy, combined individual and family therapy, and a group intervention for 114 substance-abusing adolescents. Outcomes were percentage of days marijuana was used and percentage of youths achieving minimal use. Each intervention demonstrated some efficacy, although differences occurred for outcome measured, speed of change, and maintenance of change. From pretreatment to 4 months, significantly fewer days of use were found for the family therapy alone and the combined interventions. Significantly more youths had achieved minimal use levels in the family and combined conditions and in CBT. From pretreatment to 7 months, reductions in percentage of days of use were significant for the combined and group interventions, and changes in minimal use levels were significant for the family, combined, and group interventions.

Effects of high-dose etidronate treatment on microdamage accumulation and biomechanical properties in beagle bone before occurrence of spontaneous fractures.

We recently demonstrated that suppressed bone remodeling allows microdamage to accumulate and causes reductions in some mechanical properties. However, in our previous study, 1 year treatment with high-dose etidronate (EHDP) did not increase microdamage accumulation in most skeletal sites of dogs in spite of complete remodeling suppression and the occurrence of spontaneous fractures of ribs and/or thoracic spinous processes. This study evaluates the effects of EHDP on microdamage accumulation and biomechanical properties before fractures occur. Thirty-six female beagles, 1-2 years old, were treated daily for 7 months with subcutaneous injections of saline vehicle (CNT) or EHDP at 0.5 (E-low) or 5 mg/kg per day (E-high). After killing, bone mineral measurement, histomorphometry, microdamage analysis, and biomechanical testing were performed. EHDP treatment suppressed intracortical and trabecular remodeling by 60%-75% at the lower dose, and by 100% at the higher dose. Osteoid accumulation caused by a mineralization deficit occurred only in the E-high group, and this led to a reduction of mineralized bone mass. Microdamage accumulation increased significantly by two- to fivefold in the rib, lumbar vertebra, ilium, and thoracic spinous process in E-low, and by twofold in the lumbar vertebra and ilium in E-high. However, no significant increase in damage accumulation was observed in ribs or thoracic spinous processes in E-high where fractures occur following 12 months of treatment. Mechanical properties of lumbar vertebrae and thoracic spinous processes were reduced significantly in both E-low and E-high. These findings suggest that suppression of bone remodeling by EHDP allows microdamage accumulation, but that osteoid accumulation reduces production of microdamage.

New antimicrobial flavanones from Physena madagascariensis.

Two new flavanones (1 and 2) with antibacterial activity were isolated from the methanolic extract of the dried leaves of Physena madagascariensis using activity against Staphylococcus aureus to guide the isolation. A third flavonoid, a flavanone dimer linked by a methylene group (3) was also isolated and proved to be inactive. The structures of 1 and 2 were established primarily from NMR studies, while that of 3 required more extensive mass spectrometric analysis. All three flavanones had lavandulyl units in the limonene form. Flavanones 1 and 2 were active against several bacteria at concentrations as low as 4 microM.

Does suppression of bone turnover impair mechanical properties by allowing microdamage accumulation?

One plausible purpose of bone turnover is to repair bone microdamage. We hypothesized that suppression of bone turnover impairs bone quality by allowing accumulation of microdamage. We investigated the effect of high-dose etidronate (EHDP) on bone's mechanical properties and microdamage accumulation. Skeletally mature beagles, 1-2 years old at the beginning of the study, were treated with daily injections of vehicle or EHDP at 0.5 mg/kg per day or 5.0 mg/kg per day for 1 year. X-rays were taken at baseline and monthly from 7 to 12 months. Bones were taken upon sacrifice and biomechanical tests, histomorphometry, and microdamage analyses were performed. Fractures of ribs and/or thoracic spinous processes were found in 10 of 11 dogs treated with the higher dose EHDP. Only one fracture of a thoracic spinous process was found in dogs treated with the lower dose EHDP, and no fractures were found in the vehicle controls. Biomechanical tests showed reduced mechanical strength in ribs and lumbar vertebrae, but not in the femoral diaphysis or thoracic spinous process in the higher dose EHDP group. Histomorphometric measurements showed a significant reduction of cancellous bone turnover in both EHDP-treated groups compared with controls. In dogs treated with the higher dose EHDP, activation frequency was reduced to zero in both cortical and cancellous bone. Osteoid volume increased significantly, especially in trabecular bone, resulting in reduced mineralized bone volume in the higher dose EHDP group. Microcrack numerical density (Cr.Dn) increased significantly only in the lumbar vertebral body in the higher dose EHDP group, but not in the rib or thoracic spinous process where fractures occurred. These findings show that suppression of bone turnover using high doses of EHDP is associated with fractures of the ribs and spinous processes in dogs. This is most likely the result of excessive amounts of unmineralized bone produced by the inhibition of mineralization at these high doses, rather than by the accumulation of microdamage.

LY353381 x HCl: an improved benzothiophene analog with bone efficacy complementary to parathyroid hormone-(1-34).

LY353381 x HCl is a benzothiophene analog that is structurally related to raloxifene with potent selective estrogen receptor modulator activity in the ovariectomized rat model of postmenopausal osteoporosis. The effects of LY353381 x HCl on bones, body weight, and uterine weight were evaluated in 7-month-old rats with osteopenia that was induced by ovariectomizing animals for 1 month before initiation of treatment with several agents individually, in combination, or in sequence. LY353381 x HCl was administered daily by itself for 90 days, in combination with the amino-terminal fragment of PTH-(1-34) (PTH) for 90 days, or sequentially after PTH when PTH was discontinued after 45 days of treatment. Additionally, comparisons were made of animals treated with PTH alone, 17alpha-ethynyl estradiol alone, equine estrogens (Premarin) alone, raloxifene alone, or combinations of PTH and equine estrogens or raloxifene. Ovariectomy induced increases in the rate of bone turnover and body weight while decreasing bone mineral density, bone mineral content, bone strength, trabecular bone volume, trabecular thickness, trabecular number, and uterine weight. LY353381 x HCl at 0.01-1 mg/kg had marginal effects on body weight and no effect on uterine weight compared with those in ovariectomized controls, in contrast to 17alpha-ethynyl estradiol or equine estrogens. LY353381 x HCl prevented further bone loss due to ovariectomy in tibia, femora, and lumbar vertebra, like 17alpha-ethynyl estradiol but unlike equine estrogens. LY353381 x HCl prevented the resorption of trabecular bone spicules, like 17alpha-ethynyl estradiol, but inhibited bone formation activity to a lesser extent than 17alpha-ethynyl estradiol. In this model, 17alpha-ethynyl estradiol appeared to be more efficacious after 3 months of treatment than equine estrogens in the proximal tibia metaphysis, suggesting efficacy differences between metabolites of 17beta-estradiol in bone. PTH at 10 microg/kg had no effect on body weight or uterine weight, but significantly increased bone mass to beyond those in sham-operated controls, baseline controls, and groups receiving other individual treatments at both axial and appendicular sites. The combination of LY353381 x HCl and PTH increased bone mass at a faster rate and to a greater extent than PTH alone or the combinations of equine estrogens/PTH and raloxifene/PTH at trabecular bone sites. The LY353381 x HCl/PTH combination improved bone mass and quality beyond any agent alone in regions enriched for cancellous bone, but was not significantly better than PTH alone on cortical bone. Additionally, when PTH was discontinued at 45 days, LY353381 x HCl prevented the rapid loss of bone observed in controls. Therefore, LY353381 x HCl appears to be useful by itself, in combination, or in sequence with PTH to replace lost bone in postmenopausal women.

7-Oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridines as novel inhibitors of human eosinophil phosphodiesterase.

High-throughput file screening against inhibition of human lung PDE4 led to the discovery of 3-ethyl-1-(4-fluorophenyl)-6-phenyl-7-oxo-4, 5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine (11) as a novel PDE4 inhibitor. Subsequent SAR development, using an eosinophil PDE assay, led to analogues up to 50-fold more potent than 11 with IC50 values of 0.03-1.6 microM. One such compound, CP-220,629 (22) (IC50 = 0.44 microM), was efficacious in the guinea pig aerosolized antigen induced airway obstruction assay (ED50 2.0 mg/kg, po) and demonstrated a significant reduction in eosinophil (55%), neutrophil (65%), and IL-1beta (82%) responses to antigen challenge in atopic monkeys (10 mg/kg, po).

Fluoride treatment increased serum IGF-1, bone turnover, and bone mass, but not bone strength, in rabbits.

We hypothesized that fluoride partly acts by changing the levels of circulating calcium-regulating hormones and skeletal growth factors. The effects of oral fluoride on 24 female, Dutch-Belted, young adult rabbits were studied. The rabbits were divided into two study groups, one control and the other receiving about 16 mg fluoride/rabbit/day in their drinking water. After 6 months of fluoride dosing, all rabbits were euthanized and bone and blood samples were taken for analyses. Fluoride treatment increased serum and bone fluoride levels by over an order of magnitude (P < 0.001), but did not affect body weight or the following serum biochemical variables: urea, creatinine, phosphorus, total protein, albumin, bilirubin, SGOT, or total alkaline phosphatase. No skeletal fluorosis or osteomalacia was observed histologically, nor did fluoride affect serum PTH or Vitamin D metabolites (P > 0.4). BAP was increased 37% (P < 0.05) by fluoride; serum TRAP was increased 42% (P < 0.05); serum IGF-1 was increased 40% (P < 0.05). Fluoride increased the vertebral BV/TV by 35% (P < 0.05) and tibial ash weight by 10% (P < 0.05). However, the increases in bone mass and bone formation were not reflected in improved bone strength. Fluoride decreased bone strength by about 19% in the L5 vertebra (P < 0.01) and 25% in the femoral neck (P < 0. 05). X-ray diffraction showed altered mineral crystal thickness in fluoride-treated bones (P < 0.001), and there was a negative association between crystal width and fracture stress of the femur (P < 0.02). In conclusion, fluoride's effects on bone mass and bone turnover were not mediated by PTH. IGF-1 was increased by fluoride and was associated with increased bone turnover, but was not correlated with bone formation markers. High-dose fluoride treatment did not improve, but decreased, bone strength in rabbits, even in the absence of impaired mineralization.