Teriparatide treatment patterns in osteoporosis and subsequent fracture events: a US claims analysis.

UNLABELLED: The objective of this study was to describe the risk of fragility-related fractures in the 2 years following teriparatide initiation. In an administrative claims analysis of over 11,407 patients, approximately one in eight patients had a new or recurrent fragility-related fracture in the 2 years following teriparatide initiation. INTRODUCTION: The objective of this study was to describe the risk of fragility-related fractures in the 2 years following the initiation of teriparatide in a real-world setting. METHODS: This retrospective study used data from the 2002 to 2011 MarketScan® Commercial and Medicare Supplemental Databases to identify patients 50 years and older with a diagnosis of osteoporosis (ICD-9-CM code 733.0x) who were initiating teriparatide. Patients were required to have continuous medical and pharmacy benefit coverage for the 12 months prior to and 24 months following teriparatide initiation (index event). Teriparatide treatment patterns (persistence and adherence) were described, as was the use of antiresorptive therapy. The primary study outcome was the presence of a new or recurring fragility fracture following the initiation of teriparatide. RESULTS: A total of 11,407 patients met the study criteria (mean age = 69.5, standard deviation = 10.6 years; 92.0% female). One in four (25.6%) patients had fragility fracture claims in the year prior to teriparatide initiation, of which 64.0% were on existing antiresorptive therapy. Overall, 13.4% (n = 1527) of patients had a new or recurrent fracture during the 2-year follow-up period. Forty-eight percent of patients on teriparatide treatment were considered persistent; fragility fractures were more common among patients nonpersistent with teriparatide (15.2%) than among those persistent with teriparatide (11.4%). A higher fracture rate (35.7%) was observed in the cohort with previous fragility fracture then those without pre-index fractures (24%). CONCLUSION: More than 13.4% of patients had new or recurrent fragility-related fractures during the 2 years following the initiation of teriparatide; these fractures were more in common in patients with pre-existing fractures and the patients who were nonpersistent with teriparatide.

Glycoprotein B subtyping of cytomegalovirus (CMV) in the vitreous of patients with AIDS and CMV retinitis.

A 550-bp region of the cytomegalovirus (CMV) glycoprotein B (gB) gene was amplified by polymerase chain reaction (PCR) from 141 vitreous specimens of 120 patients with AIDS and CMV retinitis from three different metropolitan centers. The distribution of gB subtypes I, II, III, and IV were 19%, 43%, 12%, and 21%, respectively, based on restriction enzyme digestion patterns of PCR-amplified DNA. Two patients had simultaneous infection with two different gB subtypes. The ratio of gB subtypes was similar among the three geographically distinct patient populations. Two of 14 patients with bilateral vitreous specimens had different viral subtypes in each eye. In addition, different gB subtypes were observed in 1 of 6 patients with serial specimens. The ratio of different gB subtypes in the vitreous of patients with CMV retinitis is similar to that previously reported in the peripheral blood of patients with advanced AIDS.

In vivo measurement of corneal angiogenesis with video data acquisition and computerized image analysis.

BACKGROUND: Measurement of corneal angiogenesis is useful for quantitating the effects of angiogenic stimuli and for evaluating the efficacy of potential inhibitors of neovascularization. Because accurate methods to record the entire pattern of corneal neovascularization over time in individual living animals do not exist, we have developed a noninvasive method to achieve this goal. EXPERIMENTAL DESIGN: The technique couples video data acquisition methods with computerized analysis of the video images. A stereotactic holding and positioning device allows alignment of the cornea such that it is viewed in a known and repeatable way. Contrast between blood vessels and corneal stroma in the images is enhanced by illuminating the cornea with monochromatic light centered on the peak absorption of hemoglobin. For each observation, multiple overlapping images of the peripheral cornea are recorded on videotape and subsequently digitized with a computer image analysis system. Overlapping regions are found by either statistical cross-correlation or common object identification methods. A montage of nonoverlapping adjacent images is made. Background electronic signals are reduced and contrast is enhanced in each montage with the aid of image processing. Finally, vessel area is calculated by pixel counting after establishing the density range for vessel identification. To demonstrate the utility of the method, we measured over the course of 18 days, the total area of neovascularization in rabbit corneas cauterized with silver/potassium nitrate, and treated topically with either normal saline (control) or 1% prednisolone acetate (100 microliters four times daily for 10 days). The corneal angiogenic response was measured at the time of cautery and at selected intervals thereafter. RESULTS: The amount of angiogenesis in each control cornea increased progressively during the entire observation period. In contrast, the prednisolone-treated corneas manifested less neovascularization than controls during the treatment interval. After treatment ended, the amount of corneal angiogenesis increased slightly in this experimental group. This method provided multiple data points from each animal. CONCLUSIONS: To date, accurate measurement of corneal neovascularization has been a time-consuming process yielding few data points for each animal studied. The new method described, accurately measures even small changes in the area of corneal neovascularization, and allows for multiple observations of the same animal. The technique as currently developed, however, is not applicable to corneas that are markedly opaque or associated with intracorneal hemorrhage.

Changes in distribution, morphology, and tumor necrosis factor-alpha secretion of alveolar macrophage subpopulations during the development of bleomycin-induced pulmonary fibrosis.

Previous studies indicate that heterogeneous alveolar macrophages (AM) play a pivotal role in events associated with bleomycin-induced pulmonary fibrosis. A critical role has been suggested for tumor necrosis factor-alpha (TNF-alpha), a product of activated macrophages, in this fibrotic process. The present study examined whether the characteristics and function (TNF-alpha secretion) of rat AM subpopulations were altered during the development of bleomycin-induced fibrosis. After intratracheal bleomycin treatment, AM were separated into 18 density-defined subpopulations. Bleomycin treatment altered the distribution and morphology of AM subpopulations of densities 1.017 to 1.061 g/ml at all time points studied (4, 14, and 28 days). Subpopulations of densities 1.090 to 1.141 g/ml were affected only at 4 days after bleomycin treatment. Tumor necrosis factor-alpha secretion increased with time in 14- and 28-day samples of bleomycin-treated rats, particularly in subpopulations of densities 1.075 to 1.097 g/ml. These data indicate that alterations in the distribution, morphology, and function of AM subpopulations accompany the development of bleomycin-induced pulmonary fibrosis. When coupled with previous studies suggesting that TNF-alpha plays a role in the fibrotic process in this disease model, these data indicate that AM of densities 1.075 to 1.097 g/ml are responsible for the production of TNF-alpha associated with bleomycin-induced pulmonary fibrosis.

The lack of an effect of intraocular steroids on irradiated fibroblasts in experimental proliferative vitreoretinopathy.

Contraction of intraocular membranes is an important event in the development of proliferative vitreoretinopathy (PVR). When sufficient numbers of cells are present in the vitreous cavity, the retina usually detaches as a result of the contractive force generated by these cells. Steroids reduce the occurrence of retinal detachments in rabbit models of PVR by inhibiting the proliferation of injected fibroblasts. In this study, we used non-proliferative, irradiated cells to determine a possible effect of steroids on preretinal membrane contraction in PVR. We found no clinical difference between steroid treated eyes and sham-treated control eyes. Surgical reduction of the contractile tissue and medical therapy to prevent reproliferation are necessary in order to treat PVR effectively.

In vitro videographic comparison of argon and Nd:YAG laser iridotomy.

We used an in vitro technique with high-magnification video recording to evaluate from the posterior side of the iris the immediate sequence of events during argon and Nd:YAG laser peripheral iridotomy. The observed effects differed strikingly. The argon laser caused a gradual mounding up of iris pigment epithelium with each successive energy application before final penetration. This effect was reduced but not eliminated with higher power levels. The Nd:YAG laser caused complete disruption and dispersal of the pigment epithelium with a single pulse of energy. Additionally, a multiple focal point configuration of the Nd:YAG laser was observed to produce a significantly larger iridotomy than a single focal point configuration for comparable energy settings. These observations may in part explain the observed clinical advantage of the Nd:YAG laser over the argon laser for creation of a patent iridotomy.

The effect of oxygen on corneal neovascularization.

Since tissue oxygen levels are believed to play a pivotal role in new vessel growth in several situations, we studied the effect of several oxygen concentrations (0, 10, 21, 50, 75, or 100%) on corneal vascularization induced in the rat by chemical cautery. We achieved this by perfusing known concentrations of oxygen through goggles fitted over both eyes of the rat after corneal cauterization. Neovascularization was measured in flat corneal preparations with India ink-filled vessels 4 days postcautery using computerized image analysis. The angiogenic response of rats whose eyes were continuously exposed to 0-75% oxygen were not significantly different from each other. The mean response in corneas exposed to 100% oxygen was 10-21% lower than all of the other groups, and this difference was statistically significant when compared to oxygen concentrations of 0, 21 and 75%. The reason for the inhibitory effect of 100% oxygen remains to be determined, but it may represent a toxic effect of oxygen free radicals on the vascular endothelium.

Alterations in lung prostaglandin synthesis and release in murine respiratory mycoplasmosis.

Pathogenetic mechanisms in murine respiratory mycoplasmosis are poorly understood; however, non-specific immune responses appear to be important in controlling the growth of Mycoplasma pulmonis in vitro. To date, no study has examined the role of pulmonary prostaglandin production during the development of M. pulmonis infection. The present study was designed to determine if alterations in pulmonary prostaglandin synthesis and release occur in M. pulmonis infection and the possible role for prostaglandins in the modulation/pathogenesis of murine respiratory mycoplasmosis. Ten to 20 days after intranasal inoculation of pathogen-fee F344 rats with M. pulmonis, lung lavage concentrations of prostaglandin E (PGE) and thromboxane A2 (TxA2) were significantly elevated. To confirm a role for prostaglandins in the pathogenesis of murine mycoplasmosis we blocked the cyclo-oxygenase pathway with indomethacin. Indomethacin-treated rats had significantly lower lavage levels of PGE and TxA2 and significantly increased numbers of M. pulmonis in the lung. These data indicate that prostaglandins may be involved in the pathogenesis of murine respiratory mycoplasmosis, possibly through alteration of mycoplasmacidal and/or mycoplasmastatic mechanisms.

Possible mechanisms of bleomycin-induced fibrosis.

Bleomycin-induced fibrosis is probably the composition of several mechanisms working in sequence and simultaneously. The role(s) and interaction of the cellular, biochemical, and molecular elements of bleomycin-induced fibrosis are examined.

Acid hematin pigmentation of the cornea in stillborn fetuses.

During the postmortem histopathologic evaluation of eyes from stillborn fetuses we noted the presence of a prominent undescribed corneal pigment in 18 of 55 stillborn fetuses. The corneal pigment was frequently associated with documented meconium-stained amniotic fluid, and in no instance was a stained cornea coupled with recorded clear amniotic fluid. Pigmented corneas came from stillborn fetuses with a longer duration of intrauterine death than nonstained corneas. The pigment stained black with the Fontana-Masson stain, was birefringent, and treatment of tissue sections with 5% potassium permanganate and 5% oxalic acid as well as with saturated alcoholic picric acid solution removed the pigment indicating that it is acid hematin. The most likely cause of the acid hematin-stained corneas was tissue acidity created in utero with prolonged intrauterine death.

Interstitial macrophage subpopulations: responsiveness to chemotactic stimuli.

Recent data suggest that interstitial macrophages are a heterogeneous group of cells with several subpopulations. This study was undertaken to determine if there is heterogeneity among rat interstitial macrophage subpopulations ability to respond to chemotactic stimuli. Alveolar macrophages were harvested and separated into density-defined fractions by centrifugation through a continuous iso-osmotic gradient of colloidal silica. Unfractionated and density-defined interstitial macrophages were then characterized as to their ability to migrate towards F-Met-Leu Phen and zymosan activated serum. Interstitial macrophages of density 1.053 and 1.083-1.097 gm/ml were found to have the greatest migrational movement towards F-Met-Leu-Phen which was lower than the unfractionated population. Interstitial macrophage subpopulations migrational movement towards zymosan activated serum exhibited a major peak by macrophages of density 1.053 gm/ml and a minor peak by macrophages of density 1.083-1.097 gm/ml which was lower than the unfractionated population. These results demonstrated that interstitial macrophages are heterogeneous in their migrational ability towards the chemotactic stimuli F-Met-Leu-Phen and zymosan activated serum and that there may be a cooperative interaction between the subpopulations which affects macrophages migrational ability.

The effect of diclofenac acid (Voltaren) on bleomycin-induced pulmonary fibrosis in hamsters.

Bleomycin is an anti-neoplastic compound which produces a time- and dose-dependent pulmonary fibrosis. The mechanisms which cause this fibrosis are not known. However, the ability of bleomycin to modulate prostaglandin synthesis, degradation and circulating levels appears to be central to the fibrosis. Previous studies, which have attempt to modulate bleomycin-induced fibrosis by prevention of prostaglandin synthesis have conflicting results. Therefore, the present study was designed to determine the effects of diclofenac acid, a nonsteroidal anti-inflammatory compound, on the development of bleomycin-induced pulmonary fibrosis. Diclofenac acid pretreatment and daily injections prevented lung collagen accumulation after intratracheal bleomycin. In addition diclofenac acid treatment resulted in significantly lower lung collagen level after intratracheal bleomycin at 14 and 21 days when compared with bleomycin alone. These data indicate that diclofenac acid treatment inhibits bleomycin-induced lung fibrosis possible through the prevention of prostaglandins synthesis.

Dietary fish oil inhibits bleomycin-induced pulmonary fibrosis in the rat.

Intratracheal bleomycin induces pulmonary fibrosis in experimental animals, but the mechanisms involved are poorly understood. Since altered levels of fatty acid metabolites are associated with bleomycin-induced lung injury, we examined the effects of a change in dietary fat on bleomycin-induced fibrosis. Previously we have shown that an essential fatty acid-deficient diet can reduce the severity of bleomycin-induced pulmonary fibrosis. The present study examined the effect of replacement of usual dietary fat with menhaden oil, rich in eicosapentaenoic acid, on the development of pulmonary fibrosis. Weanling rats were raised on a standard laboratory diet or a diet consisting of a fat-free powder to which was added 25% (w/w) of menhaden oil. After 8 weeks of feeding, the animals received either 1.5 units of bleomycin or an equivalent volume of saline intratracheally. In animals receiving the laboratory diet, bleomycin treatment produced a 44% increase in total lung protein content when compared to saline-treated controls (p less than 0.001) and a 77% increase in total lung hydroxyproline content (p less than 0.01). In contrast, bleomycin-treated animals receiving the menhaden oil diet had only small increases, which did not reach statistical significance, in protein and hydroxyproline content in the lung. Bronchoalveolar lavage cellularity did not differ among the treatment groups, but the percentage of lavage macrophages was slightly diminished in bleomycin-treated animals receiving the laboratory diet. Cellular differentials of lavage fluid did not differ significantly between bleomycin- and saline-treated animals receiving the menhaden oil diet. Bleomycin-induced histologic changes, quantitated by morphometric analysis, were significantly reduced with the menhaden oil diet. We conclude that a diet rich in eicosapentaenoic acid can significantly ameliorate bleomycin-induced pulmonary fibrosis, possibly via alterations in eicosanoid metabolism.

Prostaglandin synthesis and release by subpopulations of rat interstitial macrophages.

Recent data indicate that interstitial macrophages are not functionally homogeneous, but are heterogeneous with several subpopulations that differ both morphologically and functionally. Furthermore, interstitial macrophages are believed to be precursor to alveolar macrophages, which have recently been shown to be heterogeneous in their ability to synthesize and release prostaglandins. Considering the apparent importance of prostaglandin synthesis and release in inflammatory and immune responses, the current study was undertaken to determine if interstitial macrophage subpopulations differ in their ability to synthesize and release prostaglandin (PG) E, PGI2, and thromboxane (Tx) A2 after stimulation by calcium ionophore A23187, zymosan, or aggregated IgG. Interstitial macrophages were harvested and separated into 18 density-defined fractions. Density-defined interstitial macrophages (DD-IM) showed marked heterogeneity in prostaglandin synthesis and release. Maximal PGE synthesis and release was seen as a single broad peak after calcium ionophore A23187 and zymosan stimulation. In contrast, no peak in PGE synthesis was seen after aggregated IgG stimulation. PGI2 synthesis also was seen as a single broad peak generated by the lower density interstitial macrophage subpopulations after all stimuli. Similarly, TxA2 synthesis and release was maximal from a broad range of various DD-IM after calcium ionophore A23187, zymosan, and aggregated IgG stimulation. Furthermore, the synthesis and release of TxA2 correlated with the presence of zymosan and IgG receptors on DD-IM. The results demonstrate that DD-IM are heterogeneous in ability to synthesize and release prostaglandins, which are dependent on the stimuli.

Inhibition of phagocytosis and interleukin-1 production in pulmonary macrophages from rats with sialodacryoadenitis virus infection.

To test whether or not sialodacryoadenitis virus (SDAV) infection in rats affects pulmonary macrophage function, we intranasally inoculated pathogen-free F344 rats with SDAV and collected alveolar and interstitial macrophages 5 d later. We assessed Fc receptor-mediated attachment and phagocytosis by phase-contrast microscopic examination of monolayers of alveolar and interstitial macrophages incubated with zymosan, nonopsonized sheep erythrocytes, or erythrocytes opsonized with rabbit antisheep-erythrocyte IgG. Alveolar macrophages from virus-infected rats had significantly (P less than or equal to .05) lower indices of attachment and phagocytosis of opsonized erythrocytes than control macrophages, but there was no difference in attachment of zymosan particles. Interstitial macrophages were not affected. Alveolar macrophages from SDAV-infected rats produced significantly less interleukin-1 than those from control rats, as assessed by testing supernatants from lipopolysaccharide-stimulated macrophage cultures for induction of mouse thymocytes to take up tritiated thymidine. Effects of SDAV infection on lung macrophages could increase host susceptibility to other pathogens or complicate studies of respiratory tract immunity.

Alveolar macrophage subpopulations' responsiveness to chemotactic stimuli.

Recent data suggest that alveolar macrophages are a heterogeneous group of cells with several subpopulations. This study was undertaken to determine if there is heterogeneity among rat alveolar macrophage subpopulations ability to respond to chemotactic stimuli. Alveolar macrophages were harvested by bronchoalveolar lavage and fractionated into density-defined fractions by centrifugation through a continuous isoosmotic gradient of colloidal silica. Unfractionated and density-defined alveolar macrophages were then characterized as to their ability to migrate towards F-Met-Leu-Phen and zymosan-activated serum. Alveolar macrophages of density 1.083-1.097 gm/ml were found to have the greatest migrational movement toward F-Met-Leu-Phen, which was higher than the unfractionated population. In contrast, 2 peaks in alveolar macrophage subpopulations migrational movement towards zymosan-activated serum were noted that were lower than the unfractionated population. These results demonstrated that alveolar macrophages are heterogeneous in their migrational ability towards the chemotactic stimuli F-Met-Leu-Phen and zymosan-activated serum and that there may be a cooperative interaction between the subpopulations that affects macrophage migrational ability.

Neutrophil lactoferrin content: variation among mammals.

Lactoferrin (Lf) in blood and/or marrow neutrophils was semiquantified using indirect immunofluorescence technique in nine mammalian species. Neutrophil iron-binding reactivity (NFeBR), which corresponds primarily to Lf, was also visualized and semiquantified using functional cytochemical (FeNTA-AF) technique at the light microscopic level in these nine and in an additional fifteen mammalian species, and in selected species at the ultrastructural level. Neutrophil immunoreactive Lf was positively correlated with total cellular and granule content of NFeBR among these nine species, and with previously reported concentrations of neutrophil Lf quantified by radioimmunoassay. Relative levels of Lf in neutrophil extracts from rat, hamster, and human were confirmed using SDS-polyacrylamide gel electrophoresis and immunoblotting. Relatively high levels of immunoreactive neutrophil Lf and/or NFeBR were observed in carnivores (ten species) and primates (six species). Among rodents (five species), the levels were variable, and the artiodactyls (four species) studied had low levels. These results demonstrate that neutrophil Lf levels vary widely among mammalian species. In addition, FeNTA-AF technique provides a rapid means of evaluating animals for relative quantities of neutrophil Lf.

Quantitation of corneal neovascularization using computerized image analysis.

We have developed a method for quantitating corneal neovascularization, induced in anesthetized rats by silver nitrate/potassium nitrate cauterization, using a LeMont OASYS video input image analyzer. Corneal vessels are visualized by perfusing the upper half of deeply anesthetized animals with a mixture of 10% india ink, 11% gelatin in lactated Ringer's solution. The eyes are then rapidly cooled using a stream of compressed dichlorodifluoromethane (Freon) to solidify the gelatin mixture. Magnified images of flat preparations of the corneas are acquired using a television camera attached to a dissecting microscope. The images are electronically converted to digital form and the digitized data are stored in the image analyzer. The area of the cornea and blood vessels are independently determined by analyzing the digitized data as discrete values of varying shades of gray (gray-scale analysis). The area and gray scale of the injury and its distance from the corneoscleral limbus can also be measured to determine variability of location and intensity of the injury in different animals. This technique allows the area occupied by new blood vessels during studies on corneal neovascularization in rats to be rapidly quantitated.

Modulation of the development of bleomycin-induced fibrosis by deferoxamine.

Bleomycin is an antineoplastic compound which produces a time- and dose-dependent pulmonary fibrosis. The mechanisms which cause this fibrosis are not known. The ability of bleomycin to produce oxygen radicals in the presence of iron and molecular oxygen appears to be related to the fibrosis. Previous studies, which have examined single time points utilizing the ferric ion chelator deferoxamine and iron-deficient diets, suggest that iron plays a central role in bleomycin-induced pulmonary fibrosis. Therefore, the present study was designed to determine the effects of deferoxamine on the development of bleomycin-induced pulmonary fibrosis. Deferoxamine pretreatment and daily injections resulted in a significant reduction in lung collagen content and lung lipid peroxidation 21 days after intratracheal bleomycin compared with bleomycin treatment alone. In addition deferoxamine treatment significantly inhibited lung DNA increases at 4, 7, and 14 days after bleomycin treatment compared with bleomycin treatment alone. These data indicate that deferoxamine treatment reduces the development of bleomycin-induced pulmonary fibrosis in the later phase. The mechanism might be by the prevention of iron-catalyzed, free-radical formation and modulation of some cellular functions.