Evaluation of UT/LS hygrometer accuracy by intercomparison during the NASA MACPEX mission

Acquiring accurate measurements of water vapor at the low mixing ratios (< 10 ppm) encountered in the upper troposphere and lower stratosphere (UT/LS) has proven to be a significant analytical challenge evidenced by persistent disagreements between high-precision hygrometers. These disagreements have caused uncertainties in the description of the physical processes controlling dehydration of air in the tropical tropopause layer and entry of water into the stratosphere and have hindered validation of satellite water vapor retrievals. A 2011 airborne intercomparison of a large group of in situ hygrometers onboard the NASA WB-57F high-altitude research aircraft and balloons has provided an excellent opportunity to evaluate progress in the scientific community toward improved measurement agreement. In this work we intercompare the measurements from the Midlatitude Airborne Cirrus Properties Experiment (MACPEX) and discuss the quality of agreement. Differences between values reported by the instruments were reduced in comparison to some prior campaigns but were nonnegligible and on the order of 20% (0.8 ppm). Our analysis suggests that unrecognized errors in the quantification of instrumental background for some or all of the hygrometers are a likely cause. Until these errors are understood, differences at this level will continue to somewhat limit our understanding of cirrus microphysical processes and dehydration in the tropical tropopause layer.

Effects of captan on Apis mellifera brood development under field conditions in California almond orchards

Three almond field trials were conducted during 2003 and 2004 at two locations in central (Fresno County) and northern (Yolo County) California to evaluate the potential effects of commercial applications of Captan on honey bees, Apis mellifera L. Captan was applied at 5.0 kg (AI)/ha during bloom. Hives were evaluated for hive health and brood development parameters for approximately 2 mo after application. This study showed that the application of Captan was not harmful to foraging honey bees or their brood. No treatment-related effects were noted on hive weights, dead bee deformity, number of dead bees, survival of individual larvae, weight of individual emerging adults, and other hive health parameters.

Intestinal fluid volumes and transit of dosage forms as assessed by magnetic resonance imaging

AIM

The gastrointestinal transit of sequentially administered capsules was investigated in relation to the availability of fluid along the intestinal lumen by magnetic resonance imaging.

METHODS

Water-sensitive magnetic resonance imaging was performed on 12 healthy subjects during fasting and 1 h after a meal. Specifiable non-disintegrating capsules were administered at 7, 4 and 1 h prior to imaging.

RESULTS

While food intake reduced the mean fluid volumes in the small intestine (105 +/- 72 mL vs. 54 +/- 41 mL, P < 0.01) it had no significant effect on the mean fluid volumes in the colon (13 +/- 12 mL vs. 18 +/- 26 mL). The mean number of separated fluid pockets increased in both organs after meal (small intestine: 4 vs. 6, P < 0.05; large intestine: 4 vs. 6, P < 0.05). The distribution of capsules between the small and large intestine was strongly influenced by food (colon: 3 vs. 17 capsules, P < 0.01).

CONCLUSIONS

The results show that fluid is not homogeneously distributed along the gut, which likely contributes to the individual variability of drug absorption. Furthermore, transport of fluid and solids through the ileocaecal valve is obviously initiated by a meal-induced gastro-ileocaecal reflex.

[A graded composite material for use in the area of the cranial and facial skull]

For the reconstruction of complex skull defects with individual prefabricated CAD/CAM-implants titanium is well established as bone substitution material. The aim of our studies was to optimize a composite material from polyesters and calcium phosphate. Therefore two different operating procedures (hot pressing and gas-flushing) were combined. As a result the graded composition and porosity of the implants allow a spatial guided degradation progress and cell ingrowth. First biocompatibility tests in vitro with primary human osteoblasts showed a much better pH-characteristic and a better biocompatibility of the composites in comparison with the pure polymers. Degradation experiments in vitro confirmed the different expected degradation rates of the composite materials. As a next step in vivo experiments in ovine skulls are in progress.

[Alternative bone replacement substances for preoperative design of individual CAD/CAM skull implants]

BACKGROUND

The preoperative manufacturing of individual skull implants using computer aided design (CAD) and computer aided manufacturing (CAM) is based on the use of titanium, although the use of other materials is also potentially possible.

THE USE OF OTHER MATERIALS

The use of poly-(D,L-lactide) (PDLLA) as an implant material was investigated using an adult, formalin fixed sheep's head with a complex frontolateral defect. A standard individual titanium implant as well as a resection template made of aluminium were milled in order to allow bone resection and reconstruction within one operation. A mould was made of Teflon for the fabrication of the PDLLA implant using carbon dioxide at high pressure. This procedure allowed a critical comparison to be made of both implant materials and showed that the production of a biodegradable PDLLA implant is possible. At present the titanium implant is superior to the PDLLA implant, as PDLLA settled with slightly larger dimensions than the mould, although the structure itself was exact.

DISCUSSION

The goal of the present research is the fabrication of a functionally graded material made of polylactide, polyglycolide, calcium phosphate and osteoinductive proteins using existing technology, which will meet all of the requirements for stability, resorption kinetics, biocompatibility, radiotranslucence and osteogenic potency of an ideal implant material.

Mouse FcgammaRII is a negative regulator of FcgammaRIII in IgG immune complex-triggered inflammation but not in autoantibody-induced hemolysis

Murine low-affinity receptors for IgG, FcgammaRII and FcgammaRIII, differ by their distinct capacities in mediating down-regulation or activation of cellular effector functions, respectively. In this study, antibodies detecting the mouse Ly-17.1 / 2 alloantigen system are demonstrated to be specific for FcgammaRII with no cross-reactivities to other FcgammaR, including FcgammaRIII. Using these FcgammaRII-specific monoclonal antibodies (mAb), the significance of FcgammaRII inhibition of FcgammaRIII was examined in two models of autoantibody [autoimmune hemolytic anemia (AIHA)]- and IgG immune complex-induced (Arthus reaction) inflammation in C57BL / 6 mice in comparison with FcgammaRII(- / -) and FcgammaRIII(- / -) mice. Our results demonstrate that both FcgammaRIII and FcgammaRII contributed to the binding of erythrocytes opsonized with the pathogenic IgG1 autoreactive anti-murine red blood cell antibody 105-2H. However, the functional blocking with anti-FcgammaRII mAb in C57BL / 6 mice and the lack of FcgammaRII expression in FcgammaRII(- / -) mice, which both lowered the threshold level of FcgammaRIII-triggered phagocytosis in vitro, did not results in enhanced disease development of 105-2H mAb-induced AIHA in vivo. This was in sharp contrast to cutaneous Arthus reaction, where FcgammaRIII-mediated activation was inhibited by FcgammaRII. Together these results show that murine AIHA is markedly different from other FcgammaR-dependent inflammatory diseases where FcgammaRIII is normally counterregulated by FcgammaRII.

FcgammaRIII (CD16)-deficient mice show IgG isotype-dependent protection to experimental autoimmune hemolytic anemia

In autoimmune hemolytic anemia (AIHA), there is accumulating evidence for an involvement of FcgammaR expressed by phagocytic effector cells, but demonstration of a causal relationship between individual FcgammaRs and IgG isotypes for disease development is lacking. Although the relevance of IgG isotypes to human AIHA is limited, we could show a clear IgG isotype dependency in murine AIHA using pathogenic IgG1 (105-2H) and IgG2a (34-3C) autoreactive anti-red blood cell antibodies in mice defective for FcgammaRIII, and comparing the clinical outcome to those in wild-type mice. FcgammaRIII-deficient mice were completely resistent to the pathogenic effects of 105-2H monoclonal antibody, as shown by a lack of IgG1-mediated erythrophagocytosis in vitro and in vivo. In addition, the IgG2a response by 34-3C induced a less severe but persistent AIHA in FcgammaRIII knock-out mice, as documented by a decrease in hematocrit. Blocking studies indicated that the residual anemic phenotype induced by 34-3C in the absence of FcgammaRIII reflects an activation of FcgammaRI that is normally coexpressed with FcgammaRIII on macrophages. Together these results show that the pathogenesis of AIHA through IgG1-dependent erythrophagocytosis is exclusively mediated by FcgammaRIII and further suggest that FcgammaRI, in addition to FcgammaRIII, contributes to this autoimmune disease when other IgG isotypes such as IgG2a are involved.

Interaction of triiodothyronine with 1alpha,25-dihydroxyvitamin D3 on interleukin-6-dependent osteoclast-like cell formation in mouse bone marrow cell cultures

In mouse bone marrow cultures, the formation of osteoclast-like, that is, tartrate-resistant acid phosphatase-positive (TRAP+) and calcitonin (CT) receptor-positive multinucleated cells (MNCs), induced by 10(-10) to 10(-8) mol/L 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3], could be augmented by triiodothyronine (T3), which alone had no effect on osteoclast-like cell formation. The permissive effect of T3 increased the response to 1alpha,25(OH)2D3 by approximately one order of magnitude. Linear concentration dependence was observed between 10(-11) and 10(-8) mol/L T3. Importantly, inhibition of prostaglandin synthesis by indomethacin significantly impeded osteoclast-like cell formation by 1alpha,25(OH)2D3 and abrogated the effect of T3 thereon. Basal interleukin-6 (IL-6) production by cultured marrow cells was significantly stimulated by 1alpha,25(OH)2D3. However, even at an exceedingly high concentration of 20 ng/mL, IL-6 was ineffective in inducing osteoclast-like cell formation. Therefore, any hormonally induced rise in IL-6 release from bone marrow cells could not account for the observed changes in TRAP+ MNC numbers. Nevertheless, the stimulatory effect of 1alpha,25(OH)2D3 on osteoclastogenesis was partially dependent on IL-6 because it could be significantly blocked by a neutralizing monoclonal anti-IL-6 antibody, and to the same extent by a monoclonal anti-IL-6 receptor antibody. Unimpaired signaling through the IL-6/IL-6R system is also a prerequisite for the auxiliary effect of T3 on induction of osteoclast-like cells by 1alpha,25(OH)2D3. Our data provide evidence that 1alpha,25(OH)2D3 induces osteoclast-like cell formation, at least in part, in an IL-6-dependent mode of action, which is also subject to modulation by T3. The mechanism of interaction of the two hormones apparently involves joint stimulation of prostaglandin synthesis.

Radiographic analysis of metatarsus primus varus. 45 feet followed 15 months after distal metatarsal osteotomy and lateral soft-tissue release

We analyzed standardized radiographs of 45 feet in 41 patients with symptomatic hallux valgus and an intermetatarsal angle of 17 (15-23) degrees 15 (9-24) months after distal metatarsal osteotomy and lateral soft-tissue releases. A mean reduction in the II-intermetatarsal angle of 12 degrees and hallux valgus angle of 24 degrees was found. On average, the metatarsus primus varus angle improved by 4 degrees, the I-intermetatarsal angle by 3 degrees and the inclination angle of the first cuneiform by 4 degrees. We conclude that this operation corrects the metatarsus primus varus, without substantially altering the alignment of the long axis of the first metatarsal.

17Beta-estradiol antagonizes effects of 1alpha,25-dihydroxyvitamin D3 on interleukin-6 production and osteoclast-like cell formation in mouse bone marrow primary cultures

In mouse bone marrow primary cultures, the formation of osteoclast-like, i.e. tartrate-resistant acid phosphatase (TRAP)- and calcitonin receptor-positive multinucleated cells (MNC), when induced by 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3), can be suppressed by 17beta-estradiol (17beta-E2), whereas 17alpha-E2 is without any effect. 17beta-E2, above 10(-11) M, significantly reduced 1alpha,25(OH)2D3-mediated TRAP+ MNC formation in cultured bone marrow cells from both female and male mice. The estrogen at 10(-8) M suppressed the peak response to the vitamin D sterol by 50%. 17beta-E2 significantly suppressed basal and 1alpha,25(OH)2D3-stimulated cellular production of interleukin (IL)-6. IL-6 alone, although bone marrow cells in hormone-free culture produced appreciable amounts of the cytokine, did not induce any TRAP+ MNC. Therefore, the changes in IL-6 production induced by the hormones could not be the sole determinant for the extent of TRAP+ MNC formation. However, the stimulatory effect of 1alpha,25(OH)2D3 on osteoclastogenesis nevertheless can be significantly reduced by a neutralizing monoclonal anti-IL-6 antibody. In the presence of 10(-8) M 17beta-E2, the anti-IL-6 monoclonal antibody does not achieve any further suppression of 1alpha,25(OH)2D3-related osteoclast-like cell formation. Our data suggest that induction of osteoclastogenesis by 1alpha,25(OH)2D3 is partially dependent on IL-6 signaling and can be modulated by 17beta-E2 through interference with IL-6 receptor activation, in addition to inhibition of IL-6 production by marrow stromal cells.

[Mobile flatfoot as a sequela of dislocation injury of the Lisfranc joint. A retrospective analysis of 13 patients]

In this retrospective study, 13 patients with subtle Lisfranc joint injuries were examined after a mean period of 23 months using clinical assessment, radiography and dynamic pedographic gait analysis. The aims were to identify the factors leading to a mobile flatfoot deformity, evaluate the functional and clinical outcome of these injuries, and draw practical conclusions for initial management and subsequent intervention. All patients showed a mobile flatfoot deformity, increased motion in the subtalar joint, increased load on the hindfoot, decreased load on the forefoot, and a prolonged contact phase during the stance phase. Radiographs revealed progressive osteoarthrosis in the joint and a residual displacement of the medial Lisfranc joint. An unstable medial Lisfranc joint results in the development of a mobile flatfoot. Initial treatment of a subtly displaced Lisfranc joint should consist of exact anatomical reduction and additional maintenance of the longitudinal arch of the foot. After failed initial treatment, early arthrodesis of the midfoot is recommended as a salvage procedure for the foot.

Growth inhibitory effects on human colon adenocarcinoma-derived Caco-2 cells and calcemic potential of 1 alpha,25-dihydroxyvitamin D3 analogs: structure-function relationships

A panel of synthetic analogs of 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3] bearing one or multiple structural modifications at functionally or metabolically sensitive positions of the molecule, i.e., C-1, 16, 23, 26 and 27, were tested for their growth inhibitory and prodifferentiating potency in human colon adenocarcinoma-derived Caco-2 cells. With respect to the peak response elicited at 10(-8) M, 1 alpha,25-dihydroxy-16-ene-vitamin D3, 1 alpha,25-dihydroxy-23-yne-vitamin D3 and 1 alpha,25-dihydroxy-16,23Z-diene-vitamin D3 suppressed [3H]thymidine incorporation in confluent Caco-2 cells less than 1 alpha,25(OH)2D3. 1 alpha,25-dihydroxy-16,23e-diene-vitamin D3 was at least equipotent to the parent compound, whereas 1 alpha,25-dihydroxy-16-ene-23-yne-vitamin D3 and most conspicuously 1 alpha,25-dihydroxy-26,27-hexafluoro-16-ene-23-yne- vitamin D3 reduced growth of Caco-2 cells to significantly (P < .05) lower levels than 1 alpha,25(OH)2D3. The same rank order was obtained for the ability of the vitamin D compounds to induce activity of the differentiation marker enzyme, alkaline phosphatase, in quiescent Caco-2 cells. Whereas the effect of the synthetic analogs on calcium uptake by cultured embryonic chick duodenum in general was less pronounced than that of 1 alpha,25(OH)2D3, the two most potent antimitogenic compounds, 1 alpha,25-dihydroxy-16-ene-23-yne-vitamin D3 and 1 alpha,25-dihydroxy-26,27-hexafluoro-16-ene-23-yne-vitamin D3, elicited calcium mobilization from cultured neonatal mouse calvaria at a 10-fold lower concentration than the parent compound.(ABSTRACT TRUNCATED AT 250 WORDS)