Micro-inclusions in cloudy diamonds from Koffiefontein consist of three main types: silicates, carbonates and brine inclusions. The silicates belong to either the eclogitic or the peridotitic ...paragenesis and both are associated with carbonates and brine. The brine composition is roughly (K,Na)
8(Ca,Fe,Mg)
4SiO(CO
3)
4Cl
10(H
2O)
28–44. Average mass proportions are about 30–42% water, 19–22% chlorine, 14–17% sodium and potassium, 22–25% Fe–Ca–Mg–carbonates, and 3–4% silica. The brine composition is distinct from that of fluids trapped in fibrous diamonds mainly by its high chlorine and low silica content. The close association of carbon-bearing brine, silicate minerals and diamonds suggests that such brines are important for diamond growth in both eclogitic and peridotitic environments. The similarity of brine composition in both environments may indicate that diamonds of both suites grew in a single event.
Populations of sulfide inclusions in diamonds from the Orapa kimberlite pipe in the Kaapvaal-Zimbabwe craton, Botswana, preserve mass-independent sulfur isotope fractionations. The data indicate that ...material was transferred from the atmosphere to the mantle in the Archean. The data also imply that sulfur is not well mixed in the diamond source regions, allowing for reconstruction of the Archean sulfur cycle and possibly offering insight into the nature of mantle convection through time.
Background
Doxycycline, a nonspecific metalloproteinase (MMP) inhibitor, has been demonstrated to impact the strength of the polypropylene (PP) mesh-repaired hernia with an increase in the deposition ...of collagen type 1. The impact of doxycycline with porcine acellular dermal matrices (PADM) is unknown; therefore, we evaluated the impact of doxycycline administration upon hernia repair with PP and PADM mesh.
Methods
Sprague–Dawley rats weighing ~400 g underwent laparotomy with creation of a midline ventral hernia. After a 27-day recovery, animals were randomly assigned to four groups of eight and underwent intraperitoneal underlay hernia repair with either PP or PADM. Groups were assigned to daily normal saline (S) or daily doxycycline in normal saline 10 mg/kg (D) via oral gavage for 8 weeks beginning 24 h preoperatively. Animals were euthanized at 8 weeks and underwent tensiometric testing of the abdominal wall and western blot analyses for collagen subtypes and MMPs.
Results
Thirty-two animals underwent successful hernia creation and repair with either PADM or PP. At 8 weeks, 15 of 16 PP-implanted animals survived with only 12 of 16 PADM-implanted animals surviving. There were no differences in the mesh to fascial interface tensiometric strength between groups. Densitometric counts in the PADM-D group demonstrated increased collagen type 1 compared to PP-S (PADM-D 1286.5, PADM-S 906.9, PP-S 700.4,
p
= 0.037) and decreased collagen type 3 compared to PP-S (PADM-D 7446.9, PADM-S 8507.6, PP-S 11,297.1,
p
= 0.01). MMP-9 levels were increased in PADM-D (PP-S vs. PADM-D,
p
= 0.04), while MMP-2 levels were similar between PADM-D and PADM-S, respectively.
Conclusions
Collagen type 1 deposition at the mesh to fascial interface is enhanced following administration of doxycycline in ventral hernia repairs with porcine acellular dermal matrices. Doxycycline administration may have implications for enhancing hernia repair outcomes using biologic mesh.
On a global scale, peridotitic garnet inclusions in diamonds from the subcratonic lithosphere indicate an evolution from strongly sinusoidal REE
N, typical for harzburgitic garnets, to mildly ...sinusoidal or “normal” patterns (positive slope from LREE
N to MREE
N, fairly flat MREE
N–HREE
N), typical for lherzolitic garnets. Using the Cr-number of garnet as a proxy for the bulk rock major element composition it becomes apparent that strong LREE enrichment in garnet is restricted to highly depleted lithologies, whereas flat or positive LREE–MREE slopes are limited to less depleted rocks. For lherzolitic garnet inclusions, there is a positive relation between equilibration temperature, enrichment in MREE, HREE and other HFSE (Ti, Zr, Y), and decreasing depletion in major elements. For harzburgitic garnets, relations are not linear, but it appears that lherzolite style enrichment in MREE–HREE only occurs at temperatures above 1150–1200 °C, whereas strong enrichment in Sr is absent at these high temperatures. These observations suggest a transition from melt metasomatism (typical for the lherzolitic sources) characterized by fairly unfractionated trace and major element compositions to metasomatism by CHO fluids carrying primarily incompatible trace elements. Melt and fluid metasomatism are viewed as a compositional continuum, with residual CHO fluids resulting from primary silicate or carbonate melts in the course of fractional crystallization and equilibration with lithospheric host rocks.
Eclogitic garnet inclusions show “normal” REE
N patterns, with LREE at about 1× and HREE at about 30× chondritic abundance. Clinopyroxenes approximately mirror the garnet patterns, being enriched in LREE and having chondritic HREE abundances. Positive and negative Eu anomalies are observed for both garnet and clinopyroxene inclusions. Such anomalies are strong evidence for crustal precursors for the eclogitic diamond sources. The trace element composition of an “average eclogitic diamond source” based on garnet and clinopyroxene inclusions is consistent with derivation from former oceanic crust that lost about 10% of a partial melt in the garnet stability field and that subsequently experienced only minor reenrichment in the most incompatible trace elements. Based on individual diamonds, this simplistic picture becomes more complex, with evidence for both strong enrichment and depletion in LREE.
Trace element data for sublithospheric inclusions in diamonds are less abundant. REE in majoritic garnets indicate source compositions that range from being similar to lithospheric eclogitic sources to strongly LREE enriched. Lower mantle sources, assessed based on CaSi–perovskite as the principal host for REE, are not primitive in composition but show moderate to strong LREE enrichment. The bulk rock LREE
N–HREE
N slope cannot be determined from CaSi–perovskites alone, as garnet may be present in these shallow lower mantle sources and then would act as an important host for HREE. Positive and negative Eu anomalies are widespread in CaSi–perovskites and negative anomalies have also been observed for a majoritic garnet and a coexisting clinopyroxene inclusion. This suggests that sublithospheric diamond sources may be linked to old oceanic slabs, possibly because only former crustal rocks can provide the redox gradients necessary for diamond precipitation in an otherwise reduced sublithospheric mantle.
Silicates, carbonates and brine were detected in microinclusions in cloudy diamonds from Koffiefontein. The silicates belong to either the eclogitic or the peridotitic paragenesis. They are similar ...in composition to the larger mineral inclusions found in other Koffiefontein diamonds and record similar pressures and temperatures of formation (1000–1200°C, 4–6 GPa). The clouds also carry additional mineral phases that were not detected before in Koffiefontein: phlogopite, high-Si mica, an Al-Mg-rich phase and carbonates. In many cases silicate minerals coexist together with brine in individual microinclusions. Brines associated with either eclogitic or peridotitic minerals have similar composition and both are rich in water, Cl, K and carbonates (
Izraeli et al., 2001). The above findings, together with the high proportion of cloudy diamonds in Koffiefontein, suggest that brine penetration into neighboring peridotitic and eclogitic rocks was pervasive. The high carbon content of the brine (as dissolved carbonates) initiated diamond growth in both rock types, most, on preexisting diamonds that now form inclusion-free cores. The low aggregation state of nitrogen in the cloudy diamonds, relative to other diamonds from Koffiefontein indicates either a somewhat lower temperature of storage in the mantle (which may be the reason for the presence of brine rather than melt) or a young event of cloudy diamond formation.
Background
Ventral hernia is a commonly occurring surgical problem. Our earlier studies have shown that a 30 mg/kg dose of doxycycline can significantly impact the strength of polypropylene (PP) mesh ...in a rat hernia repair model at 6 and 12 weeks. The objective of the present study was to investigate the dose dependence of doxycycline treatment on hernia repair strengths in rats.
Study design
Fifty-six Sprague-Dawley rats underwent hernia repair with either PP mesh (
n
= 28) or sutures only (primary;
n
= 28); both groups were further divided into four doxycycline groups of seven animals each: control (0 mg/kg), low (3 mg/kg), medium (10 mg/kg), and high (30 mg/kg). One day before hernia repair surgery, animals received doxycycline doses by gavage and continued receiving daily until euthanasia. After 8 weeks, rats were euthanized and tissue samples from hernia repaired area were collected and analyzed for tensile strength using a tensiometer (Instron, Canton, MA, USA), while MMPs 2, 3, and 9, and collagen type 1 and 3 were analyzed by western blotting.
Results
In mesh-repaired animals, medium and high doxycycline dose repaired mesh fascia interface (MFI) showed significant increase in tensile strength when compared to control. In the primary repaired animals, there was no significant difference in MFI tensile strength in any dose group. In medium-dose MFI, there was a significant reduction in MMPs 2, 3, and 9. In this animal group, MFI showed significant increase in collagen 1 and significant reduction in collagen type 3 when compared to control.
Conclusion
It is possible to improve the strength of mesh-repaired tissue by administering a significantly lower dose of the drug, which has implications for translation of the findings.
We present STAR measurements of strange hadron ( K S0, Λ , Λ ¯, Ξ -, Ξ ¯+, Ω -, Ω ¯+ , and Φ ) production at midrapidity ( |y|<0.5 ) in Au+Au collisions at sNN = 7.7–39 GeV from the Beam Energy Scan ...Program at the Relativistic Heavy Ion Collider (RHIC). Transverse-momentum spectra, averaged transverse mass, and the overall integrated yields of these strange hadrons are presented versus the centrality and collision energy. Antibaryon-to-baryon ratios ( Λ ¯/ Λ , Ξ ¯+/ Ξ -, Ω ¯+/ Ω - ) are presented as well and used to test a thermal statistical model and to extract the temperature normalized strangeness and baryon chemical potentials at hadronic freeze-out ( μB/Tch and μS/Tch ) in central collisions. Strange baryon-to-pion ratios are compared to various model predictions in central collisions for all energies. The nuclear modification factors ( RCP ) and antibaryon-to-meson ratios as a function of transverse momentum are presented for all collision energies. The K S0 RCP shows no suppression for pT up to 3.5 GeV/c at energies of 7.7 and 11.5 GeV. The Λ ¯/ K S0 ratio also shows baryon-to-meson enhancement at intermediate pT ( ≈2.5 GeV/c ) in central collisions at energies above 19.6 GeV. Lastly, both observations suggest that there is likely a change of the underlying strange quark dynamics at collision energies below 19.6 GeV.
p62 is a multifunctional cytoplasmic protein able to noncovalently bind ubiquitin and several signaling proteins, suggesting a regulatory role connected to the ubiquitin-proteasome pathway. No ...studies to date have linked p62 protein expression with pathological states. Here we demonstrate the overabundance of p62 protein in malignant breast tissue relative to normal breast tissue. The proteasome inhibitor PSI increased p62 mRNA and protein; however, PSI treatment of breast epithelial cells transfected with the p62 promoter did not affect promoter activity. High levels of prostate-derived Ets factor (PDEF) mRNA have been identified in breast cancer compared to normal breast. Only the PSA and maspin promoters have been identified as targets of this transcription factor. Here we show that PDEF stimulates the p62 promoter through at least two sites, and likely acts as a coactivator. PSI treatment abrogates the PDEF-stimulated increase of p62 promoter activity by 50%. Thus, multiple mechanisms for the induction of p62 exist. We conclude that (1) p62 protein is overexpressed in breast cancer; (2) p62 mRNA and protein increase in response to PSI, with no change of basal promoter activity; (3) PDEF upregulates p62 promoter activity through at least two sites; and (4) PSI downregulates PDEF-induced p62 promoter activation through one of these sites.
Suppressed mite reproduction (SMR) is a heritable trait of the honey bee (Apis mellifera) that can control the parasitic mite, Varroa destructor. The purpose of this study was to determine whether ...adult bees with the SMR trait affect mites in brood after cells are capped. Colonies with or without the SMR trait were each given a comb of newly-capped worker brood that was naturally infested with varroa. Each of 7 source colonies provided a comb of brood to at least one SMR (n = 9) and one control colony (n = 8). These combs were removed from their host colonies 8 days later and mite populations evaluated in cells with bee pupae that were >8 days post-capping. Colonies with SMR bees averaged 2.2% of their cells infested with mites; controls averaged 9.0%. Therefore, bees with the SMR trait apparently removed mites from capped cells. Of the mites that remained, the SMR colonies had a much lower rate of reproductive mites, 20% vs. 71%. This suggests that bees with the SMR trait removed reproductive mites more often than they removed non-reproductive mites. When comparing only the number of mites that produced no progeny, the groups were almost identical averaging 1.2 and 1.3 mites per 100 cells of brood. This suggests that the SMR bees did not remove mites from brood cells if the mites did not lay eggs. By targeting the reproductive mites, bees with the SMR trait give the illusion that nearly all of the mites are non-reproductive. Therefore, our selection for a low frequency of reproductive mites may have produced bees that remove reproductive mites from capped brood.
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