Inversion of the temperature dependence of thermal conductivity of hcp iron under high pressure.

Investigating how the thermal transport properties of iron change under extremely high pressure and temperature conditions, such as those found in the Earth's core, is a major experimental challenge. Over the past decade, there has been a great deal of discussion and debate surrounding the thermal conductivity of the iron-based Earth's core and its thermal evolution. One reason for this may be the variability in the experimentally obtained thermal conductivity of iron at high pressures and temperatures. In this study, we present the experimental results of measuring the thermal conductivity of hexagonal-closed-pack (hcp) iron over a wide pressure-temperature range up to 176 GPa and 2900 K using the pulsed light heating thermoreflectance technique in a laser-heated diamond anvil cell. Our findings indicate that the temperature derivative of the thermal conductivity of hcp iron undergoes a change from negative to positive above 74 GPa, potentially making hcp iron highly conductive at conditions similar to those observed in the Earth's core. This observation represents a notable example of a phenomenon where pressure appears to influence the sign of the temperature derivative of the thermal conductivity of an isostructural metal.

Infliximab biosimilar-induced lupus nephritis: A case report.

We present a case of microhematuria, proteinuria and hypocomplementemia which developed in a 55-year-old female who was being treated with an infliximab biosimilar for rheumatoid arthritis. Renal biopsy showed lupus nephritis (ISN/RPS classification class IV + V). Treatment with the infliximab biosimilar was discontinued, and treatment with prednisolone, hydroxychloroquine and abatacept was started, resulting in clinical remission of lupus nephritis and RA. Although tumour necrosis factor-α α inhibitors are known to induce production of autoantibodies, symptoms are usually limited to skin involvement or arthritis, and renal complications are rare. Physicians should be aware of the risk of lupus nephritis and carefully monitor patients for the development of renal involvement during treatment with tumour necrosis factor-α inhibitors.

Measuring the Electrical Resistivity of Liquid Iron to 1.4 Mbar.

We determined the electrical resistivity of liquid Fe to 135 GPa and 6680 K using a four-probe method in a diamond-anvil cell combined with two novel techniques: (i) enclosing a molten Fe in a sapphire capsule, and (ii) millisecond time-resolved simultaneous measurements of the resistance, x-ray diffraction, and temperature of instantaneously melted Fe. Our results show the minimal temperature dependence of the resistivity of liquid Fe and its anomalous resistivity decrease around 50 GPa, likely associated with a gradual magnetic transition, both in agreement with previous ab initio calculations.

Equation of State of Liquid Iron under Extreme Conditions.

The density of liquid iron has been determined up to 116 GPa and 4350 K via static compression experiments following an innovative analysis of diffuse scattering from liquid. The longitudinal sound velocity was also obtained to 45 GPa and 2700 K based on inelastic x-ray scattering measurements. Combining these results with previous shock-wave data, we determine a thermal equation of state for liquid iron. It indicates that Earth's outer core exhibits 7.5%-7.6% density deficit, 3.7%-4.4% velocity excess, and an almost identical adiabatic bulk modulus, with respect to liquid iron.

Effect of sulfur on sound velocity of liquid iron under Martian core conditions.

Sulfur has been considered to be a predominant light element in the Martian core, and thus the sound velocity of Fe-S alloys at relevant high pressure and temperature is of great importance to interpret its seismological data. Here we measured the compressional sound velocity (VP) of liquid Fe, Fe80S20 and Fe57S43 using ultrasonic pulse-echo overlap method combined with a Kawai-type multi-anvil apparatus up to 20 GPa, likely corresponding to the condition at the uppermost core of Mars. The results demonstrate that the VP of liquid iron is least sensitive to its sulfur concentration in the Mars' whole core pressure range. The comparison of seismic wave speeds of Fe-S liquids with future observations will therefore tell whether the Martian core is molten and contains impurity elements other than sulfur.

Clinicopathological characteristics of cancer associated with Crohn's disease.

PURPOSE: We examined the clinicopathological characteristics and prognosis of patients with cancer associated with Crohn's disease (CD). METHODS: The subjects of this study were patients with cancer confirmed in a resected specimen of bowel, who were treated at our institution between September, 1974 and December, 2014. RESULTS: We analyzed 34 patients (26 men, 8 women, median age at cancer diagnosis 43.5 years, duration of illness 18 years) and found that the number of those with CD complicated with cancer began to drastically increase after 2005. The site of onset of cancer was in an anorectal lesion in 24 (70.6 %) patients. In 17 (50 %) patients, the cancer was diagnosed before surgery; in 3 patients (8.8 %), it was based on pathological findings during surgery; and in 14 patients (41.2 %), it was based on postoperative pathological findings. Mucinous carcinoma was the dominant histological type, seen in 15 patients (44.1 %), while the special type of signet-ring cell carcinoma was found in 4 patients. The cumulative overall 5 year survival rate was 46.2 %. CONCLUSION: In this group of Japanese CD patients, an anorectal lesion was the most frequent site of origin of cancer. As cancer was diagnosed preoperatively in only 50 % of these patients, the overall prognosis was poor, with a cumulative 5 year survival rate of just 46.2 %.

Experimental determination of the electrical resistivity of iron at Earth's core conditions.

Earth continuously generates a dipole magnetic field in its convecting liquid outer core by a self-sustained dynamo action. Metallic iron is a dominant component of the outer core, so its electrical and thermal conductivity controls the dynamics and thermal evolution of Earth's core. However, in spite of extensive research, the transport properties of iron under core conditions are still controversial. Since free electrons are a primary carrier of both electric current and heat, the electron scattering mechanism in iron under high pressure and temperature holds the key to understanding the transport properties of planetary cores. Here we measure the electrical resistivity (the reciprocal of electrical conductivity) of iron at the high temperatures (up to 4,500 kelvin) and pressures (megabars) of Earth's core in a laser-heated diamond-anvil cell. The value measured for the resistivity of iron is even lower than the value extrapolated from high-pressure, low-temperature data using the Bloch-Grüneisen law, which considers only the electron-phonon scattering. This shows that the iron resistivity is strongly suppressed by the resistivity saturation effect at high temperatures. The low electrical resistivity of iron indicates the high thermal conductivity of Earth's core, suggesting rapid core cooling and a young inner core less than 0.7 billion years old. Therefore, an abrupt increase in palaeomagnetic field intensity around 1.3 billion years ago may not be related to the birth of the inner core.

Randomized Controlled Trial of Prophylactic Negative-Pressure Wound Therapy at Ostomy Closure for the Prevention of Delayed Wound Healing and Surgical Site Infection in Patients with Ulcerative Colitis.

BACKGROUND/AIMS: Although negative-pressure wound therapy (NPWT) is likely advantageous for wound healing, the efficacy and safety of its prophylactic use remain unclear for digestive surgery. We performed a prospective randomized controlled study to evaluate the efficacy and safety of this procedure during ileostomy closure. METHODS: We conducted a prospective, randomized study between November 2014 and September 2015. Patients with ulcerative colitis scheduled to undergo ileostomy closure with purse-string suture (PSS) were randomly divided into groups with or without NPWT. The primary endpoint was complete wound healing. The secondary endpoints were incidences of wound complications. RESULTS: A total of 31 patients with PSS alone and 28 patients with PSS + NPWT were enrolled. Wound infection was observed in 1 patient in the PSS-alone condition and 3 patients in the PSS + NPWT condition (p = 0.76). The mean duration of complete wound healing was 37.6 ± 11.7 days in the PSS-alone condition and 33.5 ± 10.0 days in the PSS + NPWT condition (p = 0.18). CONCLUSION: Although no adverse effects were observed in this series, the efficacy of PSS + NPWT was not confirmed. Further clarification of the indication of prophylactic NPWT and its efficacy must be obtained, and the efficacy and safety of NPWT in different dirty/infected surgeries should be evaluated.

Long-term outcomes and sex differences after restorative proctocolectomy in pediatric patients with ulcerative colitis.

BACKGROUND: Restorative proctocolectomy (RPC) for ulcerative colitis (UC) could result in a higher patient quality of life, avoiding frequent disease flares; however, pouch failures and pouch-related complications (PRCs) can develop. PURPOSE: No cohort studies have examined pouch failure and the differences between adult and pediatric patients or the sex differences in pediatric UC. Therefore, the pouch failure rates were compared between adults and pediatric patients, and pouch failure and PRCs in pediatric UC were evaluated. METHODS: UC patients who underwent RPC between January 1987 and June 2014 at Hyogo College of Medicine were included. Patient background characteristics, PRCs, and pouch failure were reviewed. RESULTS: A total of 1347 adult UC patients and 90 (51 boys, 39 girls) pediatric UC patients were included in the study. The cumulative rate of pouch failure at 10years after RPC was significantly higher in pediatric UC (9.5%) than in adult UC (2.1%; p<0.01). In pediatric UC, the independent risk factors for pouch failure were pouchitis (hazard ratio (HR) 19.3) and anal fistula (HR 5.5). Although a sex difference was not seen in pouch failure, an independent risk factor for PRCs was being a girl (HR 2.5). CONCLUSIONS: Pouch failure was more common in pediatric than in adult UC. PRCs after RPC were more common in girls in pediatric UC.

Carbon-depleted outer core revealed by sound velocity measurements of liquid iron-carbon alloy.

The relative abundance of light elements in the Earth's core has long been controversial. Recently, the presence of carbon in the core has been emphasized, because the density and sound velocities of the inner core may be consistent with solid Fe7C3. Here we report the longitudinal wave velocity of liquid Fe84C16 up to 70 GPa based on inelastic X-ray scattering measurements. We find the velocity to be substantially slower than that of solid iron and Fe3C and to be faster than that of liquid iron. The thermodynamic equation of state for liquid Fe84C16 is also obtained from the velocity data combined with previous density measurements at 1 bar. The longitudinal velocity of the outer core, about 4% faster than that of liquid iron, is consistent with the presence of 4-5 at.% carbon. However, that amount of carbon is too small to account for the outer core density deficit, suggesting that carbon cannot be a predominant light element in the core.

Does Pre-Operative Multiple Immunosuppressive Therapy Associate with Surgical Site Infection in Surgery for Ulcerative Colitis.

BACKGROUND: Almost all surgeries for ulcerative colitis (UC) are performed under immunosuppressive conditions. Immunomodulators or biologics, with the exception of corticosteroids, do not appear to be risk factors for post-operative infectious complications. However, many patients are on multiagent immunosuppressive therapy at the time of surgery. Therefore, we evaluated the influence of pre-operative multiple immunosuppressives on the occurrence of surgical site infection (SSI) in UC. METHODS: We reviewed surveillance data from 181 patients who underwent restorative proctocolectomy between January 2012 and March 2014. The incidences of SSI and the possible risk factors among patients receiving different immunosuppressive therapies were compared and analyzed. RESULTS: The incidence of incisional (INC) SSI was 13.3% and that of organ/space (O/S) SSI was 7.2%. The number of immunosuppressives did not significantly correlate with each incidence. Total prednisolone administration ≥12,000 mg (OR 2.6) and an American Society of Anesthesiologists score ≥3 (OR 2.8) were shown to be independent risk factors for overall SSI, whereas corticosteroid use in INC SSI (OR 17.4) and severe disease (OR 5.2) and a large amount of blood loss (OR 3.9) in O/S SSI were identified as risk factors. CONCLUSION: Although a correlation between multiple immunosuppressive therapy and SSIs was not found, it is not recommended that all patients be treated with multiple immunosuppressive therapy. Treatment strategy should be applied based on the patient's condition.

Surgery for Severe Ulcerative Colitis during Pregnancy: Report of Two Cases.

Refractory ulcerative colitis (UC) that does not respond to medical therapy often requires surgery even during pregnancy. Although surgical cases of UC during pregnancy were reported previously, the standard surgical strategy for both colitis and pregnancy was unclear. Herein, fetal and maternal safety as well as the strategy for this unusual surgical procedure during pregnancy in patients with UC are considered. A 28-year-old woman was diagnosed with left-sided moderate UC at 12 weeks of pregnancy; toxic megacolon was suspected, and surgery was required. Although the baby's gestational age was 23 weeks and 3 days, a cesarean section was performed before the colectomy. In a next case, a 28-year-old woman had a 2-year history of left-sided UC. Her colitis flared up at 11 weeks of pregnancy. Colectomy was performed because her colitis was unresponsive to conservative therapy, and the pregnancy was continued, with a transvaginal delivery at 36 weeks. In patients with UC, the need for surgery should be determined promptly based on disease severity, whether or not the patient is pregnant. The need for surgery should not be affected by pregnancy. The pregnancy should be continued for as long as possible when there are no fetal and maternal complications. Both cesarean section and colectomy should be performed independently if necessary.

Clinical features and treatment of ulcerative colitis-related severe gastroduodenitis and enteritis with massive bleeding after colectomy.

INTRODUCTION: Ulcerative colitis (UC) has been recognised as a systemic immune disorder that is not as restricted as colitis. UC-related gastrointestinal lesions with bleeding can develop soon after colectomy and can progress rapidly. Therefore, we considered the clinical features and treatment of these UC-related lesions. METHODS: We reviewed the patient data in our UC surgery database to evaluate its prevalence and features. RESULTS: We found 7/1,100 patients with UC-related lesions between January 2000 and April 2013. These lesions developed at a mean of 24 (range 8-480) days after colectomy. Six of the seven patients suffered from gastrointestinal bleeding as an initial symptom that rapidly developed into massive bleeding or perforations. All of the patients were diagnosed with pancolitis; at the time of colectomy, fulminant, severe, moderate, and mild colitis were presented by four, one, one, and one patients, respectively. All patients with enteritis had consecutively developed other infectious complications, including anastomotic leakage, pyoderma gangrenosum, wound infection, and pneumonia. Although patients with bleeding did not respond to treatment with corticosteroids, they responded well to infliximab soon after its administration. Although six of the seven patients showed cytomegalo virus re-activation in blood or pathological examinations, ganciclovir was not effective in its elimination. CONCLUSION: Although UC-related lesions with an unknown aetiology can occur after colectomy, immediate examination and treatment are required if gastrointestinal bleeding is found after surgery. Because gastrointestinal bleeding from UC-related lesions can worsen rapidly and may be related to mortality, early potent immunosuppressive therapy should be considered.

Spin crossover and iron-rich silicate melt in the Earth's deep mantle.

A melt has greater volume than a silicate solid of the same composition. But this difference diminishes at high pressure, and the possibility that a melt sufficiently enriched in the heavy element iron might then become more dense than solids at the pressures in the interior of the Earth (and other terrestrial bodies) has long been a source of considerable speculation. The occurrence of such dense silicate melts in the Earth's lowermost mantle would carry important consequences for its physical and chemical evolution and could provide a unifying model for explaining a variety of observed features in the core-mantle boundary region. Recent theoretical calculations combined with estimates of iron partitioning between (Mg,Fe)SiO(3) perovskite and melt at shallower mantle conditions suggest that melt is more dense than solids at pressures in the Earth's deepest mantle, consistent with analysis of shockwave experiments. Here we extend measurements of iron partitioning over the entire mantle pressure range, and find a precipitous change at pressures greater than ∼76 GPa, resulting in strong iron enrichment in melts. Additional X-ray emission spectroscopy measurements on (Mg(0.95)Fe(0.05))SiO(3) glass indicate a spin collapse around 70 GPa, suggesting that the observed change in iron partitioning could be explained by a spin crossover of iron (from high-spin to low-spin) in silicate melt. These results imply that (Mg,Fe)SiO(3) liquid becomes more dense than coexisting solid at ∼1,800 km depth in the lower mantle. Soon after the Earth's formation, the heat dissipated by accretion and internal differentiation could have produced a dense melt layer up to ∼1,000 km in thickness underneath the solid mantle. We also infer that (Mg,Fe)SiO(3) perovskite is on the liquidus at deep mantle conditions, and predict that fractional crystallization of dense magma would have evolved towards an iron-rich and silicon-poor composition, consistent with seismic inferences of structures in the core-mantle boundary region.

The structure of iron in Earth's inner core.

Earth's solid inner core is mainly composed of iron (Fe). Because the relevant ultrahigh pressure and temperature conditions are difficult to produce experimentally, the preferred crystal structure of Fe at the inner core remains uncertain. Static compression experiments showed that the hexagonal close-packed (hcp) structure of Fe is stable up to 377 gigapascals and 5700 kelvin, corresponding to inner core conditions. The observed weak temperature dependence of the c/a axial ratio suggests that hcp Fe is elastically anisotropic at core temperatures. Preferred orientation of the hcp phase may explain previously observed inner core seismic anisotropy.

The effect of iron spin transition on electrical conductivity of (Mg,Fe)O magnesiowüstite.

We measured the electrical conductivity of Mg0.81Fe0.19O magnesiowüstite, one of the important minerals comprising Earth's lower mantle, at high pressures up to 135 GPa and 300 K in a diamond-anvil cell (DAC). The results demonstrate that the electrical conductivity increases with increasing pressure to about 60 GPa and exhibits anomalous behavior at higher pressures; it conversely decreases to around 80 GPa and again increases very mildly with pressure. These observed changes may be explained by the high-spin to low-spin transition of iron in magnesiowüstite that was previously reported to occur in a similar pressure range. A very small pressure effect on the electrical conductivity above 80 GPa suggests that a dominant conduction mechanism changes by this electronic spin transition. The electrical conductivity below 2000-km depth in the mantle may be much smaller than previously thought, since the spin transition takes place also in (Mg,Fe)SiO3 perovskite.