Accuracy of computerized tomography in determining hepatic tumor size in patients receiving liver transplantation or resection

Computerized tomography (CT) of liver is used in oncologic practice for staging tumors, evaluating response to treatment, and screening patients for hepatic resection. Because of the impact of CT liver scan on major treatment decisions, it is important to assess its accuracy. Patients undergoing liver transplantation or resection provide a unique opportunity to test the accuracy of hepatic-imaging techniques by comparison of finding of preoperative CT scan with those at gross pathologic examination of resected specimens. Forty-one patients who had partial hepatic resection (34 patients) or liver transplantation (eight patients) for malignant (30 patients) or benign (11 patients) tumors were evaluable. Eight (47%) of 17 patients with primary malignant liver tumors, four (31%) of 13 patients with metastatic liver tumors, and two (20%) of 10 patients with benign liver tumors had tumor nodules in resected specimens that were not apparent on preoperative CT studies. These nodules varied in size from 0.1 to 1.6 cm. While 11 of 14 of these nodules were 1.0 cm. These results suggest that conventional CT alone may be insufficient to accurately determine the presence or absence of liver metastases, extent of liver involvement, or response of hepatic metastases to treatment

The effect of different types of hepatic injury on the estrogen and androgen receptor activity of liver

Mammalian liver contains receptors for both estrogens and androgens. Hepatic regeneration after partial hepatectomy in male rats is associated with a loss of certain male-specific hepatic characteristics. In this study we investigated the effects of lesser forms of hepatic injury on the levels of estrogen and androgen receptor activity in the liver. Adult male rats were subjected to portacaval shunt, partial portal vein ligation, hepatic artery ligation, or two-thirds partial hepatectomy. Another group of animals was treated with cyclosporine. At the time of sacrifice the livers were removed and used to determine the estrogen and androgen receptor activity in the hepatic cytosol. A significant reduction (p < 0.05) in the hepatic cytosolic androgen receptor activity and a slight increase in the estrogen receptor activity occurred following total portosystemic shunting. Partial ligation of the portal vein, which produces a lesser degree of portosystemic shunting, had no effect on the levels of the estrogen and androgen receptor activity present within hepatic cytosol. Cyclosporine-treated animals had significantly greater (p < 0.01) levels of estrogen receptor activity in the hepatic cytosol compared to vehicle-treated control animals. Levels of estrogen and androgen receptor activity within the hepatic cytosol remained unchanged after ligation of the hepatic artery. The reduction in the cytosolic estrogen and androgen receptor activity in the liver after partial hepatectomy was confirmed. In summary, certain types of hepatic injury are associated with profound changes in the estrogen and androgen receptor content within the liver. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

The protective effect of FK506 pretreatment against renal ischemia/reperfusion injury in rats

The effect of pretreatment with FK506 on renal ischemia and reperfusion (I/R) injury was investigated using a rat model. Animals were assigned to one of two groups (20 rats each). Group 1 animals (controls) received 0.5 ml saline while group 2 animals received FK506 (0.3 mg/kg), administered intravenously 24 hr prior to the induction of renal ischemia. A 60-min period of ischemia of the right kidney was induced, and upon reperfusion a left nephrectomy was performed. Blood samples for estimation of BUN, creatinine, and tumor necrosis factor were collected on days 0 (preischemia), 1, 2, 3, 5, 7, and 10 (postischemia). Rats were sacrificed after day 10 and renal tissue was examined histologically. All animals survived the ischemic episode. FK506 pretreatment significantly reduced the serum levels of BUN (P<0.02), creatinine (P<0.02), and TNF (P<0.05) as compared with that seen in controls. Histologically, at day 10, the kidneys showed the expected sequelae of prior renal I/R with various degrees of tubular damage. However, no objective differences were evident between the two groups. Based upon these data, it can be concluded that (1) FK506 pretreatment ameliorates the functional renal injury associated with I/R, (2) renal ischemia induces the release of TNF, and (3) FK506 pretreatment results in a significant inhibition of TNF production. These data suggest that the release of TNF may be responsible for the increasing of BUN and creatinine levels seen after renal I/R and that pretreatment of renal donors with FK506 may improve renal function in the immediate post-transplant period. © 1992 by Williams and Wilkins

Allosteric inhibition of carnosinase (CN1) by inducing a conformational shift

In humans, low serum carnosinase (CN1) activity protects patients with type 2 diabetes from diabetic nephropathy. We now characterized the interaction of thiol-containing compounds with CN1 cysteine residue at position 102, which is important for CN1 activity. Reduced glutathione (GSH), N-acetylcysteine and cysteine (3.2 \uc2\ub1 0.4, 2.0 \uc2\ub1 0.3, 1.6 \uc2\ub1 0.2 \uc2\ub5mol/mg/h/mM; p &lt;.05) lowered dose-dependently recombinant CN1 (rCN1) efficiency (5.2 \uc2\ub1 0.2 \uc2\ub5mol/mg/h/mM) and normalized increased CN1 activity renal tissue samples of diabetic mice. Inhibition was allosteric. Substitution of rCN1 cysteine residues at position 102 (Mut1C102S) and 229 (Mut2C229S) revealed that only cysteine-102 is influenced by cysteinylation. Molecular dynamic simulation confirmed a conformational rearrangement of negatively charged residues surrounding the zinc ions causing a partial shift of the carnosine ammonium head and resulting in a less effective pose of the substrate within the catalytic cavity and decreased activity. Cysteine-compounds influence the dynamic behaviour of CN1 and therefore present a promising option for the treatment of diabetes

Coupling charge and topological reconstructions at polar oxide interfaces

In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion-symmetry across the heterointerfaces. A notable example is the interface between polar and non-polar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way to the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wavefunctions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO$_3$, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO$_3$, a polar wide-bandgap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO$_2$/SrO interface configuration, leading to excess charge being pinned near the LaAlO$_3$/SrRuO$_3$ interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction modifies the momentum-space Berry curvature in SrRuO$_3$, driving a reorganization of the topological charges in the band structure. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.Comment: 5 pages main text (4 figures), 29 pages of supplementary informatio

The Static and Dynamic Lattice Changes Induced by Hydrogen Adsorption on NiAl(110)

Static and dynamic changes induced by adsorption of atomic hydrogen on the NiAl(110) lattice at 130 K have been examined as a function of adsorbate coverage. Adsorbed hydrogen exists in three distinct phases. At low coverages the hydrogen is itinerant because of quantum tunneling between sites and exhibits no observable vibrational modes. Between 0.4 ML and 0.6 ML, substrate mediated interactions produce an ordered superstructure with c(2x2) symmetry, and at higher coverages, hydrogen exists as a disordered lattice gas. This picture of how hydrogen interacts with NiAl(110) is developed from our data and compared to current theoretical predictions.Comment: 36 pages, including 12 figures, 2 tables and 58 reference

Impacts of deep-sea mining on microbial ecosystem services

© 2020 The Authors. Limnology and Oceanography published by Wiley Periodicals, Inc. on behalf of Association for the Sciences of Limnology and Oceanography. Interest in extracting mineral resources from the seafloor through deep-sea mining has accelerated in the past decade, driven by consumer demand for various metals like zinc, cobalt, and rare earth elements. While there are ongoing studies evaluating potential environmental impacts of deep-sea mining activities, these focus primarily on impacts to animal biodiversity. The microscopic spectrum of seafloor life and the services that this life provides in the deep sea are rarely considered explicitly. In April 2018, scientists met to define the microbial ecosystem services that should be considered when assessing potential impacts of deep-sea mining, and to provide recommendations for how to evaluate and safeguard these services. Here, we indicate that the potential impacts of mining on microbial ecosystem services in the deep sea vary substantially, from minimal expected impact to loss of services that cannot be remedied by protected area offsets. For example, we (1) describe potential major losses of microbial ecosystem services at active hydrothermal vent habitats impacted by mining, (2) speculate that there could be major ecosystem service degradation at inactive massive sulfide deposits without extensive mitigation efforts, (3) suggest minor impacts to carbon sequestration within manganese nodule fields coupled with potentially important impacts to primary production capacity, and (4) surmise that assessment of impacts to microbial ecosystem services at seamounts with ferromanganese crusts is too poorly understood to be definitive. We conclude by recommending that baseline assessments of microbial diversity, biomass, and, importantly, biogeochemical function need to be considered in environmental impact assessments of deep-sea mining

Magnetic effects at the interface between nonmagnetic oxides

The electronic reconstruction at the interface between two insulating oxides can give rise to a highly-conductive interface. In analogy to this remarkable interface-induced conductivity we show how, additionally, magnetism can be induced at the interface between the otherwise nonmagnetic insulating perovskites SrTiO3 and LaAlO3. A large negative magnetoresistance of the interface is found, together with a logarithmic temperature dependence of the sheet resistance. At low temperatures, the sheet resistance reveals magnetic hysteresis. Magnetic ordering is a key issue in solid-state science and its underlying mechanisms are still the subject of intense research. In particular, the interplay between localized magnetic moments and the spin of itinerant conduction electrons in a solid gives rise to intriguing many-body effects such as Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions, the Kondo effect, and carrier-induced ferromagnetism in diluted magnetic semiconductors. The conducting oxide interface now provides a versatile system to induce and manipulate magnetic moments in otherwise nonmagnetic materials.Comment: Nature Materials, July issu

Changing Practices in the Use of Continuous Sedation at the End of Life: A Systematic Review of the Literature

Context: The use of continuous sedation until death (CSD) has been highly debated for many years. It is unknown how the use of CSD evolves over time. Reports suggest that there is an international increase in the use of CSD for terminally ill patients. Objective: To gain insight in developments in the use of CSD in various countries and subpopulations. Methods: We performed a search of the literature published between January 2000 and April 2020, in PubMed, Embase, CINAHL, PsycInfo, and the Cochrane Library by using the Preferred reporting items for systematic review and meta-analysis protocols guidelines. The search contained the following terms: continuous sedation, terminal sedation, palliative sedation, deep sedation, end-of-life sedation, sedation practice, and sedation until death. Results: We found 23 articles on 16 nationwide studies and 38 articles on 37 subpopulation studies. In nationwide studies on frequencies of CSD in deceased persons varied from 3% in Denmark in 2001 to 18% in The Netherlands in 2015. Nationwide studies indicate an increase in the use of CSD. Frequencies of CSD in the different subpopulations varied too widely to observe time trends. Over the years, more studies reported on the use of CSD for nonphysical symptoms including fear, anxiety, and psycho-existential distress. In some studies, there was an increase in requests for sedation of patients from their families. Conclusions: The frequency of CSD seems to increase over time, possibly partly because of an extension of indications for sedation, from mainly physical symptoms to also nonphysical symptoms