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Sequential optimality conditions play a major role in proving stronger global convergence results of numerical algorithms for nonlinear programming. Several extensions are described in conic contexts, in which many open questions have arisen. In this paper, we present new sequential optimality conditions in the context of a general nonlinear conic framework, which explains and improves several known results for specific cases, such as semidefinite programming, second-order cone programming, and nonlinear programming. In particular, we show that feasible limit points of sequences generated by the augmented Lagrangian method satisfy the so-called approximate gradient projection optimality condition and, under an additional smoothness assumption, the so-called complementary approximate Karush–Kuhn–Tucker condition. The first result was unknown even for nonlinear programming, and the second one was unknown, for instance, for semidefinite programming.

The constraint nondegeneracy condition is one of the most relevant and useful constraint qualifications in nonlinear semidefinite programming. It can be characterized in terms of any fixed orthonormal basis of the, let us say, $\ell$-dimensional kernel of the constraint matrix, by the linear independence of a set of $\ell(\ell+1)/2$ derivative vectors. We show that this linear independence requirement can be equivalently formulated in a smaller set, of $\ell$ derivative vectors, by considering all orthonormal bases of the kernel instead. This allows us to identify that not all bases are relevant for a constraint qualification to be defined, giving rise to a strictly weaker variant of nondegeneracy related to the global convergence of an external penalty method. We use some of these ideas to revisit an approach of Forsgren [Math. Prog. 88, 105--128, 2000] for exploiting the sparsity structure of a transformation of the constraints to define a constraint qualification, which led us to develop another relaxed notion of nondegeneracy using a simpler transformation. If the zeros of the derivatives of the constraint function at a given point are considered, instead of the zeros of the function itself in a neighborhood of that point, we obtain an even weaker constraint qualification that connects Forsgren's condition and ours., 17 pages, 1 figure. Some results have been revised. GS-nondegeneracy added

The optimization literature is vast in papers dealing with improvements on the global convergence of augmented Lagrangian schemes. Usually, the results are based on weak constraint qualifications, or, more recently, on sequential optimality conditions obtained via penalization techniques. In this paper, we propose a somewhat different approach, in the sense that the algorithm itself is used in order to formulate a new optimality condition satisfied by its feasible limit points. With this tool at hand, we present several new properties and insights on limit points of augmented Lagrangian schemes, in particular, characterizing the strongest possible global convergence result for the safeguarded augmented Lagrangian method.

Through advanced experimental techniques on CrI$_{3}$ single crystals, we derive a previously not discussed pressure-temperature phase diagram. We find that $T_{c}$ increases to $\sim$ 66\,K with pressure up to $\sim$ 3\,GPa followed by a decrease to $\sim$ 10\,K at 21.2\,GPa. The experimental results are reproduced by theoretical calculations based on density functional theory where electron-electron interactions are treated by a static on-site Hubbard U on Cr 3$d$ orbitals. The origin of the pressure induced reduction of the ordering temperature is associated with a decrease of the calculated bond angle, from 95$^{\circ}$ at ambient pressure to $\sim$ 85$^{\circ}$ at 25\,GPa. Above 22\,GPa, the magnetically ordered state is essentially quenched, possibly driving the system to a Kitaev spin-liquid state at low temperature, thereby opening up the possibility of further exploration of long-range quantum entanglement between spins. The pressure-induced semiconductor-to-metal phase transition was revealed by high-pressure resistivity that is accompanied by a transition from a robust ferromagnetic state to gradually more dominating anti-ferromagnetic interactions and was consistent with theoretical modeling.

MnNb3S6 is a monoaxial chiral magnet and stabilizes magnetic solitons in the presence of a magnetic field ( H). The number of solitons can be controlled by varying H. Furthermore, MnNb3S6 exhibits magnetization relaxation due to soliton annihilation, that is, a nonequilibrium chiral soliton lattice (CSL) state. In this study, we observed soliton locking phenomena in a CSL state on bulk MnNb3S6 crystal, as on micro-processed crystals of CrNb3S6. Thus, we could create nonequilibrium and equilibrium CSL states and switch between them. A numerical simulation revealed that the soliton number was preserved in the soliton locking region; thus, magnetization relaxation was not observed.

In [R. Andreani, G. Haeser, L. M. Mito, H. Ram\'irez C., Weak notions of nondegeneracy in nonlinear semidefinite programming, arXiv:2012.14810, 2020] the classical notion of nondegeneracy (or transversality) and Robinson's constraint qualification have been revisited in the context of nonlinear semidefinite programming exploiting the structure of the problem, namely, its eigendecomposition. This allows formulating the conditions equivalently in terms of (positive) linear independence of significantly smaller sets of vectors. In this paper we extend these ideas to the context of nonlinear second-order cone programming. For instance, for an $m$-dimensional second-order cone, instead of stating nondegeneracy at the vertex as the linear independence of $m$ derivative vectors, we do it in terms of several statements of linear independence of $2$ derivative vectors. This allows embedding the structure of the second-order cone into the formulation of nondegeneracy and, by extension, Robinson's constraint qualification as well. This point of view is shown to be crucial in defining significantly weaker constraint qualifications such as the constant rank constraint qualification and the constant positive linear dependence condition. Also, these conditions are shown to be sufficient for guaranteeing global convergence of several algorithms, while still implying metric subregularity and without requiring boundedness of the set of Lagrange multipliers., Comment: 21 pages. Corrections

The intermetallic compound Fe[Formula: see text]Co[Formula: see text]Si has a helical magnetic order for [Formula: see text], whereas its orbital angular momentum contributing to the occurrence of a Dzyaloshinskii–Moriya interaction has not yet been verified. We applied soft x-ray magnetic circular dichroism spectroscopy on the Fe [Formula: see text] and Co [Formula: see text] edges below [Formula: see text] for Fe[Formula: see text]Co[Formula: see text]Si such that their orbital magnetic moments [Formula: see text] were evaluated independently. The dichroic signals provide direct experimental evidence that [Formula: see text] for both Fe and Co is coupled in a parallel manner with each spin counterpart [Formula: see text]. The ratio of [Formula: see text] to [Formula: see text] is independently estimated as [Formula: see text]/[Formula: see text]% for Fe and 9% for Co. By comparing the average of the two [Formula: see text] values with the saturated magnetization using a commercial superconducting quantum interference device (SQUID) magnetometer, the hole number in the [Formula: see text] bands for both Fe and Co is roughly estimated as approximately 1.5. This suggests that Fe and Co should be arranged closely for stabilizing the ferromagnetic moments.

The constant rank constraint qualification, introduced by Janin in 1984 for nonlinear programming, has been extensively used for sensitivity analysis, global convergence of first- and second-order algorithms, and for computing the derivative of the value function. In this paper we discuss naive extensions of constant rank-type constraint qualifications to second-order cone programming and semidefinite programming, which are based on the Approximate-Karush-Kuhn-Tucker necessary optimality condition and on the application of the reduction approach. Our definitions are strictly weaker than Robinson's constraint qualification, and an application to the global convergence of an augmented Lagrangian algorithm is obtained., Comment: An older version of this paper was separated in two, and SDP was included here. The first part can be found here: https://www.ime.usp.br/~ghaeser/nota-crcq-errata.pdf

In this work, we present an Augmented Lagrangian algorithm for nonlinear semidefinite problems (NLSDPs), which is a natural extension of its consolidated counterpart in nonlinear programming. This method works with two levels of constraints; one that is penalized and other that is kept within the subproblems. This is done to allow exploiting the subproblem structure while solving it. The global convergence theory is based on recent results regarding approximate Karush–Kuhn–Tucker optimality conditions for NLSDPs, which are stronger than the usually employed Fritz John optimality conditions. Additionally, we approach the problem of covering a given object with a fixed number of balls with a minimum radius, where we employ some convex algebraic geometry tools, such as Stengle’s Positivstellensatz and its variations, which allows for a much more general model. Preliminary numerical experiments are presented.

Este trabalho é focado num problema clássico das Ciências e Engenharia, que consiste em cobrir um objeto por esferas de mesmo raio, a ser minimizado. A abordagem prática usual conta com sérias desvantagens. Logo, faz-se necessário trabalhar com isto de forma diferenciada. A técnica proposta aqui envolve a utilização de resultados célebres da geometria algébrica real, que tem como peça central o positivstellensatz de Stengle e, fazendo a devida relação entre esses resultados e otimização com restrições envolvendo representações naturais por somas de quadrados, é possível reduzir o problema original a um de programação semidefinida não linear. Mas, por contar com particularidades que favorecem a aplicação do paradigma de restauração inexata, esta foi a técnica utilizada para resolvê-lo. A versatilidade da técnica e a possibilidade de generalização direta dos objetos envolvidos destacam-se como grandes vantagens desta abordagem, além da visão algébrica inovadora do problema. This work is focused on a classic problem from Engineering. Basically, it consists of finding the optimal positioning and radius of a set of equal spheres in order to cover a given object. The common approach to this carries some substantial disadvantages, what makes it necessary to nd a dierent way. Here, we explore some renowned results from real algebraic geometry, which has Stengle\'s positivstellensatz as one of its central pieces, and SOS optimization. Once the proper link is made, the original problem can be reduced to a nonlinear semidenite programming one, which has peculiarities that favours the application of an inexact restoration paradigm. We point out the algebraic view and the no use of discretizations as great advantages of this approach, besides the notable versatility and easy generalization in terms of dimension and involved objects.

The conventional global model of heat transfer for the Czochralski (CZ) crystal growth of oxides is based on a pseudo-steady axisymmetric assumption. However, because oxide melt flow is commonly three-dimensional and unsteady, an approach to formulate a global model in which a three-dimensional unsteady melt flow is taken into account was proposed in this study. This approach couples a conventional global model of heat transfer and a model of a three-dimensional, unsteady melt flow using two interface models. The newly developed global model was validated and used to investigate the effect of a three-dimensional, unsteady melt flow on oxide crystal growth. The results indicate that the effect of a three-dimensional, unsteady melt flow is too large to be neglected when the crystal rotational Reynolds number is relatively large. It was found that a three-dimensional, unsteady melt flow shifts the critical Reynolds number at which interface inversion occurs at a much lower value than that obtained using a conventional model based on a pseudo-steady axisymmetric assumption.

Fetal hepatocytes were harvested at day 20 of gestation from spontaneously hypertensive rats (SHR) and then transplanted into recipient adult SHR spleens. Morphological examination of the recipient spleens revealed that, after 4 and 10 wk, large masses of hepatocytes were present in the red pulp with apparent cord-like structures. Larger batches of hepatocytes were observed in the spleens at 10 wk after than at 4 wk after transplantation. Of major significance was the fact that hepatocyte transplanted spleens were able to express several families of cytochrome P450 (cyto P450) proteins 2–10 wk after transplantation. Immunochemical determinations revealed that cytos P450 IA1, P450 IIB1, P450 p, P450 HLp, and P450 LAto could be detected without any prior induction. All were intensely expressed 6 wk after transplantation; however, P450 IA1 and P450 IIB1 did not appear to be expressed by 2 wk after transplantation. Although cytos P450 p and P450 HLp did not appear to be expressed by 10 wk after transplantation, they were induced with dexamethasone at that time. Cyto P450 LAω and peroxisomal acyl CoA oxidase were expressed 6 wk after transplantation in a 70% hepatectomized host. These results demonstrate that fetal hepatocytes can be successfully transplanted into the spleens of recipients and that the fetal hepatocytes appear to grow and develop cyto P450 metabolizing systems.

A prospective randomised multicentre clinical study was undertaken for 2 years and 3 months from November 1982, with the aim of examining the significance of using a combination of ftorafur (FT) and tamoxifen (TAM) for post-operative adjuvant therapy of breast cancer. Patients had either stage II or stage IIIa disease, were age 75 or below and had undergone radical mastectomy. Patients were divided into two groups and received one of the following treatment protocols: treatment A, intravenous administration of doxorubicin (DOX), 20 mg on the day of surgery and 10 mg the next day, followed by oral FT 50 mg day-1 for 2 years from the 14th day; treatment B, the same pattern of DOX administration for the first 2 days, followed by a combined therapy of FT and TAM 20 mg day-1 for 2 years. The number of patients was 546 (treatment A 274 and treatment B 272), of whom 34 (6%) were ineligible. The remaining 512 patients (treatment A 254 and treatment B 258) were followed up for 5 years for analysis. Significantly higher 5 year disease-free rate and 5 year survival rates were observed with treatment B compared with treatment A. When seen in terms of background factors, node-positive patients appeared to derive more benefit from tamoxifen than node-negative patients, but the oestrogen receptor-negative and premenopausal subgroups appeared to derive about the same benefit as those who were oestrogen receptor positive and post-menopausal. Indeed, survival in the premenopausal group was significantly better with tamoxifen (P = 0.04). No increase in side-effects was seen by combining TAM with FT. The study results demonstrate that concomitant administration of FT and TAM is better than FT alone for post-operative adjuvant therapy for breast cancer.

A protocol control system architecture that provides very high processing performance for gigabit-per-second data communication in a broadband network is described. The architecture connects protocol controllers in parallel and uses a distributed multilink method that features a distributed algorithm for allocating transmission on the transmitting side and a resequencing algorithm on the receiving side. The system performance and the influence of transmission errors caused by cell loss in an asynchronous transfer mode network are evaluated. It is shown that by reducing each controller's distributing overhead, the system increases throughput up to 90 times that achieved when using a single controller. >

Intraperitoneal transplantation of hepatocytes encapsulated with calcium alginate gel produced a marked improvement in the survival rate (75%) of rats with D-galactosamine (D-gal)-induced acute hepatic failure (AHF) when compared to the rate of 50% in rats undergoing free hepatocyte transplantation (HCTX). The viability of encapsulated hepatocytes was still 70% at 36 h after transplantation, and a gradual improvement in the serum glutamic oxaloacetic transaminase (GOT) and total bilirubin values was observed after encapsulated HCTX. Moreover, the arterial blood ketone body ratio (AKBR) remained within the normal range for the whole period of the investigation (60 h after transplantation), and histological investigation of the liver at 36 h demonstrated only slight inflammatory cell infiltrates without hepatocellular necrosis. The phagocytic index rose immediately after encapsulated HCTX and remained high subsequently. A prostaglandin inhibitor, indomethacin, blocked the improvement in survival rate, serum GOT, and AKBR of rats with D-gal-induced AHF despite encapsulated HCTX. Furthermore, no increase in the phagocytic index was observed. Indomethacin apparently suppressed the activation of Kupffer cells by encapsulated HCTX, which then failed to improve the survival of rats with D-gal-induced acute hepatic failure. Our results indicate that the reticuloendothelial system seems to play an important role in the efficacy of encapsulated HCTX in rats with D-gal-induced AHF.

Ion and Electron Beam irradiation effects for Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O superconducting thin films are investigated. By measuring ion and electron dose dependencies of resistivity versus temperature, it became clear that the crystal structure of a Bi system thin film is destroyed with a lower ion and electron dose, than for a Y system thin film. Moreover, it is conformed that the superconducting characteristics for ion and electron beam irradiated films, are recovered by annealing in an O2, atmosphere.

We have developed a high-pressure clamp cell made of Cu-Ti alloy, which can be equipped to a Quantum Design MPMS SQUID magnetometer. The precise magnetic measurements is possible by using this clamp cell. We have discovered that the structural change of organic radical, galvinoxyl is suppressed by pressurization. Magnetic and thermal properties under pressure have been examined. This compound under 7 kbar is a quasione-dimensional Heisenberg ferromagnet with 2J/kB≈20K. Interchain interaction is antiferromagnetic and a three-dimensional antiferromagnetic phase transition is observed at 0. 72 K.

This chapter reviews various typical pressure effects on genuine organic magnetic compounds. The artificial control of the overlapping of π-orbitals under the pressure gives one of the effective ways to investigate the electronic state and the mechanism of intermolecular interactions. The value of the hydrostatic pressure at low temperatures is obtained from the pressure dependence of the superconducting transition temperature of a superconducting metal, such as Sn or Al, that is placed in the pressure cell, and its transition temperature is detected by the coil system in the magnetic susceptibility measurements. The unpaired electrons are expected to delocalize over a wider space within the larger molecules, and the overlap of the π-orbitals or the transfer integrals is considered to be more susceptible under the pressure. The pressure effects on the ferromagnetic interaction intermediated by the β-hydrogen of a methyl group are explained. The investigation of the pressure dependence of the magnetization allows one to determine the averaged variation of the intermolecular interactions. The pressure effects on sulfur-based organic magnets with ferromagnetic moments are elaborated in the chapter.

Due to the increase of OPGW cable use in Brazil and considering the restrictions of the Brazilian National Operation System to disconnect the overhead transmission lines, manufacturers and utilities have developed technologies and construction works to remove the conventional existent ground wires replacing them by OPGW cables, with energized line. One of the fastest and safest alive line installation technology, particularly for 500 kV lines, is the "carrier method" developed by Fujikura Ltd. The method consists by using a self-propelled carrier, special aramide ropes and double pulleys and the average productivity of cable installation is 60 km/month per team. This paper describes the method, the tools, the training of construction teams for OPGW installation in alive-lines. The "carrier method" was successfully used in Brazil in the CHESF transmission line system, and about 300 km of OPGW cable using this method were installed.

We have measured the specific heat of an S = 1/2 antiferromagnetic alternating Heisenberg chain pentafulorophenyl nitronyl nitroxide in magnetic fields up to HH(C2). This compound has a field-induced magnetic ordered (FIMO) phase between H(C1) and H(C2). Characteristic behaviors are observed depending on the magnetic field up to above H(C2) outside of the H-T boundary for the FIMO. The temperature and field dependence of the specific heat are qualitatively in good agreement with the theoretical calculation on an S = 1/2 two-leg ladder [Wang et al., Phys. Rev. Lett. 84, 5399 (2000)]]. This agreement suggests that the observed behaviors are related with the low-energy excitation in the Tomonaga-Luttinger liquid.

A protocol control system architecture that provides excellent processing performance for data communications and utilizes a high speed network such as asynchronous transfer mode (ATM) is discussed. The system consists of multiple protocol controllers (PCs) connected in parallel and employs the distributed multilink method, in which the multilink procedure is distributed to each PC. The method features a distributed algorithm for transmission allocation at the transmitting side and a resequence algorithm at the receiving side. Characteristics of the method are analyzed and the system performance is evaluated. The system can provide a 90-fold performance improvement over a single PC. >

The service specific connection oriented protocol is now being studied for use as the ATM adaptation layer protocol for connection oriented data communication and UNI/NNI signaling in the B-ISDN. The key feature of this protocol is a numbered poll mechanism that enables status information to be exchanged frequently and that is helpful for selective retransmission for frame loss. This paper examines this mechanism from the viewpoints of polling interval and frame length. Because this protocol was designed to perform selective retransmission for error recovery, some requirements, such as saving buffer, are not met. Two enhancements are therefore proposed: one consists of a Go-back-N-like procedure and nonassured credit, and the other is an SD PDU with a P bit. Guidelines to determine the POLL PDU interval are given. >

A trial was designed to examine the combination of UFT and mitomycin (Mutamycin) plus tamoxifen (Nolvadex) as postoperative adjuvant therapy in the treatment of patients with stage II, estrogen receptor (ER)-positive primary breast cancer. Mitomycin was administered intravenously at 13 mg/m2 on the day of surgery. Patients judged to be ER-positive were randomly allocated to either group A, which received oral tamoxifen 20 mg/day 14 days after surgery for 2 years, or group B, receiving oral UFT 400 mg/day plus tamoxifen 20 mg/day. A total of 219 patients were enrolled in group A, of which 213 (97.3%) were determined to be eligible; 225 patients enrolled in group B and 223 (99.1%) were eligible. The 5-year survival rates were 93.0% for group A and 95.4% for group B, with no significant difference between groups. The 5-year relapse-free survival rates were 83.1% for group A and 90.7% for group B, a significant advantage (P = .020) for the UFT plus tamoxifen group. Combination therapy with mitomycin, tamoxifen, and UFT proved to be an effective postoperative chemoendocrine therapy for stage II, ER-positive breast cancer.

Hepatocytes isolated from F344 rats were transplanted into the spleens of congenic Nagase analbuminemic rats (NARs). The morphology and function of the transplanted hepatocytes were investigated after 18 months. The hepatocytes had formed nodules that occupied approximately 35% of the area of the splenic parenchyma on microscopic examination. Ultrastructural examination demonstrated that the organelles of the transplanted cells were indistinguishable from those of normal hepatocytes. The serum albumin level in NARs at 18 months after intrasplenic transplantation (HCTx) was about 3.6 % of that in normal rats. We confirmed that the hepatocytes in the spleen produced albumin and increased the serum albumin level in NARs with HCTx. The NAR model demonstrates the effect of HCTx and prolonged changes in the morphology of the hepatized spleen.

The Role of Organ Transplant Network are the encouragement of the organ transplantation and fair organ sharing. Its principled are united, neutral open and nonprofit organization, so as to secure the fair and quick organ sharing based on the uniform allocation policy. Japan Kidney Transplant Network was established in 1995 nad reorganized into multi-organ sharing network, Japan Organ Transplant Network in 1997, when Japan Organ transplant Act was enacted. It consists of transplant coordinators, physicians, transplant surgeons, kidney banks, local administration, academic standings, other organization/associations and others. There are several committee, in which special subjects on organ transplantation and related matters are consulted, and review system in which each case is assessed and judged. And principal and essential items are decided by the board of members and then by the general assembly. The new computer system was introduced and registrants data are renewed every year, and recipient selection is done based on the latest registrants data. Standardized HLA examination tray was introduced and class II antigen was examined by means of DNA typing since 1997, which enabled more precise and accurate search. Hereafter, the education and encouragement of transplant coordinators to raise themselves and the more effective and extended distribution of donor cards are indispensable to promote organ donation/transplantation.

The expression and enzymatic activity of the cytochrome P450 LAomega within intrasplenically transplanted hepatocytes was investigated.Fetal hepatocytes were harvested from spontaneously hypertensive rats and transplanted into recipient adult spontaneously hypertensive rat spleens.Microscopic examination revealed masses of hepatocytes in the red pulp. Immunochemical studies detected cytochrome P450 LAomega in transplanted hepatocytes by 6 and 10 weeks after transplantation. Cytochrome P450 LAomega mRNA accumulates at 6 weeks after transplantation. Cytochrome P450-arachidonic acid omega/omega-1 hydroxylase activity (formation of 20/19-hydroxyeicosatetraenoic acid) was detected at 10 weeks after transplantation.These results demonstrated that fetal hepatocytes grow in the spleen and function similarly to adult hepatocytes.

We report the advantage of employing transanal endoscopic microsurgery (TEM) using the contact Nd:YAG laser for the treatment of a rectal anastomotic stenosis. A 72-year-old woman was admitted to our hospital with a postoperative rectal anastomotic stenosis. Twenty months prior to admission, the patient underwent a low anterior resection for the treatment of the rectal cancer using an EEA stapling device. A barium enema and colonoscopy revealed a rectal stenosis, 0.8-cm diameter. This stenosis was at the anastomotic site, approximately 4.0 from the dental line. An endoscopic treatment was performed transanally using the contact Nd:YAG laser. The stenotic rectal wall was fulgurated or vaporized completely. There were no intraoperative or postoperative complications. We concluded that TEM appears to be a safe and minimally invasive procedure. Furthermore, the contact Nd:YAG laser is very effective in treating the gastrointestinal stenotic area. To our knowledge, this is the first successful report of this novel procedure.

Laparoscopic cholecystectomy (LC) has become the standard treatment for removing a diseased gallbladder. Endoscopic surgical techniques are used to perform appendectomies, bowel resections, and gastrectomies. This minimally invasive surgery is favored because it decreases the patients' postoperative pain and length of hospitalization. However the incidence of complications with this technique is not negligible. As a new technique is evolving, the potential for complications is high. This increase in complication rate is undoubtedly due to inexperience during the initial phase of the surgeon's learning curve. Demand for the procedure has required rapid training and credentialing of many surgeons with limited experience in endoscopy and the use of instruments that allow only limited viewing of abdominal structures.

We encountered a patient with congenital platelet cyclo-oxygenase deficiency with normal ability to synthesize vascular prostaglandin I2 (PGI2) and thromboxane A2 (TXA2). The patient's peripheral blood monocytes did not show cyclo-oxygenase (COX) activity, but cultured bone marrow fibroblasts showed COX activity. To determine the mechanism of primary hemostasis in this patient, we examined the effect of oral administration of aspirin (1 g) on bleeding time and thromboxane B2 (TXB2), 6-keto prostaglandin F1 alpha (6-keto-PGF1 alpha) production in the blood emerging from the incision in this patient. The bleeding time was markedly prolonged by the administration of aspirin, and this prolongation was associated with the inhibition of TXB2 in the effluent blood, which seemed to be derived from the vessel wall. These findings suggest that vascular TXA2 production plays an important role in the maintenance of hemostasis.

We report on a patient with colon cancer and a very high serum alpha-fetoprotein level. This 75-yr-old man presented with right lower quadrant abdominal pain. An abdominal CT scan as well as ultrasonography showed a tumor in the cecum. Serum alpha-fetoprotein level was extremely high (3,070 ng/ml). At laparotomy, a large mass was found in the cecum, and a right hemicolectomy was performed. Histological examination, including immunohistochemical study, showed an adenocarcinoma of the colon producing alpha-fetoprotein.

We studied protective effects of dibutyryl cyclic AMP (DBcAMP 15 mg/kg i.p.) and OK-432 (5 KE/body), and the role of the spleen on D-galactosamine (D-Gal 500 mg/kg i.p.) and lipopolysaccharide (endotoxin: Et 0.5 mg/kg i.p.) induced acute liver failure. The survival rates were 10% in the control group (D-Gal+Et), 53% in the group I A (DBcAMP was administered at 1 hour before D-Gal administration), 79% in the group I B (Splenectomy was performed at 24 hours before D-Gal administration on the group I A), 87% in the group II A (OK-432 was administered at 24 hours before D-Gal administration), and 64% in the group II B (Splenectomy was performed at 24 hours before D-Gal administration on the group II A). GOT activities and TNF activities were significantly improved in the treatment groups, and in the group I B and group II A, they were more improved than in the group I A and group II B. In conclusion, spleen had the positive effect for OK-432 treatment, and also had the negative effect for DBcAMP treatment on acute liver failure induced by D-Gal and Et.

The purpose of this study was to investigate suitable sites for hepatocyte transplantation in rats with congenital liver enzyme deficiency. Hepatocytes were isolated from ODS-(+)/+ rats, which are congenic to ODS-od/od rats and have hepatic L-gulonolactone oxidase. A total of 1 x 10(7), 1 x 10(7), and 2.5 x 10(6) hepatocytes were respectively transplanted into the peritoneal cavity, spleen, or portal vein of ODS-od/od rats, which are unable to synthesize ascorbic acid (AsA) due to lack of hepatic L-gulonolactone oxidase. After 4 days of oral pretreatment with 0.05% 2-acetylaminofluorene, recipients underwent 70% partial hepatectomy just before transplantation. AsA administration was discontinued at 6 weeks after transplantation. The symptom-free survival rate and the serum AsA level of recipient rats were determined at 6 weeks after discontinuing AsA administration. The symptom-free survival rate of untransplanted rats and recipient rats with intraperitoneal, intrasplenic and intraportal hepatocyte transplantation were 0%, 0%, 60%, and 100%, respectively. The serum AsA levels were 0.20 +/- 0.20 microgram/ml, 0.14 +/- 0.05 microgram/ml, 1.06 +/- 0.26 microgram/ml, and 1.58 +/- 0.61 microgram/ml, respectively. Intrasplenic or intraportal transplantation was able to cure ODS-od/od rats. A subsequent splenectomy study showed that hepatocytes reaching the liver via the splenic vein following intrasplenic hepatocyte transplantation played a major role in this experimental success.