A frameshift mutation in NOD2 associated with susceptibility to Crohn's disease

Crohn's disease is a chronic inflammatory disorder of the gastrointestinal tract, which is thought to result from the effect of environmental factors in a genetically predisposed host. A gene location in the pericentromeric region of chromosome 16, IBD1, that contributes to susceptibility to Crohn's disease has been established through multiple linkage studies, but the specific gene(s) has not been identified. NOD2, a gene that encodes a protein with homology to plant disease resistance gene products is located in the peak region of linkage on chromosome 16 (ref. 7). Here we show, by using the transmission disequilibium test and case-control analysis, that a frameshift mutation caused by a cytosine insertion, 3020insC, which is expected to encode a truncated NOD2 protein, is associated with Crohn's disease. Wild-type NOD2 activates nuclear factor NF-kappaB, making it responsive to bacterial lipopolysaccharides; however, this induction was deficient in mutant NOD2. These results implicate NOD2 in susceptibility to Crohn's disease, and suggest a link between an innate immune response to bacterial components and development of disease.

Biodegradable polymers for ocular drug delivery

A variety of ocular drug delivery systems, including a controlled release of the drug, drug targeting, and penetration enhancement of the drug, have been investigated. Biodegradable polymers have been widely used as the drug carrier for controlled-release systems. Biodegradable polymers release the drug as they themselves degrade and are finally absorbed within the body. Several ocular drug delivery systems using different kinds of biodegradable polymers have been studied. In this article, we describe the fundamental mechanisms of drug delivery systems, polymer erosion and drug release, and then review those systems using the most popular biodegradable polymers, poly(lactic acid) and poly(lactic-glycolic acid).

Wavelength-multiplexing diffractive phase elements: design, fabrication, and performance evaluation

We report on the wavelength-multiplexing diffractive phase element (WMDPE) capable of generating independent spot patterns for different wavelengths. The iterative method proposed by Bengtsson [Appl. Opt. 37, 1998] for designing a kinoform that produces different patterns for two wavelengths is extended to the WMDPE for multiple wavelengths (more than two wavelengths). Effectiveness of the design algorithm is verified by design and computer simulations on the WMDPE's for four and nine wavelengths. The WMDPE for three wavelengths (441.6, 543.5, and 633 nm) is designed with five phase levels and is fabricated by electron-beam lithography. We observed that the individual spot patterns are reconstructed for the design wavelengths correctly. Performance of the WMDPE is evaluated by computer simulations on the uniformity error, the light efficiency, and the contrast. On the basis of the results, the characteristics of the WMDPE's are discussed in terms of various conditions of fabrication and usage.

Favorable quality of life after repeat hepatic resection for recurrent hepatocellular carcinoma

BACKGROUND/AIMS

The appropriate choice of treatment for recurrent hepatocellular carcinoma after hepatic resection remains controversial. The aim of this study is to clarify prognostic factors and quality of life in patients with tumor recurrence after hepatic resection for hepatocellular carcinoma.

METHODOLOGY

We retrospectively analyzed 188 patients with hepatocellular carcinoma who underwent curative hepatic resection between 1988 and 1997. Statistical analysis was performed to identify prognostic factors involved after recurrence. Furthermore, quality of life after treatment for recurrence was compared between patients with repeat hepatic resection or hepatic arterial infusion chemotherapy.

RESULTS

In 123 patients with recurrence, unfavorable predictors after recurrence are pTNM Stage III/IV at initial surgery, receiving chemotherapy before initial surgery and presence of extrahepatic recurrence. In contrast, favorable predictors are 3 years or more of disease-free interval and repeat hepatic resection. The incidence of deteriorated performance status in the repeat hepatic resection group was lower than in the hepatic arterial infusion chemotherapy group because of better psychological function in patients undergoing repeat hepatic resection.

CONCLUSIONS

Repeat hepatic resection provides a good prognosis and a favorable quality of life in patients with recurrence after hepatic resection for hepatocellular carcinoma.

Hepatocyte growth factor promotes liver regeneration and protein synthesis after hepatectomy in cirrhotic rats

BACKGROUND/AIMS

Hepatocyte growth factor, a potent mitogen for hepatocytes has been reported to be a hepatrophic factor in normal livers. In this study, the effect of exogenous hepatocyte growth factor on liver regeneration in cirrhotic rats was investigated, in vitro and in vivo.

METHODOLOGY

Liver cirrhosis was induced by intraperitoneal injections of an emulsion, carbon tetrachloride and olive oil, twice weekly for 10 weeks. In vitro, various amounts of exogenous hepatocyte growth factor; 0, 0.5, 1, 2.5, 5, and 10 ng/mL; were added to the hepatocytes isolated using in situ perfusion method. In vivo, partial hepatectomy (Hx), according to the procedure described by Higgins and Anderson, was performed on cirrhotic rats. Saline solution (control group) or 3 micrograms/kg of exogenous hepatocyte growth factor (HGF group) was then injected through the tail vein at intervals 12 hours after Hx.

RESULTS

In vitro, DNA synthesis in hepatocytes obtained from cirrhotic livers increased following exogenous hepatocyte growth factor in dose-dependent fashion. In vivo, the labeling index of 5-bromo-2'-deoxyuridine at 24 hours after Hx was markedly increased by exogenous hepatocyte growth factor (control, 10.0 +/- 3.1%; hepatocyte growth factor, 25.8 +/- 9.8%; P < 0.01). Furthermore, serum albumin at 24 and 72 hours and a normotest at 24 hours after Hx, were significantly higher in the HGF group than in the control group.

CONCLUSIONS

These results indicate that exogenous hepatocyte growth factor may promote DNA synthesis and protein synthesis during liver regeneration after Hx with cirrhosis.

Utility of Tc-99m GSA whole-body scintigraphy in detecting bone metastases from hepatocellular carcinoma

Recent advances in the treatment of hepatocellular carcinoma (HCC) have prolonged patient survival. However, the number of patients with bone metastases identified during follow-up examinations has increased. Tc-99m Sn-N-pyridoxy-5-methyltryptophan (Tc-99m PMT) has been reported to accumulate at a high rate in HCC lesions and bone metastases. In the patient described here, whole-body scintigraphy showed accumulation of DTPA galactosyl human serum albumin (Tc-99m GSA) and Tc-99m PMT in bone metastases from HCC. The authors suggest that asialoglycoprotein receptors may be present in bone metastases from well-differentiated HCC. Tc-99m GSA whole-body imaging can be used to detect bone metastases from HCC and to evaluate hepatic reserve.

Nod2, a Nod1/Apaf-1 family member that is restricted to monocytes and activates NF-kappaB

Apaf-1 and Nod1 are members of a protein family, each of which contains a caspase recruitment domain (CARD) linked to a nucleotide-binding domain, which regulate apoptosis and/or NF-kappaB activation. Nod2, a third member of the family, was identified. Nod2 is composed of two N-terminal CARDs, a nucleotide-binding domain, and multiple C-terminal leucine-rich repeats. Although Nod1 and Apaf-1 were broadly expressed in tissues, the expression of Nod2 was highly restricted to monocytes. Nod2 induced nuclear factor kappaB (NF-kappaB) activation, which required IKKgamma and was inhibited by dominant negative mutants of IkappaBalpha, IKKalpha, IKKbeta, and IKKgamma. Nod2 interacted with the serine-threonine kinase RICK via a homophilic CARD-CARD interaction. Furthermore, NF-kappaB activity induced by Nod2 correlated with its ability to interact with RICK and was specifically inhibited by a truncated mutant form of RICK containing its CARD. The identification of Nod2 defines a subfamily of Apaf-1-like proteins that function through RICK to activate a NF-kappaB signaling pathway.

Tyrosine kinase inhibition of multiple angiogenic growth factor receptors improves survival in mice bearing colon cancer liver metastases by inhibition of endothelial cell survival mechanisms

Redundant mechanisms mediate colon cancer angiogenesis. Targeting multiple angiogenic factors simultaneously may improve survival of mice with colon cancer metastases. BALB/c mice underwent splenic injection with CT-26 colon cancer cells to generate liver metastases and received administration of either vehicle alone or a tyrosine kinase inhibitor for vascular endothelial growth factor, basic fibroblast growth factor, and platelet-derived growth factor receptors (SU6668). Mice were sacrificed when they became moribund as determined by a blinded observer. In a parallel experiment, groups of mice were sacrificed at earlier time points to better define the kinetics of the effect of SU6668 on angiogenic parameters over time. SU6668 increased median survival by 58% (P < 0.001) and led to a progressive increase in tumor cell and endothelial cell apoptosis that increased over time. In addition, pericyte vessel coverage and tumor vascularity were significantly decreased in mice treated with SU6668. Based on current knowledge of endothelial cell survival, these data suggest that SU6668 may prevent tumor endothelial cell survival directly (vascular endothelial growth factor) and indirectly (pericyte coverage) by affecting endothelial cell survival mechanisms.

Human Nod1 confers responsiveness to bacterial lipopolysaccharides

The immune response to microbial pathogens is initiated by recognition of specific pathogen components by host cells both at the cell surface and in the cytosol. While the response triggered by pathogen products at the surface of immune cells is well characterized, that initiated in the cytosol is poorly understood. Nod1 is a member of a growing family of intracellular proteins with structural homology to apoptosis regulators Apaf-1/Ced-4 and a class of plant disease-resistant gene products. Here we show that bacterial lipopolysaccharides, but not other pathogen components tested, induced TLR4- and MyD88-independent NF-kappaB activation in human embryonic kidney 293T cells expressing trace amounts of Nod1. Nod2, another Nod family member, also conferred responsiveness to bacterial components but with a response pattern different from that observed with Nod1. As it was reported for plant disease-resistant R proteins, the leucine-rich repeats of Nod1 and Nod2 were required for lipopolysaccharide-induced NF-kappaB activation. A lipopolysaccharide binding activity could be specifically coimmunopurified with Nod1 from cytosolic extracts. These observations suggest that Nod1 and Nod2 are mammalian counterparts of plant disease-resistant gene products that may function as cytosolic receptors for pathogen components derived from invading bacteria.

Optoelectronic parallel-matching architecture: architecture description, performance estimation, and prototype demonstration

We propose an optoelectronic parallel-matching architecture (PMA) that provides powerful processing capabilities in global processing compared with conventional parallel-computing architectures. The PMA is composed of a global processor called a parallel-matching (PM) module and multiple processing elements (PE's). The PM module is implemented by a large-fan-out free-space optical interconnection and a PM smart-pixel array (PM-SPA). In the proposed architecture, by means of the PM module each PE can monitor the other PE's by use of several kinds of global data matching as well as interprocessor communication. Theoretical evaluation of the performance shows that the proposed PMA provides tremendous improvement in global processing. A prototype demonstrator of the PM module is constructed on the basis of state-of-the-art optoelectronic devices and a diffractive optical element. The prototype is assumed for use in a multiple-processor system composed of 4 x 4 PE's that are completely connected through bit-serial optical communication channels. The PM-SPA is emulated by a complex programmable device and a complementary metal-oxide semiconductor photodetector array. On the prototype demonstrator the fundamental operations of the PM module were verified at 15 MHz.

Suppression of lens stalk cell apoptosis by hyaluronic acid leads to faulty separation of the lens vesicle

How the lens vesicle separates normally from the surface ectoderm has not been adequately explained. Apoptosis is an important mechanism that induces tissue development and morphogenesis by physiological cell death during normal development, and hyaluronic acid has been shown to regulate the apoptotic process in various tissues. To elucidate the normal and abnormal processes of lens vesicle separation, we investigated the distribution of apoptotic cells and hyaluronic acid in normal and abnormal lens vesicle development. The offspring from pregnant C57BL/6NJcl mice were removed by laparotomy on days 9, 10, 11, 12, 13, 14, 15, 16 or 18 of gestation. Tissue blocks of the eyes were fixed in 4% paraformaldehyde solution and embedded in paraffin wax. Serial sections of the eye were cut, and sections containing normal lens tissues and spontaneously occurring faulty separation of the lens vesicle were chosen for subsequent procedures. These sections were stained either with TUNEL method for detection of apoptosis or with biotinylated hyaluronic acid binding protein (HABP) for hyaluronic acid. Then TUNEL-positive and HABP-positive reactions in the lens tissues were examined by light microscopy. In normal eye development, the lens stalk connecting the surface ectoderm with the lens vesicle was observed from day 11 through day 12 of gestation, and the lens stalk completely disappeared on day 13 of gestation in this strain. In normally regressive lens stalk, several TUNEL-positive cells were identified, and no positive staining for HABP was seen. However, in spontaneously occurring persistent lens stalk tissues on days 14, 15, 16 and 18 of gestation, no TUNEL-positive cells were detectable, and evident HABP-positive reactions were seen. In eyes on day 12 of gestation with possibly presumed faulty separation of the lens vesicle, no TUNEL-positive cells were detectable and evident HABP-positive reactions were seen in the lens stalk areas. The results indicated that cell death by apoptosis is anatomically closely associated with, appears to be essential for normal regression of the lens stalk, and its failure to occur leads to faulty separation of the lens vesicle. In addition, excessive hyaluronic acid in the lens stalk area may be a possible cause of the lack of apoptosis, inducing its faulty separation.

Effect of particle size of polymeric nanospheres on intravitreal kinetics

In this study, we injected nanospheres containing a fluorescein derivative into the vitreous cavity of pigmented rabbit eyes and evaluated their intraocular kinetics as drug carriers in vivo. Polystyrene nanospheres (2 microm, 200 nm and 50 nm in diameter) containing a fluorescein derivative were used in this study. A suspension of each particle was prepared by diluting with distilled water at a concentration of 10 microg/ml equivalent to sodium fluorescein. The suspension of nanospheres was injected once into the vitreous cavity of unilateral eyes of pigmented rabbits. A sodium fluorescein solution of the same concentration was injected once into the vitreous cavity of the other eye as the control. The intraocular kinetics of nanospheres was evaluated by measuring vitreous fluorescence using a scanning fluorophotometer. To investigate elimination pathways of nanospheres in detail, serial cross-sections of the eyes were examined with a fluorescence microscope. The fluorescence derived from nanospheres was observed in the vitreous cavity for over 1 month (2 microm: t(1/2) = 5.4 +/- 0.8 days, 200 nm: t(1/2) = 8.6 +/- 0.7 days, 50 nm: t(1/2) = 10.1 +/- 1.8 days), whereas that in the control eyes completely disappeared within 3 days (t(1/2) = 7.8 +/- 0.7 h). The elimination half-life from the vitreous cavity correlated well with the particle diameter (r = -0.997, p = 0.007). Histological studies using a fluorescence microscope revealed that nanospheres with a diameter of 2 microm were seen in the vitreous cavity and trabecular meshwork, while nanospheres with a diameter of smaller than 200 nm were also observed in the retina as well as these tissues. Our findings indicated that nanospheres may be beneficial as a drug carrier to the retina, vitreous and trabecular meshwork.

Active drug targeting with immunoconjugates to choroidal neovascularization

PURPOSE

Active drug targeting with monoclonal antibody to neovascular vessels may be a potential treatment for choroidal neovascularization (CNV) in age-related macular degeneration (AMD). Endoglin (CD105) is a proliferating endothelial cell marker with excellent potential for targeting. The goals of this study were to investigate the expression of CD105 in CNV membranes surgically excised from patients with AMD and CNV lesions induced by intense laser photocoagulation in a cynomolgus monkey and to evaluate the in vitro effect of immunoconjugates on endothelial cells.

METHODS

CNV membranes were surgically excised from 10 patients with AMD. Experimental CNV was induced by intense laser photocoagulation in a cynomolgus monkey. Immunolocalization of CD105 on frozen sections of CNV lesions was studied by immunohistochemical evaluation. Anti-von Willebrand's factor antibody was used as an endothelial cell marker. The cytotoxic effect of immunoconjugates of anti-CD105 monoclonal antibody and dextran binding mitomycin C on human umbilical vein endothelial cells (HUVECs) was evaluated in vitro.

RESULTS

Endothelial cells demonstrated strong immunoreactivity of CD105 in all surgically excised CNV membranes. In the monkey eye, CD105-positive cells were detected only in CNV lesions but not in normal chorioretinal tissues. Immunoconjugates with anti-CD105 monoclonal antibody showed a specific inhibitory effect on proliferating HU-VECs.

CONCLUSIONS

These results suggest that anti-CD105 monoclonal antibody-mediated drug targeting has a potential to treat CNV in AMD.

Gastric amyloidosis with massive bleeding requiring emergency surgery

We report a 66-year-old woman who had massive bleeding from a gastric ulcer complicating primary systemic amyloidosis, in whom emergency surgery proved lifesaving. Physical examination revealed anemia and macroglossia. Gastroscopy was performed, and an extensive, irregular, hemorrhagic ulcer was found in the gastric body. Biopsy resulted in a diagnosis of amyloidosis. On the 11th hospital day the patient went into shock as a result of a massive hemorrhage. Emergency surgery was performed, but the extent of the submucosal lesion in the stomach could not be identified, and total gastrectomy was unavoidable. Histological examination of the surgical specimen and biopsy tissue collected from other organs revealed amyloid deposition extending from the submucosa to the muscularis propria of the stomach. There was also deposition of large amounts of amyloid around the small blood vessels in the liver and under the mucosa of the small intestine. The amyloid was AA-antibody-negative and resistant to treatment with K2MO4, and a diagnosis of AL-type systemic amyloidosis was made. The patient's general condition recovered after the operation, but on the 103rd hospital day, she experienced sudden onset of arrhythmia and died. Patients with amyloidosis in whom gastrointestinal surgery is performed are rare; only 41 cases, including our own, have been reported in the Japanese literature since 1972.

[Biological regulation of copper and selective removal of copper: therapy for Wilson disease and its molecular mechanism]

Copper (Cu) is an essential trace element and constitutes the active center of the redox Cu enzymes such as Cu, Zn-superoxide dismutase (Cu, Zn-SOD), ceruloplasmin and cytochrome c oxidase. Among hereditary diseases due to a defect in the metabolism of Cu, Menkes disease (caused by a Cu deficiency) and Wilson disease (caused by the excessive accumulation of Cu) have been shown to be caused by the mutation of genes encoding Cu-binding ATPase for the efflux of Cu, ATP7A and ATP7B, respectively. Following the identification of these causative genes, intracellular Cu transporters (Cu chaperones) specific for the Golgi apparatus, mitochondria and Cu, Zn-SOD were discovered, and these findings have facilitated the study of the underlying mechanisms of the biological regulation of Cu. Apart from these physiological and biochemical studies, toxicological studies have elucidated the underlying mechanisms of the occurrence of acute hepatitis caused by the accumulation of Cu accumulating in the liver of an animal model for Wilson disease, LEC rats. In these toxicological studies, two biological aspects of metallothionein (MT), i.e., antioxidant and prooxidant depending on the Cu/Zn ratio in Cu-containing MT have been proposed. The present article overviews the recent findings on the biological regulation of Cu and on the toxicological aspect of Cu. It is known that Cu forms a stable ternary complex with molybdenum and sulfur under reductive conditions in the body. On the basis of this observation, tetrathiomolybdate (TTM) has been applied to remove Cu from the liver of Long-Evans rats with a cinnamon-like coat color (LEC) rats. Precise mechanisms underlying the complex formation between Cu bound to MT and TTM were presented, and an appropriate protocol for the chelation therapy was also proposed together with the mechanisms underlying the occurrence of side-effects.

Ocular and systemic features of Peters' anomaly

BACKGROUND

To clarify the relationship between associated systemic anomalies and ocular manifestations in patients with Peters' anomaly, a retrospective study was conducted.

METHODS

We classified 37 patients with Peters' anomaly into two groups, one with (+) and one without (-) systemic anomalies.

RESULTS

The systemic anomaly (+) group consisted of 13 patients, eight males and five females, with mean age of 2.3 months. Peters' anomaly was bilateral in six cases and unilateral in seven. Corneolenticular adhesion was observed in 11 cases. Associated ocular anomalies were seen in 12 cases, and developmental glaucoma was present in eight cases. The systemic anomaly (-) group comprised 24 patients, 13 males and 11 females, with mean age of 28.3 months. Peters' anomaly was bilateral in 11 cases and unilateral in 13. Corneolenticular adhesion was observed in five cases. The associated ocular anomalies were observed in 10 cases, and developmental glaucoma was accompanied in six cases. The incidences of cases with corneolenticular adhesion, those with other ocular anomalies, and those with glaucoma were significantly higher in the systemic anomaly (+) group than in the systemic anomaly (-) group.

CONCLUSIONS

Peters' anomaly accompanying corneolenticular adhesion and/or other ocular anomalies should be evaluated for the presence of systemic anomalies.

Biodegradable scleral implant for controlled intraocular delivery of betamethasone phosphate

We evaluated nail-like, biodegradable scleral implants as a controlled intraocular delivery system of betamethasone phosphate (BP) for the treatment of chronic uveitis using pigmented rabbits. The scleral implants, which contained 10% and 25% of BP (weight 8.5 mg; length 5 mm), were made of poly (D,L-lactide-co-glycolide) (PLGA). In vivo release and retinal toxicity after implantation were also studied in pigmented rabbits. The in vitro release studies demonstrated the 10% and 25% BP-loaded scleral implants released BP in a biphasic release pattern for at least 1 month. The BP concentrations in the vitreous and the retina/choroid after application of scleral implants in pigmented rabbit eyes stayed within the concentration range capable of suppressing inflammatory responses for over 1 month. The BP concentration was greater in the retina/choroid than in the vitreous throughout the study. No substantial toxic reactions in the retina were observed by electroretinography. Our findings suggest that the BP-loaded scleral implant may be a promising device for treatment of chronic uveitis.

An induced proximity model for NF-kappa B activation in the Nod1/RICK and RIP signaling pathways

Nod1 is an Apaf-1-like molecule composed of a caspase-recruitment domain (CARD), nucleotide-binding domain, and leucine-rich repeats that associates with the CARD-containing kinase RICK and activates nuclear factor kappaB (NF-kappaB). We show that self-association of Nod1 mediates proximity of RICK and the interaction of RICK with the gamma subunit of the IkappaB kinase (IKKgamma). Similarly, the RICK-related kinase RIP associated via its intermediate region with IKKgamma. A mutant form of IKKgamma deficient in binding to IKKalpha and IKKbeta inhibited NF-kappaB activation induced by RICK or RIP. Enforced oligomerization of RICK or RIP as well as of IKKgamma, IKKalpha, or IKKbeta was sufficient for induction of NF-kappaB activation. Thus, the proximity of RICK, RIP, and IKK complexes may play an important role for NF-kappaB activation during Nod1 oligomerization or trimerization of the tumor necrosis factor alpha receptor.

Long-term outcome after radiation therapy for subfoveal choroidal neovascularization associated with age-related macular degeneration

PURPOSE

The purpose of this study was to investigate the long-term effect of low-dose radiation therapy on subfoveal choroidal neovascularization associated with age-related macular degeneration.

METHODS

The clinical course and visual outcome were compared retrospectively among two treated groups and a control group; 15 patients (15 eyes) received 10 Gy, another 15 patients (15 eyes) received 20 Gy. The control group consisted of 15 patients (15 eyes) without treatment. All patients were followed up for at least 18 months, and most were followed up for 3 years. The macula was irradiated with either 10 Gy in 5 fractions or with 20 Gy in 10 fractions after computed tomography (CT) simulation enabled real-time treatment planning from multiple CT slices.

RESULTS

During the 3 years of follow-up, the lesions became better in 5 eyes, unchanged in 1, and worse in 9 with 10 Gy radiation; better in 7 eyes, unchanged in 1, and worse in 7 eyes with 20 Gy; and better in 1 eye and worse in 14 with no treatment. The difference between the groups treated with radiation and the control was statistically significant (P <.05). Visual acuity was also significantly better in the group receiving 20 Gy than in the control group up to 2 years after radiation (P <.01).

CONCLUSION

Radiation may extend the period of good visual function substantially by reducing subfoveal choroidal neovascularization activity.

Protective effects of selectin ligands/inhibitor (SKK-60060) against retinal ischemia-reperfusion injury

A newly developed selSep;71(3)28 to block P- and L-selectins in vitro. We examined its inhibition of leukocyte-endothelial interactions in vivo against retinal ischemia-reperfusion injury and protective effects on ischemia-induced retinal damage. Retinal ischemia was induced by temporary ligation of the optic sheath for 60 min in anesthetized pigmented rats. SKK-60060 was administered 5 min before reperfusion and 4, 12, 24 and 48 hr thereafter, and leukocyte dynamics in the retinal microcirculation were evaluated using acridine orange digital fluorography. After 7 days of reperfusion, ischemia-induced retinal damage was also assessed histologically.SKK-60060 treatment suppressed leukocyte rolling during the reperfusion period; their numbers in the SKK-60060-treated rats were reduced by 67.0% (P < 0. 01) and 53.2% (P < 0.01) at 12 and 24 hr, respectively. The subsequent leukocyte accumulation was also inhibited in SKK-60060-treated rats; accumulated leukocytes in the SKK-60060-treated rats were reduced by 72.8% (P < 0.01) and 53.4% (P < 0.01) at 12 and 24 hr, respectively. Retinal venous vasodilation in SKK-60060-treated rats were significantly suppressed at each time point (P < 0.05). Histological examination demonstrated protective effects of SKK-60060 on ischemia-induced retinal damage, which were more substantial in the inner retina (P < 0.01).SKK-60060 significantly inhibits the leukocyte rolling along the major retinal veins and their accumulation during the reperfusion period. These results suggest therapeutic potential of SKK-60060 for ischemia-reperfusion injury.

Leukocyte-endothelial cell interactions in diabetic retina after transient retinal ischemia

Diabetes is associated with increased neural damage after transient cerebral ischemia. Recently, leukocytes, which are thought to play a central role in ischemia-reperfusion injury, have been suggested to be involved in exacerbated damage after transient ischemia in diabetic animals. The present study was designed to clarify whether the anticipated worse outcome after transient cerebral ischemia in diabetic animals was due to augmented leukocyte-mediated neural injury. Using rats with streptozotocin-induced diabetes of 4-wk duration, we investigated leukocyte-endothelial cell interactions during reperfusion after a transient 60-min period of retinal ischemia. Unexpectedly, postischemic diabetic retina showed no active leukocyte-endothelial cell interactions during reperfusion. The maximal numbers of rolling and accumulating leukocytes in diabetic retina were reduced by 73.6 and 41.2%, respectively, compared with those in nondiabetic rats. In addition, neither preischemic insulin treatment of diabetic rats nor preischemic glucose infusion of nondiabetic rats significantly influenced leukocyte-endothelial cell interactions during reperfusion. The present study demonstrated that high blood glucose concentration before induction of ischemia did not exacerbate leukocyte involvement in the postischemic retinal injury. Furthermore, diabetic retina showed suppressed leukocyte-endothelial cells interactions after transient ischemia, perhaps due to an adaptive mechanism that developed during the period of induced diabetes.

Amplified gene location in chromosomal DNA affected recombinant protein production and stability of amplified genes

Previously, we established an easy and quick construction method for obtaining a stable and highly productive gene-amplified recombinant Chinese hamster ovary (CHO) cell line. With a gradual increase in methotrexate (MTX) concentration, gene-amplified cell pools had high and stable specific growth and production rates. Moreover, the phenotype of gene-amplified cells seemed to be affected by the location of the amplified gene in chromosomal DNA. We suspected that various kinds of gene-amplified cells might appear during the long-term selection to construct gene-amplified cell pools. To clarify the behavior of gene-amplified cell pools during a stepwise increase of MTX concentration, we isolated gene-amplified clones derived from gene-amplified cell pools. We compared the characteristics of isolated clones, such as the productivity of recombinant protein, stability of amplified genes, and the location of amplified genes. As a result, telomere-type clones, in which the amplified gene was located near the telomeric region, were found to be more stable and productive than other types of clones. Telomere-type clones had over 100 copies of amplified genes in the chromosomal DNA. In contrast, a large number of other types of clones had less than 10 copies of amplified genes. During long-term cultivation in the absence of MTX, in other types of clones, amplified genes rapidly decreased in the chromosomal DNA.

Central bisegmentectomy of the liver plus caudate lobectomy for carcinoma of the gallbladder

Central bisegmentectomy of the liver is recommended as a radical surgical procedure for patients with liver-bed gallbladder carcinoma, which tends to directly invade the hepatic parenchyma through the liver bed. In this article, we describe the indications and our surgical techniques for central bisegmentectomy of the liver plus caudate lobectomy for carcinoma of the gallbladder. We employ combined resection of the caudate lobe, because the caudate lobe often becomes involved even in patients with liver-bed carcinoma. Resection of the extrahepatic bile duct is also required to achieve complete lymphadenectomy within the hepatoduodenal ligament, because tumor invasion of the hepatoduodenal ligament is frequently found. Extensive lymphadenectomy around the head of the pancreas together with removal of the para-aortic lymph nodes should be performed in patients with extensive lymph node metastases.