Failure of stent-assisted endovascular treatment for ruptured dissecting aneurysms of the basilar artery

We report two instructive cases of ruptured dissecting aneurysm of the basilar artery. Although stent-assisted endovascular treatment was successful, recurrent bleeding occurred 4 h after the procedure in one patient, and the other's basilar artery occluded 6 days after the procedure. These cases suggest that the high porosity of currently available stents may be insufficient to induce intraluminal thrombosis and merely stenting may fail to prevent bleeding, while postoperative anticoagulation alone may be inadequate to prevent occlusion of the stented vessel.

Analytical description of a neutral-induced tripole vortex in a plasma

An analytical description of a stationary triple vortex, observed in a cylindrical plasma, is presented. The concentration of neutrals, which is rather high in the experiment, turns out to be of crucial importance due to a spatially dependent distribution. In the radial direction the neutral concentration is paraboliclike, yielding an effective radial force directed towards the axis of the system. This neutral force causes the rotation of the plasma in the direction which is opposite to the E-->xB--> drift. The stationary triple vortex develops for a starting Gaussian-density distribution and a rigid-body rotation of the plasma column.

Is NF-kappaB a useful therapeutic target in rheumatoid arthritis?

There is increasing evidence that NF-kappaB is a major, if not the major transcription factor regulating inflammation and immunity. While this implies that blocking NF-kappaB might be therapeutically beneficial, it raises clear questions regarding the balance between efficacy and safety. In this brief review we discuss the effects of NF-kappaB blockade in rheumatoid arthritis, inflammation and immunity, and consider possible therapeutic targets within the NF-kappaB family.

Methicillin-resistant Staphylococcus aureus endocarditis following repair of tetralogy of Fallot

Infectious endocarditis following cardiac surgery, particularly that caused by methicillin-resistant Staphylococcus, aureus is a rare and highly lethal complication. We report a case of a 2-year-old girl who developed methicillin-resistant S. aureus endocarditis and mediastinitis following the intracardiac repair of tetralogy of Fallot using Dacron patches. The patient enveloped severe bacteremia accompanied by disseminated intravascular coagulation and progressive enlargement of vegetation. Despite this condition, the patient was successfully treated by repair using double autogenous pericardial patches. Aggressive removal of foreign material and replacement with autogenous tissue resulted in a favorable outcome.

Development of a cryopreservation procedure employing a freezer bag for pancreatic islets using a newly developed cryoprotectant

One of the most important requirements for success in clinical islet transplantation is the use of a large number of viable donor islets. To achieve this, the ability to cryopreserve islets and to establish an islet bank are critical. Previously, we developed a two-step cryopreservation procedure with freezing tubes utilizing low and high concentrations of dimethyl sulfoxide (DMSO) and using a fully automated cryomachine for human pancreatic islets and porcine islet-like cell clusters (ICCs). Based on these experiments, we developed a simple and efficient cryopreservation procedure of a freezer bag for isolated islets using a fully automated computer-controlled cryomachine with a newly developed cryoprotectant consisting of ethylene glycol (EG) instead of DMSO for decreasing injury of the islets by freezing. A 250 ml Cryocyte blood freezer bag and our newly developed cryoprotectant containing ethylene glycol (EG) were used in the freezing procedure. The islets were frozen by a fully automated computer-controlled cryomachine (GE 9,000) with our original program of slow cooling. Nucleation occurred at -8 degrees C, and the frozen islets were stored at -196 degrees C in a liquid nitrogen tank. The frozen-stored islets were subsequently rapidly thawed in a 37 degrees C water bath and cultured before viability testing. In vitro function, the stimulation index of insulin release during the static incubation test for rat islets cryopreserved in a freezer bag vs. nonfrozen islets as control, was 2.13 +/- 0.42 and 2.02 +/- 0.38 (94.8% compared with control), respectively (n = 5, p = NS). The islet recovery compared with the nonfrozen control group was 85% (n = 5) in insulin content. When 1000 rat islets cryopreserved in a freezer bag were transplanted into the renal capsule of diabetic athymic mice, all the mice became normoglycemic within 7 days from transplantation. Before nephrectomy, the intravenous glucose torelance test (IVGTT) was performed. The fractional decay constant of the glucose level (K value) of the frozen-thawed group was 0.42 +/- 0.06%/min. A histological study of renal subcapsular grafts demonstrated the morphological integrity of the islets. These results demonstrate the utility of our cryopreservation procedure of a freezer bag for isolated islets using a fully automated computer-controlled cryomachine with a newly developed cryoprotectant for the maintenance of viability and function of frozen-stored islets both in culture and after transplantation. Cryopreservation using freezer bags with the new cryoprotectant is an effective and simple method for making an islet bank for clinical trials of islet transplantation.

Maternal and developmental toxicity in mice by aminophenylnorharman, formed from norharman and aniline

9-(4'-Aminophenyl)-9H-pyrido [3,4-b] indole (aminophenylnorharman, APNH) is a novel mutagenic heterocyclic amine, produced by the reaction of norharman with aniline in the presence of S9 mix. In the present study, the maternal and developmental toxicity of APNH were investigated in ICR mice administered oral doses of 0, 0.625, 1.25, 2.5 or 5 mg/kg/day on gestational days (GD) 6 through 15 or 0, 5, 10, or 20 mg/kg on GD 12. Maternal and foetal parameters were evaluated on day 18 of gestation. Foetuses of dams treated on GD 6-15 were examined for external and skeletal malformations and variations, and foetuses of dams treated on GD 12 were inspected for cleft palate. Maternal death occurred when APNH was administered at 5 mg/kg/day on GD 6-15. No significant decrease in body weight gain during the administration period was observed at doses of 2.5 mg/kg/day or less when applied on GD 6-15. Adverse changes in general condition of dams were observed in the groups treated at doses of 2.5 mg/kg/day and above on GD 6-15, whereas no adverse effects on dams were noted even when APNH was applied at a fairly high dose on GD 12. Intracytoplasmic vacuolation in hepatocytes, necrosis of proximal tubular epithelial cells and desquamation of necrotic epithelial cells in the tubular lumen were observed in dams treated with APNH at 2.5 or 5 mg/kg/day on GD 6-15. Increased preimplantation loss was observed at 5 mg/kg/day and post-implantation loss was observed at 2.5 mg/kg/day and above when applied on GD 6-15, or at 20 mg/kg when applied on GD 12. Foetal body weight was decreased by APNH in a dose-dependent manner. The frequency of external malformations (cleft palate) was significantly increased in the group treated with APNH at 2.5 mg/kg/ day on GD 6-15 compared to the controls. However, there were no foetuses with cleft palate even when APNH was given at 20 mg/kg on GD 12. No significant increases in skeletally malformed foetuses were found in any APNH-treated group. The frequency of lumbar ribs was increased dose dependently. This study demonstrated the developmental toxicity of a mutagenic compound, APNH, in mice at maternally toxic doses, and that cleft palate observed in term foetuses resulted from the adverse effect of APNH on the maternal environment during organogenesis. More detailed studies are warranted to assess the possible risks to pregnant women from exposure to APNH.

Exogenous expression of Pit-1 in AtT-20 corticotropic cells induces endogenous growth hormone gene transcription

The pituitary-specific POU-homeodomain transcription factor, Pit-1, is known to regulate the expression of the GH gene in somatotropes, prolactin (PRL) in lactotropes, and TSH in thyrotropes. It is not normally expressed in corticotropes or gonadotropes. We addressed the question of whether exogenous Pit-1 was sufficient to induce ectopic transcription of the GH gene in the corticotropic cell line, AtT-20, or the gonadotropic cell line, alpha T3-1. A fusion gene composed of enhanced green fluorescent protein gene and human Pit-1 cDNA was transfected into AtT-20 and alpha T3-1 cells. The endogenous mouse GH mRNA was induced in three of nine AtT-20 cell lines and one of three alpha T3-1 cell lines containing the fusion gene. A small amount of GH protein was also detected in these cell lines. These data indicate that transfected Pit-1 is capable of inducing transcription of the GH gene in AtT-20 cells and alpha T3-1 cells. These data also suggest that synergistic co-factors might be required to transcribe the GH gene effectively for translation into GH protein. Furthermore, our findings support the hypothesis that the function of anterior pituitary cells is determined by the combinatorial action of specific transcription factors.

Effects of endocrine disrupting chemicals on the microtubule network in Chinese hamster V79 cells in culture and in Sertoli cells in rats

The effects of ten endocrine disrupting chemicals, i.e., bisphenol A (BPA), p-nonylphenol (NP), p-octylphenol (OP), p-pentylphenol (PP), butyl benzyl phthalate (BBP), dicyclohexyl phthalate (DCHP), di-n-butyl phthalate (DBP), tetrabutyltin (TBT), tri-n-butyltin chloride (TBC), and di-n-butyltin dichloride (DBD), as well as 17 beta-estradiol (E(2)) as a positive control on the microtubule network in Chinese hamster V79 cells in culture were examined by the indirect immunofluorescence method using anti-beta-tubulin antibody. In the whole-animal system, the effects of BPA, NP, OP, BBP, DBD, and E(2) as well as vinblastine sulfate (VB) as a positive control on microtubules in the cytoplasm of Sertoli cells in rats were examined by electron microscopy. In Chinese hamster V79 cells, TBC and DBD showed higher microtubule-disruptive activity than E(2), while other chemicals had less activity than E(2). The ranking for efficiency on microtubule disruption was (TBC falling dots DBD) > (E(2) = TBT) > (BPA = alkylphenols, NP and OP) >> (phthalate esters, BBP, DHP, and DBP). In rats as a whole-animal system, no disrupting effects on the microtubule network in the cytoplasm of Sertoli cells were observed under any environmental chemicals tested, whereas exposure to VB resulted in marked disruption of the microtubule network. The results of this study suggested that some endocrine disrupting chemicals have disrupting effects on the microtubule network in vitro, but no such effects in vivo.

[Emergent surgical treatment of type A acute aortic dissection in an elderly patient]

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Plasma phosphatidylcholine hydroperoxide-reducing activity in pregnant women

Plasma glutathione peroxidase (PGPx) and apolipoproteins A-I, A-II, and B-100 reduce phosphatidylcholine hydroperoxide (PC-OOH) to its hydroxide (PC-OH). To elucidate the relative importance of the reduction pathways we developed a simple assay for measuring total PC-OOH-reducing activity. Human plasma was incubated with 1-palmitoyl-2-linoleoyl-phosphatidylcholine hydroperoxide and the time-dependent reduction was confirmed by its hydroxide formation, measured by reversed-phase high performance liquid chromatography. We determined the PC-OOH reducing activity in blood plasma of healthy men and women as 119 +/- 7 (n = 13, aged 27 to 45) and 101 +/- 4 microM/h (n = 5, aged 24 to 30), respectively. In addition, we also measured PC-OOH-reducing activity in the plasma of 53 pregnant women since they usually show hyperlipidemia or hyper-apolipoproteinemia. The average rate of PC-OOH reduction was 101 +/- 34 microM/hr. The PC-OOH-reducing activity was not affected by the addition of iodoacetamide, an inhibitor of PGPx, suggesting that the activity is due to apolipoproteins. A significant correlation between plasma reducing activity with apolipoprotein B-100 was observed (r = 0.290), but not with apolipoprotein A-I (r = 0.118). In pre-eclamptic patients, about an 8% decrease in plasma PC-OOH-reducing activity was observed as compared to the normal pregnancy group, although the decrease was not statistically significant.

A defect in the cytochrome b large subunit in complex II causes both superoxide anion overproduction and abnormal energy metabolism in Caenorhabditis elegans

A mev-1(kn1) mutant of the nematode Caenorhabditis elegans is defective in the cytochrome b large subunit (Cyt-1/ceSDHC) in complex II of the mitochondrial electron transport chain. We have previously shown that a mutation in mev-1 causes shortened life span and rapid accumulation of aging markers such as fluorescent materials and protein carbonyls in an oxygen-dependent fashion. However, it remains unclear as to whether this hypersensitivity is caused by direct toxicity of the exogenous oxygen or by the damage of endogenous reactive oxygen species derived from mitochondria. Here we report important biochemical changes in mev-1 animals that serve to explain their abnormalities under normoxic conditions: (i) an overproduction of superoxide anion from mitochondria; and (ii) a reciprocal reduction in glutathione content even under atmospheric oxygen. In addition, unlike wild type, the levels of superoxide anion production from mev-1 mitochondria were significantly elevated under hyperoxia. Under normal circumstances, it is well known that superoxide anion is produced at complexes I and III in the electron transport system. Our data suggest that the mev-1(kn1) mutation increases superoxide anion production at complex II itself rather than at complexes I and III. The mev-1 mutant also had a lactate level 2-fold higher than wild type, indicative of lactic acidosis, a hallmark of human mitochondrial diseases. These data indicate that Cyt-1/ceSDHC plays an important role not only in energy metabolism but also in superoxide anion production that is critically involved in sensitivity to atmospheric oxygen.

High efficiency gene transfer is an efficient way of defining therapeutic targets: a functional genomics approach

BACKGROUND

Dendritic cells are the most potent antigen presenting cells and key to many aspects of the immune function. Studying the intracellular signalling mechanism used by dendritic cells would provide an insight into the functioning of these cells and give clues to strategies for immunomodulation.

METHOD

Highly efficient adenoviral infection of dendritic cells for the delivery of transgenes was obtained. These viral vectors were used to introduce IkappaB alpha into dendritic cells for the inhibition of NF-kappaB. This was used to investigate the role of NF-kappaB in dendritic cell function.

RESULTS

By blocking the NF-kappaB function a potent inhibition of the expression of costimulating molecules by dendritic cells with the concomitant loss of T cell stimulating function was demonstrated.

CONCLUSION

The use of adenoviral vectors may be a useful way of studying the role of genes in dendritic cell function.

Inhibition of intimal hyperplasia after balloon injury in rat carotid artery model using cis-element 'decoy' of nuclear factor-kappaB binding site as a novel molecular strategy

The transcription factor, NFkB, plays a pivotal role in the coordinated transactivation of cytokine and adhesion molecule genes involved in atherosclerosis and lesion formation after vascular injury. We hypothesized that synthetic double-stranded DNA with high affinity for NFkB may be introduced as a 'decoy' cis element to bind the transcription factor, and block gene activation, resulting in an effective therapeutic agent for treating intimal hyperplasia. In vivo transfection of NFkB decoy oligodeoxynucleotides (ODN) into balloon-injured rat carotid artery resulted in the inhibition of neointimal formation at 14 days after injury as compared with vessels transfected with scrambled ODN (P < 0.01). It is of importance to note that in the vessels transfected with NFkB decoy ODN, the expression of p53, a pro-apoptotic gene, was upregulated in neointimal area, followed by increased apoptosis at 14 days. In addition, gene expression of ICAM-1 and VCAM-1 was markedly decreased in blood vessels transfected with NFkB decoy ODN compared with scrambled ODN, whereas balloon injury induced ICAM and VCAM expression in the neointimal area. More importantly, the migration of macrophages and T-lymphocytes into the neointima and media was significantly inhibited by NFkB decoy ODN as compared with scrambled ODN. Here, we demonstrated that in vivo transfer of NFkB decoy ODN successfully inhibited neointimal formation after balloon injury, accompanied by (1) induction of apoptosis through p53 upregulation, and (2) inhibition of local inflammatory actions through the downregulation of adhesion molecules. These results suggest that decoy treatment against NFkB provides a new therapeutic strategy to inhibit neointimal hyperplasia after angioplasty.

Low-dose erythromycin reduces delayed gastric emptying and improves gastric motility after Billroth I pylorus-preserving pancreaticoduodenectomy

OBJECTIVE

To test the hypothesis that early and low doses of erythromycin reduce the incidence of early delayed gastric emptying (DGE) and induce phase 3 of the migratory motor complex in the stomach after Billroth I pylorus-preserving pancreaticoduodenectomy (PPPD).

SUMMARY BACKGROUND DATA

Delayed gastric emptying is a leading cause of complications after PPPD, occurring in up to 50% of patients. High doses of erythromycin (200 mg) accelerate gastric emptying after pancreaticoduodenectomy and reduce the incidence of DGE, although they induce strong contractions that do not migrate to the duodenum.

METHODS

Thirty-one patients were randomly assigned to either the erythromycin or control groups. The patients received erythromycin lactobionate (1 mg/kg) every 8 hours, or H2-receptor antagonists and gastrokinetic drugs from days 1 to 14 after surgery. On postoperative day 30, gastroduodenal motility was recorded in 14 patients.

RESULTS

Preoperative, intraoperative, and postoperative factors were comparable in the erythromycin and control groups. The erythromycin group had a shorter duration of nasogastric drainage, earlier resumption of eating, and a 75% reduction in the incidence of DGE. Erythromycin was an independent influence on nasogastric tube removal, and preservation of the right gastric vessels was a significant covariate. Low doses of erythromycin induced phase 3 of the migratory motor complex and phase 3-like activity, with the same characteristics as spontaneous phase 3, in 86% of patients: two had quiescent stomachs and the others had spontaneous phase 3 or phase 3-like activity.

CONCLUSIONS

Low doses of erythromycin reduced the incidence of DGE by 75% and induced phase 3 of the migratory motor complex after Billroth I PPPD. Low doses of erythromycin are preferable to high doses in the unfed period after PPPD.

Reproductive effects in male and female rats from neonatal exposure to p-octylphenol

A number of alkylphenolic compounds are used in a variety of commercial products and have been shown in in vitro studies to be weakly estrogenic, but in vivo data are not available addressing this issue in mammals. Human exposure to alkylphenols may occur not only from these environmental contaminants but also through contact with manufactured and metabolic breakdown products. In this study, Sprague-Dawley rats were exposed to octylphenol by oral gavage at doses of 0 (vehicle: corn oil), 12.5, 25, 50, or 100 mg/kg once daily on postnatal days 1 through 5 to examine its effects on male and female reproductive function after puberty. In addition, preputial separation and vaginal opening as endpoints of sexual maturation, estrous cycling, sperm count, serum testosterone concentration, and histopathologic changes of the reproductive organs of male and female rats were examined. Male reproductive organs were weighed at necropsy. Body weights of male and female rats exposed to octylphenol at 50 and 100 mg/kg throughout the study after the administration period, those of both sexes at 7 and 9 weeks of age in the 25 mg/kg group, and that of females at 9 weeks of age in the 12.5 mg/kg group were lower than those of controls. Significant delays in acquisition of puberty in males and females exposed to octylphenol at 50 and 100 mg/kg were observed. Estrous cycle, copulation and fertility, sperm count, and serum testosterone concentration were not affected by neonatal exposure to octylphenol. Significant decrease in absolute and relative prostate weight in the 12.5, 25, 50, and 100 mg/kg groups, and absolute epididymal weight in the 100 mg/kg group, increase in relative testes weight in the 100 mg/kg group, and relative seminal vesicle weights in the 50 and 100 mg/kg groups were found. Histopathologic analyses of reproductive organs in male and female rats exposed neonatally to octylphenol revealed no marked alterations. The results of this study indicate that early neonatal exposure to octylphenol by oral gavage did not cause dysfunction of reproductive performance (mating and fertility) in male or female rats, and no disruption of development of the reproductive tract was observed in male or female rats, while significant decreases in body weights in the 25 mg/kg and more groups, delays of sexual maturation in the 50 mg/kg and greater groups, and decrease in ventral prostate weights in all octylphenol-treated groups were found. Therefore, it is concluded that NOAEL (no-observed adverse effect level) for systemic toxicity was < or =12.5 mg/kg/day and that for reproductive toxicity was 100 mg/kg/day under the present experimental condition.

Pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation

Right atrial isomerism is well known to be associated with anomalous pulmonary venous drainage and a potentially dangerous sequel to pulmonary venous obstruction, and is associated with high mortality. We report a 16-month-old girl with pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation. Two years after surgery, she is doing well with 80% oxygen saturation and no further episodes of hemoptysis.

NMR structure of the hRap1 Myb motif reveals a canonical three-helix bundle lacking the positive surface charge typical of Myb DNA-binding domains

Mammalian telomeres are composed of long tandem arrays of double-stranded telomeric TTAGGG repeats associated with the telomeric DNA-binding proteins, TRF1 and TRF2. TRF1 and TRF2 contain a similar C-terminal Myb domain that mediates sequence-specific binding to telomeric DNA. In the budding yeast, telomeric DNA is associated with scRap1p, which has a central DNA-binding domain that contains two structurally related Myb domains connected by a long linker, an N-terminal BRCT domain, and a C-terminal RCT domain. Recently, the human ortholog of scRap1p (hRap1) was identified and shown to contain a BRCT domain and an RCT domain similar to scRap1p. However, hRap1 contained only one recognizable Myb motif in the center of the protein. Furthermore, while scRap1p binds telomeric DNA directly, hRap1 has no DNA-binding ability. Instead, hRap1 is tethered to telomeres by TRF2. Here, we have determined the solution structure of the Myb domain of hRap1 by NMR. It contains three helices maintained by a hydrophobic core. The architecture of the hRap1 Myb domain is very close to that of each of the Myb domains from TRF1, scRap1p and c-Myb. However, the electrostatic potential surface of the hRap1 Myb domain is distinguished from that of the other Myb domains. Each of the minimal DNA-binding domains, containing one Myb domain in TRF1 and two Myb domains in scRap1p and c-Myb, exhibits a positively charged broad surface that contacts closely the negatively charged backbone of DNA. By contrast, the hRap1 Myb domain shows no distinct positive surface, explaining its lack of DNA-binding activity. The hRap1 Myb domain may be a member of a second class of Myb motifs that lacks DNA-binding activity but may interact instead with other proteins. Other possible members of this class are the c-Myb R1 Myb domain and the Myb domains of ADA2 and Adf1. Thus, while the folds of all Myb domains resemble each other closely, the function of each Myb domain depends on the amino acid residues that are located on the surface of each protein.

Gene therapy for preventing neuronal death using hepatocyte growth factor: in vivo gene transfer of HGF to subarachnoid space prevents delayed neuronal death in gerbil hippocampal CA1 neurons

To develop a novel strategy to prevent delayed neuronal death (DND) following transient occlusion of arteries, the gene of hepatocyte growth factor (HGF), a novel neurotrophic factor, was transfected into the subarachnoid space of gerbils after transient forebrain ischemia. Importantly, transfection of HGF gene into the subarachnoid space prevented DND, accompanied by a significant increase in HGF in the cerebrospinal fluid. Prevention of DND by HGF is due to the inhibition of apoptosis through the blockade of bax translocation from the cytoplasm to the nucleus. HGF gene transfer into the subarachnoid space may provide a new therapeutic strategy for cerebrovascular disease.

Oral administration of clomiphene to neonatal rats causes reproductive tract abnormalities

Oral administration of clomiphene at 2, 4, or 8 mg/kg to 4-day-old rats caused multiple histopathological abnormalities of the reproductive tract in both male and female animals. No histopathological abnormalities were observed in 30-day-old male rats at any dose examined. In contrast, 30-day-old females showed hypertrophy of the myometrium at all doses examined, and hypertrophy of the luminal or glandular epithelium, and dilatation of the uterine lumen were observed in the highest dose group. In post-pubertal rats, histopathologically marked changes were observed in the testes and epididymides in males, and in the ovaries and uterus in females in the highest dose group. In addition, relative weight of male reproductive organs in the highest dose group was decreased as compared with that in the controls. These results suggested that early neonatal exposure to clomiphene induced marked reproductive tract abnormalities in males after puberty, as well as in females.

Crucial role of calpain in hypoxic PC12 cell death: calpain, but not caspases, mediates degradation of cytoskeletal proteins and protein kinase C-alpha and -delta

Ca2+ influx is one of the main causative events in hypoxic PC12 cell death, because an extracellular Ca2+ chelator, ethylene glycol bis (2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) inhibited and Ca2+ ionophore A23187 mimicked the hypoxic cell death. The hypoxic cell death was markedly prevented by a broad spectrum caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-FMK) as well as a calpain inhibitor, calpeptin, as assessed by nuclear staining with Hoechst 33258 and lactate dehydrogenase release. The processing of procaspase-3 was inhibited by z-VAD-FMK, but not by calpeptin. In contrast, z-VAD-FMK failed to block the proteolytic cleavage of fodrin-alpha, a preferential substrate for calpain. On the other hand, degradation of actin and fodrin-alpha was prevented by calpeptin but not by z-VAD-FMK. In addition, not only protein kinase C (PKC)-alpha but also PKC-delta were cleaved to generate approximately 46 kDa fragments. The PKC fragmentation was inhibited by calpeptin but not by z-VAD-FMK. These findings suggest that the extracellular Ca2+ influx induced by hypoxic stress activates calpain, resulting in the degradation of cytoskeletal proteins and generation of PKC fragments almost independently of caspase activation. Therefore, calpain may play an important role in hypoxic PC12 cell death.

Reproductive effects in male and female rats of neonatal exposure to genistein

Sprague-Dawley rats were administered genistein orally at doses of 12.5, 25, 50, or 100 mg/kg on postnatal days 1 through 5 to examine its effects on reproductive function after puberty. In addition, preputial separation and vaginal opening as endpoints of sexual maturation, estrous cycling, sperm count, serum testosterone concentration, and histopathologic changes of reproductive organs of male and female rats were examined. Body weights of male and female rats exposed to genistein at any dose level examined were lower than those of controls. Timing of preputial separation in males and timing of vaginal opening were not affected by genistein treatment. The number of females showing estrous cycle irregularities was increased by genistein treatment. The fertility of female rats exposed neonatally to genistein at 100 mg/kg was disrupted, while neonatal exposure to genistein did not affect male fertility. Neither sperm counts nor serum testosterone concentration were changed by neonatal exposure to genistein. Female rats exposed neonatally to genistein at 100 mg/kg showed histopathologic changes in the ovaries and uterus, while male rats showed no histopathologic alterations in the gonads. The results of this study indicate that early neonatal exposure to genistein caused dysfunction of postpubertal reproductive performance as well as abnormal development of gonads in female but not in male rats.

FR901469, a novel antifungal antibiotic from an unidentified fungus No. 11243. III. Structure determination

A novel antifungal antibiotic, FR901469, was isolated from an unidentified fungus No. 11243. It is a water-soluble 40-membered macrocyclic lipopeptidolactone, consisting of D-Ala, L-Tyr, L-Val, trans-4OH-L-Pro, trans-3OH-L-Pro, threo-3OH-L-Gln, Gly, L-Orn, L-Thr, three residues of D-alloThr and a (3R)-hydroxypalmitic acid. Its structure, including absolute configurations, was unequivocally determined as 1 based on chemical and spectroscopic evidence.

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta

OBJECTIVES

We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta.

METHODS

Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting.

RESULTS

Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors.

CONCLUSIONS

Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Role of NFkappaB in antigen presentation and development of regulatory T cells elucidated by treatment of dendritic cells with the proteasome inhibitor PSI

Dendritic cells (DC) are the most potent antigen-presenting cells for naive T cells, due to their high expression of MHC and costimulatory molecules, but relatively little is known about the biochemical pathways that regulate this function. We used the proteasome inhibitor N-benzyloxycarbonyl-Ile-Glu(O-tert-butyl)-Ala-leucinal (PSI) to demonstrate that DC antigen presentation is NFkappaB dependent. As PSI is not a specific inhibitor of NFkappaB, we reproduced this finding using a very specific approach, namely adenoviral gene transfer of IkappaBalpha, the naturally occurring inhibitor of NFkappaB. The mechanism for this inhibition of DC antigen presentation involves at least three aspects of antigen presenting function: down-regulation of HLA class II, down-regulation of CD86, and inhibition of the immunostimulatory cytokines IL-12 and TNF-alpha. In the light of the marked down-regulation of antigen-presentation cell function, it was of interest to investigate what effects exposure to PSI-treated DC might have on T cell function. It was found that immunological tolerance was induced, as challenge of T cells previously exposed to PSI-treated DC, with normal DC from the same donor did not restore their response, despite the presence of viable T cells. There were also changes in T cell surface markers, with down-regulation of CD3 and CD25 expression, and inhibition of the production of Th1 cytokines like IL-2 and IFN-gamma. These results demonstrates that NFkappaB is an effective target for blocking DC antigen presentation and inhibiting T cell-dependent immune responses, and this has implications for the development of therapeutic agents for use in multiple conditions, including transplantation, allergy and autoimmune diseases.

Results and problems in percutaneous transluminal angioplasty for internal carotid artery stenosis

SUMMARY

Percutaneous transluminal angioplasty (PTA) is currently performed as a therapeutic strategy for the management of the cervical carotid artery stenosis. In our clinic, PTA was performed successfully in all 24 patients initially. Restenosis was observed in 4 of 24 patients who received 3 to 6 month follow-up angiography. Repeated PTA was performed in 4 patients, 3 of whom were successfully treated, while severe wall dissection occurred in 1 patient. Furthermore, asymptomatic rerestenosis was noted in 1 of 4 patients who received repeated PTA. Dissection was noted in 5 of 28 procedures, which occurred more often in the patients with calcified or restenotic lesions. These results suggest that stenting or emergent surgery should be prepared in PTA of the carotid artery stenosis to avoid major complications, especially when the patients have calcified or restenotic lesions.