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.

The principle of digital subtraction angiography and radiological protection

SUMMARY

Recent improvements in x-ray technology have greatly contributed to the advancement of diagnostic imaging. Fluoroscopically guided neurointerventional procedures with digital subtraction angiography (DSA) are being performed with increasing frequency as the treatment of choice for a variety of neurovascular diseases. Radiation-induced skin injuries can occur after extended fluoroscopic exposure times, and the injuries have recently been reported. In this article, measured radiation doses at the surface of Rando Phantom with Skin Dose Monitor, and estimated and measured entrance skin doses in patients underwent neurointerventional procedures are reported as well as means of reducing radiation doses absorbed by patients and personnel to avoid occurrence of radiation-induced injuries.

Endovascular Treatment of Ruptured Intracranial Aneurysms using Platinum Coils in Patients over 70 Years of Age

SUMMARY

Endovascular treatment of intracranial aneurysms using platinum coils was performed in 26 patien with age over 70 years. The patients ranged from 70 to 86 years old (mean 77.5). Preoperative World Federation of Neurological Surgeons (WFNS) scale revealed that 6 patients were in grade I, 5 in grade II, 2 in grade III, 12 in grade IV, and 1 in grade V. The location of aneurysms are as follows; 10 were in the internal carotid artery, 7 in the anterior cerebral artery, 1 in the middle cerebral artery, and 8 in the vertebro- basilar system. Intra-aneurysmal occlusion was accomplished in 25 patients, resulting in 6 complete occlusion (24%), 3 neck remnant (12%), 11 body filling (44%), and both of neck remnant and body filling in 5 (20%). In one patient with vertebral artery union aneurysm, the parent artery was occluded just proximal to the aneurysm. Eleven of 13 patients with good clinical grade (grade I, II, and III) resulted in good clinical outcome, whereas 11 of 13 patients with poor clinical grade (grade IV and V) showed poor outcome. Periprocedural complications such as thromboembolism and intra-procedural rupture occurred in 5 patients (19.2%). Each of the complications was attributed to severe atherosclerotic changes of parent arteries. Symptomatic cerebral vasospasm occurred in only one patient (3.8%). In conclusion, endovascular coil emboilization is a useful therapeutic alternative for treating ruptured intracranial aneurysms in patients over 70 years of age, especially in patients with good clinical grade (better than grade III).

FGF-2 regulation of neurogenesis in adult hippocampus after brain injury

Fibroblast growth factor-2 (FGF-2) promotes proliferation of neuroprogenitor cells in culture and is up-regulated within brain after injury. Using mice genetically deficient in FGF-2 (FGF-2(-/-) mice), we addressed the importance of endogenously generated FGF-2 on neurogenesis within the hippocampus, a structure involved in spatial, declarative, and contextual memory, after seizures or ischemic injury. BrdUrd incorporation was used to mark dividing neuroprogenitor cells and NeuN expression to monitor their differentiation into neurons. In the wild-type strain, hippocampal FGF-2 increased after either kainic acid injection or middle cerebral artery occlusion, and the numbers of BrdUrd/NeuN-positive cells significantly increased on days 9 and 16 as compared with the controls. In FGF-2(-/-) mice, BrdUrd labeling was attenuated after kainic acid or middle cerebral artery occlusion, as was the number of neural cells colabeled with both BrdUrd and NeuN. After FGF-2(-/-) mice were injected intraventricularly with a herpes simplex virus-1 amplicon vector carrying FGF-2 gene, the number of BrdUrd-labeled cells increased significantly to values equivalent to wild-type littermates after kainate seizures. These results indicate that endogenously synthesized FGF-2 is necessary and sufficient to stimulate proliferation and differentiation of neuroprogenitor cells in the adult hippocampus after brain insult.

Molecular cloning and characterization of a gene expressed in mouse developing tongue, mDscr5 gene, a homolog of human DSCR5 (Down syndrome Critical Region gene 5)

For understanding the pathogenesis of Down syndrome (DS), it is important to identify and characterize the genes on Chromosome (Chr) 21, especially those in the Down syndrome critical region (DSCR) on Chr 21q22.2. Recently we have determined 33.5 Mb (more than 99%) of DNA sequence of Chr 21 and, from these sequence data, we identified a novel gene, DSCR5 (transcript = 0.8 kb), from DSCR by combination of computational gene prediction and cDNA screening. For functional analysis of DSCR5, we identified a mouse homolog of the DSCR5 cDNA, and termed it mDscr5 (transcript length = 0.8 kb). The gene was mapped to mouse Chr 16 C3-C4, the syntenic region of human Chr 21, and encodes an amino acid of 132 residues with 90% identity to DSCR5. In situ hybridization showed that mDscr5 is predominantly expressed in the developing tongue. To our best knowledge, no other gene in DSCR is reported to be expressed in tongue, so that DSCR5 may be the first candidate to elucidate the pathophysiology of tongue malformation observed in DS.

Reproductive effects of nonylphenol in rats after gavage administration: a two-generation study

The potential reproductive toxicity of nonylphenol (NP) was assessed in a two-generation reproductive toxicity study. Groups of 25 male and female Crj:CD (SD) IGS rats were given NP by gavage at levels of 2, 10, or 50 mg/kg, and 25 males and females were given corn oil as controls. No adverse changes in clinical signs were observed in any rats throughout the study. Significant increases in the liver, kidney and pituitary gland weights in males, and decreases in thymus weight in males and in ovary weight in females were observed in the 50 mg/kg group. NP did not affect sperm characteristics or the estrous cycle at any dose administered. A significant increase in the TSH level was observed in males in the 50 mg/kg group. No adverse effects of NP on reproduction were found. At necropsy, no treatment-related alterations were observed in any organs including the reproductive tissues in any group. Histopathologic changes were found in the liver of male and female rats and kidneys of males in the 50 mg/kg group. The viability of offspring from postnatal day 0 to 4 in the 50 mg/kg group was reduced as compared with that in the controls, although growth was not affected by NP administration. On postnatal day 22, an increase in the serum FSH level and decrease in T(3) level for males, and decreases in LH and TSH levels and an increase in T(3) levels for females were observed in the 50 mg/kg group. NP did not affect the timing of preputial separation, while vaginal opening was accelerated in the 50 mg/kg group. No adverse changes were found in behavior or learning in the offspring of NP-treated groups. There were no treatment-related changes in any reproductive parameter, including estrous cycle, mating, fertility, delivery, and lactation, except for significant decreases in the numbers of implantation sites and live pups, and a significant decrease in ovary weight in the 50 mg/kg group. Kidney and liver weight were increased in males in the 50 mg/kg group. Histopathologic examination revealed changes in the liver of males and females of the 50 mg/kg group. No treatment-related changes were observed in the sperm characteristics. Hormone data should be interpreted cautiously until the findings are repeated and confirmed by further studies. These results of NP suggested that the no observed adverse effect level (NOAEL) on reproductive capacity is 50 mg/kg/day or greater in parent animals, and 10 mg/kg/day in the next generation under the present experimental condition.

Effective antigen presentation by dendritic cells is NF-kappaB dependent: coordinate regulation of MHC, co-stimulatory molecules and cytokines

Antigen presentation is a key rate-limiting step in the immune response. Dendritic cells (DC) are the most potent antigen-presenting cells for naive T cells, due to their high expression of MHC and co-stimulatory molecules, but little is known about the biochemical pathways that regulate this function. We here demonstrate that monocyte-derived mature DC can be infected with adenovirus at high efficiency (>95%) and that this procedure can be used to dissect out which pathways are essential for inducing DC antigen presentation to naive T cells. Using adenoviral transfer of the endogenous inhibitor of NF-kappaB, IkappaBalpha, we show that DC antigen presentation is NF-kappaB dependent. The mechanism for this is that NF-kappaB is essential for three aspects of antigen-presenting function: blocking NF-kappaB coordinately down-regulates HLA class II, co-stimulatory molecules like CD80, CD86 and CD40, and immuno-stimulatory cytokines like IL-12 and tumor necrosis factor-alpha. In contrast adhesion molecules are up-regulated after infection with the adenovirus transferring IkappaBalpha, indicating that NF-kappaB also regulates the duration of T cell-DC interaction. These results establish NF-kappaB as an effective target for blocking DC antigen presentation and inhibiting T cell-dependent immune responses, and this finding has potential implications for the development of therapeutic agents for use in allergy, autoimmunity and transplantation.

Genetic transformation system for a psychrotrophic deep-sea bacterium: isolation and characterization of a psychrotrophic plasmid

A versatile system that permits genetic manipulation of a psychrotrophic deep-sea bacterium, Pseudoalteromonas sp. PS1M3, has been developed. A cryptic indigenous plasmid, pPS1M3, of 3.1 kb from the above strain was isolated and characterized. The nucleotide sequence analysis of plasmid pPS1M3 revealed the presence of one open reading frame, and its deduced amino acid sequence was identified as the essential protein for plasmid maintenance. Transformation with the pPS1M3 harboring antibiotic resistance genes by electroporation was fully successful using the pPS1M3-cured strain as a host. This plasmid was quite stable under nonselective culture conditions for about 100 generations at 4 degrees C. The copy number of this plasmid in the cell was about 5 copies per chromosome.

Role of ceramide during cisplatin-induced apoptosis in C6 glioma cells

Cisplatin is commonly used for the treatment of malignant brain tumors. However, the mechanisms of cell death by cisplatin are not fully understood. Therefore, the present study was designed to elucidate the apoptotic signaling pathway(s) activated by cisplatin in a C6 rat glioma cell line. C6 cells were treated with various concentrations of cisplatin (0.2-10 microg/ml) for 24-72 h. At 10 microg/ml cisplatin, over 90% of the cells became dead at 72 h. Apoptotic death was confirmed by condensation and fragmentation of nuclei, and DNA laddering. Even in cells treated with 1.5 microg/ml cisplatin, typical apoptotic cells were observed at 72 h. The intracellular level of ceramide, measured Escherichia coli diacylglycerol kinase markedly increased during 24-72 h after the addition of 10 microg/ml cisplatin. The activity of caspase-3(-like) proteases increased and reached a peak at 48 h. Inhibitors of caspases reduced the number of apoptotic cells. Pretreatment of C6 cells with glutathione or N-acetyl-cysteine, which are known to block the activation of neutral magnesium-dependent sphingomyelinase, inhibited ceramide formation, leading to suppression of both activation of caspase-3(-like) proteases and apoptosis by cisplatin. In contrast, pretreatment of the cells with N-oleoylethanolamine (OE), a ceramidase inhibitor, potentiated apoptosis induced by cisplatin. Furthermore, OE enhanced sensitivity of the cisplatin-resistant cells to cisplatin. These results suggest that ceramide is closely implicated in apoptosis of glioma cells by cisplatin through activation of caspase-3(-like) proteases.

Serum p53 antibody as a useful marker for monitoring of treatment of superficial colorectal adenocarcinoma after endoscopic resection

BACKGROUND

Mutation of the p53 gene is a genetic alteration found in human cancers. Overexpression of p53 has been found to induce antibody production in serum, and, recently, the simple detection of serum antibody has been made possible. The aim of this study was to evaluate the potential role of serum p53 antibody in the early diagnosis of superficial colorectal cancer and in the monitoring of its treatment after endoscopic resection.

METHODS

In a prospective study, our subjects were 27 patients with superficial colorectal adenocarcinomas, whose results were compared with those in 38 patients with benign adenomas; all patients were treated by endoscopic resection. The correlation between serum p53 antibody levels before and within 3 weeks after resection was determined, using an immunoassay. Immunohistological staining for p53 was also performed, and its sensitivity was compared with that of two other tumor markers.

RESULTS

Preoperatively, serum p53 antibody was detected in 63.0% (17/27) patients with adenocarcinoma and in 2.6% (1/38) patients with adenoma, showing a significant difference (P < 0.001). However, the two other markers carcinoembryonic antigen (CEA) and carbohydrate antigen CA19-9, showed no significant difference between superficial colorectal adenocarcinoma and adenoma. The serum p53 antibody status was strongly correlated with p53 immunostaining in adenocarcinoma (P = 0.0065), but there was no significant correlation in adenoma (P = 0.973). Sixteen (94.1%) of 17 seropositive adenocarcinoma patients, showed negative conversion after complete tumor resection, and all these 16 patients remained seronegative.

CONCLUSION

The detection of serum p53 antibody is expected to serve as a new genetic marker, determined by serological analyses, for aiding in the early diagnosis of superficial colorectal cancer and indicating its local curability after endoscopic treatment.

[Continuous nursing of incurable patients at home--the case of a patient with Parkinson's disease]

At the Department of Neurology and Internal Medicine at our hospital, there are 22 outpatients who are nursed at home. Their diseases are Parkinson's disease, spinal cerebellar degeneration, dementia and other diseases. The problem is how we should care for and support these patients in the future, now that the official Care Insurance System has started. We discuss how we could support such patients, through the case of a patient suffering from Parkinson's disease. The patient was a 69-year-old female. In 1991, she developed Parkinson's disease, accompanied with trembling in her right upper limb. Her condition was controlled at our hospital. Is April 1999, she lost strength in her right thigh without any previous notice, so she was hospitalized for treatment. For a period, she became aggressive from hallucinations and delusions and she had to be taken care of all day. Her only daughter lived apart and her 72-year-old husband was also suffering from Parkinson's disease. In spite of such conditions, she hoped to receive home care and her husband accepted that. We asked what they would want us to do. We had meetings together with the staff of the local administration, doctors, nurses, and pharmacists. The report from our hospital staff says, "It may be difficult for only her family to support her. She needs other supporting systems." She came to our hospital twice a month. We made an effort to understand her condition with the help of the report of a visiting nurse. However, her illusions and delusions made it difficult even to utilize the short-stay. Her husband sometimes uses violence and says. "I can't stand this any more--her unrest, micturition at night and refusal to eat." Nevertheless, she continues to say "I want to stay at home." They have had considerable trouble. The following are necessary for home care of some patients. 1. Understanding what a patient and her family want to do. Cooperating with the staff of the administration, in consideration of the Care Insurance System. 2. Studying with incurable neurology patients using pamphlets or other materials and supporting them, 3. Discussing how to act in concert with patients at home and outpatients at the hospital involving a risk without MSW.

Increased phospholipase D2 activity during hypoxia-induced death of PC12 cells: its possible anti-apoptotic role

During hypoxic incubation (1% O2) of PC12 cells, the PLD activity was transiently increased within 12h, followed by a gradual decrease. In the in vitro assay, the increased PLD activity was independent of GTPgammaS required for PLD1 or of oleic acid for PLD(OA), suggesting the activation of PLD2. The level of PLD2 protein showed no change up to 12h but a gradual decrease after 24 h. Pretreatment of cells with S. chromofuscus PLD resulted in inhibition of hypoxia-induced apoptotic cell death. In contrast, 1-butanol, but not 2-butanol, potentiated cell death. Moreover, the number of apoptotic cells significantly reduced in PC12 cells over-expressing PLD2. These results raise the possibility that PLD2 activation may play an anti-apoptotic role in hypoxia-induced cell death.

[Long-term results of right ventricular outflow reconstruction with valved conduit]

Twenty-nine patients who underwent right ventricular outflow tract reconstruction using a valved conduit 37 times and survived surgery, were reviewed in this study. Hancock, Ionescu-Shiley, Carpentier-Edwards and Polystan was used for RVOTR. Freedom from reoperation rates of Hancock, Ionescu-Shiley and Carpentier-Edwardsat at five and ten years after surgery were 100%, 85.7%, 89.2% and 75%, 28.6%, 89.2%, respectively. The freedom from reoperation rates of Hancock and Carpentier-Edwards were significantly higher than that of Ionescu-Shiley. In conclusion, the freedom from reoperation rate at ten years was high for both Hancock and Carpentier-Edwards.

Effect of butyl benzyl phthalate in Sprague-Dawley rats after gavage administration: a two-generation reproductive study

Butyl benzyl phthalate (BBP), a plasticizer, has been shown in in vitro studies to be weakly estrogenic, and in in vivo studies to possess testicular toxicity and teratogenicity, but few experimental data on BBP multigeneration effects on reproduction in mammals are available. The present two-generation reproductive study was conducted in male and female Sprague-Dawley rats using oral doses of 0, 20, 100, and 500 mg/kg/day BBP. Endpoints were chosen in order to evaluate both subchronic and reproductive toxicity. In the parent animals (F(0)), a decrease in body weight gain was observed in males in the 500 mg/kg/day group, although no significant decrease in food consumption was found. No dose-related changes were observed in estrous cyclicity, fertility, or lactation. A dose-dependent increase in kidney weight in rats of both sexes, an increase in liver weight in males, and a decrease in the weight of the ovaries in females were observed. No macroscopic or microscopic changes were found in the reproductive system of males or females. Oral administration of BBP caused a decrease in the serum concentration of testosterone, and an increase in FSH. In the next generation (F(1)), the body weight of male and female offspring at birth in the 100 and 500 mg/kg groups was significantly decreased, and the body weight in the 500 mg/kg group was lower throughout the study, while viability was not affected. Anogenital distance (AGD) at birth was decreased in male pups and was increased in female pups of the 500 mg/kg/day group. Preputial separation for male offspring in the 500 mg/kg/day group was delayed, while vaginal opening for female offspring in this group was not affected. BBP did not affect reproductive ability, including delivery and lactation, at any dose whereas macroscopic and microscopic changes of the testis, and decreased serum concentrations of testosterone were observed in male offspring of the 500 mg/kg/day group after puberty. From these data, it would appear that 20 mg/kg BBP is a no observed adverse effect level (NOAEL) for reproductive effects on parent animals and the next generation.

Expression of pituitary homeo box 1 (Ptx1) in human non-neoplastic pituitaries and pituitary adenomas

We investigated the localization of pituitary homeo box 1 (Ptx1) protein in five human non-neoplastic pituitaries and 73 of all types of pituitary adenomas using immunohistochemistry, and the expression of Ptx1 messenger RNA (mRNA) in 18 representative pituitary adenomas using the reverse transcriptase polymerase chain reaction (RT-PCR) technique. By immunohistochemical analysis, Ptx1 protein was extensively detected in the nuclei of normal human pituitary cells. Ptx1 was detected in 10/14 (71.4%) of growth hormone (GH)-secreting adenomas, 12/12 (100%) of prolactin (PRL)-secreting adenomas, 18/20 (90%) of adrenocorticotropic hormone (ACTH)-secreting adenomas, 6/7 (85.7%) of thyroid-stimulating hormone (TSH)-secreting adenomas, and 17/20 (85%) of clinically non-functioning adenomas, including 9/10 (90%) of gonadotropin-subunit-positive adenomas. Thus, there was no relationship between Ptx1 expression and a particular type of pituitary adenomas. By RT-PCR analysis, Ptx1 mRNA was expressed in all 18 cases of pituitary adenomas, including two cases negative for Ptx1 protein by immunohistochemistry. These results suggested that Ptx1 may be an universal transcription factor in both neoplastic and non-neoplastic conditions in human pituitaries. The synergistic action with other transcription factors may be speculated to determine the specific production of the anterior pituitary hormones.

High concentrations of serum inhibin in pre-eclampsia

OBJECTIVE

To evaluate maternal serum immunoreactive inhibin (ir-inhibin) concentrations in women with pre-eclampsia, and assess the correlation between serum ir-inhibin and HCG.

METHODS

The subjects comprised 28 pregnant women with suspected intrauterine growth retardation (IUGR) during the third trimester. Serum concentrations of ir-inhibin and HCG were measured in 13 women with pre-eclampsia and 15 pregnant women as control subjects. Serum ir-inhibin was determined by a double antibody radioimmunoassay, and HCG by a solid-phase immunoradiometric assay.

RESULTS

There were no significant differences in maternal characteristics between the pre-eclamptic group and control group. The pre-eclamptic group had significantly higher concentrations of serum ir-inhibin and HCG compared with the control group. The serum concentrations of ir-inhibin correlated positively with those of HCG.

CONCLUSION

The pre-eclamptic patients displayed high serum levels of ir-inhibin and HCG, and this might reflect hyperplasia of trophoblastic cells.

Activation of caspase-9 and -3 during H2O2-induced apoptosis of PC12 cells independent of ceramide formation

The treatment of PC12 cells with H2O2 (100-500 microM) resulted in typical apoptotic changes including fragmentation and condensation of nuclei, and DNA fragmentation observed as DNA ladder. H2O2-induced apoptosis was associated with activation of caspase-3 as assessed by cleavage of specific fluorogenic substrate peptide and processing of procaspase-3 and poly(ADP-ribose) polymerase. However, formation of ceramide, which often locates upstream of caspase-3, was not observed. The inhibitory peptide relatively specific for caspase-3, z-DEVD-FMK and non-selective caspase inhibitor z-VAD-FMK inhibited activation of caspase-3 and apoptotic cell death. However, the relatively specific inhibitors, Ac-YVKD for caspase-1 and Ac-IETD for caspase-8/6, did not affect the occurrence of apoptotic cell death. As an upstream activation of caspase-3, induction of cytochrome c release followed by processing of procaspase-9 was observed by Western blotting, although the formation of intracellular ceramide was not observed. On the other hand, in PC12 cells overexpressing Bcl-2, the number of apoptotic cells was markedly decreased and activation of both caspases-9 and -3 was prevented. These results suggest that cytochrome c and caspase-9 initiate the activation of executor caspase-3 in H2O2-treated PC12 cells, and that Bcl-2 inhibits H2O2-induced release of cytochrome c from mitochondria and then proteolytic processing of procaspase-9.

[Long-term effect of polystan monocusp ventricular outflow patch after right ventricular outflow tract reconstruction]

Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.

Analyses of virus-induced homomeric and heteromeric protein associations between IRF-3 and coactivator CBP/p300

Cellular genes including the type I interferon genes are activated in response to viral infection. We previously reported that IRF-3 (interferon regulatory factor 3) is specifically phosphorylated on serine residues and directly transmits a virus-induced signal from the cytoplasm to the nucleus, and then participates in the primary phase of gene induction. In this study, we analyzed the molecular mechanism of IRF-3 activation further. The formation of a stable homomeric complex of IRF-3 between the specifically phosphorylated IRF-3 molecules occurred. While virus-induced IRF-7 did not bind to p300, the phosphorylated IRF-3 complex formed a stable multimeric complex with p300 (active holocomplex). Competition using a synthetic phosphopeptide corresponding to the activated IRF-3 demonstrated that p300 directly recognizes the structure in the vicinity of the phosphorylated residues of IRF-3. These results indicated that the phosphorylation of serine residues at positions 385 and 386 is critical for the formation of the holocomplex, presumably through a conformational switch facilitating homodimer formation and the generation of the interaction interface with CBP/p300.

Developmental toxicity of the topoisomerase inhibitor, etoposide, in rabbits after intravenous administration

The developmental effect of the topoisomerase inhibitor, etoposide, was investigated in pregnant rabbits given intravenous doses during early organogenesis. Does received 0, 0.25, 0.5, 1, or 2 mg/kg/day on days 7 through 9 of gestation. Fetal parameters were evaluated on day 28 of gestation. Live fetuses were examined for gross, visceral, and skeletal malformations and variations. In addition, telencephalon in embryos 8 h following the final treatment was examined histologically. No change in general condition was observed in any does, but a significant decrease in body weight gain during the pregnancy and enlargement of the liver resulting from marked fatty change were observed in does treated with etoposide at 2 mg/kg/day. Etoposide had neither lethal nor growth retarded effects on embryos/fetuses. However, axial skeletal malformation and extra ribs had a low incidence but were significant in the group treated with etoposide at 2 mg/kg/day, whereas no significant increases in external malformations in term fetuses nor in pyknotic cells in the ventricular zone of telencephalon in embryos were noticed in any etoposide-treated groups. It was concluded that anatomical defects (skeletal malformation or variation) in rabbits were induced by intravenous etoposide treatment during early organogenesis and that they occurred in the presence of maternal toxicity.

Touch-free in situ investigation of ancient Egyptian pigments

Some of the pigments painted on the Funerary Stele of Amenemhat (ca. 2000 B.C.) exhibited at the Egyptian Museum, Cairo and on the walls of the Tomb of Userhat (ca. 1420 B.C.), a rock-cut tomb in Thebes, Egypt, were investigated in situ using both a convenient home-made hand-held type of X-ray diffractometer and a commercial X-ray fluorescence spectrometer in a complementary way under touch-free conditions. CaCO3.3MgCO3 (huntite) was found in the white-painted parts of these two ancient monuments. An arsenic (As)-bearing phase was detected in the yellow-painted parts of the latter monument. The occurrence of huntite in Egypt has not been reported previously.

[Coil embolization for incidental aneurysms in patients with chronic renal failure: midterm clinical results of two cases]

In spite of recent advances in perioperative management, the risk of neurosurgical intervention for patients with chronic renal failure is still considered too high. In this study, coil embolization for incidental aneurysms in such patients is demonstrated in reference to midterm results. A 42-year-old woman with a history of hemodialisis for 7 years presented with subcortical hemorrhage in her right frontal lobe. The magnetic resonance angiography (MRA) demonstrated a distal anterior cerebral artery aneurysm, but it was considered to be unrelated to the hemorrhage. Two and a half months after the hemorrhage the aneurysm was embolized with interlocking detachable coils. Thirty months after embolization, the angiogram revealed the coil compaction and the recanalization of the aneurysm neck. However, 54 months after embolization, the figure of the embolized aneurysm and neck remnant was the same as the previous findings. A 69-year-old woman with a history of hemodialisis for 5 years suddenly experienced left hemiparesis. Computed tomography revealed cerebral infarction in the right frontoparietal white matter. In addition, a left middle cerebral artery aneurysm was unexpectedly found on the MRA. Five months after the onset of the attack, the aneurysm was embolized with a Guglielmi detachable coli. An angiogram obtained 24 months after the embolization showed the aneurysm to be almost completely obliterated. In considering the therapeutic risks and benefits for incidental aneurysms of patients with chronic renal failure, intra-vascular surgery could be recommended as a less invasive treatment.

[Forecast of total pollen counts of sugi (Cryptomeria japonica) from the amount of male flower development and the revised total pollen counts]

We have successfully forecast the total pollen counts of sugi (Cryptomeria japonica) since 1996 by the amount of male flower development. The amount of male flower development was observed at 11 forests in the Tanba Mountains and 10 forests in the Chugoku Mountains depending on both in Hyogo Prefecture. The amount of male flower development on each tree was assigned to one of five classes by the number of male flowers per spring. After a large harvest of male flowers, the production of male flowers declined in the following years, especially at high altitudes. It was also followed by a decrease in the number of airborne pollen grains in the later pollen season. According to an analysis of weather conditions, total pollen counts were correlated with the high temperature between July 6 and 20 and the total pollen counts of the previous season. However, the amount of male flower development was the most significant indicator for forecasting total pollen counts. Decrease in total pollen counts due to abnormal weather during the pollen season was correlated with discrepancies in forest flowering time according to observations made in the Rokko Mountains. Increase in total pollen counts was connected by a development of the sugi forest areas. Twenty percent of mature sugi forests from 1992 which showed an annual increase were associated with an increase in total pollen counts. The accuracy of the forecast was improved by revising the total pollen counts for weather conditions during the dispersion stage, a decrease in the production of male flowers at high altitude, and an increase in the production of male flowers connected by a developing forest areas.

Limited myogenic response to a single bout of weight-lifting exercise in old rats

The purpose of the present study was to compare the myogenic response of hindlimb muscles in young (14-20 wk of age) and old (>120 wk of age) rats with a single exhaustive bout of heavy resistance weight lifting. [(3)H]thymidine and [(14)C]leucine labeling were monitored for up to 2 wk after the exercise bout to estimate serial changes in mitotic activity and the level of amino acid uptake and myosin synthesis. Histological, histochemical, and immunohistochemical [anti-5-bromo-2'-deoxyuridine and myogenic determination genes (MyoD)] analyses of whole muscles and analysis of muscle-specific gene expression (MyoD) using Western blotting and RT-PCR were performed. Old rats showed significant muscle atrophy and a lower exercise capacity than young rats. Exercise-induced muscle damage, as assessed in histological sections, and increases in serum creatine kinase activity were evident in both young and old exercised groups. Mitotic activity was increased in young, but not old, rats 2 days after exercise. There was a biphasic increase in [(14)C]leucine uptake during the 14 days postexercise (peaks at 1-4 and 10 days) in young rats: only the first peak was observed in old rats. There was a lower uptake of [(14)C]leucine in the myosin fraction and an impaired expression of MyoD at the protein (immunohistochemistry and Western blotting) and mRNA (RT-PCR) levels in old rats throughout the postexercise period. These results demonstrate a reduced reparative capability of muscle in response to a single bout of exercise in old compared with young rats.

A new antimitotic substance, FR182877. III. Structure determination

During the course of screening for novel cell cycle inhibitors, FR182877 was isolated from the fermentation broth of Streptomyces sp. No.9885. During the NMR measurements, FR182877 decomposed so much that the structure elucidation of FR182877 itself was difficult. Then, combinations of chemical correlations and spectroscopic methods clarified that FR182877 possesses an unprecedented multi-ring system including the strained double bond, which was unexpectedly epoxidized by molecular oxygen. FR182877 showed broad antitumor activities in vitro and promoted assemblies of tublins in vitro as well as taxol. It is noteworthy that epoxidation of the distorted double bond resulted in significant decrease in antitumor activities.

Elevation of mRNA levels of tissue-type plasminogen activator and urokinase-type plasminogen activator in hippocampus and cerebral cortex following middle cerebral artery occlusion in rats

Tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA) have been used for thrombolitic therapy. In contrast, it is suggested that these compounds might be involved in neuronal cell damage. The activation and the function of tPA and uPA are less understood in ischemic brain tissue. Therefore, changes in tPA and uPA mRNA in rat brain tissue after MCA occlusion and in the neuronal cell line, PC12 cells, during the hypoxic stimulation were examined. Permanent middle cerebral artery (MCA) occlusion was induced by advancing a filament into the internal carotid artery in 36 adult male Sprague-Dawley rats. The ischemic cerebral cortex and contralateral cortex of MCA area, and bilateral hippocampus were collected at 0 (controls), 1, 3, 6, 12 and 24 h after occlusion. Hypoxia was induced in PC12 cells with a multigas incubator (set to 1% O2). The quantitative reverse transcription-polymerase chain reaction acted as a measurement of alteration in mRNA levels. The mRNA levels of tPA and uPA were significantly increased after MCA occlusion in the ischemic cerebral cortex. The magnitude of the increase in tPA and uPA mRNA in 24 h after occlusion was twice the value in sham-operated rat (0 h). The increases of tPA mRNA were time-dependent in insult and contralateral hippocampus. The increase of uPA mRNA was also seen in the hippocampus bilaterally, although the increase was more significant on the ipsilateral side. In PC12 cells, necrotic (approximately 35%) and apoptotic cells (approximately 65%) could be distinguished by hypoxic stimulus for 24 h, and the mRNA for tPA was significantly increased for 6 h-12 h, while the mRNA for uPA was not detected at any point in the study. Our results suggest that focal ischemia might result in the activation of these proteases not only in the insult but also in the contralateral brain tissue.

Effects of lentinan on colorectal carcinogenesis in mice with ulcerative colitis

Lentinan; i.e., polysaccharides extracted from a kind of black mushroom shiitake, has been clinically applied as an antitumor and antimetastatic drug, and has been reported to prevent both chemical and viral carcinogenesis. It is known that lentinan affects the tumorous vascular system resulting in the induction of hemorrhagic necrosis which is dependent on T-cells in the tumor. Repeated mucosal necrosis-regeneration sequence in chronic ulcerative colitis induced with 3% dextran sulfate sodium led to colorectal carcinogenesis in azoxymethane-pretreated mice. In the present study, the additive treatment with lentinan in the azoxymethane-dextran sulfate sodium treated mice enhanced the colorectal high-grade dysplasia, though not significantly, and the splenic weight. This may show the proliferation of pathogenic splenic T cells resulting in a change for the worse of ulcerative colitis, anemia induced with hemorrhage and colorectal carcinogenesis; i.e., high-grade dysplasia of the mucosa and/or invasive adenocarcinomas of the colorectum. The present results may recommend chemoimmunotherapy while using lentinan, but not immunotherapy using lentinan alone, is indicated for the management of cancer patients.

Disruption of the reproductive system and reproductive performance by administration of nonylphenol to newborn rats

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 few in vivo data are 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. The reproductive function of rats treated subcutaneously with nonylphenol (NP, 500 mg/kg/day) or 17beta-estradiol (E2, 2 mg/kg/day) as a positive control, from postnatal days 1 to 5 was examined after puberty. In addition, masculine sexual behavior, sperm motion, plasma testosterone concentration and histopathological changes in the reproductive organs of the rats were examined. Furthermore, male rats were subjected to an open field test and wheel cage test to evaluate locomotor activity, and the estrous cycle was examined in female rats. All male and female rats exposed neonatally to NP or E2 showed macroscopic and/or microscopic alterations of the gonads. Females treated with NP or E2 showed an altered estrous cycle and abnormal reproductive function, while males treated with NP or E2 showed normal reproduction. In males exposed neonatally to NP or E2, no abnormalities were observed in locomotor activity, sperm motion or plasma testosterone concentration. The results of this study indicate that early neonatal exposure to NP causes dysfunction of postpubertal reproductive function in female rats, as well as disrupted development of gonads in male and female rats. More detailed studies are warranted to assess the possible risks to human and wildlife reproduction from exposure to NP and other environmental chemicals with estrogenic activity.

Possible mechanism of congenital malformations induced by exposure of mouse preimplantation embryos to mitomycin C

ICR mice were treated intraperitoneally with mitomycin C at 5 mg/kg on day 3 of gestation. On day 18 of gestation, fetuses of treated dams were inspected for external, skeletal and visceral malformations. At 6 or 12 hr after mitomycin C treatment, the blastocysts were obtained from the uteri of treated dams and the degenerated cells within inner cell mass (ICM) and trophectoderm (TE) tissues were examined microscopically. On day 5, 8, 11, or 18 of gestation, the uteri of treated dams were obtained and those including embryos/fetuses and placentae were examined histologically. Finally, on each of gestational days 5-14, the blood of the treated dams was collected and the hematological parameters determined. Pre- and postimplantation losses in the dams treated with mitomycin C were significantly increased; increased frequency of abdominal wall defects and lumbar ribs in term fetuses, decreased fetal weight, and increased placental weight were noted as well. No significant increase in visceral malformations was found in term fetuses treated with mitomycin C. Frequency of degenerated cells within ICM and TE of blastocysts from dams treated with mitomycin C was significantly increased as compared with the controls. In dams treated with mitomycin C, decidua developed insufficiently and the trophoblast giant cell layer was not separated from the uterine lumen by maternal components; hemorrhage from the denuded trophoblast giant cell layer into the uterine lumen was noted. The number of erythrocytes, as well as hemoglobin concentration, hematocrit, and the percentage of reticulocytes in blood of dams treated with mitomycin C were significantly lower from days 6-12 of gestation, as compared with controls. The results of the present study showed that an increase in number of degenerated cells within blastocysts results in preimplantation loss and both maternal and embryonic hypoxia during major organogenesis results in postimplantation loss and congenital fetal malformations.

[Improved gastric patch method for esophagocardioplasty in esophageal achalasia]

We performed esophagocardioplasty with the gastric patch (original GP) as the treatment of first choice in patients with esophageal achalasia. However, postoperative reflux esophagitis occurred in many due to secretory dysfunction of the gastric mucosa implanted in the mediastinum. We therefore developed two modifications of the gastric patch technique (GP II and GP III) which do not involve implantation of the gastric mucosa in the esophagus. Twenty-three patients have undergone the modified GP II procedure in our institution. Postoperative changes in the esophagus were examined fluoroscopically, and it was found that esophageal diameter increased from an average 2.9 +/- 0.6 cm to 5.2 +/- 1.0 cm at an average follow-up of 7.1 months (p < 0.01). All 23 patients experienced amelioration of symptoms, even though some reddening was still present in the lower esophagus, with a maximum follow-up of 8 years. Based on these results, the modified GP procedures are an acceptable open surgery modality for esophagocardioplasty in esophageal achalasia.

Long-term ethanol consumption in ICR mice causes mammary tumor in females and liver fibrosis in males

BACKGROUND

Although epidemiological studies indicate that ethanol consumption and the risk of breast cancer are positively associated in women, experimental animal models have not yet been developed that provide evidence to support this relationship. To clarify alcohol-related liver injury, it is important to reproduce, in laboratory small animals, the liver fibrosis observed in human alcoholics. However, in mice the induction of fibrosis has failed. The present study describes the first experimental models to produce mammary tumors in female ICR mice and liver fibrosis in male ICR mice treated long-term with ethanol.

METHODS

The study consisted of two parts. To induce mammary tumors, female ICR mice were given 10% to 15% ethanol solution as the sole drinking fluid for 25 months, with solid diet supplied ad libitum. To induce liver fibrosis, male ICR mice were given 10% to 15% ethanol solution as the sole drinking fluid for 10 to 15 months. Control female and male mice were given tap water.

RESULTS

In 9 (45%) of 20 ethanol-treated female mice, mammary tumors occurred at 8 to 24 months after ethanol intake began, whereas spontaneous mammary tumor was not found in the 20 control female mice. The tumors were composed histopathologically of either papillary adenocarcinoma or medullary adenocarcinoma of glandular epithelial origin. In the ethanol-treated male mice, early hepatic fibrosis at the centrilobular and pericellular areas and central-central bridging were observed at the 10th month, and marked fibrosis at the centrilobular, pericellular, and periportal areas and bridging between the neighboring vascular tissues were observed at the 15th month, which suggested that the initial fibrosis arose from the centrilobular area. No abnormalities other than mild fatty infiltration were found in livers of the control male mice.

CONCLUSIONS

These murine models may be useful to study the role of ethanol in mammary tumorigenesis and the pathogenetic mechanisms of ethanol liver injury.

Predicting incomplete uterine rupture with vaginal sonography during the late second trimester in women with prior cesarean

OBJECTIVE

To evaluate the usefulness of serial transvaginal ultrasonographic measurement of the thickness of the lower uterine segment in the late second trimester for predicting the risk of intrapartum incomplete uterine rupture in women with previous cesarean delivery.

METHODS

Serial transvaginal ultrasonography with full bladder was performed in 374 women without previous cesarean delivery (control group) and 348 women with previous cesarean delivery (cesarean group) from 19 to 39 weeks' gestation. The thickness of the lower uterine segment was measured in the longitudinal plane of the cervical canal.

RESULTS

The thickness of the lower uterine segment decreased from 6.7 +/- 2.4 mm (mean +/- standard deviation [SD]) at 19 weeks' gestation to 3.0 +/- 0.7 mm at 39 weeks' gestation in the control group, but the thickness was more than 2.0 mm throughout this period in each control subject. In the cesarean group, the thickness decreased from 6.8 +/- 2.3 mm at 19 weeks' to 2.1 +/- 0.7 mm at 39 weeks' gestation and was significantly thinner than that of the control group after 27 weeks' gestation (P <.05). Eleven of 12 women (91%) with lower uterine segment less than the mean control - 1 SD in the late second trimester had a very thin lower uterine segment at cesarean delivery with fetal hair being visible through the amniotic membrane, ie, incomplete uterine rupture. In 17 of 23 women (74%) with lower uterine segment less than 2.0 mm in thickness within 1 week (4 +/- 3 days) before repeat cesarean delivery, intrapartum incomplete uterine rupture developed.

CONCLUSION

Transvaginal ultrasonography is useful for measurement of the uterine wall after previous cesarean delivery.

beta-blocker therapy in patients after aortic valve replacement for aortic regurgitation

BACKGROUND

beta-blocker therapy for dilated or ischemic cardiomyopathy is now an accepted and effective treatment. However, little is known about its efficacy in patients with postoperative impaired left ventricular function. This retrospective study was designed to assess the effects of beta-blocker therapy in patients after aortic valve replacement (AVR) for aortic regurgitation (AR).

METHODS

A total of 59 patients who underwent AVR for chronic AR were assigned to four groups. Twelve patients were treated with both ACE inhibitors and beta-blockers, 12 patients with only ACE inhibitors, eight patients with only beta-blockers, and 27 patients without beta-blockers or ACE inhibitors. A postoperative echocardiographic study was performed one year after surgery.

RESULTS

The heart rate was significantly reduced in patients with beta-blockers despite the use of ACE inhibitors after surgery. Postoperative left ventricular volume was more significantly decreased in beta patients than in non-beta patients despite the use of ACE inhibitors. There were also significant reductions in left ventricular mass index in ACE+beta patients compared to ACE+non-beta patients. However, there were no significant differences in NYHA functional class and survival rate between beta patients and non-beta patients.

CONCLUSIONS

beta-blocker therapy may improve cardiac performance by reducing cardiac volume and mass in patients with impaired LV function after AVR for AR.

Survival-promoting activity of IL-7 on IL-2-dependent cytotoxic T lymphocyte clones: resultant induction of G1 arrest

Interleukin-7 (IL-7) is essential for both T cell and B cell development. Recent studies have suggested that IL-7 also functions as a survival-promoting factor for resting and activated T cells. In this study we examined the effects of IL-7 on survival and cytotoxicity of tumor-specific CD8(+) cytotoxic T lymphocyte (CTL) clones established and maintained either with IL-2 alone or with a combination of IL-2 and IL-7. While the CTL clones cultured in IL-2 alone died around day 10, the CTL clones cultured in the presence of IL-2 and IL-7 survived for more than 4 weeks after seeding. The long-term survival of the latter was correlated with the presence of IL-7 in the medium. In addition, IL-7 alone prolonged survival of other IL-2-dependent CTL clones after the removal of IL-2. IL-7 maintained the CTLs in G1 arrest after a slight proliferation during the initial phase during which low-level but sustained DNA synthesis was observed. However, there was no direct correlation between DNA synthesis and enhancement of long-term survival by IL-7 as demonstrated by the inhibiting proliferation of the CTL clones with the protein kinase inhibitor genistein. During long-term survival in the presence of IL-7, the cytotoxic activities of the CTL clones decreased gradually to background levels although they were restored soon after the next passage. These results suggested that IL-7 had the ability to set machinery in motion against apoptosis in the IL-2-dependent CTL clones. Such an effect of IL-7 might play a role in vivo in the process leading activated T cells to the resting, that is, memory state.

Treatment for abdominal aortic graft infection: irrigation with electrolyzed strong aqueous acid, in-situ grafting, and omentoplasty

We report on successful surgical treatment of consecutive three patients with infection of an abdominal aortic graft, Therapy involved a combination of removal of the infected graft, elaborate debridement, irrigation with electrolyzed strongly acidic aqueous solution (ESAAS), in-situ regrafting, and omentoplasty. The use of ESAAS is discussed.

Effect of epidermal growth factor on lung growth in experimental fetal pulmonary hypoplasia

The purpose of this study was (1) to compare the expression of epithelial growth factor receptor (EGFR) in the lung tissues of human fetuses with or without pulmonary hypoplasia, and (2) to investigate the effects of EGF on lung growth in experimental pulmonary hypoplasia in rabbits. Firstly, we investigated the expression of EGFR in lung tissues of human fetuses with or without pulmonary hypoplasia by immunohistochemistry. Secondly, the amniotic fluid was shunted into the maternal abdominal cavity in a group of 12 fetal rabbits, another group (n = 12) received EGF injection (5 microg, i.p.) at day 25 of gestation. The third group (n = 12) was only treated with EGF while littermates not operated on served as the control group (n = 12). On day 29 of gestation, fetuses were delivered by Cesarean section and the lungs removed. The body weight and wet lung and liver weights were measured. As a measure of fetal lung growth, we determined the size of lung acini, the number of terminal airspaces, and diameter of alveoli (n = 6, each groups). We also measured the concentration of phosphatidylcholine (PC) and the lecithin/sphingomyelin (L/S) ratio in lung lavage fluid at birth in some fetuses (n = 6, each groups). In human fetuses with pulmonary hypoplasia, there was a significant decrease in radial alveolar count and expression of EGFR compared with fetuses without pulmonary hypoplasia. Amniotic shunt significantly decreased fetal lung/body weight ratio compared with control. Injection of EGF in the shunted group significantly increased lung/body weight ratio to the control level. The concentration of PC and L/S ratio in lung fluid lavage from rabbit fetuses with hypoplastic lungs was significantly higher than the other three groups. Histopathological examination of fetuses with hypoplastic lungs treated with EGF showed no significant change in the size of acini, number of terminal airspaces or the diameter of alveoli compared with the control group. Our results suggested that EGF was associated with lung growth and maturation of human lung and that treatment of rabbit fetuses with hypoplastic lungs with EGF facilitated lung growth and development.

Combined cardiac surgery and total thyroidectomy: a case report

A 65-year-old woman with aortic stenosis, ischemic heart disease, and Graves' disease had complained of effort angina. She then suffered from liver dysfunction due to treatment with antithyroid drugs. One year after the start of radioiodine administration, she demonstrated unstable angina with palpitation and sweating. Laboratory studies revealed a recurrent hyperthyroid state, and a second coronary angiogram revealed progressive ischemic heart disease. Combined coronary artery bypass grafting, aortic valve replacement, and total thyroidectomy were performed. The postoperative course was uneventful without any problems associated with hyperthyroidism or hypothyroidism. Combined cardiac surgery and total thyroidectomy can be performed safely if the perioperative levels of thyroid hormone are maintained at euthyroid or hypothyroid levels.

Correlation between histological differentiation and DNA-synthesizing enzymes in rat colorectal tumors induced with 1, 2-dimethylhydrazine

Thymidylate synthase and thymidine kinase are key enzymes involved in de novo and salvage pathways for pyrimidine nucleotide synthesis. Colorectal carcinogenesis induced with 1,2-dimethylhydrazine in rats enhanced mRNA expression levels of both enzymes, resulting in the increase of both enzyme activities and bromodeoxyuridine-immunoreactive S-phase cells. Poorly and well differentiated adenocarcinomas of the colorectum showed the relative elevation of activities of thymidylate synthase and thymidine kinase, respectively. These results indicate that the relationship between de novo and salvage pathways for pyrimidine nucleotide synthesis may depend on the histopathological grades of cell differentiation.

Effects of long-term administration of UFT plus leucovorin on colorectal tumors induced with 1,2-dimethylhydrazine in rats

Thymidylate synthase and thymidine kinase are key enzymes involved in the de novo and salvage pathways for pyrimidine nucleotide synthesis, respectively. Thymidylate synthase is inhibited by 5-fluorodeoxyuridine monophosphate, forming an inactive ternary complex with intracellular folate. We investigated the effects of 1-(2-tetrahydrofuryl)-5-FU plus uracil (UFT) with or without leucovorin on 1,2-dimethylhydrazine-induced rat colorectal carcinomas. Thirty-week administration of UFT with or without leucovorin markedly suppressed both colorectal carcinogenesis and tumor growth, resulted in the increase of thymidylate synthase inhibition and the decrease of thymidine kinase activity in the tumor cells. These results indicate that the combination of UFT with leucovorin could be useful in the development of pre- and post-operative adjuvant chemotherapy programs.