Ruptured thrombosed vertebral artery dissecting aneurysm treated with staged flow diverter after prediction of the rupture point by vessel wall MRI

The safety and feasibility of using staged flow diverter (FD) for ruptured cerebral aneurysms, in which coil embolization is performed in the acute phase and FD is deployed in the subacute phase, has recently been reported. This strategy requires assuming the rupture point and performing coil embolization. Although vessel wall magnetic resonance imaging (VW-MRI) has been reported to be useful in predicting the rupture point of aneurysms, its use with staged FD has not yet been reported. We report the first case of staged FD with preoperative contrast-enhanced VW-MRI to predict the rupture point for partially thrombosed vertebral artery dissecting large aneurysm involving posterior inferior cerebellar artery (PICA) origin. This approach achieved a very good outcome, not only completely occluding the aneurysm, but also reconstructing the parent artery while maintaining the patency of the PICA.

Predictors of aneurysm shrinkage after flow diversion treatment for internal carotid artery aneurysms: quantitative volume analysis with MRI

Background and purpose

Although aneurysm shrinkage often occurs after flow diversion treatment for intracranial aneurysms, no reports have addressed the factors associated with aneurysm shrinkage.

Materials and methods

This retrospective single-center study was performed to examine patients with unruptured internal carotid artery aneurysms who were treated using flow diversion and followed up by imaging for at least 12 months. The study outcome was aneurysm shrinkage (volume reduction of ≥10%) 12 months after treatment. Aneurysm volume was quantitatively assessed using the MRIcroGL software. Patient and aneurysm characteristics were statistically analyzed.

Results

This study involved 81 patients with 88 aneurysms. At the 6 months, 12 months, and last follow-ups, the proportion of aneurysms that had shrunk was 50, 64, and 65%, respectively. No adjunctive coiling (odds ratio, 56.7; 95% confidence interval, 7.03-457.21; p < 0.001) and aneurysm occlusion (odds ratio, 90.7; 95% confidence interval, 8.32-988.66; p < 0.001) were significantly associated with aneurysm shrinkage. In patients treated by flow diversion with adjunctive coiling, only the volume embolization rate was a factor significantly associated with aneurysm shrinkage (p < 0.001). Its cutoff value was 15.5% according to the receiver operating characteristic curve analysis (area under the curve, 0.87; sensitivity, 0.87; specificity, 0.83).

Conclusion

The rate of aneurysm shrinkage after flow diversion increased during the first 12 months after treatment, but not thereafter. No adjunctive coiling and aneurysm occlusion were predictors of aneurysm shrinkage, respectively. If adjunctive coiling is required, a volume embolization rate of ≤15.5% may be suggested for aneurysm regression.

Partially thrombosed giant basilar artery aneurysm with attenuated contrast enhancement of the intraluminal thrombus on vessel wall MRI after flow diversion treatment: illustrative case

BACKGROUND

The effect of vessel wall magnetic resonance imaging (VW-MRI) enhancement in partially thrombosed aneurysms has previously indicated aneurysmal instability and a rupture risk. However, whether the contrast effect of the wall changes before or after flow diversion treatment is still under investigation.

OBSERVATIONS

The authors report a case of a partially thrombosed basilar artery aneurysm that increased in size over a short period, worsened brainstem compression symptoms, and was treated with a flow diverter stent with good results. In this case, VW-MRI after surgery showed a reduced contrast effect on the intraluminal thrombus within the aneurysm. The aneurysm thrombosed and markedly regressed over the next 5 months, with remarkable improvement in the brainstem compression symptoms.

LESSONS

This finding on VW-MRI may indicate an attenuation of neovascularization in the thrombus wall and be a sign of aneurysm stabilization.

Cone-beam CT-assisted microcatheter tip placement at the shunted pouch entry zone: A technical note for anterior condylar arteriovenous fistula

Accurate microcatheter placement for anterior condylar arteriovenous fistula (AVF) enables selective transvenous embolization (TVE) and helps to avoid hypoglossal nerve palsy. Anterior condylar AVF has a shunted pouch within the condylar vascular and osseous structures. Detailed anatomical comprehension of the shunted pouch is essential, in addition, we believe that it is important to have a strategy for where in the shunted pouch to start filling with coils. Specifically, we consider that it is important to structurally understand the more upstream location (arterial side) within the shunted pouch (called "shunted pouch entry zone"), guide the microcatheter there, and embolize from that site. Although several studies have discussed the usefulness of intraoperative cone-beam computed tomography (CBCT) for treating anterior condylar AVF, there are no studies which have mentioned the importance of microcatheter position before coil embolization in selective TVE as in this study. Intraoperative localization of the shunted pouch entry zone is often difficult. Herein, the authors report that cone-beam computed tomography (CBCT) can assist accurate microcatheter tip placement at the shunted pouch entry zone before staring embolization. This is the novel application of intraoperative CBCT to treat anterior condylar AVF successfully treated with precise and selective TVE.

Validation experiment of a numerically processed millimeter-wave interferometer in a laboratory

We propose a new interferometer system for density profile measurements. This system produces multiple measurement chords by a leaky-wave antenna driven by multiple frequency inputs. The proposed system was validated in laboratory evaluation experiments. We confirmed that the interferometer generates a clear image of a Teflon plate as well as the phase shift corresponding to the plate thickness. In another experiment, we confirmed that quasi-optical mirrors can produce multiple measurement chords; however, the finite spot size of the probe beam degrades the sharpness of the resulting image.

Sialyl-lewis-x antigen immunoreaction of colorectal-cancer and its relationship to hematogenous metastasis

The adhesion of cancer cells to endothelial cells of the target organ is one of the most important steps of hematogenous metastasis. Especially, sialyl Le(X) plays an important role in defining the metastasis. The expression of sialyl Le(X) antigen in colorectal cancer and its usefulness not only as an indicator of metastatic potential but also as a prognostic factor was studied immunohistochemically. Fifty-five (32.4%) sialyl Le(X) antigen-positive tumors were found in 170 colorectal cancers. There was a significant correlation between the expression of sialyl Le(X) antigen and the histological tumor type, venous invasion, lymph node metastasis, as well as liver metastasis. Hematogenous metastases were significantly more frequent in patients with sialyl Le(X)-positive tumor than in those with sialyl Le(X)-negative tumor; and prognosis was significantly poorer in the former. The results suggest that sialyl Le(X) antigen plays a role in hematogenous metastasis of colorectal cancer, and that the expression of sialyl Le(X) is associated with poor prognosis.

Inhibition of liver metastasis formation by anti-CD44 variant exon 9 monoclonal antibody

The overexpression of variants of the glycoprotein CD44 is thought to be associated with the tumorigenesis and progression of human cancers. We examined the role of the variant CD44v8-10 in the metastasis of the human colon cancer cell line HT29 using a monoclonal antibody (mAb 44-1V) reactive with the v9 product. After immunization with mAb 44-1V, the growth of HT29m cells in vitro was not retarded. Six-to 8-week-old mice were divided into 4 groups for liver metastasis assay. All animals in control groups injected with intrasplenic HT29m developed metastases. In contrast, only one of the animals injected with HT29m that reacted with mAb 44-1V developed a metastatic tumor in the liver. The intravenous administration of mAb 44-1V after intrasplenic HT29m injection did not inhibit the formation of liver metastasis. In addition, the adhesiveness of the HT29m cells to the basement membrane matrix was decreased by treatment with the anti-CD44v9 mAb. These findings indicated that a CD44 variant containing the products of variants of exons v8-10 may play an important role in adhesion of tumor cells to the capillaries of distant organs in the metastatic process.

Cytokine profile during the clinical course of toxic shock syndrome

Toxic shock syndrome (TSS) is an acute febrile disease with multiple organ involvement caused by massive and rapid release of cytokines induced by staphylococcal exotoxins. However, the precise cytokine profile is still undefined in clinical cases. We measured serum cytokine concentrations in a patient who developed TSS after a caesarean section. Measurements were taken on admission and several times during the course of the disease. Methicillin-resistant Staphylococcus aureus producing TSS toxin-1 and staphylococcal enterotoxin C was detected in the lochia and venous blood. Serum interleukin (IL)-6 level was markedly increased on admission, and IL-10, tumour necrosis factor-alpha, and interferon-gamma levels were also raised. These cytokine levels rapidly returned to normal levels. In contrast, IL-1beta and IL-2 were below the analytical sensitivity threshold throughout the course. Our data and other previous case reports indicate that a marked increase in IL-6 concentration could be a clinical marker of TSS onset.

Comparison between in vivo and in vitro pharmacokinetics of succinylcholine in humans

PURPOSE

To compare the in vivo and in vitro pharmacokinetics of succinylcholine (SCh) in humans.

METHODS

A bolus of SCh 1 mg.kg(-1) (n = 7) or 2 mg.kg(-1) (n = 11) was given to 18 patients anesthetized with thiopental. Arterial blood samples for determination of in vivo SCh concentrations were collected every 30 s for 5 min. Another 20-ml blood sample was obtained before induction of anesthesia for determination of in vitro SCh. Concentrations of SCh were measured by high-performance liquid chromatography. In vivo and in vitro concentrations of SCh vs time data were analyzed by the one-compartment model.

RESULTS

The respective in vivo and in vitro pharmacokinetic parameters (SCh 1 mg.kg(-1) vs SCh 2 mg.kg(-1)) were as follows: Plasma clearance was 4.17 +/- 2.37 and 1.85 +/- 0.28 l.min(-1), P < 0.05, vs 2.91 +/- 2.01 and 1.27 +/- 0.43 l.min(-1), P < 0.05. Elimination half-life was 25.4 +/- 10.6 and 47.4 +/- 5.4 s, P < 0.002 vs 26.3 +/- 10.0 and 75.2 +/- 21.8 s, P < 0.00005.

CONCLUSION

These results suggest that the rapid disappearance of SCh from the circulation is due to diffusion out of the blood vessels rather than to enzymatic hydrolysis.

Comparison between tube compensation and pressure support ventilation techniques on respiratory mechanics

In the intubated patient, the presence of an endotracheal tube increases the work of breathing during spontaneous breathing. The tube compensation technique was developed as a new ventilator mode that can compensate for that additional the work of breathing. We investigated the respiratory parameters during the pressure support ventilation 0, 5, 10 cmH2O and tube compensation 100% modes of the Puritan Bennett 840 ventilator in ten postoperative patients who had undergone radical surgery for oesophageal cancer. Measurements were performed just before extubation. The tidal volume, respiratory rate and other respiratory parameters were measured with a Ventrak respiratory monitor, and the duty ratio, mean inspiratory flow, and rapid shallow breathing index were calculated. In particular, we performed a comparison between pressure support ventilation 5 cmH2O and tube compensation 100%, because pressure support ventilation 5 cmH2O is the usual ventilating mode before the extubation in our intensive care unit. The tidal volume of pressure support ventilation 10 cmH2O was significantly larger and the respiratory rate was significantly lower than the other three modes. There was no significant difference in the minute volume, tidal volume, and respiratory rate between pressure support ventilation 5 cmH2O and tube compensation 100%. The duty ratio of pressure support ventilation 10 cmH2O was significantly smaller than the other three modes. There was no significant difference in the duty ratio and rapid shallow breathing index between pressure support ventilation 5 cmH2O and tube compensation 100%. It was concluded that the assist levels of pressure support ventilation 5 cmH2O and tube compensation 100% were almost equal for clinical purposes.

Evaluation of tube compensation in the Bennett 840 ventilator--a new ventilatory mode to support spontaneous breathing

Respiratory care patients frequently require intubation with an endotracheal tube (ETT). Unfortunately, the ETT introduces a pressure drop (deltaPETT) that depends on the respiratory flow rate, thus increasing the work of breathing (WOB). Pressure support ventilation (PSV) cannot adequately compensate for this added WOB, because the degree of inspiratory assistance by PSV is fixed. Therefore, a technique called tube compensation (TC) has been developed to address deltaPETT. We examined the performance of TC and compared it with PSV of 5 cm H2O. The experimental system was constructed from a simulator, a test-lung, flow sensors, and a Bennett 840, and the respiratory parameters were studied. ETTs with IDs 6.5 and 8.0 mm were used. The quadratic approximation obtained for deltaPETT in the 6.5-mm ETT was 2.316 x flow + 7.910 x flow2, while that for the 8.0-mm ETT was 1.881 x flow + 3.353 x flow2. The maximum inspiratory flow (MIF) increased significantly with increasing TC, but tidal volume and inspiratory time did not show marked changes. The MIF for TC of 100% was larger than that for PSV of 5 cm H2O, when the 6.5-mm ID was used, but there was no significant difference between these modes when an ID of 8.0 mm was used. For both the 6.5 and 8.0-mm IDs, the PV loop corresponding to 100% TC was larger than that for PSV of 5 cm H2O. TC only compensated for the WOB caused by the ETT, whereas PSV compensated for the WOB caused by the ETT and the demand valve system. In clinical use, the differences between TC and PSV will demand attention.

Granulocyte colony-stimulating factor (G-CSF)-mediated signaling regulates type IV collagenase activity in head and neck cancer cells

Granulocyte colony-stimulating factor (G-CSF), a hematopoietic cytokine, regulates the proliferation and differentiation of granulocytic progenitor cells and functionally activated mature neutrophils. G-CSF also affects nonhematopoietic tumor cells through its binding to the specific receptor (G-CSFR) on the cells. The type IV collagenase [matrix metalloproteinase 2 (MMP-2)] is known to play a main role in the process of invasion and metastasis, but its regulation, for example, in expression or in activation, is not clearly understood. In this study, we investigated the role of G-CSF in the regulation of tumor cell invasion and the synthesis of MMP-2. G-CSFs producing the head and neck carcinoma cell line T3M-1 cells with metastatic ability and no G-CSF receptor (G-CSFR) expression were transfected with G-CSFR expression vector. In vitro treatment of G-CSFR-transfectant T3M-1 cells with recombinant G-CSF (rG-CSF) significantly augmented their invasive potential in a reconstituted basement membrane (Matrigel) system compared with that of parental cells. Moreover, MMP-2 activity of G-CSFR-transfectant T3M-1 cells was enhanced by the stimulation with rG-CSF, as assessed by gelatin zymography. These results identify G-CSF as a regulator of MMP-2 and cellular invasion.

Highly selective one-pot synthesis of spirophosphoranes exhibiting reversed apicophilicity by oxidation of dianions generated from P-H spirophosphorane

[see reaction]. Mild and highly selective one-pot procedures for obtaining phosphoranes that exhibit reversed (O-cis) apicophilicity are described. On the basis of the procedures, O-cis phosphorane bearing an aryl group (R = 2,4,6-tri-i-propylphenyl) could be isolated for the first time; the procedure is also applicable for alkyl derivatives. Particularly effective was the use of I2 as an oxidizing reagent.

The effects of organ resection on rat urinary bladder carcinogenesis

The effect of unilateral nephrectomy, orchiectomy or partial hepatectomy on the growth of chemically induced rat bladder tumors was investigated. Male F344 rats were treated with 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) for 5 weeks, and surgical resection of one of these organs was performed 2 weeks after the completion of BBN administration. Histological evaluation of the bladder 24 weeks after the start of the experiment revealed that unilateral nephrectomy and orchiectomy significantly increased the numbers of preneoplastic and neoplastic lesions as compared with the corresponding sham-operated groups. Partial hepatectomy also enhanced tumor growth, although not significantly. Immunohistochemical studies examining the effect of organ resection on normal bladder urothelium showed that BrdU immunostaining of urothelial cells significantly increased 7 days after unilateral nephrectomy or orchiectomy, while BrdU incorporation was minimum after partial hepatectomy or sham operation. C-met expression in the bladder urothelium was evident following unilateral nephrectomy or partial hepatectomy, while increased immunoreactivity of androgen receptor was noted following unilateral orchiectomy. Further study is needed to determine the exact mechanism of the bladder tumor growth-enhancing effect associated with organ restriction.

Differences in respiratory parameters during continuous positive airway pressure and pressure support ventilation in infants and children

The extubation criteria of pressure support ventilation (PSV) in infants and children were not yet established. We studied the differences in respiratory parameters during continuous positive airway pressure (CPAP) using a constant flow type ventilator and PSV using a demand valve type ventilator. Nineteen children (1.9+/-2.9 years old) who were ready to extubate were studied. All patients had recovered from their respiratory failure and had finished the weaning process of the ventilatory support. They were scheduled for extubation on the next day when their ventilatory mode had attained to a PSV of 3 cmH2O with a positive end-expiratory pressure (PEEP) of 3 cmH2O. On the extubation day, tidal volume (TV) and respiratory frequency (RR) were measured with a respiratory monitor at two modes (CPAP of 3 cmH2O and PSV), and the duty ratio (DR) and mean inspiratory flow (MF) were calculated. The sequence of the ventilatory mode was random. No case required reintubation. TV was 61.6+/-54.9 during CPAP and 67.7+/-61.4 ml during PSV, and RR was 38.5+/-10.6 and 37.1+/-8.8 beats/min., respectively. DR was 0.382+/-0.067 and 0.359+/-0.085, and MF was 96.6+/-78.3 and 101.0+/-69.0 ml/sec., respectively. The measured parameters and calculated values showed no significant difference between CPAP and PSV. It was found that the respiratory parameters were almost the same with CPAP and PSV immediately before the extubation, and the previous extubation criteria of CPAP can be used.

Hyperbaric oxygen therapy given 30 minutes after spinal cord ischemia attenuates selective motor neuron death in rabbits

OBJECTIVE

Spinal cord ischemia sometimes causes paraplegia because the spinal motor neuron cells are vulnerable to ischemia. Although various protective remedies for spinal cord injury have been reported, there have been few established clinical methods. Although hyperbaric oxygen (HBO) has been used clinically as a treatment for ischemia, the reason for its effectiveness is still uncertain because sufficient experimental data are lacking.

DESIGN

Prospective, randomized, controlled study.

SETTING

Experimental animal research laboratory in a university research center.

SUBJECTS

Twenty-three Japanese white rabbits, weighing 2-3 kg.

INTERVENTIONS

A modified rabbit spinal cord ischemia model of infrarenal aortic occlusion for 15 mins was employed. Rabbits were randomly assigned to four groups; the rabbits in group A did not undergo ischemic insults (n = 5). The rabbits in groups B and C underwent ischemic insult for 15 mins, followed by 1 hr of HBO treatment at 3 atm absolute with 100% oxygen at 30 mins (n = 6) or 6 hrs (n = 7) after reperfusion, respectively. The rabbits in group D underwent ischemic insult for 15 mins without HBO treatment (n = 5).

MEASUREMENTS AND MAIN RESULTS

We observed neurologic functions for 14 days. The sections of the spinal cords were stained with hematoxylin and eosin, and the number of spinal motor neurons in ventral region was counted by light microscopy. All rabbits in groups A and B could stand, whereas all rabbits in groups C and D showed irreversible paraplegia on days 2 and 14 after reperfusion. Spinal motor neurons in ventral gray matter in groups C and D decreased significantly compared with those in groups A and B.

CONCLUSIONS

HBO therapy shortly after ischemic insult had protective effects against ischemic spinal cord damage. However, delayed treatment with HBO did not change the prognosis.

Changes in expression of mRNAs in the gerbil hippocampus following transient forebrain ischemia

The phenomenon of delayed neuronal death in CA1 neurons following brief duration of global ischemia has eluded definitive explanation. Using a differential display technique, we examined changes in expression of mRNAs in the hippocampus following 5-min cerebral ischemia in Mongolian gerbils. Under pentobarbital anesthesia, gerbils were sacrificed by decapitation at 6 h (n = 20) and 2 days (n = 20) after ischemia, and sham-operated gerbils (n = 20) were sacrificed at 6 h after surgery. Total RNA was isolated from the hippocampal samples in each group for the differential display analysis. The mRNAs were classified into three patterns; gradual disappearance, decrease and recovery, and new appearance. Representative mRNAs in three patterns were subcloned and sequenced partly. An mRNA in the gradual disappearance pattern showed homologous with neuronal pentraxin. In situ hybridization and Northern blot analyses of neuronal pentraxin revealed the gradual disappearance pattern. An mRNA in the decrease and recovery pattern showed homologous with 14-3-3 protein gamma-subtype, and an mRNA in the new appearance pattern showed no homology in the data base. The differential display analysis is a useful technique with which to investigate changes in expression of mRNAs following transient cerebral ischemia. The novel mRNA may be involved in the treatment of cerebral ischemia. Further studies are necessary for this point.

Leukotoxin, 9,10-epoxy-12-octadecenoate, causes pulmonary vasodilation by stimulation of vascular eNOS and iNOS

We have previously reported that leukotoxin, 9,10-epoxy-12-octadecenoate (Lx) dilates rat pulmonary arteries by means of nitric oxide synthase (NOS) activation. In this study, we investigated if Lx stimulates constitutive and/or inducible NOS. We studied the effect of the NOS inhibitors, N(G)-monomethyl-L-arginine and aminoguanidine, as well as endothelium denudation on Lx-induced rat pulmonary arterial dilation and that of aminoguanidine on Lx-induced endothelium denuded lipopolysaccharide (LPS)-treated rat pulmonary arterial dilation and tissue cGMP content. Furthermore, we assessed the effect of aminoguanidine, an inducible NOS (iNOS) inhibitor, on the cGMP content increase induced by Lx in LPS-treated human pulmonary artery smooth muscle cells (HPASMC). The NOS inhibitors and endothelium denudation significantly attenuated Lx-induced vasodilation. Aminoguanidine also significantly attenuated Lx-induced vasodilation in LPS-treated rat denuded pulmonary arteries, and attenuated Lx-induced cGMP content increase in denuded pulmonary arterial rings from LPS-treated rats and in LPS-treated HPASMC. These results suggest that Lx causes pulmonary vasodilation by stimulation of vascular endothelial NOS (eNOS) and iNOS.

Effect of Ca(2+)-independent mechanisms on the hypoxic relaxation of guinea-pig tracheal rings

Hypoxia induces bronchodilation in vivo and in vitro, but the mechanisms are still unclear. To evaluate whether an extra- or intracellular free Ca(2+) ion is involved in the mechanisms of hypoxic relaxation, we simultaneously measured cytosolic Ca(2+)levels and tensions in both intact and denuded guinea-pig tracheal strips precontracted with histamine (100 microM), and assessed the effect of hypoxia on guinea-pig tracheal rings precontracted with okadaic acid (10 microM) and calyculin-A (0.1 approximately 10 microM) under an extracellular Ca(2+)-free state. The exposure of tracheal rings to hypoxia induced an immediate decrease of tracheal tension without decrease in intracellular free Ca(2+)levels. In the presence of okadaic acid but not calyculin-A, hypoxic air exposure caused significant transient reductions in tracheal tone. Further, thapsigargin (5 microM or 10 microM) did not affect hypoxic bronchodilation, suggesting that the release of intracellular Ca(2+) does not take a role in hypoxic bronchodilation. Hypoxic dilation decreased ATP content in epithelium-intact rings but not epithelium-denuded rings, indicating a relationship between hypoxic dilation and change of adenine nucleotide in epithelium-intact rings. Our findings indicate that the epithelium dependent mechanisms of hypoxic relaxation of guinea pig tracheal rings preconstricted with histamine may not be related to the mobilization of extra and intra-cellular Ca(2+).

Selective uptake by cancer cells of liposomes coated with polysaccharides bearing 1-aminolactose

We investigated the selective uptake of liposomes chemically modified by polysaccharides-cholesterol derivatives with 1-aminolactose (lactose) in two human hepatoma cell lines (HUH7 and Alexander), a human colon cancer cell line (FCC) and a human lung cancer cell line (KNS). The uptakes of the labeled liposomes alone (conventional liposomes), those with cholesterol pullulan (CHP) and with lactose (lactose CHP) were compared in four cancer cells and normal rat hepatocytes after 3 hours of incubation. The radioactivities of the lactose CHP were 4.4, 4, 3.4 and 4.4 times greater than those of CHP in HuH7, Alexander, FCC and KNS cells, respectively, after 3 hours of incubation. All the above differences were statistically significant (p < 0.01). No statistically significant differences were seen in the case of hepatocytes. Thus, cancer cells have a common affinity with lactose CHP liposomes, however, these mechanisms appear to have no connection with the galactose-specific asialoglycoprotein receptors of hepatocytes.

Enantiomer-selective activation of racemic catalysts

Asymmetric catalysts can be evolved into highly activated catalysts by association with chiral activators. This asymmetric activation process is particularly useful in racemic catalysis through selective activation of one enantiomer of the racemic catalysts. Recently, a strategy whereby a racemic catalyst is selectively deactivated by a chiral additive has been reported to yield nonracemic products. However, we have reported a strategy that is an alternative to asymmetric catalysts but is conceptually opposite, in which a chiral activator selectively activates rather than deactivates one enantiomer of a racemic chiral catalyst. The advantage of this activation strategy over the deactivation counterpart is that the activated catalyst can produce a greater enantiomeric excess (x(act)% ee) in the products than the ee attained by the enantiomerically pure catalyst on its own. Therefore, 'asymmetric activation' could provide a general and powerful strategy for the use of not only atropisomeric and, hence, racemic ligands but also chirally flexible and 'pro-atropisomeric' ligands without enantiomeric resolution!

Comparison of non-tryptophan fluorophores in protein-free extract of brunescent and non-brunescent human cataract

PURPOSE

To investigate whether any of the fluorophores in the human lens nuclei might be responsible for human brunescent cataract formation.

METHODS

Human lens nuclei (non-brunescent, from 13; brunescent, from 8) were obtained after extracapsular cataract extraction in nondiabetic patients. Protein-free extract, prepared by filtrating the water-soluble fraction of each nucleus through a centrifugal ultrafilter (molecular weight < 5,000), was analytically separated by high-performance liquid chromatography.

RESULTS

No significant differences between non-brunescent and brunescent nuclei were observed in the concentrations (mean +/- SD) of 3-hydroxykynurenine O-beta-glucoside (0.67 +/- 0.38 vs. 0.85 +/- 0. 62 micromol/g wet weight), 4-(2-amino-3-hydroxyphenyl)-4-oxobutanoic acid O-glucoside (4.1 x 10(5) +/- 2.9 x 10(5) vs. 6.3 x 10(5) +/- 5. 0 x 10(5) area unit/g wet weight), and kynurenine (0.016 +/- 0.011 vs. 0.029 +/- 0.021 micromol/g wet weight). A novel fluorophore that has not been identified so far was significantly present more in brunescent than in non-brunescent nuclei (brunescent: 1.5 x 10(5) +/- 1.0 x 10(5) vs. non-brunescent: 2.6 x 10(3) +/- 6.3 x 10(3) area unit/g wet weight, P <.01). Digestion of the protein-free extract with beta-glucosidase eliminated the peak corresponding to the novel unidentified fluorophore.

CONCLUSION

The present results imply a novel protein-unbound fluorophore, presumably a beta-glucoside, might possibly be involved in brunescent cataract formation.

P-ANCA-positive Wegener's granulomatosis presenting with hypertrophic pachymeningitis and multiple cranial neuropathies: case report and review of literature

An autopsy case of hypertrophic pachymeningitis and multiple cranial neuropathies is reported. A 53-year-old woman with paraplegia and various neurological signs which developed over a 2 year period was diagnosed as having an epidural mass with thickened dura mater extending from the lower cervical to the thoracic spinal cord. In addition, bilateral episcleritis, blephaloptosis, and blindness of the right eye with various cranial nerve deficits were found to be caused by the mass lesions involving the paranasal sinuses, orbit, and the cavernous sinus. Perinuclear antineutrophil cytoplasmic antibody (p-ANCA) was positive, but cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) was negative by enzyme-linked immunosorbent assay. The partially removed epidural mass with hypertrophied dura mater and biopsy of the paranasal lesions showed chronic granulomatous inflammation with vasculitis. The remaining lesions resolved with steroid therapy with remarkable neurological improvement. The positive p-ANCA test, paranasal involvement, the report of a similar histopathological case and a review of the literature on granulomatous pachymeningitis suggest the presence of p-ANCA-positive Wegener's granulomatosis with central nervous system involvement characterized by hypertrophic pachymeningitis and/or multiple cranial neuropathies.

Syntheses, structures, and reactivities of mono- and dinuclear iridium thiolato complexes containing nitrosyl ligands

Reactions of the iridium(III) nitrosyl complex [Ir(NO)Cl2(PPh3)2] (1) with hydrosulfide and arenethiolate anions afforded the square-pyramidal iridium(III) complex [Ir(NO)(SH)2(PPh3)2] (2) with a bent nitrosyl ligand and a series of the square-planar iridium(I) complexes [Ir(NO)(SAr)2(PPh3)] (3a, Ar = C6H2Me3-2,4,6 (Mes); 3b, Ar = C6H3Me2-2,6 (Xy); 3c, Ar = C6H2Pri3-2,4,6) containing a linear nitrosyl ligand, respectively. Complex 1 also reacted with alkanethiolate anions or alkanethiols to give the thiolato-bridged diiridium complexes [Ir(NO)(mu-SPri)(SPri)(PPh3)]2 (4) and [Ir(NO)(mu-SBut)(PPh3)]2 (5). Complex 4 contains two square-pyramidal iridium(III) centers with a bent nitrosyl ligand, whereas 5 contains two tetrahedral iridium(0) centers with a linear nitrosyl ligand and has an Ir-Ir bond. Upon treatment with benzoyl chloride, 3a and 3b were converted into the (diaryl disulfide)- and thiolato-bridged dichlorodiiridium(III) complexes [[IrCl(mu-SC6HnMe4-nCH2)(PPh3)]2(mu-ArSSAr)] (6a, Ar = Mes, n = 2; 6b, Ar = Xy, n = 3) accompanied by a loss of the nitrosyl ligands and cleavage of a C-H bond in an ortho methyl group of the thiolato ligands. Similar treatment of 4 gave the dichlorodiiridium complex [Ir(NO)(PPh3)(mu-SPri)3IrCl2(PPh3)] (7), which has an octahedral dichloroiridium(III) center and a distorted trigonal-bipyramidal Ir(I) atom with a linear nitrosyl ligand. The detailed structures of 3a, 4, 5, 6a, and 7 have been determined by X-ray crystallography.

[Anesthetic management of a patient with hemophilia A for left modified Blalock-Taussig shunt]

We gave anesthesia to a patient with hemophilia A for left modified Blalock-Taussig shunt. The patient was a twenty five-day-old boy with pulmonary atresia. We performed the bolus injection test of factor VIII concentrate in preoperative period. His factor VIII activity increased from 9.3 to 113.3% after a bolus injection of 165 units. To keep his factor VIII activity above 80% in perioperative period, a bolus of 125 units of recombinant factor VIII concentrate was injected at anesthesia induction, 125 units 2 hours after the start of the operation, and 125 units 6 hours after the end of the operation. Factor VIII activity 2 hours after anesthesia induction increased only 37.8%, and we had to infuse recombinant factor VIII concentrate additionally. We measured factor VIII activity during operation, and he finally received total of 415 units of factor VIII concentrate. Hydroxyethyl starch infusion, blood transfusion and bleeding in the perioperative period might have caused the factor VIII activity to decrease beyond our expectation. We should infuse factor VIII concentrate properly measuring the factor VIII activity during this operation.

[Evaluation of left ventricular diastolic function during coronary artery bypass grafting by color M-mode Doppler echocardiography]

The objective of the present study was to evaluate the effects of the coronary artery bypass graft surgery (CABG) and cardioplegic arrest on left ventricular diastolic function. Ten patients with coronary artery disease were studied by transesophageal Doppler echocardiography. Doppler measurements included peak velocity during early filling (peak E velocity), peak velocity during atrial contraction (peak A velocity), and the ratio of peak E velocity to peak A velocity (E/A). The rate of propagation of peak early filling flow velocity (FPV) was also measured using color M-mode Doppler echocardiography. Hemodynamic and Doppler-derived variables were measured before and after sternotomy, after the end of cardiopulmonary bypass (CPB) and after closure of the sternum. E/A showed a significant decrease after sternotomy and did not return to the pre CPB level. FPV increased after CPB. FPV was correlated with E/A (r = 0.54, P = 0.013 pre-CPB; r = 0.54, P = 0.014 post-CPB). E/A showed a significant correlation with heart rate. After the influence of heart rate had been eliminated by the analysis of covariance, corrected E/A value showed a significant increase post-CPB compared to that in pre-CPB (0.68 +/- 0.29 to 1.10 +/- 0.29, P < 0.05). In conclusion, FPV and heart-rate-corrected E/A increased after CPB. This suggests improvement of diastolic function during CABG.

Apoptosis-promoting gene (bax) transfer potentiates sensitivity of squamous cell carcinoma to cisplatin in vitro and in vivo

Modulation of apoptosis may potentiate the sensitivity of tumor cells to chemotherapeutic agents, thus improving the clinical outcome of cancer treatment. Bax, an apoptosis-promoting member of the bcl-2 family, may be a key factor influencing the chemosensitivity of tumor cells, however, its involvement in cellular sensitivity to anti-cancer drugs remains uncertain in squamous cell carcinoma (SCC). To investigate the role of bax gene expression in modulating cisplatin (CDDP)-induced apoptosis in vitro, an established CDDP-resistant human head and neck SCC (IMC-3 cell line) was transfected with bax gene-bearing mammalian expression vector. Overexpression of the bax gene in CDDP-resistant IMC-3 cells elevated the CDDP susceptibility of tumor cells to a level similar to that of the parental IMC-3 cells. In an in vivo study, percutaneous transfer of apoptosis-promoting bax gene by particle-mediated (gene gun) delivery caused overexpression of Bax in SCC, which was confirmed by immunohistochemical staining, and inhibited the growth of mouse CDDP-resistant SCC. Furthermore, combination therapy with bax gene transfer and subcutaneous administration of CDDP at 3-day intervals markedly inhibited the growth of mouse SCC. Thus, overexpression of bax in SCC by a gene gun system appears to be a rational approach to improving the efficacy of chemotherapy and treatment outcome. We suggest that exogenous bax expression may have therapeutic applications for enhancing chemotherapy in SCC.

Changes in messenger ribonucleic acid species in gerbil brain perturbation

The differential display technique was applied to observe the molecular dynamism of messenger ribonucleic acid (mRNA) in this study. Using this technique, the changes in mRNAs in brain perturbation such as ischemia was observed to understand the molecular base of the reaction. The transient cerebral ischemia was induced by clipping both common carotid arteries for 5 minutes in Mongolian gerbils. The total RNA was extracted from the hippocampal tissue samples before ischemia, 6 hours and 2 days after ischemia. The mRNAs were reverse transcribed and subsequently amplified by polymerase chain reaction (PCR). PCR products were displayed by autoradiography as ladders on a denaturing polyacrylamide gel. According to the autoradiography, mRNAs were divided into three patterns: 1) mRNAs obtained from the control decreased at 6 hours after 5-minute ischemia and disappeared at 2 days completely; 2) decreased mRNAs at 6 hours after ischemia recovered at 2 days; and 3) new mRNAs appeared after cerebral ischemia. Located bands of interest on a gel were cut out and reamplification of complementary deoxyribonucleic acid was performed. The pGEM-T Vector System was used for subcloning of the amplified PCR products. The differential display technique is the powerful method for detecting genes that are unique to ischemic processes and reactions.

Glutathione depletion induces giant DNA and high-molecular-weight DNA fragmentation associated with apoptosis through lipid peroxidation and protein kinase C activation in C6 glioma cells

Glutathione (GSH) depletion caused by l-buthionine-(S,R)-sulfoximine (BSO) induced apoptosis that was recognized by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick endo-labeling (TUNEL), nuclear DNA staining with fluorescence dye, and internucleosomal DNA fragmentation in C6 rat glioma cells. The BSO-induced cell death was associated with caspase-3 activation. Lipid peroxidation and protein kinase C (PK-C) activation were observed during the apoptosis of C6 cells, and these events were inhibited by antioxidants and iron chelators without affecting BSO-induced GSH depletion. Furthermore, approximately 2 Mbp giant DNA fragments were observed in the BSO-treated cells. The giant DNA fragmentation were followed by approximately 30-700 kbp and then less than 100 kbp, including internucleosomal DNA fragmentations. Such serial DNA degradation was prevented by the antioxidants, the iron chelators, and the PK-C inhibitors. These results suggest that during apoptosis induced by GSH-depletion caused by BSO, reactive oxygen species endogenously produced cause lipid peroxidation and that the lipid peroxidation induced PK-C activation, processes which are thought to be involved in the giant DNA, high-molecular-weight DNA, and the internucleosomal DNA fragmentations.

The activation of nitric oxide synthase by copper ion is mediated by intracellular Ca2+ mobilization in human pulmonary arterial endothelial cells

The aim of the study was to elucidate the vasodilatory mechanism due to Cu2+ by assessing nitric oxide (NO) production as determined by NOx (NO, NO2-, and NO3-) that is released from human pulmonary arterial endothelial cell (HPAEC) monolayers using a NO chemiluminescence analyzer, and also to assess Ca2+ movement using 45Ca and fura 2 in HPAEC. Cu2+ (10(-6)-10(-4) M) significantly increased NO production in a dose-dependent manner when extracellular Ca2+ was present. 45Ca influx into the adherent cells was dose-dependently enhanced by Cu(2+) (10(-6)-10(-4) M), but not by Mn(2+), Zn(2+) or Fe(2+). [Ca2+]i, measured by monitoring the fluorescence changes of fura 2, was significantly elevated in the presence of Cu2+. The increase in [Ca2+]i induced by Cu2+ was inhibited by either diethyldithiocarbamate (DDC) or the depletion of extracellular Ca2+. The dihydropyridine receptor agonist, BayK8644, significantly attenuated the Cu2+-induced increase in [Ca2+]i in a dose dependent manner and nitrendipine or nifedipine, the dihydropyridine receptor antagonists, dose-dependently inhibited a Cu2+-induced increase in [Ca2+]i. These results suggest that Cu2+ activates eNOS through the mechanism of [Ca2+]i elevation due to Ca2+ influx into HPAEC and that the Cu2+-induced [Ca2+]i elevation in HPAEC is likely due to activation of the dihydropyridine-like receptors.

Expression of c-MET/HGF receptor mRNA and protein in human non-malignant and malignant prostate tissues

We previously reported the expression of hepatocyte growth factor (HGF), a ligand for c-MET, at the level of mRNA and protein in human prostate tissues. The present study was carried out to evaluate the relationship between c-MET expression and cancer cell proliferation or effect of cancer therapy. The expression both in mRNA and protein levels of c-MET proto-oncogene was determined semi-quantitatively by reverse transcription-competitive polymerase chain reaction (RT-competitive PCR) and Western blot analysis for prostate tissues from 32 Japanese male subjects. In addition, tissue localization of c-MET translation product was examined by immunohistochemistry for corresponding specimens. Although there was significantly higher c-MET protein expression in malignant (prostate cancer treated with/without neoadjuvant endocrine therapy) than in non-malignant prostate tissues (normal prostate and benign prostate hyperplasia; BPH), unexpectedly, c-MET mRNA showed high expression in the non-malignant group. Thus, there was no parallelism between mRNA and protein expressions of c-MET. Endocrine therapy did not alter c-MET mRNA and protein expressions in human prostate cancer. Immunohistochemical localization and expression of c-MET protein was found to be intense in cancer cells and weak in epithelia of normal and hyperplastic prostates. Unconcerted expression of mRNA and protein of c-MET, the reason of which is uninterpretable, is supposed to be one of characteristics of human prostate cancer.

Dexamethasone modulates the expression of endothelin-1 and -A receptors in A7r5 vascular smooth muscle cells

Endothelin-1 (ET-1) is synthesized and released by vascular smooth-muscle cells (VSMCs). Glucocorticoids induce the release of ET-1 from VSMCs into the medium. We investigated whether glucocorticoids modulate ET-1 action by an autocrine production of ET-1 in A7r5 VSMCs. Dexamethasone (100 nM) stimulated the release of ET-1 into the medium. Treatment with 100 nM dexamethasone for 24 h reduced the peak increase of intracellular free Ca2+ induced by ET-1 (100 nM) by 50%, an effect that was dose-dependently inhibited by the specific ET(A)-receptor antagonist FR139317. Scatchard plots of [125I]-ET-1 binding revealed that dexamethasone reduced the number of maximal ET-1 binding sites without altering their binding affinity. FR139317 reversed the decrease in ET-1 binding capacity induced by dexamethasone. Northern blot analysis revealed that dexamethasone increased the level of prepro-ET-1 messenger RNA (mRNA) and decreased the level of ET(A)-receptor mRNA. FR139317 prevented the decrease in the level of ET(A)-receptor mRNA induced by dexamethasone. Results indicate that dexamethasone downregulates ET(A) receptors in A7r5 VSMCs at the mRNA level, in part by the autocrine production of ET-1.

Effect of surfactant on respiratory failure associated with thoracic aneurysm surgery

OBJECTIVE

To study the effects of surfactant administration on the left lung after surgical repair of descending aortic aneurysms on postoperative respiratory failure.

DESIGN

Randomized, prospective, controlled study.

SETTING

Clinical investigation.

PATIENTS

Eleven patients with respiratory failure associated with thoracic aneurysm surgery.

INTERVENTION

Eleven adult patients with acute respiratory failure (PaO2/FIO2 <300 torr [<40 kPa]) after surgical repair of descending aortic aneurysms. The artificial surfactant (30 mg/kg) was given to the operated side of the lung by intrabronchial instillation in six patients (surfactant group), whereas nothing was instilled in the other five patients (control group).

MEASUREMENTS AND MAIN RESULTS

Hemodynamic parameters, blood gas, and peak inspiratory pressure were measured at the end of surgery, before surfactant instillation, and at 2, 6, 12, 24, and 48 hrs after surfactant instillation. At the end of surgery, the mean +/- SEM values of the PaO2/FIO2 ratio were 204 +/- 25 torr (27.2 +/- 3.3 kPa) in the surfactant group and 240 +/- 26 torr (32.0 +/- 3.5 kPa) in the control group. After 2, 6, 12, and 48 hrs, improvements in the PaO2/FIO2 ratios were observed in the surfactant group, whereas the control group showed no improvement. Two hours after surfactant instillation, the mean value in the PaO2/FIO2 ratio was significantly higher in the surfactant group (318 +/- 24 torr [42.4 +/- 3.2 kPa]) (p < .05) compared with the control group values (240 +/- 34 torr [32 +/- 4.5 kPa]).

CONCLUSION

Surfactant administration immediately after surgery restored gas exchange in postoperative respiratory failure associated with thoracic aneurysm surgery.

Efficacious diagnosis of primary and metastatic human carcinomas with a combination of p53 mutation analysis and clonality analysis of androgen receptor gene

It is occasionally difficult to differentiate between multiple primary and metastatic tumors in case of multiple carcinomas. p53 gene mutation pattern by PCR-SSCP and a clonality analysis on the human androgen receptor gene (HUMARA) in multiple tumors were used to distinguish whether carcinomas were multiple primary tumors or a metastasis. Three female patients with multiple carcinomas, who had undergone surgical resection, were selected for these analyses as typical candidates from 11 cases tested. In the first case with bilateral breast cancer the combined analyses were performed on DNA extracted from tumor portions in paraffin sections of each tumor sample and the results indicated that the carcinomas consisted of a primary carcinoma and metastatic tumors. The carcinomas in the second patient consisted of multiple primary carcinomas and the tumors in the third patient consisted of two independent primary carcinomas with different clonal origins. Thus a combination of p53 gene mutation analysis and clonality analysis on HUMARA provided useful, reliable evidence which can help in discriminating multiple primary tumors from metastatic tumors.

Clinical significance of combined immunohistochemical detection of CD44v and sialyl LeX expression for colorectal cancer patients undergoing curative resection

To evaluate their prognostic value, the expressions of CD44v and sialyl LeX (SLX) in colorectal cancers were studied immunohistochemically. Tissue specimens were reacted with monoclonal antibodies (mAb) CD44-1V and CSLEX-1. Of the 145 colorectal cancer patients undergoing curative resection, 59 (40.7%) were positive for mAb CD44-1V, and 40 (27.6%) were positive for mAb CSLEX-1. There was a significant correlation between the combined expression of SLX and CD44v8-10 and lymph node metastasis. The patients with tumors negative for CD44v8-10 and SLX had the most favorable prognoses. Conversely, the patients with tumors positive for both CD44v8-10 and SLX had a high recurrence rate and the poorest prognoses. In a multivariate analysis using the Cox regression model, the combined expression of SLX and CD44v8-10 emerged as an independent prognostic indicator. These results suggested that the combined expression of CD44v8-10 and SLX may be a biologic marker of prognostic significance.

Leukotoxin (9, 10-epoxy-12-octadecenoate) impairs energy and redox state of isolated perfused rat lung

We investigated the perturbation of energy balance and redox state in leukotoxin (9, 10-epoxy-12octadecenoate) (Lx)- and endothelin-1 (ET-1)-induced lung injury, using isolated perfused rat lungs. To examine any relationship between these parameters, intracellular levels of adenine nucleotides, pyridine coenzymes and glutathione were determined by reversed-phase high-performance liquid chromatography (HPLC) in the freeze-dried tissues of isolated rat lungs. The tissue samples were perfused with a physiological salt solution containing either Lx only, Lx plus NG-monomethyl-L-arginine (L-NMMA), Lx plus NG-monomethyl-D-arginine (D-NMMA), Lx plus superoxide dismutase (SOD) or ET-1 only. In isolated perfused lung tissue, 10 mol of Lx caused permeability-increased lung injury, and 10 nM of ET-1, which caused a comparable increase in wet lung weight, evoked pulmonary capillary hypertensive lung injury. Lx-injured lungs showed decreases in the contents of ATP, NADPH, NADH, reduced glutathione (GSH), (2ATP + ADP)/2(ATP + ADP + AMP) ratio (energy charge) and NADH/NAD+ ratio, and increased the contents of ADP and AMP compared with the vehicle control and ET-1-injured lungs. Such effects of Lx were significantly attenuated by pretreatment with 0.4 mM L-NMMA or 500 units/ml of SOD, but not with 0.4 mM D-NMMA. On the other hand, the ET-1-injured lung evidenced decreased tissue GSH. These findings indicate that Lx shifted the lung redox state toward oxidation and that Lx-induced lung injury was involved in the imbalance of the energy and redox state via production of nitric oxide and/or superoxide anion.