Effects of changes in the physical properties of the central elastic artery on haemodynamic characteristics during ageing

The change in blood pressure during the ageing process depends on the changes in the physical properties of the arterial system. The conventional method of studying ageing, i.e. observing a focus group of people, requires long periods of time and also makes it difficult to separate the ageing effect from the effects of complex geriatric diseases. Therefore, a computer simulation was used to analyse how physical property changes in the central elastic artery during the ageing process affect the blood pressure and input impedance of the blood vessels. An increase in the arterial stiffness and an increase in the wall thickness increased the systolic pressure and the pulse pressure. An increase in the lumen diameter decreased the mean pressure. The pulse wave velocity and shape were changed in the central elastic artery group but were not changed outside this group. Also, the input impedance at a low frequency was increased in the central elastic artery group but was not changed outside this group. In this study, the way in which changes in specific physical properties of the artery affect the haemodynamic characteristics during ageing was analysed.

Intraoperative Endoleak During EVAR: Frequency, Nature, and Significance

Objective: Endoleaks are critical complications of endovascular abdominal aortic aneurysm repair (EVAR). This study sought to determine the frequency and nature of intraoperative endoleaks and their impact on postoperative endoleak-related events. Methods: A retrospective chart review was performed of all patients who underwent EVAR at our institution. The impact of intraoperative endoleaks on postoperative endoleak rates and endoleak-related reintervention rates were assessed. Results: From December 18, 1996, to May 21, 2003, 241 patients underwent EVAR. An endoleak was observed during 126 (52.3%) procedures. Type I endoleaks were observed in 63 (26.1%) cases: 35 proximal and 31 distal endoleaks (3 cases at both attachments). Angioplasty, additional cuff placement, or stenting corrected 59 (89.4%) of these endoleaks. A total of 71 type II intraoperative endoleaks (29.5%) and 8 type IV endoleaks (3.3%) were observed without any attempted corrective maneuvers. Ten type III endoleaks (4.2%) occurred but all resolved with angioplasty or additional cuff placement. In all, 86 (35.7%) endoleaks persisted on completion angiogram. Patients with a type I or type II intraoperative endoleak were more likely to have an endoleak at 1.5 years (31.4% vs. 21.6%, P = .018). Reinterventions were required more often after an intraoperative type I endoleak (10% vs. 4%, P = .003). Patients with intraoperative endoleaks demonstrated a trend toward less postoperative aneurysm diameter reduction at 2 years (43.8% vs. 74.5%, P = .104). Conclusion: The presence of a type I or a type II endoleak during EVAR significantly increases the likelihood of a postoperative endoleak and should prompt a high degree of suspicion during follow-up.

l-Ascorbic acid 2-phosphate promotes elongation of hair shafts via the secretion of insulin-like growth factor-1 from dermal papilla cells through phosphatidylinositol 3-kinase

BACKGROUND

l-Ascorbic acid 2-phosphate (Asc 2-P), a derivative of l-ascorbic acid, promotes elongation of hair shafts in cultured human hair follicles and induces hair growth in mice.

OBJECTIVES

To investigate whether the promotion of hair growth by Asc 2-P is mediated by insulin-like growth factor-1 (IGF-1) and, if so, to investigate the mechanism of the Asc 2-P-induced IGF-1 expression.

METHODS

Dermal papilla (DP) cells were cultured and IGF-1 level was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay after Asc 2-P treatment in the absence or presence of LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor. Also, hair shaft elongation in cultured human scalp hair follicles and proliferation of cocultured keratinocytes were examined after Asc 2-P treatment in the absence or presence of neutralizing antibody against IGF-1. In addition, keratinocyte proliferation in cultured hair follicles after Asc 2-P treatment in the absence or presence of LY294002 was examined by Ki-67 immunostaining.

RESULTS

IGF-1 mRNA in DP cells was upregulated and IGF-1 protein in the conditioned medium of DP cells was significantly increased after treatment with Asc 2-P. Immunohistochemical staining showed that IGF-1 staining is increased in the DP of cultured human hair follicles by Asc 2-P. The neutralizing antibody against IGF-1 significantly suppressed the Asc 2-P-mediated elongation of hair shafts in hair follicle organ culture and significantly attenuated Asc 2-P-induced growth of cocultured keratinocytes. LY294002 significantly attenuated Asc 2-P-inducible IGF-1 expression and proliferation of follicular keratinocytes in cultured hair follicles.

CONCLUSIONS

These data show that Asc 2-P-inducible IGF-1 from DP cells promotes proliferation of follicular keratinocytes and stimulates hair follicle growth in vitro via PI3K.

The cuff leak test is not predictive of successful extubation

In intubated patients the presence of a cuff leak (CL) is used as a predictor of successful extubation. CL is proposed to indicate laryngeal edema and predict which patients may develop complications such as postextubation stridor and eventual reintubation. Our objective was to evaluate the reliability of CL in our population of critically ill trauma patients. A retrospective chart review was performed of patients admitted to the trauma service who required mechanical ventilation. All patients undergo the CL test by a single respiratory therapist team before attempted extubation. Data collected included body mass index (BMI), endotracheal tube (ETT) size, length of time of mechanical ventilation, tidal volumes (Vt), and the size of the patient's trachea based on CT scan. The test is performed by the respiratory therapists and involves measuring expired Vt before and after the ETT cuff has been deflated and listening for an audible leak. A positive test result is defined as a CL greater than 10 per cent of Vt or, when volumes are not available, as audible air expired. From October 2005 to May 2006, 150 mechanically ventilated patients were identified and 49 charts were available for review. Forty-one patients had a cuff leak (+CL), whereas eight did not (-CL). The two cohorts were similar in age (+CL = 36.5 years, -CL = 38.1 years, P = 0.82), male gender (+CL = 70%, -CL = 50%, P = 0.25) ETT size (+CL = 7.4, -CL = 7.4, P = 0.57), and BMI (+CL = 28 kg/m2, -CL = 27 kg/m2, P = 0.71). The average tracheal diameter (+CL = 17.4 mm, -CL = 17.5 mm, P = 0.90) as well as the ratio of ETT and tracheal diameter was similar for the two cohorts (+CL = 0.65, -CL = 0.64, P = 0.73). Four patients (10%) in the +CL cohort failed extubation, whereas none of the -CL cohort failed (0%) (P = 0.40). The CL test does not reliably identify those patients who will require reintubation in our trauma population. In addition, the ratio of ETT and tracheal diameter is not predictive of successful extubation.

The effect of bupivacaine.HCl on the physical properties of neuronal membranes

Fluorescent probe techniques were used to evaluate the effect of bupivacaine.HCl on the physical properties (transbilayer asymmetric lateral and rotational mobilities, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMVs) isolated from bovine cerebral cortex. An experimental procedure was used based on selective quenching of both 1,3-di(1-pyrenyl)propane (Py-3-Py) and 1,6-diphenyl-1,3,5-hexatriene (DPH) by trinitrophenyl groups, and radiationless energy transfer (RET) from the tryptophans of membrane proteins to Py-3-Py. Bupivacaine.HCl increased the bulk lateral and rotational mobilities, and annular lipid fluidity in SPMVs lipid bilayers, and had a greater fluidizing effect on the inner monolayer than that of the outer monolayer. The magnitude of increasing effect on annular lipid fluidity in SPMVs lipid bilayer induced by bupivacaine.HCl was significantly far greater than magnitude of increasing effect of the drug on the lateral and rotational mobilities of bulk SPMVs lipid bilayer. It also caused membrane proteins to cluster. These effects of bupivacaine.HCl on neuronal membranes may be responsible for some, though not all, of the local anesthetic actions of bupivacaine.HCl.

Coil Knotting during Endovascular Coil Embolization for Ruptured MCA Aneurysm. A Case Report

SUMMARY

Complications during coil embolization of cerebral aneurysms include thromboembolic events, hemorrhagic complications related to procedural aneurysmal rupture and parent vessel perforation, and coil-related complications. The present report describes a rare coil-related complication involving spontaneous coil knotting.

Safety and immunogenicity of a vaccine targeting human papillomavirus types 6, 11, 16 and 18: a randomized, placebo-controlled trial in 176 Korean subjects

Human papillomavirus (HPV) is a major causative agent of anogenital warts and a necessary cause of cervical cancer. This report will serve to assess the safety and immunogenicity of quadrivalent (types 6, 11, 16, and 18) HPV L1 virus-like particle (VLP) vaccine in the Korean population. We performed a randomized, double-blind, placebo-controlled study in 176 volunteers aged 9-23 years. Using a 2:1 ratio for randomization, 117 women were assigned to quadrivalent HPV (20 mug type 6, 40 mug type 11, 40 mug type 16, and 20 mug type 18) vaccine and 59 women to placebo. Individuals received vaccine at day 1, month 2, and month 6 and provided blood samples for analysis at enrollment at month 7. Analyses were done as specified in the study protocol. Quadrivalent HPV vaccine was generally well tolerated, with no vaccine-related serious adverse experiences. Quadrivalent HPV vaccine induced seroconversion for each vaccine-related HPV type. At month 7, vaccine-induced type-specific antibody titer was high. In conclusion, administration of quadrivalent HPV VLP vaccine to Korean women aged 9-23 years was generally well tolerated and highly immunogenic.

Dihydroartemisinin enhances radiosensitivity of human glioma cells in vitro

PURPOSE

The antimalarial agent, artemisinin, also confers cancer-specific cytotoxic effects by reacting with ferrous iron atoms to form free radicals. Here, we investigated the radiosensitizing effects of dihydroartemisinin on glioma cells and assessed some possible mechanisms for these effects.

MATERIALS AND METHODS

U373MG glioma cells treated with various concentrations of dihydroartemisinin plus radiation, and efficiency of radiosensitization was assessed by clonogenic survival assay. Expression and activity of antioxidant enzymes, glutathione-S-transferase (GST) were quantified by western blot and enzymatic activity analyses, respectively.

RESULTS

Dihydroartemisinin showed higher cytotoxicity in the glioma cell lines than in the liver, breast or cervical cancer cell lines. In clonogenic survival assays, treatment with dihydroartemisinin alone dose-dependently reduced the number of U373MG colonies, while treatment with dihydroartemisinin plus gamma-irradiation showed far lower clonal survival than cultures treated with radiation or dihydroartemisinin alone. The radiosensitizing effect of dihydroartemisinin was blocked significantly by the free radical scavengers, NAC and TIRON, indicating association with dihydroartemisinin-induced ROS generation. In addition, the radiation-induced expression of endogenous GST was suppressed by treatment with dihydroartemisinin. The radiosensitizing effect of dihydroartemisinin was also markedly enhanced by the addition of holotransferrin

CONCLUSION

Taken together, our results strongly suggest that dihydroartemisinin triggers production of ROS and inhibits GST activity, leading to effective and therapeutically relevant radiosensitization of human glioma cells.

Glovax's perspective: opportunities and approaches to vaccine business in Asia

Glovax Co., Ltd. has focused on regional population needs, and assessed potentially interesting vaccine candidates for their safety, efficacy and cost-effectiveness. Economic analysis was made to identify the area of high commercial potential based on quantity demands and pricing flexibility. Epidemiological data on the target diseases were reviewed so that we could identify the vaccines of more limited interests worldwide but still of high significance in regional public health. Several viral vaccine products were selected as our priority including Japanese encephalitis and Hepatitis A vaccines. Extensive safety and clinical studies have been projected. To ensure that a safe and effective vaccine be supplied at the same quality level, new manufacturing facilities are being constructed in our region. Several approaches have been made to overcome technical, financial, and managerial obstacles. Close partnerships with industry, biomedical community and regulatory agencies may enhance the viability of our approach to be a successful vaccine player in this region.

Chronic hepatitis: in vivo proton MR spectroscopic evaluation of the liver and correlation with histopathologic findings

PURPOSE

To correlate the in vivo hydrogen 1 ((1)H) magnetic resonance (MR) spectroscopic features of the chronic hepatitis-involved liver with the histopathologic stages of fibrosis.

MATERIALS AND METHODS

Seventy-five patients with chronic hepatitis were examined with (1)H MR spectroscopy, which was performed in the right hepatic lobe. The peak areas of glutamine and glutamate complex (Glx), phosphomonoesters (PME), glycogen and glucose complex (Glyu), and lipid were measured on the liver spectra. The histopathologic features were correlated with the in vivo (1)H MR spectroscopic findings at each stage of chronic hepatitis. Fifteen healthy volunteers also were included as a control group.

RESULTS

(1)H MR spectroscopy depicted Glx, PME, Glyu, and lipid in all livers. In the normal livers, the calculated mean (+/- SD) relative metabolite-to-lipid ratios of Glx, PME, and Glyu were 0.14 +/- 0.04, 0.03 +/- 0.01, and 0.21 +/- 0.04, respectively. The mean value of each metabolite-to-lipid ratio was significantly different between all stages of chronic hepatitis, and with the exception of the mean ratio at the interval between stages 0 and 1 (P > .05), the mean value increased significantly with increasing stage (P < .05). A pronounced peak was demonstrated at 3.9-4.1 ppm at (1)H MR spectroscopy of all stages of chronic hepatitis except stage 0.

CONCLUSION

The increased Glx, PME, and Glyu levels relative to the lipid content with chronic hepatitis indicated the severity of fibrosis and thus were concordant with the histopathologic stages. In vivo (1)H MR spectroscopy might be a substitute for liver biopsy in the diagnosis and staging of chronic hepatitis.

Characterization of inwardly rectifying K(+) conductance across the basolateral membrane of rat tracheal epithelia

The rat primary cultured-airway monolayer has been an excellent model for deciphering the ion channel after nystatin permeabilization of its basolateral or apical membrane. Inwardly rectifying K(+) currents were characterized across the basolateral membrane in symmetrical HCO(-)(3)-free high K(+) Ringer's solution (125 mM) in this study. The potency of K(+) channel inhibitors against K(+) conductance was Ba(2+) (IC(50) = 5 microM) > Cs(+) (IC(50) = 2 mM) >> glybenclamide (IC(50) > 5 mM) >> TEA (IC(50) >> 100 mM). The application of basolateral Cs(+) changed K(+) conductance into an oscillating current, and its frequency (holding voltage = -100 mV) increased with increase in concentration of basolateral Cs(+) (0.05-5 mM) and in degree of hyperpolarization. Addition of basolateral Cs(+) blocked inward current strongly at -100 mV and hardly at all at -60 mV, giving a sharp curvature to the I-V relation of the IRK current. RT-PCR, Western blotting, and immunohistochemical analyses showed that Kir2.1 might be present in basolateral membrane of tracheal epithelia and plasma membrane of pulmonary alveolar cells.

Hepatocellular carcinoma with lung metastasis in a 9-year-old-boy

Hepatocellular carcinoma (HCC) remains chemoresistant and, therefore, the principal treatment of HCC is surgical resection. After a 9-year-old boy with huge HCC with lung metastasis received the 5 cycles of chemotherapy (cisplatin and Adriamycin), the lung metastasis had been resolved completely and the size of HCC in liver had decreased. Right hepatic trisegmentectomy was performed, and then the additional 3 cycles of chemotherapy was given. Currently, the patient shows no recurrence of HCC 42 months after surgical extirpation.

Efficacy of single-dose SA 14-14-2 vaccine against Japanese encephalitis: a case control study

BACKGROUND

In China, since 1989, an estimated 120 million children have been immunised with the SA 14-14-2 live-attenuated Japanese encephalitis (JE) vaccine at ages 1, 2, and 6 years. A case-control study of licensed vaccine found two doses to be 98% effective. Subsequently, researchers found that single-dose vaccine efficacy was high; we aimed to confirm this result.

METHODS

During July 11-24, 1999, 160000 doses of JE vaccine were given to children aged 1-15 years, resident in three districts of Nepal. Several cases of JE were admitted to hospital from early August. We obtained names and addresses of cases with serological evidence of a recent infection from Bheri Zonal Hospital, Nepalgunj. We did a matched case-control study and calculated the odds ratio of vaccination among JE cases and age-sex matched village controls.

FINDINGS

20 children, aged 1-15 years, were identified whose illness conformed with the JE case definition and were resident in villages receiving the vaccine. None of 20 JE cases had received JE vaccine compared with 326 of 557 age-sex matched village controls. The efficacy of a single dose of JE vaccine was 99.3% (CI 94.9-100%).

INTERPRETATION

A single dose of JE vaccine is highly efficacious in preventing Japanese encephalitis when administered only days or weeks before exposure to infection.

Radical excision of pediatric craniopharyngioma: recurrence pattern and prognostic factors

The purpose of our study was to investigate the pattern of recurrence and the prognostic factors for recurrence of pediatric craniopharyngiomas after radical excision. A series of 36 patients with craniopharyngiomas (21 boys and 15 girls; age range 1-15 years; mean 7.3 years) were reviewed. All patients had undergone radical excision without radiotherapy. The mean follow-up period was 52 months (range 1-149 months). Tumors recurred in 14 patients within 83 months (mean 31.4 months). The overall 5-year recurrence-free survival rate was 55%. Regular neuroimaging follow-up detected tumor recurrence while the lesions were still small before symptoms developed (P<0.05). At the first surgical procedure, the optic nerve/chiasm (n=23) was the most common adhesion site. The most frequent sites of recurrence were the optic nerve/chiasm (n=6) and the pituitary fossa (n=6). Tumor location was the single significant clinical predictor of recurrence. The 5-year recurrence-free survival rate was 39% for those who had an intrasellar tumor component and 81% for those who did not (P<0.05). The Ki-67 labeling indices (LIs) of primary tumors did not have prognostic value for recurrence. Recurrent tumors tended to have higher Ki-67 LIs than their primary counterparts. On the basis of this study, we concluded that craniopharyngiomas with intrasellar components should be followed cautiously and the necessity for regular follow-up should be emphasized, even when the tumor is "totally" resected.

Three-dimensional object recognition by use of a photorefractive volume holographic processor

We present a photorefractive volume holographic processor for recognition of three-dimensional (3D) objects. The templates are recorded by use of a volume hologram in a photorefractive LiNbO(3):Fe crystal located at the Fresnel diffraction region and correlated in real time with a 3D object illuminated by coherent light. Experimental results for recognition of 3D objects are presented and discussed. To the best of our knowledge, this is the first time a photorefractive volume holographic technique for 3D object recognition has been reported.

Studies on the interfacial characterization of O/W emulsion for the optimization of its treatment

Wastewater produced in the form of an o/w emulsion is difficult to treat properly because of its complex behavior. To acquire information for the optimization of emulsion controlling processes, the interfacial features of emulsion systems have been investigated in this work. The surface tension is found to decrease as the oil content is increased, and contact angle is influenced by the hydrophobicity of the substrate. The work of adhesion for substrates with different degrees of hydrophobicity has been estimated from the contact angle and surface tension. Temperature and pH have a significant influence on the turbidity and surface tension, and it is observed that electrophoretic characteristics of oil droplets are closely related with turbidity. Also, effects of inorganic salts and surfactants on the electrokinetic properties of emulsions have been considered, and the influence of coagulant on the stability is discussed through the calculation of potential energy of interaction between oil droplets. Adsorption and electrocoagulation processes have been attempted under various conditions in order to examine the practical treatment efficiencies of emulsion in relation to its interfacial characteristics.

Involvement of oxidative stress in ascorbate-induced proapoptotic death of PC12 cells

Ascorbate is a reducing agent, but it is also known to oxidize cellular components under specific conditions. The mechanism of this oxidative action, however, is not well established. Ascorbate treatment increased lipid peroxide content in PC12 cells, but did not increase quantities of lipid peroxide when homogenates of PC12 cells were treated with ascorbate, suggesting that cellular integrity is required for ascorbate to generate lipid peroxidation. However, dehydroascorbate increased lipid peroxide production in both intact PC12 cells and the cell homogenates. These differential effects of ascorbate and dehydroascorbate on intact cells versus homogenates suggest that the dehydroascorbate in cytosol induces an oxidative stress. Ascorbate in culture medium is rapidly oxidized to dehydroascorbate, which is transported into cells by a glucose transporter (GLUT). The GLUT antagonists wortmannin and cytochalasin B, or a high concentration of glucose, blocked (14)C uptake (from ascorbate) in a time-dependent manner and suppressed lipid peroxide production in PC12 cells. These observations support the concept that ascorbate is oxidized to dehydroascorbate, which is transported into cells via GLUT. The dehydroascorbate induces oxidative stress. The oxidative stress triggered apoptosis according to ceramide production, caspase-3 activation, and TUNEL. We have concluded that ascorbate is taken up after oxidation to dehydroascorbate via a "dehydroascorbate transporter" (GLUT), and the dehydroascorbate generates an oxidative stress which triggers apoptosis. These studies have significant implications for conditions under which a high concentration of ascorbate in a tissue is released during a period of hypoxia (e.g., stroke) and taken up during a reperfusion period as dehydroascorbate. Inhibiting uptake of dehydroascorbate may offer novel therapeutic strategies to alleviate brain damage during a reperfusion period.

Restriction fragment length dimorphism-PCR method for the detection of extended-spectrum beta-lactamases unrelated to TEM- and SHV-types

The diagnostic ability of the restriction fragment length dimorphism-polymerase chain reaction (RFLD-PCR) method was evaluated. Seven primer pairs, newly designed from 44 beta-lactamase genes encoding extended-spectrum beta-lactamases not related to TEM- and SHV-types, were used to differentiate OXA-2, FOX-3, CMY-3, IMP-1, and IMI-1 beta-lactamases. The RFLD-PCR was carried out successfully, and these genes were differentiated by the sizes of their PCR products and by the difference in restriction fragment length when each amplicon was digested with a unique restriction enzyme. This discriminatory detection of the genes was confirmed by sequencing the PCR products.

A case of hemorrhagic gallbladder paraganglioma causing acute cholecystitis

Gallbladder paraganglioma is a very rare tumor and so far only a few cases have been reported. Most of these were asymptomatic and were found incidentally during operation. Recently, we experienced a gallbladder paraganglioma that gave rise to hemorrhage, which in turn caused acute cholecystitis. Our case involved a 45 year-old female patient complaining of an intermittent right upper abdominal pain. After a preoperative evaluation, cholecystectomy and lymphadenectomy were performed under the impression of gallbladder cancer with acute cholecystitis. Postoperative pathologic examination revealed a hemorrhagic gallbladder paraganglioma accompanied by acute cholecystitis. Immunohistochemical staining of the chief cells for neuron specific enolase, chromogranin and synaptophysin were positive. Sustentacular cells also stained positively for S100 protein.