Differentiation of bacteria cell wall using Raman scattering enhanced by nanoparticle array.

We have fabricated surface-enhanced Raman scattering (SERS) substrates based on arrays of silver nanoparticles grown on porous anodic alumina templates. Using this nanotechnology platform, label-free and high-speed detection of bacteria are achieved. SERS spectra of various bacteria including Staphylococcus Aureus (Gram-positive bacterium), Klebsiella Pneumoniae (Gram-negative bacterium), and Mycobacterium Smegmatis (Mycobacterium) were recorded. The highly reproducible SERS-based technological platform is capable of differentiating different kinds of bacteria by PCA, LDA, clustering analysis, and SVM methods, which provides promising opportunity for biosensing of clinical microbes.

Contact behavior of focused ion beam deposited Pt on p-type Si nanowires.

Pt contact on p-Si nanowires (NWs) using Ga-ion-induced deposition by a focused ion beam was formed with a specific contact resistance (rho(c)) of 1.54 x 10(-6) Omega cm(2). Ohmic behavior is caused by Ga-ion-induced amorphization of Si NWs underneath the Pt contact. A very low Schottky barrier height associated with interface states raised from Pt-amorphized Si junction and with an image force induced by the applied bias can be implemented to elucidate ultralow rho(c). The value of rho(c) lower than that of any known contact to Si NWs demonstrates a practical method for integrating NWs in devices and circuits.

Electrical and optoelectronic characterization of a ZnO nanowire contacted by focused-ion-beam-deposited Pt.

We report on the transport properties of a single ZnO nanowire (NW) measured as a function of the length/square of the radius ratio via the transmission line method (TLM). The specific contact resistance of FIB-Pt contacts to the ZnO NWs is determined to be as low as 1.1 x 10(-5) Omega cm(2). The resistivity of the ZnO NWs is measured to be 2.2 x 10(-2) Omega cm. ZnO NW-based UV photodetectors contacted by FIB-Pt with a photoconductive gain as high as approximately 10(8) have been fabricated and characterized.

Neoadjuvant docetaxel followed by adjuvant doxorubicin and cyclophosphamide in patients with stage III breast cancer.

BACKGROUND: To evaluate clinical and pathologic response to neoadjuvant docetaxel therapy in patients with stage III breast cancer. PATIENTS AND METHODS: Forty-five patients were planned to receive four cycles of docetaxel 100 mg/m2 every 3 weeks, followed by surgery, four cycles of doxorubicin 60 mg/m2 and cyclophosphamide 600 mg/m2 (AC) every 3 weeks, radiation therapy (RT), and tamoxifen when indicated. RESULTS: After four cycles of neoadjuvant docetaxel, the clinical response rate within the breast was 59% (95% CI 42% to 73%) and overall (breast and axilla) was 49% (95% CI 38% to 72%) in the intention-to-treat (ITT) population. At the time of surgery, 10% (n=4) of patients had a pathologic complete response (pCR) in the breast, 27% (n=11) had a pCR within the axillary lymph nodes, and 7% (n=3) had a pCR in the breast and axilla (95% CI 2% to 21%). An additional 5% (n=2) had minimal residual invasive tumor (<5 mm). The 5-year overall survival rate was 80%. The percentage of patients with grade 3/4 neutropenia was similar during docetaxel (93%) and AC (86%), while a greater percentage of patients had febrile neutropenia during docetaxel treatment (27%) compared with AC treatment (7%). CONCLUSIONS: Neoadjuvant docetaxel followed by surgery, adjuvant AC, hormonal therapy where indicated, and RT is an active regimen for patients with stage III breast cancer.

Elastic modulus of resin-based dental restorative materials: a microindentation approach.

This research aimed to determine the elastic modulus of resin-based dental composite restoratives using the microindentation test method. Results were then compared with those obtained with the ISO three-point bending test method. Five materials from the same manufacturer (3M ESPE) were selected for the study. They included microfill (A110), minifill (Z100 and Filtek Z250), poly-acid modified (F2000), and flowable (Filtek Flowable [FF]) composites. The indentation moduli of the composites were determined using a custom-designed microindentation test set up after conditioning in water at 37 degrees C for 1 week and 1 month. The indentation test was carried out at peak load of 10 N and Oliver & Pharr's method was used to determine the maximum projected contact area. Data was analyzed using ANOVA/post-hoc Scheffe's test at significance level 0.05 and Pearson's correlation at significance level 0.01. The mean indentation modulus ranged from 5.80 to 15.64 GPa and 5.71 to 15.35 GPa at 1 week and 1 month, respectively. At both time periods, the indentation modulus of Z100 was significantly higher than all other materials. F2000 was significantly higher than Z250, which was significantly stiffer than A110 and FF. The rankings were in good agreement with the ISO flexural test. A significant, positive, and strong correlation (r = 0.93 and 0.94 at 1 week and 1 month, respectively) in modulus between ISO three-point bending and microindentation test methods was observed. In view of the small specimen size and good reproducibility, the microindentation reflects a potential test method for determining the elastic properties of dental composite restoratives.

Effects of aging on mechanical properties of composite restoratives: a depth-sensing microindentation approach.

This study investigated the effects of aging on the hardness and modulus of two composites (Tetric Ceram [TC], Vivadent; Esthet X [EX], Dentsply), a conventional (Compoglass [CG], Vivadent) and a posterior compomer (Dyract Posterior [DP], Dentsply) using a depth-sensing microindentation approach. Seven specimens (3-mm wide x 3-mm long x 2-mm deep) of each material were made and conditioned in distilled water at 37 degrees C. Hardness and modulus of the materials were determined at seven and 30 days using depth-sensing microindentation testing with the Instron MicroTester. Hardness was determined by dividing the peak load over the maximum projected contact area while effective modulus was calculated by analysis of the loading/unloading P-h curves and the analytical model according to Oliver and Pharr (1992). Results were analyzed using one-way ANOVA/Scheffe's post-hoc test and Independent Samples t-test at significance level 0.05. Mean Vickers Hardness (HV) ranged from 46.60 to 58.67 and 44.44 to 59.41 at seven and 30 days, respectively. Mean indentation modulus ranged from 9.57 to 9.95 and 9.19 to 10.03 for the same time periods. At both time periods, EX was significantly harder than all the other materials and HV values for TC were significantly greater than CG. No significant difference in hardness and modulus was observed between seven and 30 days for all materials with the exception of CG. For the latter, a significant decrease in mechanical properties was detected over time.

Fracture resistance of compomer and composite restoratives.

This study evaluated and compared the fracture toughness of compomers and composites. Three compomer (Compoglass F [CG], Vivadent; F2000 [FT], 3M-ESPE; Dyract Posterior [DP], Dentsply) and three composite (Tetric Ceram [TC], Vivadent; Z250 [ZT], 3M-ESPE; Esthet X [EX], Dentsply) restoratives were selected for the study. Single-edged notched specimens (25 x 2 x 2 mm) were fabricated according to manufacturers' instructions and conditioned in distilled water at 37 degrees C for one week prior to testing. Seven specimens were made for each material. The specimens were loaded to failure using an Instron microtester with a crosshead speed of 0.5 mm/minute. Data were subjected to ANOVA/Scheffe's test and Independent Samples T-test at significance level 0.05. The mean fracture toughness (K(IC)) ranged from 0.97 to 1.23 MPam 1/2 for compomers and 1.75 to 1.92 MPam 1/2 for composites. The fracture toughness of compomers was significantly lower than their composite counterparts. No significant difference in K(IC) values was observed among the different composites. When the compomers were compared, FT had significantly higher fracture toughness than DP and CG. In view of their poorer resistance to crack propagation, compomers are not recommended for use in stress-bearing areas.

Effect of food-simulating liquids on the shear punch strength of composite and polyacid-modified composite restoratives.

This study evaluated the effects of food-simulating liquids on the shear punch strength of two composites (Tetric Ceram [TC], Vivadent; Esthet X [EX], Dentsply), a conventional (Compoglass [CG], Vivadent) and a posterior polyacid-modified (Dyract Posterior [DP], Dentsply) composite. Thirty-two specimens (10-mm in diameter and 1.6-mm thick) of each material were made, randomly divided into four groups of eight and conditioned for one week as follows--Group 1 (control): air at 37 degrees C; Group 2: distilled water at 37 degrees C; Group 3: 75% ethanol-water solution at 37 degrees C and Group 4: heptane at 37 degrees C. After conditioning, the specimens were restrained within the test apparatus and subjected to shear punch strength testing using a 3.2 mm diameter punch at a crosshead speed of 0.5 mm/minute. The shear punch strength of the specimens was computed and the data was subjected to ANOVA/Scheffe's tests at significance level 0.05. The effect of food-simulating liquids on shear strength was found to be material dependent. All materials with the exception of EX were significantly weakened by ethanol solution. For DP, a significant increase in strength was observed after conditioning in water. EX was significantly stronger than TC and DY after conditioning in air, water and ethanol solution. The shear punch strength of EX and CG was significantly higher than DY after conditioning in heptane.

Bone response to unloaded titanium implants in the fibula, iliac crest, and scapula: an animal study in the Yorkshire pig.

The reconstruction of extended maxillary and mandibular defects with prefabricated free flaps is a two stage procedure, that allows immediate function with implant supported dentures. The appropriate delay between prefabrication and reconstruction depends on the interfacial strength of the bone-implant surface. The purpose of this animal study was to evaluate the removal torque of unloaded titanium implants in the fibula, the scapula and the iliac crest. Ninety implants with a sandblasted and acid-etched (SLA) surface were tested after healing periods of 3, 6, and 12 weeks, respectively. Removal torque values (RTV) were collected using a computerized counterclockwise torque driver. The bicortical anchored 8mm implants in the fibula revealed values of 63.73 Ncm, 91.50 Ncm, and 101.83 Ncm at 3, 6, and 12 weeks, respectively. The monocortical anchorage in the iliac crest showed values of 71.40 Ncm, 63.14 Ncm, and 61.59 Ncm with 12 mm implants at the corresponding times. The monocortical anchorage in the scapula demonstrated mean RTV of 62.28 Ncm, 97.63 Ncm, and 99.7 Ncm with 12 mm implants at 3, 6, and 12 weeks, respectively. The study showed an increase of removal torque with increasing healing time. The interfacial strength for bicortical anchored 8mm implants in the fibula was comparable to monocortical anchored 12 mm implants in the iliac crest and the scapula at the corresponding times. The resistance to shear seemed to be determined by the type of anchorage (monocortical vs. bicortical) and the length of the implant with greater amount of bone-implant interface.

Multi-axial spine biomechanical testing system with speckle displacement instrumentation.

This paper reports on the design and development of a multi-axis (up to 6 axes) mechanical tester for spinal research and testing. The developed spine tester allowed true motion to be simulated on a specimen in pure or combined modes. To demonstrate the capability of the new tester flexural stiffness properties of sheep lumbar motion segments were evaluated together wiith a non-contact speckle displacement measurement system. The flexural stiffness of the specimens was measured and compared under constrained and non-constrained testing conditions; with relieving of shear forces (non-constrained), it was found that the specimen behaved in a 'stiffer' manner.

The potency (ED50) and cardiovascular effects of rapacuronium (Org 9487) during narcotic-nitrous oxide-propofol anesthesia in neonates, infants, and children.

UNLABELLED: We studied the neuromuscular blocking effects of rapacuronium (Org 9487) (dose-response curve, onset, and 50% effective dose [ED50] value), and changes in heart rate and blood pressure, as well as evidence of histamine release in neonates, infants, and children in an open-label, randomized, two-center study. Fifteen neonates, 30 infants, and 30 children were studied. Anesthesia was induced and maintained with propofol, nitrous oxide:oxygen (60:40), and fentanyl. Mechanomyographic monitoring of neuromuscular function was performed at the thumb. The potency (ED50) for neonates, infants, and children were 0.32 (95% confidence interval [CI] 0.15-0.61), 0.28 (95% CI 0.11-0.61), and 0.39 (95% CI 0.17-0.85) mg/kg, respectively. Neonates who received 0.3, 0.6, or 0.9 mg/kg Org 9487 developed a maximum T1 twitch depression of 34 +/-28%, 98 +/- 3%, and 99 +/- 2%, respectively. Time-to-peak effect (onset time) for 0.9 mg/kg Org 9487 was 57 +/- 20 s. Maximum percent T1 twitch depression (+/-SD) in infants who received 0.3, 0.6, or 0.9 mg/kg rapacuronium was 41 +/- 34%, 96 +/- 7%, and 100 +/- 1%, respectively. Time-to-peak effect for 0.9 mg/kg Org 9487 was 62 +/- 29 s. In children 0.3, 0.6, and 0.9 mg/kg rapacuronium resulted in an average percent T1 twitch suppression of 29 +/- 23, 83 +/- 11, and 90 +/- 16, respectively. Time-to-peak effect of 0.9 mg/kg Org 9487 was 96 +/- 33 s, respectively. There was no evidence of histamine release or significant changes in heart rate or blood pressure in either group at any dose. Rapacuronium is a low-potency nondepolarizing muscle relaxant with a fast onset of relaxation and minimal cardiovascular effects. Its potency (ED50) is similar in neonates (0.32 mg/kg), infants (0.28 mg/kg), and children (0.39 mg/kg). T1 suppression (90% +/- 16) is less and time to peak effect (96 +/- 33 s) is greater (0.9 mg/kg rapacuronium) in children, compared with the combined group of infants and neonates. IMPLICATIONS: This study assesses the potency of rapacuronium (Org 9487) in pediatric patients. The potency of rapacuronium is similar in neonates (0.32 mg/kg), infants (0.28 mg/kg), and children (0.39 mg/kg).

Internal iliac artery aneurysmo-rectal fistula associated with multiple aortoiliac aneurysms.

Fistular communication between an internal iliac artery aneurysm and rectum presenting as massive lower gastrointestinal tract bleeding is a rare entity in clinical practice. Prompt diagnosis and experienced therapeutic application determine the outcome. Herein we report the successful management of such a complication. A 68-year-old male had multiple aneurysms over the abdominal aorta and bilateral iliac arteries. It was the largest aneurysm arising from the right internal iliac artery which ruptured into the rectum and resulted in massive hematochezia. After extraanatomical bypass with right axillo-femoral and femoro-femoral crossover grafts to restore the circulation to the bilateral lower limbs, the infrarenal abdominal aorta just immediately above the proximal aneurysm was transected and closed as a blind stump. All the aneurysms were included in this resection and as much of the infected aneurysm tissue was debrided as possible. The rectum was exteriorized using Hartmann's procedure. The patient survived the operation and was discharged in good condition.

Cardiac perforation and tamponade induced by external cardiac massage: a case report.

A 76-year-old woman suffered from sudden loss of consciousness while sitting in a chair. She was sent to a local hospital and found to be in shock. After a brief period of external cardiac massage, she was transferred to our hospital. In our emergency department she was lethargic with cool, clammy extremities. Her blood pressure dropped from 113/53 mmHg on arrival to 72/42 mmHg 2 hours later. Echocardiography showed massive pericardial effusion, fair left ventricular contractility and no abnormal segmental motion. The echocardiographic appearance suggested fibrin-like substance in the pericardial space, which was felt to indicate the presence of blood. Enhanced chest computerized tomography showed extravasation of contrast medium from the right ventricular outflow tract. At surgery, a small perforation was found at the infundibular area of the right ventricle, and a total of 500 mL of blood had accumulated in the pericardial space. She was discharged 7 days postoperatively, having made an uneventful recovery. External cardiac massage may cause cardiac disruption, and this should be considered in patients who have secondary hemodynamic instability following successful cardiopulmonary resuscitation.

Continuous antegrade warm blood cardioplegia attenuates augmented coronary endothelium-dependent contraction after cardiac global ischemia and reperfusion.

BACKGROUND: Experiments were designed to evaluate the effect of warm blood cardioplegia on endothelium-dependent contraction of the coronary endothelium after cardiac global ischemia and reperfusion. METHOD: Dogs (n = 12 in each group) were exposed to extracorporeal circulation with the body temperature at 37 degrees C (group 1) or 28 degrees C (groups 2 and 3). The ascending aorta was crossclamped for 120 minutes while continuous infusion of warm blood cardioplegec solution (group 1) or intermittent infusion of cold (4 degrees C) crystalloid cardioplegic solution (group 2) was performed via the coronary arteries through the aortic root. Cardioplegic solution was not used in group 3 animals. The heart was then allowed to function for 60 minutes of reperfusion. Reperfused (groups 1, 2, and 3) and control (group 4) coronary arteries were then harvested for study. RESULTS: Perfusate hypoxia caused endothelium-dependent contraction in the arteries of all four groups that could be attenuated by NG-monomethyl-L-arginine (L-NMMA) or L-NMMA plus D-arginine, but not by L-NMMA plus L-arginine or endothelin receptor A and B antagonist PD 145065. The endothelium-dependent contraction results in groups 2 and 3 (75% +/- 4% and 80% +/- 5%, respectively) were significantly greater than those in groups 1 and 4 (15% +/- 3% and 18% +/- 5%, respectively). Scanning electron microscope studies showed that platelet adhesion and aggregation, areas of microthrombi, disruption of endothelial cells, and separation of the intercellular junction could be found in coronary segments from groups 2 and 3, but not in vessels from groups 1 and 4. CONCLUSION: These experiments suggest that global ischemia and reperfusion enhances hypoxia-mediated endothelium-dependent contraction of the coronary endothelium and damages the ultrastructure. These kinds of changes can be prevented by continuous antegrade infusion of warm blood cardioplegic solution during global ischemia.

CT findings of bronchial transection.

A case of right bronchial rupture demonstrated by computed tomography (CT) is reported. Chest radiographs of a 55-year-old man who sustained blunt chest trauma showed bilateral pneumomediastinum, hydropneumothorax, and subcutaneous emphysema with fracture of the left 3rd and 4th ribs. CT showed wall defect over the right main bronchus with the air in airway contiguous to that in the mediastinum. Bronchoscopy and thoracostomy confirmed the CT findings and the patient was treated by bronchorrhaphy with end-to-end anastomosis. The airway should be meticulously evaluated in cases of mediastinal and subcutaneous emphysema, especially after trauma.

Combination of high-dose chemotherapy, autologous bone marrow/peripheral blood stem cell transplantation, and thoracoscopic surgery in refractory nongestational choriocarcinoma of a 45XO/46XY female: a case report.

A 39-year-old woman having a pure gonadal choriocarcinoma with lung metastasis was referred to our hospital after hysterectomy and bilateral salpingo-oophorectomy. She was found to have a 45XO/46XY karyotype and gonadal dysgenesis. The patient's serum beta-hCG was normalized after six courses of chemotherapy with cisplatin and etoposide of conventional dose (100 mg/m2, 100 mg/m2 x 3 days), but began to fluctuate. Thoracoscopic resection of a remaining pleural lesion was negative for malignancy. However, the disease relapsed as multiple metastatic nodules in bilateral lung fields and the mediastinum. After one course of priming chemotherapy with conventional dose (1 g/m2 cyclophosphamide, 400 mg/m2 carboplatin, and 500 mg/m2 etoposide), high-dose chemotherapy with a total dose of 1500 mg/m2 carboplatin, 1200 mg/m2 etoposide, and 5 g/m2 ifosfamide followed by autologous bone marrow transplantation and peripheral stem cell support was given. Thoracoscopic surgery was performed to resect two residual solitary metastatic lung lesions. With these salvage treatments, the patient obtained complete remission and remained disease free at last follow-up (17 months). Our result suggests that high-dose chemotherapy may be effective in chemosensitive nongestational choriocarcinoma when first chemotherapy has failed.

Impaired endothelium-dependent relaxation of human hepatic arteries after preservation with the University of Wisconsin solution.

OBJECTIVE: To evaluate the effect of University of Wisconsin solution on endothelium-dependent relaxation and contraction of human hepatic arteries in vitro. DESIGN: Human hepatic arteries were harvested from 24 patients with hepatocellular carcinoma who had undergone hepatectomy. SETTING: A tertiary care center. INTERVENTIONS: Human hepatic arteries (n = 6 in each group) were harvested during resection for hepatocellular carcinoma. The arteries in group 1 (i.e., the control group) were immediately studied without preservation. The arteries in group 2 were preserved in cold (4 degrees C) physiological solution for 1 hour, while the arteries in groups 3 and 4 were preserved in University of Wisconsin solution for 1 and 16 hours, respectively. Segments of control and preserved hepatic arteries with or without endothelium were then suspended in organ chambers to measure the isometric force. RESULTS: The relaxation of segments of the hepatic arteries with endothelium in response to acetylcholine and adenosine diphosphate was significantly (P < .05) greater than that of segments without endothelium. The maximal relaxation of hepatic arterial segments with endothelium in groups 3 and 4 in response to acetylcholine was notably different from that of segments in groups 1 and 2. The maximal relaxation of hepatic arterial segments with endothelium in groups 3 and 4 in response to adenosine diphosphate was notably different from that of segments in groups 1 and 2. Perfusate hypoxia (mean +/- SD PO2, 30 +/- 5 mm Hg) caused the endothelium-dependent contraction of the arteries (the median initial tension in groups 1, 2, 3, and 4 was 251%, 233%, 276%, and 260%, respectively; P > .05). CONCLUSIONS: The endothelium-dependent relaxation of human hepatic arteries in response to acetylcholine and adenosine diphosphate was notably attenuated by University of Wisconsin solution. The impaired endothelium-dependent relaxation by University of Wisconsin solution and the prominent endothelium-dependent contraction of human hepatic arteries would favor vasospasm and thrombosis after hepatic transplantation.

Analysis of 24-hour blood pressure data.

Blood pressure is not constant over the course of a 24-h period, but exhibits a predictable and characteristic rise and decline during the day. Although the general shape of this pattern is similar from patient to patient, the knowledge of an individual's blood pressure at one or two points on this curve is of no predictive value in estimating the remainder of the curve. Since critical events are associated with both the maximum and minimum blood pressures that an individual experiences, a characterization of this curve can be very important. The development of antihypertensive agents historically presumed that the reduction in blood pressure associated with therapy would be, if not constant, at least adequate throughout the entire period. However, with the advent of less frequent dosing, the importance of assuring that blood pressure was adequately controlled over the 24-h period became important. This created interest in two basic types of comparisons. One is the comparison of dosing regimens, e.g., comparing a once-a-day regimen with a twice-a-day regimen. The second is a comparison of two therapies with the same regimen; for example, two doses designed to be administered twice a day. The shape of the curves in the first case is inherently different, whereas they have a similar configuration in the second. Many techniques have been attempted, but few recommended for these types of comparisons. Examples include time series, the use of composite indices, univariate statistical procedures, multivariate procedures, and mathematical characterization of the curves with subsequent comparison of model parameters. This presentation will provide a background and overview of several of these methodologies and their relative utility.

Prolonged circulatory arrest in moderate hypothermia with retrograde cerebral perfusion. Is brain ischemic?

BACKGROUND: Circulatory arrest (CA), which provides a bloodless field and good visualization without the need of aortic cross-clamp, is commonly used to facilitate repair of aortic lesions. However, extended periods of CA may impair cerebral metabolism and cause ischemic injury. Studies were performed to evaluate the efficacy of retrograde cerebral perfusion (RCP) in protecting the brain from ischemic injury during a prolonged period of CA in moderate hypothermia. METHODS AND RESULTS: Twenty-three patients (18 men and 5 women) were operated on for aortic lesions (17 acute type A aortic dissection and 6 chronic type A aortic dissection with Marfan's syndrome). The aortic operations were performed with CA (58 to 104 minutes; mean +/- SD, 75 +/- 12 minutes) at a rectal temperature of 23.3 +/- 0.5 degrees C (21 degrees C to 25 degrees C). For RCP, cold (14 degrees C to 18 degrees C) oxygenated blood (300 mL/min) was pumped to the superior vena cava with internal jugular venous pressure of 15 +/- 5 mm Hg. The cardiopulmonary bypass time was 157 +/- 18 minutes. Cortical blood flow during RCP detected by subdural laser Doppler probe was 10 +/- 5% of baseline. Percent oxygen extraction and pyruvate and lactate levels (26 +/- 2% and 0.43 +/- 0.17 and 45 +/- 16 mg/dI) were insignificantly different from those before CA (28 +/- 3% and 0.71 +/- 0.08 and 62 +/- 20 mg/dL, P > .05). Creatine kinase-BB isoenzyme was undetectable. All but 1 patient survived the operation (95.5%) and woke up without neurological deficit. Follow-up (mean, 13 months) was complete in all survivors. There were no late deaths. Cerebral functional studies performed 3 months after discharge showed results insignificantly different from those of the normal control subjects. CONCLUSIONS: There is no evidence of ischemia of the brain during prolonged moderate hypothermic CA with the aid of RCP. Retrograde cerebral perfusion effectively extends the safe time of CA. Deep hypothermia during CA seems unnecessary.