Alfentanil attenuates phenylephrine-induced contraction in rat aorta

BACKGROUND AND OBJECTIVES

Alfentanil was reported to relax the rat aorta by direct action on the vascular smooth muscle. The aims of this in vitro study were to examine the effect of alfentanil on phenylephrine-induced contractions in the rat aorta and to determine the cellular mechanism associated with this process.

METHODS

Endothelium-denuded aortic rings were suspended in order to record isometric tension. In the rings with or without 10(-6) mol naloxone or 10(-5) mol verapamil, the concentration-response curves for phenylephrine and potassium chloride were generated in the presence or absence of alfentanil (10(-6), 5 x 10(-5), 10(-4) mol). In the rings exposed to a calcium-free isotonic depolarizing solution, the contractile response induced by the addition of calcium was assessed in the presence or absence of alfentanil (5 x 10(-5), 10(-4) mol).

RESULTS

Alfentanil (5 x 10(-5), 10(-4) mol) attenuated (P < 0.05) the phenylephrine-induced contraction in the ring with or without 10(-6) mol naloxone but had no effect on the phenylephrine-induced contraction in the rings pretreated with verapamil. Alfentanil (5 x 10(-5), 10(-4) mol) produced a significant rightward shift (P < 0.01) in the potassium chloride dose-response curve, and attenuated the contractile response (P < 0.001) induced by calcium in the calcium-free isotonic depolarizing solution in a dose-dependent manner.

CONCLUSIONS

A supraclinical dose of alfentanil attenuates the phenylephrine-induced contraction via an inhibitory effect on calcium influx by blocking the l-type calcium channels in the rat aortic vascular smooth muscle.

Fentanyl reduces desflurane-induced airway irritability following thiopental administration in children

BACKGROUND

Airway irritation is a major drawback of desflurane anesthesia. This study was designed to evaluate the effect of intravenous fentanyl given before thiopental induction on airway irritation caused by a stepwise increase in desflurane in children.

METHODS

Eighty children (2-8 years) were enrolled in a randomized, double-blind study. Forty received saline and 40 received 2 microg/kg of fentanyl intravenously; this was followed by thiopental sodium 5 mg/kg in both groups. Patients were assistant-ventilated with desflurane 1%, which was then increased by 1% every six breaths up to 10%. During this period, cough, secretion, excitation and apnea were graded and the desflurane concentration at which airway irritation symptoms first occurred was recorded. The results were analyzed using Pearson's chi-squared test.

RESULTS

The incidence of typical airway irritation events was lower with fentanyl than with saline (cough, 2.5% vs. 42.5%; secretion, 27.5% vs. 82.5%; excitation, 10% vs. 82.5%; apnea, 20% vs. 65%; P < 0.05). The mean expired desflurane concentration at which the first airway irritation symptom occurred was greater with fentanyl than with saline (7.3% vs. 5.5%, P < 0.05).

CONCLUSIONS

Intravenous fentanyl in children reduces airway complications caused by desflurane.

Missing xy-band Fermi surface in 4d transition-metal oxide Sr2RhO4: effect of the octahedra rotation on the electronic structure

Electronic structures of the 4d transition-metal oxide compound Sr2RhO4 are investigated by angle-resolved photoemission spectroscopy and density-functional electronic structure calculations. In the measured Fermi surfaces (FS) of Sr2RhO4, the xy-band FS sheet expected from the well-established results of the FS of Sr2RuO4 is missing, the volume of which should be different only by one additional electron for Sr2RhO4. The apparent contradiction is resolved by a careful analysis of the band structure where the rotation of octahedra results in the hybridization of e(g) and t(2g) states and thus plays a key role in the determination of the electronic structure near EF. The modification of the FS structure due to the distorted lattice is related to the charge transfer among the orbital states and suggested to be relevant to the metal-insulator transition in Ca(2-x)Sr(x)RuO4.

Impaired long-term memory and long-term potentiation in N-type Ca2+ channel-deficient mice

Voltage-dependent N-type Ca(2+) channels, along with the P/Q-type, have a crucial role in controlling the release of neurotransmitters or neuromodulators at presynaptic terminals. However, their role in hippocampus-dependent learning and memory has never been examined. Here, we investigated hippocampus-dependent learning and memory and synaptic plasticity at hippocampal CA3-CA1 synapses in mice deficient for the alpha(1B) subunit of N-type Ca(2+) channels. The mutant mice exhibited impaired learning and memory in the Morris water maze and the social transmission of food preference tasks. In particular, long-term memory was impaired in the mutant mice. Interestingly, among activity-dependent long-lasting synaptic changes, theta burst- or 200-Hz-stimulation-induced long-term potentiation (LTP) was decreased in the mutant, compared with the wild-type mice. This type of LTP is known to require brain-derived neurotrophic factor (BDNF). It was found that both BDNF-induced potentiation of field excitatory postsynaptic potentials and facilitation of the frequency of miniature excitatory postsynaptic currents (mEPSCs) were reduced in the mutant. Taken together, these results demonstrate that N-type Ca(2+) channels are required for hippocampus-dependent learning and memory, and certain forms of LTP.

Effect of cryoprotectants on the reconstitution of surfactant-free nanoparticles of poly(DL-lactide-co-glycolide)

Various cryoprotectants were tested to reconstitute the surfactant-free nanoparticles of poly(DL-lactide-co-glycolide) (PLGA). When 2.0% (w/v) of sucrose, trehalose and lactose were used, nanoparticles were completely reconstituted into aqueous solution and particle size was not significantly changed. Above 1.0% (w/v) of sucrose, trehalose and lactose, nanoparticles are well reconstituted whereas it was precipitated with 1.0% (w/v) of mannitol. Drug-encapsulated surfactant-free nanoparticles were quite reconstituted when 2.0% (w/v) of sucrose, trehalose and lactose. Drug release kinetics of nanoparticles was not significantly changed by cryoprotectants.

Three-day regimen of fluorouracil and cisplatin combination chemotherapy for persistence, metastatic or recurrent uterine cervical cancer

15049

Background: The five-day infusion of FP(5-fluorouracil, cisplatin) combination therapy is one of the most popular regimens for advanced cervical cancer, which has yield a 50∼60% response rate. There is some variance in the FP combination, for example, longer infusion of FP requiring longer hospitalization as well as causing more discomfort to the patients. This study was designed to assess the therapeutic effect and toxicities of three day regimen of FP combination chemotherapy instead of five day regimen for disseminated or recurrent cervical cancer. Methods: From July 1996 through April 2001, 39 patients with advanced or recurrent cervical cancer were enrolled in the study. The regimen consisted of continuous 12-hour infusion of 5-FU(5-fluorouracil) at 1000 mg/m2/day plus bolus infusion of cisplatin at 25mg/m2/day for 3 days. The treatment was repeated every 3 weeks. Results: Thirty five patients with a median age of 53 years were evaluable for response during the median follow up of 21.5 months. The response rate was 45.7% (4 CR and 12 PR), and the median duration of the overall survival was 45 months. Toxicity was acceptable with no treatment related mortality. Neutropenia in grade 3 or more was seen in 16% with 4 febrile episodes throughout a total 232 cycles. It did not appear alopecia and gastointestinal trouble in grade 3 or more. Conclusions: These results revealed that the toxicity of 3 day regimen of 5-FU and cisplatin is acceptable and the efficacy comparable to that of 5 day regimen.

No significant financial relationships to disclose.

Phase II study of genexol (paclitaxel) and carboplatin as first-line treatment of advanced or metastatic non-small-cell lung cancer (NSCLC)

17049

Background: Genexol is a polymeric micelle loaded paclitaxel without Cremophor EL (CrEL). CrEL has been shown to cause hypersentivity reaction and neuropathy. To evaluate and efficacy, we conducted a phase II study of CrEL-free paclitaxel (genexol) and carboplatin in patients (pts) of advanced or metastatic NSCLC. Methods: Eligibility criteria included: stage IIIB or IV NSCLC without previous chemotherapy and radiotherapy; written informed consent; measurable lesion; age 18–75; ECOG PS 0–3; adequate bone marrow, liver, and renal function; and no CNS disease. The patients received genexol 225 mg/m2 IV on day 1, followed by carboplatin AUC = 6 IV on day 1 every 3 weeks. Primary end points are response and toxicity. Response evaluations were performed after cycles 2, 4, and 6 of chemotherapy according to the RECIST criteria. Results: 36 pts were enrolled between November 2002 and November 2005. Pts characteristics: median age 63 years (range 45–73), median ECOG PS 1 (range 0–3), 13 stage IIIB and 23 IV, 21 adenocarcinoma and 14 squamous cell carcinoma, and 1 large cell carcinoma. At present, 30 pts were evaluable for response and toxicity. Meidan number of treatment cycles was 4 (range 1–6). Seven pts needed dose reduction. Thirteen pts achieved partial response and 13 pts had stable disease. The response rate 43.3%. Grade (gr) 4 neutropenia occurred in 11 pts (36.7%). Gr 1/2 sensory neuropathy occurred in 13 pts (43.3%) and gr 3/4 sensory neuropathy occurred in 5 pts (50%) among 10 pts over 65 year old. Other toxicities included neutropenic fever in 9 pts (30%), gr 4 thrombocytopenia 3 patients (10%), gr 2 hepatic dysfunction 3%, and gr 3 fatigue 10%. Treatment related mortality was not occurred. Complete analysis will be presented. Conclusions: In this trial, the combination of genexol and carboplatin showed a significant activity with acceptable and manageable toxicities as first line treatment for patients with advanced or metastatic NSCLC and dose reduction needed in older patients.

No significant financial relationships to disclose.

Combination of local tumor invasiveness (LTI) and International Prognostic Index (IPI) provides better predictive value in extranodal NK/T-cell lymphoma, nasal type (NTCL)

17503

Background: In contrast to B-cell lymphomas, NK/T-cell lymphomas have unique clinical pattern (local invasiveness; Blood. 2005;106:3785). Prognostic factors were evaluated according to IPI as well as LTI and compared with the other prognostic model (Lee J, et al JCO 2006). Methods: 176 patients diagnosed with NTCL between 1992 and 2004 were analyzed. Overall survival (OS) and progression-free survival (PFS) were compared according to IPI, IPI combined with LTI, and the other model. LTI was briefly defined as follows: bony invasion or perforation or skin invasion (upper aerodigestive tract); serosal invasion or perforation (gastrointestinal tract); tumor more than 5cm or invasion of deep extradermal structures (skin); and neurovascular or bony invasion (muscle). Results: After a median follow-up period of 80 months, 5-year (y) OS and PFS were 33% and 25%, respectively. The IPI risk group was predictive of OS and PFS (5-y OS 52%, 23%, 10%, and 4%, respectively, P < .0001; 2-y PFS 47%, 31%, 5%, and 4%, respectively, P < .0001) but failed to show survival differences between the high-intermediate and high risk groups (P = .0737). However, once both IPI and LTI are combined, there were significant differences in OS and PFS between the IPI score 0–2/LTI-, IPI score 0–2/LTI+, IPI score 3–5/LTI-, and IPI score 3–5/LTI+ groups (5-y OS 60%, 14%, 7%, and 4%, respectively, P < .0001; 2-y PFS 53%, 21%, 9%, and 4%, respectively, P < .0001). OS and PFS were also affected by the other prognostic model but this model failed to show survival differences among the risk groups (P = .1382). Conclusions: Combination of local tumor invasiveness and International Prognostic Index provides better predictive value in extranodal NK/T-cell lymphoma, nasal type.

No significant financial relationships to disclose.

Gender difference in susceptibility to smoking in Korean lung cancer patients having smoking habits

17158

Background: There were some controversies whether women were more or less susceptible to the carcinogenic effect of cigarette smoke and the decline of forced expiratory volume in 1 second (FEV1) to pack-years compared to men. Methods: In this study, we included all lung cancer patients having smoking habits who was histologically diagnosed and performed pulmonary function testing at the time of diagnosis from September 2001 through December 2005. We estimated individual susceptibility to smoking using a formula (SI, susceptibility index) of (100% predicted FEV1)/pack-years. Results: Of 858 lung cancer patients, sex ratio (M/F) was 14.6 (803/55). Past smokers were in 236 (29.3%) for men, 11 (20.0%) for women. Most common hsitologic type was squamous cell carcinoma (477), adenocarcinoma (191), small cell carcinoma (147), adenosquamous cell carcinoma (14), large cell carcinoma (14), NSCLC cell type not specified (15). Pack-years were 41.3 ± 18.9 for men, 29.2 ± 20.4 for women (P = 0.000). FEV1 % was 78.7 ± 23.3 for men, 79.4 ± 22.9 for women (P = 0.832). As for SI, there were no differences between men (0.65 ± 1.1) and women (0.72 ± 1.6) (P = 0.688). Conclusions: Although lung cancer women having smoking habits showed lower pack-years, there were no gender differences in terms of FEV1 decline to cigarette smoking.

No significant financial relationships to disclose.

Randomized phase II trial of neoadjuvant vs. adjuvant docetaxel plus cisplatin in patients with locally advanced gastric carcinoma: An interim analysis

4030

Background: The perioperative treatment strategy for locally advanced gastric cancer (LAGC) has not been clearly established. We conducted a randomized phase II study of neoadjuvant vs. adjuvant docetaxel/cisplatin (DC) chemotherapy in LAGC. Methods: LAGC was radiographically defined by CT and PET. Pts were randomized to receive neoadjuvant or adjuvant DC (docetaxel 36 mg/m2 + cisplatin 40 mg/m2 on D1, D8, q 3 wks X 3 cycles) according Japanese staging system (IIIa, IIIb, IV M-, and IV with a single M+ node). Results: All planned 88 pts in 44 per each arm were enrolled between Jan 2003 and Nov 2005. One pt was not eligible. The median age was 57 yrs vs. 58 yrs, PS 1 90.7% vs. 84.1%, and stage III/IV 72.1%/27.9% vs. 70.5%/29.5% in the neoadjuvant and adjuvant arm, respectively. Clinical response rate of 42 evaluable pts in neoadjuvant arm according to WHO criteria was 64.3% (95% CI 49.8–78.8%) with CR 2.4%, PR 61.9%, SD 31.0%, and PD 4.7%. There was no treatment related death. Comparison of G3/4 adverse events in neoadjuvant vs. adjuvant arm were; leukopenia 14.0% vs. 32.4% (p=0.04), neutropenia 37.2% vs. 62.2% (p=0.02), febrile neutropenia 0% vs. 2.7%, diarrhea 2.3% vs. 10.8%, stomatitis 2.3% vs. 8.1% (p=NS). There were no difference in the postoperative morbidity and the duration of hospital stay between both arms, but surgery was delayed in one pt who developed tuberculosis during neoadjuvant chemotherapy. Downstaging of the T stage could be obtained in 6 (14.3%) among 42 evaluable pts in neoadjuvant arm, according to EUS. Conclusions: Both neoadjuvant and adjuvant DC chemotherapy were relatively well tolerated in LAGC, with the lower incidence of G3/4 toxicities in neoadjuvant arm. Neoadjuvant DC showed a high response rate and a modest downstaging effect. (Supported by National Cancer Center Grant; Docetaxel was provided by Sanofi Aventis Korea)

[Table: see text]

No significant financial relationships to disclose.

A multicenter phase II study of pemetrexed and cisplatin in patients with advanced gastric cancer (AGC)

14008

Background: Pemetrexed is a novel folate antimetabolite, and it inhibits a number of folate-dependent enzymes. This agent has demonstrated activity in a variety of tumor types including AGC. This study was performed to evaluate the combination of pemetrexed and cisplatin in the treatment of AGC. The primary endpoint was response rate, and secondary endpoints were duration of response, time to progressive disease, time to treatment failure, overall survival, and toxicity. Methods: Patients with stage IV AGC not to be amendable to curative surgery and measurable disease were eligible. Pemetrexed 500 mg/m2 and cisplatin 75 mg/m2 were given on day 1, every 21 days. Treatment was supplemented with folic acid, vitamin B12, and dexamethasone. Response was assessed by RECIST, and toxicity was assessed by NCI-CTC v 2.0. Results: From October 2003 to September 2004, 51 patients were enrolled, but 1 did not meet the eligibility criteria. There were 37 men and 13 women with a median age of 56 years (range, 24–69) and an ECOG PS 0/1 for 14/36 patients; all had metastatic disease. Of 50 evaluable patients, there were no complete responses, and 13 had confirmed partial responses (26%; 95% CI, 14.6%-40.3%). Fifteen patients (30%) had stable disease, and 21 (42%) progressed, and 1 (2%) was unknown. Among 13 responders, the median durarion of response was 3.60 months (95% CI, 2.80–9.40). Median time to progressive disease was 2.8 months (95% CI, 2.20–4.40), and median overall survival was 6.6 months (95% CI, 4.80–10.40). The median time to treatment failure was 2.10 months (95% CI, 1.00–2.80). Survival estimates were 32.0% at 3 months and 7.0% at 6 months. A total of 212 cycles were administered to 51 patients (median 4 [range, 1–13]). Based on 51 patients, most common grade 3/4 hematologic toxicities were neutropenia (49.0%), leukopenia (19.7%), and anemia (13.7%); the most common grade 3/4 nonhematologic toxicities were hyponatremia (15.7%), anorexia (9.8%), nausea (7.8%), and vomiting (7.8%). Conclusions: : The combination of pemetrexed and cisplatin in the current dose and schedule has a modest activity and a mild toxicity profile in patients with AGC. Further study is warranted using a different dose and treatment schedule.

[Table: see text]

Drosophila homolog of APP-BP1 (dAPP-BP1) interacts antagonistically with APPL during Drosophila development

beta-Amyloid precursor protein binding protein 1 (APP-BP1) was previously identified based on its binding to the carboxyl terminal of beta-amyloid precursor protein. In this report, we have discovered that a mutation of dAPP-BP1 (Drosophila ortholog of APP-BP1) hinders tissue development, causes apoptosis in imaginal disc cells, and blocks the NEDD8 conjugation pathway. We show that dAPP-BP1 specifically binds the intracellular domain of APP-like protein (APPL). The dAPP-BP1 mutation partially suppresses the abnormal macrochaete phenotype of Appl(d), while overexpression of dAPP-BP1 causes abnormal macrochaetes. When APPL is overexpressed, the normal bristle pattern in the fly thorax is disturbed and apoptosis is induced in wing imaginal discs. APPL overexpression phenotypes are enhanced by reducing the level of dAPP-BP1. APPL overexpression is shown to inhibit the NEDD8 conjugation pathway. APPL-induced apoptosis is rescued by overexpression of dAPP-BP1. Our data suggest that APPL and dAPP-BP1 interact antagonistically during Drosophila development.

Influence of quantum size effects on island coarsening

Surface x-ray scattering and scanning-tunneling microscopy experiments reveal novel coarsening behavior of Pb nanocrystals grown on Si(111)-(7 x 7). It is found that quantum size effects lead to the breakdown of the classical Gibbs-Thomson analysis. This is manifested by the lack of scaling of the island densities. In addition, island decay times tau are orders of magnitude faster than expected from the classical analysis and have an unusual dependence on the growth flux F (i.e., tau is approximately 1/F). As a result, a highly monodispersed 7-layer island height distribution is found after coarsening if the islands are grown at high rather than low flux rates. These results have important implications, especially at low temperatures, for the controlled growth and self-organization of nanostructures.

Midazolam depresses carotid body chemoreceptor activity

BACKGROUND

Although the contribution of the gamma-aminobutyric acid (GABA) receptor system in peripheral chemosensation is unclear, immunohistochemistry has demonstrated the presence of GABA-ergic receptors in mammalian carotid bodies. We hypothesized that an activation of the carotid body GABA receptors would counteract the depolarizing effect of hypoxia.

METHODS

The carotid body with arterial supply and the carotid sinus nerve was removed en bloc from New Zealand White rabbits and placed in a perfusion chamber. The carotid body preparation was perfused via the cut common carotid artery with a modified Tyrode's solution at a rate of 3.5-4.5 ml/min with a constant pressure of 45 cmH2O. The carotid sinus nerve firing frequency (Hz) was recorded at two different oxygen tension levels during perfusion with midazolam of 1, 10 and 100 microg/l.

RESULTS

The frequency was decreased by midazolam in a dose-dependent manner (n = 8). Firing frequencies (mean +/- SEM) at the low oxygen tension level decreased from 643.13 +/- 67.2 Hz in the control to 554.5 +/- 67.7 Hz (P = 0.054 vs. control), 509.01 +/- 100.5 Hz (P < 0.012 vs. control) and 422.6 +/- 77.3 Hz (P < 0.001 vs. control) during perfusion with midazolam of 1, 10 and 100 microg/l, respectively.

CONCLUSION

Midazolam depresses carotid body chemoreceptor activity in a dose-dependent manner.

Quasimonoenergetic electron beam generation by using a pinholelike collimator in a self-modulated laser wakefield acceleration

A relativistic electron bunch with a large charge (>2 nC) was produced from a self-modulated laser wakefield acceleration configuration. For this experiment, an intense laser beam with a peak power of 2 TW and a duration of 700 fs was focused in a supersonic He gas jet, and relativistic high-energy electrons were observed from the strong laser-plasma interaction. By passing the electron bunch through a small pinholelike collimator, we could generate a quasimonoenergetic high-energy electron beam, in which electrons within a cone angle of 0.25 mrad (f/70) were selected. The beam clearly showed a narrow-energy-spread behavior with a central energy of 4.3 MeV and a charge of 200 pC. The acceleration gradient was estimated to be about 30 GeV/m. Particle-in-cell simulations were performed for comparison study and the result shows that both the experimental and simulation results are in good agreement and the electron trapping is initiated by the slow beat wave of the Raman backward wave and the incident laser pulse.

250 DISTRIBUTION OF HISTONE macroH2A1 IN BOVINE PRE-IMPLANTATION EMBRYOS DERIVED FROM PARTHENOGENETIC ACTIVATION AND IN VITRO FERTILIZATION

It is known that heterochromatin is characterized by the presence of the histone variant of macroH2A1. MacroH2A1 is a core variant histone with a hybrid structure consisting of a domain that resembles a full-length histone H2A1 followed by a large nonhistone domain. We have previously studied the dynamic changes of macroH2A1 accumulation during the pre-implantation developmental period in the mouse. In the present study, we investigated the distribution of microH2A1 in bovine metaphase II oocytes and pre-implantation embryos at 2-, 4-, 8-, 16-cell, and morula stages as well as blastocysts harvested at Days 8, 9, 10, 11, 12, and 13 following activation and in vitro fertilization (IVF). To generate parthenotes, denuded and in vitro-matured oocytes were activated using a combined treatment of calcium ionophore A23187, cycloheximide (CHX), and 6-dimethylaminopurine (6-DMAP). Five oocytes and pre-implantation embryos at each stage of development were used to follow the development expression pattern of microH2A1 by immunocytochemistry. The cross-reactivity of the primary antibody against mouse microH2A1 was verified by Western blot analysis with bovine fibroblasts. Another staining control included immunostaining with antibody against histone molecules. The stained embryos were observed by laser-scanning confocal microscopy and epiflourescence microscopy. No microH2A1 stain was observed in bovine oocytes or pre-implantation embryos up to the expanded blastocyst stages. In the IVF group, the macroH2A1 was first found in elongated blastocysts (Day 11) after hatching. We observed different expression patterns of macroH2A1 in activated vs. IVF bovine embryos. In the parthenote group, we failed to find robust expression even when embryos were cultured for 13 days. Moreover, the pattern of macroH2A1 expression in bovine embryos was different fromn that in the mouse, in which the onset of macroH2A1 expression occurred by the 16-cell morula stage. These results suggest species differences in the establishment of epigenetic signals. This work was supported by grants from USDA to X. Y. and X. C. T.

ICA and water in Korea--overview

The natural water quality in Korea has improved significantly in the last 20 years since major collective national initiatives were implemented by governmental agencies, non-governmental organizations, and professionals among many others. Recently instrumentation, control, and automation (ICA) technology has become one of the most important technologies for carrying out this task. Korea has become especially well known with a strong reputation for information technology and international business with commercial products like semi-conductors, computers, mobile phones, computer games, and other electronic products. In this paper the background of Korean water quality is reviewed and several of the most significant national projects related to ICA are discussed. The major projects may include the Automatic Monitoring Network of River Water Quality and the Integrated Management System of Wastewater Treatment Plants in Upper Basin Area of Multi-purpose Dams.