Pharmacokinetics of sevoflurane uptake into the brain and body

The aim of this study was to investigate the pharmacokinetics of sevoflurane uptake into the brain and body by comparing sevoflurane concentrations in internal jugular-bulb blood (Jsev), arterial blood (Asev) and pulmonary arterial blood (PAsev) over a fixed inspired sevoflurane concentration. Ten patients (aged 51-73 years), undergoing coronary artery bypass grafting surgery were enrolled in this study. They were anaesthetised using a constant 3.5% inspired sevoflurane concentration (CIsev) during the first hour of anaesthesia. During constant volume-controlled ventilation, we measured CIsev and end-tidal sevoflurane (CEsev) using infrared analysis. The sevoflurane concentration in the blood was analysed using gas chromatography, and cardiac output was measured using an Opti-Q pulmonary artery catheter. We found that it took 40 min for the brain concentration to equilibrate with arterial blood (Asev). Both CIsev-CEsev and Asev-PAsev gradients persisted during the study period. There was no further uptake of sevoflurane into the brain after 40 min; however, there was near-constant uptake into the body.

Usefulness of Tc-99m ECD brain SPECT to evaluate the effects of methylprednisolone pulse therapy in lupus erythematosus with brain involvement: a preliminary report

Methylprednisolone pulse therapy (MPT) was introduced to avoid life-threatening complications in systemic lupus erythematosus (SLE) with brain manifestations. However, its efficacy in SLE patients remains uncertain and needs to be objectively evaluated. In this study, technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect regional cerebral blood flow (rCBF) in SLE patients with normal brain magnetic resonance imaging (MRI) findings. Twelve female SLE patients with neuropsychiatric symptoms were enrolled in this study. All patients had normal brain MRI and abnormal Tc-99m ECD brain SPECT findings. The Tc-99m ECD brain SPECT studies were performed 2 weeks after MPT. Pre- and post-MPT serum levels of anticardiolipin antibodies (ACA) and antiribosomal P antibodies (anti-P) were also measured. Before MPT, four patients had positive ACA and seven had positive anti-P. After MPT, all 12 patients demonstrated negative serologic findings and no neuropsychiatric symptoms. After MPT, ten patients showed complete recovery and two showed partial recovery of rCBF in the follow-up Tc-99m ECD brain SPECT images. This imaging is a logical and objective tool for measuring the effects of MPT in SLE patients with brain involvement by the determination of rCBF changes.

Evaluating the changes in alveolar permeability and lung ventilation in patients with chronic renal failure after haemodialysis using 99mTc-DTPA radioaerosol inhalation lung scan

Hypoxaemia occurring in patients with chronic renal failure (CRF) during haemodialysis (HD) has long been known. Several mechanisms of pathogenesis have been proposed. Before and after regular HD, lung ventilation (LV) and alveolar permeability (AP) were measured in 24 male patients with CRF (age, 61-75 years). LV and AP were determined by 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) radioaerosol inhalation lung scan (99mTc-DTPA lung scan). The LV images were visually interpreted according to established criteria, including the presence or absence of an inhomogeneous distribution, inverted base to apex gradient and segmental hypoventilation. The degree of AP in the total right lung was presented as the clearance rate (K; %.min-1) of the time-activity curve from dynamic total right lung images. Ten male normal controls (age, 62-76 years) were enrolled in the study for comparison. Ten of 24 (42%) cases showed an inhomogeneous distribution and eight of 24 (33%) cases showed hypoventilation on equilibrium LV images. After regular HD for 5 h, no significant changes in the LV images were found. Before HD, the CRF patient group (K=1.14+/-0.36%.min-1) had a significantly faster clearance rate than that of normal controls (0.75+/-0.14%.min-1, P<0.05). Moreover, the clearance rate after HD was significantly slower (0.87+/-0.15%.min-1, P<0.05) than that before HD. CRF can predispose patients to LV change and AP damage. After HD, the damage to AP is significantly improved. However, after HD, the change in LV is not significant.

Apertureless near-field Raman spectroscopy

We report on the tip-enhanced Raman spectra of C60 obtained on a custom-built apertureless scanning near-field optical microscope. A commercial atomic force microscope tip coated with 100 nm thickness of gold was used to enhance locally the Raman signal and permit topographic and spectral information to be acquired simultaneously. We present preliminary data which demonstrate the tip enhancement effect using C60 as a test sample.

Time-domain representation of ventricular-arterial coupling as a windkessel and wave system

The differences in shape between central aortic pressure (P(Ao)) and flow waveforms have never been explained satisfactorily in that the assumed explanation (substantial reflected waves during diastole) remains controversial. As an alternative to the widely accepted frequency-domain model of arterial hemodynamics, we propose a functional, time-domain, arterial model that combines a blood conducting system and a reservoir (i.e., Frank's hydraulic integrator, the windkessel). In 15 anesthetized dogs, we measured P(Ao), flows, and dimensions and calculated windkessel pressure (P(Wk)) and volume (V(Wk)). We found that P(Wk) is proportional to thoracic aortic volume and that the volume of the thoracic aorta comprises 45.1 +/- 2.0% (mean +/- SE) of the total V(Wk). When we subtracted P(Wk) from P(Ao), we found that the difference (excess pressure) was proportional to aortic flow, thus resolving the differences between P(Ao) and flow waveforms and implying that reflected waves were minimal. We suggest that P(Ao) is the instantaneous summation of a time-varying reservoir pressure (i.e., P(Wk)) and the effects of (primarily) forward-traveling waves in this animal model.

Keratinase in starter diets improves growth of broiler chicks

The objective of this study was to determine the efficacy of a broad-spectrum protease enzyme, PWD-1 keratinase, upon supplementation to corn-soy starter diets on growth performance of broiler chickens. Three experiments were conducted. In each experiment, 1-d-old broiler chicks were randomly assigned to 24 cage pens of eight birds per pen in a completely randomized design of five experimental treatments and grown to 21 or 26 d of age. Treatments in experiments 1 and 2 were control (C, 21.39% CP), low protein (LP, 18% CP), and LP supplemented with 0.05, 0.1, or 0.15% enzyme preparation (wt/wt). Treatments in experiment 3 were control (C), C+ 0.1% enzyme preparation (C+E) fed starting at either 1 or 5 d of age, LP and LP+ 0.1% enzyme preparation (LP+E). Feeding the LP+E diet produced numerically higher BW at 21 d of age (experiments 1 and 3) and a significantly higher BW at 26 d of age (experiment 2; 1,025 and 1,032 g vs. 965 g for 0.1 and 0.15% vs. LP, respectively, P < 0.05). Feed conversion ratio (FCR) was also improved when chicks were fed the LP+E diet both at 21 (experiment 3) and 26 d of age (experiment 2). In experiment 3, supplementing the C diets with 0.10% enzyme resulted in improvements (P < 0.05) in BW whether the enzyme was supplemented starting at 1 d (767 vs. 695 g for C+E vs. C, respectively) or 5 d of age (764 vs. 695 g for C+E vs. C, respectively). FCR was numerically improved. Furthermore, diets supplemented with the enzyme at any level resulted in reduction of jejunal viscosity at 22 and 27 d of age (P < 0.05). Results of these experiments indicate that the growth of broiler chickens can be significantly improved by dietary supplementation with PWD-1 keratinase.

Unilateral visual impairment and health related quality of life: the Blue Mountains Eye Study

BACKGROUND

There has been considerable recent interest in the impact of unilateral visual impairment on functional status and wellbeing, particularly in relation to second eye cataract surgery.

AIM

To determine if unilateral visual impairment has a measurable impact on health related quality of life (HRQOL) in an older community, as assessed by the generic, multidimensional 36 item short form health survey (SF-36).

METHODS

All participants of the second cross sectional Blue Mountains Eye Study (n = 3508) were invited to attend comprehensive eye examinations and complete an SF-36 questionnaire. Unilateral visual impairment was defined as visual acuity (VA) <6/12 in the worse eye and > or =6/12 in the better eye. Mild visual impairment was defined as VA <6/12 but > or =6/24, moderate as VA <6/24 but > or =6/60, and severe (blindness) as VA <6/60 in the worse eye. Cases with amblyopia (n = 48) were excluded.

RESULTS

Complete data were available for 3108 participants; 227 (7.3%) had unilateral visual impairment (148 mild, 29 moderate, 50 severe). Moderate to severe non-correctable unilateral impairment was associated with poorer SF-36 profiles. After adjusting for age and sex, this group had significantly poorer scores than the unimpaired group in three of eight domains (p<0.05); limitations as a result of physical problems, social function, limitations because of emotional problems, and in the mental component score. Mental domains were more affected than physical domains. Unilateral impairment from undercorrected refraction did not measurably affect HRQOL.

CONCLUSIONS

Moderate to severe non-correctable unilateral visual impairment caused by eye diseases such as cataract had a measurable impact on HRQOL.

Predicting chemotherapy response to paclitaxel-based therapy in advanced non-small-cell lung cancer with P-glycoprotein expression

BACKGROUND

It was reported that multidrug resistance gene 1 (MDR1) encoding human P-glycoprotein (Pgp) may play an important role in multidrug resistance of lung cancer. Therefore, before initiating chemotherapy, it is important to accurately determine the presence of Pgp in lung cancer, to achieve a satisfactory chemotherapy response.

OBJECTIVES

The aim of this study was to compare immunohistochemical analyses of Pgp expression and response to paclitaxel in non-small-cell lung cancer (NSCLC).

METHODS

Before chemotherapy with paclitaxel, 50 patients with stage IIIb or IV NSCLC were enrolled in this study. Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to determine Pgp expression. Chemotherapy response was evaluated in the 3rd month after completion of treatment by clinical and radiological methods.

RESULTS

All of the 28 (100%) cases with good response had negative Pgp expression and 15 of the 22 (68%) cases with poor response had positive Pgp expression (p < 0.05). No significant differences were found for other prognostic factors (age, sex, body weight loss, performance status, tumor cell type, and tumor stage) between good response and poor response groups.

CONCLUSIONS

Although Pgp expression in NSCLC does not fully predict chemotherapy response to paclitaxel-based therapy, detection of Pgp expression will aid in planning paclitaxel-based therapy for patients with advanced NSCLC. Further studies with a larger number of patients and a longer time of follow-up are necessary to confirm our findings.

Detection of cervical lymph node metastases in nasopharyngeal carcinomas: comparison between technetium-99m methoxyisobutylisonitrile single photon emission computed tomography and magnetic resonance imaging

We compared the effectiveness technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) of head and neck in evaluating cervical lymph node (LN) metastasis in nasopharyngeal carcinomas (NPC). Forty NPC patients with cervical LN metastases confirmed histopathologically underwent Te-99m MIBI SPECT and MRI of the head and neck to evaluate cervical LN metastases. For 16 LN lesions with discordant results between Tc-99m MIBI SPECT and MRI, Tc-99m MIBI SPECT could correctly detect 1 metastatic and 10 benign LN lesions as well as MRI could correctly detect 3 metastatic and 2 benign LN lesions. Agreement positive results of Tc-99m MIBI SPECT and MRI could correctly detect all of the remaining 24 metastatic LN lesions. Tc-99m MIBI SPECT has a better specificity but a lower sensitivity for detecting cervical LN metastases in NPC when compared with MRI. The combined use of Tc-99m MIBI SPECT and MRI could increase the accuracy compared with the single use of either Te-99m MIBI SPECT or MRI to detect cervical LN metastases in NPC.

The influences of blood glucose and duration of fasting on myocardial glucose uptake of [18F]fluoro-2-deoxy-D-glucose

During the study of chest using positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG), a significant myocardial FDG uptake can prevent detection of the lesion that is located either behind or closely attached to the heart border. Two well-known and possible factors of myocardial FDG uptake are blood glucose level and fasting duration before FDG PET scanning. This study investigates whether the two factors are related to myocardial FDG uptake. Our study also explores the possibility of eliminating myocardial FDG uptake by controlling patients' blood glucose level and/or fasting duration. Whole-body FDG PET scans performed on 270 consecutive patients performed were reviewed. The study subjects were classified into four grades of myocardial FDG uptake according to the visual interpretation of the FDG PET image hard-copy films. For all study subjects, the blood sugar level and fasting duration before FDG injection were recorded. Then, the blood sugar levels and fasting duration were compared to the visual grade of myocardial FDG uptake for each study subject. About half of the study subjects showed graded 0 myocardial FDG uptake when the blood glucose levels were < or = 120 mg x dl(-1) or when the fasting duration was between 5 and 12 h. One hundred and thirty-one of the 142 (92%) patients with graded 0 uptake were asked to fast for > or = 4 h and had blood glucose levels < or = 120 mg x dl(-1). Based on our findings, we conclude that controlling the patients' blood glucose levels to < or = 120 mg x dl(-1) and at least 5 h fasting should be recommended to decrease myocardial FDG uptake.

Abnormal regional cerebral blood flow on 99mTc ECD brain SPECT in patients with primary Sjögren's syndrome and normal findings on brain magnetic resonance imaging

OBJECTIVE

Technetium-99m ethyl cysteinate dimer (99mTc ECD) single photon emission computed tomography (SPECT) of the brain was used to detect abnormal regional cerebral blood flow (rCBF) in patients with primary Sjögren's syndrome (pSS) and normal findings on brain magnetic resonance imaging (MRI).

METHODS

(99m)Tc ECD brain SPECT was performed to detect brain lesions showing hypoperfusion in 32 female patients with pSS and definite neuropsychiatric symptoms or signs. Seventeen female patients with pSS without neuropsychiatric symptoms and signs were included as a control group for comparison. All of the 49 patients with pSS had normal findings on brain MRI.

RESULTS

99mTc ECD brain SPECT showed brain regions with hypoperfusion in 18 (56.3%) of the 32 patients, and parietal lobes were the most common areas with such lesions. By contrast, 99mTc ECD brain SPECT showed brain regions with hypoperfusion in only three (17.6%) of the 17 patients with pSS without neuropsychiatric symptoms or signs.

CONCLUSION

This study suggests that 99mTc ECD SPECT is a sensitive tool for detecting regions of hypoperfusion in the brains of patients with pSS and neuropsychiatric symptoms or signs and normal findings on brain MRI. However, a review of the literature showed that the (99m)Tc ECD SPECT findings in patients with pSS were non-specific.

Abnormal regional cerebral blood flow in primary antiphospholipid antibody syndrome patients with normal magnetic resonance imaging findings. A preliminary report

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in primary antiphospholipid antibody syndrome (PAPS) patients. The patients had mild neuropsychiatric manifestations and normal brain magnetic resonance imaging (MRI) findings in this preliminary study. Fifteen such female PAPS patients were examined with Tc-99m ECD brain SPECT in order to evaluate the rCBF. In addition, serum anti-cardiolipin antibodies (ACA) and lupus anticoagulant (LA) were simultaneously measured for comparison.

RESULTS

(a) Tc-99m ECD brain SPECT revealed hypoperfusion brain lesions in 12 (80%) of the PAPS patients. Pariental lobes were the most commonly involved areas. (b) 11 (73%) and 9 (60%) cases had positive ACA and positive LA, respectively. In addition, ACA and LA results were correlated to the Tc-99m ECD brain SPECT findings. Tc-99m ECD brain SPECT is a sensitive tool for detecting abnormal rCBF in PAPS patients with mild neuropsychiatric manifestations and normal brain MRI findings.

Increased lung uptake of technetium-99m hexamethylpropylene amine oxime in systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) can affect every organ. Involvement of the lungs in this disease is a significant cause of morbidity and mortality.

OBJECTIVES

To assess pulmonary vascular endothelium damage in SLE by lung uptake of technetium-99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO).

METHODS

Lung uptake of (99m)Tc-HMPAO was measured in 20 SLE patients and for comparison in 25 controls without SLE, referred for brain imaging due to dementia or stroke. Of the 20 SLE patients, 10 had significant clinical pulmonary manifestations. However, all SLE patients had normal chest X-ray findings. Anterior lung image, including a large part of the liver, was taken 10 min after intravenous injection of 20-25 mCi of (99m)Tc-HMPAO. Regions of interest were calculated over the liver and lung.

RESULTS

The mean lung/liver uptake ratio in patients without SLE was 0.36 +/- 0.1. The mean lung/liver uptake ratio in SLE patients was 0.79 +/- 0.58. The difference was significant.

CONCLUSIONS

Our results indicated that determining the ratio of lung/liver uptake of (99m)Tc-HMPAO may be a useful complementary method to assess pulmonary injury in SLE patients.

Technetium-99m tetrofosmin chest imaging related to p-glycoprotein expression for predicting the response with paclitaxel-based chemotherapy for non-small cell lung cancer

Our aim was to use technetium-99m tetrofosmin (Tc-TF) uptake in non-small cell lung cancer (NSCLC) for predicting the chemotherapeutic response of NSCLC to paclitaxel and to compare the results with the expression of multidrug resistance (MDR) - P-glycoprotein (Pgp). Twenty patients with advanced NSCLC were enrolled in this study before chemotherapy with paclitaxel. Tc-TF chest imaging was performed to calculate early and delayed tumor-to-normal lung (T/NL) count-density ratios, as well as washout indexes (WIs). Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to detect Pgp expression. The response to chemotherapy was evaluated by clinical and radiological methods in the third month after completion of treatment. The early and delayed T/NL count-density ratios of patients with good response were significantly higher than those of patients with poor response (p <0.05). However, no significant difference in WI between the two groups of patients was found (p > 0.05). A significantly higher incidence of good response was found in patients with negative Pgp expression (100%) than in patients with positive Pgp expression (40%) (p <0.05). Significantly higher early and delayed T/NL count-density ratios as well as decreased WIs were found in patients with negative Pgp expression than in patients with positive Pgp expression. However, other prognostic factors (age, sex, body weight loss, performance status, tumor stage, and tumor cell type) were not significantly different between the patients with good response and those with poor response. Because Tc-TF chest images can correctly represent the expression of Pgp in NSCLC, it can accurately predict the chemotherapeutic response to paclitaxel.

Detecting parathyroid adenoma using technetium-99m tetrofosmin: comparison with P-glycoprotein and multidrug resistance related protein expression--a preliminary report

The aim of this study was to investigate the relationships among technetium-99m tetrofosmin (Tc-TF) accumulation in parathyroid adenoma and the expression of P-glycoprotein (Pgp) or multidrug resistance related protein (MRP). Before operation, 33 patients with parathyroid adenomas (larger than 1.5 gm) were studied with parathyroid scintigraphy 10 minutes and 2 hours after intravenous injection of Tc-TF before operation. Immunohistochemical analyses (IHA) were performed on multiple nonconsecutive sections of operative parathyroid specimens to detect Pgp or MRP expression. According to the results of IHA, the 33 parathyroid adenomas were separated into four groups: (1) 2 adenomas with both positive Pgp and positive MRP expression, (2) 1 adenomas with positive Pgp but negative MRP expression, (3) 2 adenomas with negative Pgp but positive MRP expression, and (4) 28 adenomas with both negative Pgp and negative MRP expression. All of 28 adenomas in the group 4 could be detected by Tc-TF parathyroid imaging. All of 5 adenomas in the groups 1 to 3 could not be detected by TcTF parathyroid imaging (p < 0.05). Not only the size of parathyroid adenomas, but also significant Pgp or MRP expression limited the sensitivity of Tc-TF parathyroid imaging to localize parathyroid adenomas before operation.

Electroporation for direct spinal gene transfer in rats

We investigated the feasibility of delivering exogenous genes into spinal cord using direct in vivo electrotransfection. Gene transfer to the spinal cord was accomplished via direct intrathecal injection of pE-GFP C1 vector, followed by five electric pulses for 50 ms at 200 V delivered intrathecally. The spinal cords were retrieved and analyzed with fluorescence microscopy, reverse transcription polymerase chain reaction (RT-PCR), and Western blotting. At day 1, 3 or 7 following electroporation a clear GFP expression in spinal cord tissue was detected. The most prominent transfection occurred in the meningeal cells and superficial layer of the spinal cord. Successful transfection was also confirmed with RT-PCR and Western blotting. The expression of GFP protein was peaked between 3 and 7 days after electroporation and significantly decreased at 14 days. No behavioral or spinal neurodegenerative changes were detected at any time point. This study demonstrates that direct in vivo electrotransfection represents an effective and simple method for spinal gene delivery and have a potential to be used clinically, especially, acute or chronic pain.

Development, survival and reproduction of black citrus aphid, Toxoptera aurantii (Hemiptera: Aphididae), as a function of temperature

The development, survival, and reproduction of the black citrus aphid Toxoptera aurantii (Boyer de Fonscolombe) were evaluated at ten constant temperatures (4, 7, 10, 15, 20, 25, 28, 30, 32 and 35 degrees C). Development was limited at 4 and 35 degrees C. Between 7 and 32 degrees C, developmental periods of immature stages varied from 44.2 days at 7 degrees C to 5.3 days at 28 degrees C. Overall immature development required 129.9 degree-days above 3.8 degrees C. The upper temperature thresholds of 32.3, 28.6, 29.3, 27.2, and 28.6 degrees C were determined from a non-linear biophysical model for the development of instars 1-4 and overall immature stages, respectively. Immature survivorship varied from 82.1 to 97.7% within the temperature range of 10-30 degrees C. However, immature survivorship was reduced to 26.3% at 7 degrees C and 33.1% at 32 degrees C. Mean adult longevity was the longest (44.2 days) at 15 degrees C and the shortest (6.2 days) at 32 degrees C. The predicted upper temperature limit for adult survivorship was at 32.3 degrees C. Total nymph production increased from 16.3 nymphs per female at 10 degrees C to 58.7 nymphs per female at 20 degrees C, declining to 6.1 nymphs per female at 32 degrees C. The estimation of lower and upper temperature limits for reproduction was at 8.2 and 32.5 degrees C, respectively. The population reared at 28 degrees C had the highest intrinsic rate of increase (0.394), the shortest population doubling time (1.8 days), and shortest mean generation time (9.5 days) compared with the populations reared at six other temperatures. The population reared at 20 degrees C had the highest net reproductive rate (54.6). The theoretical lower and upper temperature limits for population development, survival and reproduction were estimated at 9.4 and 30.4 degrees C, respectively. The biology of T. aurantii was also compared with three other citrus aphid species.

Tracking the assembly pathway of human immunodeficiency virus type 1 Gag deletion mutants by immunogold labeling

The Pr55gag gene product of human immunodeficiency virus type 1 (HIV-1) is sufficient to direct the formation of retrovirus-like particles (RVLPs). Recent biochemical evidence has indicated the presence of Gag intermediates in the cytoplasm; however, the Gag assembly process into RVLPs remains incompletely defined. The authors present here the subcellular localization of Gag mutant proteins in BSC40 and Jurkat cells by immunoelectron microscopy (IEM). The full Gag/Pol and Gag precursors, a C-terminal deletion mutant lacking a portion of nucleocapsid (NC), and all p6Gag gave rise to similar levels of RVLPs at the cell surface. A C-terminal deletion of all NC and p6Gag abrogated particle formation, whereas p24 was found in patches at the cell surface. Deletion of matrix (MA) sequences from Gag resulted in intracellular particles, and myristylation was not required for particle formation in the context of the MA deletion. Matrix expression was enhanced with Gag/Pol or Env coexpression as determined by semiquantitative IEM. p24 protein was targeted at vacuolar and mitochondrial membranes, but not at Golgi cisternae. In addition, aggregations of Gag intermediates and RVLPs in the cytoplasm, rough endoplasmic reticulum, cisternae, and mitochondria were noted. These results provide defined in situ evidence that HIV-1 particle assembly occurs in the cytosol in addition to budding at most intracellular membranes.

Left ventricular wave speed

Left ventricular (LV) wave speed (LVWS) was studied experimentally and confirmed in theory. Combining the definition of elastance (E) with the equations for the conservation of mass and momentum shows that LVWS is proportional to the square root of ELA, where L is long-axis length and A is the cross-sectional area, and the density of the blood. (We defined ELA = gamma, where gamma is compressibility.) We studied nine open chest, anesthetized dogs, three of which were studied during caval constriction when LV end-diastolic pressure was < or =0 mmHg. The hearts were paced at approximately 90 beats/min, and LV cross-sectional area was measured by using two pairs of ultrasonic crystals; E was calculated from the LV pressure-area loop. A pulse generator was connected to the LV apex, and LVWS was measured by using two pressure transducers: one near the apex and the other near the base. Their distance was measured roentgenographically and compared with the diameter of a reference ball. LVWS ranged from approximately 1 m/s during diastole to approximately 10 m/s during systole. The slope of the log c (where c is wave speed) vs. log gamma was 0.546, which is in agreement with theory (0.5). When gamma < or = 0, LVWS was approximately 1.5 m/s.

Induction of cytochrome P450-dependent monooxygenase in mouse liver and kidney by rutaecarpine, an alkaloid of the herbal drug Evodia rutaecarpa

Rutaecarpine is one of the main alkaloids of an herbal remedy, Evodia rutaecarpa, which has been used for the treatment of gastrointestinal disorder and headache. Effects of rutaecarpine on hepatic and renal cytochrome P450 (CYP)-dependent monooxygenase were studied in C57BL/6J mice. Treatment of mice with rutaecarpine by gastrogavage at 50 mg/kg/day for three days resulted in 57%, 41%, 6-, and 6-fold increases of hepatic microsomal benzo(a)pyrene hydroxylation, 7-ethoxycoumarin O-deethylation, 7-ethoxyresorufin O-deethylation, and 7-methoxyresorufin O-demethylation activities, respectively. However, the treatment had no effects on hepatic oxidation activities toward benzphetamine, N-nitrosodimethylamine, nifedipine, and erythromycin. In the kidney, rutaecarpine-treatment resulted in 2-fold and 42% increases of microsomal benzo(a)pyrene hydroxylation and 7-ethoxycoumarin O-deethylation activities, respectively. The treatment also increased renal 7-ethoxyresorufin O-deethylation activity to a detectable level. Immunoblot analysis of microsomal proteins showed that rutaecarpine-treatment increased the protein levels of CYP1A1 and CYP1A2 in the liver, whereas hepatic level of CYP3A-immunoreacted protein was not affected by rutaecarpine. These CYPs were not detectable in the immunoblot analyses of control and rutaecarpine-treated mouse kidney microsomes. These results indicated that rutaecarpine was a CYP1A inducer and showed potent inductive effects on both CYP1A1 and CYP1A2 in the liver.

Low-dose dexamethasone effectively prevents postoperative nausea and vomiting after ambulatory laparoscopic surgery

PURPOSE

To evaluate the prophylactic effect of low-dose dexamethasone (5 mg) on postoperative nausea and vomiting (PONV) in women undergoing ambulatory laparoscopic surgery. Metoclopramide and saline served as controls.

METHODS

One hundred twenty women (n=40 in each of the three groups) undergoing ambulatory laparoscopic tubal ligation under general anesthesia were enrolled in this randomized, double-blinded, placebo-controlled study. After tracheal intubation, group I received i.v. dexamethasone 5 mg, whereas groups II and III received i.v. metoclopramide 10 mg and saline, respectively.

RESULTS

Patients in group I reported a lower incidence of PONV and requested less rescue antiemetics than those in group III during the first four postoperative hours (P <0.01). Patients in group I reported a lower incidence of PONV than those in groups II (P <0.05) and III (P <0.01) during the 24-hr postoperative period. Groups II and III did not differ from each other in the incidence of PONV and the proportion of patients who requested rescue antiemetics.

CONCLUSION

Prophylactic iv dexamethasone 5 mg significantly reduces the incidence of PONV in women undergoing ambulatory laparoscopic tubal ligation. At this dose, dexamethasone is more effective than metoclopramide 10 mg or placebo.

Murine renal allografts: spontaneous acceptance is associated with regulated T cell-mediated immunity

It was shown >20 yr ago that mice will spontaneously accept renal allografts in the absence of immunosuppression, but the mechanism responsible for this is not understood. We transplanted DBA/2 (H-2(d)) kidneys into nephrectomized C57BL/6 (H-2(b)) mice, and the allografts were spontaneously accepted for >60 days without immunosuppression. In contrast, nonimmunosuppressed cardiac and skin allografts in the same strain combination are rejected within approximately 10 days. The accepted renal allografts have a prominent leukocytic infiltrate, suggesting an ongoing, local immune response. At 60 days post-transplant, the recipients of accepted renal allografts display DBA/2-reactive alloantibodies. They also display DBA/2-reactive delayed-type hypersensitivity responses that are actively counter-regulated by DBA/2-induced TGF-beta production, but not by IL-10 production. These data suggest that a donor-reactive, cell-mediated immune mechanism involving TGF-beta is associated with the spontaneous acceptance of renal allografts in mice.

Comparison of the uptake and clearance of Tc-99m MIBI, Tl-201 and Ga-67 in drug-resistant lymphoma cell lines

Tc-99m sestamibi (MIBI) has been used as a tumor-seeking agent. However, its role in detecting lymphomas has not been widely investigated. The aim of the present study was to determine the uptake and clearance characteristics of Tc-99m MIBI in vincristine-resistant lymphoma cell lines. In addition, thallium-201 (Tl-201) and gallium-67 (Ga-67) uptake and clearance characteristics were evaluated for comparison with Tc-99m MIBI. Drug-resistant lymphoma cell lines (monocyte-like, histiocytic lymphoma, human; B-lymphoma cell line, American Burkitt lymphoma, lymphoblastoid, human; Hodgkin's disease, lymphoid, human) were selected by multistep vincristine treatment up to 50 nM. After incubation of the radiotracers, Tc-99m MIBI, Tl-201 and Ga-67, in medium for 0, 10, 20, 30, 60 or 120 min, the uptake and clearance of each radiotracer were measured in the drug-resistant lymphoma cell lines. In addition, P-glycoprotein expression was determined by immunohistochemical study. In a comparison of the three radiotracers, the uptake of Tc-99m MIBI was the greatest in the studied wild-type lymphoma cell lines. Tc-99m MIBI uptake was much lower in drug-resistant tumor cell lines than in non-resistant cell lines. On the other hand, the uptake characteristics of Tl-201 did not differ between drug-resistant and non-resistant cells. Immunohistochemistry analyses of Ab-1 or JSB indicated that tumor cells expressed MDR-1 protein in all three cell lines. Tc-99m MIBI is a good radiotracer for detecting drug resistance in lymphoma cell lines.

Risk factors for age-related maculopathy: the Visual Impairment Project

OBJECTIVE

To describe the risk factors and associated population attributable risk for age-related maculopathy (ARM) and age-related macular degeneration (AMD) in Australians aged 40 years and older.

METHODS

Residents were recruited from 9 randomly selected urban clusters and 4 randomly selected rural clusters in Victoria, Australia. At locally established test sites, the following information was collected: visual acuity, medical and health history, lifetime sunlight exposure, dietary intake, and fundus photographs. Age-related maculopathy and AMD were graded from the fundus photographs using an international classification and grading system. Backwards logistic regression was used to identify the independent risk factors for ARM and AMD.

RESULTS

The participation rate was 83% (n = 3271) among the urban residents and 92% (n = 1473) among the rural residents. Gradable fundus photographs of either eye were available for 4345 (92%) of the 4744 participants. There were 656 cases of ARM, giving a weighted prevalence of 15.1% (95% confidence limit [CL], 13.8, 16.4); and there were 30 cases of AMD, giving a weighted prevalence of 0.69% (95% CL, 0.33, 1.03). In multiple logistic regression, the risk factors for AMD were as follows: age (odds ratio [OR], 1.23; 95% CL, 1.17, 1.29), smoked cigarettes for longer than 40 years (OR, 2.39; 95% CL, 1.02, 5.57), and ever taken angiotensin-converting enzyme inhibitors (OR, 3.26; 95% CL, 1.33, 8.01). The magnitude of all of these risk factors was slightly less for ARM, and having ever taken blood cholesterol-lowering medications was also significant (OR, 1.67; 95% CL, 1.12, 2.47; P =.001).

CONCLUSION

Smoking is the only modifiable risk factor for ARM and AMD, among the many environmental and systemic factors that were assessed.

Toxic effects of six plant oils alone and in combination with controlled atmosphere on Liposcelis bostrychophila (Psocoptera: Liposcelididae)

Six plant essential oils alone as repellent and fumigant, and in combination with the controlled atmosphere against Liposcelis bostrychophila Badonnel were assessed in the laboratory. These essential oils were extracted from the leaves of six source plants: Citrus tangerina Tanaka, Citrus aurantium L., Citrus bergamia Risso et Poiteau, Pinus sylvestris L., Cupressus funebris End]., and Eucalyptus citriodora Hook. The repellency test indicated that L. bostrychophila adults were repelled by filter paper strips treated with six essential oils. Of these essential oils, the C. funebris oil was most effective followed by that of F. sylvestris, C. tangerina, C. bergamia, and E. citriodora. The average repellency of the C. aurantium oil against L. bostrychophila adults was significantly lower than other five test oils by day 14. These essential oils had a high level of toxicity in the fumigation assay against L. bostrychophila adults at both 10 and 20 ppm. When combined with two controlled atmosphere treatments (12% CO2 + 9% O2, and 10% CO2 + 5% O2, balanced N2), the toxicity of plant oils was enhanced significantly.