RESUMEN

Reproductive interference due to interspecific hybridization can lead to character displacement among related species with overlapping ranges. However, no studies have examined which reproductive traits are most important in reducing reproductive interference. We conducted molecular analyses of two nuclear genes (28S and Wingless) and a mitochondrial gene (COI) from two closely related ground beetle species, Pterostichus thunbergi and Pterostichus habui (Coleoptera: Carabidae), with overlapping distributions. In addition, we examined four reproductive traits (body size, organ morphologies of intromittent and non-intromittent male genital organs, and female reproductive period) in sympatric and allopatric habitats. We compared male genital morphology using geometric morphometric analysis. The species determined by morphology were classified into separate groups based on the phylogenetic tree constructed by the nuclear gene (Wingless). However, according to the mitochondrial genes examined, P. thunbergi was not monophyletic, whereas at the sympatric sites, these species formed a monophyletic clade. This incongruence suggests that interspecific hybridization and subsequent mitochondrial introgression from P. habui to P. thunbergi have occurred. Concerning genital morphology, both of the intromittent and nonintromittent organs of P. thunbergi differed more from P. habui at the sympatric sites than between allopatric sites, suggesting reproductive character displacement. Pterostichus thunbergi, which likely arrived in P. habui habitat in small numbers, would have experienced stronger selection pressures than P. habui.

Asunto(s)

RESUMEN

PURPOSE: Visual acuity (VA) disturbance other than field defect is important in evaluating patients with pituitary macroadenoma. The purpose of this study was to evaluate MR imaging appearances of optic nerves in patients with pituitary macroadenoma and to ascertain whether visual impairment was correlated with abnormality in optic nerve signal intensity. PATIENTS AND METHODS: Twenty-seven patients with pituitary macroadenoma were examined. Optic nerves were evaluated on T2-weighted images and correlations of signal intensity abnormality with VA disturbance, visual field disturbance, degree of optic chiasm compression, pathologic findings of surgical specimen, and disease duration were statistically analyzed. Correlations between recovery of VA after treatment and the above-mentioned factors were also determined. RESULTS: Coronal T2-weighted images demonstrated unilateral optic nerve hyperintensity lesions in 9 patients. Bilateral signal intensity abnormality of the optic nerve was seen in 5 patients. Signal intensity abnormality of the optic nerve was seen at the site of compression and in the ventral side of the tumor. These patients did not demonstrate signal intensity abnormality posterior to the tumor. Presence of such signal intensity abnormalities was correlated with the degree of optic chiasmal compression and with VA disturbance. Recovery of VA after treatment was correlated with disease duration. CONCLUSION: Hyperintensity of the optic nerves ventral to the pituitary macroadenoma was associated with VA impairment. Recovery of VA after treatment was correlated with disease duration. MR imaging of the optic nerves can provide valuable information for management of pituitary macroadenoma.

Asunto(s)

RESUMEN

Portal vein gas is a rare but potentially lethal condition commonly caused by mucosal damage, bowel distention and sepsis. However, the association between portal vein gas and concurrent chemoradiotherapy has not been documented. We present the case of a 56-year old woman with portal vein gas revealed on computed tomography (CT) after concurrent chemoradiotherapy for advanced oesophageal carcinoma. The portal vein gas totally disappeared 10 days later without any specific treatment. This case demonstrates that the option of close observation for portal vein gas after concurrent chemoradiotherapy is appropriate for consideration. If physical examination, CT findings and laboratory data are unremarkable, it is essential that the patient undergoes close observation and repeated follow-up CT.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Erythropoietin (EPO)-producing renal cell carcinomas (RCC) in patients with chronic renal failure secondary to autosomal dominant polycystic kidney disease (ADPKD) has not previously been reported. We report a case of EPO-producing RCC associated with ADPKD in a 66-year-old woman, and discuss the clinical and radiological findings.

Asunto(s)

RESUMEN

BACKGROUND: Decreased left ventricular volume during head-up tilt plays an important role in triggering syncope in patients with neurally mediated syncope. However, precise changes in left ventricular volume during head-up tilt have not been well investigated. This study was conducted to test the hypothesis that the decline in left ventricular volume during tilt could trigger ventricular mechanoreceptor activation. METHODS AND RESULTS: To investigate the mechanisms of tilt-induced syncope, we measured the temporal changes in left ventricular volume, ejection fraction, cardiac output, and heart rate variability indices during head-up tilt in 25 patients with syncope of undetermined etiology. Eleven patients had a cardioinhibitory response (CI group), 7 patients showed a vasodepressor response (VD group), and 7 patients demonstrated a negative response (NG group). Before syncope, ejection fraction increased most in the CI group, the left ventricular end-diastolic volume declined most in the VD group (VD group, -11.0% +/- 3.3%; CI group, -2.8% +/- 4.8%; NG group, -3.4% +/- 2.2%; P <.005), and the high-frequency spectra increased most in the CI group (CI group, 25.0% +/- 21.0%; VD group, -4.1% +/- 11.7%; NG group, -5.3% +/- 12.7%; P <.01). The vasodepressor response was dependent on left ventricular volume, whereas the cardioinhibitory response was related to the vagal activity reflected by high-frequency spectra. CONCLUSIONS: The precise evaluation of left ventricular volume by an ambulatory radionuclide monitoring system combined with a heart rate variability analysis is considered useful for clarifying the pathophysiology of neurally mediated syncope.

Asunto(s)

RESUMEN

BACKGROUND: The aim of this study was to compare the efficacy of sentinel lymph node biopsy and that of four-node sampling for predicting other nodal status in breast cancer. METHODS: 206 patients with operable breast cancer were enrolled. The identification of sentinel lymph nodes (SLNs) was carried out in 110 patients using a gamma probe after injection of radioactive tin colloids. Four palpable lymph nodes (FNs) were removed from the lower axilla at the first step of axillary dissection in 98 patients. The predictive value of nodal status was compared between SLNs and FNs, based on the pathological findings of all dissected lymph nodes. To examine the relationship between SLNs and FNs, we chose the FNs retrospectively (defined as rFNs) from among all nodes in SLNs. RESULTS: SLNs were identified in 108 (98%) of 110 patients. With one patient having skip metastasis, the accuracy and sensitivity were 99 and 98%, respectively. In the four-node sampling (FNS) group, two in 98 patients had skip metastasis and the accuracy and sensitivity were 98 and 96%, respectively. Findings on the relationship between these methods of biopsy were as follows: (i) rFNs included SLNs in 79 patients (73%); (ii) rFNs partially included SLNs in 24 patients (22%); and (iii) no relationship was evident in five patients (5%). CONCLUSIONS: The accuracy/sensitivity of FNs was comparable to that of SLNs. FNS can be considered to represent a highly promising approach and may be used as an alternative procedure that can be performed safely and easily in any institute.

Asunto(s)

RESUMEN

OBJECTIVE: To describe the acute and subacute changes in hepatic functional reserve using technetium Tc 99m diethylenetriaminepentaacetic acid galactosyl human serum albumin (Tc-99m DTPA GSA) in patients with hepatocellular carcinoma and liver cirrhosis who had undergone transcatheter arterial embolization (TAE). METHODS: Sequential Tc-99m DTPA GSA hepatic scintigraphies were performed prospectively in 26 consecutive patients with hepatocellular carcinoma and liver cirrhosis approximately 1 week before, 2 days after and 1 month after TAE. Counts per 10 seconds of the heart region of interest on 3- and 15-min images and the liver region of interest on a 15-min image were calculated. RESULTS: Clearance index decreased (p < 0.001) and receptor index and modified receptor index increased 2 days after TAE (p < 0.001 and p = 0.004, respectively), but these changes did not persist 1 month later. CONCLUSION: This study has established an expected pattern of behaviour of the liver after TAE, which could be used to monitor progress of patients who undergo the procedure.

Asunto(s)

RESUMEN

The precise measurement of changes in left ventricular volume is important to elucidate the mechanisms of neurally mediated syncope. This study was conducted to determine whether or not a brand-new ambulatory radionuclide monitoring system (C-VEST system) can be clinically used to easily and precisely measure left ventricular volume and function in tilt testing. To assess the repeatability of the C-VEST system, 12 healthy volunteers (mean age 24+/-4 years old) underwent 20 minute head-up tilt testing and we measured the temporal changes in left ventricular volume and ejection fraction twice a day (first and second studies). To investigate the changes in the C-VEST measurements and the detector position in the first and second studies, tilt testing was performed with an 80-degree passive tilt, which is the same as the standard procedure used in diagnosing neurally mediated syncope. The coefficient of repeatability for both the C-VEST and detector position was well within the clinical range (coefficient of repeatability in left ventricular volume ranged from 1.7 to 2.8; coefficient of repeatability in the detector position ranged from 2.3 to 3.1). Precise evaluation of the left ventricular volume can be achieved by an ambulatory radionuclide monitoring system in tilt testing.

Asunto(s)

Asunto(s)

RESUMEN

PURPOSE: To compare interpretation performance on soft-copy presentations, with and without simple image manipulation, and on unmodified hard-copy presentations with regard to detection of pulmonary nodules and masses. MATERIAL AND METHODS: Fifty chest digital radiograph combinations of patients with a total of 60 nodules, 32 of which were 2.0 cm in diameter, were selected for the study. Three readers evaluated three separate image formats: unmodified hard- and soft-copies, and soft-copies with simple image manipulation of lung and mediastinum window settings, and zooming. The screen display was 1600 x 1200 pixels with 8 bits/pixel. RESULTS: The sensitivity, accuracy, detectability, and Az value of the soft-copy systems were clearly inferior to hard-copy evaluation. The mean Az values were 0.921 for unmodified hard-copy, 0.820 for image-manipulated soft-copy, and 0.781 for unmodified soft-copy. CONCLUSION: Soft-copy interpretations were not as sensitive in detecting pulmonary nodules and masses as hard-copy evaluation.

Asunto(s)

RESUMEN

We herein describe thallium-201 single photon emission tomography (T1-201 SPECT) findings in three cases with intracranial angioma. One of the lesions which was associated with chronic encapsulated intracerebral hematoma showed moderate accumulation of T1-201, but, others demonstrated no accumulation. The usefulness and limitations of T1-201 SPECT in differential diagnosis of intracranial mass lesions are discussed.

Asunto(s)

Asunto(s)

RESUMEN

The purpose of this study was to evaluate the effects of gravity and lung volume on regional pulmonary perfusion using technetium-99m macroaggregated albumin (99mTc MAA) single-photon emission tomography (SPET). Twenty-five subjects were classified into three groups according to their position during the injection of the tracer [11 subjects sitting, six supine and eight both supine and prone (S+P) positions]. All of these subjects were injected with the tracer during normal tidal breathing. In the S+P group, half of the tracer was injected while the subject was in each position. The remaining 11 subjects were classified into two groups according to their lung volume during the injection. Supine patients were instructed to hold their breath at residual volume (RV) (five subjects) or total lung capacity (TLC) (six subjects) while receiving the tracer injection. A region of interest with a ventrodorsal axis was defined in the centre of each lung. Profile curves were produced by plotting and normalizing the perfusion values as a percentage of the maximum value. The perfusion distributions for the sitting and S+P positions and at RV were relatively uniform. However, the distributions for the supine position and at TLC showed a gravitational influence [sitting vs. TLC: 87.8%+/-10.4% vs. 67.3%+/-8.7% for % maximum perfusion at +5 pixels from the midpoint of the upper lobe (P<0.00002)]. The gravity-related perfusion inhomogeneity was more prominent in the lower lobe than in the upper lobe. It is concluded that the physiological vertical gravitational gradient should be taken into consideration during the interpretation of lung SPET images. Preferably, patients should be injected with the tracer twice, once in the supine position and once in the prone position, while breathing normally. Alternatively, they may be injected with the tracer once while in the supine position and holding their breath at RV. Either of these protocols should ensure a uniform distribution of tracer.

Asunto(s)

RESUMEN

CONTEXT: Recent studies have demonstrated the potential cost-effectiveness of using 2-fluoro-2-D-[(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET) in the management of non-small cell lung carcinoma (NSCLC), but because of differences in health-care systems, those findings may not hold true in a Japanese hospital. OBJECTIVE: To assess the cost-effectiveness of the chest CT plus chest FDG-PET strategy in Japan. DESIGN: Decision-tree sensitivity analysis based on the two competing strategies of chest CT-alone vs chest CT plus chest FDG-PET. STUDY SELECTION: A simulation of 1,000 patients in whom NSCLC, stage IIIB or less, was suspected was created using baselines of other relevant variables in regard to sensitivity, specificity, mortality, life expectancy, and cost from published data. METHODS: We surveyed the relevant literature for the choice of variables. MAIN OUTCOME MEASURES: Expected marginal cost and expected life expectancy gain for NSCLC patients. RESULTS: The chest CT plus chest FDG-PET strategy yielded an expected life expectancy gain of 0.607 years (7.3 months) per patient, compared with the alternative strategy of chest CT-alone. Using an FDG-PET examination cost of 1.0 x 10(5) yen (around $700 US) per study, the cost increment was 2.18 x 10(5) yen/yr/patient. CONCLUSIONS: The chest CT plus chest FDG-PET strategy in patients with NSCLC is unlikely to be cost-effective in Japan. However, patient life expectancy gain would increase as a result of improved staging of NSCLC. These preliminary results should be confirmed by further studies for specific environments.

Asunto(s)

RESUMEN

To evaluate the potential cost-effectiveness of exercise 201Tl myocardial SPECT in outpatients with angina-like chest pain, we developed a decision-tree model which comprises three 1000-patient groups, i.e., a coronary arteriography (CAG) group, a follow-up group, and a SPECT group, and total cost and cardiac events, including cardiac deaths, were calculated. Variables used for the decision-tree analysis were obtained from references and the data available at our hospital. The sensitivity and specificity of 201Tl SPECT for diagnosing angina pectoris, and its prevalence were assumed to be 95%, 85%, and 33%, respectively. The mean costs were 84.9 x 10(4) yen/patient in the CAG group, 30.2 x 10(4) yen/patient in the follow-up group, and 71.0 x 10(4) yen/patient in the SPECT group. The numbers of cardiac events and cardiac deaths were 56 and 15, respectively in the CAG group, 264 and 81 in the follow-up group, and 65 and 17 in the SPECT group. SPECT increases cardiac events and cardiac deaths by 0.9% and 0.2%, but it reduces the number of CAG studies by 50.3%, and saves 13.8 x 10(4) yen/patient, as compared to the CAG group. In conclusion, the exercise 201Tl myocardial SPECT strategy for patients with chest pain has the potential to reduce health care costs in Japan.

Asunto(s)

RESUMEN

PURPOSE: To assess chemoradiotherapy-induced salivary gland dysfunction using quantitative salivary gland scintigraphy (QSGS), and whether QSGS is capable of predicting the grade of persistent salivary dysfunction after chemoradiotherapy. METHODS: From a time-activity curve using a stimulation test, the washout rate (WR) calculated was assessed. All glands (n = 155) were classified into four groups: a no-therapy group (n = 18), a chemotherapy alone group (n = 31), a radiotherapy alone group (n = 50), and a chemoradiotherapy group (n = 56). Subjective descriptions of xerostomia were recorded 1 year after the completion of the treatment period, and the 32 glands subjected to irradiation with or without chemotherapy were assessed. RESULTS: The WR values were significantly lower in glands that received chemoradiotherapy than in glands treated with radiotherapy alone (mean: 0.75 x 10(-3), n = 40 vs. 0.22, n = 36, p < 0.015), but there was no significant difference in the WR values between the no-therapy group and the chemotherapy alone group. The mean values of WR were lower in the chemoradiotherapy glands than in the radiotherapy alone glands in each of cumulative dose ranges of 1-20, 21-30, and 31-60 Gy. With regard to recovery from xerostomia, the WR values at a cumulative dose range of 20 to 40 Gy were significantly lower in the not improved group (-0.418, n = 16) than in the improved group (0.245, n = 16) (p < 0.0001). CONCLUSION: Chemotherapy per se has no or little adverse effect on salivary function, but combination chemotherapy can deteriorate radiation-induced injury of the salivary glands. QSGS appears useful in predicting the grade of persistent xerostomia following chemoradiotherapy.

Asunto(s)

RESUMEN

UNLABELLED: Although many human cancers can be imaged by 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) and PET, there is little clinical experience with FDG PET in cervical cancer. The purpose of this study was to evaluate the feasibility of FDG PET scans on patients with cervical cancer. METHODS: FDG PET scans were performed on 21 patients with histologically proven uterine cervical cancer (17 newly diagnosed, 4 recurrence). After two levels of transmission scanning, approximately 370 MBq FDG were injected, and dynamic scans over 60 min were obtained at the level of suspected tumors, followed by static scans. Postvoid scans were also obtained in 11 patients to minimize FDG activity in the urinary bladder. FDG uptake was interpreted visually and classified into 4 grades (0 = normal, 1 = probably normal, 2 = probably abnormal and 3 = definitely abnormal). For a semiquantitative index of FDG uptake in tumors, the standardized uptake value (SUV) corrected by predicted lean body mass (SUL) was calculated and compared. The detectability of lymph node metastases by PET was compared with that by CT. RESULTS: Of the 21 newly diagnosed or recurrent cancers, 16 (76%) were detected by FDG PET without use of postvoid imaging (i.e., interpreted as grade 2 or 3). The SULs of tumors ranged from 2.74-13.03, with a mean of 8.15 +/- 3.00 (SUV range 3.68-14.94, mean 10.31 +/- 3.19). There was no significant relationship between the SUL of cervical cancer and the clinical stage. Postvoid FDG PET images substantially reduced the tracer activity in the urinary bladder and improved the visualization of cervical cancers, with three additional cases detected using the postvoid images. In the 11 patients with postvoid imaging, all 11 cancers (100%) were detected. FDG PET detected lymph node metastases in 6 (86%) of 7 patients with known metastases, whereas CT was positive in 4 patients (57%), equivocal in 2 patients (29%) and negative in 1 patient (14%). All PET and CT scans were true-negative in the patients with no lymph node metastases (interpreted as grade 0 or 1 by PET, and as negative by CT). CONCLUSION: These preliminary data demonstrate the feasibility of FDG PET imaging in patients with cervical cancer. FDG PET appears to be promising for detecting untreated or recurrent cervical cancers and lymph node metastases, although the excreted FDG in the urine remains problematic in some cases.

Asunto(s)

Asunto(s)