Magnetic resonance imaging of benign phyllodes tumors of the breast

Magnetic resonance imaging (MRI) has the potential to become a useful adjunct in breast imaging. Contrast-enhanced breast MRI has demonstrated a high sensitivity in the detection of benign and malignant breast disease. Our study aimed to correlate the dynamic contrast-enhanced MRI appearance of benign phyllodes tumor of the breast with histopathologic findings. We retrospectively reviewed the MRI findings in eight patients with benign phyllodes tumor of the breast to describe the image characteristics of this disease. The architectural features and enhancement patterns of this tumor were assessed and compared with other breast diseases. MRIs demonstrated some characteristics for large benign phyllodes tumors (more than 3 cm in size). On T(2)-weighted images, they were imaged as spotted tumors in high to iso signal intensity with cystic components or septations inside. In the time-signal intensity curve for the eight patients in our study who underwent dynamic MRI, we demonstrated two patterns of their curve: rapidly and gradually enhanced. In conclusion, MRI findings in benign phyllodes tumor include dynamic curves of gradually and rapidly enhancing types, and a low and inhomogeneous signal intensity on T(2)-weighted images compared with fibroadenoma. These findings appear to be useful for diagnosis.     

Regulatory volume increase after secretory volume decrease in colonic epithelial cells under muscarinic stimulation

To address the question of whether colonic secretory cells change their volume in response to carbachol (CCh) stimulation and, if so, the mechanisms involved therein, we used two-photon laser scanning microscopy to measure the volume of individual epithelial cells in the fundus region of crypts isolated from the guinea-pig distal colon. We also measured the volume of human colonic epithelial T84 cells using an electronic sizing technique. Both types of colonocytes responded to stimulation by CCh with shrinkage and then underwent a regulatory volume increase (RVI), even during continued stimulation by CCh. The secretory volume decrease (SVD) induced by CCh was antagonized by atropine, BAPTA loading and niflumic acid, a blocker of Ca²⁺-activated Cl^– channels. An increase in the intracellular free [Ca²⁺] was observed with fura-2 during these volume responses to CCh. Removal of all Na⁺ or K⁺ or of most of the Cl^– from the extracellular solution abolished the RVI, but not the preceding SVD. The RVI, but not the preceding SVD, was abolished by bumetanide, a blocker of the Na⁺-K⁺-2Cl^– cotransporter. We conclude that guinea-pig crypt colonocytes and human T84 cells exhibit a cytosolic Ca²⁺-dependent SVD and undergo a subsequent RVI that is dependent on the operation of Na⁺-K⁺-2Cl^– cotransporters.     

Effects of telencephalic ablation on shoaling behavior in goldfish

The role of the telencephalon in the shoaling behavior of the goldfish, Carassius auratus, was investigated. Experiments were carried out in a tank divided into three compartments. Subjects were introduced into the center compartment of the tank. In the activity phase, subjects swam alone, and swimming distance was used as an index of activity. In the shoaling behavior phase, a stimulus fish was introduced into one of the side compartments, and the time spent near the side compartment by the subject was used as index of shoaling behavior. After these measurements were made, visual and motor abilities were examined using the optomotor response. Subjects then received surgery and the same procedure was repeated. In Experiment 1, the effects of total ablation of the telencephalon and a section of the olfactory tract (OlT) were examined. The ablation group exhibited reduced activity and shoaling behavior compared with the sham and OlT group. In Experiment 2, the role of the dorsal part of the telencephalon was examined after damaging the dorsomedial and dorsolateral telencephalon. Lesions in either portion had no effect and no simple visual or motor deficits were seen. These results suggest that the ventral part of the telencephalon mediates shoaling behavior.     

CD4+ T cells migrate from airway to bone marrow after antigen inhalation in rats

BACKGROUND: IL-5-producing T lymphocytes increase in rat bone marrow after inhalational challenge with allergen. OBJECTIVE: To test the hypothesis that T cells migrate from the airways to the marrow, we examined the trafficking of T cells in Brown Norway rats after sensitization and challenge with ovalbumin. METHODS: Purified CD4+ T cells, harvested from cervical lymph nodes of naive and ovalbumin-sensitized donors, were labeled with carboxy fluorescein diacetate succinimidyl ester; 20 x 10(6) cells were placed in the trachea of naive or sensitized recipients under anesthesia, and 18 hours later, animals were challenged with inhaled ovalbumin. Cells were harvested 24 hours later from the bone marrow, bronchoalveolar lavage fluid, lungs, the lung blood pool of cells, lung draining lymph nodes, peripheral blood, and spleen. RESULTS: The number of carboxy fluorescein diacetate succinimidyl ester-positive cells, measured by fluorescence-activated cell sorter, in the bone marrow of ovalbumin sensitized, primed T-cell recipients was higher than either the sham-sensitized, primed T-cell recipients or sham-sensitized, naive T-cell recipients (P < .05). The number of eosinophils in both bone marrow and bronchoalveolar lavage fluid was increased in ovalbumin-sensitized, primed T-cell recipients. The expression of the T-cell chemoattractants eotaxin and IL-16, evaluated by immunohistochemistry, was higher in the bone marrow of ovalbumin-sensitized, primed T-cell recipients. CONCLUSIONS: CD4+ T cells travel from airway to bone marrow after antigen inhalation. The homing of the CD4+ T cells might be facilitated by eotaxin and IL-16 expression in the bone marrow and might contribute to the stimulation of eosinophilopoiesis after airway allergen exposure.     

Acetaldehyde induces histamine release from human airway mast cells to cause bronchoconstriction

BACKGROUNDS: Approximately half of the Japanese asthmatics experience exacerbation of asthma after alcohol consumption. We previously reported that this phenomenon is probably caused by histamine release from mast cells by acetaldehyde stimulation. However, no reports have described the effects of acetaldehyde on human airway mast cells. The purpose of the present study was to demonstrate acetaldehyde-induced histamine release from human airway mast cells with subsequent airway smooth muscle contraction and to investigate the ensuing mechanisms. METHODS: Human tissue samples were prepared from the lungs resected from patients with lung cancer. The effect of acetaldehyde on airway muscle tone and the concentration of chemical mediators released in the organ bath were measured before and after acetaldehyde stimulation. Mast cells were prepared from lung parenchyma by the immunomagnetic method and then stimulated with acetaldehyde to determine the chemical mediators released. RESULTS: Acetaldehyde (>3 x 10(-4) M) increased airway muscle tone, which was associated with a significant increase in the release of histamine, but not thromboxane B2 or cysteinyl-leukotrienes. A histamine (H1 receptor) antagonist completely inhibited acetaldehyde-induced bronchial smooth muscle contraction. Acetaldehyde also induced a significant histamine release from human lung mast cells and degranulation of mast cells. CONCLUSIONS: The present results strongly suggest that acetaldehyde stimulates human airway mast cells to release histamine, which may be involved in bronchial smooth muscle contraction following alcohol consumption.     

Steroid injection to vocal nodules using fiberoptic laryngeal surgery under topical anesthesia

Since 1990, we have performed steroid injection into the vocal fold by fiberoptic laryngeal surgery (FLS) under local anesthesia. In this study, the usefulness of this method was evaluated in 28 patients with vocal nodules. Under monitoring using a fiberoptic laryngoscope, a curved injection needle was inserted via the oral cavity and steroid was injected. Endoscopic findings showed that the vocal nodule had disappeared in 17 patients of the 27 patients and decreased in 10 after injection. The maximum phonation time was 10.9 s before operation and 13.9 s after operation, showing a significant increase (P<0.05), and the mean flow rate also showed a significant improvement (P<0.05). The patients self-rating concerning hoarseness demonstrated great improvement after injection. This technique can be performed under local anesthesia in combination with voice therapy on an outpatient basis, and it is considered to be useful for treating vocal nodules.     

Risk factors for intraoperative hypotension in traumatic intracranial hematoma

Patients suffering from traumatic intracranial hemorrhage (TICH) may experience an episode of catastrophic intraoperative hypotension (IHT), after decompression of the brain. The aim of this study was to investigate the risk factors for IHT during emergency craniotomy A total of 67 patients, who underwent emergency craniotomy due to TICH, were divided into two groups: IHT ( n=31 ) or without IHT ( n=36 ). Data concerning (1) age; (2) gender; (3) mechanism of injury; (4) Glasgow Coma Scale (GCS) on admission; (5) abnormality of the pupils (anisocoria or mydriasis); (6) mean arterial blood pressure; (7) heart rate; (8) time elapsed before craniotomy from injury; (9) initial brain CT scans; (10) duration of craniotomy; and (11) total infusion or urine volume until craniotomy were collected prospectively as IHT risk factors. Low GCS score (<5), tachycardia (heart rate >112min(-1)) and hypertension (mean blood pressure >131mmHg) before emergency craniotomy were strongly ( P<0.05 ) associated with IHT. Delayed surgery (>173min until craniotomy) also had a significant ( P<0.005 ) effect on IHT. The risk factors for IHT were considered as a low GCS score on admission, tachycardia, hypertension before emergency craniotomy and delayed surgery. These results suggested the patients with IHT had a high sympathetic tone before emergency craniotomy A sudden reduction in sympathetic tone after surgical decompression of the brain might cause IHT. We concluded that an important factor in the occurrence of IHT was not only the injury severity, but also the balance between sympathetic and parasympathetic activity before decompression surgery.     

Significance of post-exercise increment of urinary bicarbonate and pH in subjects loaded with submaximal cycling exercise

We studied the changes in urinary bicarbonate, urinary pH and some physical parameters such as minute ventilation (VE), oxygen consumption (VO2), respiratory carbon dioxide (VCO2), heart rate, blood pressure, and blood lactate, before and after the submaximal exercise. Six male subjects aged 28-33 years were involved in the study. They performed the incremental exercise test using a bicycle ergometer until exhaustion. Levels of VE, VO2, VCO2, heart rate, and blood pressure increased continuously with an increase in cycling intensity. These parameters markedly decreased and reached the baseline levels within 5-10 minutes after the termination of exercise. According to an increase in cycling intensity, blood lactate increased continuously during exercise, but after termination of exercise the return of lactate to the baseline level was markedly retarded. Urinary bicarbonate and pH were within the range of those at 0 time (baseline levels) from the beginning until 30 minutes after the exercise. However, they began to increase abruptly about 30 minutes after the exercise, and continued to increase extensively for 2 hours thereafter. Such marked increase in urinary bicarbonate and pH seemed to be correlated with the aerobic metabolism of lactate in the muscles, liver, and kidney, finally producing CO2. It was also suggested that the measurement of urinary bicarbonate and pH may be useful for the estimation of physiological changes in the body after submaximal incremental cycling exercise loading.