PubMed Health⌕ Search

Biomedical subjects

Isao Hasegawa

Publications and source records attributed to Isao Hasegawa.

6 recordsLinked to original sources
PubMed2006

Ambroxol-induced modification of ion transport in human airway Calu-3 epithelia.

Ambroxol is often used as a mucolytic agent in various lung diseases. However, it is unclear how ambroxol acts on bronchial epithelial cells. To clarify the action of ambroxol, we studied the effects of ambroxol on the ion transport in human Calu-3 cells, a human submucosal serous cell line, measuring the transepithelial short-circuit current and conductance across monolayers of Calu-3 cells. Ambroxol of 100 microM diminished the terbutaline (a beta2-adrenergic agonist)-stimulated Cl-/HCO3(-)-dependent secretion without any decreases in the conductance of cystic fibrosis transmembrane conductance regulator (CFTR) channel locating on the apical membrane. On the other hand, under the basal (unstimulated) condition ambroxol increased the Cl(-)-dependent secretion with no significant change in the apical CFTR channel conductance and decreased the HCO3- secretion associated with a decrease in the apical CFTR channel conductance. Ambroxol had no major action on the epithelial Na+ channel (ENaC) or the ENaC-mediated Na+ absorption. These results indicate that in Calu-3 cells: (1) under the basal (unstimulated) condition ambroxol increases Cl- secretion by stimulating the entry step of Cl- and decreases HCO3- secretion by diminishing the activity of the CFTR channel and/or the Na+/HCO3(-)-dependent cotransporter, (2) under the adrenergic agonist-stimulated condition, ambroxol decreases Cl- secretion by acting on the Cl-/HCO3- exchanger, and (3) ambroxol has a more powerful action than the adrenergic agonist on the Cl-/HCO3- exchanger, leading fluid secretion to a moderately stimulated level from a hyper-stimulated level.

Ambroxol↗
PubMed2005

Prognostic factors for ovulatory response with clomiphene citrate in polycystic ovary syndrome.

OBJECTIVE: To evaluate prospectively the prognostic factors for ovulatory responses following clomiphene citrate (CC) administration in polycystic ovary syndrome (PCOS). STUDY DESIGN: Fifty-nine infertile patients with a diagnosis of PCOS were recruited. Ovulation was induced using 100 mg/day CC administered daily from days 5 to 9 of the cycle. Endocrine and metabolic parameters between responder and non-responder groups were analyzed. RESULTS: For a 75-g fasting glucose load (75-g OGTT), blood glucose levels at 60 and 120 min, the area under the curve (AUC) and blood insulin levels at 120 min in the non-responder group (n=25) were significantly higher than those in the responder group (n=34), although the measurements of fasting blood glucose and insulin were not significantly different between the two groups. In the receiver operating characteristic curves, the most appropriate cutoff point was 120 mg/dl for the blood glucose level at 120 min and 9000 for the blood glucose x insulin level at 120 min. There were no significant differences in the clinical characteristics or in the endocrine and metabolic parameters between conceived (n=9) and non-conceived groups (n=21). CONCLUSION: The levels of blood glucose and blood glucose x insulin at 120 min after 75-g OGTT could be good biochemical markers of CC resistance in PCOS. No predictors of conception following CC therapy were identified by this study.

Administration, Oral↗
PubMed2005

[A case of non-mucin-producing papillary adenocarcinoma with a 19-year clinical history before operation].

A 73-year-old woman was admitted to our hospital for investigation of an abnormal shadow in the right upper lung field. Every year she had a medical check up since 1983 and the abnormal shadow was repeatedly pointed out However, she had not undergone a detailed examination. When she had a medical check up in July 2001, the shadow slightly increased compared with the previous chest film. Chest CT showed the mass with a pleural indentation in the right S3a, measuring 4 x 4 cm in size. Despite examinations including bronchoscopy we could not make a definitive diagnosis. After we explained the situation to her, she decided to have an operation. The biopsy during the operation revealed adenocarcinoma and right upper lobectomy with nodal dissection was performed. The ultimate diagnosis was non-mucin-producing papillary adenocarcinoma. This stage IB case was pT2N0M0. We reported this case because it was a rare slow-growing papillary adenocarcinoma that did not produce mucin and had a 19-year clinical history before operation.

Adenocarcinoma, Papillary↗
PubMed2004

Functional magnetic resonance imaging of macaque monkeys performing visually guided saccade tasks: comparison of cortical eye fields with humans.

The frontal and parietal eye fields serve as functional landmarks of the primate brain, although their correspondences between humans and macaque monkeys remain unclear. We conducted fMRI at 4.7 T in monkeys performing visually-guided saccade tasks and compared brain activations with those in humans using identical paradigms. Among multiple parietal activations, the dorsal lateral intraparietal area in monkeys and an area in the posterior superior parietal lobule in humans exhibited the highest selectivity to saccade directions. In the frontal cortex, the selectivity was highest at the junction of the precentral and superior frontal sulci in humans and in the frontal eye field (FEF) in monkeys. BOLD activation peaks were also found in premotor areas (BA6) in monkeys, which suggests that the apparent discrepancy in location between putative human FEF (BA6, suggested by imaging studies) and monkey FEF (BA8, identified by microstimulation studies) partly arose from methodological differences.

Analysis of Variance↗
PubMed2003

Prefrontal neuronal activity encodes spatial target representations sequentially updated after nonspatial target-shift cues.

We examined prefrontal neuronal activity while monkeys performed a sequential target-shift task, in which, after a positional cue indicated the initial saccade target among 8 peripheral positions, the monkeys were required to internally shift the target by one position on every flash of a target-shift cue. The target-shift cue appeared in the center 0 to 3 times within a single trial and was always the same in shape, size, and color. We found selective neuronal activity related to the target position: when the target-shift cue implied the target shift to particular peripheral positions, neurons exhibited early-dominant and late-dominant activity during the following delay period. The early-dominant target-selective activity emerged early in the delay just after the presentation of the target-shift cue, whereas the late-dominant activity gradually built up toward the end of the delay. Because the target-shift cue was not related to any specific target location, the early-dominant target-selective activity could not be a mere visual response to the target-shift cue. We suggest that the early-dominant activity reflects the transitory representation for the saccade target that was triggered by the nonspatial target-shift cue, whereas the late-dominant activity reflects the target representation in the spatial working memory or the preparatory set for the possible impending saccade, being repeatedly updated during sequential target shifts.

Animals↗