Aneurysms of the anterior communicating artery and subclavian artery in association with congenital absence of unilateral internal carotid artery]

We encountered a rare case of unilateral internal carotid arterial defect complicated with anterior communicating aneurysm and subclavian artery aneurysm. The patient was a 56-year-old man in whom cerebral angiography and 3D-CTA revealed defects in the right internal carotid artery and the right carotid canal, and an unruptured aneurysm in the anterior communicating artery. In addition, the patient was also found to have an unruptured aneurysm in the right subclavian artery. As both the aneurysms were considered to have a high risk of rupture and such subclavian aneurysms were likely to cause an embolism, radical surgery was performed for each aneurysm. The postoperative course was uneventful, and the patient was discharged without ambulatory limitations. Although the defect in the internal carotid artery is a relatively rare vascular deformity, the incidence of cerebral aneurysm is about 30% in such cases due to the marked hemodynamic stress involved. On the other hand, there have been only two previous case reports of internal carotid arterial defect complicated with a subclavian aneurysm. Moreover, there have been no previous reports of internal carotid arterial defect complicated with both an intracranial aneurysm and a subclavian aneurysm, as observed in the present case. Thus, this case was very rare and is reported here.     

Development of a new wound dressing with antimicrobial delivery capability

A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.     

Prolonged but not acute fluoxetine administration produces its inhibitory effect on hippocampal seizures in rats

This study assessed the effects of acute as well as long-term administration of fluoxetine, a selective serotonin (5-HT) reuptake inhibitor with anti-depressant properties, on hippocampal (HIP) seizures elicited by electrical stimulation in rats. The fluoxetine effect on HIP seizures was also assessed following long-term treatment with gepirone, a 5-HT_1A receptor agonist. Acute single administration of fluoxetine (1, 10 mg/kg; IP) was found to produce no significant effect on HIP seizure activity. Following daily IP administration of fluoxetine (10 mg/kg per day) or gepirone (10 mg/kg per day) for 21 days, animals were given a 7-day drug-free period and then challenged with an acute dose of 10 mg/kg fluoxetine. These treatment regimens resulted in a significantly increased afterdischarge threshold of HIP seizures in response to acute fluoxetine administration. The inhibitory effect of fluoxetine, however, was not present 4 weeks after long-term treatment with either fluoxetine or gepirone. The present results indicate that long-term treatment with these compounds enhances the antiepileptic effect of subsequent fluoxetine administration on the generation of HIP seizures. This effect is possibly related to the well-demonstrated evidence that fluoxetine and gepirone, on long-term treatment, facilitate net 5-HT neurotransmission through desensitization of presynaptic 5-HT autoreceptors.     

ENDOSCOPIC SUBMUCOSAL DISSECTION FOR RECURRENT GASTRIC TUMORS

Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.     

Lipid analysis of normal dermis and hypertrophic scars

Hypertrophic scars (HS) are a consequence of abnormal wound healing. We examined fatty acids that are contained within, and participate in, every reaction through the membrane; then, we analyzed the percentage composition of the fatty acids in deepithelialized normal dermis (ND) and HS. In vivo HS samples were obtained from six patients undergoing surgical excision, and ND samples from five patients undergoing skin grafting surgery for excess. In vitro, cultured fibroblasts from HS and ND were also analyzed. The percentage composition of fatty acids extracted from all the samples was analyzed. In vivo, arachidonic acid (20:4) was significantly more abundant in HS than in ND, in the phospholipids from both whole tissue and cell membranes. In vitro, there were no significant differences among ND, HS, and 10% fetal calf serum. The results suggest that HS formation does not necessarily involve simple excess of 20:4; however, there are considerable differences in the percentage composition of 20:4 between ND and HS. Arachidonic acid probably participates in the formation and maintenance of HS, whereas in vitro cultured fibroblasts are affected largely by fetal calf serum.     

Imaging of a large collection of human embryo using a super-parallel MR microscope.

Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology.     

Endogenous bone-marrow-derived stem cells contribute only a small proportion of regenerated myocardium in the acute infarction model.

BACKGROUND: Our recent study showed that granulocyte-colony stimulating factor (G-CSF) promoted bone-marrow cells (BMC) to migrate into the infarcted heart and that they differentiated into cardiomyocytes. However, we still do not know to what degree bone-marrow-derived cardiomyocytes contribute to myocardial regeneration after injury. In this study, we verified the proportional contribution of cells from bone marrow (BM) and from non-bone marrow (n-BM) in regenerating neomyocardium after myocardial infarction. METHODS: Eight C57BL/6 mice were irradiated (900 cGy), and green fluorescent protein (GFP) mouse-derived BMCs (GFP-BMC, 1 x 10(6) cells) were injected. Four weeks later, the left descending coronary artery was ligated. Recombinant human G-CSF (200 microg/kg/day, 8 days) was injected. At 4 weeks after ligation, hearts were fixed for histology. We calculated the proportions of cardiomyocytes derived from BM and n-BM after taking the chimeric rate into consideration. RESULTS: The chimeric rate was 54.6% +/- 5.9%. At the infarcted border area, the total cell number was 1000.3 +/- 56.5/mm(2), and mobilized BM-derived GFP-BMC was 103.3 +/- 13.1/mm(2). After compensation with the chimeric rate, we found BM-derived troponin I-positive cells at 23.9 +/- 4.1/mm(2), nestin-positive cells at 12.9 +/- 2.6/mm(2), and Ki67-positive cells at 18.3 +/- 2.6/mm(2), respectively. We found significant differences in the contribution of troponin I-(6.7% +/- 1.7% vs 93.3% +/- 1.7%), nestin- (2.4 +/- 0.5 vs 97.6 +/- 0.5), and Ki67-positive (3.9 +/- 1.0 vs 96.1 +/- 1.0) cells derived from BM and n-BM. CONCLUSIONS: Bone marrow was one of the origins of regenerated cardiomyocytes; however, the contribution of cells from BM was very small compared with those of n-BM origin in the infarction model.     

Clinical and immunological studies on patients with Graves' disease preoperatively treated with corticosteroids and iodides

The purpose of this study was to evaluate the acute effects of corticosteroid and iodide preoperative therapy in patients with Graves' disease in terms of thyroid function and immunological parameters. The above combination was prescribed for 4 patients who had experienced severe side effects from antithyroid drugs (ATD) in order to reduce the possibility of post-thyroidectomy thyroid storm. Corticosteroids were employed daily for four days, and iodides were given daily for two weeks prior to thyroidectomy. The free T₃ values decreased rapidly to euthyroid levels following the administration of both drugs, although the free T₄ values were still much higher than normal in 3 of the 4 patients at the time of surgery. By comparison, 3 of 8 patients treated with ATD also had thyroid hormone levels above normal. Studies of lymphocyte subsets revealed that the percentage of helper T cells was significantly less in the corticosteroidiodide treatment group than in the control and ATD groups. It is thus possible that postoperative thyroid storm might be prevented through corticosteroid-iodide therapy by virtue of the reduction of free T₃ values to within the normal range by the time of surgery. The acute suppression of helper T cells was another result of this form of therapy observed.     

Uptake and biotransformation of sevof lurane in humans: A comparative study of sevof lurane with halothane, enflurane, and isoflurane

Study Objective: To compare the volatile anesthetic sevoflurane with halothane, enfurane, and isof urane on the uptake and biotransformation in humans.

Design: Prospective pharmacokinetic study of sevofurane administration in human subjects.

Setting: Inpatient surgery clinic at a university medical center.

Patients: Thirty-two Japanese patients, free of systemic diseases, undergoing minor elective surgery with endotracheal general anesthesia.

Interventions: The patients were assigned randomly to one of four groups: halothane, enflurane, isofurane, or sevofurane. One of the four volatile anesthetics being investigated [equivalent to 1.1 minimum alveolar concentration (MAC): halothane, 0.85%; enfurane, 1.85%; isofurane, 1.27%; and sevofurane, 1.88%; in inspired concentrations throughout the first hour of anesthesia] was administered for 60 minutes.

Measurements and Main Results: In all patients, serum and urinary fluoride concentrations were measured. The concentrations of all gases were measured separately with a mass spectrometer. The cumulative uptake of each anesthetic agent during a certain period was calculated as an integration of the uptake rate per minute. The results for one-hour inhalation of sevofurane (1.1 MAC) showed an uptake (corrected for body surface area and MAC) of 490 ml/m²/MAC and estimated degradation rate of 3.3%. For purposes of comparison, similar studies of halothane (uptake, 653 ml/m²/MAC; degradation rate 15.7%), enfurane (1150 ml/m²/MAC; 1.3%), and isofurane (439 ml/m²/MAC; 0.6%) were also conducted. Sevofurane had a peak serum inorganic fluoride concentration of 19.3 μmol/L, and no abnormality in hepatic or renal functions was observed in any of the subjects during the two weeks postoperatively.

Conclusions: Accurate determinations of uptake and degradation rate for sevoflurane and three other volatile anesthetics in Japanese patients were obtained. These findings have established that, despite its relatively large MAC *1.71%), sevoflurane has a small uptake due to its low solubility. However, the degradation rade was shown to be as high as 3.3%, resulting in a higher serum fluoride concentration than seen after administration of isoflurane, halothane, and (possibly) enflurane.