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11.
Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies. 相似文献
12.
M Nakanishi Y Demura S Mizuno S Ameshima Y Chiba I Miyamori H Itoh M Kitaichi T Ishizaki 《The European respiratory journal》2007,29(3):453-461
High-resolution computed tomography (HRCT) findings in patients with respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) are varied and nonspecific. There is no known report of changes in HRCT findings and respiratory function test results for RB-ILD patients following the cessation of smoking. Five patients with RB-ILD, confirmed by surgical lung biopsy, were retrospectively studied. Each stopped cigarette smoking and did not receive corticosteroid therapy after diagnosis. The clinical symptoms, respiratory function test results and HRCT findings obtained at the final observation were compared with those from the time of diagnosis. Ground-glass opacity and centrilobular nodules corresponding to pathological respiratory bronchiolitis, as well as intralobular fine linear-reticular opacity corresponding to fibrosis involving the subpleural alveolar septa, showed computed tomography-pathological correlations. Both clinical symptoms and the diffusing capacity of the lungs for carbon monoxide improved significantly following smoking cessation, as did ground-glass opacity and centrilobular nodules seen during the initial HRCT examination. Centrilobular nodules and ground-glass opacity, which are the main features of high-resolution computed tomography of respiratory bronchiolitis-associated interstitial lung disease patients and represent pathological respiratory bronchiolitis, can be improved by smoking cessation. The diffusing capacity of the lung for carbon monoxide in respiratory function tests can be also improved. 相似文献
13.
The incidence of late infection after cranioplasty was studied in 130 patients with 133 cranioplasties. The materials used were prefabricated resin in 62 cases, autogenic bone in 38, intraoperatively fashioned resin in 25, and vitallium in eight. Six infections were documented, for an infection rate of 4.5%. In addition to these six cases, we studied eight patients with infections who had undergone cranioplasty elsewhere but had the infected plates removed in our hospitals. Among the 14 cases of infection, the intervals between cranioplasty and plate removal were 3 to 43 months (average, 10.5 months). The eight patients referred from other hospitals had a significantly shorter average interval between external decompression and cranioplasty than did patients who did not develop infection (2.6 versus 6.7 months; p less than 0.005). Systemic signs were mild despite obvious local signs of infection. Of the 11 first infections, nine (82%) were associated with discharge of pus from a fistula; in these cases a galeal suture had become infected apparently through scratching by the patients. In contrast, in the three patients who had had a previous infection, the second infection manifested as subgaleal and epidural empyema or meningitis without a fistula or pus discharge. Nine infections (69%) were due to Staphylococcus. All but two patients required removal of the infected plates. One recovered with conservative therapy and one died of meningitis, giving a mortality rate of 0.8%. No matter how mild the systemic signs, late infection warrants surgical debridement and plate removal. The risk factors for late infection of cranioplasty are discussed. 相似文献
14.
Tatsurou Tanaka Yasuhiro Morimoto Hiroshi Takano Kazuhiro Tominaga Shinji Kito Sachiko Okabe Tetsu Takahashi Jin-ichi Fukuda Takeshi Ohba 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(5):609-613
OBJECTIVE: To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences. METHODS: The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography. RESULTS: In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed. CONCLUSIONS: Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium. 相似文献
15.
Isolated rupture of radial collateral ligament of the small finger DIP joint is a rare injury. We treated this lesion using a bone suture anchor with excellent results. 相似文献
16.
A 40-year-old man was hospitalized for tremor of the right upper limb, gait disturbance and dysarthria. His course of development had been normal until the age of 14, when difficulties in speaking and walking, and tremor of the upper limb became evident following an episode of fever. His symptoms have been gradually worsening for the past 25 years. His elder sister showed similar clinical symptoms and progressive course of illness. The patient showed no indication of mental retardation. Neurological examination showed dysarthria, slow dyskinetic movement of the tongue, dystonic posture of the left hand, tremor of irregular frequency of the right upper limb, diminished tendon reflex, positive Romberg's sign, diminished vibratory and position sense in the lower limbs and pyramidal signs. Cystometry indicated defective voiding of the bladder. Magnetic resonance imaging of the brain showed bilateral atrophy of the putamina, globus pallidus, caudate nuclei and substantia nigra. MRI showed similar findings in her sister. By electrophysiological and pathological examination, disorders of other systems were evident, such as upper motor neurons, and sensory tract. GM1 and GM2 gangliosidosis appeared the most likely diagnosis, but were ruled out on the basis of the result of lysozomal enzyme assay and rectal biopsy. The present patient's condition may possibly be the result of an unknown metabolic disorder, or a new disease entity affecting various components of the nervous system. 相似文献
17.
Yoshimasa Sakamoto Kazuhiro Hashimoto Hiroshi Okuyama Shinichi Ishii Takahiro Inoue Katsushi Kinouchi Takayuki Abe 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(9):465-469
Objective The objective of the present study was to compare long-term results of single aortic valve replacement (AVR) with mechanical
(St. Jude Medical valves: standard) and biologic (the Carpentier-Edwards pericardial) prostheses. Method: Between 1995 and 2002, 95 patients who underwent single AVR with mechanical (n=46) or biologic (n=49) prostheses were enrolled
in this study. The mean age at the operation was 54.0±9.6 years (range: 20 to 69 years) with the mechanical and 68.8±7.1 years
(range: 44 to 85 years) with the biologic prosthesis. Results: The 9-year actuarial survival rate, which was calculated by taking perioperative mortality into account, was 90.3±4.6% for
patients with mechanical valves and 87.6 ±4.8% for patients with bioprostheses, with no difference between the two groups
(p=0.342). The 9-year freedom rate from thromboembolism, reoperation, endocarditis was 94.8+3.6%, 100% and 97.8 ±2.2% for
patients with mechanical valves and 98.0 ±2.0%, 97.5 ±3.4% and 95.0 ±3.4% for those with bioprostheses, respectively. After
9 years, freedom from cardiac death averaged 97.8% in the group with mechanical valves compared with 95.3% in those with bioprostheses
(p=0.541). Conclusion: We conclude that the mid-term durability of the Carpentier-Edwards pericardial valve in the aortic position for the elderly
is excellent. Nevertheless, the risk of tissue valve reoperation progressively increases with time, and a longer follow-up
may be necessary to provide its value compared with the mechanical valves in a country like Japan with a high life expectancy.
(Jpn J Thorac Cardiovasc Surg 2005; 53:465-469) 相似文献
18.
Yukio Naya Toyofusa Tobe Takahito Suyama Kazuhiro Araki Akira Komiya Hiroyoshi Suzuki Tatsuo Igarashi Tomohiko Ichikawa 《International journal of urology》2007,14(1):17-20
OBJECTIVES: Laparoscopic surgery for kidney treatment is a common procedure. However, the efficacy of this procedure in patients with several comorbidities has not been well investigated. We conducted a retrospective comparison of results of laparoscopic surgery between patients with several comorbidities and patients with no comorbidity to access the efficacy and safety of this procedure. METHODS: The subjects were 20 patients with three or more comorbidities (group A) and 46 patients with less than three comorbidities (group B). These 66 patients were 48 men and 18 women with a mean age of 62.3 years (age range, 24-83 years). The data from these two groups were compared for American Society of Anesthesiology (ASA) physical status score, previous surgical history, duration of surgery, estimated blood loss, tumor size, complications during and after surgery, conversion rates, time to oral intake, and length of hospital stay. RESULTS: The initial ASA score and age were significantly higher for the patients with comorbidities (P < 0.0001, P = 0.0008, respectively). All other variables before, during, and after surgery were similar for both laparoscopic groups. However, the incidence of atelectasis of laparoscopy was higher than that of open surgery. CONCLUSIONS: Laparoscopic nephrectomy for patients with comorbidities is safe and minimally invasive. Further investigation to prevent atelectasis is necessary. 相似文献
19.
Susumu Kusunoki Atsuro Chiba Seiji Hitoshi Hajime Takizawa Ichiro Kanazawa 《Muscle & nerve》1995,18(4):409-413
Four of 82 patients with Guillain-Barré syndrome (GBS) and 1 of 12 with multifocal motor neuropathy (MMN), who previously had had Mycoplasma pneumoniae infections, had serum antibody to galactocerebroside (Gal-C). Two patients with GBS without mycoplasma infection also had anti-Gal-C antibody, whereas none of the normal or the disease controls had it. As Gal-C is a major glycolipid antigen in myelin, anti-Gal-C antibody may function in the pathogenesis of autoimmune demyelinative neuropathies. Mycoplasma pneumoniae appears to be an important preceding infectious agent in autoimmune neuropathies with anti-Gal-C antibody. © 1995 John Wiley & Sons, Inc. 相似文献
20.
Masatoshi Chiba Takashi Shigihara Seishi Echigo Teiichi Teshima 《Journal of bone and mineral metabolism》1990,8(3):24-29
Summary In this study, we examined histologically the effect of a bone morphogenetic protein (BMP) derived from bovine tooth on the
periosteum. Supraperiosteal injection of crude BMP into femurs of Wistar rats (28 day old) resulted in periosteal cell proliferation
with subsequent bone and cartilage formation. Moreover, proliferating periosteal cells migrated into injected BMP, and formed
both cartilage and bone. These observations show that exogenous BMP stimulates mesenchymal cells of the periosteum to proliferate
and differentiate into osteoblasts, and therefore BMP may be one of factors which are involved in differentiation of osteoblasts
in the periosteum. 相似文献