Endovascular surgery for intracranial aneurysm. Histopathological analysis after embolization using balloon or coil

SUMMARY

Recently, endovascular surgery became common approach for management of intracranial aneurysms. Though its efficacy, this approach is still new and under development. Here, we report our clinical experience in patients treated with two methods - balloon or Gugliemi detachable coil. In addition, to understand better the mechanisms underlying postoperative complications, we studied them in histopathological specimens of patients and in a model of experimental aneurysm. From our data we conclude that choice of appropriate therapeutic method should respect specific conditions of patients as well as of facility. Careful postoperative studies including examination of intravascular surface by endovascular scope examination would be useful for prediction of possible complications.

IGF-I gene transfer by electroporation promotes regeneration in a muscle injury model

The goal of this study was to determine whether insulin-like growth factor-I (IGF-I) gene delivery by electroporation promotes repair after muscle injury. An injury-repair model was created using mice in which a hamstring muscle was cut and sutured. A total of 50 microg of IGF-I DNA or green fluorescent protein (GFP) DNA (both in pCAGGS) was injected into the lesion and introduced into muscle cells by electrostimulation using an electric pulse generator. The number of regenerating muscle fibers in the IGF-I DNA group was significantly more than that in the GFP DNA group at 2 weeks after injection. The diameter of regenerating muscle fibers from the IGF-I DNA group was larger than that of the GFP DNA group at 4 weeks after injection. There was no significant difference in the serum IGF-I concentration between the IGF-I DNA group and the GFP DNA group at 1, 2, and 4 weeks after injection. However, muscle IGF-I concentration in the IGF-I DNA injection group was significantly greater than that in the GFP DNA injection group at 2 weeks after injection. These results demonstrated that the effects of enhanced IGF-I production were local and limited to the injected area. The ratio (injected/uninjected; intact) of the amplitude of compound muscle action potentials (CMAP) in the IGF-I DNA injection group was greater than that in the GFP DNA injection group at 4 weeks after injection and of the control group. In conclusion, IGF-I gene transfer by electroporation proved to be a simple, safe, inexpensive, and effective method to promote the regeneration of injured muscles in our injury model.

Mechanism of quadriceps femoris muscle weakness in patients with anterior cruciate ligament reconstruction

The purpose of this study was to investigate gamma loop function in the quadriceps femoris muscle in patients who with less than 6 month-history of anterior cruciate ligament (ACL) reconstruction. For this purpose, we compared the response to vibration stimulation in 10 patients with ACL repair and 12 normal healthy subjects, by measuring the maximal voluntary isometric contraction (MVC) and integrated electromyograms (I-EMG) of the quadriceps muscles. Pre-vibration data were obtained from each subject by measuring the MVC of the knee extension and the I-EMG from the vastus medialis, vastus lateralis, and rectus femoris muscles. Vibration stimulation was applied to the infrapatellar tendons, followed immediately by repeating the MVC and I-EMG recording. Prolonged vibration resulted in a significant decrease of both MVC and I-EMG in the control group. In contrast, the same stimulus failed to elicit changes in ACL-repair group. Our results suggest the presence of abnormal gamma loop function in the quadriceps femoris muscle of patients with ACL repair, which may explain the muscle weakness often described in such patients.

Low-dose ACTH therapy for West syndrome: initial effects and long-term outcome

BACKGROUND

Most Japanese pediatric neurologists attempt other treatments before using adrenocorticotropic hormone (ACTH) therapy for West syndrome (WS), and even then, they use only a low-dose synthetic ACTH to avoid serious adverse effects. In this multi-institutional study, the authors analyzed the initial effects, adverse effects, and long-term outcome in patients treated with low-dose synthetic ACTH in Japan.

METHODS

The medical records of 138 patients with WS, who were treated with low-dose synthetic ACTH therapy for the first time at the authors' institutions between 1989 and 1998, were analyzed.

RESULTS

At the end of ACTH therapy, excellent effect on seizures was noted in 106 of 138 (76%) patients, good effect in 23 (17%), and poor effect in 9 (7%). Initial effects on EEG were excellent in 53 of 138 (38%) patients, good in 76 (55%), and poor in 9 (7%). As for seizure prognosis at the time of follow-up, 51 of 99 (52%) patients were seizure-free, whereas 48 (48%) patients had seizures. Mental outcome was normal in 6 of 98 (6%) patients, mild mental retardation in 16 (16%), moderate mental retardation in 26 (27%), and severe mental retardation in 50 (51%). The initial effects of ACTH on seizures and long-term outcome were not dose dependent (daily dosage 0.005 to 0.032 mg/kg, 0.2 to 1.28 IU/kg; total dosage 0.1 to 0.87 mg/kg, 4 to 34.8 IU/kg). The severity of adverse effects correlated with total dosage of ACTH, and the severity of brain volume loss due to ACTH correlated well with the daily dosage and total dosage of ACTH.

CONCLUSION

Low-dose synthetic ACTH therapy is as effective for the treatment of WS as the higher doses used in previous studies. The dosage of synthetic ACTH used in the treatment of WS can be decreased as much as possible to avoid serious adverse effects.

Stimulation of gene expression of NeuroD-related factor in the mouse brain following pentylenetetrazol-induced seizures

Various genes for transcription factors are induced in neurons involving long-lasting synaptic plasticity that is accompanied by de novo protein synthesis. In this study, we analyzed the gene expression of NeuroD-related factor (NDRF/neuroD2), a neural basic helix-loop-helix transcription factor, in the mouse hippocampus following pentylenetetrazol (PTZ)-induced seizures. Both the levels of mRNA and protein of NDRF were elevated by PTZ injection. In contrast to c-fos, a representative neuronal activation-related immediate-early gene that was induced within 1 h after PTZ administration, induction of the NDRF gene expression reached a maximum level at 7-8 h after PTZ injection and was inhibited by pretreatment with cycloheximide and MK801. In situ hybridization of the mouse hippocampus revealed that NDRF mRNA was significantly induced in the dentate gyrus. During hippocampal development, NDRF transcripts were found to be highly expressed in a juvenile period, when extensive synaptogenesis occurs. Our present results demonstrate that NDRF is a new member of the family of activation-induced transcription factors, whose expression is probably regulated by immediate-early transcription factors. NDRF is thought to be involved in long-lasting neuronal activation.

Taxines from the needles of Taxus wallichiana

A taxine, 5 alpha O-(3'-dimethylamino-3'-phenylpropionyl) taxinine M (1) together with two known compounds 7-O-acetyltaxine A (2) and 2 alpha-acetoxy-2' beta-deacetylaustrospicatine (3) were isolated from the needles of the Himalayan yew, Taxus wallichiana Zucc. Their structures were elucidated on the basis of the NMR spectral data, ESI-MS/MS analysis and chemical methods. Compounds 1 and 3 showed moderate cytotoxic activity against the lung cancer cell line A549 in vitro.

FHIT alterations in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine in rats

Alteration of the FHIT gene was investigated in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl) amine (BHP) in male Wistar rats. Animals at 6 weeks of age were given 2000 p.p.m. of BHP in drinking water for 12 weeks, then maintained without further treatment until killed at the end of week 25. A total of 25 lung adenocarcinomas were obtained and total RNAs were extracted from each for assessment of aberrant transcription of the FHIT gene by reverse transcription (RT)-polymerase chain reaction (PCR) analysis. Aberrant transcripts were detected in 15 adenocarcinomas (60%) as absence in the regions of nucleotides (nt) -9 to 279, -98 to 279, -98 to 348 or -98 to 447. Genomic DNAs were also extracted from all 25 adenocarcinomas and exons 5-9 were examined for mutations, using PCR-single strand conformation polymorphism (SSCP) analysis and sequencing. A mutation was detected in only one adenocarcinoma (4%), an ACC to ATC (Thr to IIe) transition at codon 76. Southern blot analysis of eight tumors did not show any evidence of gross rearrangement or deletion of the FHIT gene. Western blot analysis revealed reduced expression of Fhit protein in six out of 10 adenocarcinomas (60%). These results suggest that alteration of the FHIT gene may be involved in the development of lung adenocarcinomas induced by BHP in rats.

Decreased expression of Bcl-x protein during hepatocarcinogenesis induced exogenously and endogenously in rats

Dysregulations of apoptosis have been widely recognized as important events in multi-stage carcinogenesis. Bcl-x, a member of the Bcl-2 family, is known to act as a regulator of apoptosis. The present study was conducted to assess the role of altered Bcl-x protein expression in exogenous and endogenous hepatocarcinogenesis in rats. In the short-term exogenous models, male Fischer 344 rats, 6 weeks old, were given a single intraperitoneal injection of diethylnitrosamine (DEN) at a dose of 200 mg / kg body weight, partially hepatectomized at the end of week 3, administered phenobarbital at a concentration of 0.05% from the end of week 2 for 6 weeks, and sacrificed. In the livers, glutathione S-transferase (GST-P)-positive, putative preneoplastic lesions were induced, and Bcl-x protein expression was decreased in 24.7% of such lesions. The incidence of GST-P-positive lesions with decreased Bcl-x increased depending on the size of the lesions; 18.9%, 32.4% and 86.5% in the lesions smaller than 0.03, between 0.03 and 0.3, and larger than 0.3 mm(2), respectively. In GST-P-positive lesions larger than 0.3 mm(2), both apoptosis induction and cell proliferation activity were enhanced when Bcl-x protein expression was decreased. In the long-term exogenous models, rats were given 10 mg / kg of DEN, partially hepatectomized 4 h after treatment, administered 0.5 mg / kg of colchicine at the end of days 1 and 3, subjected to a selection procedure, and sacrificed at the end of week 45. Hepatocellular carcinomas were induced with the decreased Bcl-x protein expression. In the endogenous model, rats were fed a choline-deficient, L-amino acid-defined diet for 16 or 80 weeks and sacrificed. Bcl-x protein expression was decreased both in GST-P-positive lesions and hepatocellular carcinoma. These results suggest that this decrease of Bcl-x protein might serve as an indicator of the advanced form of preneoplastic lesions, and that this decrease could also be associated with a potential to progress into carcinoma in both exogenous and endogenous hepatocarcinogenesis of rats.

Promoter structure and gene expression of the mouse inositol 1,4,5-trisphosphate receptor type 3 gene

Inositol 1,4,5-trisphosphate receptor type 3 (IP(3)R3) is a ubiquitously expressed IP(3)R gene in the IP(3)R gene family. We identified an upstream region of the mouse IP(3)R3 genomic DNA. Transcription start points for the IP(3)R3 gene were found to be located mainly at four sites between nucleotide position -325 and -285 relative to the first ATG codon. The major start point was mapped around -325. Transcription promotion ability was detected between -325 and -285 in an IP(3)R3 proximal promoter sequence. The promoter had no TATA-box but was highly GC-rich and contained two putative Sp1-binding sites. There was no sequence similarity between promoter regions of IP(3)R3 and IP(3)R2, another ubiquitous gene, except for GC-boxes. By using a series of 5'-truncation versions and a transient luciferase assay, we detected multiple common and cell-type-dependent regulatory regions within the distal promoter sequence downstream from -4.0 kb that function positively or negatively. The IP(3)R3 gene was highly transcribed in the kidney, spleen, heart, and skeletal muscle, and this tissue distribution pattern was nearly complementary to that of IP(3)R2. We found that IP(3)R3 gene expression was repressed in retinoic acid-treated and neural differentiated P19 mouse embryonic carcinoma cells.