Biomedical subjects

Yoshihiro Kobayashi

Publications and source records attributed to Yoshihiro Kobayashi.

At least 19 recordsLinked to original sources

PubMed2006

Mutation of epidermal growth factor receptor gene in adenosquamous carcinoma of the lung.

We have investigated 26 adenosquamous lung cancer tissues and found that four EGFR mutations were mainly in female and non-smoker lung cancer. However, EGFR mutation at kinase domain was exclusive with K-ras mutation. However, smoking and gender status could affect the occurrence of EGFR mutation. There was no difference in EGFR mutation status if analysis was performed in never smoker female subgroup.

Aged↗

PubMed2006

PIK3CA mutation status in Japanese lung cancer patients.

Somatic mutations of the PIK3CA (phosphatidylinostitol 3-kinase catalytic subunit) gene have been found in human cancer patients. Previous reports suggested that about 4% of lung cancers harbored PIK3CA gene mutations. However, the clinico-pathological background for PIK3CA gene mutations has not yet been investigated in lung cancer. We have genotyped the PIK3CA gene in Japanese lung cancer patients. The study included 235 lung cancer cases surgically removed in Nagoya City University Hospital. The two PIK3CA mutation hot spots (exon 9 and exon 20) were analyzed by real time polymerase chain reaction (PCR)-based assay. The data were confirmed by direct sequencing. In exon 9, somatic mutation was found in eight patients (3.4%). The mutation included three E542K (G1624A), three E545K (G1633A), one E542Q (G1624C), and one Q546K (C1636A). However, in exon 20, there was no mutation in our lung cancer patients. PIK3CA mutations were not correlated with gender (women versus men, p=0.4162), age (< or =60 versus >60, p=0.8027), or smoking status of the lung cancers (never versus smoker, p=0.5666). PIK3CA mutation incidence was significantly lower in adenocarcinoma (2/135, 1.5%) than in squamous cell carcinoma (5/77, 6.5%, p=0.0495). Among eight patients with a PIK3CA mutation, three patients also harbored an EGFR somatic mutation. PIK3CA gene mutations were rare in lung cancer; rarer in adenocarcinoma. Further functional analyses of the PIK3CA mutations are warranted to study if they could be the target of therapy for the lung cancer.

Adenocarcinoma↗

PubMed2006

L858R EGFR mutation status correlated with clinico-pathological features of Japanese lung cancer.

Somatic mutations of the epidermal growth factor receptor (EGFR) gene were found in about 25-40% of Japanese lung cancer patients. These mutations are associated with clinical and radiographic responses to EGFR tyrosine kinase inhibitors. Most common mutation are arginine for leucine substitution at amino acid 858 (L858R) and exon 19 deletions, especially deletion type 1 mutation. We investigated these EGFR mutation statuses in 575 surgically treated non-small cell lung cancer (NSCLC) cases. Three-hundred and sixty-two adenocarcinoma cases were included. The presence or absence of EGFR mutations of kinase domains was analyzed by genotyping analysis (TaqMan assay; n=386, and LightCycler assay; n=98) and sequences (n=91). EGFR mutations (CTG; CGG; L858R) were found from 63 of 575 lung cancer patients. We also detected the deletion 1a type mutations (2235-2249 del GGAATTAAGAGAAGC) from 39 patients and deletion 1b type mutations (2236-2250 del GAATTAAGAGAAGCA) from 15 patients in exon 19. These mutation statuses were significantly correlated with gender, smoking status (never smoker versus smoker), and pathological subtypes (adenocarcinoma versus non-adenocarcinoma). L858R mutation (p<0.0001), but not deletion 1 type mutation (p=0.0665), was correlated with differentiation status (well versus moderately or poorly) of lung cancers. L858R mutation ratio was significantly higher in non-smoker (p=0.0496) and adenocaicinoma (p=0.0136) when compared to deletion 1 type mutations. The EGFR mutation status, especially L858R mutation might be correlated with the clinico-pathological features related to good response to gefitinib, such as gender, smoking history, and pathological subtypes of Japanese lung cancers.

Adenocarcinoma↗

PubMed2006

Expression and mutation statuses of epidermal growth factor receptor in thymic epithelial tumors.

BACKGROUND: Epidermal growth factor receptor (EGFR) gene mutations have been reported to correlate with the sensitivity to the tyrosine kinase inhibitor treatment for advanced lung cancers. Since several reports have shown that invasive thymoma overexpress the EGFR protein, we examined the EGFR expression and mutation statuses in thymoma and thymic carcinoma tissues. METHODS: EGFR mutation statuses from 99 thymic epithelial tumor samples were evaluated by a rapid and sensitive TaqMan assay using Applied Biosysytems 7500 real-time PCR system. Probes were designed according to the 13 different EGFR mutations reported previously in lung cancers. A total of 38 thymoma samples were directly sequenced for the EGFR gene. Protein expressions were evaluated for 56 thymic epithelial tumors by immunohistochemistry. RESULTS: EGFR gene mutations were not detected in any of the thymoma and thymic cancer samples using TaqMan PCR assay. Of the 38 samples 3 showed a heterozygous silent mutation without changes in the protein, a G to A transition at the nucleotide 2361 in exon 18. EGFR expression was significantly higher in invasive thymomas (stages III-IV, 15/19 were positive) than in early stage thymomas (stages I-II, 7/33 were positive) (P < 0.0001). All four carcinomas and all seven B3 thymomas showed EGFR positive staining. CONCLUSIONS: Although EGFR mutation at the tyrosine kinase domain is unlikely to be a therapeutic target for thymoma, the information about EGFR expression would contribute to the further identification of the therapeutic target for advanced thymomas.

Adult↗

PubMed2006

Preoperative steroid pulse therapy for invasive thymoma: clinical experience and mechanism of action.

BACKGROUND: Glucocorticoid was used in thymomas. The purpose of the study was to evaluate the efficacy of intravenous high-dose glucocorticoid (steroid pulse) therapy in patients with previously untreated advanced thymoma. Causes were also sought for a possible underlying mechanism of the effect of steroid on thymoma. METHODS: Seventeen patients with invasive thymoma who had not received previous chemotherapy or radiation therapy were enrolled in the study. All cases were treated with 2 courses of glucocorticoid therapy before surgery. Tumor response was assessed by computed tomography (CT) scan 1 week after the steroid pulse therapy. Lymphocytes associated with thymoma were analyzed for their CD4/CD8 phenotype and glucocorticoid receptor (GR). TdT-mediated dUTP-biotin nick-end labeling (TUNEL) staining was used to analyze the apoptotic lymphocytes and epithelial cells. RESULTS: The overall response rate to the steroid pulse therapy was 47.1% (8 of 17). The reduction in tumor size was most prominent in type B1 thymomas; there were significant differences between type AB and type B1 thymomas (P = .0234) and type B1 and type B3 thymomas (P = .0068). The reduction in tumor size was accompanied with a marked reduction in the CD4+8+ double-positive immature thymocytes that expressed higher levels of glucocorticoid receptor. Apoptotic changes were observed in both neoplastic epithelial cell and lymphocyte components after glucocorticoid therapy. CONCLUSIONS: The efficiency of preoperative steroid pulse therapy in type B1 thymoma was most prominent, which is probably related to the specific effect on GR-rich CD4+8+ double-positive immature lymphocytes, which are abundant in this type of thymoma.

Adult↗

PubMed2006

Epidermal growth factor receptor gene mutation defines distinct subsets among small adenocarcinomas of the lung.

Epidermal growth factor receptor (EGFR) gene mutations are frequently detected in lung cancer, especially in adenocarcinoma, in females, and non-smoking patients. EGFR mutations are closely associated with clinical response to EGFR tyrosine kinase inhibitor. Bronchioloalveolar carcinoma (BAC) appearance is a good predictor of response to this agent. Noguchi et al. subdivided small peripheral adenocarcinoma of the lung into two groups. One group was characterized with tumor cell growth replacing the normal alveolar cells with varying degree of fibrosis (types A-C), and the other shows non-replacing and destructive growth (types D-F). Using probes for the 13 mutations which have been previously described, we have genotyped the EGFR gene status in surgically resected atypical adenomatous hyperplasias (AAH) and small peripheral adenocarcinomas up to 2 cm in diameter using TaqMan PCR assay. In 95 small-sized adenocarcinomas, the EGFR mutations were detected in 37 patients (38.9%), and no mutations were found in five AAHs. In small peripheral adenocarcinomas, EGFR mutations were found 47.1% of types A, B, or C adenocarcinomas; it was less frequent (16%) in Noguchi's types D, E or F adenocarcinomas. These results suggest that type D, F adenocarcinomas are not derived from the less malignant types A-C adenocarcinomas; rather, they have arisen de novo by distinct mechanisms. Although types A and B adenocarcinomas are almost 100% cured by surgery, some type C adenocarcinoma show lymph node metastasis and relapse. EGFR mutation analysis may help identify patients who will respond to treatment with tyrosine kinase inhibitors, e.g., gefitinib.

Adenocarcinoma↗

PubMed2006

A correlation between EGFR gene mutation status and bronchioloalveolar carcinoma features in Japanese patients with adenocarcinoma.

BACKGROUND: The presence of epidermal growth factor receptor (EGFR) mutations in gefitinib-naive lung cancer patients has been reported to be higher in females, in non-smokers, in Japanese, and in adenocarcinoma patients, especially in bronchioloalveolar carcinoma (BAC). To further investigate the prevalence of EGFR mutations in relation to pathological factors, we evaluated EGFR mutations in series of Japanese adenocarcinoma patients who had never been treated with gefitinib. METHODS: In the previous studies, we examined mutation status in the tyrosine kinase domain of EGFR, exon18 through exon21, in 112 primary lung adenocarcinoma samples. Using these data, adenocarcinomas were histologically classified according to the presence or absence of bronchioloalveolar components. RESULTS: Among 112 patients, 48 had adenocarcinoma with BAC components. Those with adenocarcinomas with BAC components had higher frequency of EGFR mutation (28/48, 58%) than those with non-BAC adenocarcinoma (24/64, 37%, P = 0.036). Male patients had the same trend; 12/23 (52%) male patients with adenocarcinoma with BAC components and 10/47 (21%) of those with non-BAC adenocarcinoma had EGFR mutation (P = 0.0135) but there was no correlation between the EGFR mutation status and with/without BAC components in 42 female patients (P = 0.30). Among 11 male non-smokers, patients with adenocarcinoma with BAC components had a tendency to have EGFR mutation more frequently than those with non-BAC adenocarcinoma (P = 0.061). In clear contrast, the frequency of EGFR mutation did not differ significantly between male smoker patients with adenocarcinoma with BAC components and those with non-BAC. Among patients with adenocarcinoma with BAC components, those with adenocarcinoma with EGFR gene mutation had a significantly better 5 year survival than those with adenocarcinoma with wild-type (85.7 versus 46.0%, P = 0.0017). CONCLUSIONS: Adenocarcinomas with BAC components in male non-smokers seem to predict the presence of EGFR mutation. Half of female adenocarcinoma patients with EGFR mutation exhibit adenocarcinomas with non-BAC suggesting a different behavior from those in males. The prognosis of patients with adenocarcinoma with BAC components with EGFR gene mutation is predicted to be better than that of patients with adenocarcinoma with BAC components with wild-type EGFR gene.

Adenocarcinoma↗

PubMed2006

EGFR and erbB2 mutation status in Japanese lung cancer patients.

Much evidence has accumulated that the epidermal growth factor receptor (EGFR) and its family members are strongly implicated in the development and progression of lung cancers. Somatic mutations of the EGFR gene were found in about 25-40% of Japanese lung cancer patients. More recently, erbB2 mutations are found in about 4% of European-derived lung cancer patients. We have investigated EGFR and erbB2 mutation status in 95 surgically treated nonsmall cell lung cancer (NSCLC) cases from Nagoya City University Hospital. Seventy-five adenocarcinoma cases were included. The presence or absence of EGFR and ernB2 mutations of kinase domains were analyzed by reverse transcription polymerase chain reaction (RT-PCR) amplifications and direct sequences. We have also investigated erbB2 mutation status in 27 surgically treated NSCLC cases followed by treatment with gefitinib from Kinki-chuo Chest Medical Center. EGFR mutations (CTG-->CGG; L858R) were found from 14 of 95 lung cancer patients. We also detected the deletion 1a-type mutations from 9 patients and deletion 4-type mutations from 6 patients in exon 19. In exon 20, 4 mutations including 2 novel mutations were found. Total EGFR mutations were present in 35 patients (36.8%). These mutation statuses were significantly correlated with gender (women 73.3% vs. men 20%, p < 0.0001), smoking status (never smoker 69.4% vs. smoker 16.9%, p < 0.0001), pathologic subtypes (adenocarcinoma 45.1% vs. nonadenocarcinoma 12.5%, p = 0.0089) and differentiation status of the lung cancers (well 51% vs. moderately or poorly 18.4%, p = 0.0021). On the other hand, erbB2 mutation was only found from 1 of 95 patients, at exon 20. This patient was female and a never smoker with adenocarcinoma. This 12 nucleotide insertion mutation (2324-2325 ins ATACGTGATGGC) was located in the exon 20 at kinase domain (775-776 ins YVMA). There was no erbB2 mutation in 27 gefitinib-treated NSCLC patients. In total, we have found only 1 erbB2 mutation from 122 (0.8%) Japanese NSCLC patients. There was a significantly higher erbB2 positive (2+/3+) ratio in EGFR mutant patients (13/25, 52.0%) compared to EGFR wild-type patients (10/62, 16.1%; p = 0.0247). The NSCLC specimen with erbB2 mutation showed 1+ immunoreactivity. The EGFR mutation status might correlate with the clinicopathologic features related to good response to gefitinib, such as gender, smoking history and pathologic subtypes of lung cancers. However, erbB2 mutation is rare from Japanese lung cancer and is of limited value for molecular target therapy.

Aged↗

PubMed2006

ACTH-secreting thymic carcinoid associated with multiple endocrine neoplasia type 1.

Thymic carcinoids are classified into three categories: (1) nonsecretory tumors, (2) hormonal secretory tumors, and (3) tumors associated with multiple endocrine neoplasia type 1. We report a rare case with adrenocorticotropic hormone secreting thymic carcinoid with multiple endocrine neoplasia type 1. Radiologic examination showed an anterior mediastinal mass and a parathyroid tumor. Blood analysis revealed high levels of parathyroid hormone and adrenocorticotropic hormone. Urine cortisol and 17-hydroxycorticoids levels were also elevated. Extended thymectomy was performed. Subsequently adjuvant radiation therapy and parathyroid tumor resection were performed. A germline mutation of exon 7 in the multiple endocrine neoplasia type 1 gene was detected and a somatic mutation of exon 9 was demonstrated in the thymic tumor.

ACTH Syndrome, Ectopic↗

PubMed2006

Single-walled carbon nanotube growth from highly activated metal nanoparticles.

We demonstrate that any metal, even gold, silver, and copper, can act as a catalyst for SWCNT synthesis in chemical vapor deposition (CVD). Metal nanoparticles 3 nm or less in diameter, introduced into CVD ambience immediately after heat treatment at 800-950 degrees C in air, produce SWCNTs. The activation method is effective for copper and various noble metals as well as for iron-family elements. This implies that any metal particle may produce SWCNTs when its size becomes 1-3 nm. In other words, carbon atoms can form SWCNTs in a self-assembling fashion on nanoparticles without the specific functions of iron-family elements.

Journal Article↗

PubMed2006

Decreased fragile histidine triad gene messenger RNA expression in lung cancer.

BACKGROUND: The fragile histidine triad (FHIT) gene is located at 3p14.2, a region frequently lost in various tumor types. Lack of FHIT expression has been found to occur frequently in multiple tumor types including lung cancer. We have investigated FHIT messenger RNA (mRNA) levels and other clinicopathologic data, including FHIT and p21 expression in lung cancer. PATIENTS AND METHODS: The study included 97 lung cancer cases. The FHIT mRNA levels were quantified by quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) using LightCycler. RESULTS: The FHIT/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels were decreased in tumor tissues from lung cancer (13.844 +/- 33.047) compared with adjacent nonmalignant lung tissues (195.763 +/- 678.469; P < 0.0001). No significant difference in FHIT/GAPDH mRNA levels was found among age, T status, or lymph node metastasis. The FHIT/GAPDH mRNA level was less in squamous cell carcinoma (0.144 +/- 0.246), a smoking-related cancer, than in adenocarcinoma (0.72 +/- 1.321; P = 0.0355). FHIT/GAPDH mRNA levels were correlated with FHIT protein (P = 0.0139) and p21 protein (P = 0.0484) expression by immunohistochemistry. The prognosis for patients with lung cancer with low FHIT/GAPDH levels (< 0.26; n = 57) was significantly worse than in the patients with high FHIT/GAPDH levels (> 0.26; n = 40; log-rank test, P = 0.0404). CONCLUSION: Using the LightCycler RT-PCR assay, decreased FHIT gene expression might occur early and play an important role in lung tumorigenesis and also correlate with the prognosis of lung cancer. However, further studies are needed to confirm the impact of FHIT in the biologic behavior of the tumor.

Acid Anhydride Hydrolases↗

PubMed2006

Decreased kallikrein 11 messenger RNA expression in lung cancer.

BACKGROUND: Human kallikrein 11 (hK11) is a putative serine protease of the human kallikrein gene family. A recently developed method for measuring hK11 suggested that the hK11 level was an indicator of favorable prognosis in patients with ovarian cancer. We have investigated hK11 messenger RNA (mRNA) levels in lung cancer. PATIENTS AND METHODS: This study included 64 lung cancer cases. The hK11 mRNA levels were quantified by real-time reverse-transcriptase polymerase chain reaction using LightCycler. RESULTS: The hK11 mRNA levels were lower in tumor tissues from lung cancer (1.88 +/- 6.314) compared with adjacent nonmalignant lung tissues (8.271 +/- 9.002; n = 45; P = 0.0001). No significant difference was found among sex, age, clinical stages, tumor status, and lymph node metastasis. The hK11 mRNA levels were lower in moderately or poorly differentiated adenocarcinoma lung cancer (0.452 +/- 1.614) compared with well-differentiated adenocarcinoma lung cancer (1.728 +/- 2.829; P = 0.0281). The group with low hK11/gylceraldehyde 3-phosphate dehydrogenase levels (< 0.6) had a significantly worse prognosis compared with the group with high hK11/gylceraldehyde 3-phosphate dehydrogenase levels (> 0.6; log-rank test, P = 0.0131; Breslow-Gehan-Wilcoxon test, P = 0.0172). CONCLUSION: Cox proportional hazard regression model (multivariate analysis) indicated that pathologic stages (P = 0.0443) and low hK11 expression levels (P = 0.0469) were the prognostic factors of lung cancers. However, additional studies and a longer follow-up are needed to confirm the impact of hK11 on the biologic behavior of the tumor.

Adenocarcinoma↗

PubMed2006

Evaluation of the epidermal growth factor receptor gene mutation and copy number in non-small cell lung cancer with gefitinib therapy.

Several studies have suggested that epidermal growth factor receptor (EGFR) gene mutation, EGFR gene amplification, and some other biomarkers may be predictors of gefitinib sensitivity. We analyzed EGFR mutation and EGFR copy number in 22 gefitinib-treated non-small cell lung cancer (NSCLC) cases and their relation to the survival of patients. We also studied 143 gefitinib-naïve Japanese NSCLC cases. The erbB2 copy number was also studied in 59 gefitinib-naïve NSCLC cases. In gefitinib-treated patients, the presence of EGFR mutation was associated with a higher response rate to gefitinib and a longer overall survival, but the increased EGFR gene copy number was not. In gefitinib-naïve cases, EGFR mutation but not EGFR gene copy number was significantly correlated with gender, pathological subtypes, and smoking status. The erbB2 copy number was not significantly correlated with the EGFR mutation or EGFR copy number in 59 cases. In conclusion, EGFR mutation was a better predictor of clinical outcome in gefitinib-treated patients than the EGFR gene copy number.

Adenocarcinoma↗

PubMed2005

Uncommon V599E BRAF mutations in Japanese patients with lung cancer.

BACKGROUND: Recently, somatic mutations of the epidermal growth factor receptor (EGFR) gene and Braf gene were found in patients with lung cancer. These mutations might be correlated with a clinical response to molecular target therapy. Although a few Caucasian lung cancer patients harbored BRAF mutations, there have been no reports about the BRAF mutation in Japanese patients with lung cancer. MATERIALS AND METHODS: We investigated BRAF mutations in Japanese lung cancer patients. The study included 129 surgically removed lung cancer cases from Nagoya City University Hospital. Braf, EGFR, and erbB2 mutations also were analyzed by reverse transcript polymerase chain reaction (RT-PCR) and direct sequencing. RESULTS: In exon 15, one BRAF mutation (1796 thymine to adenine; V599E) was found in nonsmoking woman with well-differentiated adenocarcinoma. We detected the 43 EGFR mutations, including 19 at exon 19 and 20 at exon 21 from the 129 patients analyzed (33.3%). We also detected one erbB2 mutation from 76 patients analyzed. All these mutations existed exclusively. CONCLUSIONS: V599E BRAF mutation was uncommon in Japanese lung cancer. All three genes mutations were predominantly found in female nonsmoking subjects with adenocarcinomas. However, completely exclusive mutation status would help us to choose custom-made molecular target therapy for the lung cancer.

Adenocarcinoma↗

PubMed2005

Epidermal growth factor receptor gene mutation in non-small cell lung cancer using highly sensitive and fast TaqMan PCR assay.

Epidermal growth factor receptor (EGFR) gene mutations have been found in a subset of non-small cell lung cancer (NSCLC) with good clinical response to gefitinib therapy. A quick and sensitive method with large throughput is required to utilize the information to determine whether the molecular targeted therapy should be applied for the particular NSCLC patients. Using probes for the 13 different mutations including 11 that have already been reported, we have genotyped the EGFR mutation status in 94 NSCLC patients using the TaqMan PCR assay. We have also genotyped the EGFR mutations status in additional 182 NSCLC patients, as well as 63 gastric, 95 esophagus and 70 colon carcinoma patients. In 94 NSCLC samples, the result of the TaqMan PCR assay perfectly matched with that of the sequencing excluding one patient. In one sample in which no EGFR mutation was detected by direct sequencing, the TaqMan PCR assay detected a mutation. This patient was a gefitinib responder. In a serial dilution study, the assay could detect a mutant sample diluted in 1/10 with a wild-type sample. Of 182 NSCLC samples, 46 mutations were detected. EGFR mutation was significantly correlated with gender, smoking status, pathological subtypes, and differentiation of lung cancers. There was no mutation detected by the TaqMan PCR assay in gastric, esophagus and colon carcinomas. TaqMan PCR assay is a rapid and sensitive method of detection of EGFR mutations with high throughput, and may be useful to determine whether gefitinib should be offered for the treatment of NSCLC patients. The TaqMan PCR assay can offer us a complementary and confirmative test.

Adolescent↗

PubMed2005

Cobalt-filled apoferritin for suspended single-walled carbon nanotube growth with narrow diameter distribution.

Cobalt-filled apoferritin (Co-ferritin) was, for the first time, used as a wet catalyst for the synthesis of single-walled carbon nanotubes (SWNTs) with narrow diameter distribution. Co-ferritins were spin-coated and converted to cobalt nanoparticles by calcination. Using chemical vapor deposition, suspended networks of SWNTs were formed on pillar-structured substrates. The suspended SWNTs show narrow tube diameter distribution with a relatively good graphite structure. By virtue of the low diffusion coefficient of cobalt, Co-ferritin might be more useful for narrow diameter SWNTs growth than ferritins, which encase iron particles.

Animals↗

PubMed2005

Endoscopic thoracic sympathectomy for palmar hyperhidrosis: efficacy of T2 and T3 ganglion resection.

BACKGROUND: Endoscopic thoracic sympathectomy has been considered an effective treatment for palmar hyperhidrosis. However, the extent of resection has not been determined in terms of efficacy and complications. We compared the efficacy and complications of 2-ganglion and single-ganglion resection in patients with palmar hyperhidrosis. METHODS: From 1995 to 2000, 75 patients underwent resection of thoracic ganglion T2 and T3. From 2000 to 2003, 67 patients underwent resection of only the T2 ganglion. Eighty of the 142 patients (56%) answered a detailed questionnaire, the results of which were analyzed. RESULTS: Gender, age, family history, and distribution of sweating were similar in both groups. Recurrence rates 1 and 2 years after endoscopic thoracic ganglionectomy were between 0% and 3% in T2 and T3 resection, and between 15% and 19% in T2 resection only. In the combined T2 and T3 resection group, 100% of patients noticed compensatory sweating; in T2 resection, 90% of patients noticed compensatory sweating. As for rates of satisfaction, T2 and T3 resection was superior to T2 resection. CONCLUSIONS: High recurrence rates of palmar hyperhidrosis after single-ganglion resection are reported in the present study. Two-ganglion resection is a superior surgical method to prevent recurrence of palmar hyperhidrosis.

Adolescent↗

PubMed2005

Metal--semiconductor transition in single-walled carbon nanotubes induced by low-energy electron irradiation.

We report the effect of low-energy (1 keV) electron beam irradiation on gated, three-terminal devices constructed from metallic single-walled carbon nanotubes. Pristine devices, which exhibited negligible gate voltage response at room temperature and metallic single-electron transistor characteristics at low temperatures, when exposed to an electron beam, exhibited ambipolar field effect transistor (room temperature) and single-electron transistor (low temperature) characteristics. This metal-semiconductor transition is attributed to inhomogeneous electric fields arising from charging during electron irradiation.

Crystallization↗