Biomedical subjects

H Noma

Publications and source records attributed to H Noma.

At least 37 records · Page 2Linked to original sources

PubMed2001

Analysis of a role for p16/CDKN2 expression and methylation patterns in human oral squamous cell carcinoma.

The p16/CDKN2 (cyclin dependent kinase number 2) gene is known to be one of the negative regulators of the cell cycle. Aberrant 5'CpG island methylation is one of the most important mechanisms of p16/CDKN2 gene promoter region alteration. We studied 8 oral squamous cell carcinoma cell lines and 25 primary tumor tissues for the p16/CDKN2 gene and its expression by PCR-SSCP, MSP, RT-PCR, and immunohistochemical methods to determine the mechanism and the potential biological significance of p16/CDKN2 gene inactivation. In primary tumors, no p16/CDKN2 gene mutations were found by PCR-SSCP. However, hypermethylation of the CpG sites of p16/CDKN2 gene was observed in 48% (12/25) cases of primary tumors and in 50% (4/8) of cell lines. To verify the p16 mRNA expression, we employed RT-PCR and observed decreased or lacked p16 mRNA in 44% (11/25) of primary tumor tissues. In addition, hypermethylation was observed in 6 of the above 11 cases (55%). An immunohistochemistry assay was also performed with the primary tumor tissues, and a semi-quantitative method was used to evaluate the staining intensity of p16 protein. We observed 52% (13/25) negative nuclear staining. When we compared these results with clinicopathological stages, there was no statistical significance. These findings suggest that hypermethylation of p16/CDKN2 promoter region may be associated with p16/CDKN2 gene alteration.

Aged↗

PubMed2001

Allelic imbalance on the long arm of chromosome 21 in human oral squamous cell carcinoma: relationship between allelic imbalances (LOH and MSI) and clinicopathologic features.

Frequent allelic imbalances, including loss of heterozygosity (LOH) and microsatellite instability (MSI), have been found on the long arm of chromosome 21 (21q) in several types of human cancer. This study was designed to identify the tumor suppressor locus (or loci) associated with oral squamous cell carcinoma (SCC) on 21q. In order to understand the details of genetic alterations on chromosome 21, we performed polymerase chain reaction analysis of microsatellite polymorphisms corresponding to ten loci on this chromosome. We examined forty primary tumor tissues, forty corresponding normal tissues, and seven lymph node metastatic tissues. We identified novel tumor suppressor loci in this region in primary oral SCCs. To further determine the role of 21q deletions in oral cavity carcinogenesis, forty oral SCCs were examined for allelic imbalances (LOH or MSI) at 21q using ten microsatellite markers. Among these forty patients, twenty-six (65%) showed LOH at one or more loci. Deletion mapping of these tumors revealed four discrete, commonly deleted regions on the chromosome arm. Furthermore, we detected MSI in seventeen of those tested cases (42.5%). We compared our results with the clinicopathologic features. A number of sites displaying LOH at 21q could be detected in early stage lesions, and the frequencies of LOH tended to be higher in later clinical stages, but no statistical correlation was observed. Our results strongly suggest that allelic imbalances on 21q are involved in the development of oral SCC and that at least four different putative tumor suppressor genes contributing to the pathogenesis of this disease are present on 21q. Furthermore, allelic loss on 21q appears to be a useful indicator for evaluating the malignancy and prognosis of oral SCC, because the LOH of recurrent cases was more frequent than that of non-recurrent ones.

Adult↗

PubMed2001

A case of an ameloblastic fibro-odontoma arising from a calcifying odontogenic cyst.

This case report describes an ameloblastic fibro-odontoma arising from a calcifying odontogenic cyst (COC) in the mandible of a twenty-three-year old male. The patient was referred to the Department of Oral Surgery, Tokyo Dental College, on March 30th, 2000, complaining of a painful swelling, which had appeared three weeks earlier on his left mandibular molar region. In a pathological view, the lesion was a round cyst the size of a chicken-egg, dark red in color, and surrounded by a thick membrane. The cyst had an epithelium of varying thickness which included many ghost cells and an enamel-like structure on the inside, and a thick wall of connective tissue with an ameloblastic fibro-odontoma on the outside. Enamel organ-like epithelial islands were structured radially in the form of strands with immature dentin. Cytokeratin 19 was strongly immunoreactive in the epithelium of the lesion; osteopontin and osteocalcin reacted in the mesenchymal cells and weakly in the epithelial element of this tumor.

Adult↗

PubMed2001

Clinicostatistical study of ameloblastoma treatment.

The purpose of this study was to investigate the treatment of 190 cases of ameloblastoma in our department from 1966 to 1994. The statistical results with regard to age, sex and region agreed with those of other investigators. Thirty-five of 43 (81.4%) cases underwent enucleation in 1960s, but the sixteen of 27 (59.3%) cases underwent partial resection of mandible in 1990s. The defect of mandible was reconstructed with iliac bone grafting since 1968, grafts with a mixture of iliac blocked bone and PCBM (particulate cancellous bone and marrow) have been used since 1975. Grafting of the inferior alveolar nerve with the great auricular nerve to the defect has been performed in our department since 1977. Recently, technique involving pull-through of the inferior alveolar nerve bundle has been used in our department. When the reconstruction method for the mandible and nerve has been established, it becomes possible to operate radically and positively. Recurrence occurred in 17 cases after the primary enucleation. It is thought that the primary treatment of ameloblastoma must be as radical as possible. It appears to be necessary to observe progress and perform follow-up in cases of ameloblastoma for more than ten years, because there was one recurrence at 9 years and 4 months after the first operation. In fact, three quarters of our cases were lost to follow-up. Such losses can problems in confirming recurrence and responding rapidly.

Adolescent↗

PubMed2001

Hand-assisted laparoscopic distal pancreatectomy with minilaparotomy for distal pancreatic cystadenoma.

Two patients with cystic tumors of the pancreas treated by laparoscopic distal pancreatectomy are presented. The first patient was a 34-year-old woman with a 6-cm cystadenoma of the tail of the pancreas treated with a complete laparoscopic distal pancreatectomy. After mobilization of the distal pancreas and spleen, the pancreas was transected proximally together with the splenic artery and vein using an endoscopic linear stapler. The second patient was a 71-year-old woman with a 6-cm cystadenoma of the body of the pancreas, treated by hand-assisted laparoscopic distal pancreatectomy with minilaparotomy because the tumor was adjacent to the portal vein and celiac axis. Using an upper median minilaparotomy, dissection of the gastrocolic ligament, division of the splenic artery, and transection and closure of the pancreas were performed. Division of the splenic vein and mobilization of the distal pancreas and spleen were performed via a hand-assisted laparoscopic approach. There were no postoperative complications (such as pancreatic fistulas) in either patient, and the postoperative courses were uneventful. The patients returned to normal activity within 1 week after the operation. Complete laparoscopic and hand-assisted laparoscopic distal pancreatectomy are preferable to conventional open surgery for benign tumors of the pancreas because of their less-invasive nature. Additionally, in tumors of the body of the pancreas, hand-assisted laparoscopic distal pancreatectomy might have the advantages of laparotomy and laparoscopy in terms of handling the splenic artery and vein just below the minilaparotomy site, suggesting an easier and safer procedure than complete laparoscopic distal pancreatectomy. Therefore, hand-assisted laparoscopic distal pancreatectomy can be recommended as a useful alternative to complete laparoscopic distal pancreatectomy for selected patients with benign tumors of the body and tail of the pancreas.

Adult↗

PubMed2001

[Evaluation of postoperative pain relief by infiltration of bupivacaine or epidural block after laparoscopic cholecystectomy].

We compared the analgesic effect of bupivacaine infiltration into surgical wounds with that of epidural block after laparoscopic cholecystectomy (LC). Forty-five patients (ASA physical status I-II) for LC were randomized into three groups (n = 15 in each group). Patients received only general anesthesia (Group C), received infiltration of 0.5% bupivacaine into the surgical wound before surgery combined with general anesthesia (Group L), or received epidural anesthesia combined with general anesthesia (Group E). Postoperative pain was assessed using visual analogue scale (scale: 0-10) at 1, 2, 6 and 12 hours after the operation, the need for additional supplemental analgesics, and the cost of anesthesia. Visual analogue scale in Group C at 1, 2, or 6 hours was significantly greater than that of Group L and E. The number of patients who needed supplemental analgesics was 9 in Group C, 5 in Group L, and 2 in Group E. The cost of pharmaceutical and anesthetic practice of Group E was more expensive than Group L and C. In conclusion, infiltration of bupivacaine combined with general anesthesia is an effective and economical method of postoperative pain relief.

Anesthesia, Epidural↗

PubMed2001

Role of thymidine phosphorylase in Fas-induced apoptosis.

Thymidine phosphorylase (TP) has chemotactic and angiogenic activity in vitro, and it promotes tumor growth and inhibits apoptosis in vivo. It plays a key role in the invasiveness and metastasis of TP-expressing solid tumors. KB/TP cells transfected with a TP cDNA have been shown to be resistant to hypoxia-induced apoptosis, suggesting that TP has effects on tumor growth and cell death independent of its effects on angiogenesis. However, the mechanisms of cell death inhibition by TP are unknown. In the present study, we demonstrate that caspase-8 is cleaved in control transfectant KB cells early on during Fas-induced apoptosis. Caspase-8 activation leads to the loss of mitochondrial membrane potential, followed by the release of cytochrome c, the activation of caspase-3, and apoptosis. In contrast, Fas-induced caspase-8 cleavage is inhibited in KB/TP cells, which lead to inhibition of the downstream apoptotic cascade and inhibition of apoptosis. These findings indicate that TP plays an important role in intracellular apoptotic signal transduction in the Fas-induced apoptotic pathway. Therefore, inhibition of TP may suppress the progression of TP-overexpressing solid tumors by inducing apoptosis.

Apoptosis↗

PubMed2000

Morphologic changes in forearm flaps of the oral cavity.

PURPOSE: This study was undertaken to investigate the morphologic changes in the forearm flap in the oral environment. PATIENTS AND METHODS: Histologic evaluation of biopsy specimens from 20 forearm flaps was done 1 to 75 months after intraoral reconstruction after treatment of cancer. Hematoxylin and eosin and Azan were used to stain the deparaffinized sections. RESULTS: The clinical features of the grafted flap seemed to depend on the time since the operation. The cornified layer of the epidermis of the flaps showed thinning histologically. CONCLUSION: After 11 months of exposure to an intraoral environment, "mucosalization" of the forearm flap is evident.

Adult↗

PubMed2000

Aldehyde dehydrogenase 2 and glutathione S-transferase M 1 polymorphisms in relation to the risk for oral cancer in Japanese drinkers.

We investigated 191 patients with oral cancer (121 males and 70 females) and 121 non oral cancer patients (69 males and 52 females), both groups with a history of alcohol use. Blood was analyzed with aldehyde dehydrogenase 2 (ALDH 2) and glutathione S-transferase M 1 (GSTM 1) genotyping. ALDH 2 genotyping was performed by polymerase chain reaction (PCR)-Restriction fragment length polymorphism (RFLP) method and GSTM 1 genotyping was amplified with PCR using GSTM 1 specific primers. In the oral cancer group, the alcohol-drinking rate (59.7%) was significantly higher than in the non cancer group (alcohol-drinking rate 27.3%, p < 0.01). The incidence of inactive ALDH 2 and GSTM 1 in the cancer group with an alcohol-drinking habit was 34.2 and 67.5% and was higher than in the non cancer group with an alcohol-drinking habit (15.1, 45.5%).

Adult↗

PubMed2000

Repair of the inferior alveolar nerve with a forearm cutaneous nerve graft after ablative surgery of the mandible.

PURPOSE: A method of autologous nerve grafting for repair of the inferior alveolar nerve after mandibular resection using a forearm cutaneous nerve is described. PATIENTS AND METHODS: The lateral cutaneous nerve of forearm served as the donor nerve, and the graft was inserted microsurgically using an epineurial nerve suture technique in 6 subjects. Return of sensation in these 6 patients was measured by the use of Semmes-Weinstein method. RESULTS: Sensibility of the lower lip and chin recovered after about 10 months in all 6 subjects. CONCLUSION: The lateral branch of the forearm cutaneous nerve is a useful graft for repair of the inferior alveolar nerve after mandibular resection in which a forearm flap is used as part of the reconstruction.

Carcinoma, Squamous Cell↗

PubMed2000

Helicobacter pylori may have only a transient presence in the oral cavity and on the surface of oral cancer.

We used the reverse transcription polymerase chain reaction (RT-PCR) and culture methods to study the presence of Helicobacter pylori in the gastric and oral samples from a total of 116 gastritis and peptic ulcer patients, including 58 with oral cancer. Detection rates of H. pylori were 46.6% in stomach samples and 12.1% in oral swab samples. All of the oral cancer surface swab samples were positive for H. pylori, as were their gastric samples suggesting that oral H. pylori derived from the stomach. The culture supernatants of Streptococcus mutans and Prevotella intermedia inhibited the growth of the H. pylori strain and caused the formation of the coccal form. In cases where H. pylori was detected in the oral cavity samples, including the oral cancer surface samples, it was believed that this species had colonized the stomach and were present in the oral cavity only as a transient organism.

Bacterial Proteins↗

PubMed2000

Surgical simulation of Class III edentulous patient using a 3D craniofacial model: report of a case.

A case of edentulous prognathism in a 46-year-old Japanese male is presented. We described the outcome of the patient who underwent simultaneous sagittal splitting ramus osteotomy of the edentulous mandible, interpositional bone graft of severely atrophic edentulous jaws, and delayed placement of titanium implants for reconstruction. We highly recommend performing a surgical simulation using a craniofacial model of the patient's anatomy created using CT image data. The procedure provides almost ideal maxillary and mandibular contours.

Alveolar Ridge Augmentation↗

PubMed2000

N-acetyl cysteine inhibits cell cycle progression in pancreatic carcinoma cells.

The antioxidant N-acetyl cysteine (NAC) is a precursor of intracellular glutathione (GSH) and is also a well known as one of the chemopreventive agents which act through a variety of cellular mechanisms. We examined the effects of NAC on cell cycle progression in the pancreatic carcinoma cell lines, SW1990 and JHP1. Cells were incubated with or without NAC. Cell cycle distribution was analyzed by flow cytometry and immunoblotting. NAC suppressed cell proliferation in a concentration-dependent manner, whereas NAC increased intracellular glutathione content significantly in a dose-dependent manner. The percentage of cells in the G1 phase after treatment with NAC was significantly higher than the percentage seen for control cells. Cyclin D1 expression of carcinoma cells treated with NAC decreased remarkably compared with cells without NAC treatment. Thus, the antiproliferative effect of NAC by prolongation of the G1 phase in human pancreatic carcinoma cells shows its possible utility as an antitumor agent.

Acetylcysteine↗

PubMed1999

Use of bone turnover marker, pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), in the assessment and monitoring of bone metastasis in prostate cancer.

BACKGROUND: We investigated whether a new marker of bone turnover, pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), could be useful in the assessment of bone metastasis and in monitoring of the response to treatment in patients with prostate cancer with bone metastasis. METHODS: In all, 58 patients with prostate cancer (25 with bone metastasis and 33 without bone metastasis) and 52 patients with benign prostate hypertrophy who were treated between June 1994-August 1997 were included in this study. All patients were newly diagnosed. RESULTS: Serum ICTP levels in patients with prostate cancer with bone metastasis were significantly higher than those in patients with prostate cancer without bone metastasis (P<0.0001) or with benign prostate hypertrophy (P<0.0001). No significant differences were observed in serum ICTP levels between patients with prostate cancer without bone metastasis and those with benign prostate hypertrophy. Serum ICTP levels correlated significantly with Soloway's grading system for bone scans. Serum ICTP levels in patients with bone metastasis showed a significant downward trend in response to hormonal treatment. CONCLUSIONS: The determination of serum ICTP levels is useful in the assessment of bone metastasis and in monitoring the response of bone metastasis to treatment to prostate cancer.

Aged↗

PubMed1999

Repair of the mandibular nerve by autogenous grafting after ablative surgery of the mandible.

In this paper, we introduce our original method of autologous nerve grafting for substitution of the mandibular nerve after mandibular resection in three subjects. The lateral cutaneous nerve of the forearm served as a donor nerve, and the graft was imbedded microsurgically at the junctures using an epineurial nerve suture technique. Oversized grafts were chosen in order to insert them without tension in a space between the stumps of the recipient nerve and the regeneration zone of the bone. In all three subjects, sensibility of the lower lip and chin recovered completely after about ten months.

Case-Control Studies↗

PubMed1999

Clinical study of the pumping pressure changes in the temporomandibular joint space before and after arthroscopic surgery.

When arthroscopy of the temporomandibular joint (TMJ) is performed, we often observe differences in the resistance of hydraulic pressure during intra-articular pumping. It can be speculated that intra-articular adhesion and contracture of the capsule and ligament may cause these differences in resistance. In order to measure the changes in intra-articular hydraulic pressure before and after arthroscopic ablation surgery, seven cases were examined by balloon pumping technique. We concluded that the values of intra-articular hydraulic pressure are implicated in the severity of the internal derangement of TMJ.

Angioplasty, Balloon↗

PubMed1999

Blood flow monitoring by pulse oximetry during a forearm flap elevation.

The Allen's test for blood flow is performed before a forearm flap is elevated to examine vascularization through the ulnar artery. In this study, to ensure the survival of the donor site when a forearm flap was elevated, we monitored patients using a pulse oximeter. From oral cancer patients who were undergoing reconstructive surgery using the forearm flap, twenty patients were randomly selected to be served as subjects. A pulse oximeter probe was attached to the thumb on the side from which a skin flap was to be elevated. Oxygen saturation was measured when the tourniquet was released, and the radial artery was clamped and severed. The results showed that oxygen saturation temporarily decreased when the radial artery was ligated, but it recovered in one to two minutes.

Forearm↗

PubMed1999

Microvascular anastomosis in oral reconstructive surgery: a comparative study of recipient vessels between Japanese and German patients.

Specimens of recipient vessels were obtained from the oral and maxillofacial regions when carrying out microsurgery and the condition of the vascular wall was analyzed histopathologically. This study was performed in both Japan and Germany and the results were compared. A higher percentage and a more advanced abnormality of the recipient vessel seemed to exist in the German patients as compared to the Japanese patients. This difference could be due to the preoperative multimodal chemo- and radiotherapy more often applied in Germany and the higher incidences of systemic diseases such as hypertension and diabetes in the German population. The success rate of the surgery is, however, the same in both countries. It could be concluded that the viability of the flaps was not affected by preoperative damage to the recipient vessel.

Adult↗