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The aim of this study was to evaluate the influence of metal markers on dose distributions and dose evaluation indices in intensity modulated radiation therapy (IMRT) plans for prostate cancer. The dose distribution calculation in the prostate IMRT was performed in a virtual phantom with and without insertion of the metal markers. The deviations of Dmax, Dmin, homogeneity index (HI), Dmean, D2, D98, and D95 of clinical target volume (CTV) and planning target volume (PTV) were obtained for estimation of the influence on the dose evaluation indices. Analytical anisotropic algorithm (AAA) and Acuros external beam (AXB) algorithms were employed for calculating the dose distributions. There were no deviations in any dose evaluation indices in dose distributions calculated by using AAA, whereas the maximum deviations for CTV and PTV by using AXB were +7.93% and +6.43% for Dmax, -16.61% and -1.77% for Dmin, +29.46% and +8.34% for HI, +0.15% and +0.02% for Dmean, +1.50% and +0.24% for D2, respectively. Additional data were -0.20% in D98 (CTV) and -0.27% in D95 (PTV). This study suggests that local dose changes, which were produced around metal markers, affected dose distributions and the dose evaluation indices.

In postoperative radiotherapy for seminoma, control of the testicular absorbed dose is important, since exposure of the testis can lead to temporary or permanent infertility. In this case, instead of using a dog-leg-shaped field, treatment using a field focused near the aorta was provided in several disease stages of seminoma. However, the precise need for testicular shielding during treatment and dose of testis exposure was not clear. We examined these questions by measuring the testicular absorbed dose with and without a testicular shield using two clinical treatment plans and a phantom. The distance from the testis phantom and the lower end of the irradiation field was varied. Where the total dose for the tumor was 20 Gy, the testicular absorbed dose was below 0.1 Gy, the threshold dose for temporary infertility. At this dosage, the distance between the testis phantom and the edge of the irradiation field was 14.6 cm without the shield and 9.99 cm with the shield. Using a testes shield, it was thus possible to reduce the dose by 58.5%.

CyberKnife(®) provides continuous guidance through radiography, allowing instantaneous X-ray images to be obtained; it is also equipped with 6D adjustment for patient setup. Its disadvantage is that registration is carried out just before irradiation, making it impossible to perform stereo-radiography during irradiation. In addition, patient movement cannot be detected during irradiation. In this study, we describe a new registration system that we term "Machine Vision," which subjects the patient to no additional radiation exposure for registration purposes, can be set up promptly, and allows real-time registration during irradiation. Our technique offers distinct advantages over CyberKnife by enabling a safer and more precise mode of treatment. "Machine Vision," which we have designed and fabricated, is an automatic registration system that employs three charge coupled device cameras oriented in different directions that allow us to obtain a characteristic depiction of the shape of both sides of the fetal fissure and external ears in a human head phantom. We examined the degree of precision of this registration system and concluded it to be suitable as an alternative method of registration without radiation exposure when displacement is less than 1.0 mm in radiotherapy. It has potential for application to CyberKnife in clinical treatment.

The purpose of this study was to verify the dose absorbed by an implantable cardioverter defibrillator (ICD) from an (192)Ir sealed source during uterine intracavitary brachytherapy, and to confirm its immunity to radiation effects. First, prior to treatment, the doses around the ICD position of an anthromorphic phantom were evaluated. Next, we also measured the dose at the ICD position using a fluorescent glass dosimeter and silicon diode dosimeter during the treatment of intracavitary brachytherapy of a patient implanted with an ICD. The results of the phantom study showed the dose percentage at the ICD location, 2 cm deep, to be 0.074% of the prescribed dose. The results of a treatment study similarly showed the dose, measured using a fluorescent glass dosimeter in the ICD position, to be 0.071% of the prescribed dose. During the application of the total prescribed dose, 30 Gy/5 fraction, the dose at the surface of the ICD position was estimated to be 21.2 mGy, well below the 1 Gy maximum recommended in the JASTRO guidelines. We regard dose verification and monitoring during treatment to be both necessary and useful in the treatment of individual cases.

AML1/RUNX1 is an essential transcription factor involved in the differentiation of hematopoietic cells. AML1 binds to the Runt-binding double-stranded DNA element (RDE) of target genes through its N-terminal Runt domain. In a previous study, we obtained RNA aptamers against the AML1 Runt domain by systematic evolution of ligands by exponential enrichment and revealed that RNA aptamers exhibit higher affinity for the Runt domain than that for RDE and possess the 5'-GCGMGNN-3' and 5'-N'N'CCAC-3' conserved motif (M: A or C; N and N' form Watson-Crick base pairs) that is important for Runt domain binding. In this study, to understand the structural basis of recognition of the Runt domain by the aptamer motif, the solution structure of a 22-mer RNA was determined using nuclear magnetic resonance. The motif contains the AH(+)-C mismatch and base triple and adopts an unusual backbone structure. Structural analysis of the aptamer motif indicated that the aptamer binds to the Runt domain by mimicking the RDE sequence and structure. Our data should enhance the understanding of the structural basis of DNA mimicry by RNA molecules.

AML1 (RUNX1) is a key transcription factor for hematopoiesis that binds to the Runt-binding double-stranded DNA element (RDE) of target genes through its N-terminal Runt domain. Aberrations in the AML1 gene are frequently found in human leukemia. To better understand AML1 and its potential utility for diagnosis and therapy, we obtained RNA aptamers that bind specifically to the AML1 Runt domain. Enzymatic probing and NMR analyses revealed that Apt1-S, which is a truncated variant of one of the aptamers, has a CACG tetraloop and two stem regions separated by an internal loop. All the isolated aptamers were found to contain the conserved sequence motif 5'-NNCCAC-3' and 5'-GCGMGN'N'-3' (M:A or C; N and N' form Watson-Crick base pairs). The motif contains one AC mismatch and one base bulged out. Mutational analysis of Apt1-S showed that three guanines of the motif are important for Runt binding as are the three guanines of RDE, which are directly recognized by three arginine residues of the Runt domain. Mutational analyses of the Runt domain revealed that the amino acid residues used for Apt1-S binding were similar to those used for RDE binding. Furthermore, the aptamer competed with RDE for binding to the Runt domain in vitro. These results demonstrated that the Runt domain of the AML1 protein binds to the motif of the aptamer that mimics DNA. Our findings should provide new insights into RNA function and utility in both basic and applied sciences.

During upper endoscopic screening, a 71-year-old asymptomatic woman was found to have a small, yellowish, superficial elevated lesion in the upper third of her stomach, without any signs of atrophic mucosa. The patient underwent endoscopic follow-up once a year for approximately five years; however, changes in the tumor were barely detectable. Endoscopic mucosal resection was performed, and a histological examination confirmed the diagnosis of gastric adenocarcinoma with chief cell differentiation (GA-CCD). GA-CCD is rare; therefore, its clinicopathological features remain unknown. This case suggests that only barely detectable endoscopic changes may be observed in GA-CCD during long-term follow-up.

The monitor unit (MU) was calculated by pencil beam convolution (inhomogeneity correction algorithm: batho power law) [PBC (BPL)] which is the dose calculation algorithm based on measurement in the past in the stereotactic lung irradiation study. The recalculation was done by analytical anisotropic algorithm (AAA), which is the dose calculation algorithm based on theory data. The MU calculated by PBC (BPL) and AAA was compared for each field. In the result of the comparison of 1031 fields in 136 cases, the MU calculated by PBC (BPL) was about 2% smaller than that calculated by AAA. This depends on whether one does the calculation concerning the extension of the second electrons. In particular, the difference in the MU is influenced by the X-ray energy. With the same X-ray energy, when the irradiation field size is small, the lung pass length is long, the lung pass length percentage is large, and the CT value of the lung is low, and the difference of MU is increased.

We previously studied dose distributions of stereotactic radiotherapy (SRT) for lung cancer. Our aim is to compare in combination pencil beam convolution with the inhomogeneity correction algorithm of Batho power low [PBC (BPL)] to the anisotropic analytical algorithm (AAA) by using the dose evaluation indexes. There were significant differences in D95, PTV mean dose, homogeneity index, and conformity index, V10, and V5. The dose distributions inside the PTV calculated by PBC (BPL) were more uniform than those of AAA. There were no significant differences in V20 and mean dose of total lung. There was no large difference for the whole lung. However, the surrounding high-dose region of PTV became smaller in AAA. The difference in dose evaluation indexes extended between PBC (BPL) and AAA that as many as low CT value of lung. When the dose calculation algorithm is changed, it is necessary to consider difference dose distributions compared with those of established practice.

Bone morphogenetic protein (BMP)-2 plays an important role in bone growth and regeneration; however, BMP-2 is easily lost by diffusion through body fluid and has some inhibitory pathways. To address this problem, we previously immobilized recombinant human BMP-2 (rhBMP-2) on succinylated type I atelocollagen. Here, we examined the effect of immobilized rhBMP-2 in vitro and vivo. In ST2, MC3T3-E1, and C2C12 cells, alkaline phosphatase activity, which is a marker of osteoblast differentiation, was enhanced more by immobilized than nonimmobilized rhBMP-2. In addition, the phosphorylation of receptor-activated Smads, part of the signaling pathway activated by BMP-2, was prolonged by immobilized rhBMP-2 in these cells. Furthermore, implantation of immobilized rhBMP-2 into the backs of rats promoted the formation of mature bone-like structure. These results demonstrate that immobilized rhBMP-2 has higher bioactivity than nonimmobilized rhBMP-2, and, therefore, immobilization of rhBMP-2 can prolong BMP signaling., ((c) 2008 Wiley Periodicals, Inc.)

The mechanism underlying airway hyperresponsiveness (AHR), a characteristic feature of asthma, remains obscure. We attempted to elucidate the mechanism responsible for the different degrees of AHR in two mouse strains, BALB/c and C57BL/6, following exposure to an anaphylactic trigger. When ovalbumin (OVA)-sensitized mice were challenged daily with OVA for up to three consecutive days, the BALB/c mice showed a higher degree of airway responsiveness to methacholine than did C57BL/6. Following the OVA challenge, eosinophils and macrophages in bronchoalveolar lavage fluid (BALF) from BALB/c increased significantly in number compared to those from C57BL/6. BALB/c mice also exhibited a higher serum IgE level than that of C57BL/6 after OVA challenge. The enhanced AHR and eosinophilic infiltration in BALF were significantly reduced by pretreatment with a selective cysteinyl-leukotriene type 1 receptor (cysLT(1)R) antagonist, montelukast. In the in vitro study, cysLT production was significantly lower in the dissected lung tissue from BALB/c than in tissue from C57BL/6 when both groups were stimulated with saline. The lungs from BALB/c generated significantly larger amounts of cysLTs on incubation with OVA rather than with saline, while the lungs from C57BL/6 did not show any significant increase in cysLTs with antigen stimulation. Significant upregulation of cysLT(1)R and cysLT(2)R mRNA expression was induced by OVA challenge in the lungs of BALB/c, but not in those of C57BL/6. It is suggested that, after an anaphylactic reaction, the degree of AHR is dependent on the genetic background and that cysLTs play an important role in the mechanism involved.

Through an exhaustive search for Escherichia coli aminoacyl-tRNA synthetase(s) responsible for the misacylation of yeast suppressor tRNA(Tyr), E. coli lysyl-tRNA synthetase was found to have a weak activity to aminoacylate yeast amber suppressor tRNA(Tyr) (CUA) with L-lysine. Since our protein-synthesizing system for site-specific incorporation of unnatural amino acids into proteins is based on the use of yeast suppressor tRNA(Tyr)/tyrosyl-tRNA synthetase (TyrRS) pair as the "carrier" of unusual amino acid in E. coli translation system, this misacylation must be repressed as low as possible. We have succeeded in effectively repressing the misacylation by changing several nucleotides in this tRNA by genetic engineering. This "optimized" tRNA together with our mutant TyrRS should serve as an efficient and faithful tool for site-specific incorporation of unnatural amino acids into proteins in a protein-synthesizing system in vitro or in vivo.

Because T7 RNA polymerase has a strong preference for particular sequences to initiate transcription, some RNAs having pyrimidine-rich sequences at their 5'-end (yeast tRNA(Tyr), for example) are hardly transcribed by this enzyme. To circumvent this inconvenience, we have developed an efficient method for in vitro preparation of such tRNAs. The RNA of interest is first transcribed as a precursor form that has purine-rich extra sequences at its 5'-end, then processed with RNase P to generate the objective tRNAs. By using this protocol, we were able to prepare easily and efficiently yeast tRNA(Tyr) transcript and its mutants harboring base substitutions within the anticodon loop and/or acceptor stem regions. Aminoacylation analyses of these tRNA transcripts with yeast tyrosyl-tRNA synthetase revealed that the replacement of G34 by C34 (mutation to amber suppressor) severely impaired the aminoacylation, whereas the replacement of the U4:G69 wobble base-pair in the acceptor stem region by C4:G69 normal Watson-Crick type base-pair improved it.

Repair of bone defects remains a major concern in plastic and maxillofacial surgery. Based on modern concepts of tissue engineering, periosteum has gained attention as a suitable osteogenic material. We tested the hypothesis that surgically released and immediately repositioned periosteum would exhibit high osteogenic capacity upon grafting in a rat calvarial defect. Seven days after periosteum was released from the tibia and immediately repositioned, the "primed periosteum graft" (PPG; n = 15) was placed into a critical-sized defect of rat calvaria and the process of bone formation was evaluated histologically, immunohistologically, and radiographically at 7, 14, and 21 days after grafting. Findings were compared with a nonprimed periosteal graft (NPG; n = 15). Endochondral ossification was observed in both the PPG and NPG. The PPG showed higher expression of proliferative cell nuclear antigen, bone morphogenetic protein, and vascular endothelial growth factor than the NPG. Three-dimensional radiographic examination revealed significantly increased bone formation in the PPG than in the NPG (P < 0.01). These findings suggested that surgical stimulation of the periosteum enhanced the osteogenic potential of periosteal cells. This method may be suitable for the clinical repair of bone defects.

Vessel invasion is an important step in cartilage replacement that leads to bone formation, and vascular endothelial growth factor (VEGF) has been implicated as a key player in this process. Although grafted periosteum undergoes endochondral ossification, little is known about the role of VEGF in this process. In the current study the authors investigated by immunohistochemical, histochemical, and ultrastructural techniques the localization of VEGF during bone formation in periosteal grafts. At day 14 after grafting the tibias of Japanese white rabbits, periosteal cells in the grafted tissue had differentiated into chondrocytes to form cartilage. Some chondrocytes were immunopositive for VEGF expression, and subsequent vessel invasion occurred predominantly in these VEGF-positive areas. At day 45, the cartilage invaded by blood vessels had been replaced by newly formed bone. These findings suggest that VEGF is associated with the process of blood vessel invasion into cartilage before bone replacement in endochondral ossification from grafted periosteum.

While several reports have documented immunosuppressant-induced osteoporosis, the exact mechanism of the pathological change of the joint remains to be clarified. In the present study, we have demonstrated the pathological change of the articular cartilage in the mandibular head of five Sprague-Dawley rats administered with the immunosuppressant FK 506 for 28 days. Three-dimensional micro-computed tomography of the mandibular heads in treated rats showed a significant decrease in trabecular bone volume compared to control rats. Histological observation revealed atrophic change of the articular cartilage. Immunohistological observation using anti-proliferative cell nuclear antibody (PCNA), type I, II, and type X collagen antibodies showed significantly decreased proliferation and differentiation of chondrocytes in the articular cartilage compared with the control group (p<0.05). Tartrate-resistant acid phosphatase (TRAP) staining revealed no significant difference in the numbers of osteoclasts at the chondro-osseous junction. Thus, FK 506 administration inhibited chondrogenic cell proliferation and differentiation and might cause osteoporotic change of subcartilage trabecular bone that subsequently forms in the mandibular head.

After organ transplantation, severe osteoporosis is occasionally seen, and the use of immunosuppressants is thought to be one of the causes of such osteoporosis. In the present study, we investigated the effects of FK506 monotherapy on bones and determined the mechanism of onset of osteoporosis, both by assessing chronological changes in bone metabolism and by identifying factors that facilitate bone resorption. In 8-week-old male Sprague-Dawley rats, FK506 (1 mg/kg) was injected intraperitoneally every day for 5 weeks (FK506-treated group), and for comparison, physiological saline was administered in the same manner in a control group of rats. Serum and urine samples were collected at weeks 0, 1, 3, and 5 of administration. The femur and tibia were collected within 24 h of the final administration. When compared to the control group, findings on three-dimensional micro-computed tomography of the femur for the FK506-treated group showed a significant decrease in trabecular bone volume. The level of serum osteocalcin in the FK506-treated group at week 1 of administration was significantly higher than the control. Throughout the administration period, the sum of urinary pyridinoline (PYD) and deoxypyridinoline (Dpd) was significantly higher in the FK506-treated group. Of the various bone resorption factors tested, the level of serum parathyroid hormone (PTH) in the FK506-treated group was significantly higher than the control at week 3 of administration. The results of the present study confirmed that FK506 monotherapy in rats induced high-turnover osteoporosis. Soon after the start of FK506 administration, bone formation and resorption were elevated, and PTH appeared to have been involved in the maintenance of the elevated bone resorption., (Copyright 2004 Springer-Verlag)

Purpose: To clarify the involvement of bone morphogenetic proteins (BMPs) in the proliferation and differentiation of osteo/chondrogenic cells during the process of bone formation from grafted periosteum., Material and Methods: Tibial periosteum of young Japanese white rabbits was grafted into suprahyoid muscles and removed after 7, 9, 14 or 21 days. BMP-2, -4, proliferative cell nucleus antigen (PCNA) immunoreaction and Alcian blue staining in grafted periosteum was then sought microscopically., Results: PCNA positive cells in the grafted periosteum expressed BMP-2 at 7 days. These cells differentiated into chondroblasts that expressed BMP-2 and Alcian blue at 9 days. After 14 days, cartilage formation was seen, and BMP-2 and -4 expressions were observed in mature and hypertrophic chondrocytes. Endochondral ossification was observed at 21 days and osteoblasts showed both BMP-2 and -4 expression., Conclusion: Both BMP-2 and -4 appear to play regulatory roles in the process of endochondral ossification from grafted periosteum, due to their involvement in the proliferation and differentiation into chondrogenic and osteogenic cells.

Introduction: The pathogenetic features of rheumatoid arthritis of the temporomandibular joint (TMJ) are not well defined. In this paper the histological features of TMJs affected by rheumatoid arthritis, and the detection of secondary amyloidosis and macrophage populations in the TMJs of two patients with progressive rheumatoid arthritis are described., Methods: In two patients (64-year-old man and 61-year-old woman) with rheumatoid arthritis total TMJ replacement were performed. The surgical specimens were studied histologically., Results: It was found that the articular cartilage had been completely replaced by proliferating fibrous tissue. Congo red staining and polarizing microscopy revealed amyloid deposition in the connective tissue of the joint space. Immunohistochemical staining showed CD 68 positive macrophages around the amyloid deposition in the proliferating soft tissue., Conclusion: TMJ involvement in rheumatoid arthritis followed the same destructive pathway as in other joints. Amyloid deposition and macrophage populations were detected in two TMJs affected by rheumatoid arthritis.

Grafted periosteum has a rich potential to induce heterotopic bone formation. In the current study the authors investigate whether autogenous periosteal grafts can regenerate the mandibular head in a rabbit model. They removed the mandibular head of Japanese white rabbits and grafted tibial periosteum to the cut surface of the mandible. Grafted periosteum was observed histologically and radiographically at day 7, 14, 21, and 45 after surgery. At day 7 after grafting, grafted tissue showed remarkable cell proliferation. By 14 days these cells had differentiated into chondrocytes to form cartilage, and endochondral ossification took place after 21 days. At 45 days after surgery, soft X-ray findings showed a newly formed mandibular head, which was similar histologically to that of a normal mandibular head. The cut mandible without periosteal graft showed no regeneration. These findings indicate that grafted periosteum can regenerate the mandibular head without special procedures such as bone fixation in a rabbit model, and suggest that this technique may be useful clinically.

Cisplatin (CDDP) is a useful drug for the treatment of malignant solid tumors of the head and neck. Because CDDP includes the heavy metal platinum as a component, it is thought metallothionein (MT) may be involved in CDDP-resistance. However, functional differences between the four MT isoforms (MT-I, II, III and IV) remain unclear. The aim of this study was to investigate the relationship between MT isoform expression and CDDP-resistance. Two human tongue squamous cell carcinoma cell lines not exposed to anticancer chemotherapy were studied. The cell lines were subjected to reverse transcriptase-polymerase chain reaction (RT-PCR) analysis before and after CDDP-treatment. Both cell lines expressed MT-I/II and MT-IV isoforms but not the MT-III isoform. Following CDDP treatment, MT-I/II mRNA levels were induced only in the CDDP-resistant cell line. Our results showed that expression of the MT I/II isoform was induced by CDDP treatment, and may play an important role in CDDP-resistance in squamous cell carcinoma of the human tongue.

To determine whether grafted young periosteum can induce new bone formation in elderly patients, this preliminary study evaluated cell proliferation and differentiation in xenogeneic periosteal grafts in old rats radiographically, histologically, and immunohistochemically. Periosteum harvested from the tibia of young Japanese white rabbits were grafted into old Sprague-Dawley rats with or without administration of 1.0 mg per kilogram per day immunosuppressant FK506. Autogenous old periosteal tissue grafts were also evaluated as a control. Grafted tissue was extirpated after 7, 14, 21, and 45 days. In the xenogeneic group, proliferative cell nuclear antigen-positive cells were observed 7 days after surgery, which differentiated into chondroblasts with bone morphogenetic protein-2 expression and finally formed cartilage by 14 days. Endochondral ossification was observed at 21 days, and bone replacement was completed by 45 days. No osteogenic cell activity was observed in the two other groups. Xenogeneic young periosteum thus maintained its osteogenic/chondrogenic potentiality in older rats.

Objectives and Design: It has been previously reported that alpha-defensin (HNPs) and beta-defensin-2 (HBD-2) peptides with antifungal and cytotoxic activities can be detected in oral carcinomas and the saliva of patients with oral carcinomas. The present study investigated the presence of HNPs and HBD-2 in oral epithelia with candidiasis., Materials and Methods: Tissue sections (4 microm) were prepared from biopsy and surgically removed specimens diagnosed as oral candidiasis (n = 10). The sections were examined immunohistochemically with antibodies directed against HNPs and HBD-2., Results: Tissue sections of oral candidiasis were immunostained with antidefensin antibodies. Neutrophils in the inflamed lamina propria were positively immunostained with anti-HNPs antibody. The cytoplasm of cells in the upper spinous layer, in the lower spinous layer and in the parakeratinized layer of buccal epithelia with candidiasis was immunostained intensely with anti-HBD-2 antibody. In contrast, the expression of HBD-2 in the normal spinous layer was much weaker than that in oral candidiasis. No signals of HNPs were found in normal buccal epithelium., Conclusion: Buccal specimens from individuals with oral candidiasis show greater levels of expression of both HNPs and HBD-2. There might be a dual protection manner by defensins against fungal inflammation in infected buccal epithelia locally. Generally, HBD-2 signals have been found everywhere in the buccal epithelium; however, in an infected area, the signal intensity of HBD-2 has increased. HNPs signals have not been found in the normal buccal epithelium; however, HNPs signals have increased when the infection occurred.

Purpose: The purpose of the study was to determine whether a prefabricated graft of new bone induced from periosteum grafted into muscle was an effective material for the repair of jaw defects., Material and Methods: Artificial mandibular jaw defects in young Japanese rabbits were covered either with free grafted periosteum (n = 5) or a prefabricated graft of newly formed bone induced from periosteum, which was first grafted into the floor of the mouth, and placed as a revascularized muscle-pedicled bone flap (n = 5). Bone formation in jaw defects was examined radiographically and histologically 28 days after grafting into defects., Results: Bone formation was confirmed radiographically and histologically in both groups. However, the free grafted periosteum formed thin bone and fibrous tissue existed between the new and the original bone. In contrast, more active bone formation was observed with the prefabricated graft. This grafted new bone developed further and fused to the mandible. Blood vessels surrounding the new bone were observed histologically., Conclusion: These experimental findings suggested that prefabricated bone grafts induced from periosteum grafts are potentially useful for correction of jaw defects.

The purpose of this study was to demonstrate the immunohistochemical localization and distribution of human alpha- and beta-defensins, peptides with antimicrobial activity, in oral mucoepidermoid carcinoma tissue. Tissue samples were embedded in paraffin and alpha- and beta-defensins were immunostained by the streptavidin-biotin coupled peroxidase method. Cancer cells that constituted the ducts, as well as neutrophils, were positively immunostained with the anti-alpha-defensin antibody (HNPs). On the other hand, epidermoid cells and intermediate cells were intensely stained with the anti-beta-defensin-2 (HBD-2) antibody. Mucous-secreting cells were clearly not immunostained with the anti-HBD-2 antibody. The epithelial hyperplasia region adjacent to the tumor tissues was also positively immunostained with the anti-HBD-2 antibody.

The purpose of this study was to demonstrate immunohistochemically the localization and distribution of human beta-defensin-2 (HBD-2), a peptide with antimicrobial activity, in oral carcinoma tissues. Tissue samples were embedded in paraffin, and HBD-2 was immunostained by the streptavidin-biotin coupled peroxidase method. Cancer cells in the cornified region of well differentiated squamous cell carcinomas were stained intensely. Stained cancer cells detected by anti-HBD-2 antibody were scattered among the cells of the non-cornified region.

The purpose of this study was the immunohistochemical localization and distribution of HNP-1 in the submandibular glands of patients with oral carcinomas. Tissue sections were embedded in paraffin, and HNP-1 was immunostained by the streptavidin-biotin coupled peroxidase method. Striated duct cells in the submandibular glands were stained with anti-defensin antibody. Neutrophils and capillary intimal cells were also stained. Defensins (HNPs) are peptides that occur in neutrophils and protect against bacteria and tumor cells. Human alpha-defensin-1 (HNP-1) is such a peptide, possessing both antimicrobial and cytotoxic activities. The presence of HNP-1 in striated duct cells in the submandibular glands of oral cancer patients, suggests a likely role in tumor immunity, for this peptide.

The saliva of patients with oral squamous cell carcinoma was subjected to reversed-phase HPLC, and a peak (P 14) was eluted with a linear gradient of acetonitrile. The molecular weight of P14 was 3,442 daltons by mass spectrometry. The results of amino acid sequencing by Edman degradation and homology studies indicated that P14 was consistent with a peptide, human alpha-defensin 1 (HNP-1) which belongs to the defensin family. The concentration of HNP-1 in the saliva of 6 squamous cell carcinoma patients before surgery and 11 after surgery was 12.3 +/- 8.6 and 6.5 +/- 5.9 micrograms/ml (mean +/- S.D.), respectively. In contrast, minimal amounts of HNP-1 were found in the saliva of adenocarcinoma patients and healthy volunteers. The concentration of salivary HNP-1 correlated positively with serum squamous cell carcinoma related antigen (SCC-Ag)level (r = 0.879, p < 0.01).

Preoperative pelvic computed tomographic (CT) images were analyzed in 50 patients with rectal carcinoma to evaluate the depth of mural invasion. Firstly the rectum was inflated with air. Secondly cross-sectional CT images of the rectal carcinoma were taken, in all cases referring to lateral scout view films and barium enema films. The circle rate of the tumor was determined in the cross-sectional image. Perirectal changes on CT were evaluated where there were spiculated and nodular appearances. The circle rate correlated with the extent of mural invasion. In cases within 1/3 circle in the circle rate and without perirectal nodular appearance, more than 90% of the tumors were limited to the muscularis propria of the rectal wall. These findings were very useful for assessing suitable surgical treatment.

Intra-arterial infusion chemotherapy using an implantable reservoir was used for 22 patients with liver metastasis from September 1986 to March 1990. The material consisted of 8 subjects with gastric cancer and 14 with colorectal cancer. One had metastasis in one lobe (H1), 10 had a few scattered metastases in both lobes (H2) and 11 had numerous metastases in both lobes (H3). In 5 cases, a reservoir was implanted to prevent the recurrence after hepatectomy. Infusion catheter was placed in the proper hepatic artery in 5 cases via the gastroduodenal artery at laparotomy and it was carried out subcutaneously via the femoral artery in 17 cases. In all cases intra-arterial infusion of 5-FU was continuously administered followed by intermittent one shot injection of ADM. The clinical effectiveness of the therapy was well evaluated. One-year cumulative survival rate of all cases by Kaplan-Meier method was 55% and that of H2 cases was 78%. No recurrence was noted in post hepatectomy cases. Eight cases (36.3%) showed remarkable complications, which made it impossible to continue intra-arterial infusion chemotherapy: hepatic artery occlusion (3 cases), infection (2 cases), abdominal pain (1 case), hematoma in the implanted site (1 case) and dislocation of the infusion catheter (1 case). From the present study, it is considered that intra-arterial infusion chemotherapy is a useful procedure for the control of liver metastasis. Regimens for improved chemotherapy and the maintenance of more useful and safer catheters should therefore be investigated for further development of the therapeutical estimation.

A quantitative structure-activity relationship has been formulated for 646 antimalarials acting against P. berghei in mice. The equation developed has 14 terms, 9 of which are indicator variables. The correlation coefficient for the QSAR is 0.898 and the standard deviation is 0.309. The antimalarials are all arylcarbinols of the type X-ArCHOHCH2NR1R2. Sixty different aryl structures, including a variety of heterocyles, are contained in the study. The most important determinate of activity is found to be the electron-withdrawing ability of the substituents X; the hydrophobic character of X and R plays less important roles. Suggestions for more potent analogues are made and the lack of activity of about 100 additional analogues is also considered.

The synthesis and antiallergic activity of a new series of 9H-xanthen-9-one-2-carboxylic acids are described. Antiallergic activity was evaluated in the rat passive cutaneous anaphylaxis (PCA) screen. Biological results were analyzed using regression analysis techniques, and the antiallergic activity of the compounds in the series was found to be highly correlated with substituent size.

A quantitative structure-activity relationship (QSAR) for the inhibition of dihydrofolate reductase from S. faecium by quinazolines has been formulated. This is compared with a QSAR for inhibition of E. coli dihydrofolate reductase by 2,4-diamino-5-benzylpyrimidines. The QSAR for inhibition of bacterial enzyme is compared with QSAR for mammalian enzyme inhibition. A QSAR has been formulated for the antimalarial action of quinazolines against P. berghei in mice. The antimalarial QSAR is consistent with that of the in vitro bacterial study.

Carcinoma arising from a chronic anal fistula is an uncommon condition. A 53-year-old woman visited our clinic, complaining of refractory anal fistulas that had persisted for over a period of 15 years, which had started to discharge pus and mucus through external fistulous openings several months ago. A cytologic study of the perianal discharges and a biopsy of the external openings were useful in preoperatively detecting a cancer complicating an anal fistula. An abdominoperineal rectal amputation with an extended dissection of the relevant lymph nodes was performed. Histopathological findings revealed a mucus-producing adenocarcinoma with ly1, v0 in vessel invasion, and the stage of cancer was determined as being stage II, H0P0a2n0 (0/129). It is emphasized that cancer should be suspected whenever examining an old fistula, especially one with mucous discharges.

A quantitative structure-activity relationship (QSAR) has been formulated for quinazolines causing 50% inhibition of liver dihydrofolate reductase. The QSAR for the quinazolines is compared with QSAR for triazine and pyrimidine inhibitors. The three QSAR suggest new possibilities for the design of inhibitors of mammalian dihydrofolate reductase.