Multilocular thymic cyst detected during COVID‑19 treatment in an HIV‑positive adult man: A case report and literature review

A multilocular thymic cyst (MTC) is a rare mediastinal tumor with multiloculated cyst-like structures in the anterior mediastinum. This tumfor is associated with inflammatory diseases, including human immunodeficiency virus (HIV) infection. The present study reports a case of MTC detected during coronavirus disease 2019 (COVID-19) treatment in an adult who was tested HIV positive. An anterior mediastinal tumor was incidentally detected on computed tomography in a 52-year-old man with a 20-year history of HIV infection on the 9th day of COVID-19. The patient was asymptomatic with no notable physical findings. Magnetic resonance imaging revealed a 28-mm bilocular cyst. Robot-assisted thoracoscopic tumor resection was performed. Pathological examination showed that the cyst was lined with squamous or cuboidal epithelium, and the cystic lesion wall was mainly composed of thymic tissue with follicular hyperplasia. Based on these findings, the patient was diagnosed with MTC. To date, only 15 MTC cases have been reported in patients with HIV, and the majority of cases showed HIV infection-related symptoms such as lymphoid interstitial pneumonia and parotid gland enlargement. The present case was atypical for an HIV-related MTC because it did not involve HIV infection-related symptoms, suggesting the possibility for an alternative etiology such as COVID-19. Further reports on MTC development in patients with COVID-19 are required to elucidate the relationship between MTC and COVID-19.

A case of idiopathic multicentric Castleman disease with pulmonary hyalinizing granuloma-like multiple pulmonary nodules

A 41-year-old man presented with chronic cough and chest pain. Laboratory tests revealed anemia, inflammation, hypoalbuminemia, polyclonal hypergammaglobulinemia, and elevated interleukin-6 levels. Computed tomography revealed diffuse bilateral pulmonary nodules and multicentric lymphadenopathy. Histopathology of the pulmonary nodule resembled pulmonary hyalinizing granuloma (PHG), whereas lymph node histopathology was consistent with idiopathic multicentric Castleman disease (iMCD). The patient was diagnosed with iMCD involving PHG-like pulmonary nodules. Little is known about the association between these two diseases, and the present case provides insights regarding the relationship between PHG and iMCD.

OP0110 CELL-TYPE-SPECIFIC TRANSCRIPTOME ARCHITECTURE UNDERLYING THE ESTABLISHMENT AND EXACERBATION OF SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unknown etiology involving multiple immune cells and has diverse clinical phenotypes. This heterogeneous nature has hampered a better understanding of SLE pathogenesis and the development of effective therapeutic agents. While recent single-cell RNA sequencing studies of SLE identified several important cell subpopulations, they were limited by sparse expression information at single-cell level and small sample sizes.

Objectives

This study aimed to elucidate the dysregulated gene expression pattern linked to multiple clinical statuses of SLE with a fine cellular resolution and higher sensitivity. We also attempted to resolve a complex interaction between risk variants and the transcriptome dysregulation seen in SLE patients.

Methods

We conducted a large-scale bulk transcriptome study of 6,386 RNA-sequencing data including 27 purified immune cell types in peripheral blood from 136 SLE and 89 healthy donors in the Immune Cell Gene Expression Atlas from the University of Tokyo (ImmuNexUT) cohort1. At enrollment, SLE patients had diverse clinical manifestations (disease activity, organ involvement and treatment profiles) and 22 patients were re-evaluated after belimumab treatment.

Results

We first profiled two distinct cell-type-specific transcriptomic signatures: disease-state and disease-activity signatures, reflecting disease establishment and exacerbation, respectively.

After confirming the high replicability of both signatures in independent cohorts, we identified candidates of biological processes unique to each signature: e.g., upregulated E2F transcriptional activity in Th1, CD8+ memory T-lineage and NK cells, and dynamic increase of IL21 and CXCL13 in Th1 cells in an active phase of SLE. Pathway analysis highlighted the importance of immunometabolic process for SLE (e.g., oxidative phosphorylation) in cell-type-specific resolution.

Moreover, we demonstrated cell-type-specific contributions to diverse organ involvement, e.g., Th1 for mucocutaneous, monocyte-lineage cells for musculoskeletal, neutrophil-lineage cells for renal activity, respectively.

We also observed the strong associations of disease-activity signatures with treatment effect: (i) belimumab suppressed activity signatures from B-lineage cells, especially in good responders and (ii) mycophenolate mofetil substantially suppressed activity signatures from plasmablast, Th1, and central memory CD8 cells.

However, through stratified LD score regression using large-scale SLE-GWASs, we revealed that disease-activity signatures were less enriched around SLE risk variants than disease-state signatures. Consistent with this result, the directions of SLE risk alleles’ expression quantitative trait locus (eQTL) effects were significantly concordant with the directions of disease-state signatures, but not with those of activity signatures. These findings suggested that the current genetic case-control studies may not well capture clinically vital biology linked to drug target discovery for SLE. Meanwhile, we also detected some examples of activity signatures that might contribute to the disease risk by modulating risk allele’s eQTL effects.

Figure 1.

Conclusion

We identified comprehensive gene signatures reflecting the establishment and exacerbation of SLE, which provide essential foundations for future genomic, genetic, and clinical studies.

References

[1]Ota, M. et al. Dynamic landscape of immune cell-specific gene regulation in immune-mediated diseases. Cell 2021;184:3006-21.e17.

Acknowledgements

This study was supported by Chugai Pharmaceutical Co., Ltd., Tokyo, Japan; the Ministry of Education, Culture, Sports; and the Japan Agency for Medical Research and Development (AMED) (JP21tm0424221 and JP21zf0127004).

Disclosure of Interests

Masahiro Nakano: None declared, Mineto Ota Grant/research support from: Mineto Ota belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yusuke Takeshima Grant/research support from: Yusuke Takeshima belonged to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yukiko Iwasaki: None declared, Hiroaki Hatano: None declared, Yasuo Nagafuchi Grant/research support from: Yasuo Nagafuchi belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kwangwoo Kim: None declared, So-Young Bang: None declared, Hye Soon Lee: None declared, Hirofumi Shoda: None declared, Xuejun Zhang: None declared, Sang-Cheol Bae: None declared, Chikashi Terao: None declared, Kazuhiko Yamamoto: None declared, Tomohisa Okamura Grant/research support from: Tomohisa Okamura belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kazuyoshi Ishigaki: None declared, Keishi Fujio Speakers bureau: Keishi Fujio receives speaker fees from Chugai Pharmaceutical., Consultant of: Keishi Fujio receives consulting honoraria from Chugai Pharmaceutical., Grant/research support from: Keishi Fujio receives research support from Chugai Pharmaceutical.

Long-term outcomes of an extracorporeal irradiated autograft for limb salvage operations in musculoskeletal tumours

Aims

We analyzed the long-term outcomes of patients observed over ten years after resection en bloc and reconstruction with extracorporeal irradiated autografts

Patients and Methods

This retrospective study included 27 patients who underwent resection en bloc and reimplantation of an extracorporeal irradiated autograft. The mean patient age and follow-up period were 31.7 years (9 to 59) and 16.6 years (10.3 to 24.3), respectively. The most common diagnosis was osteosarcoma (n = 10), followed by chondrosarcoma (n = 6). The femur (n = 13) was the most frequently involved site, followed by the tibia (n = 7). There were inlay grafts in five patients, intercalary grafts in 15 patients, and osteoarticular grafts in seven patients. Functional outcome was evaluated with the Musculoskeletal Tumor Society (MSTS) scoring system.

Results

There were no recurrences in the irradiated autograft and the autograft survived in 24 patients (88.9%). Major complications included nonunion (n = 9), subchondral bone collapse (n = 4), and deep infection (n = 4). Although 34 revision procedures were performed, 25 (73.5%) and four (11.8%) of these were performed less than five years and ten years after the initial surgery, respectively. The mean MSTS score at the last follow-up was 84.3% (33% to 100%).

Conclusion

Considering long-term outcomes, extracorporeal irradiated autograft is an effective method of reconstruction for malignant musculoskeletal tumours Cite this article: Bone Joint J 2019;101-B:1151–1159

Reduction of HIV persistence following transplantation in HIV-infected kidney transplant recipients

Chronic inflammation may contribute to human immunodeficiency virus (HIV) persistence through a number of potential pathways. We explored the impact of immunosuppressant therapy on peripheral blood measures of HIV persistence following kidney transplantation. Stored plasma and peripheral blood mononuclear cells prior to transplantation and at weeks 12, 26, 52 and 104 posttransplant were obtained from 91 transplant recipients. In a multivariate model, higher pretransplant plasma HIV RNA level (p < 0.0001) and a longer duration of follow-up posttransplant (p = 0.09) were associated with higher posttransplant plasma HIV RNA levels. A higher baseline HIV DNA (p < 0.0001) was significantly associated with higher HIV DNA levels posttransplant, while higher CD4+ T cell count (p = 0.001), sirolimus use (p = 0.04) and a longer duration of follow-up (p = 0.06) were associated with lower posttransplant HIV DNA levels. The association between sirolimus exposure and lower frequency of cells containing HIV DNA levels posttransplant suggest that the immune-modifying drugs may affect the level of HIV persistence during effect therapy. Future studies of sirolimus as a reservoir-modifying agent are warranted.

Electron paramagnetic resonance studies on spin-labelling of pepsin: effects of temperature, pH and urea on its conformation

Pepsin was spin-labelled with N-(1-oxyl-2,2,6,6-tetramethyl-4-piperidyl) bromoacetamide, possibly at the active site, at a beta-catboxyl group of a reactive aspartic acid. The spectrum of the spin-labelled pepsin showed that the spin probe was strongly immobilized (correlation time is greater than or equal to 10(-8) sec). Spin-labelled pepsin was thermally denatured at various temperatures and electron paramagnetic resonance (e.p.r.) spectra were taken at various times. Rates of denaturation estimated from the e.p.r. spectra at various temperatures showed that the enthalpy and entropy of thermal denaturation of spin-labelled pepsin at pH 3.5 were 48.0+/-4.9 kcal/mole and 214.7+/-14.5 e.u. respectively. Addition of conc. NaOH or 1 M acetate buffer at pH 6.0 sharpened e.p.r. spectra of the spin-labelled pepsin, indicating that the spin probe became mobilized by alkaline denaturation. Addition of urea caused unfolding of the protein which increased with the urea concentration, although only slight transition of conformational changes was observed in the e.p.r. spectra.

Periostin: novel diagnostic and therapeutic target for cancer

Periostin is a secreted protein that shares a structural homology to the axon guidance protein fasciclin I (FAS1) in insects and was originally named as osteoblast-specific factor-2 (Osf2). Periostin is particularly highly homologus to Betaig-h3, which promotes cell adhesion and spreading of fibroblasts. It has recently been reported that Periostin was frequently overexpressed in various types of human cancers. Although the detailed function of Periostin is still unclear, Periostin-integrin interaction through FAS1 domain is thought to be involved in tumor development. In addition, Periostin stimulates metastatic growth by promoting cancer cell survival, invasion and angiogenesis. Therefore, Periostin can be a useful marker to predict the behavior of cancer. This review summarizes the recent understanding of Periostin roles in tumor development and speculates on the usefulness of Periostin as a therapeutic and diagnostic target for cancer.

A ceramic prosthesis for the treatment of tumours of the distal radius

Despite extensive experience with prosthetic replacement for the reconstruction of limbs following juxta-articular resection of tumours, there are few reports of prosthetic replacement of the distal radius. We present two cases of massive bone defects of the distal radius in which alumina ceramic prosthetic replacements were used. We evaluated the patients more than ten years after the procedure. Both patients had degenerative changes to the wrist. This, however, was not associated with pain or decreased function, and both had returned to their previous occupation after surgery. When a patient has a massive defect of the distal radius, reconstruction using a ceramic prosthesis is a reasonable alternative to using autograft. This method of treatment results in little pain, a moderate range of movement and satisfactory function.

Periostin is frequently overexpressed and enhances invasion and angiogenesis in oral cancer

Oral squamous-cell carcinoma (OSCC) is one of the most common types of human cancer. Typically OSCC cells show persistent invasion that frequently leads to local recurrence and distant lymphatic metastasis. We previously identified Periostin as the gene demonstrating the highest fold change expression in the invasive clone by comparing the transcriptional profile of parent OSCC cell line and a highly invasive clone. Here, we demonstrated that Periostin overexpression enhanced invasiveness in oral cancer cell lines. To know the role of Periostin in invasion, angiogenesis and metastasis in OSCC cases, we first examined the expression of Periostin mRNA in 31 OSCC cases by RT-PCR and Periostin protein in 74 OSCC cases by immunohistochemistry. Then, we compared the Periostin expression with invasion pattern, metastasis and blood vessel density. Periostin mRNA and protein overexpression were frequently found in OSCC cases and Periostin expression was well correlated with the invasion pattern and metastasis. Moreover, blood vessel density of Periostin-positive cases was higher than those of Periostin-negative cases. Interestingly, recombinant Periostin enhanced capillary formation in vitro in a concentration-dependant manner. In summary, these findings suggest that Periostin may promote invasion and angiogenesis in OSCC, and that Periostin can be a strong marker for prediction of metastasis in oral cancer patients.

Macroscopic quantum tunneling in a d-wave high-TC Bi2Sr2CaCu2O8 + delta superconductor

While Josephson-junction-like structures intrinsic to the layered cuprate high temperature superconductors offer an attractive stage for exploiting possible applications to new quantum technologies, the low energy quasiparticle excitations characteristically present in these d-wave superconductors may easily destroy the coherence required. Here we demonstrate for the first time the feasibility of macroscopic quantum tunneling in the intrinsic Josephson junctions of a high temperature superconductor Bi(2)Sr(2)CaCu(2)O(8 + delta), and find it to be characterized by a high classic-to-quantum crossover temperature and a relatively weak quasiparticle dissipation.

Extracorporeal irradiated autogenous osteochondral graft

We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.

Treatment of myxoid liposarcoma by marginal or intralesional resection combined with radiotherapy

Local recurrence-free survival rate for myxoid liposarcoma (MLS) is related to negative surgical margins. The goal of surgery in the treatment of MLS is to obtain tumor-free surgical margins. When a tumor is adjacent to critical structures, wider resection, which can result in amputation, would be selected for local control. While recognizing that marginal or intralesional resection is associated with high risk of recurrence, circumstances occur that lead surgeons to conduct conservative surgery. To determine whether marginal or intralesional resection combined with radiotherapy can achieve local control, 10 cases (12 tumors) were reviewed involving MLS treated with marginal (8 tumors) or intralesional resection (4 tumors) followed by postoperative radiotherapy (50-70 Gy, average 59.2 Gy). No recurrences of MLS were observed locally at the mean follow-up of 58.1 months. The development of severe radiation-related complications was not detected. This medium follow-up study suggested that this method can achieve a high rate of local control.

Development of a cellular model to study alternative splicing of type II collagen gene

To study regulation of alternative splicing of type II collagen (COL2) pre-mRNA, we constructed a mouse COL2 "minigene" containing genomic sequences spanning exon 1 to exon 4 of COL2 downstream of a cytomegalovirus (CMV) promoter. This minigene was introduced into ATDC5 cells, which undergo chondrocytic differentiation when treated with insulin. Alternative splicing of the COL2 minigene was evaluated by comparing the expression of the two mRNAs transcribed from the minigene to the expression of alternatively spliced transcripts from the endogenous COL2 gene. This analysis suggested that regulation of alternative splicing of pre-mRNAs from the minigene and the endogenous COL2 gene are accomplished by similar mechanisms. We conclude that the cloned genomic fragment contains key sequences necessary for alternative splicing of COL2 pre-mRNA. This system provides a useful model to begin the process of identifying cis- and trans-acting factors that carry out alternative splicing of COL2 pre-mRNA during chondrocyte differentiation.

A PCR-ELISA assay for the detection of disseminated osteosarcoma cells in a mouse metastatic model

Circulating tumor cells in the blood play a central role in the metastatic process. There have been no reports describing the relationship between lung metastasis and circulating osteosarcoma cells. We developed a system with a polymerase chain reaction assay based on an enzyme-linked immunosorbent assay (PCR-ELISA) to detect circulating osteosarcoma cells in a mouse metastatic model. Osf2/Cbfa1, hereafter called Osf2, a member of the runt family of transcription factors, was used as a target gene. One splicing variant of Osf2 mRNA was identified and its expression was restricted to the bones and osteosarcomas. The amount of the splicing variant of Osf2 mRNA was significantly higher in the blood of mice with metastasis than in the blood of the control group. The PCR-ELISA using Osf2 mRNA is a potential method to detect circulating osteosarcoma cells in peripheral blood.

Structure-activity relationships of N-(3,5-dimethoxy-4-n-octyloxycinnamoyl)-N'-(3,4-dimethylphenyl)piperazine and analogues as inhibitors of acyl-CoA: cholesterol O-acyltransferase

A novel series of acyl-CoA: cholesterol O-acyltransferase (ACAT) inhibitors were synthesized from a lead compound, 1-(4-hydroxy-3-methoxyphenyl)-7-phenylhept-1-en-3-one (1, Yakuchinone B) through a modification of three regions (A, B, C) in the molecule. In this study, the compounds prepared were tested for in vitro inhibitory activity on microsomal ACAT from the liver of rats and for in vivo hypocholesterolemic activity in rats given a high cholesterol diet. N-(3,5-Dimethoxy-4-n-octyloxycinnamoyl)-N'-(3,4-dimethylphenyl)piperazine (45), which belongs to the amide compounds, has finally been discovered. Compound 45 inhibited rat hepatic ACAT in a more striking manner than CI-976, an amide compound ACAT inhibitor, and it exhibited a high level of hypocholesterolemic activity in vivo. Since 45 strongly inhibited both microsomal ACAT prepared from HepG2 (a cell line derived from human hepatocarcinoma) and Caco2 (a cell line derived from human colon adenocarcinoma), there is speculation that 45 might have the ability to inhibit ACAT in both the human intestine and liver independent of the difference in the distribution of ACAT isozymes. On the other hand, 45 did not induce adrenotoxicity in subacute toxicity studies in rats. These results suggest that it has promise for development as a new therapeutic agent for hypercholesterolemia and atherosclerosis.

Recurrent malignant variant of phosphaturic mesenchymal tumor with oncogenic osteomalacia

Phosphaturic mesenchymal tumor is a rare neoplasm which causes osteomalacia or rickets. The tumor typically follows a benign clinical course. Even in the rare malignant cases, local recurrence and distant metastasis are uncommon. We report on an example of a malignant phosphaturic mesenchymal tumor which recurred several times over 16 years concurrently causing hypophosphatemia, bone pain, and osteomalacia. Following each surgery, symptoms and hypophosphatemia improved. The patient died of disease 17 years after the first surgery. Histologically, the initial tumor was composed of small spindle cells with clusters of giant cells, prominent blood vessels, poorly formed cartilaginous areas, and crystalline material. Cytological atypia was minimal. Following multiple recurrences, the tumor demonstrated areas of high-grade sarcoma exhibiting marked pleomorphism, numerous mitotic figures, and p53 overexpression. This case illustrates the potential lethality of incompletely removed phosphaturic mesenchymal tumors.

Elevation of serum alkaline phosphatase in clear cell chondrosarcoma of bone

BACKGROUND

Clear cell chondrosarcoma is a rare bone tumor, which is sometimes misdiagnosed as a different bone neoplasm.

MATERIALS AND METHODS

The files of 6 patients with clear cell chondrosarcomas were reviewed. Histological slides, radiographic studies, and pre- and post-operative serum alkaline phosphatase (ALP) levels were evaluated. Molecular and histochemical analyses of ALP were documented in one case of clear cell chondrosarcoma.

RESULTS

Pre-operative serum ALP levels were elevated in 3 patients, and were normal in another 3 patients. After removal of the tumors, the enzyme levels decreased in all patients and returned to normal in 3 patients, who had pre-operative high ALP levels. Enzyme histochemical and molecular analyses demonstrated that the tumor produced ALP.

CONCLUSION

Clear cell chondrosarcoma produces ALP, which can be used as a tumor marker in diagnosis and follow-up.

In vivo bone-forming capacity of human bone marrow-derived stromal cells is stimulated by recombinant human bone morphogenetic protein-2

In the present study, we investigated whether the in vivo bone-forming capacity of human bone marrow-derived stromal cells (HMSCs) could be enhanced by recombinant human bone morphogenetic protein-2 (rhBMP-2). The HMSCs obtained from seven donors (5-54 years of age) were passaged three to six times. Passaged HMSCs exhibited the osteoblastic phenotype in vitro, including: (a) an increase in alkaline phosphatase (ALP) activity in response to dexamethasone, ascorbic acid, and beta-glycerophosphate: and (b) mRNA expression for markers of osteoblastic lineage (ALP, osteopontin, osteocalcin, and parathyroid hormone-receptor) and BMP-2, -4, and -6 detected by reverse transcription-polymerase chain reaction. For the in vivo assay, transplants were subcutaneously implanted into nude mice as follows: group A (vehicle); group B (rhBMP-2); group C (HMSCs with vehicle); and group D (HMSCs with rhBMP-2). Transplants were obtained 2 and 4 weeks after implantation. Correlated radiographic findings, histological observations, and in situ hybridization using species-specific probes showed that the group B transplants contained bone tissue of mouse origin, which was observed at the periphery of the transplants. Four weeks after implantation, small amounts of HMSCs-derived bone tissue were detected at the periphery in two of seven transplants in group C. In contrast, five of seven group D transplants exhibited HMSCs-derived bone tissue, which was located at the center of the transplants and was surrounded by mouse bone tissue. Furthermore, HMSCs-derived chondrogenesis was detected in two of seven group D transplants. The results of the present study demonstrate that culture-expanded HMSCs preserve the osteoblastic phenotype, and the in vivo bone-forming capacity can be promoted by rhBMP-2.

Epithelioid trophoblastic tumor metastatic to the vagina: an immunohistochemical and ultrastructural study

We describe an epithelioid trophoblastic tumor (ETT) metastatic to the vagina in a 30-year-old Japanese woman. A polypoid tumor in the vaginal orifice was composed of nests of intermediate trophoblastic cells that showed a striking epithelioid appearance. In the hysterectomy specimen, a tumor infiltrated through the myometrium and showed histologic findings similar to those of the vaginal tumor. The tumor cells were positive for cytokeratin, inhibin-alpha, and melanoma cell adhesion molecule (Mel-CAM, CD146) but were only focally positive for human placental lactogen. Electron microscopic examination revealed bundles of well-developed, intermediate-type filaments surrounding the nuclei.

Diarylheptanoids suppress expression of leukocyte adhesion molecules on human vascular endothelial cells

Diarylheptanoids possess potent anti-inflammatory properties. However, the mechanism of their action is not fully understood. In this study, we found that three diarylheptanoids, 1-(3, 5-dimethoxy-4-hydroxyphenyl)-7-phenylhept-1-en-3-one (YPE-01), yakuchinone B and demethyl-yakuchinone B, reduced the adhesion of both human monocytic cell line U937 and human eosinophilic cell line EoL-1 cells to tumor necrosis factor-alpha (TNF-alpha)-treated human umbilical vein endothelial cells. In addition, they suppressed interleukin-1beta- or TNF-alpha-induced expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on the surface of the endothelial cells. Since YPE-01 reduced both VCAM-1 and ICAM-1 mRNA induction in TNF-alpha-stimulated endothelial cells, diarylheptanoids appeared to suppress adhesion molecule expression at the transcriptional level. Furthermore, YPE-01 suppressed both VCAM-1 and ICAM-1 mRNA induction as well as edema in 12-O-tetradecanoylphorbol 13-acetate (TPA)-inflamed mice ears in vivo. These results suggest that the anti-inflammatory action of diarylheptanoids is, at least in part, due to their suppressive effect on the surface expression of inducible adhesion molecules in endothelial cells, and subsequent leukocyte adhesion.

Angle-multiplexed hologram storage in LiNbO(3):Tb, Fe

We have performed hologram multiplexing with a cw laser at lambda=532 nm in a near-stoichiometric LiNbO(3) :Tb, Fe crystal that exhibits a visible absorption band induced by UV light. When 50 plane-wave holograms were angle multiplexed from the UV preexposed state, the recording sensitivity gradually decreased, owing to bleaching of the induced absorption. However, a conventional recording schedule of multiplexing many holograms of equal diffraction efficiency can be used in this photochromic material. The gradual decrease in recording sensitivity throughout multiplexing can be compensated for by the increased erasure-time constants of later-written holograms. An M/# of 1.73 was obtained in a crystal of 3.3-mm thickness.

Metabolic and anthropometric consequences of interruption of highly active antiretroviral therapy

BACKGROUND

HAART has been associated with metabolic abnormalities (hyperlipidemia, insulin resistance, alterations in cortisol metabolism) and fat redistribution.

SETTING

A prospective study of 26 Caucasian men (median age 43.5 years) with HIV-1 viral loads < 500 copies/ml for 12 months while on highly active antiretroviral therapy (HAART) who interrupted treatment for a median of 7.0 weeks (range 4.9-10.3 weeks). Seventeen (65.4%) patients reported at least one fat redistribution symptom at baseline.

METHOD

Serum lipids, glucose and insulin levels during an oral glucose tolerance test, 24-h urinary free cortisol and 17-hydroxycorticosteroids, and anthropometric parameters were measured before HAART cessation and prior to its reinstitution.

RESULTS

When baseline values were compared with those obtained after HAART interruption (means +/- SD), there was a significant decrease in total cholesterol (194+/-47.3 versus 159+/-29.3 mg/dl; P < 0.0001), low density lipoprotein (LDL) cholesterol (114+/-32.6 versus 96+/-24.7 mg/dl; P = 0.0013), triglycerides (261+/-244.3 versus 185+/-165.4 mg/dl; P = 0.008), and 24-hour urinary 17-hydroxycorticosteroids (15+/-7.9 versus 5+/-2.5 mg/24 h, P < 0.0001) and a significant increase in 24-hour urinary free cortisol (45+/-34.1 versus 62+/-32.2 microg/24 h; P = 0.016). There were no significant changes in glucose or insulin levels or in anthropometric measurements.

CONCLUSIONS

A relatively brief interruption of HAART resulted in significant improvements in total cholesterol, LDL cholesterol, and triglyceride levels. No changes were observed in insulin resistance profiles or anthropometric measurements, perhaps because of the brief duration of HAART interruption. These results suggest that hyperlipidemia and alterations in corticosteroid metabolism in the setting of HAART are a direct drug effect that reverses with drug withdrawal. However, glucose metabolism and fat redistribution do not change over the short term.

[Effectiveness of DeVIC chemotherapy for recurrent primary central nervous system lymphoma]

Six cases with recurrent or refractory primary central nervous system lymphoma were treated with a new chemotherapeutic regimen "DeVIC (dexamethasone, VP16, ifosfamide, carboplatin)". Five recurrent cases had a remission period for an average of 18 months after initial treatment, but relapse occurred. One refractory case had no response after initial treatment. Then these 6 cases were treated with 1-3 courses of DeVIC chemotherapy at intervals of 4 weeks. Two cases achieved complete remission, and 3 cases attained partial remission (response rate was 83%). One case showed no response after 1 course of DeVIC chemotherapy. However, in all cases re-relapse occurred 1-5 months after remission, and only 1 case is still alive. DeVIC chemotherapy produced a high response rate for recurrent central nervous system lymphoma, but re-relapse occurred after only a few months. The establishment of maintenance chemotherapy is required.

Pre-HAART HIV burden approximates post-HAART viral levels following interruption of therapy in patients with sustained viral suppression

OBJECTIVE

To evaluate the relationship between the HIV viral burden in individuals prior to receiving highly-active antiretroviral therapy (HAART) and the viral burden after withdrawal of HAART.

DESIGN AND SETTING

Retrospective cohort study at the National Institutes of Health, Bethesda, Maryland, USA.

PATIENTS

Fourteen HIV-infected patients who achieved and maintained viral control on HAART who subsequently discontinued HAART.

MAIN OUTCOME MEASURES

Pre- and post-HAART viral loads measured from plasma or serum.

RESULTS

Patients achieved viral control (< 500 copies/ml) on HAART in a median 28 days (range, 15-490 days; mean, 72 days), maintained viral control for a median 661 days (range, 53-1067 days; mean, 611 days), and subsequently discontinued HAART for a median 49 days (range, 14-196 days; mean, 73 days). The median difference between the pre- and post-HAART viral loads was 0.16 log10 (range, -0.72 to 1.05 log10; mean, 0.19 log10). The median absolute difference between the pre- and post-HAART viral loads was 0.43 log10 (range, 0.06-1.05 log10; mean, 0.46 log10). Nine individuals had post-HAART values higher than pre-HAART values, five had lower values. Median duration between pre- and post-HAART viral load measurements was 1757 days (range, 117-3177 days; mean, 1756 days), or 4.8 years.

CONCLUSIONS

After discontinuing HAART, individuals had rebounds in their viral burdens approximating pre-HAART levels, even after a significant lapse of time approaching 5 years. Our data suggest that an intrinsic viral load set-point may exist, and that a single interruption of an effective regimen with viral suppression for almost 2 years does not significantly alter this set-point.

Strongyloides venezuelensis: heparin-binding adhesion substances in immunologically damaged adult worms

Immunologically damaged Strongyloides venezuelensis adult worms were examined for their mucosal invasion ability and secretion of heparin-binding adhesion substances. S. venezuelensis was expelled from male Wistar rats 4 to 5 weeks after infection. Four-week-old adult worms were smaller and had fewer eggs than 1-week-old adult worms. One-week-old, 4-week-old, and 5-week-old adult worms equally established in the recipient mouse intestine when surgically implanted. Adult worms of 4 and 5 weeks of age secreted adhesion substances as much as 1-week-old adult worms. There was no difference in the heparin-binding activities and the lectin-binding profile of adhesion substances among adult worms of different ages. The rate of secretion of adhesion substances from the mouth was also identical. Heparin-binding activities were detected in crude adult worm proteins; however, proteins of 5-week-old adult worms had weaker heparin-binding activities than those of 1-week-old adult worms. Western blotting revealed that a number of heparin-binding proteins were lost in 5-week-old adult worms. A heparin-binding protein of 42. 0 kDa, which was consistently expressed in adult worms, was a possible component of heparin-binding adhesion substances which are secreted from the mouth.

Quasinondestructive holographic recording in photochromic LiNbO3

We have observed quasinondestructive holographic storage with a continuous-wave laser at lambda = 532 nm in near-stoichiometric LiNbO3 doped with Tb and Fe. This crystal showed an exceptionally long grating decay time and also exhibited a fast color change upon exposure to ultraviolet (UV) light. It was demonstrated that the grating recorded from the UV-exposed, colored state can be continuously read out over 9 h at a reading intensity as high as 8 mW/cm(2). In addition, the written grating could be easily erased with UV illumination which returned the crystal back to the original colored state.

Spatiotemporal change of rat collagenase (MMP-13) mRNA expression in the development of the rat femoral neck

The interepiphyseal region between the greater trochanter and the capital femoral epiphysis and the medioproximal portion of the femoral neck exhibit extensive morphological changes during the first 4 weeks after birth in rats. Previous reports show that matrix metalloproteinase-13 (MMP-13, rat collagenase) mRNA is expressed in bone and cartilage during embryonal development and fracture healing. We examined MMP-13 mRNA expression and compared it with the distribution of osteopontin and osteocalcine mRNA in the femoral neck. Moreover, we examined histomorphometric analysis in the femoral neck where the morphology changes rapidly. Histomorphometric analysis of the 4-week-old rat femoral neck showed a high rate of bone formation and resorption in the region where shape changed rapidly. Osteopontin mRNA was expressed diffusely along the endosteum. In contrast, MMP-13 mRNA expression was restricted to the medial endosteal portion near the cartilage-bone interface of the femoral neck in 15- and 28-day-old rats and in the deepest endosteal interepiphyseal region of 15-day-old rats. MMP-13 mRNA-expressing osteoblastic cells were also expressing osteopontin but not osteocalcin mRNA. MMP-13 mRNA-expressing cells differ from tartrate-resistant acid phosphatase (TRAP)-positive cells, and MMP-13 mRNA-positive cells are located adjacent to TRAP-positive cells. The results of the site- and cell-specific expression of MMP-13, taken together with its enzymatic property, suggest that MMP-13 plays an important role in morphological changes in the rat femur, at least during the third and fourth week after birth, and that MMP-13 itself is involved in the interaction between osteoblastic and TRAP-positive cells.

Expression of metalloproteinase-13 (Collagenase-3) is induced during fracture healing in mice

In fracture healing, a large amount of cartilage is formed, then rapidly replaced by osseous tissue. This process requires the transition of extracellular matrix component from type II to type I collagen. We investigated the expression of matrix metalloproteinase-13 (MMP-13), which has a high potential to cleave type II as well as type I collagen, during fracture repair in mouse ribs. In situ hybridization demonstrated that MMP-13 mRNA was present throughout the healing process. It was detected in the cells of the periosteum at day 1. As fracture callus grew, strong MMP-13 mRNA signals were detected in cells of the cartilaginous callus. In the reparative and remodeling phases, both hypertrophic chondrocytes and immature osteoblastic cells in the fracture callus expressed MMP-13 mRNA strongly. These cells were located adjacent to tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts at the sites of cartilage/bone transition. In osteoclasts, MMP-13 expression was not detected. The level of MMP-13 mRNA peaked at day 14 postfracture by northern blotting. Immunohistochemical staining showed that MMP-13 was detected primarily in hypertrophic chondrocytes. These results indicate that MMP-13 is induced during fracture healing. The site- and cell-specific expression of MMP-13 and its enzymatic property suggest that MMP-13 initiates the degradation of cartilage matrix, resulting in resorption and remodeling of the callus. In conclusion, MMP-13 plays an important role in the healing process of fractured bone in mice.

Applicability of deconvolution and nonlinear optimization for reconstructing optical images from near-field optical microscope images

We have made a computer reconstruction of a nanometric optical image of a sample from an observed near-field optical image. The near-field microscope image used for investigation was obtained numerically in three dimensions with the finite-difference time-domain (FDTD) method. The sample is dielectric substrate containing nanometric two strips made of dielectric or metal. Deconvolution with non-negativity constraint is used to reconstruct the nanometric structure of dielectric strips, while nonlinear optimization is used to reconstruct the metallic strips. The difference in choice of reconstruction method between two samples comes from the difference in degree of interaction or multiple scattering of the sample structure and the probe. It is shown in the results, the resolution limit attainable in deconvolution is as fine as the size of aperture of probe.

[Evaluation of restenosis after percutaneous transluminal coronary angioplasty using a Doppler index, the Tei index]

Cardiac function and restenosis were evaluated after percutaneous transluminal coronary angioplasty (PTCA) using a Doppler index (the Tei index). Thirty-eight patients, 31 men and 7 women (mean age 57 years) with ischemic heart disease were studied. The underlying heart diseases were angina pectoris without left ventricular asynergy in 16 patients and old myocardial infarction (OMI) with left ventricular asynergy in 22 . Ejection fraction was measured by M-mode echocardiography and deceleration time, and the interval between cessation and onset of the mitral inflow velocity (a), ejection time at aortic valve (b), and the Tei index [(a-b)/b] were measured by M-mode echocardiography performed before and 6 months after PTCA. The ejection fraction, deceleration time and Tei index showed no changes after PTCA in patients with angina pectoris with or without restenosis. In patients with OMI with restenosis, the Tei index increased slightly after PTCA, from 0.56 +/- 0.15 to 0.61 +/- 0.13. The deceleration time changed from 0.23 +/- 0.03 to 0.24 +/- 0.02 msec, and the ejection fraction from 0.46 +/- 0.11 to 0.51 +/- 0.17, neither significantly. However, in patients with OMI without restenosis (15 out of 22 patients), the Tei index significantly improved after PTCA, from 0.55 +/- 0.13 to 0.48 +/- 0.12 (p < 0.05). In patients with left ventricular asynergy due to old myocardial infarction, without restenosis, the Tei index significantly improved after PTCA. The Tei index is useful for evaluating restenosis after PTCA in patients with OMI.

Differences in umbilical cord serum lipid levels with mode of delivery

OBJECTIVE

To investigate whether umbilical cord serum lipid levels differ with mode of delivery.

DESIGN

Retrospective observation study.

POPULATION

Two hundred and ninety mothers aged 29.1 years (SD 4.7) who had vaginal delivery, and 44 mothers aged 30.4 years (SD 4.7) who had elective caesarean section were enrolled.

MAIN OUTCOME MEASURES

Maternal and umbilical cord blood were obtained immediately after delivery. Serum lipid levels including total cholesterol, high density lipoprotein cholesterol, saturated fatty acid, mono-unsaturated fatty acid and polyunsaturated fatty acid were measured. Obstetric variables and serum lipid levels were compared between the two groups. In each group the correlations of fetal serum lipid levels with maternal serum lipid levels were investigated.

RESULTS

There were no significant differences in maternal age, neonatal weight, gestational duration, placental weight and neonatal gender distribution between the two groups. Only the two fetal serum lipid levels (including total cholesterol and non-high density lipoprotein cholesterol) showed a correlation with maternal fetal lipid levels with correlation coefficients > 0.3 in the caesarean section group. However, saturated fatty acid, mono-unsaturated fatty acid and total fatty acid levels in the non-high density lipoprotein low density lipoprotein, very low density lipoprotein, intermediate density lipoprotein and free fatty acid fraction in the umbilical cord serum were significantly higher in the vaginal delivery cases (P < 0.01).

CONCLUSIONS

Umbilical cord serum levels of saturated and mono-unsaturated fatty acids increase during vaginal delivery.

Asthma-like disease in the children living in the neighborhood of Mt. Sakurajima

We conducted self-administered questionnaire surveys of school children living in the vicinity of Mt. Sakurajima using ATS-DLD questionnaire. In this paper, we report the results of analysis comparing the proportion of children with asthma-like disease in the area exposed to the volcanic ash and gases released by Mt. Sakurajima and control areas. Asthma-like disease was ascertained using ATS-DLD questionnaire and the definition proposed by the study group established by Environmental Protection Agency in Japan. The proportion of children with asthma-like disease was not different between the exposed and control groups. The odds ratio of asthma-like disease comparing the exposed and control groups was 1.1 and its 95% confidence interval was 0.7-1.8 (P = 0.583). When the exposed area was divided into Tarumizu city. Sakurajima town and Kagoshima city, none of them showed an elevated proportion of children with asthma-like disease when compared with the control area. In the entire study population including both the exposed and control groups, the proportion of children with asthma-like disease was 6 and 3% in boys and girls, respectively. These values were quite similar to those obtained from a survey of 45,674 school children in western districts in Japan in 1992. In conclusion, the present study indicates that the proportion of children with asthma-like disease is not elevated in the exposed area. Further investigations are necessary to confirm our conclusions.

In vivo drug release behavior in dogs from a new colon-targeted delivery system

The colon-targeted delivery capsule (CTDC), a new capsule-type dosage form for colonic delivery of drugs, was investigated for the in vivo drug release behavior in dogs. A CTDC formulation with prednisolone as a model drug and theophylline as a marker substance for gastric emptying was prepared for this study. The enteric-coated capsule (ECC) formulation with a similar composition was also prepared as the reference. Both formulations were administered to four beagle dogs, and the drug release behavior thereof was compared. Under fasted condition, ECC released prednisolone and theophylline at the same time within 1 h after the gastric emptying. On the other hand the CTDC released prednisolone at 3.2 h after the gastric emptying. Such release behavior of CTDC was approximately consistent with the results obtained from the in vitro dissolution study, suggesting that the pH-sensing and timed-release functions imparted to the CTDC can work in the gastrointestinal tract of dogs as programmed. Under non-fasted condition, however, the gastric emptying of CTDC was found to be considerably delayed, up to about 14 h, and in this case the in vivo dissolution lag time of prednisolone at the small intestine was shortened to about 1.5 h.

Origin of histiocyte-like cells and multinucleated giant cells in malignant fibrous histiocytoma: neoplastic or reactive?

The origin of histiocyte-like cells in malignant fibrous histiocytoma (MFH) remains controversial. To determine whether histiocyte-like cells and multinucleated giant cells show reactive or neoplastic proliferation, we transplanted human storiform-pleomorphic MFH to nude mice and investigated the origin of histiocyte-like cells using the DNA in situ hybridization (ISH) system. In addition, we analyzed the mRNA expression of mouse c-fms and human colony stimulating factor-1 (CSF-1); immunohistochemical expression of markers detectable in cells of monocyte/macrophage lineage. The DNA ISH revealed neoplastic proliferation of fibroblastic cells and bizarre multinucleated giant cells of human origin. Monocyte/macrophage lineage cells were seen in parental tumors, whereas they did not participate in neoplastic proliferation in transplanted tumors. The parental tumors expressed human CSF-1 mRNA and the histiocyte-like cells in transplanted tumors expressed 'mouse' c-fms mRNA. These results suggest that MFH induce infiltration of monocyte/macrophage and CSF-1 is one of the mediators involved in this phenomenon, because the human CSF-1 can act as a ligand to the mouse c-fms. Histiocyte-like cells in MFH should be considered as a reactive monocyte/macrophage lineage rather than as an element of neoplasm.

Stoichiometric Mg:LiNbO(3) as an effective material for nonlinear optics

Photorefractive damage, optical absorption, photoconductivities, and photogalvanic currents of stoichiometric LiNbO(3) single crystals with different Mg doping levels have been investigated. Nominally pure stoichiometric LiNbO(3) shows lower photorefractive damage resistance than congruent crystal; however, stoichiometric crystals doped with MgO of more than 1.8 mol. % exhibit no measurable photorefractive damage at 532 nm to intensities of as much as 8 MW/cm(2) . This remarkable damage resistance can be attributed not only to increased photoconductivity but also to decreased photogalvanic current. Stoichiometric Mg:LiNbO(3) also demonstrates the shortest absorption edge, 302 nm, and a single-domain nature with low scattering losses.

Origin of bone-forming cells in human osteosarcomas transplanted into nude mice--which cells produce bone, human or mouse?

Osteosarcomas are malignant tumours producing osteoid and/or bone. It is difficult to distinguish tumour bone formation from reactive, based on their morphological features alone. The objective of this study was two-fold: to clarify the origins of bone-forming cells in human osteosarcoma transplanted into nude mice; and to examine the role of bone morphogenetic proteins (BMPs) in the tumour-induced osteogenesis. DNA in situ hybridization was carried out with digoxigenin (DIG) polymerase chain reaction (PCR) labelled DNA probes for human-specific 'Alu' and mouse-specific 'mouse L1 (m-L1)' genes. Human osteosarcoma cells, established cell lines of NOS-1, NOS-2, and HuO9, were transplanted separately into nude mice. Bone-forming cells of the bone in the NOS-1 or NOS-2 tumours were positive for Alu, while they were negative for m-L1. The cells lining the surface of trabeculae in the HuO9 tumour were positive for Alu, but a few of them were also positive for m-L1. The m-L1-positive cells expressed mouse osteocalcin and type 1 collagen mRNAs. These facts suggest that the mouse cells were involved in osteoid synthesis of the HuO9 tumour. The NOS-1 or NOS-2 tumours expressed human BMP 2-7 mRNAs, whereas the HuO9 tumour expressed human BMPs 2, 4, 5, and 7. The osteogenetic potential of the tumours may depend on the expression patterns of BMPs. These results demonstrate two distinct types of bone formation, by tumour cells and by an admixture of tumour and non-tumour cells. The present study showed that the HuO9 tumour produces chimeric bone formation. This is the first report to demonstrate the relationships between tumour cells and non-tumour cells in bone formation, using genetic markers.

Reciprocity calibration of impulse responses of acoustic emission transducers

By means of reciprocity calibration in Rayleigh-wave and longitudinal-wave sound fields, frequency characteristics of amplitude and phase of absolute sensitivity of acoustic emission transducers were measured on the basis of the newly derived complex reciprocity parameters, and the impulse responses were obtained through inverse Fourier transform. Calibration results were confirmed with supplemental experiments in which the fracturing of a pencil lead was utilized for the source of elastic waves. Impulse responses of acoustic emission transducers to both the Rayleigh-wave and longitudinal-wave displacement velocities were determined by means of purely electrical measurements without the use of mechanical sound sources or reference transducers.

The sex differences in cord-blood cholesterol and fatty-acid levels among Japanese fetuses

We examined serum cholesterol and fatty-acid levels of cord blood and maternal blood samples collected from 193 Japanese fetuses and their mothers. Our study, which is the largest study of this kind ever conducted in Japan, is the first Japanese study reporting that total, high density lipoprotein (HDL) and non-HDL cholesterol levels in females were statistically significantly higher than those in males; the sex differences of total, HDL and non-HDL cholesterol levels were 8.5 mg/dl (P = 0.002), 4.5 mg/dl (P = 0.004) and 4.1 mg/dl (P = 0.045), respectively. The sex difference of total cholesterol was attributable to both HDL and non-HDL cholesterol. The sex of fetuses didn't show evident differences in cholesterol levels in maternal sera. Fatty-acid levels in cord blood were also higher in female fetuses than in male fetuses. However, none of the differences except for monoene fatty acids were statistically significant. Further investigations seem warranted to elucidate the mechanisms involved in our results.

Near-field optical microscope with a multiheight scanning imaging mode

A near-field scanning optical microscope has been developed to yield optical images with various gap distances between the probe and the sample surface. The microscope uses an apertureless metallic probe, the position of which is controlled by regulation of the tunneling-electron current from the probe to the sample and by computer-generated bias voltage. Experimental results of near-field optical imaging with the developed microscope at different gap distances are shown. Thirteen images at gap distances of 0 to 500nm demonstrate that the near-field image depends strongly on the gap distance. The imaging characteristics of a near-field imaging system are shown with the spatial-frequency spectra of images. Future investigation of the developed microscope is also discussed.

Apoptosis in cultured human colon cancer cells induced by combined treatments with 5-fluorouracil, tumor necrosis factor-alpha and interferon-alpha

Biochemical analysis using nick end-labeling was performed to investigate the effect of various combinations of 5-fluorouracil, natural human tumor necrosis factor-alpha and natural human interferon-alpha on the induction of apoptosis in RPMI 4788 human colon cancer cells. After treatment with 5-fluorouracil (1 mM) for 48 h, the number of nick end-positive cells was significantly increased in comparison to the situation without treatment. When tumor cells were treated with 1 mM 5-fluorouracil, 2.86 Japan Reference Units (JRU)/ml natural human tumor necrosis factor-alpha and 1 x 10(3) IU/ml natural human interferon-alpha in combination for 48 h, the number of nick end-positive cells was significantly higher than that after treatment with 5-fluorouracil alone. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay revealed a significant decrease of relative viability, as compared to treatment with 5-fluorouracil (1 mM), 5-fluorouracil + natural human tumor necrosis factor-alpha, or 5-fluorouracil + natural human interferon-alpha for 48 h. Pretreatment with 5-fluorouracil (1 mM) for 24 h prior to treatment with natural human tumor necrosis factor-alpha (2.86 JRU/ml) and natural human interferon-alpha (10(3) IU/ml) for 24 h resulted in a significant increase of nick end-positive cells compared to pretreatment with natural human tumor necrosis factor-alpha and natural human interferon-alpha prior to treatment with 5-fluorouracil for 24 h (p < 0.05). These results suggest that 5-fluorouracil alone can induce apoptosis in RPMI 4788 tumor cells and that this effect can be enhanced by combination with natural human tumor necrosis factor-alpha and natural human interferon-alpha.

Periosteal chondrosarcoma invading the medullary cavity

We present a case of periosteal chondrosarcoma of the femur, in which a tumor invaded the medullary cavity and the lesion was clearly demonstrated only on MRI. To the best of our knowledge, there have been no previous reports of an intramedullary lesion caused by periosteal chondrosarcoma demonstrated on MRI.

Effectiveness and toxicity screening of various absorption enhancers in the large intestine: intestinal absorption of phenol red and protein and phospholipid release from the intestinal membrane

The effectiveness and local toxicity of absorption enhancers on the absorption of phenol red (PR) from the large intestine of rats were examined using an in situ loop method. The absorption enhancers used in this study were sodium glycocholate (GC-Na), sodium taurocholate (TC-Na), sodium deoxycholate (DC-Na), EDTA, sodium salicylate (Sal-Na), sodium caprate (Cap-Na), diethyl maleate (DM), N-lauryl-beta-D-maltopyranoside (LM) and mixed micelles (MM), all used at a concentration of 20 mM. Local toxicity was also investigated by assessing protein and phospholipid release as biological markers. DC-Na and MM were the most effective absorption enhancers, but they caused considerable release of proteins and phospholipids. GC-Na, TC-Na and LM, which caused little or only slight membrane damage, promoted PR absorption. Sal-Na, DM and EDTA did not enhance PR absorption. Overall, a correlation exists between the area under the curve of PR and protein and phospholipid release in the presence of absorption enhancers. However, GC-Na, TC-Na and LM promoted the absorption of PR with low toxicity. From these results, we concluded that GC-Na, TC-Na and LM are effective absorption enhancers which have low levels of toxicity at a concentration of 20 mM.

Genetic controls of susceptibility and resistance to 4-nitroquinoline 1-oxide-induced tongue carcinomas in rats

We analyzed the incidence of infiltrative mass-type tongue carcinomas (IMTC) induced in 550 rats by continuous oral administration of 0.001% 4-nitroquinoline 1-oxide solution for 180 days. The study included various crosses of susceptible Dark-Agouti rats (DA) and resistant Wistar/Furth rats (WF). DA showed a 93.6% incidence of IMTC measuring more than 5 mm in their largest diameter, while WF showed only a 4% incidence. Reciprocal F1 and F2 hybrids mated by DA and WF showed 47.5% and 45.8% incidences, respectively. Meanwhile, reciprocal backcrossed hybrids to DA and WF showed 73.7%, and 24.6% incidences, respectively. Segregation of the incidences suggests that there are two autosomal dominant genes, one linked to the susceptibility of DA and the other to the resistance of WF.