Expression of DOK1, 2, and 3 genes in HTLV-1-infected T cells.

Human T-cell leukemia virus type 1 (HTLV-1) can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATLL). The Tax protein encoded by the pX region of the HTLV-1 genome appears to be a key element in the early stage of ATLL development. In this study, we examined the expression of the downstream of tyrosine kinase (DOK) family members DOK1, DOK2 and DOK3, recently reported to be tumor suppressors, in HTLV-1-transformed T cells (MT-2 and HUT-102) and TL-Om1 cells derived from ATLL leukemic cells. DOK2 and DOK3 expression was significantly reduced in MT-2, HUT-102, and TL-Om1 cells compared with their expression in uninfected T cells, and the expression of DOK3 was reduced by the induction of Tax expression in T cells.

Differentiation of mouse hepatitis virus genotypes by restriction fragment length polymorphism analysis.

Reverse transcriptase-polymerase chain reaction (RT-PCR) amplification of the nucleocapsid (N) gene of mouse hepatitis virus (MHV) successfully detected 36 strains from the faeces of mice that had been housed in animal facilities in Japan from 2000 to 2003. Subsequent restriction fragment length polymorphism (RFLP) analysis, using the enzymes Acc I, Alu I, EcoR I and Mbo I, demonstrated that these strains could be divided into five distinct subgroups and that the same MHV strains were detected from closely related mouse facilities. Furthermore, strains from the same facility showed the same RFLP pattern, irrespective of the year of detection, but this pattern varied between different locations. This study shows that RFLP analyses are a rapid and useful method for differentiation of MHV strains.

Transmission of human T-cell leukaemia virus type I into adult mice.

Human T-cell leukaemia virus type I (HTLV-I)-transformed rabbit T-cells, F647a, were intraperitoneally injected into eight 10-week-old C3H/He and C3H/HeJ mice (1 x 10(7) F647a cells/mouse), respectively. Antibody titres against HTLV-I increased to a peak at 1-3 months after injection in both C3H/He and C3H/HeJ mice. At 12 months after injection, antibody titres of two of the eight C3H/HeJ mice became undetectable, whereas those of all the C3H/He mice still ranged from 1:10 to 1:40. Sera from both seropositive C3H/He and C3H/HeJ mice reacted with HTLV-I core proteins, but not with the env protein. HTLV-I proviral sequences were detected in two of eight C3H/He mice and three of the eight C3H/HeJ mice. These results suggest that HTLV-I is able to infect an adult mouse.

HTLV-I infections in offspring derived from HTLV-I carrier rats during the suckling period.

An experimental rat model for vertical transmission of human T cell leukemia virus type I (HTLV-I) was used to examine whether the infection of offspring derived from HTLV-I carrier rats could be established during the suckling period. MT-2 (2 x 10(7)) cells were injected into 5-week-old rats twice, at 2-week intervals. HTLV-I infected or non-infected female rats were mated with HTLV-I carrier male rats. The titer of serum antibodies against HTLV-I in the offspring derived from non-infected dams was less than 1:16 by the agglutination test during the suckling period. The serum antibodies of the offspring derived from the infected dams was less than 1:32 at 1 day after birth and increased steadily to 1:2048 at 14 days. However, the HTLV-I proviral sequences were not detected in any organs of the offspring during the suckling period as determined by the nested double polymerase chain reaction (PCR). These findings indicate that maternal antibodies against HTLV-I were not readily transmitted through the placenta and that the anti-HTLV-I antibodies in the offspring came from the milk of the dams. Furthermore, the HTLV-I infection in the offspring that was derived from the carrier dam may not be established during the suckling period but after weaning.

Translocation of bacteria from the gastrointestinal tract in immunodeficient mice.

Host defence mechanisms associated with the inhibition of translocation of bacteria from the gastrointestinal (GI) tract were investigated in SCID and beige mice after decontamination with oral antibiotics and colonization with Escherichia coli C25. SCID mice, which have impaired T and B cell function, tended to have a greater incidence of bacterial translocation from the GI tract up to 7 days after inoculation compared with controls. However, after 7 days both SCID and controls cleared the E. coli C25 from the liver, spleen, blood and peritoneal cavity. Beige mice, with impaired NK cell and polymorphonuclear leukocyte function, were not able to clear the inoculated bacteria from their liver by 14 days after inoculation although the controls were cleared by 7 days. Numbers of bacteria in the mesenteric lymph nodes (MLN) of beige mice did not decrease significantly by 14 days after inoculation, whereas numbers in SCID mice decreased markedly within 7 days. These results suggest that defence mechanisms other than T and B cell function are important in the inhibition of systemic infection from the GI tract.

Engraftment of HTLV-I-transformed human T-cell line into SCID mice with NK cell function.

HTLV-I-transformed human T-cell line, MT-2, has been reported to successfully proliferate in only the SCID mice with depletion of NK cell function. However, MT-2 cells could be engrafted into SCID mice possessing normal NK cell function in this study. MT-2 cells (5-7 x 10(7) cells) were intraperitoneally injected into SCID mice without the deletion of NK cell function. The SCID mice developed tumors in the peritoneal cavities 3 months after the inoculation of MT-2 cells. All tumors reacted to anti-HTLV-I p19 and anti-HLA-DR monoclonal antibodies by immunofluorescence assay and were also positive for the HTLV-I gene by PCR assay. DNA obtained from main organs in group of mice with or without tumors showed a high incidence of positive signals for HTLV-I gene by PCR assay.

Functional oligomerization of purified human papillomavirus types 16 and 6b E7 proteins expressed in Escherichia coli.

Purified non-fused soluble human papillomavirus type 16 and 6b E7 proteins expressed in Escherichia coli were found to form oligomers. For both proteins, several degrees of oligomerization were demonstrated by gel filtration, dynamic laser light scattering and scanning electron microscopy. Oligomerization was dependent on the concentration of E7 protein. Oligomerized E7 proteins were able to bind the retinoblastoma gene product pRB and stimulated DNA synthesis when introduced into cells.

[Study of uneven pulmonary ventilation by sequential bolus method].

We report a new method of measuring the sequential ventilation associated with the primary mechanism for ventilation inhomogeneity. Four types of sequential curves were examined using simultaneous washouts of multiple tracer boluses inhaled from residual volume (RV) and at volumes above RV. The factors that affected the classification of curves were analyzed by the theory of quantification from the statistical data of blood gases, lung function tests, X-ray and clinical diagnosis. This method was applied to evaluate the ventilation distribution in 100 patients with pulmonary disease. It provided clinical information on certain types of disease which cannot be detected by traditional lung function tests. Sequential bolus method may permit determination of whether the disease has predominantly intra or inter-regional inhomogeneity.

Isolation of Acinetobacter calcoaceticus from the gastrointestinal tracts of SCID mice.

Acinetobacter calcoaceticus colonization was observed in the gastrointestinal tracts of C.-B17-scid/scid (SCID) mice, while it was not observed in C.B17-scid/+ and C.B17-+/+ mice with normal immunity housed under the same conditions. A. calcoaceticus and other viable enteric bacteria were not isolated from any organs other than gastrointestinal tract in SCID mice. The mice colonized with this organism were apparently healthy and no significant visceral lesion was observed.

[Intra-bullous ventilation of giant bulla: does slow ventilation space on multi-breath nitrogen washout test mean that giant bulla is present?].

Intra-bullous ventilation and uneven ventilation in patients with giant bulla were studied by the multi-breath nitrogen washout and 133Xe washout tests. Fourteen patients underwent the nitrogen washout test before and after bullectomy; 2 of them also underwent the 133Xe washout test before surgery. After bullectomy, pulmonary nitrogen clearance delay and alveolar dilution rate (ADR) of slow ventilation space improved significantly (p less than 0.01) from 202.5% to 51.5%, and from 0.98 to 0.95, respectively. The dilution rate of 133Xe in the bullous region, based on the 133Xe clearance curve, showed the same values as the nitrogen washout test. Therefore, we considered that bullous ventilation could be estimated by the ADR of the nitrogen washout test and that uneven ventilation resulted from the ADR difference between the giant bulla and the nonbullous lung. When the nonbullous lung region was emphysematous, however, it was impossible to estimate the intra-bullous ventilation from the nitrogen washout test.

Prediction of postoperative performance status in patients with giant bulla.

To predict the postoperative improvement in performance status after bullectomy, preoperative pulmonary function and dyspneic grade were evaluated in 20 patients with giant bulla. The patients were divided into two groups, based on postoperative performance status: group 1 consisted of 15 patients with improved status after surgery; and group 2 of five patients with worsened status after temporary improvement. To determine correlation with the groups, preoperative functional measurements such as %VC, FEV1%, MMF, PEFR, RV/TLC, delta N2, LCI, and PNCD were then analyzed by the multivariate statistic method; results of delta N2 and FEV1% showed significant correlation with the groups. Prediction of the groups based on the two measurements agreed with the actual results except in one patient. These results show that postoperative improvement in performance status of patients with giant bulla can be predicted on the basis of preoperative pulmonary function.

Effect of age on bacterial translocation from the gastrointestinal tract in mice.

To clarify the effects of age on bacterial translocation from the gastrointestinal tract, mice at the age of 1, 2, 4, 6, 12, and 15 months were antibiotic-decontaminated for 4 days and then inoculated orally with streptomycin-resistant Escherichia coli C25. Mice treated with cyclophosphamide and untreated controls were tested for bacterial translocation to the mesenteric lymph nodes (MLN) 2 days later. The population levels of E. coli C25 in cyclophosphamide-treated and untreated mice were approximately 10(9.3) and 10(9.5) per gram of cecum, respectively, at each tested age. There were no significant differences in the incidence of translocation of E. coli C25 to MLN at any of the tested ages, whereas the number of E. coli C25 detected in MLN was higher in young mice than in aged mice in both the cyclophosphamide-treated and untreated groups. These findings suggest that bacterial translocation from the GI tract may be a more important problem in young animals than in aged animals.

[Study of influence of respiratory rate to airway resistance in patients with pulmonary emphysema].

Application of the panting method is very difficult for patients with pulmonary emphysema (PE). We attempted to measure airway resistance (Raw) during quiet breathing and changing respiratory rate step by step in patients with PE using a pressure-type body plethysmograph system (BX-82) correcting measured values by temperature and humidity. Influence of the respiratory rate to Raw was studied at 0.5l/sec of inspiratory and expiratory flow. Whenever the respiratory rate was going up, the Raw increased in spite of the increase of the thoracic gas volume. Raw (2Hz) was about one and a half times as high as Raw (quiet breathing). On the other hand, when the respiratory rate was going up, elevation of the peak flow was always able to be recognized. It seemed that the state of the airway varied during the panting method. The Raw measured during 0.5 Hz breathing (nearly quiet breathing) had small variability. Because the airway state during 0.5 Hz breathing was nearly the same as that during quiet breathing, measurement of Raw (0.5Hz) can be regarded as a practical method in patients with PE.

Bacterial translocation from the gastrointestinal tract in various mouse models for human diabetes.

Bacterial translocation from the gastrointestinal (GI) tract to other internal organs was examined in multiple low-dose streptozotocin-injected (M-STZ), single large-dose streptozotocin-injected (S-STZ), alloxan-injected (Alloxan), and non-obese diabetic (NOD) mice. The incidence of bacterial translocation from the GI tract to the tested organs among diabetic mice was in the order of M-STZ mice greater than S-STZ mice greater than NOD, Alloxan, and control mice. The injections of insulin to M-STZ mice did not decrease the incidence of translocation. These results suggest that bacterial translocation from the GI tract in diabetic mice is not induced by diabetes.