When mice were exposed to restraint stress for 12 or 24 h, severe lymphopenia was induced in all immune system organs, including the liver and the thymus. However, in adrenalectomized mice, this response was completely absent. Phenotypic characterization revealed that interleukin (IL)-2Rbeta+CD3int cells (i.e. extrathymic T cells) with CD4+ phenotype and the NK1.1+ subset of CD3int cells (i.e. NKT cells) in the liver as well as the mature conventional T cells in the thymus were resistant to such stress. In adrenalectomized mice, there was no significant change in the distribution of lymphocyte subsets in all tested organs before stress. Interestingly, the number of lymphocytes in the liver and spleen and the proportion of NKT cells in the liver rather increased after stress in these adrenalectomized mice. Therefore, endogenous steroid hormones were indicated to be important in the induction of immunosuppressive states after stress. Among stress associated cytokines, the secretion of tumour necrosis factor (TNF)-alpha was completely suppressed while that of IL-6 was partially suppressed in adrenalectomized mice. These results suggest that endogenous steroid hormones are important for the induction of the stress associated immunosuppression and that NKT cells are resistant to stress, namely, resistant to exposure to endogenous steroid hormones.

ABSTRACT. In answer to Ko's question raised in 1983, we show that an initial value problem given by a polynomial-time computable, Lipschitz continuous function can have a polynomial-space complete solution. The key insight is simple: the Lipschitz condition means that the feedback in the differential equation is weak. We define a class of polynomial-space computation tableaux with equally restricted feedback, and show that they are still polynomial-space complete. The same technique also settles Ko's two later questions on Volterra integral equations.Let gW OE0; 1 R ! R be a continuous function and consider the initial value problemThe Picard-Lindelöf (or Cauchy-Lipschitz) Theorem [15] states 1 that this equation has a unique solution hW OE0; 1 ! R if g is Lipschitz continuous (along its second argument), i. e., (2) jg.t; y 0 / g.t; y 1 /j Ä Z jy 0 y 1 j; t 2 OE0; 1; y 0 ; y 1 2 R for some constant Z independent of y 0 , y 1 and t . We are interested in the computational complexity of the solution h under this condition. Our model of computation of real functions is reviewed in Section 1. It is adopted from computable analysis and is thus consistent with the conventional notion of computability (see Section 5.3 for other perspectives on the "complexity" of similar problems). We formulate our main result in Section 2: the solution of the above equation can be polynomialspace complete, even if g is polynomial-time computable. This was open since 1983 [18]. The proof will be given in Section 3. The main idea is to regard the differential equation with the Lipschitz condition as a polynomial-space computation tableau with certain restrictions. In Section 4, we use the same techniques solve several other problems, including the ones about Volterra integral equations [20]. Section 5 discusses related results and problems.Key words and phrases. computable analysis; computational complexity; exponential space; initial value problem; Lipschitz condition; ordinary differential equations; Picard-Lindelöf Theorem; polynomial space; Volterra integral equations.This work was supported in part by the Nakajima Foundation and by the Natural Sciences and Engineering Research Council of Canada.1 There are several variants of the theorem; here is a proof sketch for ours. Let C be the set of all continuous real functions on OE0; 1. A solution of (1) is a fixed point of the operator T W C ! C defined byThis solution exists and is unique by the Banach fixed point theorem, because T is a contraction with respect to the distance d given by d.h 0 ; h 1 / D max t2OE0;1 exp. 2Zt /jh 0 .t/ h 1 .t/j for h 0 , h 1 2 C . To compute a real function f , the machine should output an approximation of f .t / to given precision 2 m by consulting the oracle for approximations of t to any precision 2 n it desires (left). An alternative picture (right) is that the machine converts any stream of improving approximations of t to a stream of improving approximations of f .t/.

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Extensive clinical studies of Helicobacter pylori have shown this bacterium to be an important causative factor of peptic ulcer, particularly in its recurrence. Therefore, numerous therapeutic trials for the eradication of H. pylori have been reported. A recent trend in curative therapy has been so-called triple therapy, using a proton pump inhibitor and two different antimicrobials. 1 Sucralfate, which is a widely used cytoprotective agent for the gastric mucosa, is reported to inhibit several of the activities of H. pylori and to enhance the anti-H. pylori activity of antimicrobial agents. 2±11 Therefore, several studies of sucralfate-based eradication therapy have been reported recently. 12±18 However, the ef®cacy and safety of sucralfate-based therapy are still controversial. 19±20 The present study was designed to evaluate the ef®cacy and safety of sucralfate in combination with amoxycillin and clarithromycin as eradication therapy for H. pylori, in comparison with lansoprazole-based triple therapy. PATIENTS AND METHODS PatientsThis study was designed as a prospective, randomized, multicentre study, and was carried out in accordance SUMMARY Background: Sucralfate has an inhibitory action against Helicobacter pylori and enhances the anti-H. pylori activity of antimicrobials. Aim: To evaluate the ef®cacy and safety of sucralfatebased eradication therapy for H. pylori infection, compared with that based on lansoprazole, in a randomized multicentre study. Subjects and methods: The subjects were 150 H. pyloripositive patients. They were randomly assigned to one of two regimens for 2 weeks: sucralfate 1 g t.d.s., amoxycillin 500 mg t.

The fifth cytological examination of urine showed Case report tumour cells. Abdominal CT was used to visualize the right blind-ending bifid ureter and the thickness of its A 67-year-old Japanese woman with a history of surgical and irradiation treatment for breast cancer presented walls. The diagnosis was cancer in the blind-ending branch of the bifid ureter, for which a total nephrouret-with macroscopic haematuria; IVU revealed moderate dilatation of the right ureter. Four urine specimens were erectomy was indicated (Fig. 1). During surgery, the blind-ending branch was found to be filled with serous, all negative for malignant cells, including the specimen obtained from right ureteric catheterization. The right dark brown fluid and the orifice of the lumen was narrow. The surgical specimens showed TCC, grade 3, retrograde ureterogram showed a short ascending branch originating in and lateral to the lumbar ureter. pT3N0M0 (Fig. 2), and the patient received adjuvant a b Fig. 2. a, Whole-mount section showing non-papillary, invasive tumours in the blind-ending branch (arrow). b, Histologically, the Fig. 1. Cut surface of the blind-ending ureter (opened longitudi-tumours were transitional cell carcinoma, grade 3. Haematoxylin and eosin, reduced from ×200. nally) showing irregular mucosa (arrow). 307