STUDY ON CYTOKINE PRODUCTION OF PATIENTS WITH PULMONARY TUBERCULOSIS : 2. INVESTIGATION ON PRODUCTION OF CYTOKINES BY PERIPHERAL MONONUCLEAR CELLS FROM PATIENTS WITH PULMONARY TUBERCULOSIS

Interferon-γ (IFN-γ) and interleukin-10 (IL-10)-producing ability of peripheral blood mononuclear cells (PBMC) obtained from patients with active pulmonary tuberculosis (N=17) and healthy controls (N=14) were assessed upon stimulation with purified protein derivatives (PPD). Blood was extracted on two occasions from each patient with active pulmonary tubercu- losis without any underlying diseases ; before the initiation of anti-tuberculous chemother- apy and 2 months later from the negative conversion of Mycobacterium tuberculosis in sputum culture. Adherent cells and non-adherent cells were prepared from PBMC. IFN-γ and IL-10 level were measured by ELISA in culture supernatants of adherent cells and non-adherent cells stimulated with PPD. Non-adherent cells obtained on admission produced IFN-γ significantly higher than did the cells of healthy controls (P＜0.001). Elevated production of IFN-γ by non-adherent cells obtained on admission was reduced after anti-tuberculous treatment (P＜0.03). IL-10 production by non-adherent cells of the patients was lower than that by the cells of healthy controls, although the difference was not statistically significant. IL-10 production by non-adherent cells obtained on admission was significantly correlat- ed with the duration of culture positive in the sputum (P＜0.05). IL-10 level produced by adherent cells from nutritionally normal patients was significant- ly higher than that of healthy controls(P＜0.05), and elevated IL-10 level was significantly reduced aft er therapy (P＜0.05). In the normonourished patients, the duration of culture positive in the sputum of patients with higher level of IL-10 of non-adherent cells (N=5) was significantly longer than that of patients with reduced IL-10 levels after therapy. These results suggests that IL-10 produced by monocytes may diminish the TH 1 responses of patients with pulmonary tuberculosis

Runs bAsed Traffic Estimator (RATE): A Simple, Memory Efficient Scheme for Per-Flow

Per-flow network traffic measurements are needed for effective network traffic management, network performance assessment, and detection of anomalous network events such as incipient DoS attacks. Explicit measurement of per-flow traffic statistics is difficult in backbone networks because tracking the possibly hundreds of thousands of flows needs correspondingly large high-speed memories. To reduce the measurement overhead, many previous papers have proposed the use of random sampling and this is also used in commercial routers (Cisco's NetFlow). Our goal is to develop a new scheme that has very low memory requirements and has quick convergence to within a pre-specified accuracy. We achieve this by use of a novel approach based on sampling two-runs to estimate per-flow traffic. (A flow has a two-run when two consecutive samples belong to the same flow). Sampling two-runs automatically biases the samples towards the larger flows thereby making the estimation of these sources more accurate. This biased sampling leads to significantly smaller memory requirement compared to random sampling schemes. The scheme is very simple to implement and performs extremely well