Sustainability responsibility

Intuition dictates that reducing nutrient inputs, particularly phosphorus, must reduce the supportable biomass. Relationships show that sustained response cannot be effected before it can be demonstrated (i) that nutrient is exhausted at a lower concentration of algae than the existing maxima and (ii) that in situ recycling is unable to make up the shortfall. 

A potential pitfall with stop-time experiments comes with temporal instability of responses. When a steady-state sustained response is observed with time, then a linear portion of the production of reporter can be found (see Figure 5.15b). However, if there is desensitization or any other process that makes the temporal responsiveness of the system change the area under the curve will not assume the linear character seen with sustained equilibrium reactions. For example, Figure 5.16 shows a case where the production of cyclic AMP with time is transient. Under these circumstances, the area under the curve does not assume linearity. Moreover, if the desensitization is linked to the strength of signal (i.e., becomes more prominent at higher stimulations) the dose-response relationship may be lost. Figure 5.16 shows a stop-time reaction dose-response curve to a temporally stable system and a temporally unstable system where the desensitization is linked to the... 

Similar to HBV, infections with hepatitis C virus (HCV) have a high rate of progression from an acute to a chronic state that frequently leads to cirrhosis or hepatocellular carcinoma [2]. Monotherapy for HCV infection with IFN-a or combined therapy with ribavirin and IFN-a is associated with initial rates of response as high as 40%. The rates of sustained responses are, however, lower and also depend on the viral genotype. In patients infected with HCV genotype 2 or 3, the response was maximal after 24 weeks of treatment, whereas patients infected with genotype 1 -the most frequent in the USA and Europe - required a minimum treatment course of 48 weeks for an optimal outcome. 

Sorger, P.K. (1990). Yeast heat shock factor contains separable transient and sustained response transcriptional activators. Cell 62,793-805. 

Interim results from the SPRINT-1 phase 2 trial of boceprevir (SCH 503034) have been released. In subjects who received boceprevir plus interferon-a and ribavirin, viral RNA loads were suppressed at week 12 in between 70 and 79% of subjects infected with genotype 1 HCV, compared with only 34% in the interferon-o/ ribavirin standard of care arm (www.sch-plough.com/schering plough/news/release. jsp releaseID = 1064540). However, it is not yet known if this enhanced early response will translate into sustained response. 

Lok and McMahon 2007), but the ideal outcome is undetectable HBV DNA (< 10-30lU/ml) in highly sensitive real-time PCR-based assays. In HBeAg-positive patients, loss of HBeAg followed by the emergence of anti-HBe antibodies ( e seroconversion) indicates a sustained response to therapy when it persists after treatment cessation. HBs seroconversion (loss of HBsAg and emergence of anti-HBs antibodies) is the most desirable endpoint, as it indicates a complete response with sustained remission from HBV disease. It is rarely achieved with cnrrent therapies. 

Compared to those treated with placebo, 60% to 70% of patients with HBeAg-negative hepatitis B treated with lamivudine for 52 weeks have undetectable HBV DNA levels and normalization of ALT levels. However, the rate of relapse is 80% to 90% once the treatment has been discontinued.20 Lamivudine therapy beyond 12 months may be considered to sustain response, but biochemical and virologic breakthrough commonly occurs due to the development of drug resistance.29... 

Subcutaneous (SC) administration of ESA produces a more predictable and sustained response than IV administration, and is therefore the preferred route of administration for both agents. Intravenous administration is often utilized in patients who have established IV access or are receiving hemodialysis. Starting doses of ESAs depend on the patient s Hgb level, the target Hgb level, the rate of Hgb increase and clinical circumstances.31 The initial increase in Hgb should be 1-2 g/dL (0.6206-1.2404 mmol/L) per month. The starting doses of epoetin alfa previously recommended are 80 to 120 units/kg per week for SC administration and 120 to 180 units/kg per week for IV administration, divided two to three times per week. The starting dose of darbepoetin alfa is 0.45 mcg/kg administered SC or IV once weekly (Table 23-3). 

Yee LJ, Tang J, Gibson AW, Kimberly R, Van Leeuwen DJ, Kaslow RA. Interleukin 10 polymorphisms as predictors of sustained response in antiviral therapy for chronic hepatitis C infection. Hepatology 2001 33[3] 708—712. 

In order to maintain sustained responsiveness to repetitive firing and the structural integrity of the synapse,... 

Kotlikoff Returning to the issue of receptor-operated or store-operated channels, one of the things I noticed in your traces was that your caffeine responses came back to baseline very smoothly. There was not the sustained elevation of [Ca2+] that you might predict. One of the things that is very different about voltage-clamped smooth muscle between a caffeine response and a phospholipase receptor-linked response is this additional current that is seen with the phospholipase receptor. I didn t see any functional evidence of a sustained response in your caffeine experiments. Have you voltage clamped these cells and looked to see whether there is any current there If not, do you think this is because the current is just too small to be able to measure ... 

Peginterferon alfa-2a treatment results in more sustained responses than simple interferon alpha, although relapse is not uncommon. Such treatment should generally be avoided in those receiving immunosuppressants and those with decompensated liver disease. Lamivudine, a reverse transscriptase inhibitor is often used in initial treatment and in decompensated liver disease. 

A slow intravenous injection of histamine produces marked vasodilation of the arterioles, capillaries, and venules. This causes a fall in blood pressure whose magnitude depends on the concentration of histamine injected, the degree of baroreceptor reflex compensation, and the extent of histamine-induced release of adrenal catecholamines. Vasodilation of cutaneous blood vessels reddens the skin of the face, while a throbbing headache can result from vasodilation of brain arterioles. Vasodilation is mediated through both Hj- and Hj-receptors on vascular smooth muscle. Stimulation of Hj-receptors produces a rapid and short-lived response, whereas stimulation of H2-receptors produces a more sustained response that is slower in onset. Stimulation of Hj-receptors on sympathetic nerve terminals inhibits the release of norepinephrine and its associated vasoconstriction. 

Response rates (normal ALT, HCV RNAnegative) of 9-mcg dose approximately 35% about half those have sustained response 24 wk after treatment... 

In summarizing the results, there appears to be no clear advantage to an antipsychotic-BZD combination in most patients. There was a consistent, although small, group of individuals, however, who demonstrated a rapid, dramatic, and sustained response (e.g., those who were catatonic) when treated with this combination. 

The authors have encountered some patients refractory to all other therapies who had a dramatic, full, rapid, and sustained response to methylphenidate. One study found methylphenidate effective in treating mildly depressed outpatients, particularly those who drank three or more cups of coffee a day ( 191). A replication study did not find a drug-placebo difference on the physician s ratings, but did demonstrate one for the patients subjective assessment of improvement ( 192). Another blind study of methylphenidate found improvement in an outpatient group (193). Finally, two of three trials of methylphenidate in apathetic, senile geriatric patients showed that this drug produced more improvement than placebo (194). To date, no evidence indicates that it is beneficial in cases of moderate-to-severe depression. 

The integrated cellular response of the adrenal glomerulosa cell is determined by the activities of three different protein kinases cAMP-dependent protein kinase, CaM-dependent protein kinases, and C-kinase. A sustained response can be produced by the combined activation either of the cAMP- and CaM-dependent kinases, or of the CaM-dependent kinases and C-kinase. Activation of each type of... 

Fig. 2. Messengers mediating the initial and sustained phases of the All-induced cellular response. Initial phase All-elicited hydrolysis of PIP2 induces a transient rise in cytosolic calcium (via IP3), a transient activation of calcium-, calmodulin-dependent protein kinases, a transient increase in the phosphorylation of early-phase phosphoproteins (Pra-P), and a transient cellular response. Sustained response All-elicited hydrolysis of phosphoinositides generates a sustained increase in the diacylglycerol (DG) content of the plasma membrane. In conjunction with a sustained increase in plasma membrane calcium cycling, DG induces the sustained activation of protein kinase C (CK), the sustained increase in the phosphorylation of late-phase phosphoproteins (P -P) and the sustained cellular response.

IMPDH) is an enzyme involved in guanosine nucleotide synthesis required for organisms to divide and replicate. Although tiazofurin, ribavirin, and mizoribine inhibit IMPDH, they exhibit broad cellular toxicity, lack of IMPDH enzyme specificity, and sustained response in monotherapy. Immunosuppressive agents with high IMPDH enzyme specificity have been prepared to address these concerns. 

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