Specific Factors

Studies by many workers have revealed two peptide sequences which are very selective for thrombin -Phe-Val-Arg- and -X-Pro-Arg- (C5, S24, S26). As can be seen in Table 3, these two sequences have been widely used to design the various synthetic substrates to detect thrombin. This measurement can be done directly by incubating this enzyme with the appropriate substrate. Latallo has recommended adding an agent like aprotinin or soybean trypsin inhibitor to prevent attack by kallikrein, Factor Xa, or plasmin on these thrombin substrates (L5). The use of the original substrate, S-2160, has sharply declined due to its lower sensitivity, specificity, and solubility when compared to substrates like S-2238 and Chromozyn TH. Today, 

A direct assay cannot be used to measure the level of prothrombin in plasma. This zymogen must first be converted to thrombin and then the 

Based on the work of Magnusson and co-workers with bovine prothrombin, the sequence of -Ile-Glu-Gly-Arg- has been identified as being selective for Factor Xa (M2). The commercial substrates intended to detect this enzyme therefore contain the sequence or a close derivative (A6, A7, MI). Two areas of concern in attempting to measure Factor Xa activity in biological samples are the interference from any generated thrombin and the inhibition by antithrombin III and heparin. Because of the low concentration of Factor X in plasma, only 1/10 that of prothrombin (F6, L5), the test sample can only be diluted 40- to 50-fold and one must be more concerned over fibrin formation. Van Wijk and co-workers have recommended the use of the 

As with the case of prothrombin, Factor X can be activated by both physiological and nonphysiological activators. For substrate assays, both types of activators have been employed. An example of the former is the use of thromboplastin (A6, V5) an example of the latter is the employment of Russell s viper venom (RW) in the presence of calcium ions (Al, B7, V4). In general, the latter activator appears to be favored because it does not require phospholipids for activation hence thrombin generation is retarded (A6, Dl), and decarboxylated Factor X is not activated by RW. The most frequently used substrate has been S-2222, but S-2337, which has a lower K, may become more widely used (A8, 816). 

Factor VII is the only coagulation foctor in the circulating blood which has enzymatic activity in its native form (03). While Factor VII has esterase activity, it must interact with tissue thromboplastin to form a potent activator of Factor IX or Factor X (05). An assay which could detect the presence of Factor Vila in the circulation could help to screen for those patients at a high risk for cardiovascular disease. 

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Table 4. Products Available for Treatment of Specific Factor Deficiencies...

Bench- or pilot-scale studies are necessary to demonstrate the ability of a technology to effectively treat a specific waste. Waste characteristics vary from site to site and because of this, the effect of a treatment technology with that particular waste may not be known, given the site-specific factors and conditions. Also, the proposed treatment technology may be new or unproven. 

Before the selection of a specific treatment technology can be made, an understanding of the site-specific factors which drive the selection of that technology is required because these factors can influence the evaluation of the advantages and limitations of competing technologies. The information required to resolve these site-specific issues falls into four categories waste composition and matrices, waste quantity, treatment objectives, and the reactions involved in the treatment of the contaminated material. 

The PRA procedures guide, NUREG/ CR-23(X), partitions human reliability analysis (HRA) into four phases (Figure 4.5-1). The familiarization phase, evaluates a sequence of events to identify human actions that directly affect critical process components. From plant visits and review, this part of HRA identifies plant-specific factors that affect human performance such as good or bad procedures used in the. sequence under consideration. The familiarization phase notes items overlooked during systems evaluation. 

Choosing the best implementation strategy for your company depends on a number of factors, most of which you have already identified. As you consider the benehts of each implementation strategy described in this section, it s useful to keep in mind some specific factors, including ... 

HFAM has 20 groups of factors instead of the 10 general failure types of the TRIPOD approach. The reason for this is that all of the 10 TRIPOD GFTs would be applied in all situations, even though the actual questions that make up the factors may vary. In the case of HFAM, it would be rare to apply all of the factors unless an entire plant was being evaluated. HFAM uses a screening process to first identify the major areas vulnerable to human error. The generic factors and appropriate job specific factors are then applied to these areas. For example, control room questions would not be applied to maintenance jobs. 

MANAGEMENT-LEVEL FACTORS OPERATIONAL-LEVEL GENERIC FACTORS OPERATIONAL-LEVEL JOB-SPECIFIC FACTORS... 

There are conflicting generalizations in the heterocyclic literature as to the relative reactivity of a- and y-positions in azines toward nucleophiles. Variations in the relative reactivity are attributed in this and subsequent sections to specific factors operating in addition to activation by azine-nitrogen. Another possible source of variation may be a decrease in selectivity with increasing reactivity of one or both reagents, an effect established in electrophilic aromatic... 

The reactivity of 2- and 4-halopyridines toward a variety of nucleophiles is far greater than that of the 3-halo isomers (274), which are nevertheless appreciably activated. The 4-position (cf. 271) is more reactive than the 2-position (cf. 272), except when the specific factors described in Sections II, B and III, A and also below, produce an increase in the reactivity at the 2-position. Pyridine derivatives are the least reactive of the monocyclic azines (cf. Scheme I, p. 266). 

Most infrared monitoring systems or instruments provide special filters that can be used to avoid the negative effects of atmospheric attenuation of infrared data. However the plant user must recognize the specific factors that will affect the accuracy of the infrared data and apply the correct filters or other signal conditioning required negating that specific attenuating factor or factors. 

Transcriptional regulation encompasses the modulation of the synthesis rate of mRNA due to cell type specific factors that may be triggered by external stimuli. 

Through the patient s history and physical examination, the physicians will identify any specific factor such as medications, prior procedures and medical conditions that can affect... 

A number of site-specific factors must first be evaluated. Including (1) the chemical characteristics and amount of hazardous waste, (2) the potential for release to the environment, (3) the sensitivity of the particular environment to the hazardous waste, (4) the proximity of the hazardous waste to humans, and (5) Its potential effect on human health. Then the environmental engineer must decide If a field Investigation of the site Is necessary, whether a feasibility study for remedial action Is required, what remedial action Is required to mitigate. If not eliminate, the contamination, and finally, what monitoring plan will enable the efficacy of the remedial action to be evaluated. 

Develop a comprehensive therapeutic patient monitoring plan for a patient with diabetes based on patient-specific factors. 

In patients with excess thyroid hormone production, reduce hormone production with an antithyroid drug and/or radioactive iodine. Choose therapy based on patient-specific factors and preference. 

If surgical intervention does not achieve satisfactory disease control, select subsequent appropriate pharmacologic therapy based on patient-specific factors. In selecting therapy, be sure to consider if the patient has any contraindications or allergies to therapies. 

Based on the information presented, create a care plan for BW s hot flashes and vaginal dryness. The plan should include (1) a statement identifying the patient problem and its severity, (2) goals of therapy, (3) a therapeutic plan based on individual patient-specific factors, (4) subjective and objective monitoring parameters, and (5) a follow-up evaluation to assess for adverse effects and adherence and to determine if the goals of therapy have been achieved. 

Formulate a therapeutic plan, taking into consideration patient-specific factors. 

V Mucosal tract bleeding Prolonged PT and aPTT Normal thrombin time Specific factor V assay... 

VII Mucosal tract, joint and normal aPTT Prolonged PT Specific factor VII assay... 

XIII Umbilical cord, intracranial, and joint bleeding recurrent miscarriages, impaired wound healing Normal PT, aPTT, thrombin time, bleeding time Specific factor XIII assay... 

Empirical therapy should be based on patient- and antimicrobial-specific factors such as the anatomic location of the infection, the likely pathogens associated with the presentation, the potential for adverse effects, and the antimicrobial spectrum of activity. 

Most initial antimicrobial therapy is empirical because cultures usually have not had sufficient time to identify a pathogen. Empirical therapy should be based on patient- and antimicrobial-specific factors such as the anatomic location of the infection, the likely pathogens associated with the presentation, the potential for adverse effects in a given patient, and the antimicrobial spectrum of activity. Prompt initiation of appropriate therapy is paramount in hospitalized patients who are critically ill. Patients who receive initial antimicrobial therapy that provides coverage against the causative pathogen survive at twice the rate of patients who do not receive adequate therapy initially.8... 

Figure 66-4 provides an overview of patient- and antimicrobial agent-specific factors to consider when selecting an antimicrobial regimen. It further delineates monitoring of therapy and actions to take depending on the patients response to therapy. The duration of therapy depends on patient response and type of infection being treated. 

Patient-specific factors that will affect therapy... 

The clinical presentation of osteomyelitis may vary depending on route and duration of infection, as well as patient-specific factors such as infection site, age, and comorbidities. In hematogenous osteomyelitis, the patient typically experiences systemic and localized signs and symptoms.3 4 7 12 13 In comparison, patients with chronic infection typically present with only localized signs and symptoms.4 6 A cardinal sign of chronic osteomyelitis is the formation of sinus tracts with purulent drainage.2,3,6... 

Describe the treatment options for colon cancer based on patient-specific factors, such as stage of disease, age of patient, and previous treatment received. 

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