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At least 127 records · Page 7Linked to original sources
PubMed1986

Current risks and protocols for operations for double-outlet right ventricle. Derivation from an 18 year experience.

Recent follow-up of 127 patients having repair of double-outlet right ventricle during an 18 year experience (1967 to July, 1984) indicated an overall actuarial survival rate at 12 years of 38%. However, multivariate analysis supported by contingency tables indicated that currently the early (2 week) survival rate after the intraventricular tunnel repair for double-outlet right ventricle with subaortic ventricular septal defect in 6-month-old infants is 99% and the 10 year survival rate 97%. Reoperation of the tunnel repair was rarely required (one of 56 patients), and the functional results were excellent. Results were similar in patients with doubly committed ventricular septal defect, except that two of 10 patients developed typical discrete localized subaortic stenosis late postoperatively. Early and late results in patients with double-outlet right ventricle and subpulmonary ventricular septal defect were poor when an atrial switch operation was part of the repair; when an intraventricular tunnel repair between the left ventricle and aorta was combined with a right ventricular-pulmonary arterial conduit, no early deaths occurred, but three patients died late postoperatively. Several techniques of repair of double-outlet right ventricle with noncommitted ventricular septal defect have provided only a 22% overall 10 year survival rate. These data are used to derive inferences as to optimal treatment protocols.

Actuarial Analysis↗
PubMed2026

Impact of PerioperAtive LidocAine Infusions on Enhanced Recovery After Noncardiac Surgery (IMPALA-ERAS) in an inpatient setting: rationale, design and protocol for a sequential, repeated crossover trial.

INTRODUCTION: Multimodal analgesic strategies designed to minimise perioperative opioid exposure are fundamental components of enhanced recovery after surgery (ERAS) pathways. Despite widespread implementation of ERAS protocols, the optimal analgesic regimen remains undefined, as the individual contributions of specific agents to overall analgesic efficacy and opioid-sparing effects are not fully elucidated. Intravenous lidocaine, a widely utilised local anaesthetic, possesses both analgesic and anti-inflammatory properties and has been associated with improved gastrointestinal recovery. This study seeks to pragmatically evaluate the impact of incorporating perioperative intravenous lidocaine infusion into established ERAS pathways on postoperative functional recovery. METHODS AND ANALYSIS: The Impact of PerioperAtive LidocAine Infusions (IMPALA) on ERAS trial is a single-centre, pragmatic, cluster-randomised, double-blinded, placebo-controlled study. A total of 2290 patients undergoing elective colorectal surgery, emergency general surgery, urology, ventral hernia repair, surgical oncology or spine surgery will be randomly assigned to receive either intraoperative and postoperative intravenous lidocaine infusions (administered for up to 48 hours) or placebo as part of a standardised multimodal analgesic regimen integrated into established ERAS pathways. The primary outcome is case mix index-adjusted resource length of stay, defined as the time interval from surgical initiation to hospital discharge adjusted for case mix index. The primary outcome is total inpatient opioid consumption within the first 72 hours, reported in oral morphine milligram equivalents. Secondary outcomes include various in-hospital clinical endpoints derived from the electronic health record. ETHICS AND DISSEMINATION: This protocol and accompanying statistical analysis plan outline the study design, primary and secondary endpoints and analytic methodology. The IMPALA-ERAS trial has received ethical approval from the Vanderbilt University Institutional Review Board (IRB: 250617). The findings will be disseminated via peer-reviewed publications and presentations at national conferences. Results from this trial are expected to inform evidence-based practices regarding perioperative lidocaine infusion and its potential contributions to enhanced postoperative recovery in surgical patients. TRIAL REGISTRATION NUMBER: NCT07224711.

Humans↗
PubMed1981

Improved survival from acute lymphoblastic leukemia in adolescents and adults.

Nineteen adult patients with acute lymphoblastic leukemia were treated with combination chemotherapy to induce remission in the period from 1971 to 1979. Those patients achieving remission received intensive post-remission therapy with central nervous system (CNS) prophylaxis, followed by two-drug maintenance therapy, and reinduction courses of chemotherapy every six months. Remissions were achieved in 17 of the 19 patients (89%). Twelve patients (63%) are alive, 11 currently in complete remission. Two patients who experienced relapses in recent months have successfully undergone transplantation with allogeneic marrow from sex-matched, HLA-compatible sibling donors. The median survival and median duration rates of first remissions have not yet been reached, but to date are 36+ months and 29+ months, respectively with a predicted five-year survival rate of 61%. These results not only are significantly better than those achieved in the years 1968 to 1971 in our institution, but also are superior to others reported in the world medical literature. The combination of optimal treatment protocols with allogeneic marrow transplantation for patients with poor prognoses is expected to improve the survival of adult patients even further in the next decade.

Adolescent↗
PubMed1989

Immune responses to influenza virus in orally and systemically immunized mice.

In our studies on the induction of an immune response by oral immunization, we have explored the potential of a novel approach for antigen delivery by microencapsulation. This procedure preserved the immunogenicity of the influenza virus introduced by either systemic or oral routes. Furthermore, the levels of specific antibodies in serum and in saliva were enhanced and lasted longer (up to 4 months) in animals immunized with of antigens in microencapsulated form than in animals immunized with equal doses of free suspension. Preliminary challenge experiments showed a correlation between levels of antibodies and protection. All mice systemically immunized were protected against the virus, while mice orally immunized with lower doses of microencapsulated antigen had better survival rates than those immunized with higher doses. Additional experiments suggested that low doses of immunogen were able to generate better protective immunity than high doses, which may instead be tolerogenic. Further experiments with a well characterized microencapsulated antigen (size of microcapsules, time of release of antigen, as well as its dose and form) will be necessary to establish conditions for optimal immunization protocols applicable for the oral or systemic routes.

Administration, Oral↗
PubMed1989

Mechanism of immunotherapeutic activity of OK-432 in the treatment of peritoneal carcinomatosis.

In this report the mechanism of therapeutic activity of OK-432 for the treatment of peritoneal carcinomatosis was investigated by correlating effector-cell augmentation with therapeutic activity in rats bearing MADB-106 carcinomatosis. Tumor cells were injected i.p. and the treatment with OK-432 was initiated 5 days later with 0.5, 1, 5 or 10 KE/animal of OK-432 injected i.p. semiweekly. Significant therapeutic activity was observed at all doses examined with greater prolongation of survival noted at the higher doses of OK-432. Animals treated with 0.5 KE/animal had a prolongation of the median survival time from 14 days for saline-treated animals to 17 days for the OK-432 treated animals (P less than 0.0008), while animals treated with higher doses had much longer periods of survival, some animals being tumor-free at 185 days. In the same studies, natural killer (NK) cell, lymphokine-activated killer cell, cytotoxic T lymphocyte, and macrophage tumoricidal/cytostatic activities were measured 7 days and 14 days following tumor injection (2 days and 9 days after initiation of immunotherapy). OK-432 had immunostimulatory activity in most of the assays of immune function examined and this correlated with host survival, including augmentation of peritoneal and peripheral blood cytotoxic T lymphocyte activity on day 14, peritoneal and alveolar macrophage activity on day 7 and day 14, as well as natural killer cell activity on day 14. These results suggest that the therapeutic doses are also immunomodulatory doses for the effector cells mentioned above. We suggest, therefore, that immunological monitoring may help to optimize treatment protocols for the treatment of peritoneal and perhaps pleural effusions with OK-432.

Adjuvants, Immunologic↗
PubMed1987

Nerve growth factor-like immunoreactivities in rodent salivary glands and testis.

A series of polyclonal affinity-purified antibodies against mouse submandibular-gland nerve growth factor (NGF) are described. Using the submandibular gland of the male mouse and indirect immunofluorescence, the specificity and sensitivity of affinity-purified immunoglobulins and various other fractions from the immunized animals have been tested. It will be shown that affinity-purification schemes, including pre-purification of protein A-fractionated immunoglobulins to remove antibodies that bind to unrelated hydrophilic and hydrophobic proteins, significantly enhance the signal-to-noise ratio and specificity of the antibodies. The antibodies effectively detect NGF-like immunoreactivity in both fresh and fixed glandular tissue. Optimal fixation procedures are described. Fluorescence intensities are linearly correlated to log antibody concentration. By use of the best antibody fractions and optimal fixation protocols, the distribution of NGF-like immunoreactivity is described in eight different salivary glands (rat and mouse, male and female, submandibular and sublingual glands). In addition to the well-known large numbers of immunoreactive cells in the submandibular gland of the male mouse, immunoreactive cells were found in the sublingual gland of male mice and in the submandibular and sublingual glands of female mice. One antibody revealed a weak specific fluorescence also in the submandibular gland of the male mouse. In a survey of genital organs of male mice, one antibody revealed fluorescence in the germ cell line. We conclude that several polyclonal affinity-purified antibodies have been characterized that show a strong NGF-dependent binding to the secretory granules of tubular cells in the submandibular gland of male mice. These antibodies should make it possible to locate endogenous and perturbed NGF levels immunocytochemically, e.g., in the peripheral and central nervous system, where NGF concentrations may be several orders of magnitude lower than in the salivary glands.

Animals↗
PubMed1991

Bayesian estimation of doxorubicin pharmacokinetic parameters.

Doxorubicin was given by brief i.v. infusion (doses ranging from 25 to 72 mg/m2) to 28 patients for 2-7 successive courses of chemotherapy (68 courses studied in all). A Bayesian approach was developed to determine the individual pharmacokinetic parameters of doxorubicin. Statistical characteristics of the population pharmacokinetic parameters were first evaluated for 19 patients and a total of 30 courses, which, when combined with 4 individual plasma concentrations of drug, led to a Bayesian estimation of individual pharmacokinetic parameters for the remaining 38 courses. The estimated parameters for the elimination phase (A3/V1 and t1/2 elimination) and the residual plasma level at 48 h as computed by Bayesian estimation on this reduced sub-optimal sampling protocol were compared with a maximal likelihood estimation of these parameters. No statistically significant differences were found. Performance of the developed methodology was evaluated by computing bias and precision. The mean errors were -0.0315 x 10(-4) l-1 for A3/V1, 0.0839 h for t1/2 elimination, and -0.22 ng/ml for c(48 h). The precision of the prediction of these three parameters (0.304 x 10(-5) l-1, 3.34 h, and 0.659 ng/ml, respectively) remained lower than the interindividual standard deviation (1.42 x 10(-4) l-1, 14.9 h, and 4.54 ng/ml, respectively). This procedure enables the estimation of individual pharmacokinetic parameters for doxorubicin at minimal cost and minimal disturbance of the patient.

Bayes Theorem↗
PubMed1991

Biological assays for irritant, tumor-initiating and -promoting activities. III. Computer-assisted management and validation of biodata generated by standardized initiation/promotion protocols in skin of mice.

The initiation/promotion standard protocol 28 (protocol 28), developed and used previously as an experimental model to verify the cancerogenic process of initiation/promotion in mouse skin, was revised in three aspects: (a) statistically it was shown sufficient to use, per promoter dose group, 16 colony-outbred female NMRI mice: (b) by weekly individual records of tumor response (and health status) of each mouse in a dose group, cumulative tumor incidences (and mean and extreme body weights) are determined; from these data the collective records (tumor response, health status), the only data accessible from protocol 28, may be generated in addition; (c) the details of dose groups and all data on tumor response and health status are processed by computer using the program package PAPILLOM. The latter was developed specifically for this purpose, is written in the programming language APL and designed for easy handling by staff of animal laboratories. The program package calculates, from the individual records per promoter dose group, cumulative tumor incidences (and survival data) with confidence limits for any one exposure time, and the package may be linked to programs for statistical validations. In addition, from the collective records it calculates the tumor rates, tumor yields and survival rates for any one exposure time. These data, obtained by either of the standard protocols (16 or 28), are fully comparable. For pure compounds they may be used to calculate semiquantitative tumor-promoting potencies. These values for more than 80 polyfunctional diterpenes of the tigliane, ingenane and daphnane type, scattered in or calculated from previous papers, together with their irritancies, were compiled. Within recent years, computer-assisted standard protocol 16 has been used to handle and evaluate about 1000 promoter dose groups. Protocol 16 allows one to extract and utilize more and better toxicological information on tumor response and health status from any one dose group, utilizing significantly fewer experimental animals than required by protocol 28. Thus, the computer-assisted standard protocol 16 optimizes the utility of the experimental model of mouse skin for the amount, quality and management of experimental data as well as for the requirements of animal protection.

Animals↗
PubMedDate not supplied

An investigation of heparinase immobilization.

A systematic investigation of the parameters that affect the efficiency of immobilizing heparinase onto cyanogen bromide activated crosslinked 8% agarose beads was conducted. Two experimental measures, the "fraction bound" and the "fraction retained," were used to monitor the coupling efficiency. The fraction bound is the portion of the total initial enzyme that is bound to the agarose gel. The fraction retained is the fraction of bound enzyme that is active. The product of the two measures indicates the coupling efficiency. The activity of the immobilized heparinase was measured under conditions free of both internal and external mass transfer limitations, and thus, the fraction retained represents the true immobilized enzyme activity. Increasing the degree of activation of the beads results in an increase in the fraction bound, the fraction retained, and consequently, the coupling efficiency. As the ratio of enzyme solution to gel volume increases from 1.5 to 2.2, the fraction bound remains constant but the fraction retained decreases (heparinase concentration; 0.15 mg/mL and degree of activation; 9.5 mumol of cyanate esters/g of gel). At volume ratios greater than 2.2, both the fraction bound and the fraction retained decline continuously. Changing the heparinase concentration in the coupling solution changes the coupling efficiency in a manner similar to that of the volume ratio change. When heparin is added during the coupling process, the fraction bound declines as the heparin concentration increases, whereas the fraction retained increases up to a heparin concentration of 12 mg/mL and decreases thereafter. When arginine, lysine, and glycine are used to block the unreacted cyanate ester groups after the coupling process, the immobilized heparinase shows different pH optima of 6.5, 6.9, and 7.2, respectively. Based upon these findings, a protocol to optimize heparinase immobilization is developed.

Cross-Linking Reagents↗
PubMed1988

(Neo)glycoproteins as tools in neuropathology: histochemical patterns of the extent of expression of endogenous carbohydrate-binding receptors, like lectins, in meningiomas.

Biotinylated (neo)glycoproteins were used to specifically detect endogenous sugar receptors such as lectins in sections of formaldehydefixed, paraffin-embedded tissue from meningiomas. The histochemical methods used consisted of the application of a carrier protein and various covalently linked sugar moieties, available mainly through chemical synthesis, in an optimized standard protocol. They proved valuable in elucidating differential binding patterns within the various meningioma subtypes. alpha-Fucoside-, beta-galactoside-, alpha-mannoside- and beta-xyloside-specific carbohydrate-binding receptors were detected in all the tumor subclasses examined, although the levels of expression exhibited pronounced quantitative differences. In addition, differences in the extent of histochemical staining were observed, using a labelled carrier protein, derived from N-acetylglucosamine and mannose-6-phosphate moieties, respectively. Quantitative differences in the reaction intensity were also measured in the respective subtypes. Receptors for N-acetyl-D-galactosamine were detected only in the analplastic forms, while glucuronic acid-specific receptors were only present in the meningotheliomatous meningioma. In contrast to the other types, malignant meningiomas failed to show cytoplasmic staining with the alpha-glucoside-specific maltose-(BSA-biotin). Distinct differences in the pattern of expression of endogenous sugar receptors, evaluated by a standard protocol, provided further evidence for a possible additional subtype of meningioma, the submalignant meningioma. Our results suggest that labelled (neo)glycoproteins could be used routinely as tools for assessing the expression of endogenous sugar receptors in diagnostic neuro-oncology.

Biomarkers, Tumor↗
PubMed1988

Intravenous fenoldopam in heart failure: comparing the hemodynamic effects of dopamine1 receptor agonism with nitroprusside.

Dopamine1 receptors mediate hemodynamic effects that may be beneficial in patients with congestive heart failure. We infused the selective dopamine1 receptor agonist, fenoldopam mesylate (SKF 82526 J), to evaluate hemodynamic and neurohumoral changes during continuous intravenous infusion in patients with congestive heart failure and compared them with the effects of nitroprusside, a traditional vasodilator that works by a distinctly different mechanism. In 15 patients with a mean radionuclide ejection fraction of 17%, the agents were infused in a random-ordered, double-blinded, crossover, active drug-controlled protocol after optimal dosing was determined during a titration period. Hemodynamic changes were induced in minutes with both drugs during a mean (+/- standard deviation) infusion dose of 1.45 +/- 1.66 micrograms/kg/min for fenoldopam and 2.99 +/- 1.59 micrograms/kg/min for nitroprusside. At 1 hour, mean blood pressure decreased and cardiac index rose with both drugs, and the effect lasted throughout the 6-hour infusion period. Nitroprusside, but not fenoldopam, reduced right heart filling pressures (including mean pulmonary capillary wedge, mean right atrial, and mean pulmonary artery pressures) during the infusion period. Both drugs caused significant reduction in systemic vascular and pulmonary arteriolar resistances. No significant change occurred in plasma norepinephrine levels. Fenoldopam ameliorates some of the adverse hemodynamic changes that occur during heart failure but does not reduce right heart filling pressures as does nitroprusside. Because of fenoldopam's unique characteristics, it may benefit certain patients with heart failure.

Adult↗
PubMed1978

Gestational trophoblastic neoplasms: morphologic correlates of therapeutic response.

GTN were evaluated histologically in reference to biologic behavior and response to chemotherapy. GTN requiring more intensive, multiple drug chemotherapy usually exhibited increased mitotic activity, nuclear atypias, compact growth of cytotrophoblast, and little maturation, as compared to lesions that responded more favorably. Fibrinoid at the interface of tumor and host tissues was associated with a favorable response to drug therapy. Patients requiring more intensive chemotherapy were more likely to present with distant metastases and high levels of hCG prior to treatment and to reach remission only after many courses of treatment. The clinical and morphologic features of fatal cases suggest that these represented the extreme of a biologic continuum, with collapse of defense mechanisms despite chemotherapy. The early recognition by the pathologist of those lesions that may be resistant to chemotherapy is important to the clinician in selection of an optimal treatment protocol.

Adolescent↗
PubMed1982

Species differences in circulating prostaglandin metabolites. Relevance for the assay of prostaglandin release.

The profiles of circulating metabolites of prostaglandin F2 alpha were investigated in a number of species, viz. rat, rabbit, guinea pig, cattle and sheep. The aim of the study was to identify in each animal major plasma metabolites that outlast the initially formed, short-lived 15-keto-13, 14-dihydroprostaglandin F2 alpha and might thus serve as better parameters for monitoring prostaglandin production in vivo. Tritium-labeled prostaglandin F2 alpha was injected intravenously and frequent blood samples were collected. The metabolic profiles at different stages were visualized using two-dimensional thin-layer chromatography and autoradiography. Identification of circulating products was achieved by comparison with reference compounds using several chromatographic methods, and by gas chromatography-mass spectrometry in cases where larger amounts of the prostaglandin had been administered. In the rabbit a similar study was also done with tritium-labeled prostaglandin E2. Certain species differences were seen in the removal of labeled compounds from the circulation, the elimination being most efficient in the guinea pig. Further differences were seen in the profiles of circulating prostaglandin metabolites. The first appearing major prostaglandin F2 alpha metabolite was always 15-ketodihydroprostaglandin F2 alpha. However, this compound was later replaced in the circulation by a number of more degraded products, the profiles of which were relatively typical for each species. Thus, in cattle, rat and guinea pig, the earliest-formed metabolites, 15-ketodihydroprostaglandin F2 alpha and its tetranor counterpart, 5 alpha, 7 alpha-dihydroxy-11-ketotetranorprostanoic acid, remained comparatively prominent plasma products, whereas highly polar dicarboxylic acids rapidly dominated the metabolite spectrum in the ovine and lapine circulation. These differences were further supported by separate kinetic experiments, using unlabeled prostaglandin F2 alpha and radioimmunological determination of formed products. These latter experiments also demonstrated further pronounced species differences in the rat of elimination of the different prostaglandin metabolites. A considerable interconversion between prostaglandin E and F compounds was also demonstrated in some species. In conclusion, the traditional prostaglandin parameters in plasma, the 15-ketodihydrometabolites, were found not to be the best parameters in all species. It is suggested that species differences in prostaglandin metabolism are taken ito consideration when the optimal analytical protocol is sought for future biological studies. Some alternatives are suggested in the present paper.

Animals↗
PubMed1990

The use of E. coli exonuclease III to generate single stranded DNA in BrdUrd cell-cycle analysis permits simultaneous detection of cell surface antigens.

An immunocytochemical method for the simultaneous flow cytometric quantitation of total cellular DNA, incorporated 5-bromo-2'-deoxyuridine (BrdUrd) and one or more cell surface antigens has been developed. Biotin labeling of cell surface antigens, critically tuned fixation techniques and an enzymatic denaturation of cellular DNA are the essential features of this method. Enzymatic denaturation of cellular DNA was shown to prevent loss of cell surface antigen-bound biotin moieties, and thus to preserve cell surface immunofluorescence distribution. After a mild protein extraction and the introduction of breaks into the chromatin using restriction endonucleases, E. coli exonuclease III was used to generate stretches of single stranded DNA. This approach permits detection of the incorporated BrdUrd using anti-BrdUrd monoclonal antibodies. The enzymatic denaturation protocol was optimized using in vitro BrdUrd-labeled L1210 murine leukemia cells, and applied to both in vivo and ex vivo BrdUrd-labeled murine bone marrow cells. With this new method it is possible to study DNA content, cell cycle kinetics and cell surface antigen expression simultaneously, and hence functional relationships between these parameters can be investigated.

Animals↗
PubMed1987

Radioimmunoassay of epitestosterone: methodology, thermodynamic aspects and applications.

A radioimmunoassay system for 17 alpha-hydroxy-4-androstene-3-one (epitestosterone) was developed and evaluated using rabbit antisera against 17 alpha-hydroxy-4-androstene-3-one-3-(O-carboxymethyl)-oxime-bovine serum albumin conjugate, and radioiodinated homologous histaminyl derivative of epitestosterone as a tracer. Two antisera with different specificity were used for radioimmunological determination of epitestosterone in hydrolyzed urine and plasma, respectively. Apparent intrinsic association constants and derived thermodynamic variables for ligand-antibody interaction were measured under various conditions in order to set up an optimal assay protocol. The mean plasma epitestosterone levels for healthy subjects were 0.44 +/- 0.15 nmol.l-1 (means +/- SD) in males and 0.092 +/- 0.056 nmol.l-1 in females. The corresponding concentrations in urine were 320 +/- 70 nmol.l-1 (males) and 273 +/- 100 nmol.l-1 (females).

Body Fluids↗
PubMed1990

Aggressive chemosurgical debulking in patients with advanced ovarian cancer.

From July 1986 to June 1989, 43 evaluable patients with advanced ovarian cancer were treated on protocol with initial cytoreductive surgery, two courses of high-intensity intravenous Cytoxan (1000 mg/m2) and cisplatin (120-200 mg/m2) chemotherapy, and repeat debulking laparotomy in an effort to maximize response to a subsequent four cycles of intraperitoneal platinum-based chemotherapy. Two patients were stage IIIA, 2 stage IIIB, 28 stage IIIC, and 11 stage IV. Five tumors were grade 1, 9 grade 2, and 29 grade 3. Thirty-eight (88%) patients had bulky tumor (5-25 cm) found at first laparotomy; 25 of these had greater than 1-cm residual after initial debulking. Following two cycles of intensive intravenous chemotherapy 18 of these 25 had greater than 1-cm disease found at second laparotomy; 12 of 18 underwent secondary cytoreduction to less than 1 cm. Thus, 30 of these 38 (79%) patients entered the intraperitoneal phase of the protocol with less than 1-cm disease. Four patients had 2- to 5-cm tumor at initial laparotomy; two of four were debulked to less than 1-cm residual. All four were found to have less than 1-cm disease at second laparotomy. This combination regimen was well tolerated. There was one treatment-related death. In sum, 42 of 43 patients had tumor greater than 2 cm at staging laparotomy and 38 (88%) had large, bulky disease (5-25 cm); 34 of 43 (79%) entered the intraperitoneal phase of the protocol with optimal (less than 1-cm) disease. Aggressive chemosurgical cytoreduction in patients with bulky advanced ovarian cancer can leave a large proportion of patients with minimal residual disease and maximize their chances of responding to subsequent intraperitoneal chemotherapy.

Cisplatin↗
PubMed1990

Preparation of diethylaminoethyl hollow fibres for high-flow liquid chromatography.

A novel anion-exchange column for fast-flow liquid chromatography was developed. The column was prepared by immobilizing diethylaminoethyl groups on to the inner walls of regenerated cellulose hollow fibres. A detailed investigation was conducted of the parameters affecting diethylaminoethyl immobilization such as the NaOH concentration, the reaction temperature, the diethylaminoethyl concentration and the reaction span. Based upon the findings, a protocol to optimize the preparation of the diethylaminoethyl hollow fibres was established. The diethylaminoethyl hollow fibres prepared adsorbed 186 +/- 30 mg of albumin/g fibres.

Adsorption↗
PubMed1991

Factors affecting the specific activity of immobilized antibodies and their biologically active fragments.

Factors affecting the specific activity of immobilized antibodies and their biologically active fragments were studied with goat anti-mouse and goat anti-human immunoglobulin G. Antibodies were immobilized on HW 65 polymeric support matrix activated with carbonyldiimidazole, hydrazide and iodoacetic acid. The most significant factors influencing the specific activity of stochastic coupling of antibodies are multi-site attachment, multiple orientations and steric hindrance imposed by crowding of antibody and the size of the antigen. In oriented immobilization the specific activity is affected only by steric hindrance. The specific activity of immunosorbents prepared by immobilization of F(ab') fragments can be improved to almost 100% by limiting the amount of protein immobilization and the size of the antigen. The present study shows the protocols for optimizing immobilized antibody performance.

Adipates↗