Experimental designs for optimizing the purification of immunoglobulin G by mixed-mode chromatography.

The main aim of this study was to define the optimal adsorption and elution conditions for the purification of human immunoglobulin G (IgG) by mixed-mode chromatography using the multimodal resin Capto MMC. To this end, Central Composite Experimental Design (ED) was performed for both the adsorption and desorption stages. In the first case, the conditions were systematically studied in batch mode while in the latter case, these were performed in column. For both studies, the experimental design was conducted using high-purity human IgG samples. Buffer pH and concentration as well as the salt concentration were the parameters under study in the ED. Adsorption kinetics and equilibrium experiments were performed under the best conditions defined in the ED (phosphate buffer 60 mmol/L, pH 6.75, no salt). The equilibrium experimental data were fit to the Langmuir equation, with maximum uptake qmax equal to 549.2 mg/g. The qmax value found for IgG in Capto MMC was quite high as compared to other chromatographic techniques that employ single modes of interaction. Regarding elution, the best conditions were obtained with acetate buffer (56.40 mmol/L), pH 5.2 and 0.2 mol/L NaCl. An ultimate recovery of 46.96% for high-purity IgG was achieved. Thus, the effectiveness of Capto MMC for IgG adsorption and recovery could be confirmed. Moreover, electrophoretic runs in the human serum indicated that although co-elution of HSA and IgG proteins occurs, substantial HSA removal and a high IgG recovery were achieved in the elution step.

Chemotherapy versus support cancer treatment in advanced gastric cancer: a meta-analysis.

The aim of the present study was to compare the efficacy of chemotherapy and support treatment in patients with advanced non-resectable gastric cancer in a systematic review and meta-analysis of randomized clinical trials that included a comparison of chemotherapy and support care treatment in patients diagnosed with gastric adenocarcinoma, regardless of their age, gender or place of treatment. The search strategy was based on the criteria of the Cochrane Base, using the following key words: 1) randomized clinical trials and antineoplastic combined therapy or gastrointestinal neoplasm, 2) stomach neoplasm and drug therapy, 3) clinical trial and multi-modality therapy, 4) stomach neoplasm and drug therapy or quality of life, 5) double-blind method or clinical trial. The search was carried out using the Cochrane, Medline and Lilacs databases. Five studies fulfilled the inclusion criteria, for a total of 390 participants, 208 (53%) receiving chemotherapy, 182 (47%) receiving support care treatment and 6 losses (1.6%). The 1-year survival rate was 8% for support care and 20% for chemotherapy (RR = 2.14, 95% CI = 1.00-4.57, P = 0.05); 30% of the patients in the chemotherapy group and 12% in the support care group attained a 6-month symptom-free period (RR = 2.33, 95% CI = 1.41-3.87, P < 0.01). Quality of life evaluated after 4 months was significantly better for the chemotherapy patients (34%; RR = 2.07, 95% CI = 1.31-3.28, P < 0.01) with tumor mass reduction (RR = 3.32, 95% CI = 0.77-14.24, P = 0.1). Chemotherapy increased the 1-year survival rate of the patients and provided a longer symptom-free period of 6 months and an improvement in quality of life.

Chemotherapy versus support cancer treatment in advanced gastric cancer: a meta-analysis

The aim of the present study was to compare the efficacy of chemotherapy and support treatment in patients with advanced non-resectable gastric cancer in a systematic review and meta-analysis of randomized clinical trials that included a comparison of chemotherapy and support care treatment in patients diagnosed with gastric adenocarcinoma, regardless of their age, gender or place of treatment. The search strategy was based on the criteria of the Cochrane Base, using the following key words: 1) randomized clinical trials and antineoplastic combined therapy or gastrointestinal neoplasm, 2) stomach neoplasm and drug therapy, 3) clinical trial and multi-modality therapy, 4) stomach neoplasm and drug therapy or quality of life, 5) double-blind method or clinical trial. The search was carried out using the Cochrane, Medline and Lilacs databases. Five studies fulfilled the inclusion criteria, for a total of 390 participants, 208 (53 percent) receiving chemotherapy, 182 (47 percent) receiving support care treatment and 6 losses (1.6 percent). The 1-year survival rate was 8 percent for support care and 20 percent for chemotherapy (RR = 2.14, 95 percent CI = 1.00-4.57, P = 0.05); 30 percent of the patients in the chemotherapy group and 12 percent in the support care group attained a 6-month symptom-free period (RR = 2.33, 95 percent CI = 1.41-3.87, P < 0.01). Quality of life evaluated after 4 months was significantly better for the chemotherapy patients (34 percent; RR = 2.07, 95 percent CI = 1.31-3.28, P < 0.01) with tumor mass reduction (RR = 3.32, 95 percent CI = 0.77-14.24, P = 0.1). Chemotherapy increased the 1-year survival rate of the patients and provided a longer symptom-free period of 6 months and an improvement in quality of life.