Social constructivism and capacity building for environmental governance

The concept of capacity building for environmental protection and management refers to the process by which the abilities of societies to identify and solve environmental problems are developed. This work assumes a social constructivist perspective to the process of capacity building for environmental governance and thus depicts it as critically dependent on broader processes of political and socioeconomic modernization. In an attempt to depict such a process, a heuristic device is put forward as a model of capacity analysis. A theoretical discourse and new institutionalist perspectives are used to test such a model on a theoretical plane. Some preliminary conclusions are drawn from this theoretical exercise.     

Local staging with CT of tumors of the upper urothelium

OBJECTIVE: To evaluate the ability of computerized tomography (CT) to stage transitional cell carcinoma of the upper urinary tract. METHODS: 29 transitional cell carcinoma of the upper urinary tract submitted to nephroureterectomy were retrospectively evaluated. All 29 tumors had preoperative CT scans performed to stage the lesion. The pathological staging was compared to that of CT. RESULTS: 10 of the 29 tumors had CT evidence of tumor extension and 19 had localized noninvasive tumor on CT. Of the 10 patients with CT findings of tumor extension, 2 (20%) had superficial tumors and 8 (80%) had tumors that invaded into the adventitial fat, renal parenchyma or perirenal fat (pT3, pT4). Of the 19 patients with localized noninvasive tumor on CT, 13 (68%) had superficial tumors and 6 (32%) had pT3 or pT4 tumors. CT sensitivity for tumor invasion was 57% with a specificity of 87.5%. CONCLUSIONS: Our analysis shows that CT is of limited value in staging these tumors. When CT demonstrates direct tumor extension through the renal pelvic or ureteral wall, it is a sensitive indicator of high-stage tumor. However, the results obtained in low stage tumors must be viewed with caution.     

Visual functions after photorefractive keratectomy

1. 45 myopes (-3.0 to -6.0 D) were examined before and 1 and 6 months after photorefractive keratectomy (PRK). Visual acuity (VA) was tested using Snellen and logMAR charts. Contrast sensitivity (CS) was measured using a computerized system. 2. Preoperative best corrected VA (BCVA) in myopes was significantly lower in comparison with a control group using logMAR charts only. A reduction of BCVA by both methods at 1. month and its return after 6 months nearly to original values was noted. 3. Significantly lower values of CS were found in patients before PRK compared to the control group. After 1 and 6 months stayed the values on preoperative level.     

Interactions in the complement-mediated lysis of blood group AB erythrocytes sensitized simultaneously with anti-A and anti-B monoclonal antibodies

The lysis of group AB erythrocytes by human complement was studied by different anti-A and anti-B IgM monoclonal antibodies (mabs) in a 51Cr-release assay. The concentration of membrane-bound immunoglobulin was detected by ELISA, and the amount of C1q and C3 bound to sensitized red cells was measured by using purified, 125I-labelled molecules. We have demonstrated that there is an exponential relationship between the concentration of the sensitizing IgM mabs and C1q binding to the sensitized AB cell. The efficiency of binding was related to the number of antibodies bound; thus, anti-A sensitized cells bound 3-6 times more C1q than anti-B sensitized cells did. AB cells, on the other hand, bound similar amounts of C3 whether anti-A or anti-B was present. The lytic efficiencies of the various IgM mabs during short incubation times were different, suggesting that the complement activation rates vary widely with different antibodies on the AB cell membrane. The binding of C1q to an antibody-sensitized target activates a cascade, whose components may migrate away from the sensitizing antibody; interactions between the activation processes generated by the anti-A and anti-B antibodies may thus occur. Choosing appropriate pairs of anti-A and anti-B mabs for the simultaneous sensitization of AB cells has indeed resulted in stimulation in some and inhibition in other combinations of mabs. It is suggested that stimulation is observed when the activated intermediates are produced in excess, whereas inhibition occurs when a shortage of activated intermediates prevents mutual utilization.     

A column centrifugation method for the reconstitution in liposomes of the mitochondrial F0F1 ATP synthase/ATPase

A method for reconstitution of membrane proteins into unilamellar liposomes is described. The model enzyme was the F0F1 ATP synthase from mitochondria when in complex or free from its inhibitor protein. The enzymes were first solubilized with either of two detergents, i.e., n-dodecyl-beta-D maltoside or lauryldimethylamine oxide. After solubilization, the enzymes were passed through a column of Sepharose-AH using an ADP/sodium cholate selective elution buffer. The enzymes recovered from the column were subsequently passed through a centrifuge column of Sephadex G-50 fine. The eluate contained liposomes in which the F0F1 complex (with and without inhibitor protein) had been reconstituted. The reconstituted enzymes were capable of hydrolyzing ATP with formation of electrochemical H+ gradients. They also catalyzed the ATP-Pi exchange reactions. Thus the F0F1 complex which is formed by 18 subunits can be rapidly reconstituted into liposomes in a fully functional state. Moreover the data show that the interactions between the enzyme and its inhibitor protein are not perturbed in the reconstitution procedure.