Secondary effluent reclamation: combination of pre-treatment and disinfection technologies.

A study was carried out to evaluate the efficiency of secondary effluent additional treatment, using a combination of pre-treatments (ring filter, physico-chemical and infiltration-percolation) followed by disinfection methods (chlorine dioxide, peracetic acid and ultraviolet light). Three different indicator microorganisms were determined: E. coli, total coliforms and somatic bacteriophages. The results show better efficiency of physico-chemical and infiltration-percolation processes. Bacteriophages were eliminated to a lesser extent than bacterial indicators in all the treatment systems. Chlorine dioxide and peracetic acid seems to be more efficient in disinfection than ultraviolet light when a ring filter is the pre-treatment used. For the same doses and contact times, the efficiency of the disinfection methods is higher when the pre-treatment used is the physico-chemical or the infiltration-percolation system. The final effluent quality from the physico-chemical treatment train and the infiltration-percolation treatment train, followed by the disinfectants, achieves an E. coli content that allows the reuse in most of the uses described in the Spanish legislation for wastewater reuse.

Wastewater reclamation through a combination of natural systems (infiltration-percolation and constructed wetlands): a solution for small communities.

The decision on technologies used for reclaiming wastewater appears as important as a consequence of the implications on the economic, environmental and health conditions of societies. The problem arises when deciding how to deal with wastewater in small communities, because the costs of implementing and operating small, intensive wastewater treatment plants are unacceptable and can lead to financing and operation problems. Extensive treatment systems can be a good solution, where space is available. This paper presents the combination of two soft technologies (infiltration-percolation and constructed wetlands) to treat and reclaim wastewater. The obtained results show that the infiltration-percolation effluent presents a quality enough to be reused for irrigation of industrial crops, nurseries, fodder, cereals and oleaginous seeds, ornamental flower production; industrial cooling; impoundments, water bodies, and streams for recreational use in which the public's contact with the water is not permitted; and irrigation of forested areas, landscape areas and restricted access areas. Moreover, the combination of infiltration-percolation and constructed wetlands increases the list of final reclamation to the following: irrigation of pasture for milk or meat animals, crops for canning industry, crops not raw-consumed, fruit trees except by sprinkling, aquaculture; and aquifer recharge by localised percolation through the soil.

Wastewater reclamation systems in small communities.

The demands established in the rules and regulations by the administration in Catalonia seem to exclude small communities from wastewater reclamation and reuse, due to the comparatively high costs associated with the practice at small scale. In the framework of the DRAC project (Demonstration on Wastewater Reclamation and Reuse in Catalonia) two different pre-treatment systems, one extensive (infiltration-percolation) and another intensive (ring filter), each one followed by chlorine dioxide disinfection, were tested in order to be applied for small communities wastewater reclamation and reuse. The results of this study show that infiltration-percolation systems remove very efficiently physico-chemical contaminants and microorganisms. The ring filter system does not show a significant removal rate of contaminants, The use of infiltration-percolation as a pre-treatment for advanced chemical disinfection allows reducing the dose of disinfectant and the contact time needed to achieve a specific water quality, and diminishes disinfection byproducts (DBPs) generation. Therefore, this reclamation line is suitable for small communities due to its efficiency and low cost. However, further studies are needed in relation to the removal mechanisms of microorganisms, organic compounds in IP systems and the possible DBPs formation using chlorine dioxide.

Wastewater infiltration percolation for water reuse and receiving body protection: thirteen years' experience in Spain.

Infiltration percolation (IP) is an extensive technology to treat primary or secondary effluents of small and middle size communities before reuse or disposal to sensitive receiving bodies. Thirteen years of implementation of IP in Spain has highlighted the necessity to abide by defined design and construction rules and operation conditions in order to achieve consistently the treatment objectives and guarantee a long lasting treatment capacity. From this experience, high care should be taken of (i) the characteristics of the sand constituting the filter, (ii) the drainage conditions, (iii) the influent spreading over the infiltration surface and (iv) the risks related to recurrent overloading. Simple monitoring measures are suggested in order to improve the reliability of IP plants.

Müllerian agenesis: etiology, diagnosis, and management.

UNLABELLED: Mullerian agenesis, a congenital malformation of the genital tract is the second most common cause of primary amenorrhea. Its etiology is poorly understood but it may be associated with renal, skeletal, and other abnormalities. The diagnosis is often made either radiologically or laparoscopically in patients in whom hormonal and karyotypic investigations for primary amenorrhea are normal. Two-dimensional ultrasound is not a reliable method of diagnosis, as exemplified by the two cases presented in this review; however, three-dimensional ultrasound may be a more sensitive diagnostic tool. The management is varied, but we conclude that the treatment of choice should be a nonsurgical approach aimed at creating a neovagina. Because of the implications for reproduction, these patients require psychological support, which should be offered as part of therapy. TARGET AUDIENCE: Gynecologists and Family Physicians LEARNING OBJECTIVES: After completion of this article, the reader will be able to describe the pathophysiology and clinical presentation of mülerian agenesis and to list the other abnormalities associated with this condition and to outline potential treatment options for a patient with müllerian agenesis.

[Immunogammagraphy with anti-CEA and anti-TAG-72 monoclonal antibodies in the diagnosis of colorectal carcinoma]. / Inmunogammagrafía con anticuerpos monoclonales anti-CEA y anti-TAG-72 en el diagnóstico del carcinoma colorrectal.

BACKGROUND: The purpose of nuclear medicine in the evaluation of colorectal carcinoma is to complete the current diagnostic protocol, by means of monoclonal antibodies (MoAb) against tumoral antigens labelled with radioactive isotopes and performing an immunoscintigraphy. PATIENTS AND METHODS: Immunoscintigraphies have been performed to 143 patients with colorectal carcinoma. Group I: antiCEA MoAb 99mTc-BW 431/26 (72 patients with 74 lesions, 48 primary tumors and 26 recurrences); group II: antiTAT-72 MoAb 111In-CYT-103 (71 patients with 75 lesions, 28 primary tumors and 47 recurrences). All positive images, not corresponding to physiological distribution of MoAb, have been considered as pathological. RESULTS: The sensitivity in the diagnosis of primary tumors in group I was worse than in group II (54.2% vs 66.7%). If rectum tumors were excluded, the sensitivity increased to 80% and 85.7%, respectively. In the suspicion of recurrences, if only lesions confirmed at surgery were considered, the sensitivity was 75% in group I and 89.7% in group II. The immunoscintigraphy has been the only technique able to diagnose recurrences in 4/23 cases from group I and 14/32 from group II. In liver, considering as metastases only hot images, the sensitivity is very low in group I (44.4%) and null in group II. No relationship has been found between tumour markers levels and the immunoscintigraphic result. CONCLUSIONS: Immunoscintigraphy is useful in patients with colorectal carcinoma, especially in the case of recurrences and it is a complementary technique to other diagnostic procedures.

[The therapeutic posture in desmoid tumor]. / Actitud terapéutica ante el tumor desmoide.

BACKGROUND: The desmoid tumor is a histologically benign neoplasm originating in muscular-aponeurotic structures and possesses a high tendency of local recurrence. The aggressive nature of the tumor obliges radical surgery to be performed principally in extra-abdominal tumors. METHODS: Twelve patients were treated from 1983 to 1993. The treatments performed prior to and after histologic diagnosis, the time of evolution when radical treatment was carried out upon diagnosis and the evolution after treatment were evaluated. RESULTS: Of the patients with desmoid tumor 8 were males with a mean age of 29.9 +/- 12.5 years. In eleven cases the presentation was as a tumor and was of pain in only one case. All the patients were surgically treated with a total of 27 interventions being carried out. Three patients also received pharmacologic treatment with tamoxifen, in 2 cases associated to sulindac. In two radiotherapy was used but not as a first line treatment. Following a mean follow up of 38 +/- 17 months no mortality has been registered but 5 patients are not disease free. CONCLUSIONS: The therapeutic attitude to the desmoid tumor should be radical surgery in both the primary tumor and the recurrences with medical treatment being performed in specific situations.

Delayed rejection of heart allografts after extracorporeal donor-specific liver hemoperfusion. Role of Kupffer cells.

Liver allografts have a privileged status in regard to acute rejection. In this experimental study, we have analyzed the immunosuppressive effects of an extracorporeal liver hemoperfusion. In the LEW-to-BN combination of inbred rats, donor-specific liver hemoperfusion can significantly delay acute rejection of heart allografts. Analysis of the immunological status of these animals revealed a significant decrease in donor-specific lymphocytotoxic antibodies and in cytotoxic T lympholysis. Reactivity in mixed lymphocyte culture was normal. After third-party (DA) liver hemoperfusion or after donor-specific (LEW) splenic hemoperfusion, prolongation of heart allograft survival was moderate. Previous blockade of Kupffer cells suppressed the effects of donor-specific liver hemoperfusion. These results suggest that the sequestration by Kupffer cells of a clone of cytotoxic T cells and/or lymphocytotoxic antibodies may explain the immunosuppressive effects of donor-specific liver hemoperfusion.