Influence of temperature on the start-up of membrane bioreactor: kinetic study.

The start-up phase of a membrane bioreactor (MBR) for municipal wastewater treatment was studied to determine the effect of temperature on the organic matter removal and heterotrophic kinetics. The MBR system was analyzed during four start-up phases with values of hydraulic retention time (HRT) of 6 h and 10 h, mixed liquor suspended solids (MLSS) concentrations of 4,000 mg L-1 and 7,000 mg L-1 in the steady state, and temperature values of 11.5, 14.2, 22.9 and 30.1 °C. The influence of temperature on the biological process of organic matter removal was determined through the Arrhenius equation and Monod model. At the most favorable operation conditions of HRT (10 h) and MLSS (7,000 mg L-1) corresponding to phase 4, the effect of these variables dominated over the temperature. Heterotrophic biomass from phase 2 (HRT = 10 h, MLSS = 4,000 mg L-1 and T = 30.1 °C) had the highest values of chemical oxygen demand (COD) degradation rate (rsu,H), implying less time to remove organic matter and shorter duration of the start-up phase.

Advanced methods for the elimination of microorganisms in industrial treatments: potential applicability to wastewater reuse.

Because of the growing need to eliminate undesirable microorganisms in different industrial treatments, mainly in the food and agricultural sector and the pharmaceutical industry, a number of increasingly effective systems for disinfection to eliminate microorganisms have been devised. This article analyzes different methods to eliminate and/or significantly reduce the number of microorganisms in industrial contexts and in environmental engineering. Although, in the past, thermal treatments had been used most frequently for microbial elimination, the method is costly and has the disadvantage of modifying the organoleptic and/or physicochemical properties of the food products. For this reason, new technologies rapidly are being developed, such as high-intensity pulsed electric fields, high-pressure systems, ultrasounds, and irradiation, which effectively eliminate microorganisms without deteriorating the properties of the product. These emerging technologies are potentially applicable in the field of environmental engineering.

Cytoreduction combined with intraperitoneal hyperthermic perfusion chemotherapy in advanced/recurrent ovarian cancer patients: The experience of National Cancer Institute of Milan.

AIMS: We report the effects of cytoreductive surgery (CRS) and intraperitoneal hyperthermic perfusion (IPHP) in the treatment of advanced/recurrent epithelial ovarian cancer (EOC) on survival, morbidity and mortality. PATIENTS: Forty EOC patients were studied. Median age was 52.5 years (range: 30-68) and median follow-up 26.1 months (range: 0.3-117.6). Most patients presented advanced disease (stage III/IV). Previous systemic chemotherapy included cisplatin-based, taxol-based or taxol/platinum containing regimens. RESULTS: After the CRS, 33 patients presented no macroscopic residual disease. Five-year overall survival was 15%; the mean overall and progression-free survivals were 41.4 and 23.9 months, respectively. The morbidity, toxicity and mortality rates were 5%, 15% and 0%, respectively. CONCLUSION: Our results suggest that CRS + IPHP merits further evaluation by a formal prospective trial.

Heparin solubilizes asymmetric acetylcholinesterase from rat neuromuscular junction.

We are interested in the factors involved in the anchorage of acetylcholinesterase (AChE) to the synaptic basal lamina. Here, we report studies showing that heparin, a sulfated glycosaminoglycan, specifically solubilized AChE from endplate regions of rat diaphragm muscle. Of the several molecular forms of AChE present in that region, heparin only released the asymmetric A12 and A8 forms of the enzyme. Our results strongly support the involvement of heparin-like macromolecules in the in vivo immobilization of the collagen-tailed forms of AChE to the basal lamina of the neuromuscular junction.

A cluster of pediatric metallic mercury exposure cases treated with meso-2,3-dimercaptosuccinic acid (DMSA)

Nine children and their mother were exposed to vapors of metallic mercury. The source of the exposure appears to have been a 6-oz vial of mercury taken from a neighbor's home. The neighbor reportedly operated a business preparing mercury-filled amulets for practitioners of the Afro-Caribbean religion Santeria. At diagnosis, urinary mercury levels in the children ranged from 61 to 1,213 microg/g creatinine, with a geometric mean of 214.3 microg/m creatinine. All of the children were asymptomatic. To prevent development of neurotoxicity, we treated the children with oral meso-2,3-dimercaptosuccinic acid (DMSA). During chelation, the geometric mean urine level rose initially by 268% to 573.2 microg mercury/g creatinine (p<0.0005). At the 6-week follow-up examination after treatment, the geometric mean urine mercury level had fallen to 102.1 microg/g creatinine, which was 17.8% of the geometric mean level observed during treatment (p<0.0005) and 47.6% of the original baseline level (p<0.001). Thus, oral chelation with DMSA produced a significant mercury diuresis in these children. We observed no adverse side effects of treatment. DMSA appears to be an effective and safe chelating agent for treatment of pediatric overexposure to metallic mercury.

Gastroplasty conversion to Roux-en-Y gastric bypass at the lesser curvature due to weight loss failure.

From January 1982 to April 1984, 20 patients with lesser curvature gastroplasty had conversion to Roux-en-Y gastric bypass at the lesser curvature for failure to lose more than 50 per cent of excess body weight within 12 months of the original gastroplasty. The average excess weight of these patients before gastroplasty was 103 lb, and the average excess weight before conversion to gastric bypass was 73 lb. The average weight loss after gastric bypass was doubled within 6 to 15 months. Only one patient failed to lose weight after conversion to gastric bypass, and this patient had endocrine problems. Late surgical complications occurred in two patients (10%); one had cholecystectomy and the other had vagotomy and hiatus hernia repair. There were no mortalities in this series.

Extracts of Anacardium occidentale (cashew) pollen in patients with allergic bronchial asthma.

Allergic reactions to the pollen of trees is among the most prevalent allergic sensitivities. The cashew tree grows in abundance in the northeast region of the Brazil, mainly in Fortaleza city, in state of the Ceará. It flowers once a year between August and October. This is the first study conducted to establish the possible role of the cashew pollen extract in causing skin test reactivity in patients with allergic asthma. A stock solution of pollen extract was prepared with the standard weight/volume method for intradermal skin tests and for the protein content of the extract, estimated with the use of Folin phenol reagent and a spectrophotometer. Ten nonallergic volunteers and 80 subjects with allergic asthma, as documented by previous positive skin test reactions to various pollens, were studied. All of the 80 patients (100%) had positive test reactions (grade III and grade IV reactions). None of the control subjects (n = 10) had positive responses to the intradermal tests. This study provided us with knowledge of an additional pollen extract of the Anacardium occidentale, which could provoke skin test reactivities in asthmatic individuals from the northeastern area of Brazil. The results suggest a relationship between the period of flowering of the cashew tree and the increased number of allergic asthma cases.

A program evaluation study of a nursing home operated as a modified therapeutic community for chemically dependent persons with AIDS. Project Samaritan AIDS Services, Inc.'s Residential Health Care Facility, Highbridge Section, Bronx, NY.

An interagency evaluation of the treatment effectiveness of a speciality nursing home (NH) run as a therapeutic community (TC) for residents diagnosed with acquired immunodeficiency syndrome (AIDS) and substance abuse/dependence (SA/D) was conducted. A total of 79 chemically dependent men and women with AIDS were: (a) administered the Tennessee Self-Concept Scale (TSCS; Roid & Fitts, 1991) at initial testing (T(1)) and 8 months after their initial testing (T(2)); and (b) assessed on specific physical health indicators (i.e. , weight, CD-4 count, and viral load) and other treatment outcomes (e.g., abstinence) over the same two time periods. The TSCS results identified a valid and invalid TSCS test group and further distinguished among three subgroups of invalid responders. Significant improvements were observed from T(1) testing to T(2) testing on the TSCS, on the physical health indicators, and on other treatment outcomes. The need for additional and continued mental health services for this population was noted.

Ovarian germ cell cancer: clinicopathologic analysis and outcome of 31 cases.

AIMS: The aim of the study was to evaluate some clinicopathologic characteristics and the outcome of patients with ovarian germ cell cancer (OGCC) treated with cisplatin-based chemotherapy. METHODS: It was a clinical retrospective study. The clinical charts of 31 patients with OGCC assisted at the Department of Obstetrics and Gynecology of the State University of Campinas, Brazil, from January 1986 to June 1997 were reviewed. RESULTS: Ten patients had dysgerminoma and 21 patients nondysgerminomatous tumors. Women with dysgerminoma and nondysgerminomatous tumors did not present differences regarding surgical staging, age, ascites or residual tumor after the initial surgery. Frozen section, performed in 16 patients, showed some discrepancy with paraffin histology diagnosis in 8 patients. Platinum-based chemotherapy was used in 5/10 patients with dysgerminoma and in 17/21 patients with nondysgerminomatous tumors, with a 5-year survival of 100% for the dysgerminoma and 53% for the nondysgerminomatous group. CONCLUSIONS: Women with dysgerminoma and nondysgerminomatous tumors did not present differences regarding clinicopathologic characteristics. The prognosis for patients with dysgerminoma was better than for those with nondysgerminomatous tumors. Frozen section had a high error rate in diagnosing OGCC intraoperatively.

[Recommendations on making decisions and end of life care in neonatology]. / Recomendaciones sobre toma de decisiones y cuidados al final de la vida en neonatología.

Healthcare-professionals who work in neonatal units believe that a very important part of their work is the care of sick newborns, and their families if the neonate has an incurable disease or will die. The effort is focused on preventing disproportionate and unnecessary treatments that result in pain and discomfort, and also separate the child from his family. These situations usually occur when the infant has a terminal illness, extreme immaturity with complications, or severe birth defects. In this paper, the Ethics Working Group of the Spanish Society of Neonatology reflects on decision making at this time of life. The ethical aspects are reviewed, including, limiting treatment, the basis of decision-making process (that should include adequate information), the relationship of trust, and deliberation between parents and professionals to make the right decision. It highlights the importance of caring for the family in a complex situation and of great suffering, when faced with the recommendation of professionals to limit treatment because their child suffers from a disease with a poor prognosis. The care of the sick neonate care at the end of life, and their families requires a considerable effort, dedication and training of all health personnel. The repeated experience of being close to suffering and death can adversely affect the professionals involved. Finally, there is mention of the legal aspects of limiting treatment, how to perform and document decision process, the withdrawal of life support, assessment of symptoms and pain control and sedation.

Atypical glandular cells: criteria to discriminate benign from neoplastic lesions and squamous from glandular neoplasia.

OBJECTIVE: To evaluate the presence of some criteria in cervical smears with atypical glandular cells and their correlation with histological patterns to identify pre-neoplastic and neoplastic lesions. METHODS: Seventy-three women referred with an atypical glandular cell smear, who had undergone conization or hysterectomy, were included in this study. Referral Pap smears were reviewed using the set of 27 cyto-morphological criteria that was correlated with the histological diagnosis. RESULTS: Histological results showed intraepithelial or invasive neoplasia in 35 (48%) cases and benign lesions in 38 (52%) cases. After logistic regression and decision tree analysis an increased nuclear/cytoplasmic ratio and the presence of dyskeratotic cells were strongly associated with intraepithelial or invasive neoplasia and the differential cyto-morphological criteria for glandular lesions were decreased cytoplasm, irregular nuclear membranes and the presence of nucleoli. CONCLUSION: The analysis of individual cyto-morphological criteria can better predict intraepithelial or invasive neoplasia and differentiate glandular from squamous lesions.

An in vitro model showing different rates of substrate cycle for phosphofructokinases of Escherichia coli with different kinetic properties.

An in vitro assay model is introduced for the coupled assay of phosphofructokinase (PFK) and fructose-bisphosphatase. The model is applied to the study of three PFK of Escherichia coli: two isoenzymes, phosphofructokinase-1 (PFK-1) and phosphofructokinase-2 (PFK-2), and a mutant form of phosphofructokinase-2 (PFK-2*). Results show that for a variety of conditions the PFK-1/fructose-bisphosphatase pair gives the lowest and the PFK-2*/fructose-bisphosphatase pair the highest rates of substrate cycle, with the PFK-2/fructose-bisphosphatase pair in an intermediate position. The effects of variables such as maximum activity ratios and MgATP concentration were explored. The possible role of MgATP in decreasing the futile cycle of the PFK-2/fructose-bisphosphatase pair is described. The results are discussed in terms of possible metabolic consequences of PFK-2* and of predictions of the model to be tested in vivo.

Interaction of heparin with multimolecular aggregates of acetylcholinesterase.

It has been reported previously that heparin, a sulfated glycosaminoglycan, releases the asymmetric 16 S form of acetylcholinesterase (AChE) from cholinergic synapses. Here it is shown that heparin releases the synaptic AChE not as individual 16 S species but as multimolecular aggregates (30 S) of such molecules. Heparin is able to convert low-ionic strength AChE aggregates into a heparin type of AChE aggregates. Our results suggest that the AChE aggregates detached by heparin are likely to be the physiologically important state of aggregation of the 16 S AChE form in the synaptic basal lamina.

Slow axoplasmic transport: a fiction?

Ribosomes have not been observed in axoplasm. This had led to the notions that the perikaryon is the only source of neuronal proteins and that the axoplasm is supplied by a (slow) transport mechanism. However, we question these two notions because they are unable to give an account of real neurones in accordance with the body of biological knowledge. We point out, for example, that the synthetic rate of perikarya or the life span of axoplasmic proteins should be beyond known ranges for animal cells and that a uniform axon is unlikely to result if it is fed from one end. We propose an alternative view for the maintenance of the axon which accepts the controversial idea of axoplasmic synthesis of proteins; as a result, the slow transport becomes unnecessary. Our view gives a qualitative account of the observations dealing with the maintenance of the axoplasm. To account for the phenomenology in a more quantitative fashion, a computer simulation was carried out where the equations of the program provided only for axoplasmic synthesis of proteins; the set of curves retrieved were in good agreement with experimental findings believed so far to support the notion of slow transport. In conclusion, we think that the notion of "slow axoplasmic transport" has been a misinterpretation of good observations because the frame of reference was incomplete in not providing for axoplasmic synthesis of proteins.

A new method of assessing rates of the futile cycle during glycolytic and gluconeogenic metabolism.

A method for assessing rates of the futile cycle is presented, and it is illustrated in vitro. Glycolytic- and gluconeogenic-type futile cycles are simulated for the reactions catalyzed by phosphofructokinase (EC 2.7.1.11) and fructose-1,6-bisphosphatase (EC 3.1.3.11) in assays systems in which the cycle rates in either direction can be varied and determined. While either system is sustaining a net flux of carbons in a given direction, the flux of radioactively labeled carbons in the opposite direction is determined. Different cycle rates are obtained by varying phosphofructokinase activity while keeping fructose-1,6-bisphosphatase activity constant in the "gluconeogenic" simulation and varying fructose-1,6-bisphosphatase while keeping phosphofructokinase activity constant in the "glycolytic" simulation. A direct, linear relationship was found between the cycle rate and the radioactive labeling of fructose 1,6-bisphosphate from [U-14C]glucose 6-phosphate during net gluconeogenic carbon flux. Also, a direct, linear relationship was found between cycle rate and radioactive labeling of fructose-6-P from [U-14C]fructose-1,6-bisP during net glycolytic carbon flux. The applicability, advantages, and problems of the method are discussed.

Gastric bypass: Roux-en-Y gastrojejunostomy from the lesser curvature.

We describe a new technique for the surgical treatment of exogenous morbid obesity. The stomach is partitioned from the angle of His toward the lesser curvature, and a Roux-en-Y proximal jejunal limb drains the proximal gastric pouch, which is 25 to 35 ml in capacity. By use of the enteroanastomosis (EEA) or the intraluminal (ILS) stapling instrument for the gastrojejunostomy from the lesser curvature of the stomach, the functional reliability, vascular integrity, and ease of construction of the stoma have been improved. We performed the gastric bypass operation on 300 consecutive patients, 268 women and 32 men, over a two-year period beginning in June 1979. The patients' average admission weight was 126 kg. Diseases associated with obesity were observed in 57% of the patients, and concomitant operations were performed in 29%. The average weight loss at 6, 12, 18, and 24 months was 37.0, 48.5, 51.5, and 52.0 kg, respectively. Early and late complications occurred in 37 patients (12%), requiring 40 reoperations. Two deaths (0.6%) occurred within the 30 months' of observation.

Neural 16S acetylcholinesterase is solubilized by heparin.

The effect of heparin, a sulphated glycosaminoglycan, on the solubilization of rat sciatic-nerve acetylcholinesterase (acetylcholine acetylhydrolase; AChE; EC 3.1.1.7) was studied. It was found that heparin solubilized esterase activity from ligated nerves. Sedimentation analysis revealed this activity to be mainly the 16S form. Chondroitin sulphate did not solubilize AChE activity, and protamine eliminated the solubilizing effect. Our results suggest the involvement of sulphated glycosaminoglycans in the intra-axonal localization and transport of 16S AChE.