Propachlor removal by Pseudomonas strain GCH1 in an immobilized-cell system

A bacterial strain capable of growing on propachlor (2-chloro-N-isopropylacetanilide) was isolated from soil by using enrichment and isolation techniques. The strain isolated, designated GCH1, was classified as a member of the genus Pseudomonas. Washed-cell suspensions of strain GCH1 accumulated N-isopropylacetanilide, acetanilide, acetamide, and catechol. Pseudomonas strain GCH1 grew on propachlor with a generation time of 4.2 h and a rate of substrate utilization of 1.75 +/- 0.15 micromol h(-1). Gene expression did not require induction but was subject to catabolite expression. Acetanilide was a growth substrate with a yield of 0.56 +/- 0.02 mg of protein micromol(-1). GCH1 strain cells were immobilized by adsorption onto a ceramic support and were used as biocatalysts in an immobilized cell system. Propachlor elimination reached 98%, with a retention time of 3 h and an initial organic load of 0.5 mM propachlor. The viability of immobilized cells increased 34-fold after 120 days of bioreactor operation.

How does the microbial load affect the quality of equine cool-stored semen?

Contaminating bacteria present in stallion ejaculates may compromise sperm quality during storage. Different procedures have been used to reduce the load of microorganisms in semen and avoid bacterial growth during storage. The aims of this study were: 1) to evaluate different techniques to eliminate bacteria in semen 2) to study the relationship between total microflora load (TML) and ROS production; and 3) to determine if TML affects the functionality of cool-stored sperm. Ejaculates from 11 stallions were split and processed in 3 ways: A. extended semen; B. conventional centrifuged semen, and C. Single layer centrifugation through Androcoll-E (SLC). All samples were preserved in INRA 96 at 5 °C for 72 h. Aliquots from native semen and from different treatments were taken for bacteriological analysis at T0, T24, T48 and T72h of storage and Total microbial load (TML: CFU (colony-forming units/ml) was calculated. The ROS production (dichlorodihydrofluorescein diacetate for H₂O₂, dihydroethidium for superoxide anion and CellROX deep red for total ROS), viability (YO-PRO-1-Ethidium) and lipid peroxidation (BODIPY-C11) were assessed by flow cytometry, and motility by CASA. The bacteria isolated were Corynebacterium spp, Arcanobacterium spp, Bacillus spp, Dermobacter, Staphylococcus spp, Streptococcus spp, Penicilium spp. TML of semen showed correlations with live sperm (r: -0.771), dead sperm (r: 0.580), H₂O₂ production (r: 0.740), and total ROS production (CellROX (+)) (r: -0.607), Total motility (r: 0.587), Progressive motility (r: -0.566), VCL (r: -0.664), VSL (r: -0,569), VAP (r: -0.534) (p ≤ 0.05). SLC removed 99.34% of the microbial load, which was assicated with a significanlty reduced H₂O₂ production (p ≤ 0.05). However, only samples treated with Androcoll-E had a higher total ROS production (CellROX +) (p ≤ 0.05). These results suggest that CellROX stain probably identifies superoxide production rather than H₂O₂ and this higher superoxide production may reflect an intense sperm functionality. The bacterial load increased the production of H₂O₂ in cool-stored semen which was associated with lower tolerance to refrigeration. SLC was the sperm processing technique that was most efficient at removing bacteria, reducing H₂O₂ production and selecting the most functional sperm.

Case-based learning of plans and goal states in medical diagnosis

We introduce a case-based system, BOLERO, that learns both plans and goal states. The major aim is that of improving the performance of a rule-based diagnosis system by adapting its behavior using the most recent information available about a patient. On the one hand BOLERO gets knowledge from cases in the form of diagnostic plans that are represented as sequences of decision steps. The advantages of this representation include: (1) retrieval and adaptation of parts of plans (steps) appropriate to the current problem state; (2) generation of new plans not previously available in memory; and (3) learning from experience, both from successful or failed plans. On the other hand, since goal states are sets of final diagnosis likelihoods they are not known beforehand, i.e. goal states are not defined and the system has to learn to recognize them. For this reason BOLERO has a case-based method that uses solutions of past cases to recognize a diagnostic state as a goal state of a new planning problem. BOLERO and a rule-based system are integrated into a meta-level architecture in which we emphasize the collaboration of both systems in solving problems. The rule-based system executes the plans generated by BOLERO. As a consequence of the execution of plans, the rule-based system furnishes BOLERO with new information with which BOLERO can generate a new plan to adapt the reasoning process of the rule-based system into correspondence with the recent available data. All the methods have been designed to be useful for medical diagnosis and have been tested in the domain of diagnosing pneumonia.

A one-stage system with partial nitritation and anammox processes in the moving-bed biofilm reactor

The ability of bacterial cultures to create biofilm brings a possibility to enhance biological wastewater treatment efficiency. Moreover, the ability of Anammox and Nitrosomonas species to grow within the same biofilm layer enabled a one-stage system for nitrogen removal to be designed. Such a system, with Kaldnes rings as carriers for biofilm growth, was tested in a technical pilot plant scale (2.1 m(3)) at the Himmerfjärden Waste Water Treatment Plant (WWTP) in the Stockholm region. The system was directly supplied with supernatant originating from dewatering of digested sludge containing high ammonium concentrations. Nearly 1-year of operational data showed that during the partial nitritation/Anammox process, alkalinity was utilised parallel to ammonium removal. The process resulted in a small pH drop, and its relationship with conductivity was found. The nitrogen removal rate for the whole period oscillated around 1.5g N m(-2)d(-1) with a maximum value equal to 1.9 g N m(-2)d(-1). Parallel to the pilot plant experiment, a series of batch tests were run to investigate the influence on removal rates of different dissolved oxygen conditions and addition of nitrite. The highest nitrogen removal rate (5.2g N m(-2)2d(-1)) in batch tests was obtained when the Anammox process was stimulated by the addition of nitrite. In the simultaneous partial nitritation and Anammox process, the partial nitritation was the rate-limiting step.

Lysozyme expression by breast carcinomas, correlation with clinicopathologic parameters, and prognostic significance

BACKGROUND

Here we evaluate the expression and prognostic value of lysozyme, a milk protein that is also synthesized by a significant percentage of breast carcinomas, in women with breast cancer.

METHODS

Lysozyme expression was examined by immunohistochemical methods in a series of 177 breast cancer tissue sections. Staining was quantified by using the HSCORE system, which considers both the intensity and the percentage of cells staining at each intensity. The prognostic value of lysozyme was retrospectively evaluated by multivariate analysis that took into account conventional prognostic factors.

RESULTS

A total of 126 of 177 carcinomas (69.4%) stained positive for this protein, but there were clear differences among them with regard to the intensity and percentage of stained cells. Lysozyme values were higher in well-differentiated and moderately differentiated tumors than in poorly differentiated tumors (P < .05). Similarly, lysozyme levels were higher in small and node-negative tumors than in large and node-positive tumors (P < .05). Moreover, results indicated that low lysozyme content predicted shorter relapse-free survival and overall survival (P < .005). Separate Cox multivariate analysis in subgroups of patients as defined by node status showed that lysozyme expression was an independent prognostic factor able to predict both relapse-free survival and overall survival in node-negative patients (P < .05).

CONCLUSIONS

Tumoral expression of lysozyme is associated with lesions of favorable evolution in breast cancer. This milk protein may be a new prognostic factor in patients with breast cancer.

Allogeneic bone marrow transplantation vs chemotherapy for the treatment of childhood acute lymphoblastic leukaemia in second complete remission (revisited 10 years on)

In 1989 we carried out a trial comparing allogeneic BMT to chemotherapy (CT) in 76 children with relapsed acute lymphoblastic leukaemia (ALL). Ten years on we have clinically revised outcome to firmly establish the role of each treatment, to analyse the importance of length of first remission and to provide long-term actuarial results for disease-free survival (DFS) and relapse rate in each group. For 21 patients within the transplantation group, probability of DFS and relapse are 42.8 +/- 10.8% and 40.2 +/- 11.7% (s.e.), respectively. In the chemotherapy group, probability of DFS is 10.0 +/- 4.74% (P = 0.001) and probability of relapse 87.5 +/- 5.2% (P = 0.0004). These results strongly reflect those at initial analysis, confirming a key role of BMT in the management of ALL in second remission. Moreover, on univariate analysis only two factors influenced DFS: treatment group and length of first complete remission (less or more than 30 months from first CR). Thus, it seems clear that the best therapeutic option in early relapse is BMT, whereas DFS in late relapse is at the limit of significance (P = 0.07), with a higher relapse rate in the CT group. Although encouraging results using intensified rotational combination chemotherapy have been published, prospective randomised studies are needed to assess with certainty the best therapeutic option in these patients.

Individual Prognosis of Diabetes Long-term Risks: A CBR Approach

We present DIRAS, an application to support physicians in determining the risk of complications for individual diabetic patients. The risk pattern of each diabetic patient is obtained using a Case-based Reasoning method called LID. Case-based Reasoning is an Artificial Intelligence technique based on solving new situations according to past experiences. For each patient, the LID method determines the risk of each diabetic complication according to the risk of already diagnosed patients. In addition, LID builds a description that can be viewed as an explanation of the obtained risk.

Phosphorus release from ash, dried sludge and sludge residue from supercritical water oxidation by acid or base

Leaching of ash and dried sewage sludge were investigated and compared with the leaching results of sludge residue from supercritical water oxidation (SCWO). This article focuses on how the composition of ash and sludge residues influences the extraction of phosphate and heavy metals and if different treatment temperatures of the sludge effect the leachability. Results showed that acid leaching gave a higher release of phosphate than alkaline leaching for all ash and sludge residue samples. Also, alkaline leaching dissolved phosphate with a lower metal contamination than acid leaching. Furthermore, it was found that iron had a low release at both alkaline and acid leaching from ash and from SCWO residue. The difference in composition of ash and sludge residue samples had no significant influence on release of phosphate at high concentrations of acid. Phosphate release from ash, dried sludge at 300 degrees C and SCWO residue showed similar results at 1M acid leaching. However, it seems to be easier to release phosphate from the SCWO residue than from the ash at low acid concentrations. SCWO residue showed higher release than the other ashes at 0.5M HCl. Results for alkaline leaching showed higher release from ash at 1M NaOH than from SCWO residue or from dried sludge at 300 degrees C. The leaching of phosphate from dried sludge seems to be temperature dependent, as the dried sludge treated at higher temperature showed less release of phosphate. It was found that the pre-treatment of the ash may be important for better release of phosphate.

Evaluation of deammonification process performance at different aeration strategies

In a deammonification process applied in the moving bed biofilm reactor (MBBR) oxygen is a crucial parameter for the process performance and efficiency. The objective of this study was to investigate different aeration strategies, characterised by the ratio between non-aerated and aerated phase times (R) and dissolved oxygen concentrations (DO). The series of batch tests were conducted with variable DO concentrations (2, 3, 4 mg L(-1)) and R values (0-continuous aeration; 1/3, 1, 3-intermittent aeration) but with the same initial ammonium concentration, volume of the moving bed and temperature. It was found that the impact of DO on deammonification was dependent on the R value. At R=0 and R=1/3, an increase of DO caused a significant increase in nitrogen removal rate, whereas for R=1 and R=3 similar rates of the process were observed irrespectively of the DO. The highest nitrogen removal rate of 3.33 g N m(-2) d(-1) (efficiency equal to 69.5%) was obtained at R=1/3 and DO=4 mg L(-1). Significantly lower nitrogen removal rates (1.17-1.58 g N m(-2) d(-1)) were observed at R=1 and R=3 for each examined DO. It was a consequence reduced aerated phase duration times and lesser amounts of residual nitrite in non-aerated phases as compared to R=1/3.

Initial proximal obstruction of ventriculoperitoneal shunt in patients with preterm-related posthaemorrhagic hydrocephalus

BACKGROUND/AIMS

Obstruction is the most common complication of ventriculoperitoneal shunts in patients with hydrocephalus. Despite technical advances, rates of obstruction have barely decreased and remain at over 40% of cases. Patients suffering from preterm-related posthaemorrhagic hydrocephalus are considered a group with a particularly high risk of obstruction. The aim of the present study was to review our series of patients with preterm-related posthaemorrhagic hydrocephalus and analyse the occurrence of the first ventricular shunt obstruction as well as the related clinical and radiological factors.

METHODS

We conducted a retrospective review of 103 cases treated from 1982 to 2010. Descriptive analysis, raw and adjusted bivariate correlations and survival analysis were performed.

RESULTS

Over the course of the follow-up, 42 patients presented at least one episode of obstruction that required proximal revision. Medium-opening pressure valves were associated with a higher rate of obstruction compared to low-opening pressure valves; however, in our series this association became statistically significant only in patients with a weight of over 2,000 g at the time of surgery (odds ratio 6.75). The occurrence of previous infection and the development of late slit ventricle syndrome were also significantly associated with obstruction of the ventricular catheter (odds ratios 3.35 and 4.27, respectively).

CONCLUSIONS

Rates of shunt obstruction in preterm-related posthaemorrhagic hydrocephalus remain high but do not seem to be higher than in other groups of paediatric hydrocephalus. Prevention of infection and the use of the appropriate type of valve design can help to decrease the incidence of proximal shunt obstruction, which in turn could decrease the incidence of symptomatic slit ventricle syndromes.

Noise levels during cesarean delivery: a prospective observational study

BACKGROUND

Excessive noise has negative implications for both clinicians and patients. Emergency cesarean deliveries require rapid co-ordination and communication, possibly increasing noise pollution. We aimed to determine if noise levels in the Labor and Delivery operating room were higher during emergency cesarean deliveries than during non-emergency cesarean deliveries.

METHODS

We conducted a prospective observational study measuring noise levels in Labor and Delivery operating rooms at a single academic medical center. Sound meters placed on anesthesia machines and events charted in the electronic medical record were used to correlate noise levels to clinical activity. Noise levels in all cesarean deliveries were recorded for one year. Deliveries were classified into two groups: non-emergency (routine or urgent) and emergency. We compared noise levels of the groups at eight time points of interest: anesthesia provider enters operating room (T1), induction (T2), five minutes before incision (T3), three minutes before incision (T4), one minute before incision (T5), time of incision (T6), delivery (T7), and five minutes before initiating emergence (T8).

RESULTS

Noise levels were measured for 440 cesarean deliveries. Forty were classified emergency and 400 non-emergency (304 routine, 96 urgent) procedures. Emergency cesarean deliveries were noisier at all eight time points, although the absolute difference in decibels between the two groups was modest. The difference in noise level reached statistical significance at five time points (T1, T2, T5, T6, and T7).

CONCLUSION

Noise levels were higher during emergency than during non-emergency cesarean deliveries.

Hemopoietic stem cell transplantation in childhood: reduction in mortality and improvement of survival over the years

Stem cell transplantation (SCT) is an effective treatment for life-threatening hematologic and nonhematologic pediatric diseases. Reducing transplant-related mortality (TRM), a major complication of SCT, to improve long-term survival, therefore, is one of the main objectives of transplantation teams. We analyzed TRM and overall survival (OS) over the years in children undergoing SCT in our center. From June 1998 to October 2002, 156 consecutive children, 105 boys and 51 girls, median age 10 years (range, 2-18), with different diagnoses underwent SCT (100 autologous and 56 allogeneic). OS and TRM were analyzed in 2 different periods (June 1989-December 1998 and January 1999-October 2002) and grouped according to the different SCT modalities. The median follow-up was 18 months (range, 1-160). Autologous TRM showed a statistically significant improvement within 1999-2002 (0%) compared with 1989-1998 (12.2%) (P < .05). There were no statistical differences for allogeneic SCT. OS was 34% in the first period and 80.4% in the second period (P < .01), the improvement being for both autologous and allogeneic SCT. In our study, TRM decreased significantly for those children receiving autologous SCT in recent years. OS was significantly better in the latter period (1999-2002), both globally and for each SCT modality.

Nitrogen removal rates at a technical-scale pilot plant with the one-stage partial nitritation/Anammox process

Traditional nitrification/denitrification is not suitable for nitrogen removal when wastewater contains high concentrations of ammonium nitrogen and low concentrations of biodegradable carbon. Recently, a deammonification process was developed and proposed as a new technology for treatment of such streams. This process relies on a stable interaction between aerobic bacteria Nitrosomonas, that accomplish partial nitritation and anaerobic bacteria Planctomycetales, which conduct the Anammox reaction. Simultaneous performance of these two processes can lead to a complete autotrophic nitrogen removal in one single reactor. The experiments where nitrogen was removed in one reactor were performed at a technical-scale moving-bed pilot plant, filled with Kaldnes rings and supplied with supernatant after dewatering of digested sludge. It was found that a nitrogen removal rate obtained at the pilot plant was 1.9 g m(-2) d(-1). Parallel to the pilot plant run, a series of batch tests were carried out under anoxic and aerobic conditions. Within the batch tests, where the pilot plant's conditions were simulated, removal rates reached up to 3 g N m(-2)d(-1). Moreover, the batch tests with inhibition of Nitrosomonas showed that only the Anammox bacteria (not anoxic removal by Nitrosomonas) are responsible for nitrogen removal.

Model extension, calibration and validation of partial nitritation-anammox process in moving bed biofilm reactor (MBBR) for reject and mainstream wastewater

In the paper, the extension of mathematical model of partial nitritation-anammox process in a moving bed biofilm reactor (MBBR) is presented. The model was calibrated with a set of kinetic, stoichiometric and biofilm parameters, whose values were taken from the literature and batch tests. The model was validated with data obtained from: laboratory batch experiments, pilot-scale MBBR for a reject water deammonification operated at Himmerfjärden wastewater treatment and pilot-scale MBBR for mainstream wastewater deammonification at Hammarby Sjöstadsverk research facility, Sweden. Simulations were conducted in AQUASIM software. The proposed, extended model proved to be useful for simulating of partial nitritation/anammox process in biofilm reactor both for reject water and mainstream wastewater at variable substrate concentrations (influent total ammonium-nitrogen concentration of 530 ± 68; 45 ± 2.6 and 38 ± 3 gN/m³ - for reject water - and two cases of mainstream wastewater treatment, respectively), temperature (24 ± 2.8; 15 ± 1.1 and 18 ± 0.5°C), pH (7.8 ± 0.2; 7.3 ± 0.1 and 7.4 ± 0.1) and aeration patterns (continuous aeration and intermittent aeration with variable dissolved oxygen concentrations and length of aerated and anoxic phases). The model can be utilized for optimizing and testing different operational strategies of deammonification process in biofilm systems.

[A new case of congenital leukemia with leukemia cutis]

Congenital leukaemia is a condition occurring very rarely. In a recent review in 1993, 175 cases are reported, 25-30% of them being well documented as leukaemia cutis. We reported a new case of congenital leukaemia diagnosed as an acute non lymphoblastic leukaemia M4 (FAB) and diagnosed at birth. It involves a newborn female at 42 weeks of gestational age. The most relevant clinical features were hepatomegaly and cutaneous petechial lesions along with a generalized distribution of nodules. From the blood peripheral count, leukocytosis is observed (177 x 10(9)/L) with 48% blasts of myeloid immunophenotype. The coagulation studies were consistent with a disseminated intravascular coagulation syndrome. A biopsy carried out on a cutaneous nodule, revealed diffuse dermoepidermic infiltration by immature cells of myeloid lineage, with cellularity and count similar to that of bone marrow and peripheral blood. The karyotype in the peripheral blood was normal. Infectious and immune causes were excluded as well as constitutional illnesses associated with unstable haematopoiesis. The family rejected treatment with chemotherapy and the baby died on day 53 of life due to progressive leukocytosis and concurrent infection. Our case, like 80% of the cases reported, is of myeloid origin and confirms the fatal evolution of untreated congenital leukaemia.

Regional planning and product recovery as tools for sustainable sludge management

The article presents two aspects of sludge management: regional planning and product recovery. The introduction of these two elements can reduce the cost, close the ecocycle and make the management more sustainable. A spreadsheet program to optimize the regional location of different facilities is presented. The simple example shows the potential of the model. The brief comparison of formal problems concerning sludge disposal in Poland and Sweden is also discussed. Requirements of phosphorus recovery and recycling of phosphorus to the phosphate industry make sludge fractionation in combination with product recovery a new development in wastewater handling. Phosphorus recovery from sludges with chemical bound phosphorus requires complex and expensive process technology and may therefore lead to increased regional sludge management with a central sludge treatment plant.

Individual prognosis of diabetes long-term risks: a CBR approach

We present DIRAS, an application to support physicians in determining the risk of complications for individual diabetic patients. The risk pattern of each diabetic patient is obtained using a Case-based Reasoning method called LID. Case-based Reasoning is an Artificial Intelligence technique based on solving new situations according to past experiences. For each patient, the LID method determines the risk of each diabetic complication according to the risk of already diagnosed patients. In addition, LID builds a description that can be viewed as an explanation of the obtained risk.

Impact of seeding with nitrifying bacteria on nitrification process efficiency

Seeding of nitrifying bacteria into the activated sludge process was studied both theoretically and experimentally. A simple model was developed for prediction of the effects of seeding of nitrifying bacteria from a separate stage into the activated sludge process. The purpose of seeding is to improve the treatment results and the process stability as well as to decrease the volume requirements of the process. Pilot plant studies were carried out at the Uppsala municipal wastewater treatment plant in order to evaluate the effects of seeding. One line was supplied with supernatant from dewatering of digested sludge and the nitrification process gave an activated sludge with a high fraction of nitrifying bacteria, suitable for seeding. The other line was supplied with pre-precipitated wastewater and with the excess sludge from the line treating the supernatant. The experimental results showed that nitrification could be obtained at sludge ages that would otherwise preclude nitrification. Performance relationships for the system developed, based on laboratory and on-line measurements were studied and are presented. The studies show that seeding may decrease the necessary volume needs for a stable nitrification process and that the effects could be predicted by use of a simple model.

Generation of LAK cells in vitro in patients with acute leukemia

The in vitro stimulation of lymphocytes with interleukin-2 (IL-2) generates lymphokine-activated killer (LAK) cells with tumoricidal potential. In this work we studied the cytolytic capacity of LAK cells in 51 acute leukemia patients in complete remission (CR) after chemotherapy (CT), in 24 acute leukemia patients who had undergone autologous bone marrow transplantation (ABMT), and in a control group of 44 normal donors. In the normal donor control group the effect of non-IL-2-activated peripheral blood mononuclear cells (PBMC) against blast cells was always lower than 10% lysis, which we have taken as a lower limit for positive results. In 95% of post-CT patients, the lytic effect of PBMC was negative. LAK cells produced positive results in 82% of normal donors and in 37.5% of post-CT patients. The effect of PBMC against K562, i.e. natural killer (NK) activity, in post-CT patients as well as in post-ABMT patients was reduced in comparison with the average for normal donors. LAK cells from 25% of post-CT patients had no notable activity against K562 or Raji, nor was there any positive effect against autologous blast cells. In the rest (75%), one-half generated positive activity. We did not observe any correlation between lytic activity in PBMCs or in LAK cells, nor did we observe significant differences between lytic activity in patients with acute lymphoblastic leukemia (ALL) and those with acute myeloblastic leukemia (AML), or between patients who had undergone CT and those receiving ABMTs. These results support the use of IL-2 as a treatment against minimal residual leukemia.