Nitrification activity in the presence of 2-chlorophenol using whole nitrifying cells and cell-free extracts: batch and SBR assays.

Kinetic assays with a nitrifying consortium with whole nitrifying cells amended with 5 mg 2-CP-C/L and 100, 200, 300, or 500 mg NH4+-N/L were carried out in batch and nitrifying sequencing batch reactor (SBR) cultures. No nitrification activity was observed in batch assays with 100 mg NH4+-N/L and 5 mg 2-CP-C/L. Nevertheless, increasing the ammonium concentration from 200 to 500 mg NH4+-N/L allowed simultaneous ammonium and nitrite oxidation even in the presence of 5 mg 2-CP-C/L plus the halogenated compound consumption. Under these conditions, the ammonium monooxygenase enzyme participated in 2-CP consumption. Complete nitrification and simultaneous elimination of 5 mg 2-CP-C/L were achieved in the SBR amended with 200-500 mg NH4+-N/L. The inhibitory effect of 2-CP on the nitrite oxidation process completely disappeared under these conditions. Assays with nitrifying cell-free extracts, ammonium (100 mg NH4+-N/L), and 2-CP (5 mg 2-CP-C/L) were also conducted. In the absence of 2-CP, the nitrifying cell-free extracts maintained up to 60% of the nitrifying activity compared to whole-cells. Contrary to whole-cell assays, cell-free extracts were capable of simultaneously oxidizing ammonium and consuming 2-CP. However, the inhibitory effect of 2-CP on nitrification was still present as lower specific rates of ammonium consumption and nitrate production were obtained. Thus, these assays indicate that the presence of 2-CP affects both, the ammonium transport mechanism and the activity of nitrifying enzymes. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03764-z.

New technique for nephron-sparing surgery in polar tumours. A modification of the Kim technique. / Nueva técnica para cirugía conservadora de nefronas en tumores polares. Una modificación de la técnica de Kim.

INTRODUCTION AND OBJECTIVES: Nephron-sparing surgery (NSS) is the indication, provided it is feasible and meets the international treatment guidelines. One of the objectives of performing NSS is to reduce the ischemia time as much as possible. We propose a surgical technique for treating polar renal tumours and those larger than 4cm based on the principle of the technique described by Kim in 1964. METHOD: The technique performs a continuous circular suture on the base of the tumour, achieving compression of the renal pole without vascular clamping, facilitating haemostasis and avoiding the blind transfixion performed in Kim's original technique. We selected 28 patients for the implementation of the technique. RESULTS: The patients' mean age was 56 years (30-69). The R.E.N.A.L. scores were as follows: 12 of low complexity, 12 of moderate complexity and 4 of high complexity. The mean surgical time was 109minutes (75-140), and the mean estimated blood loss was 120mL (50-300mL). No positive margins were identified, and no patients required blood transfusions. The mean stay was 3.7 days (2-6). There were no Clavien grade 2 or higher complications. There were 3 Clavien 1 complications (fever). The difference in glomerular filtration rate was -0.71mL/min/m2. The pathology was malignant in 26 cases, 19 of them clear-cell carcinomas. Two cases were reported as oncocytomas. CONCLUSION: The proposed technique showed acceptable results, with a low rate of complications in the patient group.

Effect of sulfate and lactate loading rates on the respiration process and microbial population changes measured by ecological indices.

In a sulfate reducing process, increasing loading rates and sulfide accumulation may induce population changes resulting in decreasing effectiveness of the process. Thus, the relationship between microbial metabolism changes and population dynamics was studied. An upflow anaerobic sludge blanket reactor was operated at different sulfate loading rates (SLR), from 290 to 981 mg SO4-S/L d at a constant carbon/sulfur ratio of 0.75. When the SLR was increased, the total organic carbon and sulfate consumption efficiencies decreased to nearly 30% and 25%, respectively. The acetate and propionate yields increased with increasing SLR and 385±7 mg sulfide-S/L d was reached. The ecological indices, determined by random amplified polymorphic DNA and denaturing gradient gel electrophoresis techniques, diversity and evenness were found to be constant, and similarity coefficient values remained higher than 76%. The results suggest that the microbial population changes were negligible compared with metabolic changes when SLR was increased. The sulfide accumulation did not modify the microbial diversity. The sequencing of 16S rRNA genes showed strains related to sulfate reducing, fermentation, and methanogenesis processes. The results indicated that the decreasing of effectiveness, under the experimental conditions tested, was dependent more on operational parameters than microbial changes.

Kinetic and physiological evaluation of ammonium and nitrite oxidation processes in presence of 2-chlorophenol.

The effect of 2-chlorophenol (2-CP) on ammonium and nitrite-oxidizing processes was kinetically evaluated in batch cultures with nitrifying sludge at steady state. Assays with ammonium or nitrite as energy source and 2.5, 5.0, or 10.0 mg 2-CP-C/l were conducted. Control assays without 2-CP were also performed. Ammonium-oxidizing activity was completely inhibited at the different 2-CP concentrations, whereas nitrite-oxidizing activity was present as nitrite was completely consumed and converted to nitrate irrespectively of 2-CP concentration. In the presence of 2.5 and 5.0 mg 2-CP-C/l, no significant effect on specific rates of nitrite consumption and nitrate production was observed, but a significant decrease on these parameters was observed at 10.0 mg 2-CP-C/l. The nitrifying sludge previously exposed to 2-CP was unable to completely recover its ammonium and nitrite oxidation capacity. Nevertheless, complete 2-CP consumption was achieved in all assays. The effect of 2-CP on ammonium oxidation was observed at kinetic and metabolic pathway level, whereas the effect on nitrite oxidation was observed only at kinetic level. The results obtained in this work evidenced that in order to achieve a successful nitrification process the presence in wastewater of even 2.5 mg 2-CP-C/l should be avoided.

Intraoperative hepatic artery blood flow predicts early hepatic artery thrombosis after liver transplantation.

Hepatic artery complications after orthotopic liver transplantation are associated with a high rate of graft loss and mortality (23% to 35%) because they can lead to liver ischemia. The reported incidence of hepatic artery thrombosis (HAT) after adult liver transplantation is 2.5% to 6.8%. Typically, these patients are treated with urgent surgical revascularization or emergent liver retransplantation. Since January 2007, we have recorded the postanastomotic hepatic artery flow after revascularization. The aim of this study was to assess the relationship between hepatic blood flow on revascularization and early HAT. Retrospectively, we reviewed perioperative variables from 110 consecutive liver transplantation performed at the Virgen del Rocío University Hospital (Seville, Spain) between January 2007 and October 2010. We evaluated the following preoperative (donor and recipient) and intraoperative variables: donor and recipient age, cytomegalovirus serology, ABO-compatibility, anatomical variations of the donor hepatic artery, number of arterial anastomoses, portal and hepatic artery flow before closure, cold ischemia time, and blood transfusion. These variables were included in a univariate analysis. Of the 110 patients included in the study, 85 (77.7%) were male. The median age was 52 years. ABO blood groups were identical between donor and recipient in all the patients. The prevalence of early HAT was 6.36% (7 of 110). Crude mortality with/without HAT was 22% versus 2% (P = .001), respectively. Crude graft loss rate with/without HAT was 27% versus 4% (P = .003), respectively. Early HAT was shown to be primarily associated with intraoperative hepatic artery blood flow (93.3 mL/min recipients with HAT versus 187.7 mL/min recipients without HAT, P < .0001). No retransplantation showed early HAT. In our experience, intraoperative hepatic artery blood flow predicts early HAT after liver transplantation.

p-Cresol biotransformation by a nitrifying consortium.

The oxidizing ability of a nitrifying consortium exposed to p-cresol (25 mg CL(-1)) was evaluated in batch cultures. Biotransformation of the phenolic compound was investigated by identifying the different intermediates formed. p-Cresol inhibited the ammonia-oxidizing process with a decrease of 83% in the specific rate of ammonium consumption. After 48 h, ammonium consumption efficiency was 96+/-9% while nitrate yield reached 0.95+/-0.06 g NO(3)(-)-Ng(-1)NH(4)(+)-N consumed. High value for nitrate production yield showed that the nitrifying metabolic pathway was only affected at the specific rate level being nitrate the main end product. The consortium was able to totally oxidize p-cresol at a specific rate of 0.17+/-0.06 mg p-cresol-Cmg(-1) microbial protein h(-1). p-Cresol was first transformed to p-hydroxybenzaldehyde and p-hydroxybenzoate, which were later completely mineralized. In the presence of allylthiourea, a specific inhibitor of ammonia monooxygenase (AMO), p-cresol was oxidized to the same intermediates and in a similar pattern as obtained without the AMO inhibitor. AMO seemed not to be involved in the p-cresol oxidation process. When p-hydroxybenzaldehyde was added (25 mg CL(-1)), the nitrifying process was inhibited in the same way as observed with p-cresol, indicating that p-hydroxybenzaldehyde could be the main compound responsible for nitrification inhibition. p-Hydroxybenzaldehyde was accumulated during 15 h before complete consumption at a specific rate value eight times lower than the p-cresol consumption rate. Results showed that p-hydroxybenzaldehyde oxidation was the limiting step in p-cresol mineralization by the nitrifying consortium.

Application of the McCluskey Index to predict blood product requirements during liver transplantation.

BACKGROUND: A recent study proposed a risk index (McCluskey index) based on 7 parameters to identify the transfusion needs of patients during surgery and in the first 24 hours postoperation. The initial objective of our study was to validate this predictor for blood product transfusions. PATIENTS AND METHODS: We undertook a retrospective, observational study of all liver transplant patients between January 1, 2005 and December 31, 2006. The following variables were recorded for each patient: age, gender, patient comorbidity, biochemical values prior to liver transplantation, and transfusion needs. RESULTS: Comparing the transfusion needs of those patients with scores <5 with those of scores >/=5, we observed significant differences in terms of the use of red blood cell concentrates, plasma, and platelets, both during the first 24 hours and in the total number. The index sensitivity was 80% (95% confidence interval [CI]: 71.23-88.76), with a specificity of 84.21% (95% CI: 67.81-100), where the positive predictive value was 95.52% (95% CI: 90.57-100.4) and the negative predictive value was 50% (95% CI: 32.67-67.32). CONCLUSION: The McCluskey index showed sufficient sensitivity and specificity to predict which patients will require a massive transfusion.

[Prospective evaluation of fracture risk in osteoporotic patients after low cement volume vertebroplasty]. / Suivi prospectif du risque fracturaire après vertébroplastie utilisant un faible volume de ciment chez des patients ostéoporotiques.

PURPOSE: To prospectively compare the incidence of new fractures (as demonstrated on MR) within the first 3 months after an initial fracture in a population treated with low cement volume vertebroplasty and a population treated conservatively. MATERIALS AND METHODS: From 49 patients admitted for osteoporotic vertebral compression fracture, 22 underwent CT guided vertebroplasty with injection of 1-3 ml of PMMA, and 27 were treated conservatively. All patients underwent MR at presentation and at 3 months to detect new compression fractures. RESULTS: Twelve patients (54%) treated with vertebroplasty showed new fractures at 3 months compared to 10 (37%) in the control group. This was not statistically different (p=0.049). In the vertebroplasty group, the new fractures involved vertebrae adjacent to the treated vertebra in 77% of cases (p=0.009) compared to only 15% in the control group. During the 3-month period, 3 patients, including 2 treated with vertebroplasty, required hospital admission due to fracture related acute lumbar back pain. CONCLUSION: The small amount of injected cement does not prevent fractures of adjacent vertebrae but does reduce the extravasation of PMMA in adjacent tissues.

[Retinal angiomatous proliferation not associated with age-related macular degeneration. Favourable outcome after photodynamic therapy]. / Proliferación angiomatosa retiniana no relacionada con degeneración macular asociada a la edad. Buena respuesta al tratamiento con terapia fotodinámica.

CASE: A 55-year-old male was diagnosed with exudative-hemorrhagic maculopathy, with no signs observed of drusen or pigmentary epithelium defects suggestive of age-related macular degeneration (ARMD). Fluorescein angiography (FA) and indocyanine green choroidal angiography (ICGA) showed retinal angiomatous proliferation (RAP). Afferent arteriole and retinal drainage venule connection was also observed. Treatment with a single Photodynamic Therapy provided an optimal outcome. DISCUSSION: RAP is a form of neovascular ARMD described in recent years; it consists of an angiomatous proliferation that originates from the retinal capillary system and extends posteriorly into the subretinal space. Our patient showed typical RAP findings without any sign of ARMD

Vascular emergencies in liver trauma.

The use of CT in the diagnosis and management of liver trauma is responsible for the shift from routine surgical versus non-surgical treatment in the management of traumatic liver injuries, even when they are of high grade. The main cause of complication and of death in liver trauma is related to vascular injury. The goal of this review focussed on the vascular complications of liver trauma is to describe the elementary lesions shown by CT in liver trauma including laceration, parenchymal hematoma and contusions, partial devascularisation, subcapsular hematomas, hemoperitoneum, active bleeding, pseudoaneurysm of the hepatic artery, bile leak, and periportal oedema, to illustrate the possible pitfalls in CT diagnosis of liver trauma and to underline the key-points which may absolutely be present in a CT report of liver trauma. Then we will remind the grading system based on the CT features and we will analyze the interest and limitations of such grading systems. Last we will discuss the diagnostic strategy at the early phase in patients with suspected liver trauma according to their clinical conditions and underline the conditions of arterial embolization, and then we will discuss the diagnosis strategy at the delayed phase according to the suspected complications.

[Imaging of traumatic injuries of the knee]. / Imagerie des traumatismes du genou.

Traumatic injuries to the knee are frequent (road or sports related accidents, falls in elderly people). The Ottawa knee rules are applied and dictate the need for additional evaluation. Some fractures are adequately assessed on plain radiographs alone whereas other fractures (tibial plateau fracture) require additional evaluation with CT. Some fractures may be occult: the significance of lipohemarthrosis (indirect sign of intra-articular fracture on the lateral radiograph with horizontal beam) must be known. Benign appearing avulsion fractures suggest the presence of underlying capsuloligamentous injuries requiring further evaluation with MRI. The imaging work-up of sprains is usually negative. MRI may show areas of bone contusion that further the understanding of the mechanism of injury, predict and confirm the presence of capsuloligamentous injuries. Angiography is performed to detect popliteal artery injuries after knee dislocation which is associated with a risk of ischemia.

[Optical coherence tomography of retinal pigment epithelial tears]. / Optical coherence tomography en desgarro del epitelio pigmentario retiniano.

CASE REPORTS: Three cases of pigmentary epithelial tears are described in this study. One of them was related to previous extrafoveal photocoagulation, whereas the other two were idiopathic. Fluorescein angiography (FA) and optical coherence tomography (OCT) were performed to confirm the clinical diagnosis. DISCUSSION: Few studies using OCT to assess pigmentary retinal epithelial (RPE) tears have been published in the world literature. The main findings of our study included hyper-reflectant line breaks, choroidal hyper-reflectance due to the lack of RPE and RPE double layering where it was folded. Images were frequently associated with RPE tears and neurosensorial retinal detachment.

Toluene mineralization by denitrification in an up flow anaerobic sludge blanket (UASB) reactor.

In order to examine the effect of easily degradable substrate such as acetate on toluene mineralization by denitrification, an upflow anaerobic sludge blanket (UASB) reactor in steady state was set up. The experimentation was carried out in two stages. Initially, the reactor was fed with a carbon loading rate of 250 mg acetate-C L-1 d-1 as electron source. Nitrate loading rate (mg ) was adjusted to obtain a constant C/N ratio of 1.4. In the second stage, five toluene-C loading rates (TLR, mg toluene-C L-1 d-1), 25, 50, 75, 100 and 125, were assessed while total carbon loading rate and C/N were maintained constant at 250 mg C L-1 d-1 and 1.4, respectively. In so doing, acetate-C loading rate (mg acetate-C L-1 d-1) was gradually substituted by toluene-C. When acetate-C was the only electron source a dissimilative denitrifying process resulted as indicated by bicarbonate yield YHCO3, mg produced/mg carbon consumed) of 0.74 +/- 0.005 and denitrifying yield (YN2, mg N2 produced/mg consumed) of 0.89 +/- 0.042. The addition of different TLR did not affect the biological process as consumption carbon efficiency (CCE) values remained up to 95% +/- 3.5 and YHCO3 and YN2 values were higher than 0.71 +/- 0.03 and 0.88 +/- 0.01, respectively. Toluene mineralization by denitrification in continuous culture was successfully achieved. A simple UASB denitrifying reactor system has promising applications for complete conversion of nitrate, toluene and acetate into N2 and CO2 with a minimal sludge production.

Scoring guide when deciding to accept an organ for a liver transplant.

UNLABELLED: Our objective was establish a scoring system that allows a donor to be evaluated quickly and easily using a set of variables that are evaluated prior to the donation and another set that are evaluated during surgery. MATERIALS AND METHODS: Prior to the donation we analyzed age, medication requirements, natremia, hepatic biochemistry, gas levels, days in ICU, history of hypertension, and weight. A value of 40% was allocated to this group of factors. During the transplant we assessed the characteristics of the organ-shine, consistency, surface, edge, color, presence of steatosis, and atheromatosis. A value of 60% was allocated to this set. We established a scale of 1 to 10, only accepting organs scoring 5 or more points. Those grafts that received a score between 5 and 7.5 points were called suboptimal and those with over 7.5 points, optimal. We prospectively analyzed 133 donors whose organs were implanted. RESULTS: The survival rate at 1 year was 85%, and the rejection rate was 12%. The incidence of primary graft dysfunction was 8.2% (n = 11) and that of primary graft nonfunction 2.2% (n = 3). The incidence of primary graft dysfunction was greater within the group with fewer points (suboptimal). There were no differences between the optimal and suboptimal groups in terms of primary malfunction, survival, or rejection rate. CONCLUSIONS: The score provided a guide to decide whether to accept viable organs for implantation, given that the point system was obtained quickly and easily. When greater than 5, it correlated with low rates of primary nonfunction (<3%) and of primary graft dysfunction (<15%), with acceptable survival at 1 year (>80%) and acute rejections rate (<15%).

[Imaging of the diabetic foot]. / Imagerie ostéo-articulaire du pied diabétique.

Destruction in diabetic feet is secondary to neuropathy (peripheral and autonomic nervous system) in association with microangiopathy. The loss of sensation to pain and the static trouble lead to increase the pressure in some areas and predispose to pedal skin ulceration, the precursor of osteomyelitis. Plain radiography should be the first step in the evaluation for diagnosis and follow-up. The initial patterns are nonspecific but very rapid evolution associating osteolysis, osteosclerosis and fragmentation lead to the Charcot foot. When osteomyelitis is suspected, scintigraphy with labelled white blood cells and MRI are necessary to differentiate infection from neuropathy.

[Pseudophakic cystoid macular edema. Assessment with optical coherence tomography]. / Edema macular quístico pseudofáquico. Detección mediante "optical coherence tomography".

PURPOSE: To determine the incidence of cystoid macular edema (CME) by means of clinical evaluation and subclinical assessment by means of ocular coherence tomography (OCT), and to compare the incidence between diabetic and non-diabetic groups of patients. METHODS: Prospective study of 260 consecutive cataract surgeries operated from September 2004 to March 2005. The procedures were performed by means of phacoemulsification plus intraocular acrylic lens implantation. Group A: 208 eyes of non-diabetic patients; Group B: 42 eyes of patients with diabetes and Group C: 10 eyes of diabetic patients with macular edema that received an intravitreal injection of triamcinolone at the end of surgery. Postoperative follow-up visits were performed 6 days (basal visit), 5 weeks and 12 weeks after surgery. Each visit included posterior pole biomicroscopy and OCT. RESULTS: Central macular thickness measured by OCT was significantly increased in group B compared with group A (241.6 versus 204.6 microm; p<0.001). No clinical evidence of CME was found in group A, although 4 eyes (1.92%) showed macular thickness equal to or greater than 43.74 microm (2 standard deviations of the basal value for group A). In group B, clinical evidence of CME was found in 6 eyes, with decreased visual acuities (14.2%). The differences between these groups were statistically significant (p<0.001). The 10 eyes that received an intravitreal injection of triamcinolone after the surgical procedure showed a mean decrease in central retinal thickness of 77 microm after 12 weeks postoperative. CONCLUSIONS: This study has shown a low incidence of clinical CME. OCT showed increased macular thickness in both groups of patients in a small percentage of cases, and significantly increased macular thickness in diabetic patients.

Denitrification in presence of benzene, toluene, and m-xylene: kinetics, mass balance, and yields.

Denitrification of the electron donors toluene-C (15-100 mg/L), m-xylene-C (15-70 mg/L), benzene-C (5-25 mg/L), and acetate-C as experimental reference (50-140 mg/L) was carried out in batch culture. An initial concentration of 1.1 +/- 0.15 g of volatile suspended solids/L of denitrifying sludge without previous exposure to aromatic compounds was used as inoculum. The results showed toluene and nitrate consumption efficiency (ET and EN, respectively) of 100%. Toluene was completely mineralized (oxidized) to CO2. In all cases, the N2 (YN2) and HCO3-yields (YHCO3) were 0.97 +/- 0.01 and 0.8 +/- 0.05, respectively. The consumption efficiency (EX) of m-xylene (53 +/- 5.7%) was partial. The YN2 and YHCO3 were 0.96 +/- 0.01 and 0.86 +/- 0.02, respectively. Benzene was not consumed under denitrifying conditions. The specific consumption rates of toluene (qT) and m-xylene (qX) were lower than that of acetate (qA). The differences in specific consumption rates were probably owing to the negative effect of benzene, toluene, and isomers of xylene on the cell membrane.

[Idiopathic polypoidal choroidal vasculopathy]. / Vasculopatía coroidea polipoidal idiopática.

PURPOSE: To evaluate the incidence, clinical features and evolution of polypoidal choroidal vasculopathy (PCV) in our population. METHODS: Retrospective study of patients diagnosed with exudative and/or hemorrhagic maculopathy including age-related macular degeneration in the last two years and who have undergone a complete ophthalmologic exploration and videoangiography with fluorescein and indocyanine green. RESULTS: 250 patients were included in the study, 8 patients (3.2%) had clinical and angiographic criteria of PCV. The mean age was 68 years-old, 62.5% were men and 85.7% were caucasian. Ninety percent of cases presented clinically as a predominantly hemorrhagic macular detachment. The initial clinical diagnosis before indocyanine green angiography was exudative age-related macular degeneration in 90% of cases. The mean visual acuity was 0.2 at baseline and after follow-up. Laser treatment was performed in 4 eyes, achieving good anatomic and visual acuity results in 2 of them; both eyes of one patient were treated by photodynamic therapy with poor angiographic and functional outcome. CONCLUSIONS: Polypoidal choroidal vasculopathy is a clinical entity which is relatively frequent among patients previously diagnosed with exudative maculopathy. Indocyanine green angiography increases the number of correct diagnoses. Treatment must be individualized depending on the location of the lesions and the severity of the disease.

[Serpiginous choroiditis: clinical course and treatment]. / Coroiditis serpiginosa: evolución clínica y tratamiento.

PURPOSE: To evaluate the clinical evolution and treatment of serpiginous choroiditis in 11 diagnosed patients. METHODS: Retrospective study of 11 cases diagnosed with serpiginous choroiditis in our area, from 1980 to the present. We analyzed age at onset of symptoms, systemic diseases, ophthalmological symptoms at presentation, the location of lesions, initial and final visual acuity, recurrences, treatment régime and development of subretinal neovascularization. A complete ophthalmological examination and fluorescein angiograms were performed in all of them. RESULTS: The mean period of follow-up was 4 years. Average age was 56 years, predominantly in men (10/1). Five patients had known ischemic cardiopathy and systemic hypertension, one patient underwent a kidney transplant. All of them were treated with oral prednisone (1-1.5 mg/kg/daily) in the active stages. Three patients received triple therapy (prednisone, cyclosporine and azathioprine) that did not prevent the recurrences. Five patients developed a subretinal neovascularization, bilateral in three of them. CONCLUSIONS: The serpiginous choroiditis is a rare entity and the visual outcome prognosis is determined by the macular involvement. Men are predominantly affected in our series and corticosteroid treatment is effective in acute inflammatory episodes. Recurrences could not be prevented by triple therapy with immunosuppressive agents in our three patients.