Denitrification in presence of acetate and glucose for bioremediation of nitrate-contaminated groundwater.

With the current increasing interest in aquifer denitrification, recent attention has been given to cost-effective in-situ treatments such as Enhanced In-Situ Biological Denitrification (EISBD), which intends to stimulate the indigenous bacterial activity by injecting an external organic substrate and/or nutrients to the aquifer matrix. Within this context, laboratory batch assays have been conducted to develop a strategy for in-situ denitrification of a nitrate-contaminated aquifer in Argentona, Catalonia (Spain). The assays were run under aerobic and anaerobic conditions at a temperature of 17 degrees C to better simulate the conditions of the aquifer. Acetate and glucose were added to assess their potential to promote heterotrophic denitrifying bacteria activity. Overall, the results revealed that indigenous micro-organisms had the potential of reducing nitrate under appropriate conditions. Nitrate removal was complete and faster under anaerobic conditions, though high nitrate removals were also attained under initial aerobic conditions when a readily organic compound was amended at a sufficient dosage. The results also revealed that a significant amount of the available organic carbon was consumed by processes other than denitrification, namely aerobic oxidation and other microbial oxidation processes. To sum up, the results of this study demonstrated that addition of organic compounds into the groundwater is a promising method for in-situ bioremediation of nitrate in the Argentona aquifer. This approach could potentially be applied to a number of situations in which nitrate concentration is elevated and where indigenous micro-organisms with potential to reduce nitrate are present within the aquifer material.

Urinary tract infection's etiopathogenic role in nephrolithiasis formation.

Urolithiasis has a high prevalence and recurrence rate, especially in developed countries, and is a major public health issue with a high socioeconomic cost. There are multiple causes of urolithiasis, including urinary tract infection (UTI). Infection stones (mainly composed of struvite) are associated with renal infections by urease-producing bacteria. However, there is limited knowledge about the role of UTIs in the formation of stones that are apparently not related with infection. We hypothesize that UTIs promote the formation of certain urolithiasis that appear to be non-infection stones. Some recent studies have reported the presence of bacterial growth in cultures of stones removed by endourological procedures. These findings have led to the hypothesis that UTIs have a role in the formation of stones that are apparently non-infection stones. It is unknown whether these UTIs promoted stone formation, or if the stones became infected after formation. Several in vitro studies and ultrastructural microscopic analyses of urolithiasis are consistent with our hypothesis. If our hypothesis is correct, it could have a great impact on the treatment of urolithiasis. Especially, early identification and treatment of renal infections could help to prevent septic events, which are frequently life-threatening. It could also help to reduce the recurrence of urolithiasis, and thereby reduce health care costs. In conclusion, some evidence suggests that UTIs have a role in the formation of some apparently non-infection urolithiasis. If this is so, it could have a great impact on the treatment and prevention of this disease.

Distinct but redundant expression of the Frizzled Wnt receptor genes at signaling centers of the developing mouse brain.

The establishment of the regional subdivisions of the vertebrate CNS is accomplished through the activity of different neuroepithelial organizing centers. The wingless/int (Wnt) family of secreted glycoproteins, among other factors, plays a crucial role in signaling from these centers. Wnt1 secreted from the boundary between the mid- and hindbrain, for instance, controls the development of this brain region and of associated neuronal populations. Different Wnts secreted from the caudomedial pallium, the cortical hem, pattern the adjacent hippocampal field. The first step in Wnt signal transduction is binding of the Wnt ligand to its receptors, the seven-pass transmembrane Frizzled proteins. Inactivation of different Frizzled genes in mice have revealed an extensive functional redundancy between these receptors. In order to discriminate between a possible participation of different Frizzled receptors in the transduction of Wnt signals at the mid-/hindbrain boundary and the cortical hem, we have performed a detailed expression study of the 10 known murine Frizzled genes at crucial stages of mouse embryonic development. Our analysis reveals a highly dynamic yet distinct expression pattern of individual Frizzled genes in the anterior neural tube of the developing mouse embryo. The overlapping spatio-temporal expression of at least two and up to six Frizzled genes in any region of the developing mouse brain, however, also suggests a vast functional redundancy of the murine Frizzled receptors. This redundancy has to be taken into consideration for future analyses of Frizzled receptor function at these signaling centers in the mouse.

[Evaluation of the fine needle aspiration biopsy in the presurgical diagnosis of tumors of the parotid gland]. / Evaluación de la punción-aspiración con aguja fina (PAAF) como prueba prequirúrgica en las tumoraciones de glándula parótida.

The treatment ofparotid masses is generally surgery. The presurgical assesment is made by clinical examination, radiology and fine needle aspiration (FNA). FNA has been applied for the last decades and has been the subject of many reviews. It is a safe, rapid and economic procedure that can be made as an ambulatory procedure. In this study we have reviewed the parotidectomies performed in our institution during the years 1998 - 2003 where a preoperative FNA was available. The sensitivity of FNA in our hands is 40% and specifity 96.3%. We have also calculated the utility of clinical examination and radiology in the assessment of parotid masses.

[Surgical treatment of exostosis in the external auditory canal]. / Tratamiento quirúrgico de las exóstosis de conducto auditivo externo.

Exostoses of the external auditory canal are benign bony tumours very common in individuals who frequently participate in aquatic activities. Although most of the cases are asymptomatic, patients with more severe exostoses have recurrent episodes of external otitis and related conductive hearing loss. In the great majority of these cases, a medical treatment (aspiration and antibiotic drops) resolves the symptoms. Patients with more severe canal stenosis, resistant to medical treatment, are candidates for surgical removal of the exostoses. This report reviews our surgical experience with 45 patients, 52 ears, who have undergone surgical removal of exostoses in our Institution during the last 13 years. We describe the technique that we use a well as the results that we achieve.

Dscr1, a novel endogenous inhibitor of calcineurin signaling, is expressed in the primitive ventricle of the heart and during neurogenesis.

We have demonstrated that DSCR1 acts as a negative regulator of calcineurin-mediated signaling and that its transcript is overexpressed in the Down syndrome (DS) fetal brain. To evaluate the possible involvement of DSCR1 in DS, we have cloned the mouse gene and analyzed its expression pattern in the central nervous system (CNS). Early expression of Dscr1 is detected mainly in the heart tube and in the CNS in rhombomere 4 and the pretectum. From embryonic day 14.5 onwards, Dscr1 is widely distributed in the CNS but becomes more restricted as the brain matures. We confirmed its neuronal expression pattern in the adult, preferentially in Purkinje and pyramidal cells, by double labeling with glial fibrillary acidic protein. We also show that although Dscr1 is present in trisomy in the Ts65Dn mouse, the adult brain expression pattern is not significantly altered. This expression pattern indicated that Dscr1 is a developmentally regulated gene involved in neurogenesis and cardiogenesis and suggests that it may contribute to the alterations observed in these organ systems in DS patients.

[Immunohistochemistry study of EGFR expression in head and neck squamous cell carcinoma]. / Estudio por inmunohistoquímica de la expresión de EGFR en carcinoma de células escamosas de cabeza y cuello.

EGFR is an important transmembrane receptor member of the family of tyrosine kinases, that translates signals from both outside and inside the cell and plays a key role in numerous proceses that affect tumour development, growth, progresion, differentiation, inhibition of apoptosis and metastasis. Immunohistochemistry studies have shown that 40-80% of head and neck squamous cell carcinomas express EGFR and it has been suggested as a potential independent prognostic parameter. The objective of this study is to evaluate by immunohistochemistry the expresi6n of EGFR in a series of Head and Neck Squamous Cell Carcinoma and correlate it to clinico-pathological features and prognostic significance. We investigated expression of EGFR in 44 samples. There was a high expression in 41% of the cases. Even if we have not found that the expression of EGFR correlated with the prognosis of these patients the presence of EGFR is very important because there are chemical agents or drugs that can inhibit its activity.

Integration of 30 CA-repeat markers into the cytogenetic, genetic and YAC maps of human chromosome 21.

The number of polymorphic DNA markers developed for the whole human genome during the last 2 years has been vastly increased. For this reason, the genetic map is continuously improving, but the cytogenetic and physical maps are not progressing at the same speed. Therefore, there is a need to integrate genetic, cytogenetic and physical mapping data. We have developed and localized on the breakpoint map of human chromosome 21 thirty microsatellite markers. Twenty of them have been used in the construction of a genetic map of chromosome 21, which contains a total of 44 markers. This map has 39 uniquely placed loci at 23 anchor points, ordered with odds of at least 1,000:1. The sex average length of the map is 64.4 cM, with the male and female lengths being 49.4 and 79.2 cM, respectively. Twenty-six of these newly developed markers have been localised on the CEPH/Généthon and Joint YAC Screening Effort YACs. Although these microsatellites were found uniformly spread along chromosome 21, the detection of various markers in the same or adjacent YACs suggests that CA-repeat microsatellites are clustered in several regions. The localization of these markers on the cytogenetic, genetic and YAC maps has provided a refined location for them and is a step further towards the construction of an integrated map of HC21.

[Mediastinitis secondary to Ludwig's angina. One case report]. / Mediastinitis secundaria a angina de Ludwig. A propósito de un caso.

Ludwig's angina is a cellulitis, usually of odontogenic origin, involving the submandibular space. The number of cases has been heavily lowered since the introduction of antibiotherapy. The treatment consists in an aggressive antibiotherapy and, sometimes, surgical drainage. Complications are: acute respiratory obstruction and spreading of the infection through the neck spaces till the mediastinum. We report one cas complicated with mediastinitis which diagnosis was based in radiological data, basically provided for TAC, The treatment required surgical drainage and antibiotherapy.

[Malignant tumors of external ear. Review of cases in 1991-2001]. / Tumores malignos de conducto auditivo externo. Revisión de nuestra casuística 1991-2001.

Carcinoma of the external auditory canal is a rare tumor. Owing to the rarity of this disease, the literature provides very few publications of series. There is not a widely accepted staging system. The lack of a standarized staging system impedes meaningful interpretation of the literature. It is very difficult to compare different treatment strategies and results. The study is a retrospective case review. Seven patients with external auditory canal malignancies were studied. We used the staging system proposed by Arriaga et al. for both the Squamous cell carcinoma and non-SCC. We describe the risk factors, the symptoms, the treatment and the outcome and prognosis for our patients.

[A bronchogenic cervical cyst. A case report]. / Quiste broncogénico cervical. A propósito de un caso.

The bronchogenic cyst is a tracheobronchial tree congenital malformation, normally intrathoracic. Usually presenting as an acute respiratory insufficiency (especially during infancy) or as recurrent respiratory infections or may be an accidental finding in asymptomatic patients. We present a rare case of cervical localization which began as an acute respiratory distress following a tonsilar infection.

[Recurrent respiratory papillomatosis. Our experience and literature review]. / Papilomatosis respiratoria recurrente. Nuestra experiencia y revisión de la literatura.

The recurrent respiratory papillomatosis is a benign lesion induced by virus, with predisposal factors not yet clear out. Several treatment have been used, being the endoscopic surgery with laser CO2 the most used technique. We present our experience with laryngeal papillomatosis patients operated with laser CO2 in the last 15 years. The high rate of recidive in the youth pattern and the possibility of malignant degeneration in the adults charactherises this patients. Meanwhile without not other concluyent works surgery will be the first therapeutic alternative, avoiding mutilant operations, and paying attention in detecting lesions suggesting malignancy.

[Necrotic sialometaplasia of the hard palate]. / Sialometaplasia necrotizante del paladar duro.

Necrotizing Sialometaplasia is an intrabucal bening pathological change, clinically presented as an ulceration of the hard palate. Either clinically or histologically its resemblance with an squamous carcinoma offers heavy problems of differential diagnosis. The process heals spontaneously in different periods of time. The AA. present 2 cases diagnosed at their Department.

[Pharyngo-laryngeal spindle cell carcinoma]. / Carcinoma fusocelular faringolaríngeo.

Spindle cell carcinoma, a relatively uncommon neoplasia in the otorhinolaryngologic field has a benign polypoid appearance, and often results in diagnostic and therapeutic difficulties. A review of the published literature, and of all of the eight cases we have had in our department has been made, with special attention-being pad to anatomopathologic diagnosis, treatment and prognosis. To sum up, it represents a malignant neoplasia epithelial in origin and of a difficult clinical and pathological diagnosis, which would be more adequately treated by surgical exeresis. It has a worse prognosis than epidermoid carcinoma which is common in this part of the throat.

[Stapedectomy as day case surgery]. / Estapedectomía como cirugía ambulatoria.

Day case surgery is increasing and a large proportion of procedures in otolaryngology are already being performed as day cases. There is less experience in otologic surgery and the reports are specially referred to chronic otitis media. A retrospective study of stapedectomy as a day-case procedure is presented in this report. The inclusion criteria: anaesthesic risk: ASA I, II or III; if the patient has a chronic disease it must be well controlled; they must not have postoperative hemorrhagic history; the patient must be accompanied by an adult the first 24 hours postsurgery; must have a vehicle; distance to hospital must not be more than an hour and they must have a telephone. Between October 1998 and December 2002 71 ambulatory stapedectomies were performed in our institution. 91.2% were discharged home the same day of the procedure. Audiological findings obtained six months after surgery that: 87.5% of the patients have an air-bone Uda of 10 dB or less.

[Treatment with CO2 laser of premalignant glottic epithelial lesions]. / Tratamiento con láser CO2 de las lesiones glóticas leucoplásicas premalignas.

Pre-malignant lesions of the larynx can degenerative into invasive carcinoma. There is not an universally accepted classification and treatment. We present our experience in the treatment with endoscopic CO2 laser for the pre-malignant glottic epithelial lesions. At the same time we carry out a review of the literature published. During a period of ten years we have treated 69 patients with one of these techniques: resection of the epithelial lesion or vaporization. The election of the technique depends on the size of the lesion, the macroscopic aspect, anterior commissures involvement and the surgeons experience. The histological findings were: 53.6% keratosis and 23.2% mid dysplasia both of them treated with vaporization and resection; 14.5% moderate dysplasia and 8.7% severe treated with resection of the lesion. There were no important complications during the operation. Recurrence occurred in 7 patients (10%) but after treatment all of them were free of disease during the follow-up period, they didn't progress to carcinomatosis. 9 patients (13%) had a malignant evolution: 3 keratosis, 1 mild dysplasia, 3 moderate dysplasia and 2 severe dysplasia. Only one case (1.5%) underwent total laryngectomy. The early diagnosis and an appropriate treatment reduced the possibilities of malignant transformation. The therapy with CO2 laser is the treatment of choice in this kind of lesions.

[Laser cordectomy without hospitalization. Is it a safe intervention?]. / Cordectomía láser sin ingreso. Se trata de una intervención segura?

OBJECTIVE: To evaluate the safety of the CO2 Laser Cordectomy in the treatment of glottic carcinoma as a day-case procedure. MATERIAL AND METHODS: Retrospective study of a cohort of 30 patients with glottic carcinoma treated with CO2 Laser Cordectomy at our institution between 1999-2001 as a day-case procedure. RESULTS: There were no major complications and no patients required re-intubation. 90% of the patients were discharged the same day of the procedure. There were three unplanned admissions to the hospital but none of them were, in our opinion, the direct result of Cordectomy. These patients were discharged the next day. 100% of the patients answered that they would repeat the experience. CONCLUSIONS: CO2 Laser Cordectomy of the glottic carcinoma can be safely performed as an outpatient procedure if patients are selected according to specific day-case criteria.

[Palpation and CT to evaluate the cervical adenopathies in head and neck tumours]. / Palpación y TC para evaluar las adenopatías cervicales en los tumores de cabeza y cuello.

Lymphatic metastasis is an important prognostic factor in patients with head and neck squamous cell carcinomas. Diagnostic evaluation and treatment of this adenopathies is very important. We can use physical examination, computered tomography (CT), magnetic resonance, ultrasound... but none of these give us a 100% security. This study evaluates the accuracy of physical examination and CT in detecting cervical lymph nodes. 120 neck dissections were performed after palpation and CT of 72 patients with head and neck carcinoma. Sensitivity of palpation was 51.7 and specificity 96.7. CTs sensitivity was 65 and specificity 86.7. Both, physical examination and palpation have a high number of mistakes evaluating cervical nodes. N0 necks are still a problem for Head and Neck Surgeons.

[Prevalence of exostoses among surfers of the Basque Coast]. / Prevalencia de exóstosis entre surfistas de la Costa Guipuzcoana.

Exostoses of the External Auditory Canal are benign bony tumours very common in individuals who frequently practice water activities. The objective [corrected] of this study is to determine the prevalence of exostoses in a population of surfers of the Basque Coast. We have studied the correlation between years surfing and the prevalence and severity of exostoses. We have done a cross-sectional epidemiological study giving a questionnaire Twenty-five of the 41 surfers had surfer's ear (61%) and the prevalence was significantly higher in those who had surfed for more than 10 years (p < 0.05). Severity was also higher in the first group (p < 0.05). The relation between the hours dedicated to the sport showed similar results. only one of the 24 cases needed surgery (4%).

[The study of the evolution of laryngeal premalignant lesions]. / Estudio evolutivo de lesiones premalignas laríngeas.

Hyperkeratosis of the laryngeal epithelium is considered a clinically premalignant lesion that develops into invasive carcinoma in about 7-20% of cases. We reviewed 125 cases of patients with laryngeal keratosis in biopsy obtained by direct laryngocopy over a 10-year period. The evolution of these lesions to malignancy was conditioned by age, the presence of atypias in the initial lesions, and smoking; smoking is a modifiable factor. Surgery is the treatment of choice, with periodic follow-up for three to five years. The literature was reviewed.