How can we possibly resolve the planet's nitrogen dilemma?

Nitrogen is the most crucial element in the production of nutritious feeds and foods. The production of reactive nitrogen by means of fossil fuel has thus far been able to guarantee the protein supply for the world population. Yet, the production and massive use of fertilizer nitrogen constitute a major threat in terms of environmental health and sustainability. It is crucial to promote consumer acceptance and awareness towards proteins produced by highly effective microorganisms, and their potential to replace proteins obtained with poor nitrogen efficiencies from plants and animals. The fact that reactive fertilizer nitrogen, produced by the Haber Bosch process, consumes a significant amount of fossil fuel worldwide is of concern. Moreover, recently, the prices of fossil fuels have increased the cost of reactive nitrogen by a factor of 3 to 5 times, while international policies are fostering the transition towards a more sustainable agro-ecology by reducing mineral fertilizers inputs and increasing organic farming. The combination of these pressures and challenges opens opportunities to use the reactive nitrogen nutrient more carefully. Time has come to effectively recover used nitrogen from secondary resources and to upgrade it to a legal status of fertilizer. Organic nitrogen is a slow-release fertilizer, it has a factor of 2.5 or higher economic value per unit nitrogen as fertilizer and thus adequate technologies to produce it, for instance by implementing photobiological processes, are promising. Finally, it appears wise to start the integration in our overall feed and food supply chains of the exceptional potential of biological nitrogen fixation. Nitrogen produced by the nitrogenase enzyme, either in the soil or in novel biotechnology reactor systems, deserves to have a 'renaissance' in the context of planetary governance in general and the increasing number of people who desire to be fed in a sustainable way in particular.

Diagnosis and therapeutic management of iatrogenic parotid sialocele.

Salivary gland sialoceles are relatively common and may be a complication of trauma with a penetrating salivary gland injury or may be a complication of salivary gland surgery. The development of new diagnostic tools such as magnetic resonance sialography and endoscopic techniques has led to further improvements in the clinical and diagnostic assessment of this condition, and botulinum toxin therapy has recently been described in the management of parotid sialoceles. We here report the case of a 41-year-old patient with an unusually complicated parotid sialocele following an unsuccessful attempt to remove a stone located in the distal third of Stensen's duct. Magnetic resonance sialography and sialoendoscopy were used in order to obtain an adequate diagnostic assessment. The patient underwent extracorporeal lithotripsy that led to partial symptom regression. After the development of a parotid abscess, he received antibiotics and a botulinum toxin type A injection that induced spontaneous drainage and disappearance of the symptoms. Magnetic resonance sialography and sialoendoscopy are promising new diagnostic techniques for better noninvasive management of iatrogenic sialoceles.

Extracorporeal lithotripsy for salivary calculi: a long-term clinical experience.

OBJECTIVES/HYPOTHESIS: The objective was to assess in a large series of patients with a long-term clinical follow-up the validity of extracorporeal electromagnetic shock wave lithotripsy as a minimally invasive therapy for sialolithiasis. STUDY DESIGN: Consecutive patient series. METHODS: Three hundred twenty-two consecutive symptomatic outpatients with single or multiple calculi in the submandibular (234 patients) or parotid (88 patients) gland underwent a complete extracorporeal electromagnetic shock wave lithotripsy treatment. Treatment results were classified into three groups: successful result with complete ultrasonographic elimination of the stone after lithotripsy, successful result with residual ultrasonographic fragments that were less than 2 mm in diameter, and unsuccessful result with residual ultrasonographic fragments that were greater than 2 mm in diameter. Univariate and multivariate statistical analyses were performed. RESULTS: Complete elimination of the stone was achieved in 45% of patients. On ultrasonography, residual fragments (<2 mm in diameter) were detected in 27.3% of patients, and persisting fragments greater than 2 mm in diameter were assessed in 27.7% of patients. In 3.1% of patients, all with submandibular gland stones, sialoadenectomy was performed. Recurrence of calculi in the treated gland was observed during a median follow-up period of 57 months in four patients with complete ultrasonographic clearance of the stone occurring 10 to 58 months after lithotripsy. Univariate analysis showed that a favorable treatment result was significantly associated with the younger age of the patients (< or = 46 y), parotid and intraductal localization of the stone, diameter of the stone (< or = 7 mm), and number of therapeutic sessions (< or = 6). On multivariate analysis, the age of the patient, parotid site of the stone, stone diameter, number of therapeutic sessions, and number of shock waves were associated with favorable outcome. CONCLUSION: Extracorporeal electromagnetic shock wave lithotripsy is to be considered an efficient, minimally invasive treatment modality for salivary calculi.

Argon plasma coagulation in the treatment of nonallergic hypertrophic inferior nasal turbinates.

PURPOSE: Various surgical procedures have been recently proposed for the treatment of hypertrophic inferior nasal turbinates as a result of the advances made in medical technology and growing public demand for minimally invasive therapies. The aim of this study was to evaluate the safety and efficacy of the argon plasma coagulation technique for inferior turbinate reduction in a homogeneous series of patients with nonallergic inferior turbinate hypertrophy. MATERIAL AND METHODS: Twenty symptomatic patients underwent argon plasma coagulation surgical treatment under local anesthesia and were clinically followed up after 1 month and then every 3 months (anterior rhinoscopy and nasal endoscopy). Diagnostic evaluations using active anterior rhinomanometry were made after 3 and 12 months. RESULTS: All of the patients reported a postoperative improvement in nasal swelling and patency. No postoperative complications were observed. Rhinomanometry after 12 months showed a reduction in mean total resistance from the pretreatment level of 1.06 Pa s/cm(3) to 0.49 Pa s/cm(3). There was also a statistically significant reduction in nasal resistance for each of the investigated conditions (inspiration and expiration in orthostatism and clinostatism). CONCLUSIONS: Argon plasma coagulation is a safe and efficacious procedure for the minimally invasive treatment of inferior turbinate hypertrophy, which can be performed under local anesthesia in an outpatient setting with little discomfort for the patient.