Bio-organic materials in the atmosphere and snow: measurement and characterization.

Bio-organic chemicals are ubiquitous in the Earth's atmosphere and at air-snow interfaces, as well as in aerosols and in clouds. It has been known for centuries that airborne biological matter plays various roles in the transmission of disease in humans and in ecosystems. The implication of chemical compounds of biological origins in cloud condensation and in ice nucleation processes has also been studied during the last few decades, and implications have been suggested in the reduction of visibility, in the influence on oxidative potential of the atmosphere and transformation of compounds in the atmosphere, in the formation of haze, change of snow-ice albedo, in agricultural processes, and bio-hazards and bio-terrorism. In this review we critically examine existing observation data on bio-organic compounds in the atmosphere and in snow. We also review both conventional and cutting-edge analytical techniques and methods for measurement and characterisation of bio-organic compounds and specifically for microbial communities, in the atmosphere and snow. We also explore the link between biological compounds and nucleation processes. Due to increased interest in decreasing emissions of carbon-containing compounds, we also briefly review (in an Appendix) methods and techniques that are currently deployed for bio-organic remediation.

Effect of renal injury-induced neurogenic hypertension on NO synthase, caveolin-1, AKt, calmodulin and soluble guanylate cyclase expressions in the kidney.

Single injection of a small quantity of phenol into the cortex of one kidney in rats results in development of persistent hypertension (HTN) which is thought to be mediated by activation of renal afferent and efferent sympathetic pathways and sodium retention. Nitric oxide (NO) plays a major role in regulation of renal vascular resistance, tubular Na(+) reabsorption, pressure natriuresis, and thereby systemic arterial pressure. The present study was performed to test the hypothesis that chronic renal injury-induced HTN may be associated with dysregulation of NO system in the kidney. Accordingly, urinary NO metabolite (NO(x)) and cGMP excretions as well as renal cortical tissue (right kidney) expressions of NO synthase (NOS) isoforms [endothelial, neuronal, and inducible NOS, respectively (eNOS, nNOS, and iNOS)], NOS-regulatory factors (Caveolin-1, phospho-AKt, and calmodulin), and second-messenger system (soluble guanylate cyclase [sGC] and phosphodiesterase-5 [PDE-5]) were determined in male Sprague-Dawley rats 4 wk after injection of phenol (50 mul of 10% phenol) or saline into the lower pole of left kidney. The phenol-injected group exhibited a significant elevation of arterial pressure, marked reductions of urinary NO(x) and cGMP excretions, downregulations of renal tissue nNOS, eNOS, Phospho-eNOS, iNOS, and alpha chain of sGC. However, renal tissue AKt, phospho-AKT, Calmodulin, and PDE-5 proteins were unchanged in the phenol-injected animals. In conclusion, renal injury in this model results in significant downregulations of NOS isoforms and sGC and consequent reductions of NO production and cGMP generation by the kidney, events that may contribute to maintenance of HTN in this model.

CT-guided interventional procedures for pain management in the lumbosacral spine.

The lumbosacral spine is the source of pain, suffering, and disability more frequently than any other part of the body. Pain in the lower back can be managed with computed tomography-guided analgesic interventional procedures, such as periradicular infiltration, percutaneous laser disk decompression, facet joint block, and percutaneous vertebroplasty. Periradicular injection of steroids provides short-term and sometimes even long-term relief of low back pain. Percutaneous laser disk decompression is used to treat radiculalgia caused by disk herniation. Facet joint block is useful in diagnosis and treatment of facet syndrome. Percutaneous vertebroplasty provides short- and long-term pain relief in patients with vertebral body disease. However, precise patient selection is essential to the success of each of these techniques. The interventional radiologist has an active role to play in minimally invasive management of lower back pain and should be part of an interdisciplinary team that determines the appropriate therapy.

Percutaneous laser photocoagulation of spinal osteoid osteomas under CT guidance.

BACKGROUND AND PURPOSE: Spinal osteoid osteomas are rare; when they occur, they are usually treated by surgical or percutaneous excision. The aim of percutaneous interstitial laser photocoagulation (ILP) of osteoid osteomas under CT guidance is thermal destruction of the nidus using low-power laser energy, thus precluding bone resection and open surgery. METHODS: Three cases of spinal osteoid osteomas were treated with percutaneous ILP of the nidus. Under CT guidance, the needle was positioned in the center of the nidus, at least 8 mm from neurologic structures. Using a high-power semiconductor diode laser (805 nm) with a 400-microm optical fiber, we delivered 600 to 800 joules to the nidus, depending on its size. The procedure was performed with the patient under neuroleptanalgesia and required overnight hospitalization. RESULTS: Complete pain relief was obtained in all three patients within 24 hours of the procedure, and no major complications were incurred. Follow-up ranged from 20 months to 60 months. CONCLUSION: Percutaneous ILP of spinal osteoid osteoma is a promising, simple, precise, and minimally invasive technique and may be an alternative to traditional surgical and percutaneous ablations.

[Treatment of osteoid osteoma using laser photocoagulation. Apropos of 28 cases]. / Traitement des ostéomes ostéoïdes par photocoagulation au laser. A propos de 28 cas.

UNLABELLED: THE PURPOSE OF THE STUDY was to evaluate interstitial laser photocoagulation for local destruction of osteoid osteoma, with computed tomographic (CT) guidance. MATERIAL AND METHODS: 28 patients (age range from 5 to 48 years) with presumed osteoid osteoma were treated with CT-guided interstitial laser photocoagulation of the nidus. A high power semiconductor diode laser (805 nm) with a 400 microns optical fiber was used. The fiber was introduced into the nidus through a 18-gauge needle. Around the fiber tip, well-defined coagulative necroses from 5 to 9 mm (energy delivery, 400-1000J) were obtained. RESULTS: 27 patients had complete pain relief, which was effective within 24 hours in 18 patients. One patient had pain recurrence after 6 weeks. The remaining nidus was treated secondarily with complete relief. Treatment was unsuccessful in one patient, and surgical excision was performed. All patients were followed up for more than 1 year, with no sign of recurrence. The only notable complication was a mild reflex sympathetic dystrophy of the wrist in one patient. Sclerosis of the nidus was observed 6-12 months after the procedure. CONCLUSION: Percutaneous interstitial laser photocoagulation of osteoid osteoma seems to be a promising, simple, precise, and minimally invasive alternative to traditional surgical and percutaneous ablations.

Interstitial laser photocoagulation of osteoid osteomas with use of CT guidance.

PURPOSE: To evaluate interstitial laser photocoagulation (a minimally invasive percutaneous technique of thermal destruction of deep-seated tumors, with low-power laser energy) in local destruction of osteoid osteoma, with computed tomographic (CT) guidance. MATERIALS AND METHODS: Fifteen patients (age range, 8-48 years) with presumed osteoid osteoma were treated with CT-guided interstitial laser photocoagulation of the nidus. A high-power semiconductor diode laser (805 nm) with a 400-microm optical fiber was used. The fiber was introduced into the nidus through an 18-gauge needle. Around the fiber tip, well-defined coagulative necroses from 5 to 9 mm (energy delivery, 400-1,000 J) were obtained. RESULTS: Fourteen patients had complete pain relief, which was apparent within 24 hours in eight patients. One patient had recurrence of pain after 6 weeks. The remaining nidus was treated a second time, with complete relief. Treatment was unsuccessful in one patient, and surgical excision was performed. Daily activities were not restricted after the intervention. All patients were followed up for more than 1 year, with no sign of recurrence. The only notable complication was a mild reflex sympathetic dystrophy of the wrist in one patient. Sclerosis of the nidus was observed 4-6 months after the procedure. CONCLUSION: Percutaneous interstitial laser photocoagulation of osteoid osteoma seems to be a promising, simple, precise, and minimally invasive alternative to traditional surgical and percutaneous ablations.

Interventional radiologic procedures with CT guidance in cancer pain management.

Reduction of pain without systematic side effects can be achieved in advanced stages of cancer with precise percutaneous techniques guided with computed tomography (CT). CT guidance allows exact needle positioning, reducing complications and improving the results. Regional analgesia with neurolytic block (neurolysis) is achieved by injection of alcohol or phenol and involves intentional destruction of a nerve or nerves to interrupt nociceptive pathways for weeks or months. Percutaneous alcoholization of bone metastasis is indicated in patients with painful, severe, osteolytic bone metastasis if conventional anticancer therapy is ineffective and high doses of opiates are necessary to control pain and when rapid pain relief is necessary. Bone packing with acrylic glue (methyl methacrylate) is used to prevent pathologic fractures and pain in patients with vertebral body tumors and acetabular metastasis. With these techniques, the radiologist is able to play an active role in pain management and in improving the quality of life of patients with malignancies.