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Refractory
Kinds of Refractory Terms modified by Refractory Selected AbstractsBotulinum Toxin Type B for Dynamic Glabellar Rhytides Refractory to Botulinum Toxin Type ADERMATOLOGIC SURGERY, Issue 5 2003Tina S. Alster MD Background. Botulinum toxin type B (BTX-B; Myobloc) has recently been introduced for the treatment of dynamic rhytides. This serotype is structurally similar to botulinum toxin type A (BTX-A; Botox) and appears to produce equivalent muscular paralysis. Because of the fact that some patients may become resistant to the effects of BTX-A with its continued use or may require large doses of type A to exert adequate muscular paralysis, the use of BTX-B may prove beneficial in these cases. Objective. To determine the effect of BTX-B on glabellar rhytides refractory or showing decreased clinical effect to treatment with BTX-A. Methods. Twenty females (mean age, 43 years) with vertical glabellar rhytides showing decreased or negligible clinical effect to BTX-A were treated with intramuscular injections of BTX-B. Five standardized intramuscular sites (procerus, inferomedial corrugator muscles, superior middle corrugator muscles) received a total dose of 2,500 U. Patients were evaluated at pretreatment and 48 to 72 hours, 1 week, and 2 and 4 months after injection. Results. All glabellar rhytides improved after treatment with BTX-B injections. Peak clinical effect was noted 1 month after treatment, with 50% of peak effect evident at the 2-month follow-up. Near complete dissolution of effect was seen at 4 months after treatment. Side effects were transient and were limited to moderate injectional pain and rare bruising and frontal brow tightness. Conclusions. BTX-B is an effective treatment modality for glabellar rhytides refractory or exhibiting decreased clinical effect to BTX-A. The duration of effect using the 2,500 U dosing schedule described herein was shorter than that typically achieved after equivalent BTX-A injection. [source] Self-Repairing Function in the Carbon-Containing RefractoryINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 6 2007Akira Yamaguchi Self-repairing function is observed in carbon-containing refractory such as MgO,C, Al2O3,C, and so forth. Non-oxides such as pure metallic, alloys, carbides, and nitrides are intentionally added to the refractory composition to bring about this function. As a basis of the development of a self-repairing refractory, the self-repairing mechanism in the carbon-containing refractory is described. [source] Characteristics of Hypertrophic Obstructive Cardiomyopathy Refractory to Medical Treatment and Selection of Surgical MethodsJOURNAL OF CARDIAC SURGERY, Issue 1 2005Yujiro Hirasawa M.D. Using the classification of systolic anterior movement (SAM) which has been previously reported, we tried to identify the characteristics and use them to treat HOCM appropriately. Methods: The clinical, echocardiographic, catheterization, and surgical data of 29 hospitalized patients with HOCM during 1980 to 1999 were analyzed retrospectively. We classified SAM in all patients by echocardiography. Ninteen patients improved with medical treatment (medical group), and 10 patients underwent surgical treatment because of ineffectiveness of medication (surgical group). We studied the relation between types of SAM and medical/surgical groups, and examined the relation between types of SAM and the surgical methods. Results: Type I SAM was significantly more frequent in the medical group, while type II SAM was more frequent in the surgical group (p = 0.047). Patients in the surgical group underwent mitral valve replacement (MVR), myectomy, or a combination of MVR and myectomy. Left ventricular outflow gradient (LVOG) of over 100 mmHg was recognized in almost all patients with type II SAM. Conclusions: It was suggested that patients with medication-responsive HOCM tended to have type I SAM and those with refractory HOCM tended to have type II SAM. We consider that in type I SAM, if the position of the papillary muscles changed with medication or myectomy, shift of the chordae and type I SAM were reduced or disappeared. However, in type II SAM, even if the position of the papillary muscles changed, SAM did not disappear because lifting of the mitral leaflets remained. It is therefore suggested that patients with type II SAM should undergo at least MVR. [source] Confusing ICD Terminology: Refractory and Blanking PeriodsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2006S. SERGE BAROLD No abstract is available for this article. [source] An Open Pilot Study Assessing the Benefits of Quetiapine for the Prevention of Migraine Refractory to the Combination of Atenolol, Nortriptyline, and FlunarizinePAIN MEDICINE, Issue 1 2010Abouch V. Krymchantowski MD, FAHS ABSTRACT Background., Migraine is a prevalent neurological disorder. Although prevention is the core of treatment for most, some patients are refractory to standard therapies. Accordingly, the aim of this study was to evaluate the use of Quetiapine (QTP) in the preventive treatment of refractory migraine, defined as previous unresponsiveness to the combination of atenolol, nortriptyline, and flunarizine. Methods., Thirty-four consecutive patients (30 women and 4 men) with migraine (ICHD-II), fewer than 15 days of headache per month, and not overusing symptomatic medications were studied. All participants had failed to the combination of atenolol (60 mg/day), nortriptyline (25 mg/day), and flunarizine (3 mg/day). Failure was defined as <50% reduction in attack frequency after 10 weeks of treatment. After other medications were discontinued, QTP was initiated at a single daily dose of 25 mg, and then titrated to 75 mg. After 10 weeks, headache frequency, consumption of rescue medications, and adverse events were analyzed. Results., Twenty-nine patients completed the study. Three patients withdrew and two were lost to follow-up. Among those who completed, 22 (75.9%; 64.7% of the intention-to-treat population) had greater than 50% headache reduction. The mean frequency of migraine days decreased from 10.2 to 6.2 per month. Use of rescue medications decreased from 2.3 to 1.2 days/week. Adverse events were reported by nine (31%) patients. Conclusions., Although limited by the open design, this study provides pilot data to support the use of QTP in the preventive treatment of refractory migraine. Controlled studies are necessary to confirm these observations. [source] Treatment of Refractory, Chronic Low Back Pain with Botulinum Neurotoxin A: An Open-Label, Pilot StudyPAIN MEDICINE, Issue 3 2006Bahman Jabbari MD ABSTRACT Objective., To study the short- and long-term effects of botulinum neurotoxin A (BoNT-A, Botox®, Allergan Inc.) on refractory chronic low back pain. Design., The effect of botulinum neurotoxin A on chronic low back pain was prospectively studied in 75 patients with repeated treatments over a period of 14 months. Pain intensity (visual analog scale [VAS]), pain frequency (pain days), and perceived functional status (Oswestry scale) were assessed at baseline, 3 weeks, and at 2, 4, 6, 8, 10, 12, and 14 months. BoNT-A was injected into para-spinal muscles at 4,5 levels (between L1 and S1) unilaterally or bilaterally. The dose per site varied from 40 to 50 units. The total dose per session ranged from 200 to 500 units. Reinjections were performed at 4 months only when pain returned. Results., At 3 weeks, 40 patients (53%) and at 2 months, 39 patients (52%) reported significant pain relief. The change in VAS, Oswestry score, and pain days was significant compared with baseline at 2 months after each injection period (P < 0.005) and remained so over subsequent treatments. Among initial responders, 91% continued responsiveness over the length of the study. Three patients (4%), after the first treatment, had a mild flulike reaction that lasted 2,5 days. Conclusion., Botulinum neurotoxin A may be beneficial in patients with chronic low back pain. A favorable initial response predicts subsequent responsiveness. The treatment is well tolerated, and side effects are mild and transient. [source] Acute encephalitis with refractory, repetitive partial seizures (AERRPS): a peculiar form of childhood encephalitisACTA NEUROLOGICA SCANDINAVICA, Issue 4 2010H. Sakuma Sakuma H, Awaya Y, Shiomi M, Yamanouchi H, Takahashi Y, Saito Y, Sugai K, Sasaki M. Acute encephalitis with refractory, repetitive partial seizures (AERRPS): a peculiar form of childhood encephalitis. Acta Neurol Scand: 2010: 121: 251,256. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective,,, We conducted a nationwide multicenter study in Japan to elucidate the clinical and laboratory characteristics of acute encephalitis with refractory, repetitive partial seizures (AERRPS). Materials and methods,,, Clinical and laboratory features, treatment, and outcome were assessed using a structured questionnaire. Results,,, Twenty-nine children were enrolled in the study. Refractory and repetitive partial seizures accompanied by fever were the cardinal clinical features. Partial seizures consisted principally of eye deviation or facial twitching, being periodically repeated during the acute phase. These seizures were refractory to conventional anticonvulsants and were only suppressed by high-dose intravenous barbiturate administration. Rhythmic activities on electroencephalography and non-specific cerebral atrophy on neuroimaging were common. Serum or cerebrospinal antibodies against GluR,2 were positive in six patients. General prognosis was unfavorable due to intractable epilepsy and cognitive deficits. Conclusion,,, Based on the peculiar and homogenous features, AERRPS can be regarded as a distinct clinical entity. [source] Thermal Conductivity of Monazite-Type REPO4 (RE=La, Ce, Nd, Sm, Eu, Gd)JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2009Aibing Du Low-thermal conductivity ceramics in monazite-type REPO4 (RE=La, Ce, Nd, Sm, Eu, Gd) ceramics are expected to have potential in structural (refractories, thermal insulator) and nuclear applications. To this end, the present study determines their thermal conductivities and examines how differences of the rare earth ions change their thermal conductivity at different temperatures. The results show that their conductivities are remarkably low from 25° to 1000°C. In addition, different conductivity variation mechanisms exist that change gradually upon altering from LaPO4 to GdPO4 at low and high temperatures. At relatively lower temperatures (,400°C), the thermal conductivities of all the REPO4 ceramics decrease nearly at first, reach a minimum value, and then rise with gradual altering from LaPO4 to GdPO4. It may be due to the combined effects of the increase of both the anharmonicities in lattice vibrations and the bond strength. As the temperature increases, the conductivity trends become obscure, and the conductivities of the monazite-type REPO4 approach their minimum thermal conductivities when the temperature is above 800°C. [source] Oxidation Protection of MgO,C Refractories by Means of Al8B4C7JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2001Tianming Wang The effect of Al8B4C7 used as an antioxidant in MgO,C refractories and the behavior of Al8B4C7 in CO gas were investigated in the present study. Al8B4C7 was found to react with CO gas, to form Al2O3(s), B2O3(l), and C(s), at temperatures >1100°C. The Al2O3 reacts with MgO to form MgAl2O4 near the surface of the material. At the same time, B2O3(l) evaporates and reacts with MgO, to form a liquid phase, at >1333°C, the eutectic point between 3MgO·B2O3 and MgO. The coexistence of the liquid and MgAl2O4 makes the protective layer more dense, thus inhibiting oxidation of the refractory. At >1333°C, the process apparently is controlled by oxygen diffusion, whereas it is controlled by chemical reaction when the temperature is <1333°C. [source] Long-Term Efficacy of Subcutaneous Sweat Gland Suction Curettage for Axillary Hyperhidrosis: A Prospective Gravimetrically Controlled StudyDERMATOLOGIC SURGERY, Issue 9 2008STEPHANIE DARABANEANU PHD BACKGROUND Subcutaneous sweat gland suction curettage (SSGSC) is gaining acceptance as a therapy for axillary hyperhidrosis. Despite its acceptance, there remains a lack of prospective data describing the efficacy and long-term outcome of SSGSC. OBJECTIVE We examined the sweat rates and patients' satisfaction of 12 months following SGSC in 28 patients with axillary hyperhidrosis. METHODS Axillary sweat rates were determined by semiquantitative gravimetry. A questionnaire was used to determine patients' satisfaction. RESULTS A 58% reduction in sweat rate under resting conditions and an 85% reduction during aerobic exercise in sweat rates was observed. A subdivision of patients into three groups based on their baseline preoperative sweat rates (<25, 25,50, and >50 mg/min) showed that patients with resting sweat rates over 25 mg/min benefited particularly from this procedure, whereas patients with less than 25 mg/min did not. CONCLUSION SSGSC produces a significant reduction in the preoperative sweat rates. A low complication rate and a high degree of patient satisfaction were observed. Long-term follow-up evaluations demonstrate a low number of relapses, making SSGSC a convenient and satisfactory method of treating axillary hyperhidrosis. It should be considered in patients refractory to conventional therapies with baseline sweat rates greater than 25 mg/min. [source] Surgical Approaches for Stable VitiligoDERMATOLOGIC SURGERY, Issue 10 2005Rafael Falabella MD Background. Vitiligo therapy is difficult. Depending on its clinical presentation, unilateral or bilateral vitiligo lesions respond well with different repigmentation rates, according to age, affected anatomic area, extension of lesions, time at onset, timing of depigmentation spread, and other associated factors. When stable and refractory to medical treatment, vitiligo lesions may be treated by implanting pigment cells on depigmented areas. Objective. To describe the main events of depigmentation and the fundamentals of surgical techniques for repigmenting vitiligo by implanting noncultured cellular or tissue grafts, in vitro cultured epidermis-bearing pigment cells, or melanocyte suspensions. Methods. A description of the available techniques for repigmentation of vitiligo is done, emphasizing the most important details of each procedure to obtain the best repigmentation and minimize side effects. Results. With most of these techniques, adequate repigmentation is obtained, although there are limitations when applying some methods to clinical practice. Conclusions. Restoration of pigmentation may be accomplished with all available surgical procedures in most anatomic locations, but they are of little value for acral areas. Unilateral vitiligo responds well in a high proportion of patients, and bilateral disease may also respond when stable. Appropriate patient selection is important to achieve the best results. [source] Intense Pulsed Light for the Treatment of Refractory Melasma in Asian PersonsDERMATOLOGIC SURGERY, Issue 9 2004Chia-Chen Wang MD Background. Patients with dermal or mixed-type melasmas are often refractory to various treatments. Intense pulsed light has been used to treat melanocytic lesions with promising results. Objective. The purpose of this study was to clarify the effectiveness of intense pulsed light for refractory melasma in Asian persons. Methods. Seventeen patients were treated with intense pulsed light, during four sessions at 4-week intervals. The patients were also given 4% hydroquinone cream and broad-spectrum sunscreens to prevent and treat postinflammatory hyperpigmentation. Sixteen patients in the control group were treated with hydroquinone cream and sunscreens. The treatment efficacy was evaluated using reflectance spectrophotometer and patient satisfaction questionnaire. Results. Patients in the intense pulsed light group achieved an average of 39.8% improvement in relative melanin index, compared to 11.6% improvement in the control group (p<0.05) at Week 16. Six (35%) patients in the intense pulsed light group had more than 50% improvement, compared to two (14%) patients in the control group. Two patients in the intense pulsed light group, however, experienced transient postinflammatory hyperpigmentation, and partial repigmentation was noted 24 weeks after the last treatment session. Conclusion. Intense pulsed light is a safe and effective treatment for refractory melasma in Asian persons, with minimal side effects. Further treatment sessions are required for maintenance therapy. [source] Botulinum Toxin Type B for Dynamic Glabellar Rhytides Refractory to Botulinum Toxin Type ADERMATOLOGIC SURGERY, Issue 5 2003Tina S. Alster MD Background. Botulinum toxin type B (BTX-B; Myobloc) has recently been introduced for the treatment of dynamic rhytides. This serotype is structurally similar to botulinum toxin type A (BTX-A; Botox) and appears to produce equivalent muscular paralysis. Because of the fact that some patients may become resistant to the effects of BTX-A with its continued use or may require large doses of type A to exert adequate muscular paralysis, the use of BTX-B may prove beneficial in these cases. Objective. To determine the effect of BTX-B on glabellar rhytides refractory or showing decreased clinical effect to treatment with BTX-A. Methods. Twenty females (mean age, 43 years) with vertical glabellar rhytides showing decreased or negligible clinical effect to BTX-A were treated with intramuscular injections of BTX-B. Five standardized intramuscular sites (procerus, inferomedial corrugator muscles, superior middle corrugator muscles) received a total dose of 2,500 U. Patients were evaluated at pretreatment and 48 to 72 hours, 1 week, and 2 and 4 months after injection. Results. All glabellar rhytides improved after treatment with BTX-B injections. Peak clinical effect was noted 1 month after treatment, with 50% of peak effect evident at the 2-month follow-up. Near complete dissolution of effect was seen at 4 months after treatment. Side effects were transient and were limited to moderate injectional pain and rare bruising and frontal brow tightness. Conclusions. BTX-B is an effective treatment modality for glabellar rhytides refractory or exhibiting decreased clinical effect to BTX-A. The duration of effect using the 2,500 U dosing schedule described herein was shorter than that typically achieved after equivalent BTX-A injection. [source] Microabrasion Versus Microabrasion Followed by 15% Trichloroacetic Acid for Treatment of Cutaneous Hyperpigmentations in Adult FemalesDERMATOLOGIC SURGERY, Issue 4 2003Claudia Cotellessa MD BACKGROUND Cutaneous hyperpigmentations are common skin disorders that are often refractory to currently available treatments. OBJECTIVE To evaluate the efficacy of microabrasion alone or microabrasion with 15% trichloroacetic acid (TCA) for treatment of cutaneous hyperpigmentations. METHODS Twenty female patients were treated with microabrasion alone every 2 weeks (group 1), and 20 female patients were treated with microabrasion and application of 15% TCA every 3 weeks (group 2). All patients underwent up to eight treatments. The overall duration of treatment ranged from 2 to 4 months. RESULTS In group 1, a complete remission was observed in 8 of 20 cases (40%), partial remission in 10 of 20 cases (50%), and no remission in 2 of 20 cases (10%). In group 2, a complete remission was observed in 10 of 20 cases (50%), a partial remission in 8 of 20 cases (40%), and no remission in 2 of 20 cases (10%). No unexpected or serious side effects were observed in either group. CONCLUSIONS Microabrasion alone or microabrasion with 15% TCA is an effective, well-tolerated treatment for cutaneous hyperpigmentations. [source] Therapeutic Hotline: Treatment of prurigo nodularis and lichen simplex chronicus with gabapentinDERMATOLOGIC THERAPY, Issue 2 2010Gulsum Gencoglan ABSTRACT Psychocutaneous conditions are frequently encountered in dermatology practice. Prurigo nodularis and lichen simplex chronicus are two frustrating conditions that are classified in this category. They are often refractory to classical treatment with topical corticosteroids and antihistamines. Severe, generalized exacerbations require systemic therapy. Phototherapy, erythromycine, retinoids, cyclosporine, azathiopurine, naltrexone, and psychopharmacologic agents (pimozide, selective serotonin reuptake inhibitor antidepressants) were tried with some success. Here five cases with lichen simplex chronicus and four cases with prurigo nodularis, who responded well to gabapentin, are presented. [source] Adalimumab for treatment of moderate to severe psoriasis and psoriatic arthritisDERMATOLOGIC THERAPY, Issue 2008M. R. Bongiorno ABSTRACT: Psoriasis and psoriatic arthritis are common diseases associated with considerable morbidity and disability. Their pathophysiology comprises similar processes leading to inflammation of skin, entheses, and joints. Although traditional systemic agents can be effective, their use may be limited by lack of efficacy and concerns regarding adverse effects. The objective of this study was to assess the efficacy and safety of adalimumab, a fully human antitumor necrosis factor (anti-TNF) monoclonal antibody, over 16 weeks. The present authors report their personal experience in 15 patients with severe plaque psoriasis and psoriatic arthritis, refractory to other treatments, in which a decisive regression of joint/skin involvement was obtained. Psoriasis and psoriatic arthritis are chronic inflammatory disorders resulting from a combination of genetic and environmental factors. [source] Prospective studies of suicidal behavior in major depressive and bipolar disorders: what is the evidence for predictive risk factors?ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2006M. A. Oquendo Objective:, Prospective studies over the past 30 years have identified an array of predictive indicators for suicidal acts in mood disorders. However, prediction of suicidal behavior remains an elusive goal. This paper reviewed evidence from prospective studies for clinical factors that elevate risk of suicidal acts in that group. Method:, English language prospective studies of suicidal behavior in major depressive and bipolar disorders were examined. Results:, The predictors with the best support were a past history of suicidal behavior and the presence of refractory or recurrent depressions. For other risk factors, there was either not enough data to consider them robust or findings were contradictory. Conclusion:, Future studies must not only be comprehensive in their inclusion of potentially contributing factors, but must also address their relative importance towards the goal of developing predictive models and enhance suicide prevention efforts. [source] Intraocular pigmented proliferations in the context of cytologic evaluationDIAGNOSTIC CYTOPATHOLOGY, Issue 11 2009F.I.A.C.Article first published online: 22 JUL 200, Lourdes R. Ylagan M.D. Abstract This article is written to give an overview of the various intraocular pigmented proliferations as it pertains to cytologic evaluation and interpretation. It reviews the various epithelial and melanocytic lesions, their location and the various clinical approaches the ophthalmologist uses to aspirate the lesion. It also reviews the current thinking in the differentiation between Class I and Class II melanomas and how molecular profiling may be necessary in its differentiation which could help stratify those patients whose tumors are refractory to treatment and may benefit from adjuvant chemotherapy and eye-sparing surgery. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Association between oestradiol and puerperal psychosisACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2000A. Riecher-Rössler Objective: Postpartum psychiatric disorders with long-lasting adverse sequelae are common during the childbearing years. These disorders can be severe and resistant to conventional psychiatric treatment methods. We present two consecutive cases with puerperal psychosis who were refractory to conventional treatment methods but responded successfully to oestrogen therapy. Method: Serum oestradiol concentration was measured by radioimmunoassay and the documented oestradiol deficiency replaced with physiological oestradiol sublingually. The treatment effect was evaluated by the Brief Psychiatric Rating Scale. Results: In both cases the baseline oestradiol concentration was low (28 and 69 pmol/L). During the treatment with oestradiol, there was a concomitant elevation of the concentration of serum oestradiol, which coincided with the decline in psychotic symptoms. Conclusion: The observation of low serum oestradiol together with psychotic symptoms and successful treatment with oestradiol suggests that oestradiol may have a causal relevance to puerperal psychosis and significance in the treatment of this condition. [source] REFRACTORY DIVERTICULAR COLITIS WITH PROGRESSIVE ULCERATIVE COLITIS-LIKE CHANGES EXTENDING TO THE RECTUMDIGESTIVE ENDOSCOPY, Issue 3 2009Tateki Yamane A 68-year-old man visited our department because of diarrhea and bloody stools. Colonoscopy revealed diverticula scattered in the sigmoid colon with localized mucosal edema and reddening. The mucosa became somewhat rough 9 months later, and had an erosive, ulcerative colitis (UC)-like appearance after a further 6 months, with these changes extending to the rectum. These findings led to a diagnosis of diverticular colitis (DC) with UC-like changes. The condition was refractory to treatment including drug therapy and was thus surgically treated. No cases of DC have been reported in Japan, and a refractory case of DC with progressive UC-like changes extending to the rectum is rare even in Europe and the USA. [source] Laparoscopic paraesophageal hernia repair: quality of life outcomes in the elderlyDISEASES OF THE ESOPHAGUS, Issue 8 2008E. J. Hazebroek SUMMARY Paraesophageal hernias (PEH) occur when there is herniation of the stomach through a dilated hiatal aperture. These hernias occur more commonly in the elderly, who are often not offered surgery despite the failure of medical treatment to address mechanical symptoms and life-threatening complications. The aim of this study was to assess the impact of laparoscopic repair of PEH on quality of life in an elderly population. Data were collected prospectively on 35 consecutive patients aged >70 years who had laparoscopic repair of a symptomatic PEH between December 2001 and September 2005. The change in quality of life was assessed using a validated questionnaire, the Quality of Life in Reflux and Dyspepsia questionnaire (QOLRAD), and by patient interviews. Patients were assessed preoperatively, and at 6 weeks, 6 months, 12 months, 1 year, and 2 years postoperatively. Mean patient age was 77 years (range 70,85); mean American Society of Anesthesiologists class was 2.7 (range 1,3). There were 28 women and 7 men. There was one readmission for acute reherniation, which required open revision. Total complication rate was 17.1%. All complications were treated without residual disability. There was no 30-day mortality, and median hospital stay was 3 days (range 2,14). Completed questionnaires were obtained in 30 of 35 patients (85.7%). There was a significant improvement in quality of life, as measured with QOLRAD, at all postoperative time points (P < 0.001). Laparoscopic PEH repair can be performed with acceptable morbidity in symptomatic patients refractory to conservative treatment and is associated with a significant improvement in quality of life. Our data support elective repair of symptomatic PEH in the elderly, a population who may not always be referred for a surgical opinion. [source] Using Rock-Eval 6 pyrolysis for tracking fossil organic carbon in modern environments: implications for the roles of erosion and weatheringEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2006Yoann Copard Abstract This work relates to the debate on the fossil organic carbon (FOC) input in modern environments and its possible implication for the carbon cycle, and suggests the use of Rock-Eval 6 pyrolysis as a relevant tool for tracking FOC in such environments. Considering that such a delivery is mainly due to supergene processes affecting the continental surface, we studied organic matter in different reservoirs such as bedrocks, alterites, soils and rivers in two experimental catchments at Draix (Alpes de Haute Provence, France). Samples were subjected to geochemical (Rock-Eval 6 pyrolysis) investigations and artificial bacterial degradations. After comparing the geochemical fingerprint of samples, geochemical markers of FOC were defined and tracked in the different reservoirs. Our results confirm the contribution of FOC in modern soils and rivers and display the various influences of weathering and erosional processes on the fate of FOC during its exchange between these pools. In addition, the contrasting behaviour of these markers upon the supergene processes has also highlighted the refractory or labile characters of the fossil organic matter (FOM). Bedrock to river fluxes, controlled by gully erosion, are characterized by a qualitative and quantitative preservation of FOM. Bedrock to alterite fluxes, governed by chemical weathering, are characterized by FOC mineralization without qualitative changes in deeper alterites. Alterite to soils fluxes, controlled by (bio)chemical weathering, are characterized by strong FOC mineralization and qualitative changes of FOM. Thus weathering and erosional processes induce different FOM evolution and affect the fate of FOC towards the global carbon cycle. In this study, gully erosion would involve maintenance of an ancient sink for the global carbon cycle, while (bio)chemical processes provide a source of CO2. Finally, this study suggests that Rock-Eval 6 pyrolysis can be considered as a relevant tool for tracking FOC in modern environments. Copyright © 2006 John Wiley & Sons, Ltd. [source] THE 1930s AND THE PRESENT DAY , CRISES COMPAREDECONOMIC AFFAIRS, Issue 4 2009Panagiotis Evangelopoulos Many analysts are comparing the deep crisis of our times with the crash of 1929 and the Great Depression that followed in the 1930s. They generally argue that Barack Obama is driving the world to recovery along Roosevelt's ,state superiority' line. Alas, today's crisis rings alarm bells for the manner in which we must manage the future of democracy, the state and markets. Markets cannot be ,ordered about' and when in the face of sound logic and practice an attempt is made to do just this, markets become refractory, or , even worse , they may collapse. [source] Anaphylaxis: Clinical concepts and research prioritiesEMERGENCY MEDICINE AUSTRALASIA, Issue 2 2006Simon GA Brown Abstract Anaphylaxis is a severe immediate-type hypersensitivity reaction characterized by life-threatening upper airway obstruction bronchospasm and hypotension. Although many episodes are easy to diagnose by the combination of characteristic skin features with other organ effects, this is not always the case and a workable clinical definition of anaphylaxis and useful biomarkers of the condition have been elusive. A recently proposed consensus definition is ready for prospective validation. The cornerstones of management are the supine position, adrenaline and volume resuscitation. An intramuscular dose of adrenaline is generally recommended to initiate treatment. If additional adrenaline is required, then a controlled intravenous infusion might be more efficacious and safer than intravenous bolus administration. Additional bronchodilator treatment with continuous salbutamol and corticosteroids are used for severe and/or refractory bronchospasm. Aggressive volume resuscitation, selective vasopressors, atropine (for bradycardia), inotropes that bypass the ,-adrenoreceptor and bedside echocardiographic assessment should be considered for hypotension that is refractory to treatment. Management guidelines continue to be opinion- and consensus-based, with retrospective studies accounting for the vast majority of clinical research papers on the topic. The clinical spectrum of anaphylaxis including major disease subgroups requires clarification, and validated scoring systems and outcome measures are needed to enable good-quality prospective observational studies and randomized controlled trials. A systematic approach with multicentre collaboration is required to improve our understanding and management of this disease. [source] Selection of refractory for thermal oxidizers on gas streams containing fluorineENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2002Stanley C. Che Thermal oxidizers for destruction of fluorine-containing chemicals are typically operated between 1,100° to 1,400° C. Fluorine is converted to hydrogen fluoride (HF) during the combustion process. At high temperatures, HF will react with almost all materials. Proper selection of the refractory material used by the thermal oxidizer is essential for long-term use, and to protect the metal shell from corrosion. Selection criteria should include analysis of chemical composition, physical properties, morphology, and bonding phases. A high alumina brick from a thermal oxidizer was analyzed after it had been in service for one year. The brick surface underwent significant changes of its chemical and micro-structural compositions. Silica in the mullite phase had reacted with HF, leaving only corundum. In the inner part of the brick, both mullite and corundum crystals still existed. Refractory selection guidelines are suggested. [source] The Prestige oil spill.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005Abstract In vitro biodegradation of the Prestige heavy fuel oil has been carried out using two microbial consortia obtained by enrichment in different substrates to simulate its environmental fate and potential utility for bioremediation. Different conditions, such as incubation time (i.e., 20 or 40 d), oil weathering, and addition of an oleophilic fertilizer (S200), were evaluated. Weathering slowed down the degradation of the fuel oil, probably because of the loss of lower and more labile components, but the addition of S200 enhanced significantly the extension of the biodegradation. n -Alkanes, alkylcyclohexanes, alkylbenzenes, and the two- to three-ring polycyclic aromatic hydrocarbons (PAHs) were degraded in 20 or 40 d of incubation of the original oil, whereas the biodegradation efficiency decreased for higher PAHs and with the increase of alkylation. Molecular markers were degraded according to the following sequence: Acyclic isoprenoids < diasteranes < C27 -steranes < ,,-steranes < homohopanes < monoaromatic steranes < triaromatic steranes. Isomeric selectivity was observed within the C1 - and C2 -phenanthrenes, dibenzothiophenes, pyrenes, and chrysenes, providing source and weathering indices for the characterization of the heavy oil spill. Acyclic isoprenoids, C27 -steranes, C1 - and C2 -naphthalenes, phenanthrenes, and dibenzothiophenes were degraded completely when S200 was used. The ratios of the C2 - and C3 -alkyl homologues of fluoranthene/pyrene and chrysene/benzo[a]anthracene are proposed as source ratios in moderately degraded oils. The 4-methylpyrene and 3-methylchrysene were refractory enough to serve as conserved internal markers in assessing the degradation of the aromatic fraction in a manner similar to that of hopane, as used for the aliphatic fraction. [source] Hemiconvulsion,hemiplegia syndrome in a patient with severe myoclonic epilepsy in infancyEPILEPSIA, Issue 9 2009Takafumi Sakakibara Summary We report a 2-year-old girl who had repeated febrile or afebrile seizures since infancy. Prolonged left/right hemiconvulsions and myoclonus of the eyelids/extremities with generalization to tonic,clonic seizures, were refractory to antiepileptic agents. At age 1 year and 4 months, she contracted rotavirus infection, and developed status epilepticus with persistent right hemiclonic seizures. Left unilateral brain edema with subsequent emergence of cortical laminar necrosis and white matter lesions, and progressive atrophy of the left cerebral hemisphere were noted during this period. She showed residual right hemiparesis and mild intellectual disability, and had generalized/eyelid myoclonia and hot water epilepsy after a 5-month seizure-free period. Analysis for SCN1A, the gene encoding the neuronal voltage-gated Na+ channel ,1 subunit revealed a nonsense mutation, R1892X. These indicate the potential risk in patients with severe myoclonic epilepsy in infancy (SMEI) to develop hemiconvulsion,hemiplegia (HH) syndrome. SCN1A mutations may need to be further explored in patients with HH syndrome without features of SMEI. [source] Generalized-onset seizures with secondary focal evolutionEPILEPSIA, Issue 7 2009Randy Williamson Summary The international seizure classification recognizes that partial-onset seizures can become secondarily generalized, but generalized-onset seizures are expected to remain generalized. We report six patients who had recorded seizures with generalized onset, but subsequent evolution into a focal discharge. The clinical seizure onset was generalized absence or myoclonic, and the most common subsequent clinical pattern was prolonged behavioral arrest with mild automatisms, and then postictal confusion. The ictal discharge started with generalized spike-and-wave activity and then acquired a focal predominance. Interictal epileptiform activity was generalized. There were no focal magnetic resonance imaging abnormalities. Four patients were misdiagnosed with complex partial seizures. All patients were initially refractory, but three became seizure-free and three improved after treatment with antiepileptic medications appropriate for absence or myoclonic seizures. Generalized-onset seizures that acquire focal features are easily misdiagnosed as complex partial. These seizures have a more favorable response to medications effective against generalized absence and myoclonic seizures. [source] Automated normalized FLAIR imaging in MRI-negative patients with refractory focal epilepsyEPILEPSIA, Issue 6 2009Niels K. Focke Summary Background:, Patients with focal epilepsy that is refractory to medical treatment are often considered candidates for resective surgery. Magnetic resonance imaging (MRI) has a very important role in the presurgical work-up of these patients, but is unremarkable in about one-third of cases. These patients are often deferred from surgery or have a less positive outcome if surgery is eventually undertaken. The aim of this study was to evaluate our recently described voxel-based technique using routine T2-FLAIR (fluid-attenuated inversion-recovery) scans in MRI-negative patients and to compare the results with video-EEG (electroencephalography) telemetry (VT) findings. Methods:, We identified 70 epilepsy patients with refractory focal seizures who underwent VT and had a normal routine MRI. T2-FLAIR scans were bias-corrected, and intensity and spatially normalized (nFSI) using Statistical Parametric Mapping 5 (SPM5) as previously described. Individual scans were then compared against a set of 25 normal controls using a voxel-based method. Results:, SPM5 identified 10 patients with suprathreshold clusters (14.3%). In 50% of these there was concordance between the lobe of the most significant cluster and the presumed lobe of seizure onset, as defined by VT. All cases were concordant with respect to lateralization of the putative focus. Conclusion:, Using nFSI we identified focal structural cerebral abnormalities in 11.4% of patients with refractory focal seizures, and normal conventional MRI, that were fully or partially concordant with scalp VT. This voxel-based analysis of FLAIR scans, which are widely available, could provide a useful tool in the presurgical evaluation of epilepsy patients. Ongoing work is to compare these imaging findings with the results of intracranial EEG and histology of surgical resections. [source] Molecular and diffusion tensor imaging of epileptic networksEPILEPSIA, Issue 2008Aimee F. Luat Summary Several studies have shown that seizure-induced cellular and molecular changes associated with chronic epilepsy can lead to functional and structural alterations in the brain. Chronic epilepsy, when medically refractory, may be associated with an expansion of the epileptic circuitry to involve complex interactions between cortical and subcortical neuroanatomical substrates. Progress in neuroimaging has led not only to successful identification of epileptic foci for surgical resection, but also to an improved understanding of the functional and microstructural changes in long-standing epilepsy. Positron emission tomography (PET), functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) are all promising tools that can assist in elucidating the underlying pathophysiology in chronic epilepsy. Studies using PET scanning have demonstrated dynamic changes associated with the evolution from acute to chronic intractable epilepsy. Among these changes are data to support the existence of secondary epileptogenesis in humans. MRI with DTI is a powerful tool which has the ability to characterize microstructural abnormalities in epileptic foci, and to demonstrate the white matter fibers and tracts participating in the epileptic network. In this review, we illustrate how PET and DTI can be applied to depict the functional and microstructural alterations associated with chronic epilepsy. [source] |