A rapid response magnitude scale for timely assessment of the high frequency seismic radiation.

In this work the scaling of seismic moment (M0) and radiated energy (Er) is investigated for almost 800 earthquakes of the 2016-17 Amatrice-Norcia sequences in Italy, ranging in moment magnitude (Mw) from 2.5 to 6.5. The analysis of the M0-to-Er scaling highlights a breaking of the source self-similarity, with higher stress drops for larger events. Our results show the limitation of using M0, and in turn Mw, to capture the variability of the high frequency ground motion. Since the observed seismicity does not agree with the assumptions on stress drop in the definition of Mw, we exploit the availability of both Er and M0 to modify the definition of Mw and introduce a rapid response magnitude (Mr), which accounts for the dynamic properties of rupture. The new Mr scale allows us to improve the prediction of the earthquake shaking potential, as shown by the reduction of the between-event residuals computed for the peak ground velocity. The procedure we propose is therefore a significant step towards a quick assessment of earthquakes damage potential and timely implementation of emergency plans.

Temporal evolution of a seismic sequence induced by a gas injection in the Eastern coast of Spain.

Induced seismicity associated with energy production is becoming an increasingly important issue worldwide for the hazard it poses to the exposed population and structures. We analyze one of the rare cases of induced seismicity associated with the underwater gas storage operations observed in the Castor platform, located in the Valencia gulf, east Spain, near a complex and important geological structure. In September 2013, some gas injection operations started at Castor, producing a series of seismic events around the reservoir area. The larger magnitude events (up to 4.2) took place some days after the end of the injection, with EMS intensities in coastal towns up to degree III. In this work, the seismic sequence is analyzed with the aim of detecting changes in statistical parameters describing the earthquake occurrence before and after the injection and identifying possible proxies to be used for monitoring the sequence evolution. Moreover, we explore the potential predictability of these statistical parameters which can be used to control the field operations in injection/storage fluid reservoirs. We firstly perform a retrospective approach and next a perspective analysis. We use different techniques for estimating the value of the expected maximum magnitude that can occur due to antropogenic activities in Castor.

Implantation of permanent jugular catheters in patients on regular dialysis treatment: ten years' experience.

Dual-lumen cuffed central venous catheter proved an important alternative vascular access compared to conventional arteriovenous (Cimino-Brescia) shunt in a selected group of patients on regular dialysis treatment. Typically, these catheters are used as bridging access, until fistula or graft is ready for use, or as permanent access when an arteriovenous fistula or graft is not planned (NKF-DOQI). We conducted a prospective study on IJV permanent catheter insertion and its related earlier and long-term complications. From February 1991 to February 2001 we inserted in 124 patients in end stage renal disease 135 cuffed catheters (130 in the right IJV and 5 in the left IJV), 92 of which were Permcath, 27 Vascath, and 16 Ash-Split. We performed the insertion of catheters by puncturing the IJV under ultrasonographic guid-ance in the lower side of the Sedillot triangle and checking the accurate position of the tip by endocavitary electrocardiography (EC-ECG). The duration of catheter use was from 60 to 1460 days, mean 345 days. The actuarial survival rate at 1 year was 82%, at 2 years 56%, at 3 years 42% and at 4 years 20%. The exit site infection and septicemia rates were 5.2 and 2.86 per 1000 catheter days respectively. Catheter sepsis was implicated in the death of three patients, all of whom had multiple medical problems. Several episodes of thrombosis (6% of dialyses) occurred which required urokinase treatment, and catheter replacement in 12 patients (9.6%). In 3 cases the catheters were displaced and correct repositioning was performed. Two catheters (Ash-Split) were replaced due to accidental damage of the external portion of catheters (alcoholic disinfectant). Catheter tip embolism occurred on one occasion during elective catheter exchange over guide-wire. One of the common problems encountered with cuffed tunneled catheters is poor blood flow, most often secondary to the formation of a fibrin sheath around the lumen. Even if we conducted a non-randomized study, in our experience, the higher rate of malfunctioning catheters was in the group with no anticoagulation therapy. Therefore, we suggest anticoagulation treatment in all patients wearing central vascular catheters with no contraindication. Just one year ago, we followed NKF-DOQI clinical practice guidelines for vascular access that indicated that for patients who have a primary AV fistula maturing, but need im-mediate hemodialysis, tunneled cuffed catheters are the access of choice and the preferred insertion site is the right IJV. Considering recent reports of permanent central venous stenosis or occlusion after IJV can-nulation, currently, our first choice is femoral vein cannulation with smooth silicone rubber catheters, tunneled if long-term utilization is needed (more the 3-4 weeks). In our opinion, the right IJV puncture is to be avoided as much as the venipuncture of arm veins suitable for vascular access placement, particularly the cephalic vein of the non-dominant arm. Our data confirm that permanent venous catheters might rep-resent an effective long-term vascular access for chronic hemodialysis, particularly for older patients with cardiovascular disease and for cancer patients.

The placement of central venous catheters in hemodialysis: role of the endocavitary electrocardiographic trace. Case reports and literature review.

At present, the placement of a central venous catheter is becoming more and more a routine procedure nevertheless it involves different operators in fields such as oncology, nutrition, nephrology, and emergency medicine. It is well known that complications in the placement of CVC may occur in up to 20% of cases. One fifth of the catheters may result to be misplaced either in the internal omolateral jugular vein or in the innominate vein or in the controlateral brachiocephalic veins and usually a chest radiogram is necessary to evaluate its location. On the basis of 10 years of experience including more than 1,000 CVC placements, we now believe that endocavitary electrocardiography EC-ECG, initially studied and applied by Dr. Serafini, constitutes the best technique, more secure and more comfortable for the patient, to verify the position of the tip of a CVC. The technique EC-ECG, very simple and secure, utilizes the CVC as an endocavitary electrode. This is connected to a standard electrocardiograph, the same one to which the patient is connected during the placement of the CVC, and provides, in derivation V 1 or D 3 , an electrocardiographic pattern extremely sensitive to the position of the catheter tip. From December 1991 to December 2000, this technique has been used successfully in our departments of nephrology and applied to 1,139 patients that needed a CVC for hemodialysis. EC-ECG and a standard chest radiogram controlled the first 100 CVC we placed and in the other 1,039 cases, the control was made by EC-ECG alone. Only in 31 patients (2.7% of all cases), due to arrhythmia, the technique EC-ECG was not utilized. According to our experience, the procedure EC-ECG is an extremely reliable technique, sensitive and specific in 100% of cases, easy for the operator to perform, comfortable for patient. It doesn't need additional time to be performed and eliminates the need of taking a chest radiogram that up to now was considered indispensable in order to verify the position of the catheter tip. In this manner serious complications such as pneumothorax, and haemothorax that can complicate the placement of a CVC can also be avoided. Based on our experience, we now believe that this technique, that today has a large application in nephrology, oncology, clinical nutrition and in various branches of general medicine whenever the placement of a CVC is required, should be considered as a possible new guide line in controlling the placement of a CVC together with a chest X-ray when it is necessary.

Strategy to detect and identify Bartonella species in routine clinical laboratory yields Bartonella henselae from human immunodeficiency virus-positive patient and unique Bartonella strain from his cat.

We wished to develop a cost-effective, rapid strategy to detect and identify Bartonella species in the clinical laboratory and to determine the prevalence of Bartonella infection in the Houston veteran population. Bartonella colonies were identified by colony morphology, Gram stain, RapID ANA, repetitive extragenic palindromic-PCR (REP-PCR) and whole-cell fatty acid (CFA) analysis, and these methods were compared for their usefulness. A new test order for "Rochalimaea culture" (the genus Bartonella was previously known as the genus Rochalimaea) was instituted, and in addition, all blood specimens submitted for fungal culture (obtained in an isolator tube) were processed for Bartonella culture. Over a 16-month period we isolated Bartonella henselae from only 0.4% (2 of 533) of total cultures but from 1% (2 of 204) of human immunodeficiency virus-positive patients. After sufficient growth, identification of the Bartonella isolates to the species level could be obtained in 2 days. The REP-PCR allowed discrimination of all known species, whereas CFA analysis distinguished all except B. henselae and Bartonella quintana. The RapID ANA results failed to differentiate between B. henselae and B. quintana, and results for other species differed by only one or two tests. Blood obtained from a kitten which had been introduced into the household of one patient 2 months before the onset of fever yielded a Bartonella strain which was shown to be different from the strain from the patient and distinct from other Bartonella species by a combination of REP-PCR, CFA, and growth characteristics. Subsequent analysis of the citrate synthase gene sequence showed only an 86% similarity with any of the other known Bartonella species, suggesting that this isolate represents a distinct, previously uncharacterized species of Bartonella.

IgA nephropathy associated with Takayasu's arteritis: report of a case and review of the literature.

We report the case of a patient with Takayasu's arteritis, nephrotic syndrome, and pANCA. The kidney biopsy specimen showed the classic features of IgA nephropathy. The course of this patient supports the view that the glomerular and vasculitic involvements of Takayasu's arteritis may result from a common immunologic mechanism, and cases with urinary abnormalities should be carefully followed for the possible coexistence of glomerulonephritis.