Hyperhomocysteinemia is associated with deep venous thrombosis of the lower extremities in Tunisian patients

OBJECTIVES: To test the association between hyperhomocysteinemia (HHC) and deep venous thrombosis (DVT) of lower extremities in Tunisians. DESIGN AND METHODS: This case-control study included 90 patients with DVT of the lower extremities and 160 healthy controls. Plasma homocysteine, vitamin B(12) and folate were determined using immunoenzymatic methods. Logistic regression models were performed to test whether the association between HHC and DVT is independent and to precise determinants of HHC in DVT patients. RESULTS: Plasma total homocysteine concentrations were significantly higher in patients with DVT (17.4+/-11.5 micromol/L) and in patients with idiopathic DVT (15.2+/-6.4 micromol/L) as compared to controls (11.5+/-3.3 micromol/L). HHC was significantly associated (p<0.001) with all DVT (OR, 8.82; 95% CI, 3.96-19.6) as well as idiopathic DVT (OR, 7.40; 95% CI, 3.01-10.8). These associations persisted after adjustment for several thrombosis risk factors. In patients with DVT, HHC was related to folate and vitamin B(12) concentrations, but neither to the type of occurrence nor to the recurrence of DVT. CONCLUSION: HHC is independently associated with first DVT of lower extremities in Tunisians. Homocysteine should be assessed in patients with DVT and the effect of vitamin B supplementation should be tested among them.     

Saphenous vein graft-to-left atrium fistula treated with percutaneous transcatheter embolization with coils

Coronary artery fistulae are rare anomalies that are most commonly congenital and rarely acquired. We present a first case of a vein graft to the left atrium fistula that occurred post coronary artery bypass grafting and was treated with percutaneous transcatheter embolization with coiling. The coil was initially lost in the left atrium, but was successfully retrieved and the fistula was closed. We review the pertinent literature on acquired coronary artery fistulae and their management.     

Head and facial injuries due to cluster munitions

Cluster munitions are weapons that scatter smaller sub-munitions intended to kill or mutilate on impact. They have been used by the Israeli army in the south of Lebanon and are now scattered over wide rural areas affecting its inhabitants. Because of their easily “pickable” nature, sub-munitions can inflict injuries to the head and face regions. In this study, we aimed to explore the head and face injuries along with their clinical features in a group of Lebanese patients who suffered from such injuries due to a sub-munition’s detonation. The study included all the cases reported between 14 August 2006 and 15 February 2013, with head and face injuries related to cluster bombs. Injuries were classified into brain, eye, otologic and auditory impairments, oral and maxillofacial, and skin and soft-tissue injuries. Psychological effects of these patients were also examined as for post-traumatic stress disorder, major depressive disorder, generalized anxiety disorder and acute stress syndrome. During the study period, there were 417 casualties as a result of cluster munitions’ blasts. Out of the total number of victims, 29 (7 %) were injured in the head and the face region. The convention on cluster munitions of 2008 should be adhered to, as these inhumane weapons indiscriminately and disproportionately harm innocent civilians, thereby violating the well-established international principles governing conflict and war today.     

Geomechanical behavior of the reservoir and caprock system at the In Salah CO2 storage project

Almost 4 million metric tons of CO₂ were injected at the In Salah CO₂ storage site between 2004 and 2011. Storage integrity at the site is provided by a 950-m-thick caprock that sits above the injection interval. This caprock consists of a number of low-permeability units that work together to limit vertical fluid migration. These are grouped into main caprock units, providing the primary seal, and lower caprock units, providing an additional buffer and some secondary storage capacity. Monitoring observations at the site indirectly suggest that pressure, and probably CO₂, have migrated upward into the lower portion of the caprock. Although there are no indications that the overall storage integrity has been compromised, these observations raise interesting questions about the geomechanical behavior of the system. Several hypotheses have been put forward to explain the measured pressure, seismic, and surface deformation behavior. These include fault leakage, flow through preexisting fractures, and the possibility that injection pressures induced hydraulic fractures. This work evaluates these hypotheses in light of the available data. We suggest that the simplest and most likely explanation for the observations is that a portion of the lower caprock was hydrofractured, although interaction with preexisting fractures may have played a significant role. There are no indications, however, that the overall storage complex has been compromised, and several independent data sets demonstrate that CO₂ is contained in the confinement zone.In Salah is an industrial-scale carbon capture and storage project located in central Algeria. Between 2004 and 2011, 3.8 million metric tons of CO₂ were injected into an anticlinal structure at ∼1,800 m depth. Storage integrity at the site is provided by a massive, 950-m-thick caprock that sits above the injection interval (Fig. 1). It consists of a number of low-permeability units that work together to limit vertical fluid migration. These are grouped into main caprock units, providing the primary seal, and lower caprock units, providing an additional buffer and some secondary storage capacity.Open in a separate windowFig. 1.Stratigraphic column with interval depths at well KB-502. Depth is given as meters of true vertical depth below the rotary table (m TVD brt) of the drilling rig, a common elevation datum in the oil and gas industry.In June 2011, injection operations halted at the site to allow reevaluation of the injection strategy (1). At the time, several monitoring observations suggested that pressure, and probably CO₂, had migrated vertically into the lower portion of the caprock. Although there are no indications that overall storage integrity has been compromised, these observations raise interesting questions about the geomechanical behavior of the reservoir and lower caprock system.Several hypotheses have been put forward by various groups to explain these observations. These include fault leakage, flow through preexisting fractures, or the possibility that injection pressures hydraulically fractured a portion of the lower seal (2–13). In this work, we evaluate these hypotheses in light of the available data. We suggest that the most likely explanation for the observed behavior is that the lower caprock was hydrofractured, although interaction with preexisting fractures may have played a significant role. Previous studies by Bissell and colleagues (4) and Oye and colleagues (8) have shown that injectivity and microseismic data show indications of fracturing behavior, at least in the reservoir and possibly in the overburden. Here, we use well data to constrain the state of stress in the reservoir and lower caprock, providing strong support for the hydrofracture hypothesis.This work also highlights those monitoring and analysis methods that have been most useful for understanding the field behavior, as well as lessons learned and potential improvements. This perspective can guide future carbon storage projects.     

High-density lipoprotein cholesterol as an indicator of liver function and prognosis in noncholestatic cirrhotics.

BACKGROUND AND AIMS: The liver plays a central role in production and degradation of lipoproteins. Declining lipoprotein cholesterol may reflect deteriorating liver function. METHODS: We reviewed the records of 248 veterans with noncholestatic cirrhosis followed in our clinics or referred for liver transplantation between January 1, 1997 and October 31, 2002 (analysis period) and confirmed our findings prospectively in 165 noncholestatic cirrhotic veterans newly referred for liver transplantation between November 1, 2002 and May 1, 2004 (validation period). RESULTS: In the analysis group, albumin, bilirubin, INR, and Model for End-Stage Liver Disease (MELD) score correlated strongly with high-density lipoprotein (HDL) cholesterol, weakly but significantly with total cholesterol and very-low-density lipoprotein cholesterol (VLDL), and poorly with low-density lipoprotein cholesterol (LDL). Transplant-free mortality at 90, 180, and 365 days was 17/201 (8.5%), 19/173 (11.0%), and 38/119 (31.9%), respectively. Death at all 3 time points was associated with significantly lower initial levels of HDL, VLDL, and total cholesterol, but not LDL cholesterol. Of the lipoproteins, HDL was the best predictor of survival at 180 and 365 days (concordance statistics .86+/-.05 and .78+/-.05, respectively). By multivariate logistic regression, HDL cholesterol and MELD score were independent predictors of survival at 6 and 12 months. By Cox regression, HDL cholesterol below 30 mg/dL was associated with 3.4-fold increase in the hazard ratio for cirrhotic death. In the validation period, HDL cholesterol was confirmed to be significantly associated with death or transplantation at 6 or 12 months. CONCLUSIONS: HDL cholesterol in noncholestatic cirrhotic patients is a liver function test and an indicator of prognosis.     

Does Heparin Coating Improve Patency or Reduce Infection of Tunneled Dialysis Catheters?

Background and objectives: Tunneled dialysis catheters are prone to frequent malfunction and infection. Catheter thrombosis occurs despite prophylactic anticoagulant locks. Catheter thrombi may also serve as a nidus for catheter infection, thereby increasing the risk of bacteremia. Thus, heparin coating of catheters may reduce thrombosis and infection. This study evaluated whether heparin-coated hemodialysis catheters have fewer infections or greater cumulative survival than noncoated catheters.Design, setting, participants, & measurements: We retrospectively queried a prospective access database to analyze the outcomes of 175 tunneled dialysis catheters placed in the internal jugular vein, including 89 heparin-coated catheters and 86 noncoated catheters. The primary outcome was cumulative catheter survival, and the secondary outcome was infection-free catheter survival.Results: The two patient groups were similar in demographics and clinical and catheter features. Catheter-related bacteremia occurred less frequently with heparin-coated catheters than with noncoated catheters (34 versus 60%, P < 0.001). Cumulative catheter survival was similar in heparin-coated and noncoated catheters (hazard ratio, 0.87; 95% confidence interval, 0.55 to 1.36; P = 0.53). On multiple variable survival analysis including catheter type, age, sex, diabetes, coronary artery disease, peripheral vascular disease, cerebrovascular disease, catheter location, and previous catheter, only catheter location predicted cumulative catheter survival (hazard ratio, 2.03; 95% CI, 1.27 to 3.25, with the right internal jugular location being the reference group, P = 0.003). The frequency of thrombolytic instillation was 1.8 per 1000 catheter-days in both groups.Conclusions: Heparin coating decreases the frequency of catheter-related bacteremia but does not reduce the frequency of catheter malfunction.The two major complications of hemodialysis catheters are thrombosis and infection (1). To prevent catheter thrombosis, an anticoagulant (heparin or citrate) is instilled into both catheter lumens at the end of each dialysis session (2). When a catheter clots despite the anticoagulant lock, a thrombolytic agent [tissue plasminogen activator (tPA) or urokinase] is instilled into the catheter lumens. If the thrombolytic agent is unable to restore catheter patency, the catheter is exchanged over a guidewire.Because catheter thrombosis occurs despite instillation of an anticoagulant lock solution, an alternative approach is to coat the surface of the catheter with heparin. Preliminary short-term observations suggest that heparin-coated catheters are less thrombogenic than noncoated catheters (3). However, there are no published clinical studies comparing the long-term patency of heparin-coated and noncoated catheters in hemodialysis patients.Bacteremia is the second major complication of dialysis catheters. It arises from the bacterial biofilm that forms on the inner surface of the catheter after its insertion in the central vein (4). Catheter-related bacteremia is treated with systemic antibiotics in conjunction with catheter removal, guidewire catheter exchange, or instillation of an antibiotic lock into the catheter lumen after each dialysis session (1). The intraluminal thrombus acts as a nidus for the catheter biofilm, and in vitro studies have shown decreased adherence of bacteria to heparin-coated catheters compared with noncoated catheters (5). Moreover, two randomized clinical trials in hospitalized patients with short-term, nontunneled central vein catheters found a lower risk of catheter-related bacteremia in patients with heparin-coated catheters (5,6).The goal of this study was to determine whether heparin-coated dialysis catheters reduce the risk of catheter dysfunction and infection compared with noncoated catheters.     

Palatal impression template for a fully edentulous arch during stage I implant placement

It is often desirable to insert a fixed provisional resin restoration at stage II surgery when the implants are uncovered. It satisfies the patient's esthetics, phonetics, and functional demands and helps create a good emergence profile for the healing gingival tissue. This article presents a procedure that enables the clinician to fabricate a full-arch maxillary provisional restoration for a fully edentulous patient, which can be delivered at second-stage surgery at the time of uncovering the implants.(J Prosthet Dent 1997;77:630-2.)