In 1974, artificial reef researchers organized the first International Conference on the subject of ‘Reefs’. The conference was held 20–22 March 1974 in Houston, Texas, USA ‘…to provide an ...international forum for the exchange of information, experiences and thoughts among persons involved with or interested in any aspect of artificial reef research, construction or use’ (Proceedings of the International Conference on Artificial Reefs, Houston, 1974, Texas A & M University Sea Grant College, College Station, TX). Nearly forty years have passed since that initial meeting and, while there have been many other conferences held on the subject of artificial reefs (see Bortone 2011a for a partial review), the need for these fora continues. Over the years, there have been changes in approaches, technology, political climate, and financial conditions with regard to artificial reef research. Stone et al. () and Bortone () presented summaries of the previous CARAHs. The purpose here is to emphasize the milestones with regard to technology, direction, emphasis, scope and accomplishment of the efforts of the international artificial reef research community. It is through this perspective that one should gain an appreciation of the overall contribution that CARAHs have made toward refinement and progression to resolve many of the issues we face today in modern aquatic resource management. The continuing level of involvement occurs in the absence of a formal society, standing organizing committee, or scientific tribunal to oversee its progress. The fact that these conferences have occurred with such frequency, orderly direction, and high standards is attributable to the professionalism and diligence of all involved.
The aim of this retrospective study is to investigate efficacy and middle-term results of the stent graft treatment for diseases of descending thoracic aorta.
From March 1999 to October 2003, 132 ...patients (113 male and 19 female, mean age 62+/-14 years) were enrolled. They were divided into 4 groups: aneurysms (43, group A), post-traumatic lesions (24, group B), and complicated type B dissections (43, group C). Twenty-two further patients, with chronic type B dissection and not suitable for endovascular or surgical or hybrid techniques because of multiple entry tears without difference between the true and false lumen and poor clinical conditions, were obliged to receive medical management only (group D). All patients underwent computed tomography (CT) scan and angiography as preoperative assessment. An optimal deployment with exclusion of the aneurysm and/or closure of the entry tear in dissection was achieved in 96.4% (106/110) of the patients that were discharged in good conditions within 6 days. No spinal cord injuries were observed. The follow-up (average 20.82+/-10.01 months, range 1 to 55 months), performed with serial chest CT scans, was 100% complete. No stent graft-related complications were detected, although only in 1 case, an asymptomatic rupture of the Excluder connecting bar was found with a perforation of the fabric and an intra-aortic exposition of the bar itself. In 2 patients with chronic dissection an asymptomatic type II endoleak was detected. A total of 4 hospital deaths resulted in an overall operative mortality of 3.9%. Seven patients (6.3%) died during the follow-up 5 of them for other diseases (4.5%). However, a 40.9% mortality was observed within the obliged medical treatment group.
Endovascular treatment of thoracic aortic diseases, even in the acute phase, may represent a valid option with a low mortality rate. Moreover, the efficacy is proved in the middle-term whereas the long-term follow-up is still pending.
Objective: Assessment of endovascular stent-graft treatment for diseases of the descending thoracic aorta as a valid and effective alternative to surgery. Methods: From March 1999 to August 2000, a ...total of 16 patients underwent deployment of endovascular stent-grafts in the descending thoracic aorta. Patients were divided into three groups according to the type of lesion. Group A (n=8) included five patients with atherosclerotic aneurysm and three with chronic post-traumatic pseudoaneurysm. Patients with acute post-traumatic pseudoaneurysm (n=3) and type B aortic dissection (n=5) were included in Groups B and C, respectively. All patients underwent 5-mm chest spiral angio-computerized tomography (CT) scan and angiography as preoperative assessment. The deployed stent-graft systems were Talent™-Medtronic and Excluder®-Gore. Results: A total of 20 stent-grafts were placed. Two patients required deployment of two grafts, while three grafts were juxtaposed in a third patient in order to treat larger lesions. There was no mortality related to the procedure, although one patient (6.2%) died because of multiorgan failure 24 h post-operatively. The placement of the graft was successful in all cases except one affected with type B dissection and characterized by a very large intimal flap, which was eventually fenestrated by graft guidewire. Therefore, an optimal sealing of the grafts was achieved in 15 patients. However, in one patient the descending aorta had to be surgically replaced because of the calcified pseudoaneurysm still compressing the trachea and left bronchus. Two patients required a left carotid-subclavian by-pass in order to achieve a sufficient neck for the proximal placement of the graft. No spinal cord injuries were observed. At the follow-up, performed with chest spiral angio-CT scan within 72 h and scheduled at 6 and 12 months and once a year, no stent-graft related complications have been detected. Conclusions: Endoluminal stent-graft treatment may represent a valid option in well-selected cases of descending thoracic aorta diseases. A longer follow-up in a larger series of patients is desirable to confirm these initial positive results.
In a relatively short time, artificial reef researchers have established a rich and valuable archive of information from which to build future research programs. The personal interactions and dialog ...essential for the development of "good science" has been established and continues.
Ongoing studies have increased in rigor and professionalism while building on ecological theory. Artificial reef research is becoming more sophisticated from a technical perspective, but needs to address the inherent problems in working in a "boundless" environment that often is impacted by
human interference. With the incorporation of information from other disciplines, improvements are expected in overall approaches when attempting to answer several fundamental questions. To facilitate this improving trend, adequate funding resources will be essential. Concomitantly, study
designs that incorporate large-scale and long-term approaches, when coupled with multi-jurisdictional cooperation, will eventually allow a full assessment of the potential benefits artificial reefs may have toward achieving fisheries management objectives.
Although hurricane disturbance is a natural occurrence in mangrove forests, the effect of widespread human alterations on the resiliency of estuarine habitats is unknown. The resiliency of mangrove ...forests in southwest Florida to the 2004 hurricane season was evaluated by determining the immediate response of mangroves to a catastrophic hurricane in areas with restricted and unrestricted tidal connections. The landfall of Hurricane Charley, a category 4 storm, left pronounced disturbances to mangrove forests on southwest Florida barrier islands. A significant and negative relationship between canopy loss and distance from the eyewall was observed. While a species-specific response to the hurricane was expected, no significant differences were found among species in the size of severely impacted trees. In the region farthest from the eyewall, increases in canopy density indicated that refoliation and recovery occurred relatively quickly. There were no increases or decreases in canopy density in regions closer to the eyewall where there were complete losses of crown structures. In pre-hurricane surveys, plots located in areas of management concern (i.e., restricted connection) had significantly lower stem diameter at breast height and higher stem densities than plots with unrestricted connection. These differences partially dictated the severity of effect from the hurricane. There were also significantly lower red mangrove (Rhizophora mangle) seedling densities in plots with restricted connections. These observations suggest that delays in forest recovery are possible in severely impacted areas if either the delivery of propagules or the production of seedlings is reduced by habitat fragmentation.
Environmentally induced intersexuality among natural populations of poeciliids was first described by Howell et al. (1980). In two paper mill effluent-receiving streams, the Fenholloway River, Taylor ...Co. and Elevenmile Creek, Escambia Co., Florida, the anal-fins of females of the mosquitofish Gambusia holbrooki) were modified into gonopodium-like structures typical of developing males. Where present, females of two other poeciliids, the least killifish (Heterandria formosa) and the sailfin molly (Poecilia latipinna) also bore similarly modified anal-fins. Masculinization (arrhenoidy) in response to paper mill effluent was subsequently reproduced in controlled exposures using mosquitofish females (Drysdale and Bortone 1989). Although a number of mechanisms of endocrine-disruption, focusing on the presence in effluent of chemicals with steroidal properties have been proposed (Howell et al. 1980; Davis and Bortone 1992) the complex nature of paper mill effluents has made the task of identifying masculinizing chemicals difficult. In controlled exposures, female mosquitofish exposed to the plant sterol, beta -Sitosterol, a major byproduct of wood-pulp delignification, in the presence of Mycobacterium smegmatis became masculinized (Howell and Denton 1989). McLatchy and Van Der Kraak (1995) provided evidence that exposure to beta -Sitosterol reduced gonadal steroid synthesis in goldfish. Mycobacterium smegmatis and plant sterols (including beta -Sitosterol) are present in waters unimpacted by paper mill effluents, albeit at much lower concentrations.
Hereditary Haemorrhagic Teleangiectasia (HHT) is a vascular disorder of angiogenesis transmitted in an autosomal dominant pattern, characterised by heterogeneity in clinical manifestations. One of ...the most important organ involved is lung, including pulmonary arteriovenous malformations (PAVM). PAVM occur in 20 to 30% of the HHT population and recently are considered a marker of disease. PAVM are direct artery-to-vein connections with low pressure and without an interveining capillary bed. PAVM are classified as simple (supplied by one feeding artery) or complex (receiving blood supply from two or more feeding artery). According to the international reports, treatment it's recommendable for all PAVM with feeding vessels 3mm or larger, in order to reduce the risk of cerebral ischaemia and neurologic manifestations frequently attributed to paradoxical embolisation. Transcatheter embolotherapy of PAVM is a form of treatment based on occlusion of the feeding artery to a PAVM by using platinum coils or detachable balloons. The technique of coil embolisation involves the exact localisation of PAVM by pulmonary angiography followed by superselective percutaneous caheterisation of feeding artery obtained by using a dedicated 7F guiding catheter, which coaxially allocates a 5F hydrophilic catheter advanced in order to perform both superselective angiography of feeding artery and embolisation itself. Inside the 5F catheter the platinum coils are advanced using a .035'' guide-wire and released until an optimal occlusion of feeding artery is achieved. At the end of the procedure angiographic control is performed in order to verify the occlusion of feeding artery. The use of platinum coils is preferable over detachable balloons when feeding artery are greater than 7 mm in diameter and have irregular anatomical configuration. On the other hand, the principal advantage of using detachable balloons is that the balloon itself can be deflated and repositioned if necessary. Transcatheter embolotherapy is technically safe and clinically effective and may represent the primary choice of treatment in HHT patients. On the other hand the most common complications of this treatment (pleurisy and air embolism) can be prevented by using some tips during the embolisation procedure like "anchor technique," "scaffold technique" and "balloon assisted technique." Cerebral arteriovenous malformations (CAVM) are present in 10-20% of patients with HHT and multiple in 50% of cases. Cortical surface is the most frequent localisation. Angiography is needed to diagnose all CAVM and to clarify the angioarchitecture of the lesion. In HHT CAVM are usually either micro-AVM, with a nidus not bigger than 1 cm, or small AVM, with a nidus between 1 and 3 cm. Quite frequently there are lesions characterised by arteriovenous fistulas. In the three patterns of CAVM usually found in HHT, small AVM are the most risky for bleeding although the risk is lower than that associated with sporadic ones. It is estimated from 0.38 to 0.69% per year in spite of the general incidence of bleeding in sporadic CAVM that ranges from 2 to 4% per year. In HHT patients, at present, the precise indications and timing of treatment are not established. Trend is to treat small AVM and AVF and to follow-up micro-AVM with MRI and angiography. As for sporadic CAVM, treatment of small AVM is usually referred to stereotactic radiosurgery. Endovascular embolisation is proposable if the lesion is easily reachable by microcatheterism and the position of the microcatheter is safe. Glue is used for embolisation and the technique is briefly discussed.
BACKGROUND: Stent grafting has been reported as a viable therapeutic option for the delayed treatment of traumatic rupture of the aortic isthmus as well as reconstruction of thoracic aortic ...dissections. We tested the hypothesis of whether immediate endovascular management offers clinical and pathological advantages over a delayed approach in patients with post-traumatic aortic pseudoaneurysms (PAPs) and Stanford type-B dissections (TBDs). METHODS: Thirty-one consecutive patients who were admitted with diagnosis of either PAP (n=10; 33.4+/-8.7 years) or TBD (n=21; 58.2+/-8.4 years) were respectively divided into 2 groups according to the timing of diagnosis and endovascular treatment after the traumatic or pathologic event: immediate (lteq2 weeks; PAP=6 and TBD=7) and delayed (>2 weeks; PAP=4 and TBD=14). Excluder-Gore (11 in PAP and 8 in TBD) and Talent-Medtronic (1 in PAP and 7 in TBD) endovascular stent grafts were deployed. Follow-up was performed at 3 months, 6 months, and 1 year and based on laboratory tests; chest angio-computed tomography scans of chest, abdomen, and pelvis; and transesophageal echocardiography. RESULTS: The endovascular procedure proved uneventful in all PAP patients who underwent either immediate or delayed treatment. In 1 PAP patient with delayed treatment, surgical removal of the pseudoaneurysm was still necessary because of further compression of the airway stem. All immediately treated TBD patients were also successful. However, in 8 of 13 TBD patients with delayed treatment (61.5%), a stent graft deployment was not possible because of complicated progression of the false lumen and multiple intimal entry tears: 1 patient benefited by fenestrations of the false lumen and 7 patients underwent medical therapy. One patient (8.3%) died because of retrograde dissection involving the aortic arch. All patients treated with endovascular stent grafts were discharged within 5 days. CONCLUSIONS: An immediate endovascular management of PAP and TBD patients offers important advantages such as avoidance of high-risk surgical procedures and postoperative complications with short hospital stay. Moreover, it has been observed that an immediate endovascular treatment allows a safe management of all patients with complete healing of the aortic wall and regression of the pseudoaneurysm in the PAP group and thrombosis of the false lumen in TBD patients.
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