Resilient biotic response to long-term climate change in the Adriatic Sea

Preserving adaptive capacities of coastal ecosystems, which are currently facing the ongoing climate warming and a multitude of other anthropogenic impacts, requires an understanding of long-term biotic dynamics in the context of major environmental shifts prior to human disturbances. We quantified responses of nearshore mollusk assemblages to long-term climate and sea-level changes using 223 samples (~71,300 specimens) retrieved from latest Quaternary sediment cores of the Adriatic coastal systems. These cores provide a rare chance to study coastal systems that existed during glacial lowstands. The fossil mollusk record indicates that nearshore assemblages of the penultimate interglacial (Late Pleistocene) shifted in their faunal composition during the subsequent ice age, and then reassembled again with the return of interglacial climate in the Holocene. These shifts point to a climate-driven habitat filtering modulated by dispersal processes. The resilient, rather than persistent or stochastic, response of the mollusk assemblages to long-term environmental changes over at least 125 thousand years highlights the historically unprecedented nature of the ongoing anthropogenic stressors (e.g., pollution, eutrophication, bottom trawling, and invasive species) that are currently shifting coastal regions into novel system states far outside the range of natural variability archived in the fossil record.

Climate variation during the Holocene influenced the skeletal properties of Chamelea gallina shells in the North Adriatic Sea (Italy)

Understanding how marine taxa will respond to near-future climate changes is one of the main challenges for management of coastal ecosystem services. Ecological studies that investigate relationships between the environment and shell properties of commercially important marine species are commonly restricted to latitudinal gradients or small-scale laboratory experiments. This paper aimed to explore the variations in shell features and growth of the edible bivalve Chamelea gallina from the Holocene sedimentary succession to present-day thanatocoenosis of the Po Plain-Adriatic Sea system (Italy). Comparing the Holocene sub-fossil record to modern thanatocoenoses allowed obtaining an insight of shell variations dynamics on a millennial temporal scale. Five shoreface-related assemblages rich in C. gallina were considered: two from the Middle Holocene, when regional sea surface temperatures were higher than today, representing a possible analogue for the near-future global warming, one from the Late Holocene and two from the present-day. We investigated shell biometry and skeletal properties in relation to the valve length of C. gallina. Juveniles were found to be more porous than adults in all horizons. This suggested that C. gallina promoted an accelerated shell accretion with a higher porosity and lower density at the expense of mechanically fragile shells. A positive correlation between sea surface temperature and both micro-density and bulk density were found, with modern specimens being less dense, likely due to lower aragonite saturation state at lower temperature, which could ultimately increase the energetic costs of shell formation. Since no variation was observed in shell CaCO₃ polymorphism (100% aragonite) or in compositional parameters among the analyzed horizons, the observed dynamics in skeletal parameters are likely not driven by a diagenetic recrystallization of the shell mineral phase. This study contributes to understand the response of C. gallina to climate-driven environmental shifts and offers insights for assessing anthropogenic impacts on this economic relevant species.

Numerous new records of tropical non-indigenous species in the Eastern Mediterranean highlight the challenges of their recognition and identification

New data on 52 non-indigenous mollusks in the Eastern Mediterranean Sea is reported. Fossarus sp. (aff.aptus sensu Blatterer 2019), Coriophoralessepsiana Albano, Bakker & Sabelli, sp. nov., Cerithiopsissp. aff.pulvis, Joculatorproblematicus Albano & Steger, sp. nov., Cerithiopsis sp., Elachisina sp., Iravadiaaff.elongata, Vitrinella aff. Vitrinella sp. 1 (sensu Blatterer 2019), Melanellaorientalis, Parviorisaff.dilecta, Odostomiacf.dalli, Oscillavirginiae, Partheninacossmanni, Partheninatypica, Pyrgulinacraticulata, Turbonillafuniculata, Cylichnacollyra, Musculuscoenobitus, Musculusaff.viridulus, Chavaniaerythraea, Scintillacf.violescens, Iacraseychellarum and Corbulaerythraeensis are new records for the Mediterranean. An unidentified gastropod, Skeneidae indet., Triphora sp., Hypermastus sp., Sticteulima sp., Vitreolinacf.philippi, Odostomia (s.l.) sp. 1, Henrya (?) sp., and Semelidae sp. are further potential new non-indigenous species although their status should be confirmed upon final taxonomic assessment. Additionally, the status of Dikolepsmicalii, Hemiliostracaclandestinacomb. nov. and H.athenamariaecomb. nov. is changed to non-indigenous, range extensions for nine species and the occurrence of living individuals for species previously recorded from empty shells only are reported. Opimaphorablattereri Albano, Bakker & Sabelli, sp. nov. is described from the Red Sea for comparison with the morphologically similar C.lessepsiana Albano, Bakker & Sabelli, sp. nov. The taxonomic part is followed by a discussion on how intensive fieldwork and cooperation among institutions and individuals enabled such a massive report, and how the poor taxonomic knowledge of the Indo-Pacific fauna hampers non-indigenous species detection and identification. Finally, the hypothesis that the simultaneous analysis of quantitative benthic death assemblages can support the assignment of non-indigenous status to taxonomically undetermined species is discussed.

Low diversity or poorly explored? Mesophotic molluscs highlight undersampling in the Eastern Mediterranean

Mesophotic assemblages are the next frontier of marine exploration in the Mediterranean Sea. Located below recreational scuba diving depths, they are difficult to access but host a diverse array of habitats structured by large invertebrate species. The Eastern Mediterranean has been much less explored than the western part of the basin and its mesophotic habitats are virtually unknown. We here describe two mesophotic (77-92 m depth) molluscan assemblages at a rocky reef and on a soft substrate off northern Israel. We record 172 species, of which 43 (25%) are first records for Israel and increase its overall marine molluscan diversity by 7%. Only five of these species have been reported in recent surveys of the nearby Lebanon, suggesting that our results are robust at a broader scale than our study area and that the reported west-to-east declining diversity gradient in the Mediterranean needs a reappraisal based on proper sampling of the eastern basin. We found only four (2%) non-indigenous species, represented by seven (0.5%) specimens. These results suggest that pristine native assemblages still thrive at this depth in Israel, in contrast to the shallow subtidal heavily affected by global warming and biological invasions, calling for strong conservation actions for these valuable but vulnerable habitats.

Stratigraphic signatures of mass extinctions: ecological and sedimentary determinants

Stratigraphic patterns of last occurrences (LOs) of fossil taxa potentially fingerprint mass extinctions and delineate rates and geometries of those events. Although empirical studies of mass extinctions recognize that random sampling causes LOs to occur earlier than the time of extinction (Signor–Lipps effect), sequence stratigraphic controls on the position of LOs are rarely considered. By tracing stratigraphic ranges of extant mollusc species preserved in the Holocene succession of the Po coastal plain (Italy), we demonstrated that, if mass extinction took place today, complex but entirely false extinction patterns would be recorded regionally due to shifts in local community composition and non-random variation in the abundance of skeletal remains, both controlled by relative sea-level changes. Consequently, rather than following an apparent gradual pattern expected from the Signor–Lipps effect, LOs concentrated within intervals of stratigraphic condensation and strong facies shifts mimicking sudden extinction pulses. Methods assuming uniform recovery potential of fossils falsely supported stepwise extinction patterns among studied species and systematically underestimated their stratigraphic ranges. Such effects of stratigraphic architecture, co-produced by ecological, sedimentary and taphonomic processes, can easily confound interpretations of the timing, duration and selectivity of mass extinction events. Our results highlight the necessity of accounting for palaeoenvironmental and sequence stratigraphic context when inferring extinction dynamics from the fossil record.

Early-Middle Pleistocene benthic turnover and oxygen isotope stratigraphy from the Central Mediterranean (Valle di Manche, Crotone Basin, Italy): Data and trends

Ostracod faunal turnover and oxygen isotope data (foraminifera) along the Valle di Manche (VdM) section are herein compiled. Specifically, the material reported in this work includes quantitative palaeoecological data and patterns of ostracod fauna framed within a high-resolution oxygen isotope stratigraphy (δ¹⁸O) from Uvigerina peregrina. In addition, the multivariate ostracod faunal stratigraphic trend (nMDS axis-1 sample score) is calibrated using bathymetric distributions of extant molluscs sampled from the same stratigraphic intervals along the VdM section. Data and analyses support the research article “Dynamics of benthic marine communities across the Early-Middle Pleistocene boundary in the Mediterranean region (Valle di Manche, Southern Italy): biotic and stratigraphic implications” Rossi et al. [1].

Neuropathy as the only symptom of common carotid artery spontaneous rupture. Case report

We describe a case of a false aneurysm of the common carotid artery, caused by spontaneous carotid rupture, with atypical clinical presentation. The patient came to the our Hospital complaining of left shoulder pain and functional impairment of her left arm, during the past 20 days. The diagnostic work-up, color Doppler ultrasound, MR and angiography, evidenced a cervical false aneurysm; the electromyography showed denervation of the deltoid muscle, caused by cervical nerve roots compression. The therapeutic stages were initially an endovascular stent placement; then a surgical stage with evacuation for the hematoma and reconstruction of the carotid artery with saphenous graft.

Symptomatic subtotal occlusion of the innominate artery treated with balloon angioplasty and stenting

PURPOSE

To report the endovascular treatment of a subtotal occlusion of the innominate artery giving rise to subclavian steal syndrome.

METHODS AND RESULTS

A 60-year-old man in general good health was admitted to the hospital for sudden onset of amaurosis in the right eye. Thrombosis of the central retinal artery was diagnosed. Physical examination, color flow duplex imaging, and aortic arch angiography showed a subtotal occlusion of the innominate artery with right subclavian steal syndrome. One month later, balloon dilation and stenting of the innominate artery was performed through a right axillary access without cerebral protection. The innominate artery was recanalized with correction of the steal syndrome and restoration of the right radial pulse; no complications occurred. Twelve months later, color flow duplex sonography confirmed innominate stent patency and antegrade flow in the right vertebral artery.

CONCLUSIONS

Our experience supports the view that percutaneous endovascular techniques are appropriate and are the preferred treatment for lesions of the supra-aortic vessels. Continued surveillance will determine their long-term durability.

[Infected aneurysms of the abdominal aorta. Personal case reports]

Two cases of infected aneurysms of the subrenal abdominal aorta observed in the last year are reported. In this study some specific aspects of this unusual pathology are analyzed: the high mortality rate, the difficulties involved in the diagnosis and the surgical solutions.

[Consumption coagulopathy associated with a case of an abdominal aortic aneurysm]

Consumption coagulopathy with clinical symptoms reveals aortic arterial aneurysms in less than 5% of cases. The authors report a case of abdominal aortic aneurysm: surgical repair is able to remove the hemostasis abnormalities for a long time. Implications of the consumption coagulopathy are analyzed: diagnosis, preoperative correction of the coagulopathy, surgical technique.

Clinical, electrocardiographic, and echocardiographic features in patients with asymptomatic aortic abdominal aneurysm

Cardiac involvement in peripheral vascular diseases can present interesting patho-physiological aspects and can influence the prognosis. The authors evaluated the cardiac condition of patients with asymptomatic aortic abdominal aneurysm (AAAA) by using clinical, electrocardiographic, and echocardiographic techniques. Seventy-eight patients were studied, 74 men and 4 women, with ages ranging from fifty-five to eighty-one years (mean 69.5 +/- 6.4). All patients were submitted to a complete clinical examination, usual blood tests, a 12-lead resting electrocardiogram, and an echo-Doppler evaluation. Forty-eight subjects (61.5%) were affected by hypertension, 53 (67.9%) were smokers, 25 (32.1%) were alcohol abusers, 39 (50%) had a history of angina pectoris, 20 (25.6%) had had previous myocardial infarction, and 30 (38.5%) were receiving active cardiovascular treatment. All patients except 2, who had chronic atrial fibrillation, manifested sinus rhythm. Electrocardiographic signs of left ventricular (LV) hypertrophy were present in 20 cases (25.6%), intraventricular conduction disturbances in 19 (24.4%), pathological Q waves in 20 (25.6%), and primary repolarization abnormalities in 25 (32.1%). Echocardiography showed a slight increase in left atrial diameter and intraventricular septum thickness (41.5 +/- 4.3 and 12.3 +/- 2 mm respectively). A clearer increase was found in LV mass index (159 +/- 44 g/m2). In 31 patients one or more LV asynergic segments were found. In our patients with AAAA the prevalence of major risk factors for atherosclerosis and ischemic heart disease including previous myocardial infarction was high. Echo-derived LV myocardial mass index was higher than normal even though electrocardiographic criteria for LV hypertrophy did not match echocardiographic data in all subjects. Finally a moderate prevalence of intraventricular conduction disturbances was recorded.

[Pseudo-occlusions of the internal carotid artery]

The pseudo-occlusion (P.O.) of the internal carotid artery is defined as an atheromatous lesion causing a high-grade stenosis, which describes a peculiar angiographic finding ("string sing" or "slim sign"). The authors report their experience with 6 P.O. (angiographically diagnosed) that had been found in 16 months. In all these cases, whenever there was a clinical e/or B-scan ultrasound suspect, angiographic recommendations for the detection of that lesion have been applied. One of these 6 patients, clinically asymptomatic, refused surgery, remaining asymptomatic for cerebral ischemia during the successive 16 months; angiographic control evidenced an unmodified P.O. The other 5 patients, clinically symptomatic, underwent surgical correction: in one, intraoperative finding was a total carotid occlusion. In the other 4 patients the P.O. was confirmed and an endoarterectomy has been done. No immediate or later complications have been noted (clinical and ultrasonographic average follow-up time was 12 months). The experience described by the authors leeds to some considerations: a) the carotid P.O. is not so rare; specially if adequate angiographic technique has been employed; b) the non-invasive studies could not reliably distinguish a P.O; c) intraoperative findings do not confirm, always, angiographic ones but a fibrous, chronic and totally occluded internal carotid artery; d) the evolution of P.O. in a complete carotid occlusion is very probable but not obligatory, and if this happens it needs long period of time; consequently the surgical correction of P.O. could be justified but not urgently; e) the surgical correction of the P.O. can be done without particular difficulty and its outcome is so similar to those obtained from the routine carotid surgery.

Hepatic artery aneurysm: an ever present danger

Hepatic artery aneurysms are infrequent vascular lesions, difficult to diagnose preoperatively manifesting themselves usually by acute rupture. We report our experience in both diagnosis and surgical treatment of 3 cases. The selective angiograph of the celiac tripod and of superior mesenteric artery, is an indispensable means able, not only to put forward a certain diagnosis, but also to supply precious notions on the possibilities of compensation on the side of the collateral circle and of consequence, to suggest operative tactics. Surgical management may range from the simple binding to the reconstruction of the hepatic arterial axis by means of prosthesis grafts and if possible to the simple excision and termino-terminal regraft.

[Reinterventions for arterial reconstruction in anastomotic aneurysm]

We reviewed our experience on the surgical treatment of anastomotic false aneurysms from 1979 through 1990: two groups of patients were identified. Group 1 (31 patients) included patients who had been previously operated on at our Institute and then routinely followed-up with physical examination and ultrasonographic studies. The incidence of anastomotic aneurysm in this group was 4.03%; the interval between insertion of the prosthesis and detection of the false aneurysm varied from 5 to 144 months, with a median interval of 58 month. The surgical treatment of choice (false aneurysm resection and graft interposition) has been successfully performed (97% of cases) without mortality. Group 2 (8 patients) included patients with complications of false aneurysm (emergency operations); in this group radical treatment was not always applicable; mortality and amputations rate were significantly increased (respectively 25% and 37%). We conclude that, after prosthetic reconstructions, only a careful long-term follow-up (also with use of ultrasonic and/or CT-scan studies) may allow reduction in morbidity and improvement in late survival.

[A subclavian vein lesion due to the positioning of a chest tube via thoracostomy]

The authors describe an unusual complication of chest tube placement: subclavian vein lesion. After a literature review concerning complications of chest tube placement, the authors conclude that associated risks may be best minimized with a strict adherence to standardized technique and management protocol.

[Recanalization with laser and angioplasty of atherosclerotic lesions of the legs. Personal experience with 31 treated lesions]

From January to November 1989, 31 iliac and femoro-popliteal atherosclerotic lesions were treated in 29 patients (age range: 33-80 years) by means of percutaneous laser-assisted angioplasty. The lesions were 6 iliac tubular stenoses, 6 iliac occlusions and 19 femoro-popliteal occlusions, 2-20 cm long. The laser equipment employed was in 10 cases a Cardiolase 4000 Nd:YAG "hot tip" unit, and in 21 cases a Nd:YAG "sapphire contact probe" unit. Initial success was achieved in 23/31 lesions (74%); the follow-up, by clinical examination, Doppler US, and ankle-arm pressure index performed every 4th month, showed 1-year actuarial patency of 80% for femoro-popliteal occlusion and 100% for iliac lesion, with 87% cumulative patency. Overall complication rate was 22.5%. There were 6 local complications, 4 of which were hematomas at the arterial puncture site, and 2 were performation of the superficial femoral artery, all without any clinical sequelae; one patient developed rethrombosis within 72 hours from treatment, which needed amputation after an emergency bypass. Our preliminary results show no significant improvement when compared with conventional balloon angioplasty results both in immediate success rate and in short-to-midterm patency; furthermore, laser therapy was burdened by a higher complication rate. We believe that laser angioplasty should be employed only in arterial occlusion uncrossable with angiographic guidance alone.

[An unusual case of a double location of arteriosclerotic aneurysms of the ulnar artery and anterior tibial artery]

Multiple peripheral arteriosclerotic aneurysms are relatively rare. This is a report of a case of two arteriosclerotic aneurysms in unusual sites: ulnar artery and anterior tibial artery. Surgical treatment was: simple resection for the ulnar aneurysm; resection with restoration of arterial continuity for the tibial aneurysm.

A multicentre study on LMW-heparin effectiveness in preventing postsurgical thrombosis

A multicentric study was carried out involving six italian departments of general surgery to assess the efficacy of a low molecular weight (LMW) heparin called Fluxum compared to standard calcium heparin in low doses for prevention of postoperative thromboembolic complications (deep vein thrombosis and pulmonary embolism). 610 patients were treated; 308 (50.5%) of whom were treated with Fluxum at doses of 4,000 or 8,000 I.U. Axa once a day by subcutaneous injection and 302 (49.5%) with heparin calcium at doses of 5,000 I.U. two or three times a day by subcutaneous injection. We observed a total of 29 deep vein thrombosis (4.7%); 10 (3.2%) from the group treated with LMW heparin and 19 (6.3%) from the comparative group. During the study 4 (0.65%) pulmonary embolism were found, 1 (0.32%) in the group treated with LMW heparin and 3 (1%) in the group treated with calcium heparin. None serious hemorrhagic accident was reported during the study. The antithrombotic prophy laxis carried out with Fluxum was on the whole better tolerated than the treatment of the other group, registering a lower frequency of hematomas at the injection and surgical wound sites.