LOWER PLIOCENE BARNACLE FACIES OF WESTERN LIGURIA (NW ITALY): A PEEK INTO A WARM PAST AND A GLIMPSE OF OUR INCOMING FUTURE

The lower Pliocene deposits of Pairola (Liguria, Italy) display the otherwise rare occurrence of rock-forming amounts of barnacles (mostly belonging to the extinct Euromediterranean species Concavus concavus). Three main facies are recognised in the investigated succession: a barnacle-dominated facies, which formed along a shallow (<15 m deep) nearshore environment, a foraminifera-dominated facies from relatively deeper waters (40-100 m), and an intermediate facies forming at the boundary of the other two. These facies and their relationships suggest deposition in a flooded valley – a kind of setting that was common in the Mediterranean after the Messinian Salinity Crisis. Differing from other rias, the Pairola basin was exposed to strong waves, resulting in conditions favourable to barnacles. Sedimentological and stratigraphic observations indicate that the Pairola succession formed within a timespan covering both cold and warm phases. This is relevant because the sub-tropical foraminifer Amphistegina is ubiquitous throughout the succession. Amphistegina occurs in the Pliocene and lower Pleistocene (Gelasian) of Northern Italy, but not in the remainder of the Pleistocene, not even its warm portions. This genus is currently recolonizing the Mediterranean and is projected to reach the northern coast of the basin soon, foretelling that Anthropocene temperatures are going to overcome those of the late Pleistocene warm periods and reach those of the Pliocene

18F-FDG PET/CT demonstrated renal and hepatic cyst infection in a patient with autosomal dominant polycystic kidney disease

Infection of renal or hepatic cyst is a serious complication of autosomal dominant polycystic kidney disease (ADPKD) and early diagnosis is crucial for the correct management. We report a case of 64-year-old male with ADPKD, who required renal transplantation some years before, with recent recurrent episodes of fever and abdominal pain, who underwent 18F-FDG PET/CT twice at 18 months intervals, after not conclusive conventional imaging studies (CT, ultrasonography). 18F-FDG PET/CT has proven to be a useful method for the diagnosis of renal and hepatic cyst infection in a patient with ADPKD and for the subse­quent management

Incidental thyroid Tc-99m methylene diphosphonate (MDP) uptake in a patient affected by polynodular goiter at bone scintigraphy

Incidental extraosseous uptake seen on Tc-99m methylene diphosphonate (MDP) bone scan is not unusual. We discuss here an incidental thyroid uptake in a 55-year-old female patient affected by breast cancer treated by total mastectomy, who underwent total body bone scintigraphy as a staging study. In the positron emission tomography era, traditional nuclear medicine imaging still has an important role in the diagnostic field, and incidental findings may be very useful in patient management, revealing unknown diseases and allowing correct therapeutic decisions

Role of F-18-FDG-PET/CT in restaging of patients affected by gastrointestinal stromal tumours (GIST)

BACKGROUND: Gastrointestinal stromal tumours (GISTs) are a subset of mesenchymal tumours that represent the most common mesenchymal neoplasms of the gastrointestinal (GI) tract and account for less than 1% of all gastrointestinal tumours. MATERIAL AND METHODS: We retrospectively evaluated 19 patients (6 females and 13 males; median age: 61 years ± 15 standard deviation) affected by GIST histologically documented after surgical intervention or biopsy. RESULTS: F18-FDG-PET/CT had identified pathologic uptakes and was considered positive for neoplastic tissue in 10 patients (53%) and negative in 9 (47%), in concordance with radiological findings. CONCLUSIONS: F18-FDG-PET/CT is a feasible, reliable, and accurate method to restage patients affected by previously histologically confirmed GIST, also in the absence of a staging study. Nuclear Med Rev 2010; 13, 2: 76–8

Primary breast non-Hodgkin lymphoma. A report of an unusual case

Although lymphomas are generally considered as tumors oflymph nodes about 25-40% arise at extranodal sites. We reporta case of a 60 years old female who developed a right breastB-diffuse large cell non-Hodgkin lymphoma in 2005 treated bychemo/radio-therapy which relapsed at the same breast in 2007and at the other breast in 2010. The patient underwent bothradiologic and nuclear medicine studies.Although lymphomas are generally considered as tumors oflymph nodes about 25-40% arise at extranodal sites. We reporta case of a 60 years old female who developed a right breastB-diffuse large cell non-Hodgkin lymphoma in 2005 treated bychemo/radio-therapy which relapsed at the same breast in 2007and at the other breast in 2010. The patient underwent bothradiologic and nuclear medicine studies

Incidental 18F-FDG PET/CT bilateral breast uptake due to carcinoma

We report a case of 71-year-old female patient, previously treated with chemotherapy and surgical resection of sigmoid tract of the large bowel for adenocarcinoma (pT3N1M0), who underwent a 18F-FDG PET/CT for a suspicious hepatic lesion detected at CT scan during follow-up. 18F-FDG PET/CT showed no abnormal uptake in the liver both at 60 minutes and 120 minutes after injection but revealed a pathological uptake in two breast nodules, (one localized in upper-internal-quadrant of the right breast and the other in the upper-external-quadrant of the left breast). The patient underwent breast MRI, which confirmed the suspicious nature of both lesions; subsequently she underwent a trucut biopsy of both lesions witch demonstrated a bilateral localization of papillary carcinoma (both lesion were classified as pT1c). The patient underwent bilateral mastectomy and the final biopsy confirmed the presence of breast cancer, while bilateral sentinel nodes biopsy showed no lymph-nodes metastases

F18-FDG-PET/CT in a patient affected by Lynch syndrome

Lynch syndrome (LS) is the most common hereditary syndrome that predisposes patients to colorectal cancer, and it accounts for 2–5% of the total burden of colorectal cancer. We report a case of a 61-year-old female affected by Lynch syndrome who underwent multiple adenocarcinoma resections, studied by F18-FDG-PET/CT for 5 years. This case report suggests a potential role of F18-FDG-PET/CT in the evaluation of patients affected by Lynch syndrome. Nuclear Med Rev 2010; 13, 2: 87–8

A new large squalodelphinid (Cetacea, Odontoceti) from Peru sheds light on the early miocene platanistoid disparity and ecology

The South Asian river dolphin (Platanista gangetica) is the only extant survivor of the large clade Platanistoidea, having a well-diversified fossil record from the Late Oligocene to the Middle Miocene. Based on a partial skeleton collected from the Chilcatay Formation (Chilcatay Fm; southern coast of Peru), we report here a new squalodelphinid genus and species, Macrosqualodelphis ukupachai. A volcanic ash layer, sampled near the fossil, yielded the 40Ar/39Ar age of 18.78±0.08Ma (Burdigalian, EarlyMiocene). The phylogenetic analysis places Macrosqualodelphis as the earliest branching squalodelphinid. Combined with several cranial and dental features, the large body size (estimated body length of 3.5 m) of this odontocete suggests that it consumed larger prey than the other members of its family. Together with Huaridelphis raimondii and Notocetus vanbenedeni, both also found in the Chilcatay Fm, this new squalodelphinid further demonstrates the peculiar local diversity of the family along the southeastern Pacific coast, possibly related to their partition into different dietary niches. At a wider geographical scale, the morphological and ecological diversity of squalodelphinids confirms the major role played by platanistoids during the EarlyMiocene radiation of crown odontocetes

Looking for the key to preservation of fossil marine vertebrates in the Pisco Formation of Peru: new insights from a small dolphin skeleton

The upper Neogene Pisco Formation of Peru is known worldwide as one of the most significant Cenozoic marine vertebrate Konservatt-Lagerstätten, even featuring cetacean specimens that retain remains of soft tissues or stomach contents. Previous works showed that biomediated precipitation of dolomite concretions around large-sized decaying carcasses was one of the most relevant processes responsible for exceptional fossil preservation. In turn, little is known about the modes of fossilization of well-preserved small-sized vertebrates, which are rather common in the Pisco Formation, but mostly do not exhibit dolomite concretions. We report on a cetacean specimen, identified as belonging to the extinct short-snouted, small dolphin species Brachydelphis mazeasi (Pontoporiidae), preserved within a late Miocene sandy deposit at the site of Pampa Corre Viento. This specimen consists of a moderately disarticulated partial skeleton exhibiting well-mineralized bones; it is not enclosed within a dolomite concretion, being however delimited by an evident dark boundary in the host sediment. Scanning electron microscopy and microanalytical investigations identify Mn-oxides and apatite as early diagenetic minerals around the skeleton. We argue that a rapid burial of the specimen was pivotal for the preservation of the bones, and allowed the early establishment of anoxic processes for degradation of organic matter. Coupled with availability of P in porewater, the reducing conditions and the lowered pH allowed precipitation of Ca-phosphate while increasing Mn solubility close to the pontoporiid carcass. Mn-oxides precipitated at the redox boundary, the latter defining the outer edge of the volume of sediment affected by altered chemical conditions due to the decaying processes. The permeability of the sediment and the small size of the carcass were possible factors unfavorable to extensive sulfate reduction, thus preventing the formation of a dolomite concretion and allowing bone phosphatization. This record emphasizes the role of conditions favorable to bone mineralization in absence of an isolating carbonate concretion, in cases of high quality preservation of small-sized vertebrates observed in the Pisco Formation. The observation of patterns in the distribution of diagenetic minerals in the sediment enclosing vertebrate remains without, or with limited carbonate concretions provides insights into early taphonomic processes