Anatomic Variations of Intrahepatic Bile Ducts in a European Series and Meta-analysis of the Literature

Background  

Accurate knowledge of biliary anatomy and its variants is essential to ensure successful hepatic surgery; however, data from European countries are lacking.     

Molecular mechanisms associated with leukemic transformation of MPL-mutant myeloproliferative neoplasms

Somatic activating mutations in MPL, the thrombopoietin receptor, occur in the myeloproliferative neoplasms, although virtually nothing is known about their role in evolution to acute myeloid leukemia. In this study, the MPL T487A mutation, identified in de novo acute myeloid leukemia, was not detected in 172 patients with a myeloproliferative neoplasm. In patients with a prior MPL W515L-mutant myeloproliferative neoplasm, leukemic transformation was accompanied by MPL-mutant leukemic blasts, was seen in the absence of prior cytoreductive therapy and often involved loss of wild-type MPL by mitotic recombination. Moreover, clonal analysis of progenitor colonies at the time of leukemic transformation revealed the presence of multiple genetically distinct but phylogenetically-related clones bearing different TP53 mutations, implying a mutator-phenotype and indicating that leukemic transformation may be preceded by the parallel expansion of diverse hematopoietic clones.     

MYH9 related disease: four novel mutations of the tail domain of myosin‐9 correlating with a mild clinical phenotype

MYH9‐related disease (MYH9‐RD) is a rare autosomal dominant disorder caused by mutations in MYH9, the gene encoding the heavy chain of non‐muscle myosin IIA. All patients present congenital macrothrombocytopenia and inclusion bodies in neutrophils. Some of them can also develop sensorineural deafness, presenile cataract, and/or progressive nephropathy leading to end‐stage renal failure. We report four families, each with a novel mutation: two missense mutations, in exons 31 and 32, and two out of frame deletions in exon 40. They were associated with no bleeding diathesis, normal, or only slightly reduced platelet count and no extra‐hematological manifestations, confirming that alterations of the tail domain cause a mild form of MYH9‐RD with no clinically relevant defects.     

A New Generation of X-ray Baggage Scanners Based on a Different Physical Principle

X-ray baggage scanners play a basic role in the protection of airports, customs, and other strategically important buildings and infrastructures. The current technology of baggage scanners is based on x-ray attenuation, meaning that the detection of threat objects relies on how various objects differently attenuate the x-ray beams going through them. This capability is enhanced by the use of dual-energy x-ray scanners, which make the determination of the x-ray attenuation characteristics of a material more precise by taking images with different x-ray spectra, and combining the information appropriately. However, this still has limitations whenever objects with similar attenuation characteristics have to be distinguished. We describe an alternative approach based on a different x-ray interaction phenomenon, x-ray refraction. Refraction is a familiar phenomenon in visible light (e.g., what makes a straw half immersed in a glass of water appear bent), which also takes place in the x-ray regime, only causing deviations at much smaller angles. Typically, these deviations occur at the boundaries of all objects. We have developed a system that, like other “phase contrast” based instruments, is capable of detecting such deviations, and therefore of creating precise images of the contours of all objects. This complements the material-related information provided by x-ray attenuation, and helps contextualizing the nature of the individual objects, therefore resulting in an increase of both sensitivity (increased detection rate) and specificity (reduced rate of false positives) of baggage scanners.     

Distribution of filamentous fungi causing invasive fungal disease at the Haematological Unit,Hospital de Clínicas de Porto Alegre,Brazil

Very limited data are available in the literature to elucidate the aetiology of invasive mould infections in Latin America. Here we report that Aspergillus species caused only half of such cases in a cohort study conducted over 21 months in a university hospital in Porto Alegre, Southern Brazil. Fusarium spp. were the second most prevalent moulds (20.7%), followed by Zygomycetes (13.8%). The importance of obtaining local epidemiological data for adequately guiding empirical antifungal therapy is reinforced.     

Insights into the pathogenesis and management of thrombosis in polycythemia vera and essential thrombocythemia

The classic myeloproliferative neoplasms (MPNs) include polycythemia vera and essential thrombocythemia; their molecular basis has been described only recently with the demonstration of recurrent mutations in JAK2 or MPL. While life expectancy may not be significantly shortened, arterial and venous thrombosis constitute the major causes of morbidity and mortality, together with disease evolution to myelofibrosis or transformation to acute leukemia. Therapy is currently aimed at reducing the rate of thrombosis without increasing the risk of hematologic transformation by inappropriate exposure to cytotoxic drugs. Nevertheless, the mechanism(s) finally responsible for the increased thrombotic tendency have not been clearly elucidated, although risk factors for thrombosis have been identified, and are currently employed for stratifying patients to the most appropriate therapeutic options. Abnormalities of blood cells, activation of neutrophils and platelets, and a hypercoagulability state, can all act in conjunction to lead to thrombosis. Intriguing data also point to the JAK2V617F mutation as both a marker and a mechanism for thrombosis. Better knowledge in the pathophysiology of these disorders, and the introduction of molecularly targeted drugs in clinical trials, anticipate the possibility of more specific and efficacious treatment of classic MPN, particularly as concerns the reduction of risk associated with vascular events.     

High-Intensity Focused Ultrasound (HIFU)-Assisted Hepatic Resection in an Animal Model

Background

Bleeding is the main cause of postoperative complications of hepatic surgery. To minimize intraoperative bleeding during hepatectomy, resections are generally carried out under hepatic vascular control despite the risk of liver dysfunction in patients with chronic liver disease. This study evaluates the feasibility and safety of high-intensity focused ultrasound (HIFU)-assisted hepatic resection during an open procedure in an animal model.

Methods

Three groups of 12–14-week-old Landrace pigs (n = 7/group) were used to evaluate HIFU-assisted liver resection (group A) vs liver resection with or without portal triad clamping (groups B and C). In each pig, liver resection was performed on the right and left paramedian lobes. The following were evaluated and compared in the 3 groups: total blood loss, blood loss/cm² of resection area, clip density, procedure duration, morbidity, and mortality.

Results

Median blood loss was significantly lower in group A than in group B (P = .02), and group C (P = .007). Median blood loss/cm² of resection area was 4.77 mL/cm² in group A, 11.35 mL/cm² in group B, 12.22 mL/cm² in Group C. Precoagulation resulted in sealing blood vessels <5 mm; therefore, median clip density during liver transection was 0.78 clip/cm² in group A, 1.61 clip/cm² in group B, and 1.57 clip/cm² in group C. Median duration of the surgical procedure was 12 min in group A, 21 min in group B, and 19 min in group C.

Conclusions

HIFU-assisted hepatic resection during an open procedure in an animal model is safe, reduces bleeding, and allows real-time ultrasound guidance.