Italian intersociety consensus statement on antithrombotic prophylaxis in hip and knee replacement and in femoral neck fracture surgery

Anticoagulant prophylaxis for preventing venous thrombembolism (VTE) is a worldwide established procedure in hip (HR) and knee replacement (KR) surgery, as well as in the treatment of femoral neck fractures (FNF). Different guidelines are available in the literature, with quite different recommendations. None of them is a multidisciplinary effort as the one presented. The Italian Society for Studies on Hemostasis and Thrombosis, the Italian Society of Orthopedics and Traumatology, the association of Orthopedic Traumatology of Italian Hospitals, together with the Italian Society of Anesthesia, Analgesia, Resuscitation, and Intensive Care have set down easy and quick suggestions for VTE prophylaxis in HR and KR surgery as well as in FNF treatment. This inter-society consensus statement aims at simplifying the grading system reported in the literature, and thus at improving its proper application. Special focus is given to fragile patients, those with high bleeding risk, and on those receiving chronic antiplatelet and vitamin K antagonists treatment. A special chapter is dedicated to regional anesthesia and VTE prophylaxis.     

Amphiregulin and epidermal hyperplasia: amphiregulin is required to maintain the psoriatic phenotype of human skin grafts on severe combined immunodeficient mice

Overexpression of amphiregulin has been shown to induce psoriasiform changes in the skin of transgenic mice shortly after birth. Therefore, amphiregulin has been suggested as a target for anti-psoriatic therapy. To test this theory, a humanized monoclonal antibody capable of neutralizing human amphiregulin was examined for anti-proliferative effects in the human skin-severe combined immunodeficient (SCID) mouse transplant model. The anti-amphiregulin antibody reduced epidermal thickness of transplanted psoriatic skin and also inhibited the hyperplastic response that developed in nonpsoriatic skin after transplantation. The same antibody also suppressed keratinocyte proliferation in monolayer culture in a dose-dependent manner. Under the same conditions in which keratinocyte proliferation was inhibited, the antibody had little effect on proliferation of human dermal fibroblasts and no effect on type I procollagen production by these cells. Taken together, these data indicate an important role for amphiregulin in psoriatic hyperplasia and suggest that inhibition of amphiregulin activity could be an efficacious therapeutic strategy for psoriasis. These data also suggest that the hyperplastic response occurring in nonpsoriatic human skin on transplantation to the SCID mouse is mediated, in large part, by amphiregulin.     

Haemoglobin levels in autoimmune haemolytic anaemias at diagnosis: relationship with immunoproteins on red blood cells

Previous investigations of the relationship between characteristics of immunoproteins on red blood cells (RBCs) and the occurrence of autoimmune haemolysis yielded divergent results. Here, we studied these characteristics in autoimmune haemolytic anaemias (AIHAs) to determine their relationship with the degree of anaemia at diagnosis. We studied at diagnosis 52 cases of warm AIHA with positive direct antiglobulin test. Immunohaematological testing and determination of immunoglobulin class, complement, and immunoglobulin G (IgG) were performed using gel technology (GCT). Median haemoglobin (Hb) levels significantly differed between cases with IgG1 only or negative for IgG subclasses (7.4 g/dl), those with IgG3 or IgG1 + IgG3 (6.5 g/dl), and those with multiple immunoglobulins (5 g/dl). Logistic regression indicated that IgG3 detection was the only variable significantly related to the occurrence of RBC transfusion in AIHA (odds ratio 4.05, 95 % CI 1.1–14.7). In our study, the type of immunoprotein(s) on the RBC surface was associated with different Hb levels at AIHA diagnosis. IgG3 and multiple immunoglobulins were associated with lower Hb levels; IgG3 was also associated with a higher percentage of patient transfusions in the first week after diagnosis. Thus, qualitative differences in these immunoproteins may lead to deeper and more prolonged anaemia levels, influencing the need for RBC transfusion.     

Platelet-Associated IgG in Acute and Chronic Hepatic Diseases

In order to investigate the role of an immune mechanism in the pathogenesis of thrombocytopenia in hepatic patients, we measured platelet associated IgG (PAIgG) in 84 patients with various hepatic diseases. Increased PAIgG levels were found in 84% of patients with chronic active hepatitis (mean 21.32 ± 8.45 fg/platelet) and in 75% of those with cirrhosis with hepatitis (mean 17.3 ± 11.2 fg/platelet). In these patients there was no significant correlation between PAIgG and platelet count. Increased PAIgG amounts were also observed in some patients with inactive cirrhosis (18%). Normal PAIgG values were found in all patients with acute viral hepatitis and chronic persistent hepatitis. An immunologic mechanism may play a role in the pathogenesis of thrombocytopenia in hepatic patients. Furthermore, measurement of PAIgG may have a great usefulness in the differential diagnosis of chronic hepatic diseases.     

Inhibition in vitro of platelet aggregation and arachidonic acid metabolism by flavone

The effects of flavone on platelet aggregation and arachidonic acid (AA) metabolism were tested in vitro. When incubated at a concentration of 50 μM, flavone completely suppressed platelet aggregation induced by 150 μM AA in thirty-six out of forty-three subjects tested. A lower concentration (10 μM) was effective in about 50% of the donors. Flavone also inhibited the second wave of aggregation induced by epinephrine and ADP. Platelet thromboxane formation, estimated both by radioimmuno-assay measurements and by studies of ¹⁴C-labeled AA metabolism, was depressed by flavone. Flavone-treated platelets preferentially utilized [¹⁴C]AA for the lipoxygenase pathway while cyclo-oxygenase activity was depressed. Adenosine 3':5'-cyclic monophosphate (cAMP) was measured in flavone-treated and control platelets. While their baseline levels were similar, flavone-treated platelets showed a lower stimulation of cAMP induced by prostacyclin (PGI₂) than did controls. Phosphodiesterase activity was not affected by flavone as judged from the decay rates of PGI₂-stimulated cAMP levels. From these findings we conclude that the antiaggregating activity of flavone is not a consequence of changes in platelet cAMP but is due to inhibition of cyclo-oxygenase.     

Platelet activation in patients with benign and malignant ovarian diseases

Plasma concentration of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) were measured by radioimmunoassay in 45 patients with benign and malignant ovarian diseases. All patients with ovarian carcinoma showed increased beta-TG and PF4 levels. Among benign ovarian diseases the patients with serous cystadenoma more frequently showed signs of platelet activation, whereas those with endometriotic cyst and mucinous cystadenoma generally had normal beta-TG and PF4 values. These results indicate that an increased platelet activation is consistently associated with malignant tumors of the ovary, whereas benign tumors show a different capacity to induce platelet activation.     

Modification of platelet function and arachidonic acid metabolism by bioflavonoids. Structure-activity relations

The mechanism of the antiaggregating activity of flavonoids was studied in vitro. The activity of fifteen different compounds was tested on platelet aggregation and arachidonic acid metabolism. The effect of flavonoids on platelet adenosine 3',5'-cyclic monophosphate (cyclic AMP) levels under basal conditions, as well as after stimulation by prostacyclin (PGI2), was also measured. The glycons of flavonoids in general and the flavanone derivatives that we tested did not affect platelet function. On the other hand, flavone, chrysin , apigenin and phloretin inhibited platelet aggregation by depressing the cyclooxygenase pathway. In addition, flavone, chrysin and apigenin reduced the platelet cyclic AMP response to PGI2. This effect was probably mediated by an inhibition of adenylate cyclase. Myricetin and quercetin, however, increased the PGI2-stimulated rise of platelet cyclic AMP. Both of these flavonoids inhibited primarily lipoxygenase activity. Modification of platelet cyclic AMP metabolism through inhibition of phosphodiesterase activity was found to be the probable mechanism of their antiaggregating effect.     

An easy, cost-effective and time-conserving method of studying the vascular anatomy of the base of the skull

In this work we present a simple, rapid, cost-effective and time-conserving method of studying the vascular anatomy of the base of the skull. This method is based on the injection of the arteries and veins with an appropriate coloring solution that possesses the property of rapid solidification. This technique of preparation of the coloring solution and the method of injection is described in detail. The advantages and disadvantages of this technique are also discussed.