Os parietale partitum: Exploring the prevalence of this trait in four contemporary populations.

Os parietale partitum is a variable segmentation of the parietal bone. This manifests as a parietal division in the anteroposterior or superoinferior planes that is separated by an unusual suture and can be complete or incomplete. The existence of parietal divisions was observed and documented more than 260 years ago. The main objectives of this paper are to record the incidence of this rare trait in four modern populations with no previous records of it and provide a review of the literature. Four contemporary skeletal collections from Crete (Greece), Limassol (Cyprus), Coimbra (Portugal) and Salvador (Brazil) were assessed by the authors of this paper for non-metric cranial traits. Out of 711 skulls, only three cases of parietal division were found and all three originated from the Cypriot collection. These three cases were anatomically analyzed, showing that all three cases were adult females and showed unilateral expression of the trait. Two skulls showed superoinferior division, and the third case showed anteroposterior division. Numerous other cranial non-metric traits were found in these three skulls. Based on the cemetery archives, there seems to be no genetic link between the individuals bearing this trait. Further genetic analysis is suggested in order to verify this conclusion.

Endocarditis caused by unusual Streptococcus species (Streptococcus pluranimalium).

BACKGROUND: Infective endocarditis in intravenous drug abusers is caused mainly by Staphylococcus species and usually affects the right heart valves. CASE DESCRIPTION: We report the case of a 37-years-old intravenous drug abuser, who was diagnosed with infective endocarditis of the mitral and aortic valve. An unusual Streptococcus species (Streptococcus pluranimalium) was isolated from surgical specimens (peripheral arterial emboli, valves' vegetations) which, according to the literature, is related to animals' diseases such as infective endocarditis in adult broiler parents, with no references existing regarding causing such disease in humans. This unusual coccus infection caused specific clinical features (sizable vegetation on mitral valve >2cm, smaller vegetations on aortic valve, systemic emboli), resistance to antimicrobial therapy, rapid progression of the disease (despite of medical therapy and surgical replacement of both valves), and finally the death of the patient two months after the initial presentation of infective endocarditis. CONCLUSION: Unusual cases of infective endocarditis in intravenous drug abusers are emerging and are characterized by changing microbiological profile and varying clinical characteristics. Clinical doctors must be aware of these cases, especially when their patients present an atypical clinical course, and reappraise their medical management. Hippokratia 2015; 19 (2):182-185.

The good student is more than a listener - The 12+1 roles of the medical student.

BACKGROUND: The process of medical education, particularly in the fast evolving new era of medical metaschools, is a broad and complex issue. Harden & Crosby claimed that a good teacher is more than a lecturer, and identified 12 roles that certify a good and capable teacher. However, this is only half the truth: the good student is more than a listener. Teaching-and-learning is not simply a one-way process, and, as medical students are not children, the relationship between teacher and students involves andragogy rather than pedagogy. We therefore propose the 12+1 roles of the student. SUMMARY OF WORK: The Harden & Crosby paper was distributed in a class of 90 third year Ioannina University medical students, who were asked to think about the student's roles. A small discussion group brainstormed ideas, which were then refined further by the authors. SUMMARY OF RESULTS: 12+1 roles of the good medical student were produced and grouped into six areas: information receiver, in lectures and clinical context; role model in learning, in class, with the added subarea of comparative choice of role models; teaching facilitator and teacher's mentor; teacher's assessor and curriculum evaluator; active participator and keeping-up with curriculum; resource consumer/co-creator and medical literature researcher. The ideal student should fulfil the majority if not all of these complementary roles. TAKE-HOME MESSAGE: These 12+1 student's roles are complementary to the 12 roles of the teacher and help reshaping our understanding of today's medical education process.

Muon spin relaxation studies of magnetic-field-induced effects in high-Tc superconductors.

Muon spin relaxation measurements in high transverse magnetic fields [FORMULA: SEE TEXT] revealed strong field-induced quasistatic magnetism in the underdoped and Eu-doped (La,Sr)2CuO4 and La1.875Ba0.125CuO4, existing well above Tc and TN. The susceptibility counterpart of Cu spin polarization, derived from the muon spin relaxation rate, exhibits a divergent behavior towards T approximately 25 K. No field-induced magnetism was detected in overdoped La1.81Sr0.19CuO4, optimally doped Bi2212, and Zn-doped YBa2Cu3O7.

Muon spin relaxation and susceptibility studies of the pure and diluted spin 1/2 kagomé-like lattice system (CuxZn(1-x))3V2O7(OH2) 2H2O.

Muon spin relaxation and magnetic susceptibility measurements have been performed on the pure and diluted spin 1/2 kagomé system (CuxZn(1-x))3V2O7(OH)2 2H2O. In the pure x=1 system we found a slowing down of Cu spin fluctuations with decreasing temperature towards T approximately 1 K, followed by slow and nearly temperature-independent spin fluctuations persisting down to T=50 mK, indicative of quantum fluctuations. No indication of static spin freezing was detected in either of the pure (x=1.0) or diluted samples. The observed magnitude of fluctuating fields indicates that the slow spin fluctuations represent an intrinsic property of kagomé network rather than impurity spins.

Superconductivity and field-induced magnetism in Pr2-xCexCuO4 single crystals.

We report muon-spin rotation and relaxation (muSR) measurements on single crystals of the electron-doped high-T(c) superconductor Pr2-xCexCuO4. In a zero external magnetic field, superconductivity is found to coexist with dilute Cu spins that are static on the muSR time scale. In an applied field, we observe a mu(+)-Knight shift that is primarily due to the magnetic moment induced on the Pr ions. Below the superconducting transition temperature T(c), an additional source of local magnetic field appears throughout the volume of the sample. This finding is shown to be consistent with field-induced antiferromagnetic ordering of the Cu spins. Measurements of the temperature dependence of the in-plane magnetic penetration depth lambda(ab) in the vortex state are also presented.

Plasma atrial natriuretic peptide in essential hypertension after treatment with terazocin.

The aim of this study was to evaluate the medium term effects of the selective alpha1-adrenenergic- blocker terazocin on atrial natriuretic peptide (ANP) levels in patients with moderate essential hypertension. The drug was given orally for 30 days. The daily dose was 1 mg for the first 7 days, 2 mg for the next 7 days and 5 mg for the remaining period of this clinical trial. At the end of this clinical trial, plasma ANP levels increased by 16.40% despite the drop in blood pressure while left atrial and ventricular diameters remained unchanged. These findings indicate that the increase of ANP plasma levels is not the result of a mechanical load on the left cardiac chambers but the result of a pharmacological action. These observations also indicate that terazocin exerts part of its antihypertensive action by increasing ANP plasma levels.

Field dependence of the muon spin relaxation rate in MnSi.

Muon spin rotation/relaxation measurements have been performed in the itinerant helical magnet MnSi at ambient pressure and at 8.3 kbar. We have found the following: (a) the spin-lattice relaxation rate 1/T(1) shows divergence as T1T proportional, variant (T-T(c))(beta) with the power beta larger than 1 near T(c); (b) 1/T(1) is strongly reduced in an applied external field B(L) and the divergent behavior near T(c) is completely suppressed at B(L)> or =4000 G. We discuss that (a) is consistent with the self-consistent renormalization theory and reflects a departure from "mean-field" behavior, while (b) indicates selective suppression of spin fluctuations of the q=0 component by B(L).

Interaction of CD46 with measles virus: accessory role of CD46 short consensus repeat IV.

To define further the accessory role(s) of the CD46 (membrane cofactor protein) short consensus repeat (SCR) III and IV domains in the interaction of CD46 with measles virus (MV), chimeric proteins were generated by substituting domains from the structurally related protein decay accelerating factor (DAF, CD55): x3DAF (exchange of CD46 SCR III) and x4DAF (exchange of SCR IV). Transfected CHO cell lines that stably expressed these chimeric proteins were compared for MV binding and infection. Compared with wild-type CD46 (I-II-III-IV), a significant decrease in MV binding was observed with x4DAF. Despite this limited binding, these cells were still capable of supporting virus entry. In a quantitative fusion assay, no significant differences in fusion were observed as a result of the exchange of either CD46 SCR III or IV. However, the down-regulation of cell surface CD46 typically observed following MV infection was abolished with x4DAF, as was the redistribution of CD46 on the cell surface. Thus, CD46 SCR IV appears to be required for optimal virus binding and receptor down-regulation, although importantly, in spite of these functional limitations, x4DAF can still be used for MV entry.

Chimeric CD46/DAF molecules reveal a cryptic functional role for SCR1 of DAF in regulating complement activation.

Chimeric proteins using membrane cofactor (CD46) and decay accelerating factor (DAF or CD55) were generated to further investigate the functional domains involved in the regulation of human serum complement. Following activation of the classical pathway, the isolated substitution of CD46 SCR III (x3DAF) exhibited a modest regulatory activity comparable to that of CD46. The isolated substitution of CD46 SCR IV (x4DAF), and the combined CD46 SCR III+IV substitutions (x3/4DAF) were essentially as efficient as DAF. No regulation of C3b deposition was observed with the combined CD46 SCR I+II substitutions (x1/2DAF). When tested after activation of the alternative pathway, both the x3DAF and x3/4DAF chimeras failed to regulate C3b deposition, while the x4DAF chimera still displayed some activity. In contrast to that observed following classical pathway activation, the x1/2DAF chimera exhibited a similar efficiency to wild type CD46 and DAF in controlling C3b deposition. Using SCR specific antibodies, the regulatory activity of the x1/2DAF chimera against the alternative pathway was mapped to the first three distal SCR (i.e. DAF 1, DAF 2 and CD46 III). These data demonstrate that several combinations of SCR domains from two related complement regulators can result in functional molecules, and reveal a novel and cryptic functional role for DAF SCR1.

The effect of D-penicillamine on metallothionein mRNA levels and copper distribution in mouse hepatocytes.

Penicillamine increases the levels of metallothionein (MT) mRNA in a time and concentration dependent manner without altering either the rate of copper uptake or the amount of copper within the cell. The effect is dependent on the presence of intracellular copper, however, since depletion of copper by chelators blocks the effect, and does not alter the ability of dexamethasone to stimulate mRNA production. Penicillamine did not alter the distribution of 64Cu in the hepatocytes, as measured by fast protein liquid chromatography (FPLC), although the pattern may be affected by the amount of MT present. The data indicates that penicillamine removes copper from some intermediary ligand, thereby making it available to induce metallothionein. It is possible that this is part of the therapeutic action of the chelator in the treatment of Wilson's disease.