Autochthonous Hookworm-Related Cutaneous Larva Migrans Disease in Northeastern Italy: A Case Report.

Here we report the case of a 42-yr-old patient who presented himself to us with a serpiginous erythematous lesion from the wrist of the right forearm up the arm to the right shoulder A similar lesion of a smaller size was also present in the left forearm. On the basis of clinical manifestations and progression of the lesion, combined with previous treatments and different diagnostic investigations, hookworm-related cutaneous larva migrans (HrCLM) disease was hypothesized. Albendazole was employed as treatment and the resolution of the symptoms confirmed the diagnosis. The relevance of the reported case relies on 3 main aspects: the acquisition of the disease in Italy, the initial treatment with topical corticosteroids that sped up the progression of the cutaneous trail, and the uncommon location of the lesions. Furthermore, the anamnestic data and the laboratory/clinical investigations strongly suggested an occupational exposure to the etiological agent. As illustrated here, HrCLM might represent a challenge for Western physicians in terms of diagnosis, treatment, and ways of acquisition. Describing the clinical presentation and the treatment of cases of cutaneous larva migrans might contribute to early and correct diagnosis, to an increase of our knowledge on this disease, and to an update on its epidemiology.

Molecular epidemiology of Enterococcus faecium isolates from an Italian hospital.

BACKGROUND: Outbreaks of vancomycin-resistant Enterococcus faecium (VRE) strains is an emerging problem worldwide. Even if still relatively uncommon in European hospitals, infections caused by VRE have also been increasing recently in this continent. METHODS: In this study, we characterized 50 consecutive VRE and 23 vancomycin-sensitive E. faecium (VSE) isolates collected in an Italian hospital. The presence of the esp gene and that of genes encoding resistance to glycopeptides was investigated by polymerase chain reaction (PCR). All of the isolates were typed by multi-locus sequence typing (MLST), and a selection of them also by pulsed-field gel electrophoresis (PFGE). RESULTS: We found that all of the VRE and 18 (78%) of the VSE strains belonged to the single clonal complex-17 (CC17). The most represented sequence type (ST) was ST78 (34% of the isolates). When further analyzed by PFGE, ST78 isolates were subdivided into five pulsotypes, four of them closely related. The strong association between the esp gene and CC17 was confirmed. Interestingly, such an association was higher among vancomycin-resistant isolates. Most of the esp-positive isolates (34/46, 74%) encoded Esp4, a rare variant of this protein characterized by the absence of A repeats. CONCLUSIONS: Our findings underscore the role of the CC17 lineage in the nosocomial spread of VRE and VSE, and its rapid local evolution, underscoring the need for programs designed to provide early detection in order to prevent its spreading among the nosocomial population.

[Dientamoeba fragilis: is it really fragile? Approach to specimen handling and rapid microscopic diagnosis]. / Dientamoeba fragilis: è realmente fragile? Approccio al trattamento del campione e diagnosi rapida al microscopio.

Dientamoeba fragilis is a pathogenic protozoan parasite with a world-wide distribution. Interestingly, a resistant cyst stage has not been demonstrated and it is still an unsolved problem how this parasite can survive successfully outside the human host. D. fragilis was found in 2% of approximately 2500 individuals unselected who submitted stools for parasitological examination during 2001 in Padua (Italy). The goal of this study was to detect the protozoan stages and the duration of persistence of this protozoa in faeces stored in different environmental conditions. The trophozoites of D. fragilis were detected up to 60 days after the collection of the faeces stored at 4 degrees C and Giemsa stained. The laboratory detection rate of the organism is greatly enhanced by use of preservative to fix stool specimens immediately after passage. Alternatively, a microscopic observation of the collected stool has to be performed immediately after passage followed by examination of permanently-stained smears. Demonstration of the charateristic "golf-club" and "acanthopodia-like" structures in unstained fixed faecal material by direct microscopy (400x) are suitable for a rapid identification of D. fragilis.

Developmental morphology of vascular and lymphatic capillaries in the working myocardium and Purkinje bundle of the sheep septomarginal band.

The normal development of vascular and lymphatic capillaries in the right ventricular septomarginal band of the sheep heart was studied in 9 fetuses aged 60-143 days (term = 147 days), 14 lambs aged 1 day to 16 weeks, and 3 adults. Tissue was fixed by perfusion and examined with light and transmission electron microscopy. The septomarginal band is composed of working myocardium and a well-defined peripheral bundle of Purkinje cells. Vascular capillaries of the working myocardium were closely apposed to myocardial cells. By contrast, vascular capillaries of the Purkinje bundle were situated within the connective tissue sheath and septa, at variable distances from the Purkinje cells. After birth, the capillaries of the Purkinje bundle were also found in grooves and tunnels within the Purkinje strands. The ultrastructure of fetal vascular capillaries associated with myocardial and Purkinje cells was initially similar, and characterized by an abundance of synthetic organelles in endothelial cells and pericytes. However, after 115 days in utero, capillary endothelium with diaphragmed fenestrae, 40-60 nm in width, were observed within the Purkinje bundle. The fenestrae attained an average frequency of 1 per 11 capillary cross sections just before term, and this was maintained in lambs and adults. The ultrastructure of lymphatic capillaries, which were not observed in the septomarginal band until just before term, changed little during development.

Differentiation and innervation of the atrioventricular bundle and ventricular Purkinje system in sheep heart.

The development of the atrioventricular bundle (AVB) and ventricular Purkinje system and their innervation have been studied in fetal sheep from 27 to 140 days gestation (term is 147 days). The AVB initially consisted of a primordium, which lacked innervation and was composed of small, relatively undifferentiated myocytes. Differentiation of Purkinje-like cells within the AVB began near its distal end and extended towards the atrioventricular node (AVN). Differentiation of the ventricular Purkinje system extended distally from the region of bifurcation of the AVB from cells that were indistinguishable from the working myocardium and continuous with the AVB primordium. Differentiation of Purkinje-like AVB cells was complete by 46 days gestation but Purkinje fibres were still differentiating within the ventricular wall at 60 days gestation. The main morphological changes included a large increase in cell size and organization into strands, development of characteristic glycogen-filled regions containing many intermediate filaments and early development of myofibrillar M lines compared to the working myocardium. The differentiation of AVB cells and the ventricular Purkinje system preceded their innervation. The AVB became innervated earlier than ventricular Purkinje fibres, intimate contacts between proximal AVB cells and nerve axons being present at 60 days gestation. Nerve fibres were present in the septomarginal band at this time, however, en passant associations with ventricular Purkinje fibres were rarely observed until 140 days gestation and intimate contacts were not present at any stage. Although the AVB and ventricular Purkinje system of adult sheep are composed of morphologically similar cells, the present study demonstrates that they differ in origin and their mode of differentiation as well as timing and intimacy of innervation. Innervation is not part of the developmental mechanism leading to the differentiation of Purkinje fibres. No primordium of the ventricular Purkinje system could be identified, suggesting that the mechanism of differentiation of ventricular Purkinje fibres involves recruitment from early working myocardium.

Autoradiographic localization of beta-1 and beta-2 adrenoceptors in guinea pig atrium and regions of the conducting system.

[125I]Cyanopindolol binding to slide mounted guinea pig atrial sections was time-dependent (Ki = 2.4 X 10(8) M-1 min-1, K-1 = 1.2 X 10(-3) min-1) saturable (24-32 pM) and stereoselective with respect to the isomers of propranolol. Competition binding curves with the beta-1 selective antagonist CGP 20712A and beta-2 selective antagonist ICI 118,551 revealed the presence of beta-1 and beta-2 adrenoceptors in the proportions of 85 to 15%. X-ray film exposed to sections of guinea pig heart incubated previously with [125I]cyanopindolol with or without ICI 118,551 (70 nM) or CGP 20712A (100 nM) or (-)-propranolol (1 microM) showed a high density and even distribution of beta-1 adrenoceptors and a lower density and even distribution of beta-2 adrenoceptors over the myocardium. Beta-2 adrenoceptors also were located in the epicardium, the adventitia of the pulmonary artery, aorta, superior and inferior vena cava and the endothelium of the superior and inferior vena cava. Development of nuclear emulsion-coated coverslips confirmed these observations and, in addition, localized beta-2 adrenoceptors to nerve tissue and the aortic valve. In the papillary muscle and surrounding Purkinje cells there was a high density and even distribution of beta-1 and a much lower density of beta-2 adrenoceptors. The atrioventricular node, atrioventricular bundle and ventricular Purkinje system also contained both beta-1 and beta-2 adrenoceptors and in comparison with the surrounding myocardium, these tissues had a slightly greater density of beta-2 adrenoceptors.

An improved perfusion technique for fixation of sheep myocardium.

Although sheep have been widely used as models in the study of cardiac physiology, corresponding morphologic and morphometric data are scanty. For meaningful correlation of morphometric data with physiological information, it is desirable that fixation of the heart occur under controlled conditions. This paper describes a technique for in situ, retrograde aortic perfusion fixation of sheep myocardium under conditions of controlled pressure and minimal wastage of fixative. This is achieved by the application of snares around the brachiocephalic trunk and aortic arch, which are tightened at the start of the perfusion. These isolate the ascending aorta and the coronary vasculature from the remainder of the circulation and allow fixation of the whole heart at a controlled pressure. The method produces good fixation and contrast for transmission electron microscopy and is applicable to late-gestation fetuses, lambs, and adult sheep.

Cardiac Purkinje cells in culture.

Purkinje cells from false tendons of young rabbits, pigs and fetal lambs were dispersed by the action of collagenase and elastase and grown in culture for up to 14 days. Immunofluorescent staining with fluorescein-labelled antibodies to cardiac myosin and tropomyosin demonstrated cross-banding and/or a diffuse positive stain in Purkinje cells between 3 and 7 days in culture. Electron microscopy of cultured Purkinje cells at 3 days and 7 days revealed some disorganization of the myofilament system, in particular loss of Z-band material, as well as many thickened Z-bands, 120 nm to 240 nm in width. Gap junctions remained but desmosomes and fasciae adherentes were fewer in number. Organelles such as ribosomes, glycogen and mitochondria did not alter. Some Purkinje cells were spontaneously contractile in culture for up to seven days. Dominguez and Fozzard [7] propose that buckling of the Purkinje fibre and the production of sarcolemmal folds on the cell surface affect conduction of electrical impulses. We suggest that Purkinje cell contraction may play a major part in producing these geometric changes affecting conduction.

The demonstration of close nerve-Purkinje fibre contacts in false tendons of sheep heart.

An observation of intimate nerve-Purkinje fibre associations in false tendons of sheep heart is reported. Nerve bundles were observed in deep clefts of Purkinje fibres, in channels running between coupled Purkinje cells and embedded within Purkinje cells, as well as in the outer connective tissue sheath. Most nerve terminals in these areas were filled with small clear vesicles and a few large dense-cored vesicles. Only a few axons with many small dense-cored vesicles were observed. Intimate associations (separation, 60 to 90 nm) between the Purkinje cell and nerve varicosity were observed in the deep clefts. Similar close appositions were also present where nerves were embedded in Purkinje cells. In these cases the Purkinje cell enclosing the nerve bundle formed intercellular junctions with its own sarcolemma. Elaborate sarcolemmal folds with multi-vesicular bodies were also frequently observed near nerve bundles and varicosities. The identity of the transmitter is unknown although the nerves forming intimate associations with Purkinje cells have a morphology typical of cholinergic nerves.

Sheep cardiac Purkinje fibers: configurational changes during the cardiac cycle.

Previous attempts to study the cytoarchitecture of cardiac Purkinje fibers with the scanning electron microscope (SEM) have been limited by the surrounding dense connective tissue. In this study the connective tissue was removed by treatment with 8N HCl, after adult sheep hearts were fixed in diastole or systole and tissue taken for SEM and transmission electron microscopy (TEM). In SEM, Purkinje fibers freely anastomosed in false tendons and formed a subendocardial plexus. In systole, medium and small-sized Purkinje fibers formed deep clefts not observed in diastole. The clefts are thought to be due to sarcolemmal folding and fiber buckling and may therefore affect conduction. The myofibrils beneath the laterally apposed sarcolemmas of adjacent Purkinje cells when fixed in systole were often observed as tightly curved arches in series. Similar configurations with expanded arches were observed in diastole. The formation of arches by myofibrils is unique to Purkinje fibers and is interpreted as the mechanism responsible for their compliance to stretch. The significance of contraction in producing the observed geometric changes in Purkinje fibers and the implications of their cytoarchitecture with respect to conduction are discussed.