Unusual magnetic resonance imaging findings of cystic bone lesions in congenital generalized lipodystrophy.

Cystic bone lesions are the hallmark of skeletal abnormalities in patients with congenital generalized lipodystrophy (CGL). However, their pathophysiology is still unclear and theories about their origin remain largely speculative. This article reports on a patient with CGL and cystic bone lesions, some of them with unusual magnetic resonance imaging (MRI) findings that include elevated signal intensity on T1-weighted images and fluid-fluid levels, the latter evolving to a more "classic" cystic appearance on follow-up. Even though similar findings were first described almost 30 years ago, little attention was given to them back then; furthermore, other than the present report, no other study has performed sequential exams to follow their evolution in serial MRI. The authors conduct a review of the literature, hypothesizing that these remarkable findings may reflect an intermediate stage in the process of cystification of the abnormal bone marrow, incapable to perform adipose conversion, lending factual support to the modern theories about this issue.

Reproductive compensation in female Palaemonetes argentinus (Decapoda: Natantia) due to Microphallus szidati (Trematoda) infection.

Parasites may affect host demographic characteristics because they can directly or indirectly cause the death of their hosts and/or influence their reproduction. Parasitism is therefore recognized as a factor that influences the composition and structure of populations and communities. One of these behaviours is the compensatory response: the host can compensate for the parasite losses effect, modifying the reproductive effort to enhance fitness. Ovigerus female Palaemonetes argentinus was collected and sorted into two groups according to the degree of development of their embryos: newly spawned embryos and embryos ready to hatch. The number of embryos and their dry weight for each female were determined. All parts of the female body were checked for parasites. The females of P. argentinus were parasitized by Microphalus szidati. We found that parasitized females produce more embryos but had more egg loss during development and the percentage of embryonic loss was higher in the parasitized females than in non-parasitized. Parasitized females produced lighter eggs than those from uninfected females. This supports the compensatory reproduction hypothesis suggested for this species. Parasitism can change life history traits in a way that fecundity can be compensated; this co-evolution between host and parasites will be population or context dependent. Parasites are a functional part of any ecosystem and as our results show, deleting parasites in life history traits and reproduction studies in free living organisms could lead to an incomplete picture of the true processes that happen in nature.

First report of bacteremia by Janibacter terrae in humans.

The genus Janibacter comprises nine different species mainly found in the environment. Only two human infections by these microorganisms have been previously reported, one by J. melonis and another one by an undescribed Janibacter sp. Herewith we report the first human cases of infection by J. terrae in four bacteremic patients. The microorganisms were isolated from two consecutive blood cultures taken from four febrile patients with several underlying conditions. All patients were treated with antibiotics, two of them with favorable outcome. Two severely immunocompromised patients died, and one was treated with an antibiotic in vitro active against the isolate. Janibacter terrae was identified by phenotypic and 16S rDNA amplification methods. This report includes also the first data on antimicrobial susceptibility of this opportunistic pathogen. Clinical microbiologists should be aware of this microorganism which can be identified by phenotypic and molecular methods.

Segmentation of female pelvic cavity in axial T2-weighted MR images towards the 3D reconstruction.

The anatomies of pelvic structures are critical for the diagnosis of pelvic floor dysfunctions. However, because of the complex background, the imaging appearances of pelvic organs and muscles are frequently distorted by noise and partial volume effect. Magnetic resonance imaging with its clear imaging quality of the female pelvic cavity is preferred for many studies. As such, correct segmentations of the pelvic structures on MR images are required for accurate diagnoses. Effective algorithms for axial T2-weighted MR images have been proposed, which are based on the imaging features of different structures and various image clues. In this paper, we review these algorithms and evaluate their performance, and discuss implementation issues and aspects towards constructing the three-dimensional models.

A shape guided C-V model to segment the levator ani muscle in axial magnetic resonance images.

This paper proposes a modified Chan-Vese model to segment levator ani muscles from axial magnetic resonance (MR) images. Intensity variances of the foreground and the background are used as the main segmentation clues. As in most cases the boundary of the rectum can be successfully segmented in axial MR images, it is assumed as a priori and is used to define the region of interest and the initial contour. In order to handle the complex influences of the connective tissues, a shape influence field is formed based on the shape information of the rectum and is integrated into the Chan-Vese model. Several segmentation examples are presented to show the effectiveness of the proposed method and the necessity of adding the shape influences.

Isolation of Corynebacterium ureicelerivorans from normally sterile sites in humans.

Fifteen Corynebacterium ureicelerivorans isolates were recovered in pure culture from six patients during a five-year period. Five patients had bacteremia and the other was an infection of ascitic fluid. The API Coryne numerical profile obtained corresponds to the profile for C. bovis, while Biolog GP2 identified four out of the six isolates as C. jeikeium. The organisms were molecular identified by 16S rDNA and rpoB. The present report also includes information on new phenotypic tests and, for the first time, antimicrobial susceptibility data of C. ureicelerivorans and their rpoB sequences. All macrolide-resistant isolates presented a constitutive MLS phenotype. This organism must be differentiated from other slow-growing, lipophilic, and urea-splitting corynebacteria.

The isolation of Corynebacterium coyleae from clinical samples: clinical and microbiological data.

Fourteen Corynebacterium coyleae isolates were recovered from 12 in-patients during a 5-years period. In six patients, the isolates were considered as clinically significant, three definite (sepsis), two probable (sepsis and soft tissue infection), and one possible (post-transfusional bacteremia). In the remaining 6 patients (all neonatal bacteremias), there was not enough data for considering the isolates as clinical significant. API Coryne identified all isolates as C. jeikeium, while Biolog GP2 correctly identified 7 out of the 14 isolates. Definitive identification was achieved in all isolates by the sequencing of a fragment of 724 to 1423 pb of 16S rDNA. Successive isolations from two patients presented identical random amplified polymorphic DNA (RAPD) profiles. All of the isolates were in-vitro-sensitive to beta-lactams, gentamicin, rifampin, tetracycline, vancomycin, linezolid, and resistant to clindamycin. Resistance to erythromycin occurred in 83.3% of isolates, all of them presenting phenotype cMLS and harboring the gene ermX.

Rhombencephalosynapsis: CT and MRI findings.

An unusual disorder of cerebellar development, rhombencephalosynapsis is a unique entity which presents with cerebellar fusion and absence of cerebellar vermis on imaging studies, often associated with supratentorial findings. No specific clinical syndrome has been described in these patients so far, and most cases are found in infancy and childhood. MRI and its multiplanar capabilities and high spatial and contrast resolution increased its recognition. Two cases are reported, with emphasis on imaging findings.

[Incrusted cystitis with isolation of Corynebacterium group D2]. / Cistitis incrustante con aislamiento de Corynebacterium grupo D2.

Three cases of encrusted cystitis caused by Corynebacterium group D2 are described. The vesical damage previous to the establishment of this bacteria is noteworthy and the very rapid increase in urease activity explains the pathogenesis of the situation. Thus allowing for its identification and is relevant to treatment. Cloudy urine with a strong smell of ammonium, alkaline pH and crystals of ammonium magnesium phosphate in the sediment will bring this microorganism and its characteristic growth pattern to mind thus avoiding a falsely negative report. Treatment combining an antimicrobial agent and cystoscopic resection of the encrusted stones, where Corynebacterium group D2 has lodged, has proved efficacious. Vancomycin and teicoplanin have always been active and are eliminated through the kidneys.