Organ-sparing surgery of the bilateral testicular large cell calcifying sertoli cell tumor in patient with atypical Peutz–Jeghers syndrome

Large cell calcifying sertoli cell tumor (LCCSCT) is an exceptionally rare neoplasm originating from sperm cord cells. The tumors have relatively low malignant potential and unlikely proceed to metastasis formation. The lesions may occur in an isolated form or in ca. 40% of cases may be associated with genetic abnormalities, by and large Peutz-Jeghers syndrome and Carney complex. At presentation, 20% of LCCSCT cases are bilateral and/or multifocal. Owning to characteristic skin lesions and particular hyperechoic ultrasound image of the tumor, preliminary diagnosis of the syndromic LCCSCT is possible in the preoperative period. Consequently, testicle organ-sparing procedure can be attempted, which is especially justified in bilateral lesions. Here, we report a case of a bilateral LCCSCT in a 20-year-old man with atypical Peutz-Jeghers syndrome due to amplification of the exon 1 of STK11 gene who was successfully treated with bilateral testicle-sparing tumorectomies.     

Effect of implanted bisphosphonate-enriched cement on the trabecular microarchitecture of bone in a rat model using micro-computed tomography

Purpose

Bisphosphonates (BPs) are antiresorptive drugs typically used to inhibit bone resorption. The latest reports show that BPs play an important role in not only achieving better bone mineral density but also in improving bone microarchitecture. The mechanism of action of the BPs is complex and multifactorial. We tried to determine whether there are any changes in the microarchitectural bone structure during local use of BP (Pamifos 60). The aim of this study was to see if BP-enriched cement used in rat models had positive effects on bone formation.

Methods

Research was performed on 40 adult male Wistar rats that were divided into four groups: two control groups and two experimental groups. Rats in the experimental groups were implanted with BP-enriched cement into the bone, while the control group rats were implanted with clean bone cement (without BP). Micro-computed tomography was applied for the investigation of trabecular microarchitecture of the proximal physis of the tibial bone in all animals three and six weeks after surgery. In all microCT images variables such as bone volume density (BV/TV), trabecular thickness (TbTh), trabecular separation (TbSp) and trabecular number (TbN) were used to describe trabecular bone morphometry.

Results

The major finding of this study is that using BP-enriched cement results in distinct changes in bone microarchitecture. We showed that local use of pamidronate (Pamifos 60) in orthopaedic cement had a positive effect on bone formation. It significantly changed three variables. We noticed increasing bone volume fraction and trabecular thickness together with decreasing trabecular separation.

Conclusion

In this paper we demonstrate the efficacy of using BP-enriched cement in vitro in the tibiae of rats. Our most significant finding based on micro-CT picture analysis allows us to start further work on more suitable applications of BP-enriched cement in humans. We believe that future successful experiments will facilitate potential use of BP-enriched cement in clinical applications.     

Multimodal imaging of brain reorganization in hearing late learners of sign language

The neural plasticity underlying language learning is a process rather than a single event. However, the dynamics of training‐induced brain reorganization have rarely been examined, especially using a multimodal magnetic resonance imaging approach, which allows us to study the relationship between functional and structural changes. We focus on sign language acquisition in hearing adults who underwent an 8‐month long course and five neuroimaging sessions. We assessed what neural changes occurred as participants learned a new language in a different modality—as reflected by task‐based activity, connectivity changes, and co‐occurring structural alterations. Major changes in the activity pattern appeared after just 3 months of learning, as indicated by increases in activation within the modality‐independent perisylvian language network, together with increased activation in modality‐dependent parieto‐occipital, visuospatial and motion‐sensitive regions. Despite further learning, no alterations in activation were detected during the following months. However, enhanced coupling between left‐lateralized occipital and inferior frontal regions was observed as the proficiency increased. Furthermore, an increase in gray matter volume was detected in the left inferior frontal gyrus which peaked at the end of learning. Overall, these results showed complexity and temporal distinctiveness of various aspects of brain reorganization associated with learning of new language in different sensory modality.     

Determination of efavirenz,a selective non-nucleoside reverse transcriptase inhibitor,in human plasma using HPLC with post-column photochemical derivatization and fluorescence detection

Methods for the quantitative determination of efavirenz in human plasma and the qualitative assessment of the stereochemical integrity of efavirenz in post-dose human plasma samples are described. After the addition of an internal standard, plasma samples were extracted with hexane-methylene chloride (65/35, v/v%). The extracts were evaporated to dryness and reconstituted in mobile phase. Upon exposure to UV light, the analyte was found to form fluorescent products; the major fluorescent product was isolated and identified as a substituted quinoline. Thus, the plasma extracts were analyzed via HPLC with post-column photochemical derivatization and fluorescence detection. Reverse phase chromatography was used for the quantitative assay, whereas chromatography with a column containing a chiral stationary phase (dinitrobenzoyl leucine) was used for the stereochemical assessment. The quantitative assay has been validated in the concentration range of 50-1000 ng/ml using 0.5 ml samples. Analyte recovery was better than 89% at all points on the standard curve. Intra-day precision was better than 5% C.V., while accuracy was between 95 and 104% of nominal over the range of the assay. The selective detection method reduces the likelihood of interference by co-administered medications or endogenous species. The stereochemical configuration of efavirenz was confirmed to remain intact in post-dose human plasma samples. The quantitative method has been successfully utilized to support a study in which a possible drug interaction between co-administered HIV protease inhibitors and efavirenz was evaluated.     

MRI in patients with urethral stricture: a systematic review

Magnetic resonance imaging (MRI) is gaining acceptance as a diagnostic tool in urethral stricture disease. Numerous publications emphasize on the advantages of MRI including its ability to determine periurethral spongiofibrosis, thus overcoming the main limitation of retrograde urethrography (RUG). It is also becoming an alternative for sonourethrography (SUG), which is a highly subjective examination. Magnetic resonance urethrography (MRU) has become an increasingly appreciated tool for diagnosing patients with urethral stricture disease. Obtained data provides radiologists and urethral reconstructive surgeons with additional information regarding anatomical relationships and periurethral tissue details, facilitating further treatment planning. Considering the great prevalence of urethral stricture disease and necessity of using accurate, and acceptable diagnostic method, this review was designed to provide radiologists and clinicians with a systematic review of the literature on the use of MRI in the urethral stricture disease.

Urethral stricture is one of the common male urological disorders with an increasing incidence. Patients may be asymptomatic or present with decreased urine flow, increased pressure required for urinating, a feeling of incomplete urination, urinating in a drop by drop manner and urinary retention. Moreover, ejaculation disorders, often underestimated by physicians, may be encountered, significantly influencing patients’ quality of life (1).Stricture might be caused by inflammatory, traumatic, ischemic, congenital or iatrogenic factors resulting in formation of scar tissue along the tract and reducing the caliber of the urethra (2). Disease is associated with high recurrence rate. Mechanisms underlying traumatic strictures include straddle injury, pelvic fracture-related urethral injury and iatrogenic injury secondary to instrumentation also in reference to worldwide increase in endoscopical transurethral treatment methods in the last decades (3).Given that the number of patients suffering from urethral stricture disease is increasing, there is a need for improvement of diagnostic methods determining the choice of the optimal treatment method. Despite numerous surgical methods for treatment of this disease, it is still associated with high recurrence rates.Process of stricture formation is usually associated with scarring within corpus spongiosum and is known as spongiofibrosis. Histological and immunohistochemical studies showed significant changes within the structure of the strictured part of urethral wall in the microscopic images. In contrast to normal urethra wall, the epithelial layer at the site of a stricture is much thicker. Collagen and bundles of elastin are densely packed around the strictured urethra (4). Thus, the most effective method of treatment for patients with urethral stricture with extensive spongiofibrosis is excision of the whole stricture followed by an end-to-end anastomosis of the two healthy ends (5). Therefore, more and more radiologists and urologists require information on the presence of spongiofibrosis and periurethral pathologies for the correct choice of treatment method.     

Pigs vs people: the use of pigs as analogues for humans in forensic entomology and taphonomy research

International Journal of Legal Medicine - Most studies of decomposition in forensic entomology and taphonomy have used non-human cadavers. Following the recommendation of using domestic pig...     

Blowfly puparia in a hermetic container: survival under decreasing oxygen conditions

Despite widely accepted standards for sampling and preservation of insect evidence, unrepresentative samples or improperly preserved evidence are encountered frequently in forensic investigations. Here, we report the results of laboratory studies on the survival of Lucilia sericata and Calliphora vomitoria (Diptera: Calliphoridae) intra-puparial forms in hermetic containers, which were stimulated by a recent case. It is demonstrated that the survival of blowfly intra-puparial forms inside airtight containers is dependent on container volume, number of puparia inside, and their age. The survival in both species was found to increase with an increase in the volume of air per 1 mg of puparium per day of development in a hermetic container. Below 0.05 ml of air, no insect survived, and above 0.2 ml of air per 1 mg of puparium per day, survival reached its maximum. These results suggest that blowflies reveal a single, general pattern of survival under decreasing oxygen conditions and that this pattern is a product of number of developing insects, their age and the initial amount of available air. Implications for forensic entomology are discussed.     

Retrieval mechanisms for autobiographical memories: insights from the frontal variant of frontotemporal dementia

Very few studies have investigated autobiographical memory in the frontal variant of frontotemporal dementia (fv-FTD). The aim of this study was therefore to unravel the mechanisms of autobiographical memory disruption in general and in the anterograde and retrograde components of amnesia in particular, in patients suffering from fv-FTD. An autobiographical memory task assessing overall (AM) and strictly episodic memories (EM) from five lifetime periods covering the entire lifespan revealed the absence of a temporal gradient for both scores, suggesting the existence of a retrieval deficit. An analysis of the correlation between these two scores and a general cognitive assessment of executive function, working, episodic (i.e. new learning ability) and semantic memory, and behavioural changes highlighted the considerable involvement of executive function, semantic memory and, to a lesser degree, episodic memory and behavioural changes. Moreover, step-wise regression analyses performed on the EM score revealed that the executive function was a better predictor of the retrograde component than of the anterograde component, which was linked principally to new episodic learning ability. All these results confirm the impact of executive dysfunction on autobiographical deficits in fv-FTD, and suggest that the mechanisms at the root of autobiographical memory disruption may also involve difficulties in new episodic learning and semantic storage, though this may be due to the fact that we studied an advanced form of fv-FTD.