Brain metastases as primary manifestation of a melanocytic malignant peripheral nerve sheath tumor in a 60-year-old man

Background  

Malignant peripheral nerve sheath tumors are rare tumor entities that originate from peripheral nerve sheaths and have an unfavorable prognosis. Metastatic spread to the cerebral parenchyma is absolutely rare. This case report describes the clinical course in a 60-year-old man whose tumor came to medical attention because of a seizure.     

RETRACTED ARTICLE: A mathematical model to study the relationship between the dietary profiles,core body temperature and sleep profile in the high school students

Body temperature (T_b), food intake and sleep cycle follows a circadian rhythm. Circadian variations of T_b may be influenced by changes in sleep time, late night consumption of high calorie diet and less physical activities. Deviations in any of these daily habits may alter the acrophase, mesor and amplitude of the cosinor curve of T_b. Changes in these confounding factors may also contribute to the body mass index (BMI) of the individual. This study was conducted on 29 high school going adolescents. We have employed an ideal cosinor model to study the changes in the 24 h cyclical changes in T_b (n = 12). Academic overload during examination days was seen in these high school going adults. Sleep duration and dietary habits were also studied in them to find out the relationship with BMI and circadian variations if any (n = 17). Higher BMI was observed in individuals having shorter sleep duration. BMI was high in students consuming high calorie diet at the time of the day when the body metabolism is normally low. A mathematical model exhibiting altered circadian rhythms is proposed that may be used to modify strategies to restore biorhythms for better health.

     

Molecular structure in peripheral dog breeds: Portuguese native breeds as a case study

Genetic variability in purebred dogs is known to be highly structured, with differences among breeds accounting for ∼30% of the genetic variation. However, analysis of the genetic structure in non-cosmopolitan breeds and local populations is still limited. Nine Portuguese native dog breeds, and other peripheral dog populations (five) with regional affinities, were characterized using 16 microsatellites and 225 amplified fragment length polymorphism (AFLP) markers, and the pattern of genetic differentiation was investigated. Although the level of breed differentiation detected is below that of other dog breeds, there is in most cases a correlation between breed affiliation and molecular structure. AFLP markers and Bayesian clustering methods allowed an average of 73.1% of individuals to be correctly assigned to source populations, providing robust genotypic assessment of breed affiliation. A geographical genetic structure was also detected, which suggests a limited influence of African dogs on the Iberian breeds. The sampling effect on the estimation of population structure was evaluated and there was a 2.2% decrease in genetic differentiation among breeds when working animals were included. Genetic diversity of stray dogs was also assessed and there is no evidence that they pose a threat to the preservation of the gene pool of native dog breeds.     

Evaluation of myelin sheath and collagen reorganization pattern in a model of peripheral nerve regeneration using an integrated histochemical approach

Peripheral nerves are complex histological structures that can be affected by a variety of conditions with different degree of axonal degeneration and demyelination. For the study of peripheral nerve regeneration in pathology and tissue engineering, it is necessary to evaluate the regeneration, remyelination and extracellular matrix reorganization of the neural tissue. Currently, different histochemical techniques must be used in parallel, and a correlation among their findings should be further performed. In this work, we describe a new histochemical method for myelin and collagen fibers based on luxol fast blue and picrosirius methods, for the evaluation of the morphology, the myelin sheath and the collagen fiber reorganization using a model of peripheral nerve regeneration. Whole brain, normal sciatic nerve and regenerating peripheral nerve samples were fixed in 10% neutral buffered formalin and paraffin-embedded, for the performance of the hematoxylin-eosin stain, the Luxol fast blue method and the new histochemical method for myelin and collagen. The results of this technique revealed that this new histochemical method allowed us to properly evaluate histological patterns, and simultaneously observe the histochemical reaction for myelin sheath and collagen fibers in normal tissue, and during the regeneration process. In conclusion, this new method combines morphological and histochemical properties that allowed us to determine with high accuracy the degree of remyelination and collagen fibers reorganization. For all these reasons, we hypothesize that this new histochemical method could be useful in pathology and tissue engineering.     

人脑对不同频率穴位电刺激反应的功能性磁共振成像

利用功能性磁共振方法研究人脑对不同频率穴位体表电刺激（transcutaneous electric nerve stimulation,TENS)的反应。实验对11名志愿得进行了22次脑部功能性磁共振成像。成像过程中,每名志愿者分别接受了2和100HzTENS刺激,刺激部位为左腿足三里和三阴交穴,结果为不同频率TENS都激活了初级和次级躯体感觉区,频率特异性的激活信号出现在与运动相关的区域、丘脑、边缘系统和联络皮层。结果显示,在相同穴位给予不同频率的TENS要以在大脑引起不同的反应,提示2和100HzTENS可能激活了不同的神经通路,这些神经通路分别在中枢神经系统起着不同的作用。     

Epithelial myoepithelial carcinoma of the parotid gland with malignant ductal and myoepithelial components arising in a pleomorphic adenoma: a case report with cytologic, histologic and immunohistochemical correlation

BACKGROUND: To describe the cytologic, histologic and immunohistochemical findings of a case of epithelial myoepithelial carcinoma (EMC) arising from a pleomorphic adenoma (PA) of the parotid with both malignant epithelial and myoepithelial components. CASE: A 29-year-old female presented with a 1.5 x 1.5-cm, palpable mass of the left parotid of 7-8 months' duration with recent enlargement and pain. Fine needle aspiration biopsy (FNAB) revealed biphasic epithelial (small cell) and myoepithelial (large/clear cell) clusters arranged in a pseudopapillary and trabecular pattern with abundant hyaline material with many naked nuclei, together with areas typical of pleomorphic adenoma (PA) was noted. The cytology was reported as salivary gland neoplasm, "suggestive of adenoid cystic carcinoma, less likely pleomorphic adenoma." The mass was excised and histologically reported as "pleomorphic adenoma, with focal invasion of one resected margin." Four months later the tumor recurred, and FNAB showed almost the same cytologic features as did the previous aspirate. Due to early recurrence, previous histologic sections were reviewed, and typical areas of a biphasic pattern of EMC with atypicality and mitosis of both components was found. The final diagnosis was EMC ex PA. CONCLUSION: Although previous reports mention the difficulties in diagnosing EMC and differentiation from the more common salivary gland neoplasms such as PA, we like to emphasize the cytologic confusion that results when the tumors coexist.     

Identification of miRNA-103 in the cellular fraction of human peripheral blood as a potential biomarker for malignant mesothelioma--a pilot study

Background

To date, no biomarkers with reasonable sensitivity and specificity for the early detection of malignant mesothelioma have been described. The use of microRNAs (miRNAs) as minimally-invasive biomarkers has opened new opportunities for the diagnosis of cancer, primarily because they exhibit tumor-specific expression profiles and have been commonly observed in blood of both cancer patients and healthy controls. The aim of this pilot study was to identify miRNAs in the cellular fraction of human peripheral blood as potential novel biomarkers for the detection of malignant mesothelioma.

Methodology/Principal Findings

Using oligonucleotide microarrays for biomarker identification the miRNA levels in the cellular fraction of human peripheral blood of mesothelioma patients and asbestos-exposed controls were analyzed. Using a threefold expression change in combination with a significance level of p<0.05, miR-103 was identified as a potential biomarker for malignant mesothelioma. Quantitative real-time PCR (qRT-PCR) was used for validation of miR-103 in 23 malignant mesothelioma patients, 17 asbestos-exposed controls, and 25 controls from the general population. For discrimination of mesothelioma patients from asbestos-exposed controls a sensitivity of 83% and a specificity of 71% were calculated, and for discrimination of mesothelioma patients from the general population a sensitivity of 78% and a specificity of 76%.

Conclusions/Significance

The results of this pilot study show that miR-103 is characterized by a promising sensitivity and specificity and might be a potential minimally-invasive biomarker for the diagnosis of mesothelioma. In addition, our results support the concept of using the cellular fraction of human blood for biomarker discovery. However, for early detection of malignant mesothelioma the feasibility of miR-103 alone or in combination with other biomarkers needs to be analyzed in a prospective study.     

Effect of diabetes on collagen metabolism and hypoxia in human gingival tissue: a stereological,histopathological, and immunohistochemical study

Diabetes mellitus and periodontitis are chronic inflammatory diseases that disrupt soft tissue metabolism. The diseases separately or together increase apoptosis in gingival fibroblast cells and reduce cell renewal. We investigated the effects of diabetes and periodontitis on the composition and structure of gingival connective tissue. We used gingival biopsies from 16 healthy individuals (control group, C), 16 type 2 diabetic patients with chronic periodontitis (diabetes + periodontitis group, D + P) and 16 healthy chronic periodontitis patients (periodontitis group, P). Biopsies were obtained under local anesthesia. Clinical attachment level (CAL), gingival index (GI) and plaque index (PI) were measured prior to gingival biopsies. Fibroblast cells were counted stereologically. Inflammatory cells were counted histomorphometrically. Hypoxia-inducible factor (HIF)-1α, lysyl hydroxylase (PLOD-2), neutrophil collagenase (MMP-8), and vascular endothelial growth factor (VEGF) levels were evaluated immunohistochemically. CAL, GI and PI for the C group were lower than for the other groups (p < 0.05). Fibroblast cell counts were lower for the D + P group than for the other groups (p < 0.05). Diabetes increased inflammatory cell numbers in the D and D + P groups compared to the C and P groups. MMP-8 levels were higher for the D + P group than for the other groups. VEGF was elevated in both the P and D + P groups compared to the C group, while HIF-1α and PLOD-2 levels were comparable. Diabetes increased tissue destruction and inflammation, and decreased fibroblast cell numbers without affecting collagen crosslinking and HIF-1α levels.     

Differential expression of annexins I, II and IV in human tissues: an immunohistochemical study

 Annexins constitute a family of Ca²⁺- and phospholipid-binding proteins. Although their functions are still not clearly defined, several members of the annexin family have been implicated in membrane-related events along exocytotic and endocytotic pathways. To elucidate a possible correlation of those functional proposals with the tissue distribution of annexins, we analysed immunohistochemically the expression of annexins I, II and IV in a broad variety of human tissues. Annexins I and II were chosen for this study since their functionally relevant N-terminal domains are structurally closely related, whilst annexin IV is structurally less related to the former two proteins. The study revealed distinct expression patterns of annexins I, II and IV throughout the body. Annexin I was found in leucocytes of peripheral blood, tissue macrophages and T-lymphocytes and in certain epithelial cells (respiratory and urinary system, superficial cells of non-keratinised squamous epithelium), annexin II in endothelial cells, myoepithelial cells and certain epithelial cells (mainly respiratory and urinary system), whereas annexin IV was almost exclusively found in epithelial cells. Epithelia of the upper respiratory system, Bowman’s capsule, urothelial cells, mesothelial cells, peripheral nerves, the choroid plexus, ependymal cells and pia mater and arachnoid of meninges generally strongly expressed all three annexins investigated. The characteristic expression in different tissues and the intracellular distribution indicates that the three annexins investigated are involved in aspects of differentiation and/or physiological functions specific to these tissues. Accepted: 15 January 1998     

Coculture of human articular chondrocytes with peripheral blood mononuclear cells as a model to study cytokine-mediated interactions between inflammatory cells and target cells in the rheumatoid joint

Summary A model for the coculture of chondrocytes in gelified agarose with mononuclear cells was developed to serve as an in vitro equivalent for cytokine-mediated events at the cartilage-synovial pannus junction in destructive arthropathies. Chondrocytes cultured in agarose keep their phenotypic stability. They release cartilage-specific aggrecans into the surrounding artificial matrix. When activated with lipopolysaccharide for 1 h, mononuclear cells release Interleukin 1β and Tumor Necrosis Factorα, thereby stimulating the chondrocytes to produce Interleukin 6, to diminish incorporation of³⁵S into aggrecans, and to degrade these intercellular macromolecules. This coculture model is a useful tool for studying interactions between inflammatory cells and target cells. To demonstrate its usefulness, the effect of three anti-inflammatory drugs (piroxicam, sulphasalazine, and hydrocortisone) on cytokine release by mononuclear cells, and subsequently on chondrocyte aggrecan metabolism was studied. The drugs were unable to abrogate Interleukin 1 and Tumor Necrosis Factorα release by activated mononuclear cells. Therefore, these pharmacological agents did not protect the artificial target tissue against cytokine-mediated degradation.     

Balloon expansion of the pectoralis major muscle flap in sternoplasty: a biomechanical and histologic study in a rat model

The pectoralis major advancement flap is currently the most popular technique for reconstruction of the anterior chest in patients with sternotomy wounds. Recently, the SpaceMaker balloon was introduced for rapid expansion of the pectoralis major muscle intraoperatively. The aim of the present study was to investigate the biomechanical and histologic effects of this expansion technique in a rat model. The upper 2 cm of the sternum was resected in 54 male rats. Reconstruction with balloon-assisted pectoralis muscle expansion was performed in 24 rats (study group). Another 24 rats underwent reconstruction with simple muscle advancement without expansion. Submuscular insertion of a catheter for expansion, without inflation, was performed in the remaining six rats (sham group). Rats were killed either immediately or 2 to 4 weeks after surgery. Thirty-eight rats, including 16 after reconstruction with expansion, 16 after reconstruction without expansion, and six in the sham group, were killed immediately after surgery. Sixteen rats were killed 2 to 4 weeks after surgery, eight rats for each reconstruction technique. Before the animals were killed, the biomechanical properties of the muscles were tested with weights to calculate stiffness (in newtons per meter) and compliance gain (in percent). After the animals were killed, biopsy specimens were obtained for histologic analysis. Results indicated significantly lower muscle stiffness in the study group compared with the others immediately after surgery (p = 0.0000), although the difference failed to achieve statistical significance 2 to 4 weeks later (p = 0.76). In the study group, the compliance gain was 74.4 percent immediately after surgery but only 3.4 percent 2 weeks to 1 month postoperatively. Histologic examinations in all groups immediately and 2 to 4 weeks after surgery revealed regular muscle striation with no signs of inflammation. The elastic stiffness of the rat pectoralis major muscle is significantly reduced following rapid intraoperative expansion and returns to normal 2 to 4 weeks later.