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Parathyroid carcinoma (PCA), accounting for less than one per cent of all endocrine malignancies, is a rare cause of primary hyperparathyroidism. A diagnosis of parathyroid carcinoma may be challenging in the presence of localised disease and involves a histological diagnosis based on capsular, vascular, or perineural invasion or the presence of metastasis. Distant metastasis remains a rare presentation, with the lung being the most common site. Surgery remains the treatment of choice as radiotherapy and chemotherapy have proved to be of limited benefit in metastatic disease. This case reports suggests that radiofrequency ablation has the potential to be a novel and effective treatment option in these patients.  相似文献   
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Increasing number of Phase I/II clinical studies have demonstrated clinical potential of curcumin for treatment of various types of human cancers. Despite significant anti-tumor efficacies and bio-safety profiles of curcumin, poor systemic bioavailability is retarding its clinical success. Efforts are now being directed toward developing stable formulations of curcumin using various drug delivery systems. To this end, herein we report on the development of a new tumor vasculature targeting liposomal formulation of curcumin containing a lipopeptide with RGDK-head group and two stearyl tails, di-oleyolphosphatidylcholine (DOPC) and cholesterol. We show that essentially water insoluble curcumin can be solubilized in fairly high concentrations (~ 500 μg/mL) in such formulation. Findings in the Annexin V/Propidium iodide (PI) binding based flow cytometric assays showed significant apoptosis inducing properties of the present curcumin formulation in both endothelial (HUVEC) and tumor (B16F10) cells. Using syngeneic mouse tumor model, we show that growth of solid melanoma tumor can be inhibited by targeting such liposomal formulation of curcumin to tumor vasculature. Results in immunohistochemical staining of the tumor cryosections are consistent with tumor growth inhibition being mediated by apoptosis of tumor endothelial cells. Findings in both in vitro and in vivo mechanistic studies are consistent with the supposition that the presently described liposomal formulation of curcumin inhibits tumor growth by blocking VEGF-induced STAT3 phosphorylation in tumor endothelium. To the best of our knowledge, this is the first report on inhibiting tumor growth through targeting liposomal formulation of curcumin to tumor vasculatures.  相似文献   
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Infectious mononucleosis and B-cell transformation in response to infection with Epstein–Barr virus (EBV) is dependent upon binding of the EBV envelope glycoprotein gp350 to CD21 on B-cells. Gp350-specific antibody comprises most of the EBV neutralizing activity in the serum of infected patients, making this protein a promising target antigen for a prophylactic EBV vaccine. We describe a novel, tetrameric gp350-based vaccine that exhibits markedly enhanced immunogenicity relative to its monomeric counterpart. Plasmid DNA was constructed for synthesis, within transfected CHO cells, of a tetrameric, truncated (a.a. 1–470) gp350 protein (gp3501–470). Tetrameric gp3501–470 induced ∼20-fold higher serum titers of gp3501–470-specific IgG and >19-fold enhancements in neutralizing titers at the highest dose, and was >25-fold more immunogenic on a per-weight basis than monomeric gp3501–470. Further, epidermal immunization with plasmid DNA encoding gp3501–470 tetramer induced 8-fold higher serum titers of gp3501–470-specific IgG relative to monomer. Tetrameric gp3501–470 binding to human CD21 was >24-fold more efficient on a per-weight basis than monomer, but neither tetramer nor monomer mediated polyclonal human B-cell activation. Finally, the introduction of strong, universal tetanus toxoid (TT)-specific CD4+ T-cell epitopes into the tetrameric gp3501–470 had no effect on the gp3501–470-specific IgG response in naïve mice, and resulted in suppressed gp3501–470-specific IgG responses in TT-primed mice. Collectively, these data suggest that tetrameric gp3501–470 is a potentially promising candidate for testing as a prophylactic EBV vaccine, and that protein multimerization, using the approach described herein, is likely to be clinically relevant for enhancing the immunogenicity of other proteins of vaccine interest.  相似文献   
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Introduction

In spite of having BCG vaccination and tuberculosis control program for the last 50 years, prevalence of tuberculosis continues to be high in India. Inadequate diagnostic methods, suboptimal treatment and monitoring, and the lack of vigilant reporting system are some of the contributing factors for the failure of TB control.

Objectives

To know the current practices among local pediatricians regarding management of TB.

Materials and methods

Field based cross sectional study. All the registered pediatricians who were practicing in Mangalore, (list – local IAP branch) were included in the study. A structured Questionnaire on signs and symptoms of TB, diagnosis, strategies adopted in treatment, MDR tuberculosis and reporting of cases to RNTCP was asked. Management practice standards according to the Updated National Guidelines for Pediatric Tuberculosis in India, 2012, RNTCP guidelines in consensus with IAP, latest at the time of the study.

Results

50 pediatricians participated in the study with 62% having an attachment to the teaching institution. More than 50% identified all the symptoms of TB. 64% were sending chest X-ray, Mantoux test and gastric lavage/induced sputum examination for AFB to diagnose TB. 22% were not stressing for AFB examination. Still 16% told serological tests as one of the diagnostic modality. 52% were not aware about the diagnosis of latent TB. In 16% of their cases ATT was on a trial basis. Only 52% of the clinicians are adhering to updated national (RNTCP) guidelines. 30% felt still there are drawbacks in the current RNTCP guidelines. 72% knew the correct definition of MDR tuberculosis. But only 36% of them knew the diagnostic method (gene expert/CB NAAT) of confirming the MDR TB.

Conclusion

Management practices are found to be still suboptimum. Better engagement of the private sector is urgently required to improve TB management practices and to prevent diagnostic delay and drug resistance.  相似文献   
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Thyroid hormone is critical for central nervous system development. Fetal hypothyroidism leads to reduced cognitive performance in offspring as well as other effects on neural development in both humans and experimental animals. The nature of these impairments suggests that thyroid hormone may exert its effects via dysregulation of the neurotrophin brain-derived neurotrophic factor (BDNF), which is critical to normal development of the central nervous system and has been implicated in neurodevelopmental disorders. The only evidence of BDNF dysregulation in early development, however, comes from experimental models in which severe prenatal hypothyroidism occurred. By contrast, milder prenatal hypothyroidism has been shown to alter BDNF levels and BDNF-dependent functions only much later in life. We hypothesized that mild experimental prenatal hypothyroidism might lead to dysregulation of BDNF in the early postnatal period. BDNF levels were measured by ELISA at 3 or 7 d after birth in different regions of the brains of rats exposed to propylthiouracil (PTU) in the drinking water. The dose of PTU that was used induced mild maternal thyroid hormone insufficiency. Pups, but not the parents, exhibited alterations in tissue BDNF levels. Hippocampal BDNF levels were reduced at both d 3 and 7, but no significant reductions were observed in either the cerebellum or brain stem. Unexpectedly, more males than females were born to PTU-treated dams, suggesting an effect of PTU on sex determination. These results support the hypothesis that reduced hippocampal BDNF levels during early development may contribute to the adverse neurodevelopmental effects of mild thyroid hormone insufficiency during pregnancy.  相似文献   
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