Duodenum-preserving pancreatic head resection in solid pseudopapillary neoplasm—Report of a case

INTRODUCTION

Solid pseudopapillary neoplasm (SPPN) was first characterized by Virginia Frantz in 1959. The duodenum-preserving pancreatic head resection (DPPHR) has been described as treatment for low-grade malignant tumors of the head of the pancreas including eight cases of SPPN.PRESENTATION OF CASE: A 16-year-old white female patient presented with abdominal pain and dyspepsia. Computed tomography scan of abdomen showed a 10 × 9 × 10 cm³ lesion on the pancreatic head. After radiological diagnosis of SPPN the patient was submitted to DPPHR. Resection was achieved with clear margins. Immunohistochemical study demonstrated positivity for progesterone receptor, β-catenin, cytoplasmic paranuclear dot-like CD99, negativity for chromogranin and S100 protein and Ki 67 index of 1%.

DISCUSSION

A large encapsulated pancreatic mass with well-defined borders that contains areas of calcifications and intratumoral hemorrhage on CT scan in a young female is virtually diagnostic of an SPPN. A particular dot-like intracytoplasmic expression of CD99 appears to be highly unique for SPPN

CONCLUSION

DPPHR should be considered in cases of SPPN in the pancreas head if there is no compromise with oncologic radicality.     

Recent synthetic efforts in the preparation of 2-(3,4)-alkenyl (aryl) quinoline molecules towards anti-kinetoplastid agents

Leishmaniasis, Chagas disease and African sleeping sickness have been considered some of the most important tropical protozoan afflictions. As the number of drugs currently available to treat these human illnesses is severely limited and the majority has poor safety profiles and complicated administration schedules, actually there is an urgent need to develop new effective, safe and cost-effective drugs. Because quinoline alkaloids with antiprotozoal activity (quinine, chimanine, cryptolepine or huperzine groups) were historically and are still essential models for drug research to combat these parasitic infections, synthetic or semi-synthetic quinoline-based molecules are important for anti-kinetoplastid drug design approaches and synthetic methods of their preparation become a key task that is the central subject of this review. Its goal is to highlight the advances in the conventional and current syntheses of new 2-(3,4)-alkenyl (aryl) quinoline derivatives, which kill the most important kinetoplastid protozoa, – Leishmania and Trypanosoma and could be useful models for antileishmanial and antitrypanosomal research. An attempt has been made to present and discuss the more recent contributions in this field over the period 2015–2019, paying special attention to molecular design, synthetic efforts to new green reaction conditions for classical methods such as Skraup synthesis, Friedländer synthesis, Conrad–Limpach, Doebner–Miller, as well as contemporary methods like Gould–Jacobs, Meth–Cohn and Povarov reactions. This review includes brief general information on these neglected tropical diseases, their current chemotherapies, and primary natural models (quinoline alkaloids), suitable for development of anti-kinetoplastid quinoline-based agents. The main part of the review comprises critical discussion on the synthesis and chemistry of new quinolines diversely substituted by alkyl (alkenyl, aryl) fragments on the pyridine part of the quinoline skeleton, which could be considered interesting analogues of chimanine alkaloids. The methods described in this review were developed with the aim of overcoming the drawbacks of the traditional protocols using revolutionary precursors and strategies.

Leishmaniasis, Chagas disease and African sleeping sickness have been considered some of the most important tropical protozoan afflictions.     

Characterization of a Parkinson’s disease rat model using an upgraded paraquat exposure paradigm

Animal models of human diseases are crucial experimental tools to investigate the mechanisms involved in disease pathogenesis and to develop new therapies. In spite of the numerous animal models currently available that reproduce several neuropathological features of Parkinson disease (PD), it is challenging to have one that consistently recapitulates human PD conditions in both motor behaviors and biochemical pathological outcomes. Given that, we have implemented a new paradigm to expose rats to a chronic low dose of paraquat (PQ), using osmotic minipumps and characterized the developed pathologic features over time. The PQ exposure paradigm used lead to a rodent model of PD depicting progressive nigrostriatal dopaminergic neurodegeneration, characterized by a 41% significant loss of dopaminergic neuron in the substantia nigra pars compacta (SNpc), a significant decrease of 18% and 40% of dopamine levels in striatum at week 5 and 8, respectively, and a significant 1.5‐fold decrease in motor performance. We observed a significant increase of microglia activation state, sustained levels of α‐synucleinopathy and increased oxidative stress markers in the SNpc. In summary, this is an explorative study that allowed to characterize an improved PQ‐based rat model that recapitulates cardinal features of PD and may represent an attractive tool to investigate several mechanisms underlying the various aspects of PD pathogenesis as well as for the validation of the efficacy of new therapeutic approaches that targets different mechanisms involved in PD neurodegeneration.     

Papillary tumor of the pineal region: Case report and review of the literature

Papillary tumor of the pineal region is a rare neuroepithelial tumor characterized by papillary architecture and epithelial cytology, immunopositivity for cytokeratin and ependymal differentiation. It is considered grade II–III by the World Health Organization and was first described by Jouvet in 2003. We present a 34-year-old male with headaches, blurred vision and normal examination. Radiological study showed a nodulocystic lesion in the pineal region compatible with pineocytoma. Surgery was performed using an infratentorial supracerebellar approach, finding a cystic tumor in the quadrigeminal cistern which was completely resected. Histopathology reported a papillary tumor of the pineal region. The patient made good progress without adjuvant therapy, and after 57 months of follow-up he remained asymptomatic and free of recurrence. A review of the literature was performed to collect all the cases published with gross total resection and no complementary treatment. In conclusion, there is still much to be learned about the pathogenesis, prognosis and management of this tumor.     

牙列缺损的计算机三维建模

目的 建立牙列缺损的计算机三维模型。方法 采用表面绘制法,依据CT扫描头颅骨标本获得的二维断层图像数据在3D Studio Max中沿牙体长轴放样、微调并赋以材质,得到牙列缺损的计算机三维模型。结果 能在计算机中方便快速地模拟任意类型的牙列缺损,并可全方位地旋转、放大和缩小。结论 提供了一种牙列缺损三维建模的新方法,有利于三维义齿专家系统的开发和计算机辅助教学。     

From regenerative strategies to pharmacological approaches:can we fine-tune treatment for Parkinson's disease?

Parkinson's disease is the second most prevalent neurodegenerative disorder worldwide.Clinically,it is characterized by severe motor complications caused by progressive degeneration of dopaminergic neurons.Current treatment is focused on mitigating the symptoms through the administration of levodopa,rather than on preventing dopaminergic neuronal damage.Therefore,the use and development of neuroprotective/disease-modifying strategies is an absolute need that can lead to promising gains on translational research of Parkinson's disease.For instance,N-acetylcysteine,a natural compound with strong antioxidant effects,has been shown to modulate oxidative stress,preventing dopamine-induced cell death.Despite the evidence of neuroprotective and modulatory effects of this drug,as far as we know,it does not induce per se any regenerative process.Therefore,it would be of interest to combine the latter with innovative therapies that induce dopaminergic neurons repair or even differentiation,as stem cell-based strategies.Stem cells secretome has been proposed as a promising therapeutic approach for Parkinson's disease,given its ability to modulate cell viability/preservation of dopaminergic neurons.Such approach represents a shift in the paradigm,showing that cell-transplantation free therapies based on the use of stem cells secretome may represent a potential alternative for regenerative medicine of Parkinson's disease.Thus,in this review,we address the current understanding of the potential combination of stem cell free-based strategies and neuroprotective/disease-modifying strategies as a new paradigm for the treatment of central nervous system neurodegenerative diseases,like Parkinson's disease.     

Chromosome banding analysis and genomic microarrays are both useful but not equivalent methods for genomic complexity risk stratification in chronic lymphocytic leukemia patients

Genome complexity has been associated with poor outcome in patients with chronic lymphocytic leukemia (CLL). Previous cooperative studies established five abnormalities as the cut-off that best predicts an adverse evolution by chromosome banding analysis (CBA) and genomic microarrays (GM). However, data comparing risk stratification by both methods are scarce. Herein, we assessed a cohort of 340 untreated CLL patients highly enriched in cases with complex karyotype (CK) (46.5%) with parallel CBA and GM studies. Abnormalities found by both techniques were compared. Prognostic stratification in three risk groups based on genomic complexity (0-2, 3-4 and ≥5 abnormalities) was also analyzed. No significant differences in the percentage of patients in each group were detected, but only a moderate agreement was observed between methods when focusing on individual cases (κ=0.507; P<0.001). Discordant classification was obtained in 100 patients (29.4%), including 3% classified in opposite risk groups. Most discrepancies were technique-dependent and no greater correlation in the number of abnormalities was achieved when different filtering strategies were applied for GM. Nonetheless, both methods showed a similar concordance index for prediction of time to first treatment (TTFT) (CBA: 0.67 vs. GM: 0.65) and overall survival (CBA: 0.55 vs. GM: 0.57). High complexity maintained its significance in the multivariate analysis for TTFT including TP53 and IGHV status when defined by CBA (hazard ratio [HR] 3.23; P<0.001) and GM (HR 2.74; P<0.001). Our findings suggest that both methods are useful but not equivalent for risk stratification of CLL patients. Validation studies are needed to establish the prognostic value of genome complexity based on GM data in future prospective studies.