Sensory evoked potentials in patients with Rett syndrome through the lens of animal studies: Systematic review

ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.     

生长抑素及其类似物联合质子泵抑制剂应用于急性非静脉曲张性上消化道出血的循证分析

目的 系统评价生长抑素及其类似物联合质子泵抑制剂（proton pump inhibitor，PPI）治疗急性非静脉曲张性上消化道出血（acute non-variceal upper gastrointestinal bleeding，ANVUGIB）的有效性和安全性，并分析其用药经济性。方法 采用循证医学方法搜集生长抑素及其类似物联合PPI治疗ANVUGIB的RCT、队列研究进行meta分析，得到相应的有效性及安全性分析结果，并进行成本-效果分析。结果 最终纳入6个RCT均未接受内镜治疗，共610例受试者。Meta分析结果显示，生长抑素及其类似物联合高、中、低剂量PPI治疗在以下方面均优于单用高、中、低剂量PPI治疗，差异有统计学意义，总有效率[OR=3.34，95%CI（2.03，5.47），P<0.000 01]、止血时间[MD=-9.04，95%CI（-11.69，-6.38），P<0.000 01]、输血量[MD=-1.10，95%CI（-1.46，-0.74），P<0.000 01]；在不良反应发生率方面，2组差异无统计学意义[OR=0.49，95%CI（0.11，2.12），P=0.34]。ANVUGIB患者予生长抑素联合高、中、低剂量奥美拉唑与单用高、中、低剂量奥美拉唑进行成本-效果分析，增量成本效果比分别为172.28，217.26，330.37，敏感性分析后显示结果稳定。而接受内镜治疗后应用生长抑素及其类似物联合PPI治疗仅1个队列研究，研究结果显示内镜治疗成功后联合治疗并不优于PPI单药治疗。结论 现有证据表明，生长抑素及其类似物联合PPI治疗未经内镜治疗的ANVUGIB患者为较有效的方案，两者安全性相当、耐受性较好，从药品直接成本考虑，高剂量PPI组联合治疗较中、低剂量PPI组联合治疗更具有成本效果性。而对于经内镜下止血治疗的患者两者疗效相当，可考虑单用PPI。     

Ablation of striatal somatostatin interneurons affects MSN morphology and electrophysiological properties,and increases cocaine‐induced hyperlocomotion in mice

The striatum is mainly composed by medium spiny neurons (95 %) (MSNs). Although outnumbered, in other brain regions such as the hippocampus and the cortex, somatostatin interneurons (SSTi) are known to control and fine‐tune the activity of principal cells. This information is still fragmented for the striatum. Here, we questioned the striatal functional consequences of the selective ablation of SSTi in the striatum at the behavioural and cellular levels. We identified increased excitability coupled with decreased distal spine density in MSNs from SSTi‐ablated mice. Although the ethological behavioural analysis did not reveal differences between the groups, SSTi‐ablated mice were significantly more sensitive to the locomotor effects of cocaine without changes in motivation. This was accompanied by increased expression of the dopamine transporter (DAT) in the ventral striatum. Altogether, we show that SSTi are important players in the maintenance of MSN excitability and spine density impacting on mechanisms towards hyperdopaminergic states.     

Inhibitory neuronal changes following a mixed diffuse-focal model of traumatic brain injury

Traumatic brain injury (TBI) can result in excitation: inhibition imbalance, as well as a range of chronic neurological deficits. However, how TBI affects different interneurons, and how this relates to behavioral abnormalities, remains poorly understood. This study examined the effects of a mixed diffuse-focal model of TBI, the lateral fluid percussion injury (LFPI), on interneurons, 8 weeks post-TBI in rats. Brains were labeled with antibodies against calbindin, parvalbumin, calretinin, neuropeptide Y, and somatostatin, and the number of interneurons were assessed in the cortex and hippocampus following LFPI. LFPI caused a reduction in the numbers of interneurons mediating both perisomatic and dendritic inhibition in the somatosensory cortex. In hippocampus, there were heterogenous changes in the number of interneurons while motor cortex, showed no obvious loss in any of the subsets of interneurons after TBI. In parallel to the investigations of changes in the number of interneurons, we also investigated the long-term behavioral consequences of LFPI. Behaviorally, rats given an LFPI displayed transient reduction in performance in motor tasks and were significantly impaired in reversal learning in the water maze task post-TBI. We also report here progressive neurodegeneration in cortex and hippocampus indicated by Fluoro-Jade C in the different brain areas examined after injury. Our findings suggest differential vulnerability of inhibitory neurons to LFPI in the different brain areas examined after injury. These data will aid in evaluation of new treatments for TBI and help target specific neuronal subtypes as a function of injury time and type.     

Octreotide long-acting release (LAR) in combination with other therapies for treatment of neuroendocrine neoplasia: a systematic review

BackgroundIn the last decades, the incidence of neuroendocrine neoplasia (NEN) increased from 1 to 5 new diagnoses/100,000 persons/year. The synthetic somatostatin analogues (SSAs) represent the first-choice treatment for both functionally active and inactive gastro-enteric-pancreatic NEN. This systematic review examines the role of octreotide long-acting release (LAR) in combination with other therapies for NEN management.MethodsPrimary outcomes were the disease control rate and the progression free survival (PFS), defined as the time between treatment initiation and progression of disease. Secondary outcomes were overall survival (OS) and safety.ResultsThis systematic review identified 13 studies, concerning the use of octreotide LAR in association with other therapies in advanced NENs and included 1,206 patients. Patients were treated with octreotide LAR in combination with other drugs, mainly with everolimus (404 patients, 35%), but even with Peptide Receptor Radionuclide Therapy, bevacizumab, interferon or fluoride-derivatives. Disease control was observed in 85% cases with SSAs in combination with other therapies; PFS ranged from 15 to 16.4 months and OS from 25 to 61.9 months. SSAs are very well tolerated drugs, with few side effects which are usually mild, not requiring drug withdrawn.ConclusionsThe review summarizes the effectiveness and available safety data on octreotide LAR in combination with other therapies in patients with NEN and may provide suggestions to address the therapeutic strategy. Further comparative head-to-head studies are needed to understand which is the best combination treatment for patients with progressive NEN after failure of first-line therapy.     

99Tcm-octreotide显像对乳腺癌诊断的初步临床应用

目的 探讨用99锝m-奥曲肽(99Tcm-octreotide)显像对乳腺癌诊断的临床应用价值。方法 选择21例临床拟诊乳腺癌患者术前进行乳腺99Tcm-octreotide显像及B超检查,并与术后病理诊断对照分析。乳腺内或/和腋窝淋巴区域内见局部异常放射性浓聚为99Tcm-octreotide显像阳性。结果 21例患者中16例手术证实为乳腺癌,5例为良性病变。99Tcm-octreotide显像诊断乳腺癌的灵敏度、特异性和准确性分别为93.8%、80.0%和90.5%,其诊断特异性明显高于B超检查(P<0.01),但灵敏度和准确性二种方法无显著性差异(P>0.05)。结论 99Tcm-octreotide显像在乳腺癌的诊断中具有较高的准确性,对于乳腺肿瘤手术方案的制定也有一定的临床应用价值。     

生长激素联合生长抑素对重症急性胰腺炎细胞免疫的影响

目的：探讨联合应用八肽生长抑素（善宁）、生长激素（思增）治疗重症急性胰腺炎（SAP）对机体细胞免疫功能的影响。方法：36例重症急性胰腺炎随机分为对照组（n=12），单用八肽生长抑素（善宁组，n=12），联合应用善宁和生长激素（联合组，n=12）。比较3组病人d1、d14血浆中CD4、cd8阳性细胞百分比，CD4／CD8比值，住院天数、并发症发生率和病死率。结果：联合组并发症发生率明显低于善宁组及对照组（P〈0．05）；联合组d14 CD4阳性细胞百分比、CD4／CD8值高于单用善宁组和对照组（P〈0．05）。结论：联合应用生长抑素和生长激素改善SAP患者的细胞免疫功能。降低了临床并发症发生率。     

In vitro antiangiogenic activity of selective somatostatin subtype-1 receptor agonists

BACKGROUND: Endothelial cells of human blood vessels (arteries and veins) show high levels of somatostatin subtype-1 receptor (sst(1)). The aim of the present study is to investigate the inhibitory effects of novel somatostatin analogs, highly selective for human sst(1), on in vitro angiogenesis and their modulation of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR-2) expression. MATERIALS AND METHODS: Somatostatin analogs BIM-23745 and BIM-23926 were tested for their ability to prevent proliferation and migration of human endothelial HMEC-1 cells, to modulate VEGF and VEGFR-2 expression and to inhibit sprouting of microvessels from cultured human placental vessel explants in fibrin matrix for 28 days. RESULTS: The somatostatin sst(1 )receptor-selective agonists, BIM-23745 and BIM-23926 showed a suppression of endothelial proliferation (e.g. 10(-6) M BIM-23475, 40.0 +/- 2.1% vs. 100% of controls; 10(-7) M BIM-23926, 55.3 +/- 3.3% vs. 100% of controls), migration (e.g. 10(-7) M BIM-23475, 35.0 +/- 1.56% vs. 100% of controls; 10(-7) M BIM-23926, 53.7 +/- 1.77% vs. 100% of controls) and microvessel sprouting (e.g. 10(-8) M BIM-23475, 42.8 +/- 5.6% vs. 100% of controls; 10(-7) M BIM-23926, 17.2 +/- 11.8% vs. 100% of controls). A small but significant percentage of cells exposed to BIM-23745 and BIM-23926 for 24 h and for 72 h presented typical apoptotic morphology. Moreover, both the analogs significantly inhibit VEGF and VEGFR-2 gene expression in endothelial cells grown for 144 h in a fibrin matrix and the VEGF secretion in conditioned media. CONCLUSIONS: The inhibition of endothelial activities suggests potential therapeutic utility for administration of somatostatin sst(1 )receptor-selective agonists in the proliferative diseases involving angiogenesis.     

Somatostatin receptor 1–5; expression profiles during rat development

Background

Somatostatin acts through five receptor subtypes (SSTRs 1–5). We aimed to investigate SSTRs mRNA expression and protein distribution in whole rat embryos, with special emphasis on the pancreas.

Material and methods

Rat embryos were collected on embryonal days 10, 11, 12, 14, 15, 17, 19, 21, and at birth. Presence of SSTRs was investigated with RT-PCR techniques and immunohistochemistry.

Results

There was no SSTR5 mRNA expression in the whole rat embryos. All SSTR1–5 proteins were observed at embryonal day 10, but the localization varied between the different subtypes. From day 11 to birth SSTRs protein presence increased with time in major structures such as skin and cartilage. It remained similar over time in the heart and liver. In the fetal pancreas mRNA expression of SSTR2 and 4 was detected at day 14, and there was an increase up to birth. Only SSTR1 protein co-localized to a higher extent with the islet hormones studied. SSTR2 was present in all islet endocrine cells except for β-cells. In contrast, the immunostaining for SSTR3–4 was co-localized with insulin and PP, and, finally, SSTR5 with glucagon and pancreatic polypeptide. In mRNA isolated from whole rat embryos SSTR1-2 and SSTR4 expression showed a peak at day 14, while SSTR3 mRNA was not present until day 15.

Conclusion

The present data suggest a role for SSTRs during the development of the rat embryo. Subsequent functional studies may elucidate regulatory roles of specific SSTRs for the growth and differentiation of the pancreas as well as other organs.