Microwave irradiation increases recovery of neuropeptides from brain tissues

The effect of focused high energy microwave treatment (MW) on brain concentrations and molecular forms of substance P, neurokinin A, neuropeptide Y, neurotensin, galanin and calcitonin gene-related peptide was investigated. Groups of rats were treated as follows: 1) MW, storage for 60 min at 22°C, 2) Decapitation, storage for 60 min at 22°C, 3) Decapitation, storage for 60 min at 22°C, MW treatment, 4) MW, decapitation, storage for 2 min at 22°C and 5) Decapitation, storage for 2 min at 22°C. Peptide concentrations were in all instances highest in the MW sacrificed groups. MW increased the concentration of intact peptides by rapid inhibition of peptidase activity and increase in peptide solubility/extractability.     

Photochemical transformations and bacterial utilization of high-molecular-weight dissolved organic carbon in a southern Louisiana tidal stream (Bayou Trepagnier)

UVirradiation of dissolved organic carbon (DOC) in the laboratory can producesmall, labile organic compounds utilizable by microbes, but few studies haveattempted to document this process in situ. ¹³Cnuclear magnetic resonance (NMR) was used to examine the bulk chemicalcomposition of natural and laboratory-irradiated high-molecular-weight DOC(HMW-DOC) from shaded (150 mol m^–2s^–1 average light in surface water) and open (1500mol m^–2 s^–1) field sitesoverone and a half years. ¹³C NMR revealed only small differences incarbon functional groups between laboratory irradiated and non-irradiatedHMW-DOC. However, bacterial protein productivity per cell (BPP) was enhanced innaturally irradiated samples of HMW-DOC in a field mesocosm experiment (p <0.05), suggesting that bacterial growth was enhanced by photochemicalproductionof labile DOC substrates. Absorbance characteristics such as spectral slope,absorbance at 350 nm, and the absorbance ratio 250nm/365 nm revealed that HMW-DOC was photoreactive,yetno differences in these values were found between samples irradiated with andwithout UV-B. In experiments conducted with simulated solar radiation in thelaboratory and with natural light in the field mesocosm experiment, UV-A(320–400 nm) and photosynthetically active radiation (PAR;400–700 nm) were more effective than UV-B (280–320nm) in HMW-DOC photolysis.     

Composite Technique for Regional Neurochemical Studies: Measurement of Energy and Neurotransmitter Metabolites in Single Tissue Sample

A combined method is described for the determination of various metabolites from a single tissue sample of the brain. It comprises a quick inactivation of cerebral enzymes by microwave irradiation, easy separation of the desired brain regions, and perchloric acid extraction of tissue substances, which are assayed either by specific enzymatic techniques or by HPLC with electrochemical detection. The obtained values of most energy and neurotransmitter metabolites in the brain are in agreement with those reported using other methods. However, this technique, in contrast to the brain freezing in vitro or freeze-blowing, provides a more efficient procedure for rapid arrest of cerebral metabolism even in the deep brain structures and is therefore suitable for detection of early changes particularly those occurring in experimental pathological conditions such as ischemia.     

Identifying cell and molecular stress after radiation in a three-dimensional (3-D) model of oral mucositis

Mucositis is a debilitating adverse effect of chemotherapy and radiation treatment. It is important to develop a simple and reliable in vitro model, which can routinely be used to screen new drugs for prevention and treatment of mucositis. Furthermore, identifying cell and molecular stresses especially in the initiation phase of mucositis in this model will help towards this end. We evaluated a three-dimensional (3-D) human oral cell culture that consisted of oral keratinocytes and fibroblasts as a model of oral mucositis. The 3-D cell culture model was irradiated with 12 or 2 Gy. Six hours after the irradiation we evaluated microscopic sections of the cell culture for evidence of morphologic changes including apoptosis. We used microarrays to compare the expression of several genes from the irradiated tissue with identical genes from tissue that was not irradiated. We found that irradiation with 12 Gy induced significant histopathologic effects including cellular apoptosis. Irradiation significantly affected the expression of several genes of the NF-kB pathway and several inflammatory cytokines, such as IL-1B, 1L-8, NF-kB1, and FOS compared to tissue that was not irradiated. We identified significant upregulation of several genes that belong to damage-associated molecular patterns (DAMPs) such as HMB1, S100A13, SA10014, and SA10016 in the 3-D tissues that received 12 Gy but not in tissues that received 2 Gy. In conclusion, this model quantifies radiation damage and this is an important first step towards the development 3-D tissue as a screening tool.     

Degradation of hyaluronan by ultrasonication in comparison to microwave and conventional heating

Hyaluronan (hyaluronic acid, HA) was depolymerised by ultrasonication (US), microwave irradiation (MW) and conventional heating (CH), and the effect of pH and oxidants was investigated. The degradation was followed by viscometry and size exclusion chromatography coupled with low-angle light scattering. The results demonstrated that depolymerisation of HA by US leveled off to a limiting molecular mass, and the degradation was significantly enhanced by acidic and alkaline pH only in the presence of oxidants. In contrast to US, the course of depolymerisation by MW was strongly pH-dependent, and the degradation rate increased with decreasing pH. The expected enhancement of depolymerisation by MW in comparison to CH was marked only at very short heating time at pH <4. The NMR and FTIR spectral analyses indicated that HA in the whole M_w-range studied retained almost the backbone of the parent polysaccharide independently on the degradation method used. At harsh degradation conditions (long-term treatments, particularly at acidic pH or alkaline pH and in presence of oxidants) the depolymerisation was accompanied by destruction of both constituent sugar residues and formation of unsaturated structures detectable by UV-absorption at 230–240 and 260–270 nm. US-assisted oxidative degradation under mild reaction conditions was shown to be the most appropriate procedure to reduce the molecular mass of HA to 100 kDa without significant chemical modification of the polysaccharide.     

Synthesis of water-soluble multidentate aminoalcohol β-cyclodextrin derivatives via epoxide opening

New highly soluble β-aminoalcohol β-cyclodextrin (β-CD) derivatives have been synthesized via nucleophilic epoxide opening reactions with mono-6-amino mono-6-deoxy-permethyl-β-CD and mono-6-amino mono-6-deoxy-β-CD. The binding properties of the β-CD were enhanced by linking aminoalcohol subunits which caused its solubility to improve markedly. The reaction conditions were optimised using microwave irradiation giving moderate-to-good yields with a series of epoxides. A regioselective epoxide opening reaction was observed in the reaction with styrene oxide while the stereoselectivity was strictly dependent on substrate structure.     

干扰素阴道胶囊联合微波治疗宫颈炎合并高危型HPV感染对外周血Th17和Treg细胞及炎症因子的影响

目的探讨干扰素阴道胶囊联合微波治疗宫颈炎合并高危型人乳头瘤病毒(HPV)感染对外周血Th17和Treg细胞及炎症因子的影响。方法随机选择2015年1月-2018年1月在本院就诊的慢性宫颈炎合并高危型HPV感染患者90例,按随机数字表法分为观察组和对照组,每组45例。对照组给予重组人干扰素α2b栓,观察组给予重组人干扰素α2b栓联合微波治疗,治疗3个月后,观察两组患者的症状改善情况、HPV转阴率、血清炎性因子水平以及Th17和Treg细胞水平。结果观察组总有效为41例,占91.1%,对照组为73.3%,观察组显著高于对照组(P<0.05)。治疗后观察组的白带量改善率、白带脓性改善率、高危型HPV转阴率均显著高于对照组(P<0.05)。治疗前两组患者的白介素17(IL17)、肿瘤坏死因子β(TNFβ)、白介素23(IL23)水平比较,差异无统计学意义(P>0.05);治疗后两组患者的IL17、TNFβ、IL23水平均显著下降,且观察组下降更加显著(P<0.05)。治疗后观察组的Treg细胞、Th17细胞水平,Th17/Treg比值均较对照组低(P<0.05)。治疗前两组患者的滴虫、真菌、细菌性阴道炎、衣原体、解脲支原体感染人数比较差异无统计学意义(P>0.05),治疗后观察组的细菌性阴道炎、衣原体、解脲支原体感染显著降低,与对照组比较差异有统计学意义(P<0.05)。结论干扰素阴道胶囊联合微波治疗宫颈炎患者的治疗效果好,可显著改善患者症状,减轻体内炎症反应,增加HPV转阴率,调节Th17和Treg细胞,对预防宫颈癌有重要作用。     

Laser-induced Propagation and Destruction of Amyloid β Fibrils

The amyloid deposition of amyloid β (Aβ) peptides is a critical pathological event in Alzheimer disease (AD). Preventing the formation of amyloid deposits and removing preformed fibrils in tissues are important therapeutic strategies against AD. Previously, we reported the destruction of amyloid fibrils of β₂-microglobulin K3 fragments by laser irradiation coupled with the binding of amyloid-specific thioflavin T. Here, we studied the effects of a laser beam on Aβ fibrils. As was the case for K3 fibrils, extensive irradiation destroyed the preformed Aβ fibrils. However, irradiation during spontaneous fibril formation resulted in only the partial destruction of growing fibrils and a subsequent explosive propagation of fibrils. The explosive propagation was caused by an increase in the number of active ends due to breakage. The results not only reveal a case of fragmentation-induced propagation of fibrils but also provide insights into therapeutic strategies for AD.     

Plasmodium falciparum: Attenuation by irradiation

The effect of irradiation on the in vitro growth of Plasmodium falciparum was investigated. The cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. The stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. The greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont stages to young ring forms. The characteristics of radiosensitive variation in the parasite cycle resembled that of mammalian cells. Growth curves of parasites exposed to doses of irradiation upto 150 gray had the same slope as nonirradiated controls but parasites which were exposed to 200 gray exhibited a growth curve which was less steep than that for parasites in other groups. Less than 10 organisms survived from the 10⁶ parasites exposed to this high dose of irradiation; the possibility exists of obtaining radiation-attenuated P. falciparum.     

Impact of Pulsed Nd:YAG Laser Irradiation on the Growth and Mortality of the Biofilm Forming Marine Bacterium Pseudoalteromonas carrageenovora

The impact of pulsed laser irradiation on the marine biofilm forming bacterium Pseudoalteromonas carrageenovora was investigated in the laboratory by monitoring mortality and the post-irradiation growth pattern. The impact of laser irradiation on bacterial mortality increased with the duration of irradiation. Laser irradiation at 532 nm (0.1 J cm m 2 ) for 15 min resulted in a 53% cell mortality immediately after irradiation. However, the impact after a period of 5 h (delayed impact) was more severe. The growth pattern of irradiated samples showed a prolonged lag phase compared to the reference, due to a reduction in total viable counts (TVC) in the irradiated samples. Nucleic acid staining is suggested to be a promising technique for monitoring laser inflicted bacterial mortality. Thus, the results suggest that laser irradiation could be considered as an alternative technique to reduce the number of biofilm forming bacteria and thereby biofilm formation on hard surfaces.