A gallium complex with a new tripodal tris-hydroxypyridinone for potential nuclear diagnostic imaging: solution and in vivo studies of 67Ga-labeled species

The gallium(III) complex of a new tripodal 3-hydroxy-4-pyridinone (3,4-HP) chelator has been studied in terms of its physico-chemical and in vivo properties aimed at potential application as probe for nuclear imaging. In particular, based on spectrophotometric titrations, the hexa-coordinated (1:1) gallium complex appeared as the major species in a wide physiological acid-neutral pH range and its high stability (pGa = 27.5) should avoid drug-induced toxicity resulting from Ga(III) accumulation in tissues due to processes of transmetallation with endogenenous ligands or demetallation. A multinuclear (¹H and ⁷¹Ga) NMR study gave some insights into the structure and dynamics of the gallium(III) chelate in solution, which are consistent with the tris-(3,4-HP) coordination and an eventual pseudo-octahedral geometry. Biodistribution and scintigraphic studies of the ⁶⁷Ga(III) labelled chelate, performed in Wistar rats, confirmed the in vivo stability of the radiolabelled complex, its non interaction with blood proteins and its quick renal clearance. These results indicate good perspectives for potential application of extrafunctionalized analogues in radiodiagnostic techniques.     

Combined chelation of bi-functional bis-hydroxypiridinone and mono-hydroxypiridinone: Synthesis, solution and in vivo evaluation

3-Hydroxy-4-pyridinones (3,4-HP) are well known iron-chelators with applications in medicinal chemistry, mainly associated with their high affinity towards trivalent hard metal ions (e.g. M³⁺, M = Fe, Al, Ga) and use as decorporating agents in situations of metal accumulation. The polydenticity and the extra-functionality of 3,4-HP derivatives have been explored, aimed at improving the chelating efficacy and the selectivity of the interaction with specific biological receptors. However, the ideal conjugation of both features in one molecular unity usually leads to high molecular weight compounds which can have crossing-membrane limitations.Herein, a different approach is used combining a arylpiperazine-containing bis-hydroxypyridone (H₂L¹) with a biomimetic mono-hydroxypyridinone, ornithine-derivative (HL²), to assess the potential coadjuvating effect that could result from the administration of both compounds for the decorporation of hard metal ions. This work reports the results of solution and in vivo studies on their chelating efficacy either as a simple binary or a ternary system (H₂L¹:HL²:M³⁺), using potentiometric and spectrophotometric methods. The solution complexation studies with Fe(III) indicate that the solubility of the complexes is considerably increased in the ternary system, an important feature for the metal complex excretion, upon the metal sequestration. The results of the in vivo studies with ⁶⁷Ga-injected mice show differences on the biodistribution profiles of the radiotracer, upon the administration of each chelating agent, that are mainly ascribed to the differences of their extra-functional groups and lipo/hydrophilic character. However, administration of both chelating agents leads to a more steady metal mobilization, which may be attributed to an improved access to different cellular compartments.     

Design and development of a proniosomal transdermal drug delivery system of caffeine for management of migraine: In vitro characterization, 131I-radiolabeling and in vivo biodistribution studies

Caffeine is a naturally occurring alkaloid compound which is widely used alone or in combination in the treatment of migraine. The short elimination half life of caffeine (3−5 h) and the relationship between its absorption from gastrointestinal tract and gastric emptying are the major obstacles toward its effective oral delivery. To surmount such limitations, transdermal proniosomal systems of caffeine were developed. A full 3² factorial design was employed using Design-Expert® software to study the effect of different parameters and to select the optimal proniosomal system (PNS-4). Skin irritation study and in vivo histopathological examination confirmed the safety of transdermal application of PNS-4. Radioiodination of caffeine using iodine-131 (¹³¹I) was performed via direct electrophilic substitution reaction. Insilco docking results showed almost the same binding affinity of caffeine and ¹³¹I-Caffeine against adenosine A_2A receptor. Biodistribution results showed that, transdermal ¹³¹I-Caffeine loaded PNS-4 (patch) significantly increased the residence of ¹³¹I-Caffeine in the blood with higher brain targeting than oral suspension. The obtained results proved that, PNS-4 represents a promising transdermal drug delivery system capable of overcoming challenges facing oral delivery of caffeine.     

Gallium-67 as a Potential Marker for Aluminium Transport in Rat Brain: Implications for Alzheimer''s Disease

Evidence of a link between aluminium and Alzheimer's disease, parkinsonism-dementia of Guam, and dialysis encephalopathy raises questions regarding the role of this element in the pathogenesis of these conditions. Therefore, we have investigated the use of gallium-67 (67Ga) as a marker for brain uptake of aluminium. The binding of 67Ga to plasma proteins has been studied, and the blood-brain barrier permeability and autoradiographic distribution of this isotope in rat brain determined in vivo. The autoradiographic distribution of 125I-Fe-transferrin receptors in rat brain has also been determined in vitro. Results show that 67Ga was bound to plasma transferrin, entered the brain with a blood-brain barrier permeability of 2.48 x 10(-6) ml/min/g, and showed a marked regional distribution that was very similar to that of 125I-Fe-transferrin receptors. Our data suggest that the vulnerability of the hippocampus, amygdala, and cerebral cortex in conditions such as those mentioned above may be partly due to an increased uptake and deposition of aluminium in these regions by the iron transport system.     

Rate of biodistribution of STEALTH® liposomes to tumor and skin: influence of liposome diameter and implications for toxicity and therapeutic activity

The influence of diameter on the pharmacokinetic and biodistribution of STEALTH® liposomes into the tumor (4T1 murine mammary carcinoma) and cutaneous tissues (skin and paws) of mice was studied to ascertain the time course of liposome accumulation and to determine if a preferential accumulation of liposomes into tumor over skin or paws could be achieved by altering liposome size. These tissues were chosen as the dose-limiting toxicity for Caelyx™/Doxil® in humans is palmar-plantar erythrodysesthesia, a cutaneous toxicity. We examined liposomes of four diameters: 82, 101, 154, or 241 nm. Liposomes with the three smallest diameters showed similar accumulation profiles that were significantly higher than the largest liposomes in all three tissues of interest. We were unable to achieve a preferential accumulation of liposomes into tumor over skin or paws based on size alone, as evidenced by the tumor to skin and tumor to paw ratios. However, there were differences in the time courses of liposome accumulation in these three tissues. Liposome levels plateaued in tumors and paws within 24 h, whereas skin levels plateaued between 24 and 48 h. The therapeutic activity of liposomal doxorubicin of three diameters (100, 157, and 255 nm) was tested in the same model. All formulations delayed tumor growth, with liposomes of 100 or 157 nm being equally efficacious and superior to liposomes of 255 nm.     

Novel thiobarbiturates as potent urease inhibitors with potential antibacterial activity: Design,synthesis, radiolabeling and biodistribution study

Urease enzyme is a virulence factor that helps in colonization and maintenance of highly pathogenic bacteria in human. Hence, the inhibition of urease enzymes is well-established to be a promising approach for preventing deleterious effects of ureolytic bacterial infections. In this work, novel thiobarbiturate derivatives were synthesized and evaluated for their urease inhibitory activity. All tested compounds effectively inhibited the activity of urease enzyme. Compounds 1, 2a, 2b, 4 and 9 displayed remarkable anti-urease activity (IC₅₀ = 8.21–16.95 μM) superior to that of thiourea reference standard (IC₅₀ = 20.04 μM). Moreover, compounds 3a, 3g, 5 and 8 were equipotent to thiourea. Among the tested compounds, morpholine derivative 4 (IC₅₀ = 8.21 µM) was the most potent one, showing 2.5 folds the activity of thiourea. In addition, the antibacterial activity of the synthesized compounds was estimated against both standard strains and clinical isolates of urease producing bacteria. Compound 4 explored the highest potency exceeding that of cephalexin reference drug. Moreover, biodistribution study using radiolabeling approach revealed a remarked uptake of ^99mTc-compound 4 into infection induced in mice. Furthermore, a molecular docking analysis revealed proper orientation of title compounds into the urease active site rationalizing their potent anti-urease activity.     

Heterocyclic zinc-binding groups for use in next-generation matrix metalloproteinase inhibitors: potency, toxicity, and reactivity

In an effort to improve the zinc-chelating portion of matrix metalloproteinase (MMP) inhibitors, we have developed a family of heterocyclic zinc-binding groups (ZBGs) as alternatives to the widely used hydroxamic acid moiety. Elaborating on findings from an earlier report, we performed in vitro inhibition assays with recombinant MMP-1, MMP-2, and in a cell culture assay using neonatal rat cardiac fibroblast cells. In both recombinant and cell culture assays, the new ZBGs were found to be effective inhibitors, typically 10–100-fold more potent than acetohydroxamic acid. The toxicity of these chelators was examined by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt cytotoxicity assays, which demonstrate that most of these compounds are nontoxic at concentrations of almost 100 μM. To address the possible interaction of sulfur-containing ZBGs with biological reductants, the reactivity of these chelators with 5,5′-dithiobis(2-nitrobenzoic acid) was examined. Finally, thione ZBGs were shown to be effective inhibitors of cell invasion through an extracellular matrix membrane. The data presented herein suggest these heterocyclic ZBGs are potent, nontoxic, and biocompatible compounds that show promise for incorporation into a new family of MMP inhibitors.     

乙型肝炎疫苗与卡介苗、百白破混合菌苗的联合免疫效果观察

本文报道150名HBsAg阴性产妇所生新生儿在实施计划免疫的同时,1、2组分别接种10μg、20μg乙肝疫苗,3组不接种乙肝疫苗,以了解乙肝疫苗与卡介苗、百白破联合免疫的免疫应答。结果表明:1.2组抗-HBc达到有效保护的(P/N≥5)为93.18％和89.58％,无显著差异;两组均未检出HBV标志物,但是未注射乙肝疫苗组HBV感染达6.67％。乙肝疫苗与卡介苗、百白破联合免疫应答是好的,抗原间无干扰,从而证明乙肝疫苗不但能有效地控制乙型肝炎,并能纳入扩大免疫规划。     

丙泊酚复合麻醉在实验犬外科手术中的效果观察

目的丙泊酚复合麻醉应用于实验犬外科手术,进行效果评价。方法成年健康杂种犬13只,雌雄不限。术前30 min肌内注射阿托品0.5 mg,吗啡10 mg,进行气管插管,静脉注射氯胺酮50 mg,静脉注射丙泊酚首次剂量5 mg/kg体重,维持剂量1 mg/kg。结果丙泊酚复合麻醉,平均麻醉起效时间40 s,首次剂量平均维持17.3min,重复给药平均维持13.6 min,无死亡。丙泊酚有较强的麻醉效果,诱导时间短,起效快,恢复快速平稳,而且无副作用。结论丙泊酚复合麻醉适合于犬的外科手术实验,是一种较为理想的麻醉方法。     

Combined administration of N-acetylcysteine and monoisoamyl DMSA on tissue oxidative stress during arsenic chelation therapy

The present study deals with the therapeutic potential of combined administration of N-acetylcysteine (NAC) along with monoisoamyl DMSA (MiADMSA) against chronic arsenic poisoning in guinea pigs. Animal were exposed to 50 ppm arsenic in drinking water for 8 mo and subsequently treated for 5 consecutive days with 100 mg/kg NAC (orally) and MiADMSA (intraperitoneally), individually or in combination (50 mg/kg each). Arsenic exposure produced a significant depletion of blood δ-aminolevulinic acid dehydrate (ALAD) activity, increased the blood zinc protoporphyrin (ZPP) level, and reduced blood and liver glutathione (GSH) levels in guinea pigs. Hepatic oxidized glutathione (GSSG) and thiobarbituric acid reactive substance (TBARS) levels showed a marked increase, whereas hepatic alkaline phosphatase (ALP) activity decreased and acid phosphatase (ACP) activity increased on arsenic exposure. Significant depletion of liver transaminase activities on arsenic exposure suggests organ injury. Administration of MiADMSA, alone and in combination with NAC after arsenic exposure, was able to significantly enhance hepatic GSH and to reduce GSSG and TBARS levels compared to the arsenic control. Biochemical variables indicative of liver injury generally remained insensitive to any of these treatments. The recoveries in parameters indicative of oxidative stress were more marked in guinea pigs treated with combined administration of NAC and MiADMSA than monotherapy. Interestingly, there was a more pronounced depletion of arsenic from blood and tissues after combined treatment with NAC plus MiADMSA than MiADMSA. Blood and tissues copper, zinc, iron, and calcium concentrations showed a significant increase after arsenic exposure, which showed improvement, particularly after combined administration of MiADMSA and NAC. Based on these data, a proposal can be made that greater effectiveness in chelation treatment against chronic arsenic poisoning (i.e., turnover in the oxidative stress and removed of arsenic from the system) could be achieved by combined administration of an antioxidant (preferably having a thiol moiety) with MiADMSA.     

Zn-polyphenol chelation: complexes with quercetin, (+)-catechin, and derivatives: II Electrochemical and EPR studies

In this work, we have studied the formation of complexes between flavonols, (quercetin, rutin, quercitrin, kaempferol, luteolin, tamarixetin) and flavanols ((+)-catechin, (−)-epicatechin), flavanonol, (+)-taxifolin, and Zn acetate in two hydro-organic media at neutral pH in the absence of oxygen. The complexation was first studied by cyclic voltammetry. Then preparative electrolysis have been attempted followed by coulometry, UV-Vis optical absorption and circular dicroism spectroscopies for characterizing the oxidized compounds. Spectroelectrochemistries monitored either in the UV-Vis or in the EPR spectrometers at room temperature have been also used and we have identified o-semi-quinone intermediates in some cases. Different behaviour vis-à-vis the complexation by Zn²⁺ according to the molecular structures of these different families of polyphenols have been found. Some of them are more easily oxidizible.     

Fluorescent sensors based on BODIPY derivatives for aluminium ion recognition: an experimental and theoretical study

Two BODIPY derivative sensors for metal ion recognition containing 10-(4-hydroxyphenyl) (L1) and 10-(3,4-dihydroxyphenyl) (L2) were synthesized in a one-pot reaction of benzaldehyde derivative and 2,4-dimethylpyrrole in the presence of trifluoroacetic acid as catalyst. The binding abilities between these sensors and 50 equivalents of Na⁺, K⁺, Ag⁺, Ca²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺, Pb²⁺, Al³⁺ and Cr³⁺ ions were studied using UV–vis and fluorescent spectroscopic methods. Of all the metal ions tested, Al³⁺ ion showed the greatest decrease in intensity in the spectra of the sensors, and therefore Al³⁺ ion forms the strongest complex. The binding abilities of BODIPY receptors with Na⁺, Ag⁺, Ca²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺ and Al³⁺ ions were also investigated using density functional theory (DFT) calculations at B3LYP/LanL2DZ theoretical level. The calculated results point to the same conclusion. DFT calculations also provided the HOMO–LUMO energy levels, which can explain the spectrum change upon complexation.

Zn-polyphenol chelation: complexes with quercetin, (+)-catechin, and derivatives: I optical and NMR studies

The complexation of Zn²⁺ by quercetin, (+)-catechin and several derivatives has been investigated in the aim to determine the stoichiometry and the stereospecificity and its influence on their antioxidant properties. These studies have been conducted under anaerobic conditions in hydro-organic solvents buffered at pH 7 using UV-Vis and ¹H NMR spectroscopies. From the evolution of the spectra of the flavonoids with the concentration of ZnAc their stoichiometry and the coordination sites were determined.     

A- NK 细胞联合IL- 2, IL- 12 在肿瘤免疫治疗中的作用

本文对A-NK细胞联合IL-2和IL-12在抗肿瘤免疫治疗中的作用进行了论述。强调联合应用可高效激活A-NK细胞,提高对肿瘤细胞的杀伤活性。减少IL-2和IL-12的用量及副作用,提高疗效。     

The possible protective and therapeutic effects of ginger and cinnamon on the testis and coda epididymis of streptozotocin-induced-diabetic rats: Histological and biochemical studies

Diabetes mellitus (DM) is a metabolic condition characterized by high blood sugar levels with serious system complications. Ginger (Zingiber officinale) and Cinnamon (Cinnamomum zeylanicum) have anti-diabetic activities. The goal of this study is to evaluate the possible protective and therapeutic effects of ginger and Cinnamon against histological, Ki67 Immunohistochemistry (IHC) and biochemical studies in testis and coda epididymis of Streptozotocin (STZ) induced diabetic rats. The experimental rats were divided into six groups: G1 was the control, G2 induced diabetic without treatment, G3 was treated with ginger before induction of DM (ginger protective), G4 were given ginger after DM induction (ginger therapeutic), G5 were given cinnamon before induction of DM (cinnamon protective) and G6 were given cinnamon after DM induction (cinnamon therapeutic). In diabetic rats’ significant increases in fasting blood sugar and body weight were observed after three weeks. Ginger and cinnamon effectively decreased serum glucose levels. Histopathological evaluations of seminiferous tubules and coda epididymis sections from diabetic rats showed severe damage to them. Furthermore, the sections of seminiferous tubules and coda epididymis rats administered ginger and cinnamon extract showed normal structure, healthy lining epithelium and sperm contents compared to diabetic rats. The results of the study show that both Ginger and Cinnamon aqueous extracts are effective as both hypoglycemic natural supplements that can protect against diabetic-induced testicular damage as well as share in the reservation of the cauda epididymal structure and sperm contents.     

Combined effects of formalin fixation and tissue processing on immunorecognition

Abstract

It is accepted that aldehyde-based fixation of cells can affect immunodetection of antigens; however, the effects of tissue processing on immunodetection have not been analyzed systematically. We investigated the effects of aldehyde-based fixation and the various cumulative steps of tissue processing on immunohistochemical detection of specific antigens. DU145 (prostate) and SKOV3 (ovarian) cancer cell lines were cultured as monolayers on microscope slides. Immunohistochemical detection of Ki67/MIB-1 and proliferating cell nuclear antigen (PCNA) was evaluated after various fixation times in 10% neutral buffered formalin and after each of the several cumulative steps of tissue processing. The effect of antigen retrieval (AR) was evaluated concomitantly as an additional variable. Our results indicate that in addition to fixation, each of the tissue processing steps has effects on immunorecognition of the epitopes recognized by these antibodies. Extensive dehydration through ethanols to absolute ethanol had only modest effects, except for the detection of Ki67/MIB-1 in SKOV-3 cells where the effect was stronger. In general, however, establishment of a hydrophobic environment by xylene resulted in the greatest decrease in immunorecognition. AR compensated for most, but not all, of the losses in staining following fixation and exposure to xylene; however, AR gave consistent results for most steps of tissue processing, which suggests that AR also should be used for staining PCNA. The cellular variations that were observed indicate that the effects of fixation and other steps of tissue processing may depend on how antigens are packaged by specific cells.     

地塞米松对腰硬联合麻醉剖宫产术后腰背痛及神经并发症影响

目的：硬膜外腔注射地塞米松对腰硬联合麻醉腰背痛及神经并发症的预防效果。方法：将200例ASA I-II腰联合麻醉下择期剖宫产患者随机分成2组,A组吗啡2 mg＋生理盐水稀释至10ml硬膜外腔注射;B组向硬膜外腔注射吗啡2mg＋地塞米松5mg＋生理盐水稀释至10 ml硬膜外腔注射。术毕两组均行静脉术后镇痛。观察并记录患者术后24,72 h的腰背痛及神经并发症情况,同时记录每例患者试穿次数。结果：B组患者术后24,72 h的背痛发生率为11.0%,4.0%,明显低于A组（P〈0.05）;穿刺1次和2次及以上背痛的发生率分别为5.1%和19.5%,明显低于A组（P〈0.05）。两组72h内神经并发症差异无统计学意义。结论：硬膜外腔注射地塞米松有效预防腰硬联合麻醉剖宫产术后腰背痛,但对神经并发症的影响还有待进一步观察。     

血浆HSP60 和TSGF联合检测甲状腺癌的早期诊断价值

目的:究血浆热休克蛋白-60(HSP60)与肿瘤特异性生长因子(TSGF)联合检测对甲状腺癌的早期诊断价值。方法:于2011年1月~2015年11月期间选取254例甲状腺癌患者(定为甲状腺癌组)、156例结节性甲状腺肿患者(结节性甲状腺肿组)和202例健康者(健康组)为研究对象,采用ELISA法检测三组血浆HSP60、TSGF水平,分析其与甲状腺癌病理因素的关系及诊断的敏感度和特异度。结果:甲状腺癌组的血浆HSP60、TSGF水平均显著高于结节性甲状腺肿组以及健康组,且结节性甲状腺肿组高于健康组,差异均具有统计学意义(P0.05)。甲状腺癌患者血浆HSP60、TSGF水平与年龄、性别、临床分期均无相关性(P0.05)。血浆HSP60、TSGF单独诊断甲状腺癌的敏感度和特异度分别为68.75%、81.82%和83.33%、71.88%,两者联合诊断的敏感度和特异度则分别达到了88.89%和86.72%。结论:在甲状腺癌的早期诊断中,采用血浆HSP60和TSGF联合检测的方式可靠性较高,值得推广应用。     

Combined effect of salinity and excess boron on plant growth and yield

Plants are likely to be affected by simultaneous salinity and boron (B) toxicity stresses due to exposure to soils with high levels of naturally occurring salinity and B, or due to irrigation with water containing high levels of salts, including B. Inadequate information regarding the response of plants to the combination of excess B and salinity on plant growth and yield is available, and there is no consensus concerning mutual relations between salinity stress and B toxicity. Growth and yield of bell pepper (Capsicum annuum L.) were measured at different B and salinity levels in two greenhouse experiments. The results from these experiments and from published data for wheat, tomato and chickpea were analyzed according to the Abbott method to define the combined effect of B and salinity on plant growth and yield. Application of the Abbott method for the experiments on peppers generally implied an antagonistic relationship for excess B and salinity. In other words, toxic effects on growth and yield were less severe for combined B toxicity and salinity than what would be expected if effects of the individual factors were additive. Similar antagonistic characteristics were found using data from three of the five studies reported in the literature. The mechanism of relationships between B and salinity in plants is not clear and several options are discussed. Prominent among the possible explanations are reduced uptake of B in the presence of Cl and reduced uptake of Cl in the presence of B.     

The Comparative and Combined Inhibitory Effects of MTBE and TBA on the Activities of Soil Exoenzymes

Methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) are major soil contaminants, and they have been actively investigated for their toxic effects on living organisms in soil ecosystems. Although previous studies have been used as tools to evaluate the health of soil, they have been limited in scope and ability to analyze the overall microbial activity. In the present study, the effects of MTBE and TBA on the activity of soil exoenzymes including urease, acid phosphatase, arylsulfatase, β-glucosidase, dehydrogenase, and fluorescein diacetate hydrolase, which are involved in nutrient cycles and overall microbial activities, were investigated. Soil samples were treated with 0–2% of MTBE and TBA solutions, and the comparative effects and combined effects on quantity of active soil exoenzymes were determined. The activity of six exoenzymes exposed solely to MTBE and TBA did not significantly change with dose concentration or exposure time, but did show significant changes when exposed to high concentrations of MTBE and TBA combined, with dehydrogenase being the most affected. Therefore, we proposed dehydrogenase as a potential biomarker to assess the risk of co-contamination of MTBE and TBA.