Anionic polymerization of exo-3,4,5-trithiatetracyclo[5.5.1.O2,6.O8,12]tridec-10-ene (dicyclopentadiene trisulfide)

The anionic polymerization of exo-3,4,5-trithiatetracyclo[5.5.1.O^2,6.O^8,12]tridec-10-ene ( 1 ) in bulk and/or in aromatic solvents (benzene, toluene) was studied. The polymerization was initiated with sodium benzenethiolate (sodium cation complexed with dibenzo-18-crown-6). Polymers with high-molecular weights were obtained (M _n ≈ 10⁵, osmometrically). The polymerization was found to be living and reversible; the equilibrium monomer concentration increases with the temperature. The ceilling temperature was estimated as 167°C. The thermodynamic data of the polymerization in toluene was determined and compared with those of the polymerization of exo-3,4,5-trithiatricyclo[5.2.O^2,6]decane. The standard enthalpy ΔH = ?(6,6 ± 0,6)kJ · mol ¹ and entropy ΔS = ?(29,3 ± 2,1)J · mol ¹ · K ¹ of the polymerization of 1 were evaluated from the temperature dependence of the equilibrium monomer concentration, determined dilatometrically.     

Evaluation of tracheal stenosis: comparison between computed tomography virtual tracheobronchoscopy with multiplanar reformatting,flexible tracheofiberoscopy and intra-operative findings

The aim of the study was to evaluate and compare various helical CT display modes [virtual endoscopy (VE)] and multiplanar reformations (MPR), conventional flexible tracheobronchoscopy (FT) and intra-operative (IO) findings in patients with tracheal stenosis and to analyze the advantage of MPR and VE in diagnosis and treatment planning and in postoperative follow-up. Thirty-seven patients with tracheal stenosis underwent standard neck and chest CT followed by MPR and VE. Results were correlated with the results of FT and IO findings. Thirty-three of the 37 stenoses were correctly graded and measured adequately using VE. Complete correlation among CT, fiberoptic tracheoscopy, and surgery of stenosis grading, stenosis length and length of planned resection segment of the trachea was noted between 33 of 37 patients with tracheal stenosis. Correlation between VE and IO was noted in 35 of 37 patients and between FT and VE was noted in 33 of 37 patients with tracheal stenosis. The sensitivity of VE was 94–97%, specificity was 100% with comparison to IO findings. The sensitivity and accuracy of MPR was 86–89% and specificity was 100% with comparison to FT findings. The results of the study indicate that VE is an excellent, consistent, and objective technique. VE with MPR is very useful in diagnostic evaluation and treatment planning in patients with tracheal stenosis.     

Association of Trp64Arg polymorphism of beta3-adrenergic receptor with insulin resistance in Polish children with obesity

AIM: To establish the influence of the Trp64Arg variant of the beta3-adrenergic receptor (Trp64Arg- beta3AR) on body mass index (BMI) and insulin resistance (IR) in obese children. METHODS: BMI, presence of the Trp64Arg mutation, plasma glucose and insulin concentrations during an oral glucose tolerance test (OGTT) and IR were determined in 60 obese and 33 normal weight children. RESULTS: The frequency of Trp64Arg was similar in normal weight and obese children. BMI, glucose and insulin concentrations during an OGTT in children with Trp64Argbeta3AR were not different from those with Trp64Trpbeta3AR. IR was confirmed in 42.8% of children with Trp64Argbeta3AR and in 45.6% of children with Trp64Trpbeta3AR (NS). CONCLUSIONS: 1. The similar frequency of the Trp64Argbeta3AR variant in normal weight and obese children suggests that it is not a susceptibility gene for obesity in Polish children. 2. The presence of the Trp64Argbeta3AR variant does not have an unfavourable influence on BMI, glucose or insulin concentrations during OGTT or on IR frequency in Polish obese children.     

Pseudomonas aeruginosa biofilm is a potent inducer of phagocyte hyperinflammation

Objective

Pseudomonas aeruginosa effectively facilitate resistance to phagocyte killing by biofilm formation. However, the cross talk between biofilm components and phagocytes is still unclear. We hypothesize that a biofilm provides a concentrated extracellular source of LPS, DNA and exopolysaccharides (EPS), which polarize neighbouring phagocytes into an adverse hyperinflammatory state of activation.

Methods

We measured the release of a panel of mediators produced in vitro by murine neutrophils and macrophages exposed to various biofilm components of P. aeruginosa cultures.

Results

We found that conditioned media from a high biofilm-producing strain of P. aeruginosa, PAR5, accumulated high concentrations of extracellular bacterial LPS, DNA and EPS by 72 h. These conditioned media induced phagocytes to release a hyperinflammatory pattern of mediators, with enhanced levels of TNF-α, IL-6, IL12p40, PGE₂ and NO. Moreover, the phagocytes also upregulated COX-2 and iNOS with no influence on the expression of arginase-1.

Conclusions

Phagocytes exposed to biofilm microenvironment, called by us biofilm-associated neutrophils/macrophages (BANs/BAMs), display secretory properties similar to that of N1/M1-type phagocytes. These results suggest that in vivo high concentrations of LPS and DNA, trapped in biofilm by EPS, might convert infiltrating phagocytes into cells responsible for tissue injury without direct contact with bacteria and phagocytosis.

     

Using qualitative methods to inform the design of a decision aid for people with advanced cystic fibrosis: The InformedChoices CF patient decision aid

ObjectiveTo assess information needs of adults with Cystic Fibrosis and their families toward designing a patient decision aid about invasive mechanical ventilation (IMV) and lung transplant.MethodsFocus groups and in-depth interviews explored participants’ knowledge, prior clinical conversations, and decisions about IMV and lung transplant. Interviews and focus groups were recorded and transcribed for analysis.ResultsN = 24 participants were recruited. Themes identified were: prior communication with clinicians, decision-making process, and living with CF. Participants having prior conversations with CF clinicians regarding: lung transplant (N = 17/74%), and IMV (N = 3/13%). Most 15(65%) felt it was important to hear patients’ real-life experience, others (3/13%) relied on their CF doctors for information. Most people (16/70%) believed hearing prognosis was helpful, but 5(22%) found this information frightening. High degrees of social isolation and a desire for more interaction with other CF adults were found.ConclusionsQualitative methods helped identify areas important for decision making about IMV and LT for CF adults. Future directions include usability and feasibility testing of the decision aid.Practice implicationsBecause IMV is rarely discussed with CF adults, clinicians might approach this topic, as with transplant, as lung function begins to decline. CF-care teams should also foster CF patient-level information exchange.     

Increase of interleukin 6 and decrease of interleukin 2 production during the ageing process are influenced by the health status

The ageing process is accompanied by the disregulation of interleukin 2 (IL2) and interleukin 6 (IL6) production. In our paper, we asked whether the age between 60 and 70 years is a turning point for the disregulation of both IL2 and IL6 production. Fifty volunteers 60–70 years old, 25 aged 36–59, and 50 of 20–35 years old were enrolled into the study. Their health status was graded according to the criteria of the Senieur Protocol (SP) as ‘healthy' and ‘almost-healthy'. The cytokines level was determined in the sera of the volunteers. Moreover, the spontaneous release of IL6 by peripheral blood mononuclear cells (PBMC) and the activity of the IL6 gene in non-stimulated PBMC were also analysed. Cytokine levels were measured by biological assays, mRNA for IL6 was detected by RT-PCR method. The results showed that the production of IL2 is not disregulated in the ‘healthy' people until the age of 60–70. People not fulfilling all SP criteria are characterised by a lower level of IL2 in the sera. The overproduction of IL6 into the sera and supernatants from non-stimulated PBMC and PBL as well as the activation of IL6 gene start between the ages 36 and 59 and is more pronounced in the ‘almost-healthy'.     

Factors regulating the influence of melatonin on hippocampal evoked potentials: comparative studies on different strains of mice

Sexual dimorphisms are present throughout the zebra finch song system, from forebrain centers to the tracheosyringeal portion of the hypoglossal nucleus (nXIIts) to the muscles of the syrinx (vocal organ). In females, gonadal steroids administered during development can partially masculinize the telencephalic areas, and in adulthood can increase the size of syrinx muscles. In the present study, two experiments were designed to investigate the role of early androgen and estrogen in the development of nXIIts and the ventralis and dorsalis muscles of the syrinx. In experiment one, males and females were treated with testosterone, estradiol, dihydrotestosterone, the anti-androgen flutamide, or a vehicle control for 21 days after hatching. At day 60, nXIIts volume, motoneuron soma size and number were assessed, as well as syrinx weight and the size of ventralis and dorsalis fibers. In experiment two, animals were administered either the estrogen synthesis inhibitor, fadrozole, or vehicle, and the syrinx measurements were taken at day 60. Male-biased sex differences were detected on all measures in both experiments, and several right-side biases were detected. In females, dihydrotestosterone masculinized soma size in nXIIts and testosterone slightly increased syrinx weight. E2 feminized the syrinx of males. However, flutamide did not prevent masculine development of either structure, and fadrozole did not inhibit feminine syrinx development. These results are consistent with the idea that, as in the forebrain, steroid hormones can stimulate aspects of sexual differentiation, but they may not be direct triggers for the process.     

Pathogenesis and management of Grave's ophthalmopathy

The most recent hypothesis on pathogenesis of Graves' Ophthalmopathy (GO) and short characteristics of the disease was presented. Emphasis was placed on the necessity of coordinated treatment of the thyroid dysfunction and ophthalmopathy. Management of hyperthyroidism and Graves' ophthalmopathy, including the latest methods was described.     

Comparison of tissue distribution and metabolism of 1,2- and 1,4-dibromobenzenes in female rats

The distribution, excretion and metabolism of 1,4-dibromobenzene (1,4-DBB) and 1,2-dibromobenzene (1,2-DBB), following a single intraperitoneal administration to female Wistar rats, were investigated using radiotracer 3H and GC-MS technique. The maximum level of 3H after 1,4-DBB administration was detected in all examined rat tissues between 4 and 24 h foltowing the injection. The highest concentrations of 3H were found in fat tissue, muscles, adrenal glands and sciatic nerve. About 50% of administered dose was still retained in the rat 72 h after injection. For 1,2-DBB, the highest level of 3H was in the liver, kidneys and fat tissue 4 and 8 h after administration. Three days after injection, less than 2% of the given dose was retained in the rat body. Urine turned out to be the main route of 3H excretion following the injection of both compounds (30% and 82%, after 1,4-DBB and 1,2-DBB, respectively), and about 4% of the given dose was excreted in feces. In urine of rats the following substances were identified (in sequence 1,4-dBB and 1,2-dBB): (1) unchanged parent compounds (5 and 11%); (2) dibromophenols (84 and 73%); (3) dibromothiophenols (5 and 10%) and (4) monobromophenols (1.9 and 0.7%). This study suggests that 1,2-DBB is characterized by a relatively high turnover rate, whereas 1,4-DBB shows a tendency for long-term retention in the body.     

Biopharmaceutical assessment of eye drops containing aloe (Aloe arborescens Mill.) and neomycin sulphate

The subject of the studies was eye drops made of aloe, containing the group of aloe chemical substances of anti-inflammatory use and neomycin sulphate. The aim of the studies was to evaluate the permeability of biologically active aloe substances, determined as aloenin, through synthetic lipophilic and hydrophilic membranes in a standard perfusion apparatus and in vitro verification of the transport possibilities of these substances through the isolated cornea of pig's eye. The permeability process of biologically active aloe substances determined as aloenin, through synthetic lipophilic and hydrophilic membranes, was analyzed using the first-order kinetics. Estimated quotas of permeability rate constant show that the investigated chemical compounds of aloe, included in the eye drops, diffused through the applied membranes. The studies of permeability through isolated pig's cornea proved that biologically active aloe substances could not overcome this biological barrier. On the basis of biopharmaceutical studies it can be concluded that the eye drops containing aloe and neomycin sulphate, due to the lack of permeating abilities through the eye cornea, should be particularly useful in the treatment of inflammations and infections of external parts of the eye, such as conjuctiva, eyelid edges, lacrimal sac and cornea.