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1.
J Periodontal Res ; 48(1): 1-21, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22582923

ABSTRACT

Periodontitis is accompanied by the proliferation of small blood vessels in the gingival lamina propria. Specialized postcapillary venules, termed periodontal high endothelial-like venules, are also present, and demonstrate morphological and functional traits similar to those of high endothelial venules (HEVs) in lymphatic organs. The suggested role of HEVs in the pathogenesis of chronic periodontitis involves participation in leukocyte transendothelial migration and therefore proinflammatory effects appear. Recent observations suggest that chronic periodontitis is an independent risk factor for systemic vascular disease and may result in stimulation of the synthesis of acute phase protein by cytokines released by periodontal high endothelial cells (HECs). However, tissue expression of HEV-linked adhesion molecules has not been evaluated in the gingiva of patients with chronic periodontitis. This is significant in relation to potential therapy targeting expression of the adhesion molecules. In this review, current knowledge of HEV structure and the related expression of four surface adhesion molecules of HECs [CD34, platelet endothelial cell adhesion molecule 1, endoglin and intercellular adhesion molecule 1 (ICAM-1)], involved in the key steps of the adhesion cascade in periodontal diseases, are discussed. Most studies on the expression of adhesion molecules in the development and progression of periodontal diseases pertain to ICAM-1 (CD54). Studies by the authors demonstrated quantitatively similar expression of three of four selected surface markers in gingival HEVs of patients with chronic periodontitis and in HEVs of reactive lymph nodes, confirming morphological and functional similarity of HEVs in pathologically altered tissues with those in lymphoid tissues.


Subject(s)
Cell Adhesion Molecules/physiology , Chronic Periodontitis/pathology , Venules/physiology , Capillaries/physiology , Endothelial Cells/pathology , Endothelium, Lymphatic/pathology , Endothelium, Vascular/pathology , Gingiva/blood supply , Humans , Transendothelial and Transepithelial Migration/physiology
2.
Magn Reson Chem ; 50(2): 89-105, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22354770

ABSTRACT

Two antibacterial and antifungal agents, chloroxylenol (4-chloro-3,5-dimethyl-phenol) and triclosan (5-chloro-2-(2',4'-dichlorophenoxy)-phenol), were studied experimentally in solid state with an X-ray, (35)Cl-nuclear quadrupole resonance (NQR) and (17)O-nuclear quadrupole double resonance (NQDR) spectroscopies and, theoretically, with the density functional theory/quantum theory of atoms in molecules (DFT/QTAIM). The crystallographic structure of triclosan, which crystallises in space group P31 with one molecule in the asymmetric unit [a = 12.64100(10), b = 12.64100(10), c = 6.71630(10) Å], was solved with an X-ray and refined to a final R-factor of 2.81% at room temperature. The NQR frequencies of (35)Cl and (17)O were detected with the help of the density functional theory (DFT) assigned to particular chlorine and oxygen sites in the molecules of both compounds. The NQR frequencies at (35)Cl sites in chloroxylenol and triclosan were found to be more differentiated than frequencies at the (17)O site. The former better describes the substituent withdrawing effects connected to π-electron delocalization within the benzene rings and the influence of temperature; whereas, those at the (17)O site provide more information on O-H bond and intermolecular interactions pattern. The conformation adopted by diphenyl ether of triclosan in solid state was found to be typical of diphenyl ethers, but the opposite to those adopted when it was bound to different inhibitors. According to an X-ray study, temperature had no effect on the conformation of the diphenyl ring of triclosan, which was the same at 90 K and at room temperature (RT). The scattering of NQR frequencies reproduced by the DFT under assumption of the X-ray data at 90 K and RT is found to be a good indicator of the quality of resolution of the crystallographic structure.


Subject(s)
Anti-Bacterial Agents/chemistry , Antifungal Agents/chemistry , Electrons , Nuclear Magnetic Resonance, Biomolecular/methods , Triclosan/chemistry , Xylenes/chemistry , Chlorine , Crystallography, X-Ray , Isotopes , Molecular Conformation , Oxygen Isotopes , Quantum Theory , Temperature
3.
Biochem Soc Trans ; 35(Pt 3): 512-5, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17511641

ABSTRACT

Nature is an exquisite designer of inorganic materials using biomolecules as templates. Diatoms create intricate silica wall structures with fine features using the protein family of silaffins as templates. Marine sponges create silica spicules also using proteins, termed silicateins. In recent years, our group and others have used biomolecules as templates for the deposition of inorganic materials. In contrast with the traditional materials science approach, which requires high heat, extreme pH and non-aqueous solutions, the bio-based approaches allow the reactions to proceed usually at near ambient conditions. Additionally, the biological templates allow for the control of the inorganic nanoparticle morphology. The use of peptides and biomolecules for templating and assembling inorganics will be discussed here.


Subject(s)
Chemistry, Bioinorganic/methods , Inorganic Chemicals/chemical synthesis , Amino Acid Sequence , Animals , Gold/chemistry , Inorganic Chemicals/chemistry , Microscopy, Electron , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Nanostructures/chemistry , Nanotechnology , Oligopeptides/chemistry
4.
Cryobiology ; 45(2): 143-52, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12482380

ABSTRACT

We have examined the effects of combinations between egg-phosphatidylcholine (EPC) or dipalmitoylphosphatidylcholine (DPPC) liposomes with either bovine spermatozoa or oocytes on cellular chilling sensitivity, lipid phase transition temperature (T(m)), and the ability of the oocytes to develop to the blastocyst stage. Spermatozoa and oocytes were exposed to EPC and DPPC liposomes at various temperatures (spermatozoa: 4, 12, 16, and 25 degrees C; oocytes: 4, 16, and 32 degrees C). The membrane integrity of the spermatozoa-control group decreased significantly following exposure to 16 or 12 degrees C, compared to ambient temperature (25 degrees C). In contrast, the EPC-sperm group had a greater resistance to chilling at each temperature and showed a decline in membrane integrity only at the lowest temperatures investigated. However, the DPPC-sperm group was injured significantly at all temperatures tested. Similar to the sperm, oocytes from the control group that were exposed to 16 degrees C were injured more severely than oocytes that were electrofused with EPC or DPPC liposomes. The membrane integrity of the oocytes at 16 degrees C that were electrofused with either EPC or DPPC liposomes was approximately the same as the control group held at 32 degrees C (normalized to 100%), compared to 46% in the control group at 16 degrees C (P<0.01). The transition temperatures of the sperm and oocyte membranes revealed different T(m) for the different liposome treatments. All groups had a significantly higher cleavage rate, as well as increased blastocyst formation when oocytes were exposed to temperatures above or below their T(m). We suggest that the T(m) of spermatozoa or oocytes can be changed by spontaneous association or electrofusion of liposomes with cellular membranes and, consequently, the chilling sensitivity can be altered. The resulting possibility is that embryo development after cryopreservation could be improved with such a method.


Subject(s)
Membrane Lipids/metabolism , Oocytes/metabolism , Spermatozoa/metabolism , 1,2-Dipalmitoylphosphatidylcholine , Animals , Cattle , Cold Temperature , Cryopreservation , Embryonic and Fetal Development , Female , In Vitro Techniques , Liposomes , Male , Membrane Fluidity , Phosphatidylcholines , Thermodynamics
5.
Radiat Prot Dosimetry ; 98(3): 339-42, 2002.
Article in English | MEDLINE | ID: mdl-12018750

ABSTRACT

A comparison is presented of particular methods of exposure in the first year after the Chernobyl disaster and ten years later. This comparison shows that the population exposure due to the presence of radiocaesium in the environment results from the presence of caesium contained in the soil, which provides 68% of the dose (as compared to 32% in 1987) while the influence of diet has been reduced to 32% (from 68%). The exposure from caesium-137 contained in the air has dropped from 14% to 0. The effective dose from caesium has been 50 times smaller than that from environmental sources of the natural radiation estimated for the region under study to be 1.61 mSv x y(-1).


Subject(s)
Accidents , Cesium Radioisotopes/analysis , Ecosystem , Environmental Exposure/analysis , Nuclear Reactors , Radioactive Fallout/analysis , Environmental Monitoring , Humans , Poland , Radiation Dosage , Ukraine
6.
Mycotoxin Res ; 18(2): 67-76, 2002 Jun.
Article in English | MEDLINE | ID: mdl-23606014

ABSTRACT

Inoculation experiments with 12 genotypes of oats (9 lines: CHD 894, CHD 1095, CHD 1296, CHD 1607, CHD 1653, CHD 1692, STH 2293, STH 2393, STH 2494, STH 2694 and 2 cultivars: Farys, Slawko) were performed during the vegetation seasons of 1999 - 2000 in Zamosc region in the South - Eastern part of Poland.Panicles of oats were inoculated with a conidial suspension ofFusarium avenaceum, which caused the following average reductions of traits: yield by 37.8 % and weight of 1000 kernels by 40.2 % respectively.The highest susceptibility to scab development caused by theF. avenaceum inoculation was found particularly for two lines (CHD 894, and CHD 1296) while cultivar Farys and line CHD 1607 exhibited the highest resistance to the disease in terms of TKW and yield reductions after inoculation. During 2 consecutive years (1999 and 2000 respectively) the average level of moniliformin accumulation (mg/kg) in positive samples was respectively 0.51 and 0.12 the highest being 1.11 and 0.26, while the lowest was 0.30 and 0.01.

7.
Biochim Biophys Acta ; 1511(2): 255-63, 2001 Apr 02.
Article in English | MEDLINE | ID: mdl-11286968

ABSTRACT

Over the past decade antifreeze proteins from polar fish have been shown either to stabilize or disrupt membrane structure during low temperature and freezing stress. However, there has been no systematic study on how membrane composition affects the interaction of antifreeze proteins with membranes under stress conditions. Therefore, it is not possible at present to predict which antifreeze proteins will protect, and which will damage a particular membrane during chilling or freezing. Here, we analyze the effects of freezing on spinach thylakoid membranes and on model membranes of varying lipid composition in the presence of antifreeze protein type I (AFP I) and specific fractions of antifreeze glycoproteins (AFGP). We find that the addition of galactolipids to phospholipid model membranes changes the effect each protein has on the membrane during freezing. However, the greatest differences observed in this study are between the different types of antifreeze proteins. We find that AFP type I and the largest molecular weight fractions of AFGP induce concentration dependent leakage from, and are fusogenic to the liposomes. This is the first report that an antifreeze protein induces membrane fusion. In contrast, the smallest fraction of AFGP offers a limited degree of protection during freezing and does not induce membrane fusion at concentrations up to 10 mg/ml.


Subject(s)
Antifreeze Proteins/pharmacology , Freezing , Lipid Bilayers/chemistry , Thylakoids/drug effects , Antifreeze Proteins/genetics , Antifreeze Proteins/isolation & purification , Membrane Fusion , Permeability , Spinacia oleracea
8.
J Agric Food Chem ; 48(12): 5864-7, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11141260

ABSTRACT

In most previously described membrane-based immunoassays a separate negative control assay is always carried out to evaluate the performance of the assay. To overcome this problem, a membrane-based flow-through enzyme immunoassay with an internal control has been developed for the detection of T-2 toxin in cereals (patent pending). An Immunodyne ABC membrane was coated with 2 microL of goat anti-horseradish peroxidase (HRP) (internal control spot) (1:1000) and 2 microL of rabbit anti-mouse (test spot) (undiluted) immunoglobulins, and the free binding sites were blocked. In addition to the antibody-coated Immunodyne ABC membrane, the assay also comprises a plastic snap-fit device, absorbent cotton wool, mouse anti-T-2 monoclonal antibodies (Mab), and T-2-HRP conjugate. The color intensity (Delta) of the internal control and that of the negative sample showed no difference (P > 0.05), whereas there was a significant difference between the internal control and positive samples (P < 0.05). The minimum detectable limit that could be visually detected with confidence was 50 ng of T-2 per gram of cereal sample.


Subject(s)
Edible Grain/chemistry , Food Contamination , Immunoenzyme Techniques/methods , T-2 Toxin/analysis , Edible Grain/microbiology , Fusarium/metabolism , Membranes, Artificial
9.
Rocz Akad Med Bialymst ; 39: 64-73, 1994.
Article in English | MEDLINE | ID: mdl-7497086

ABSTRACT

The paper presents the results of the measurements of natural radioactivity of building components and materials used in the North-East part of Poland performed by the Department of Biophysics, Medical Academy of Bialystok. The natural radioactivity (40K, 224Ra and 232Th) of 133 samples was measured and the qualifying coefficients f1 and f2 were calculated. All measured samples of different materials had radioactivity level below legally accepted value. The lowest values of f1 and f2 were observed in prefabricated building materials; and they were lower then in traditional red brick. Only one sample of furnace slag had increased value of natural radioactivity, which was higher than legally permitted level.


Subject(s)
Environmental Exposure/analysis , Facility Design and Construction , Materials Testing , Radon/analysis , Environmental Monitoring , Poland
10.
Przegl Lek ; 51(7): 300-2, 1994.
Article in Polish | MEDLINE | ID: mdl-7871203

ABSTRACT

The effect of furosemide (1500 mg/21 of peritoneal dialysis fluid) on excretion of hydroxyproline in dialysate and its renal clearance was investigated in 12 patients with end-stage renal disease on regular dialysis treatment. The 37 +/- 8% and 20 +/- 6% increase of D/S ratio of hydroxyproline after 5 and 8 hours of dwell, respectively, and 52 +/- 24% increase of renal clearance of hydroxyproline were induced by furosemide, which indicate its significant influence on peritoneal and renal removal of hydroxyproline.


Subject(s)
Dialysis Solutions/analysis , Furosemide/pharmacology , Hydroxyproline/drug effects , Kidney Failure, Chronic/urine , Peritoneal Dialysis , Adult , Aged , Female , Humans , Hydroxyproline/analysis , Kidney Failure, Chronic/therapy , Male , Middle Aged
11.
Gynecol Oncol ; 34(3): 350-2, 1989 Sep.
Article in English | MEDLINE | ID: mdl-2475393

ABSTRACT

Twenty-one patients with recurrent gynecologic malignancies were treated with photodynamic therapy using Photofrin II and argon dye laser. Seven of twenty-one patients with cutaneous lesions treated palliatively had a complete response and four of eleven patients with cervical and vaginal recurrences had an objective response to phototherapy. Two of the patients with complete response continued to be free of disease after 28 and 36 months of follow-up.


Subject(s)
Genital Neoplasms, Female/drug therapy , Photochemotherapy , Dihematoporphyrin Ether , Drug Evaluation , Female , Follow-Up Studies , Hematoporphyrins/therapeutic use , Humans , Neoplasm Recurrence, Local/drug therapy , Palliative Care , Photochemotherapy/adverse effects
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