Aqueous dispersions of sulfonated polystyrene nanoparticles (average diameter: 30 ± 14 nm) with encapsulated 5,10,15,20-tetraphenylporphyrin (TPP) are promising candidates for antibacterial treatments due to the photogeneration of cytotoxic singlet oxygen species O2(1Δg) under physiological conditions using visible light. The antibacterial effect on gram-negative Escherichia coli was significantly enhanced after the addition of nontoxic potassium iodide (0.001-0.01 M) because photogenerated O2(1Δg) oxidized iodide to I2/I3-, which is another antibacterial species. The improved antibacterial properties were predicted using luminescence measurements of O2(1Δg), transient absorption of TPP triplets and singlet oxygen-sensitized delayed fluorescence (SODF). In contrast to a solution of free photosensitizers, the aqueous dispersion of photoactive nanoparticles did not exhibit any quenching of the excited states after the addition of iodide or any tendency toward aggregation and/or I3--induced photo-aggregation. We also observed a decrease in the lifetime of O2(1Δg) and a significant increase in SODF intensity at higher temperatures, due to the increased oxygen diffusion coefficient in nanoparticles and aqueous surroundings. This effect corresponds with the significantly stronger antibacterial effect of nanoparticles at physiological temperature (37 °C) in comparison with that at room temperature (25 °C).
- MeSH
- antibakteriální látky farmakologie MeSH
- časové faktory MeSH
- Escherichia coli účinky léků MeSH
- fotosenzibilizující látky farmakologie MeSH
- jodidy farmakologie MeSH
- kinetika MeSH
- luminiscence MeSH
- mikrobiální testy citlivosti MeSH
- nanočástice chemie ultrastruktura MeSH
- nanovlákna chemie ultrastruktura MeSH
- teplota * MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE OF THE STUDY Osteoarthritis of the thumb's basal joint is a frequent and, in some cases, very painful condition that usually affects middle-aged and elderly women. Several surgical procedures have been proposed for severe carpometacarpal (CMC) joint arthritis; of these, joint replacement has proved to be an effective approach to its treatment. The aim of this study is to present the outcomes of the total non-cemented trapeziometacarpal implant Maïa in the treatment of more advanced stages of this disease. MATERIAL AND METHODS Thirty-six total trapeziometacarpal joint replacements in 34 patients treated in 2008 for advanced CMC arthritis (Eaton and Littler stages III and IV) were evaluated. Indications for surgery after failure of conservative treatment included: pain, reduced grip and pinch strength and restricted range of thumb motion, all of them interfering with daily activities. The average follow-up time was 42 months, with a minimum of 37 months. RESULTS At the final follow-up, thumb opposition to the base of the little finger was present in all patients. The average grip strength of the hand increased from 15.8 kg pre-operatively to 26.8 kg post-operatively The average key pinch strength increased from 2.7 kg to 5.7 kg and the average tip pinch strength from 2.3 kg to 4.9 kg. All patients reported substantial pain relief. The average VAS values were 8.4 points before surgery and 0.4 points at 3 years after surgery. Pre- and post-operative DASH scores were 71.7 and 22.5, respectively. One patient had aseptic cup loosening that required revision surgery. No signs of implant loosening in any other patient were shown by radiographic studies at the final follow-up. One patient sustained a traumatic implant dislocation that was treated by open reduction. DISCUSSION Total replacement of the CMC joint is a method with functional outcomes comparable with or better than other surgical procedures. Rapid post-surgery recovery is its clear advantage. The implant provides good stability and no prolonged immobilisation is needed. CONCLUSIONS In our group, total arthroplasty of the thumb CMC joint provided pain relief, improved thumb motion and pinch strength. At present, CMC joint arthroplasty is recommended to elderly patients with symptoms of advanced arthritis (stage III or early stage IV) refractory to conservative treatment or to well-informed younger persons accepting reduced demands on the treated hand's activities.
- MeSH
- artroplastika prstů * metody MeSH
- karpometakarpální klouby * chirurgie MeSH
- lidé MeSH
- obnova funkce MeSH
- osteoartróza chirurgie komplikace radiografie MeSH
- palec ruky * chirurgie patologie MeSH
- prospektivní studie MeSH
- protézy a implantáty * využití MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
The kinematics of an intact knee joint and that of a knee replacement have been studied in many research centres. In the 1987 radiographic study, Bradley, Goodfellow and O'Connor reported the movement of a polyethylene insert in patients with unicompartmental Oxford knee replacement. Views with the knee at full extension and 90° of flexion were obtained and the movement of the meniscal bearings over this range of flexion was measured. The bearings were found to move backwards on the tibia through an average distance of 4.4 mm in all 16 patients. This measurement was in agreement with the then valid concept of knee biomechanics and a roll-back phenomenon. However, our observations had not always agreed with the results of these authors, but gave an impetus for a detailed evaluation of our own patient group. The aim of the study was to evaluate the dynamic relationship between the components of a unicompartmental Oxford knee replacement and elucidate it with the use of recent information from the field of biomechanics. A relationship of the obtained kinematic values to clinical outcomes was also investigated. Answers to the following hypotheses were sought: Would our results be in agreement with the British authors' findings? Would clinical outcomes depend on the kinematic properties of knee replacements? MATERIAL AND METHODS The group comprised 33 patients, 23 women and 10 men. They all had replacement of the medial compartment of the knee. The construction of the unicompartmental Oxford Phase III knee replacement enabled us to locate the centre of rotation of the medial femoral condyle in relation to the tibial component at flexion and extension of the knee, using radiography. The patients were examined in a supine position with the knee at full extension, and subsequently views of the knee were obtained at 80°-90° flexion in accordance with the method used by the British authors. The clinical findings of knee joints were assessed using the American Knee Society (AKS) scoring system (Insall et al.). Pain was rated on the Visual Analogue Scale (VAS). The results were statistically evaluated with the t-test and Chi-square test. RESULTS On moving the knee from extension to flexion, movement of the polyethylene insert ventrally by an average of 3.4 mm in relation to the tibia was recorded, i.e., "paradoxical" ventral translocation. In the patients with insert movement less than or equal to 3 mm, the average AKS score was 89 points, in those with movement over 3 mm it was 87 points. The average functional scores were 87 and 83 points in the patients with movement less than 3 mm and more than 3 mm, respectively. The average VAS score was 1.55 in the former and 1.18 in the latter. DISCUSSION The unicompartmental Oxford Phase III knee replacement substitutes a flexion femoral facet and eliminates the role of an extension femoral facet. This is the reason why, at knee extension between -5° and +20°, the centre of rotation of the medial femoral condyle is in the centre of the flexion facet and not in that of the extension facet. When the stabilising functions of the extension tibial facet in the ventral direction and of the dorsal part of the insert in the dorsal direction are missing, the position of the contact surface centre becomes much dependent also on the strength and direction of external forces acting in the knee joint vicinity. CONCLUSIONS The kinematic parameters of the unicompartmental Oxford Phase III knee replacement investigated in our group differed from the findings of the British authors. However, neither the magnitude nor the direction of movement had any effect on the clinical outcome of knee arthroplasty.
- MeSH
- biomechanika MeSH
- kolenní kloub patofyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- protézy kolene MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- totální endoprotéza kolene MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
Tetraphenylporphyrin conjugates with one (PB1) and four (PB4) cobalt(III) bis(1,2-dicarbollide) substituents were synthesized and the physicochemical and photophysical properties as well as inhibition of HIV-1 protease were described. In methanol, both PB1 and PB4 were monomeric producing the triplet states and singlet oxygen after excitation. The triplet states of PB4 were quickly protonated. Porphyrins exhibited a small decrease of the quantum yields of the singlet oxygen formation (17% for PB4 and 13% for PB1) as compared with 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin. On the contrary, no singlet oxygen was detected in aqueous solutions because of strong aggregation. Light scattering and atomic force microscopy (AFM) measurements documented that the behavior of aggregates in aqueous solutions is fairly complex and depends on pH, concentration, and aging. The aggregation started from spherical particles in neutral solutions. In acidic solutions, extended aggregation occurred because of slow protonation of the porphyrin pyrrole nitrogen atoms. Both PB1 and PB4 are new representatives of nonpeptide HIV-1 protease inhibitors. Their activity increased with the increasing number of the cobalt(III) bis(1,2-dicarbollide) substituents and was characterized with the IC50 values of 290+/-44 nM for PB1 and 77+/-13 nM for PB4.
- MeSH
- financování organizované MeSH
- HIV-proteasa metabolismus MeSH
- inhibiční koncentrace 50 MeSH
- inhibitory HIV-proteasy farmakologie chemie MeSH
- kyslík chemie MeSH
- mikroskopie atomárních sil MeSH
- molekulární modely MeSH
- molekulární struktura MeSH
- organokovové sloučeniny chemie MeSH
- porfyriny farmakologie chemie MeSH
- sloučeniny boru chemie MeSH
- substrátová specifita MeSH
Autoři hodnotí soubor 57 pacientů s ruptúrou předního zkříženého vazu (dále PZV). První skupinu tvoří 23 pacientů, u kterých byla akutní ruptúra PZV řešena suturou. Druhou skupinu tvoří 35 pacientů s verifikovanou neošetrenou kompletní lézí PZV. K srovnání použili Lysholmovo skóre, předozadní instabilitu Objektivizovali přístrojem KT 1000. Sledovali rozsah omezení pohybu kolenního kloubu. Průměrná hodnota Lyshoimova skóre byla v první skupině 84 bodů, ve druhé 80,7 bodu. Průměrný posun tibie vůči femuru činil 11,2 mm u pacientů po suture vazu a 12 mm u pacientů s neošetreným vazem. U 4 pacientů první skupiny přetrvává významné omezení rozsahu flexe kolenního kloubu. Autoři na základě těchto výsledků a literárních údajů suturu PZV opustili, instabilitu řeší v indikovaných případech náhradou PZV.
The authors evaluate a group of 57 patients with rupture of the anterior cruciatee ligament (ACL). The first group is formed by 23 patients where the acute ACL rupture was treated by suture. The second group omprises 35 patients with a confirmed untreated complete ACL lesion. For comparison Lysholm's score was used; anteroposterior instability was assessed obiectiveiy by a KT apparatus. The authors investigated the range of movements of the knee joint. The mean value of Lysholm's score in the first group was 84 points, in the second group 80.7 points. The mean shift of the tibia in relation to the femur was 11.2 mm in patients after suture of the ligament and 12 mm in patients with an untreated ligament. In four patients of the first group a significantly restricted range of flexion of the knee joint persists. Based on these results and data in the literature the authors abondoned suture of the ACL and resolved instability in indicated cases by replacement of the ACL.
- MeSH
- dospělí MeSH
- lidé MeSH
- ligamentum cruciatum anterius chirurgie MeSH
- ortopedie metody MeSH
- poranění kolena diagnóza terapie MeSH
- poranění předního zkříženého vazu MeSH
- ruptura MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
