To compare the therapeutic efficacy of cryopreserved amniotic membrane (AM) grafts and standard of care (SOC) in treating nonhealing wounds (NHW) through a prospective multicenter clinical trial, 42 patients (76% polymorbid) with 54 nonhealing wounds of various etiologies (mainly venous) and an average baseline size of 20 cm2 were included. All patients were treated for at least 6 weeks in the center before they were involved in the study. In the SOC group, 29 patients (36 wounds) were treated. If the wound healed less than 20% of the baseline size after 6 weeks, the patient was transferred to the AM group (35 patients, 43 wounds). Weekly visits included an assessment of the patient's condition, photo documentation, wound debridement, and dressing. Quality of life and the pain degree were subjectively reported by patients. After SOC, 7 wounds were healed completely, 1 defect partially, and 28 defects remained unhealed. AM application led to the complete closure of 24 wounds, partial healing occurred in 10, and 9 remained unhealed. The degree of pain and the quality of life improved significantly in all patients after AM application. This study demonstrates the effectiveness of cryopreserved AM grafts in the healing of NHW of polymorbid patients and associated pain reduction.
- Publikační typ
- časopisecké články MeSH
This study aimed to evaluate the efficacy of cryopreserved amniotic membrane (AM) grafts in chronic wound healing, including the mean percentage of wound closure per one AM application, and to determine whether the healing efficiency differs between AM grafts obtained from different placentas. A retrospective study analyzing inter-placental differences in healing capacity and mean wound closure after the application of 96 AM grafts prepared from nine placentas. Only the placentas from which the AM grafts were applied to patients suffering from long-lasting non-healing wounds successfully healed by AM treatment were included. The data from the rapidly progressing wound-closure phase (p-phase) were analyzed. The mean efficiency for each placenta, expressed as an average of wound area reduction (%) seven days after the AM application (baseline, 100%), was calculated from at least 10 applications. No statistical difference between the nine placentas' efficiency was found in the progressive phase of wound healing. The 7-day average wound reduction in particular placentas varied from 5.70 to 20.99% (median from 1.07 to 17.75) of the baseline. The mean percentage of wound surface reduction of all analyzed defects one week after the application of cryopreserved AM graft was 12.17 ± 20.12% (average ± SD). No significant difference in healing capacity was observed between the nine placentas. The data suggest that if there are intra- and inter-placental differences in AM sheets' healing efficacy, they are overridden by the actual health status of the subject or even the status of its individual wounds.
- MeSH
- amnion * transplantace MeSH
- hojení ran MeSH
- kryoprezervace MeSH
- lidé MeSH
- placenta * MeSH
- retrospektivní studie MeSH
- těhotenství MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Cíl: Představit použití lidské kryokonzervované amniové membrány (AM) v léčbě chronických ran, specifikovat indikační kritéria pro její aplikaci, protokol aplikace a metodiku převazů. Dalším cílem je seznámení se souhrnnými výsledky studie léčby chronických nehojících se ran pomocí AM a s predikcí zhojení dle dynamiky léčby. Materiály a metody: Standardizace léčby pomocí kryokonzervované AM proběhla v rámci multicentrické studie ve třech klinických centrech. Pacientům s chronickými ranami, kteří se nehojili v průměru po dobu 34 měsíců (minimálně šest týdnů), byla aplikována AM, s pravidelnými vizitami po sedmi dnech. Výsledky: Z 35 pacientů s 43 ranami různé etiologie, bylo po aplikaci AM zcela zhojeno 24 ran (56 %), 10 ran bylo zhojeno částečně (> 50 % plochy rány) (23 %), 9 ran (21 %) se zhojit nepodařilo. Během léčby AM zaznamenali pacienti silný analgetický účinek. Sledování dynamiky hojení vedlo ke stanovení predikčního intervalu pro posouzení schopnosti rány zhojit se pomocí AM na 10–12 týdnů. Závěr: Léčba chronických ran pomocí AM přináší prospěch indikovaným pacientům, jak v akceleraci hojení, tak ve zlepšení kvality života, a to zejména snížení bolesti v oblasti rány.
Objective: This work presents the use of human cryopreserved amniotic membrane (AM) in the treatment of chronic wounds, specifying the indication criteria for its application, application protocol, and wound dressing methodology. At the same time, it presents the summary results of the study of the treatment of chronic non-healing wounds using AM with the prediction of healing according to the dynamics of the treatment. Materials and methods: Standardization of treatment using cryopreserved AM took place within the framework of a multicentre study in three specialist centres. Patients with chronic wounds that did not heal for an average of 34 months (min. six weeks) were treated with AM, with regular visits every seven days. The AM application was carried out 1–2 times in 14 days. Results: Out of 35 patients with 43 wounds of various etiologies, 24 wounds (56%) were completely healed after AM application, 10 wounds were partially healed (> 50% of the wound area) (23%), 9 wounds (21%) failed to heal. During AM treatment, patients experienced a strong analgesic effect. Monitoring the dynamics of healing led to the establishment of a prediction interval for assessing the ability of the wound to heal using AM at 10–12 weeks. Conclusion: The treatment of chronic wounds using AM brings benefits to the indicated patients, both in the acceleration of healing and in the improvement of the quality of life, especially in the reduction of pain in the wound area.
- MeSH
- amnion * fyziologie MeSH
- biologické krytí * klasifikace MeSH
- hojení ran MeSH
- kryoprezervace metody MeSH
- lidé MeSH
- membrány fyziologie MeSH
- placenta fyziologie MeSH
- rány a poranění ošetřování terapie MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- multicentrická studie MeSH
- práce podpořená grantem MeSH
We evaluated the effect of the application of cryo-preserved amniotic membrane on the healing of 26 non-healing wounds (18 patients) with varying aetiologies and baseline sizes (average of 15.4 cm2 ), which had resisted the standard of care treatment for 6 to 456 weeks (average 88.8 weeks). Based on their average general responses to the application of cryo-preserved AM, we could differentiate three wound groups. The first healed group was characterised by complete healing (100% wound closure, maximum treatment period 38 weeks) and represented 62% of treated wounds. The wound area reduction of at least 50% was reached for all wounds in this group within the first 10 weeks of treatment. Exactly 19% of the studied wounds responded partially to the treatment (partially healed group), reaching less than 25% of closure in the first 10 weeks and 90% at maximum for extended treatment period (up to 78 weeks). The remaining 19% of treated wounds did not show any reaction to the AM application (unhealed defects). The three groups have different profiles of wound area reduction, which can be used as a guideline in predicting the healing prognosis of non-healing wounds treated with a cryo-preserved amniotic membrane.
- MeSH
- amnion * MeSH
- hojení ran * fyziologie MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Autologous serum eye drops (ASEDs) are used as a treatment for severe dry eye disease. The concentration and stability of various growth factors in ASEDs is determinative for their efficiency. We therefore assessed the concentrations of transforming growth factor beta 1 (TGF-β1), epidermal growth factor (EGF) and insulin-like growth factor 1 (IGF-1) in ASEDs following storage at 4-8, -20, -80 and -156 °C. Twenty % and 100% sera from eight healthy volunteers were analysed by the sandwich enzyme immunoassay at different time intervals up to seven months. The mean levels of TGF-β1 and EGF in undiluted and 20% serum did not differ significantly from the baseline levels in fresh serum for any storage conditions after 7 days at 4-8 °C, as well as after 4- and 7-month preservation at sub-zero temperatures. In 20% serum, no IGF-1 concentration decrease was found following 7 days of preservation at 4-8 °C. However, a decrease to 78 % and 81 % (P < 0.01) of baseline values was found in 20% serum after 4-month storage at -20 °C and 7-month storage at -156 °C, respectively. A more pronounced decrease in IGF-1 was observed in undiluted serum. All assessed growth factors present in 20% frozen serum remained stable for up to 7 months. The highest stability was achieved at -80 °C. At -20 and -156 °C, some decrease in IGF-1 occurred. Our results indicate that 20% ASEDs can be stored frozen up to 7 months under proper conditions.
PURPOSE: To assess whether the micronucleus cytome assay (MCyt) reliably detects DNA damage occurring in control and pathological superficial epithelial cells from human conjunctiva. METHODS: Impression cytology samples from the bulbar conjunctiva of 33 healthy controls, eight patients with conjunctival intraepithelial neoplasia (CIN) and eight with mucous membrane pemphigoid (MMP) were examined using the MCyt modified for the ocular surface. RESULTS: The mean number of micronuclei (MNi) in control samples was 0.94 MNi/1000 epithelial cells, with no significant difference between conjunctival quadrants and independent of sex and age. The MCyt assay applied to CIN-affected eyes showed a significantly higher frequency of MNi (18.63/1000 cells), apoptotic cells, nuclear enlargement, multinucleated cells, and keratolysis compared with the corresponding unaffected paired eyes and with the control value. Although the mean MNi frequency in MMP eyes was also higher (1.73 MNi/1000 cells), it did not prove to be statistically different from the control samples. On the other hand, the MMP-affected eyes revealed significantly elevated percentages of cells with snake-like chromatin, multinucleated cells, apoptotic cells, and nuclear buds compared with controls. CONCLUSIONS: Micronucleus cytome assay was adapted as a rapid screening test for genomic instability on the ocular surface. We have determined reference levels for MNi and other nuclear alterations on healthy conjunctiva and demonstrated that particularly frequencies of MNi are significantly elevated in conjunctiva affected by CIN. We demonstrate that MNi are more specific than other nuclear abnormalities and thus can be used for screening of ocular surface neoplasia.
- MeSH
- buněčné jádro MeSH
- epitelové buňky * MeSH
- konjunktiva MeSH
- lidé MeSH
- mikrojaderné testy MeSH
- poškození DNA * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Micro- and nanostructures prepared from biodegradable homopolymers and amphiphilic block copolymers (AmBCs) have found application as drug-delivery systems (DDSs). The ability to accumulate a drug is a very important parameter characterizing a given DDS. This work focuses on the impact of DDS size, the packing of polymer chains in the DDS, and drug - polymer matrix compatibility on the hydrophobic drug - loading capacity (DLC) of nano/microcarriers prepared from a biodegradable polymer or its copolymer. Using experimental measurements in combination with atomistic molecular dynamics simulations, an analysis of curcumin encapsulation in microspheres (MSs) from polylactide (PLA) homopolymer and nanoparticles (NPs) from PLA-block-poly(2-methacryloyloxyethylphosphorylcholine) AmBC was performed. The results show that curcumin has good affinity for the PLA matrix due to its hydrophobic nature. However, the DLC value is limited by the fact that curcumin only accumulates in the peripheral part of these structures. Such uneven drug distribution in the PLA matrix results from the non-homogeneous density of MSs (non-uniform packing of the polymer chains in the coil). The results also indicate that the MSs can retain a greater amount of hydrophobic drug compared to the NPs, which is associated with the formation of drug aggregates inside the PLA microparticles.
- MeSH
- léčivé přípravky * MeSH
- nanočástice * MeSH
- nosiče léků MeSH
- polyestery MeSH
- polyethylenglykoly MeSH
- velikost částic MeSH
- Publikační typ
- časopisecké články MeSH
The three-dimensional (3D) organization of chromatin plays a crucial role in the regulation of gene expression. Chromatin conformation is strongly affected by the composition, structural features and dynamic properties of the nucleosome, which in turn determine the nature and geometry of interactions that can occur between neighboring nucleosomes. Understanding how chromatin is spatially organized above the nucleosome level is thus essential for understanding how gene regulation is achieved. Towards this end, great effort has been made to understand how an array of nucleosomes folds into a regular chromatin fiber. This review summarizes new insights into the 3D structure of the chromatin fiber that were made possible by recent advances in cryo-electron microscopy.
The histone H3 variant CENP-A marks centromeres epigenetically and is essential for mitotic fidelity. Previous crystallographic studies of the CENP-A nucleosome core particle (NCP) reconstituted with a human α-satellite DNA derivative revealed both DNA ends to be highly flexible, a feature important for CENP-A mitotic functions. However, recent cryo-EM studies of CENP-A NCP complexes comprising primarily Widom 601 DNA reported well-ordered DNA ends. Here, we report the cryo-EM structure of the CENP-A 601 NCP determined by Volta phase-plate imaging. The data reveal that one ('left') 601 DNA end is well ordered whereas the other ('right') end is flexible and partly detached from the histone core, suggesting sequence-dependent dynamics of the DNA termini. Indeed, a molecular dynamics simulation of the CENP-A 601 NCP confirmed the distinct dynamics of the two DNA extremities. Reprocessing the image data using two-fold symmetry yielded a cryo-EM map in which both DNA ends appeared well ordered, indicating that such an artefact may inadvertently arise if NCP asymmetry is lost during image processing. These findings enhance our understanding of the dynamic features that discriminate CENP-A from H3 nucleosomes by revealing that DNA end flexibility can be fine-tuned in a sequence-dependent manner.
