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1.
Medicina (Kaunas) ; 60(7)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39064613

RESUMO

Background and Objectives: Biodex System® is an advanced dynamometer used for testing various biomechanical parameters of muscles. Test outcomes allow for the identification of muscle pathology and consequently lead to a clinical diagnosis. Despite being widely used for the testing and rehabilitation of the human musculoskeletal system, no universal and acceptable protocol for wrist examination has been proposed for patients with wrist pathology. In this study, the authors aim to identify the most appropriate protocol for testing the biomechanical parameters of flexors and extensors of the wrist. Materials and Methods: A group of 20 patients with symptomatic tennis elbow and 26 healthy volunteers were examined using three different protocols: isokinetic, isometric and isotonic. Protocol order for each study participant was assigned at random with a minimum of a 24 h break between protocols. All protocol parameters were set according to data obtained from a literature review and an earlier pilot study. Following completion of each protocol, participants filled out a questionnaire-based protocol, assessing pain intensity during the exam, difficulty with exam performance and post-exam muscle fatigue. Results: The isotonic protocol showed the best patient tolerance and the highest questionnaire score. There was a significant difference (p < 0.05) between the three protocols in average pain intensity reported by study participants. All participants completed the isotonic protocol, but not all patients with symptomatic tennis elbow were able to complete the isometric and isokinetic protocols. The isotonic protocol was deemed "difficult but possible to complete" by study participants. Conclusions: The isotonic protocol is most suitable for testing the flexors and extensors of the wrist. It gives the most biomechanical data of all protocols, is well tolerated by patients and rarely causes pain during examination even in symptomatic participants.


Assuntos
Dinamômetro de Força Muscular , Cotovelo de Tenista , Punho , Humanos , Masculino , Adulto , Feminino , Fenômenos Biomecânicos , Cotovelo de Tenista/fisiopatologia , Cotovelo de Tenista/diagnóstico , Punho/fisiologia , Punho/fisiopatologia , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Músculo Esquelético/fisiopatologia , Contração Isométrica/fisiologia , Inquéritos e Questionários , Contração Isotônica/fisiologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-35742239

RESUMO

Algal blooms are an emerging problem. The massive development of phytoplankton is driven partly by the anthropogenic eutrophication of aquatic ecosystems and the expansion of toxic cyanobacteria in planktonic communities in temperate climate zones by the continual increase in global temperature. Cyanobacterial harmful algal blooms (CyanoHABs) not only disturb the ecological balance of the ecosystem, but they also prevent the use of waterbodies by humans. This study examines the cause of an unusual, persistent bloom in a recreational, flow-through reservoir; the findings emphasize the role played by the river supplying the reservoir in the formation of its massive cyanobacterial bloom. Comprehensive ecosystem-based environmental studies were performed, including climate change investigation, hydrochemical analysis, and bio-assessment of the ecological state of the river/reservoir, together with monitoring the cyanobacteria content of phytoplankton. Our findings show that the persistent and dominant biomass of Microcystis was related to the N/P ratio, while the presence of Aphanizomenon and Dolichospermum was associated with the high-temperature end electric conductivity of water. Together with the increase in global temperature, the massive and persistent cyanobacterial bloom appears to be maintained by the inflow of biogenic compounds carried by the river and the high electric conductivity of water. Even at the beginning of the phenomenon, the reservoir water already contained cyanobacterial toxins, which excluded its recreational use for about half the year.


Assuntos
Cianobactérias , Ecossistema , Biodiversidade , Eutrofização , Proliferação Nociva de Algas , Humanos , Lagos , Fitoplâncton , Temperatura , Água
3.
Life (Basel) ; 12(2)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35207513

RESUMO

Cyanobacteria produce a range of toxic secondary metabolites that affect many processes in human, animal and also plant cells. In recent years, some efforts have concentrated on deepening the understanding of their effect on living cells in the context of the disruption of antioxidant systems. Many results suggest that cyanotoxins interfere with glutathione (GSH) metabolism, which often leads to oxidative stress and, in many cases, cell death. Knowledge about the influence of cyanotoxins on enzymes involved in GSH synthesis or during its antioxidant action is relatively broad. However, to date, there is no information about the antioxidant properties of GSH after its direct interaction with cyanotoxins. In this paper, we investigated the effect of four cyanotoxins belonging to the groups of hepatotoxins (microcystin-LR and nodularin) or neurotoxins (anatoxin-a and ß-N-methylamino-L-alanine) on the in vitro antioxidant properties of GSH. Moreover, the same study was performed for domoic acid (DA) produced by some diatoms. The obtained results showed that none of the studied compounds had an effect on GSH antioxidant potential. The results presented in this paper are, to the best of our knowledge, the first description of the kinetics of scavenging radicals by GSH reactions under the influence of these cyanotoxins and DA. This work provides new and valuable data that broadens the knowledge of the impact of cyanotoxins and DA on GSH metabolism and complements currently available information. Future studies should focus on the effects of the studied compounds on antioxidant systems in vivo.

4.
Curr Med Chem ; 29(21): 3806-3814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35081884

RESUMO

AIM: The aim of this study was to assess the analgesic efficacy and safety of 1 mg and 0.5 mg oxycodone administration in a spinal block procedure for a total hip arthroplasty (THA). PATIENTS AND METHODS: Forty-two THA patients aged 59-81 with American Society Anesthesiology (ASA) II-III were included. All patients received anesthesia using spinal blockade, with bupivacaine 0.5% spinal heavy 2.5 ml, with 0.5 ml oxycodone hydrochloride 1.0 mg (group A; n = 28) or 0.5 mg (group B; n = 14). During surgery, each patient was sedated with 2-4 mg/kg/h intravenous propofol infusion. They received 100 mg intravenous ketoprofen at the end of the surgery at 8 pm and 8 am, with recommended doses every 12 h thereafter. Subcutaneous morphine 5 mg was used as a rescue analgesic, and the time to morphine use was recorded. After surgery, pain intensity (at the moment of patient report) was assessed using an 11-point numerical rating scale (NRS). The incidence of adverse effects was monitored. Blood samples were taken for assays of serum oxycodone, noroxycodone and bupivacaine levels. RESULTS: The time to rescue analgesia was 9.6 ± 5.6 h in group A and 7.3 ± 1.9 h in group B, and it did not differ between patient groups (P = 0.179). The mean NRS pain score was 4.5 in group A and 4.2 in group B. Three group A patients had detectable oxycodone levels: two < 7.1 ng/ml and in 1 spinal block induced anesthesia was unsuccessful and so he/she underwent general anesthesia (this patient was excluded from the analysis). Four group B patients had single values < 5 ng/ml. Noroxycodone levels were in all patients undetectable, and bupivacaine levels were 70-300 ng/ml. Regarding adverse effects, one patient had hypotension, one had bradycardia, and one had pruritus. CONCLUSION: Oxycodone in spinal block prolongs analgesia period, does not cause serious adverse effects and seems to be safe and effective opioid for patients undergoing THA.


Assuntos
Artroplastia de Quadril , Oxicodona , Analgésicos Opioides/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Bupivacaína/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Morfina/uso terapêutico , Oxicodona/efeitos adversos , Dor Pós-Operatória/induzido quimicamente , Dor Pós-Operatória/tratamento farmacológico
5.
Sci Total Environ ; 765: 142670, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069473

RESUMO

Toxins produced by cyanobacteria (cyanotoxins) are among the most dangerous natural compounds. In recent years, there have been many published papers related to the toxic alkaloids cylindrospermopsin (CYN) and anatoxin-a (ANTX-a), which are synthesized by several freshwater species of cyanobacteria (i.e. Raphidiopsis raciborskii and Anabaena flos-aquae) and are some of the most common cyanotoxins in aquatic reservoirs. The harmful properties of CYN are wide and primarily include cytotoxicity. To date, several analogs and decomposition products of CYN have been described, which can potentially increase its toxic effects in living organisms. The mode of action of ANTX-a is different than that observed after CYN exposure and involves structures in the nervous system. One of the most frequent situations in which cyanotoxins are introduced into the human body is by skin contact with contaminated water, i.e., during water sports, fishing or agriculture. Unfortunately, to date, knowledge on the influence of CYN, its decomposition products, and ANTX-a on human skin is limited. In this paper, we investigated the impact of CYN, its decomposition products, and ANTX-a on the proliferation of human keratinocytes, which provide a protective barrier on the skin. Moreover, we described the cytotoxic effects developed in the selected cell type and estimated the ability of the keratinocytes to migrate under the influence of the studied cyanotoxins. The obtained results suggest that CYN and its decomposition products at concentrations corresponding to that determined for CYN in nature (1 µg·mL-1) are strong inhibitors of keratinocyte proliferation (70% inhibition within 24 h for pure CYN). The cytotoxic effects of CYN and the CYN decomposition products on keratinocytes was also significant, and the pure toxin (1 µg·mL-1) was estimated to be 35% after 24 h of exposure. Similarly, harmful effects caused by CYN and its byproducts were observed during keratinocyte migration, and the initial form of the toxin (1 µg·mL-1) showed 40% inhibition within 16 h. Different results were obtained for ANTX-a. The toxic effects of this compound on human keratinocytes estimated by the applied tests was observed only at the highest tested concentration (10 µg·mL-1) and after a long period of exposure. The results presented in this paper are, to the best of our knowledge, the first description of the influence of CYN, CYN decomposition products, and ANTX-a on human epidermal cells. Clearly, CYN and its decomposition products are serious threats not only when acting on internal organs but also during the skin contact stage. Further studies on cyanotoxins should focus on the determination of their decomposition products and ecotoxicology in natural aquatic environments.


Assuntos
Queratinócitos , Microcistinas , Alcaloides , Toxinas de Cianobactérias , Cylindrospermopsis , Humanos , Tropanos
6.
Harmful Algae ; 98: 101894, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33129452

RESUMO

Cylindrospermopsin (CYN) is a toxic secondary metabolite produced by several freshwater species of cyanobacteria. Its high chemical stability and wide biological activity pose a series of threats for human and animal morbidity and mortality. The biggest risk of CYN exposure for human organism comes from the consumption of contaminated water, fish or seafood. Very important for effective monitoring of the occurrence of CYN in aquatic environment is accurate identification of cyanobacteria species, that are potentially able to synthesize CYN. In this review we collect data about the discovery of CYN production in cyanobacteria and present the morphological changes between all its producers. Additionally we set together the results describing the catalytic decomposition of CYN.


Assuntos
Alcaloides , Toxinas Bacterianas , Cianobactérias , Animais , Toxinas de Cianobactérias , Uracila
7.
J Pain Res ; 12: 1847-1854, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354333

RESUMO

Introduction: Rectal tenesmus pain in cancer patients most frequently appears in patients with colon cancer, and as a consequence of radiotherapy of the hypogastrium region. Treatment with opioids and adjuvant analgesics is often ineffective. Patients and methods: Here, we report on two female patients diagnosed with colon and ovary cancer, respectively, who had very severe tenesmus pain (numerical rating scale 8-10) despite using high doses of opioids, including methadone with corticosteroids, anticonvulsants, antidepressants and ketamine. Results: In both patients, bupivacaine was administered via a rectal enema. In the first patient, bupivacaine was administered at a dose of 100 mg 0.1% (100 mL), and subsequently 100 mg 0.2% (50 mL), leading to effective analgesia for 8 and 12 hrs, respectively. In the second patient, 100 mg 0.1% (100 mL) was initially administered, followed by 100 mg 0.2% (50 mL), leading to effective analgesia for 12 and 17 hrs, respectively, with only dull abdominal pain reported that was relieved by 100 mg IV ketoprofen and complete disappearance of tenesmus pain. Rectal bupivacaine administration did not cause neurologic adverse effects, heart function disturbances or decreased blood pressure. A volume of 50 mL was enough to cover a painful area in the colon. Initial bupivacaine concentrations in the blood serum did not exceed 50 ng/mL and eventually dropped to 20 ng/mL and below. Conclusions: Administration of 100 mg bupivacaine as a rectal enema is safe and provides effective analgesia, and this procedure may be conducted in hospital departments and out-patient clinics. Furthermore, this procedure in the case of pain recurrence, can be repeated, and by providing effective pain relief often allows time for the patient to be transferred to a specialized pain center.

8.
J Vis Exp ; (135)2018 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-29912197

RESUMO

The autologous, synthetic, and animal-derived grafts currently used as scaffolds for tissue replacement have limitations due to low availability, poor biocompatibility, and cost. Plant tissues have favorable characteristics that make them uniquely suited for use as scaffolds, such as high surface area, excellent water transport and retention, interconnected porosity, preexisting vascular networks, and a wide range of mechanical properties. Two successful methods of plant decellularization for tissue engineering applications are described here. The first method is based on detergent baths to remove cellular matter, which is similar to previously established methods used to clear mammalian tissues. The second is a detergent-free method adapted from a protocol that isolates leaf vasculature and involves the use of a heated bleach and salt bath to clear the leaves and stems. Both methods yield scaffolds with comparable mechanical properties and low cellular metabolic impact, thus allowing the user to select the protocol which better suits their intended application.


Assuntos
Folhas de Planta/química , Plantas/química , Engenharia Tecidual/métodos , Animais , Alicerces Teciduais
9.
J Pain Res ; 10: 2303-2309, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29026333

RESUMO

BACKGROUND AND OBJECTIVES: Oxycodone is poorly studied as an adjuvant to central blockades. The aim of this pilot study was to assess the efficacy and safety of oxycodone hydrochloride in epidural blockade among patients undergoing total hip arthroplasty (THA). PATIENTS AND METHODS: In 11 patients (American Society of Anesthesiologists physical status classification system II/III, age range: 59-82 years), THA was conducted with an epidural blockade using 15 mL 0.25% bupivacaine (37.5 mg) with 5 mg oxycodone hydrochloride and sedation with propofol infusion at a dose of 3-5 mg/kg/h. After the surgery, patients received ketoprofen at a dose of 100 mg twice daily. In the first 24 hours postoperative period, pain was assessed by numerical rating scale at rest and on movement; adverse effects (AEs) were recorded; and plasma concentrations of oxycodone, noroxycodone, and bupivacaine were measured. RESULTS: The administration of epidural oxycodone at a dose of 5 mg in patients undergoing THA provided analgesia for a mean time of 10.3±4.89 h. In one patient, mild pruritus was observed. Oxycodone did not evoke other AEs. Plasma concentrations of oxycodone while preserving analgesia were >2.9 ng/mL. Noroxycodone concentrations in plasma did not guarantee analgesic effect. CONCLUSION: The administration of epidural oxycodone at a dose of 5 mg prolongs the analgesia period to ~10 hours in patients after THA. Oxycodone may evoke pruritus. A 5 mg dose of oxycodone hydrochloride used in an epidural blockade seems to be a safe drug in patients after THA.

10.
Mar Drugs ; 15(10)2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-29065484

RESUMO

Human skin is constantly exposed to damaging ultraviolet radiation (UVR), which induces a number of acute and chronic disorders. To reduce the risk of UV-induced skin injury, people apply an additional external protection in the form of cosmetic products containing sunscreens. Nowadays, because of the use of some chemical filters raises a lot of controversies, research focuses on exploring novel, fully safe and highly efficient natural UV-absorbing compounds that could be used as active ingredients in sun care products. A promising alternative is the application of multifunctional mycosporine-like amino acids (MAAs), which can effectively compete with commercially available filters. Here, we outline a complete characterization of these compounds and discuss their enormous biotechnological potential with special emphasis on their use as sunscreens, activators of cells proliferation, anti-cancer agents, anti-photoaging molecules, stimulators of skin renewal, and functional ingredients of UV-protective biomaterials.


Assuntos
Aminoácidos/farmacologia , Organismos Aquáticos/química , Regeneração/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Neoplasias Cutâneas/prevenção & controle , Pele/efeitos dos fármacos , Aminoácidos/química , Aminoácidos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Biotecnologia/métodos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Humanos , Oceanos e Mares , Pele/efeitos da radiação , Neoplasias Cutâneas/etiologia , Queimadura Solar/prevenção & controle , Protetores Solares/química , Protetores Solares/farmacologia , Protetores Solares/uso terapêutico , Raios Ultravioleta/efeitos adversos
11.
Adv Healthc Mater ; 6(8)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28319334

RESUMO

The commercial success of tissue engineering products requires efficacy, cost effectiveness, and the possibility of scaleup. Advances in tissue engineering require increased sophistication in the design of biomaterials, often challenging the current manufacturing techniques. Interestingly, several of the properties that are desirable for biomaterial design are embodied in the structure and function of plants. This study demonstrates that decellularized plant tissues can be used as adaptable scaffolds for culture of human cells. With simple biofunctionalization technique, it is possible to enable adhesion of human cells on a diverse set of plant tissues. The elevated hydrophilicity and excellent water transport abilities of plant tissues allow cell expansion over prolonged periods of culture. Moreover, cells are able to conform to the microstructure of the plant frameworks, resulting in cell alignment and pattern registration. In conclusion, the current study shows that it is feasible to use plant tissues as an alternative feedstock of scaffolds for mammalian cells.


Assuntos
Técnicas de Cultura de Células/métodos , Marantaceae/química , Células-Tronco Mesenquimais/metabolismo , Petroselinum/química , Alicerces Teciduais/química , Linhagem Celular , Humanos , Células-Tronco Mesenquimais/citologia
12.
Phytochemistry ; 118: 116-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26342621

RESUMO

Lichen species typically have a characteristic profile of secondary metabolites. Dense populations of Hypogymnia physodes growing frequently as epiphytes on tree branches have harmful effects on the host, likely due to their secondary compounds, which were undetected in tree tissues until now. The aim of the present study was to re-characterise the suite of secondary metabolites of H. physodes thalli and to estimate their translocation into spruce (Picea abies) bark. Thallus and bark extracts were compared using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The compounds were identified based on their UV, MS and MS/MS spectra as well as retention factors of their TLC analysis. In addition to the previously described secondary metabolites (protocetraric, physodalic, 3-hydroxyphysodic, physodic, and 2'-O-methylphysodic acids, atranorin and chloroatranorin) of H. physodes, further three were identified in its thalli: conphysodalic, 4-O-methylphysodic and α-alectoronic acids. Fragmentation patterns from the negative ionisation of each compound were proposed, some of which were described for the first time. Among all of the detected lichen substances, a few, e.g., physodalic, 3-hydroxyphysodic, physodic acids and atranorin, were present in the bark of spruce branches that were abundantly colonised by lichen. The newly identified compounds of H. physodes thalli may belong to its constant or accessory secondary metabolites. These compounds may be useful in the chemotaxonomic classification of this species. The presence of some lichen substances in spruce bark confirmed their ability to penetrate host tissues. These data suggest that H. physodes compounds may cause long-term effects on spruces in nature.


Assuntos
Abies/química , Líquens/química , Picea/química , Casca de Planta/química , Dibenzoxepinas/análise , Estrutura Molecular , Espectrometria de Massas em Tandem , Árvores/química
13.
Toxicon ; 101: 35-40, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25937338

RESUMO

In the polar regions cyanobacteria are an important element of plant communities and represent the dominant group of primary producers. They commonly form thick highly diverse biological soil crusts that provide microhabitats for other organisms. Cyanobacteria are also producers of toxic secondary metabolites. In the present study we demonstrated that biocrust-forming cyanobacteria inhabiting the Kaffiøyra Plain, the north-west coast of Spitsbergen, are able to synthesize toxins, especially microcystins (MCs, from 0.123 to 11.058 µg MC-LR per g dry weight, DW) and anatoxin-a (ANTX-a, from 0.322 to 0.633 µg ANTX-a per g DW). To the best of our knowledge, this is the first report on the presence of ANTX-a in the entire polar region. The occurrence of cyanotoxins can exert a long-term impact on organisms co-existing in biocrust communities and can have far-reaching consequences for the entire polar ecosystem.


Assuntos
Cianobactérias/metabolismo , Microcistinas/isolamento & purificação , Tropanos/isolamento & purificação , Regiões Árticas , Biomassa , Cianobactérias/classificação , Toxinas de Cianobactérias , Ecossistema , Água Doce/microbiologia , Microcistinas/metabolismo , Tropanos/metabolismo
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