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OBJECTIVE: The aim: To highlight the original experience of diagnosis and treatment of patients with gunshot wounds of the extremities with extensive defects of the soft tissues. PATIENTS AND METHODS: Materials and methods: The total number of treated patients with massive gunshot wounds from February 2022 to March 2023 was 60 males. Basic labo¬ratory tests, X-rays of the affected limbs were performed to all patients. USS of the vessels with color Doppler was performed to those casualties who had no peripheral pulses on the wounded extremity. All injured persons underwent wound debridement and fasciotomy on the day of admission, 8 more casualties underwent surgical interventions on the major vessels and nerves. RESULTS: Results: Good treatment outcomes for patients with extensive soft tissue injury were achieved by early surgical intervention to remove non-viable tissue. Limb preservation was achieved in 98.3% of cases. CONCLUSION: Conclusions: The study's conclusion emphasizes the importance of a multidisciplinary approach to treating patients with gunshot wounds to the limbs with extensive soft tissue injury. Early surgical interventions with the removal of non-viable tissues are necessary for good outcomes. Revascularization of the affected limb is essential in case of major vessel injury if there is no thread to the life.
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Lesões dos Tecidos Moles , Ferimentos por Arma de Fogo , Masculino , Humanos , Ferimentos por Arma de Fogo/cirurgia , Extremidades/cirurgia , Desbridamento , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento , Estudos RetrospectivosRESUMO
OBJECTIVE: The aim: To study the level of expression of type I, III collagen under conditions of traumatic damage to integumentary tissues and to develop quantitative criteria for collagen formation processes for choosing the volume of reconstruction of a wound defect. PATIENTS AND METHODS: Materials and methods: Studies were performed for 62 victims. Clinical group 1 (n = 16) - patients with wound surface sizes of the body surface area, group 2 (n = 32) consisted of patients who received integumentary tissue defects due to or together with damage osteoarticular apparatus of the limb, group 3 (n = 14) - patients with combined trauma. RESULTS: Results: In the skin samples of patients of groups 1 and 2 of the affected groups, a statistically significant difference was established between the indicators of the relative accumulation area of type I, type III collagen (W = 675, p = 0.01 and W = 697, p = 0.03, respectively). In patients of groups 2 and 3, when analyzing relationships, a direct moderate strength was observed between the areas of collagen deposition of type I, type III (rs = 0.52 and 0.54). Collagen deposition coefficient (Ðd) was used as a quantitative criterion for assessing the prognosis of the results of restoration of integumentary tissues according to the proposed scale, which made it possible to obtain postoperative complications in only 3.2 % of cases. CONCLUSION: Conclusions: A positive treatment result taking into account the quantitative criterion (Kd) was obtained in 96.8 % of the examined patients.
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Colágeno , Cicatrização , Humanos , PeleRESUMO
Recent improvements in both X-ray detectors and readout speeds have led to a substantial increase in the volume of X-ray fluorescence data being produced at synchrotron facilities. This in turn results in increased challenges associated with processing and fitting such data, both temporally and computationally. Herein an abridging approach is described that both reduces and partially integrates X-ray fluorescence (XRF) data sets to obtain a fivefold total improvement in processing time with negligible decrease in quality of fitting. The approach is demonstrated using linear least-squares matrix inversion on XRF data with strongly overlapping fluorescent peaks. This approach is applicable to any type of linear algebra based fitting algorithm to fit spectra containing overlapping signals wherein the spectra also contain unimportant (non-characteristic) regions which add little (or no) weight to fitted values, e.g. energy regions in XRF spectra that contain little or no peak information.
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Algoritmos , Síncrotrons , Fluorescência , Radiografia , Raios XRESUMO
Arsenate is a notorious toxicant that is known to disrupt multiple biochemical pathways. Many microorganisms have developed mechanisms to detoxify arsenate using the ArsC-type arsenate reductase, and some even use arsenate as a terminal electron acceptor for respiration involving arsenate respiratory reductase (Arr). ArsC-type reductases have been studied extensively, but the phylogenetically unrelated Arr system is less investigated and has not been characterized from Archaea Here, we heterologously expressed the genes encoding Arr from the crenarchaeon Pyrobaculum aerophilum in the euryarchaeon Pyrococcus furiosus, both of which grow optimally near 100°C. Recombinant P. furiosus was grown on molybdenum (Mo)- or tungsten (W)-containing medium, and two types of recombinant Arr enzymes were purified, one containing Mo (Arr-Mo) and one containing W (Arr-W). Purified Arr-Mo had a 140-fold higher specific activity in arsenate [As(V)] reduction than Arr-W, and Arr-Mo also reduced arsenite [As(III)]. The P. furiosus strain expressing Arr-Mo (the Arr strain) was able to use arsenate as a terminal electron acceptor during growth on peptides. In addition, the Arr strain had increased tolerance compared to that of the parent strain to arsenate and also, surprisingly, to arsenite. Compared to the parent, the Arr strain accumulated intracellularly almost an order of magnitude more arsenic when cells were grown in the presence of arsenite. X-ray absorption spectroscopy (XAS) results suggest that the Arr strain of P. furiosus improves its tolerance to arsenite by increasing production of less-toxic arsenate and nontoxic methylated arsenicals compared to that by the parent.IMPORTANCE Arsenate respiratory reductases (Arr) are much less characterized than the detoxifying arsenate reductase system. The heterologous expression and characterization of an Arr from Pyrobaculum aerophilum in Pyrococcus furiosus provides new insights into the function of this enzyme. From in vivo studies, production of Arr not only enabled P. furiosus to use arsenate [As(V)] as a terminal electron acceptor, it also provided the organism with a higher resistance to arsenate and also, surprisingly, to arsenite [As(III)]. In contrast to the tungsten-containing oxidoreductase enzymes natively produced by P. furiosus, recombinant P. aerophilum Arr was much more active with molybdenum than with tungsten. It is also, to our knowledge, the only characterized Arr to be active with both molybdenum and tungsten in the active site.
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Proteínas Arqueais/genética , Arseniato Redutases/genética , Regulação da Expressão Gênica em Archaea , Pyrococcus furiosus/genética , Thermoproteaceae/genética , Proteínas Arqueais/metabolismo , Arseniato Redutases/metabolismo , Arsênio/metabolismo , Microrganismos Geneticamente Modificados/enzimologia , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Pyrococcus furiosus/enzimologia , Pyrococcus furiosus/metabolismoRESUMO
Maternal transfer of elevated selenium (Se) to offspring is an important route of Se exposure for fish in the natural environment. However, there is a lack of information on the tissue specific spatial distribution and speciation of Se in the early developmental stages of fish, which provide important information about Se toxicokinetics. The effect of maternal transfer of Se was studied by feeding adult zebrafish a Se-elevated or a control diet followed by collection of larvae from both groups. Novel confocal synchrotron-based techniques were used to investigate Se within intact preserved larvae. Confocal X-ray fluorescence imaging was used to compare Se distributions within specific planes of an intact larva from each of the two groups. The elevated Se treatment showed substantially higher Se levels than the control; Se preferentially accumulated to highest levels in the eye lens, with lower levels in the retina, yolk and other tissues. Confocal X-ray absorption spectroscopy was used to determine that the speciation of Se within the eye lens of the intact larva was a selenomethionine-like species. Preferential accumulation of Se in the eye lens may suggest a direct cause-and-effect relationship between exposure to elevated Se and Se-induced ocular impairments reported previously. This study illustrates the effectiveness of confocal X-ray fluorescence methods for investigating trace element distribution and speciation in intact biological specimens.
Assuntos
Cristalino/metabolismo , Selênio/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Feminino , Larva , Exposição Materna , Imagem Óptica , Espectroscopia por Absorção de Raios X , Peixe-ZebraRESUMO
This study aimed to develop and implement a universal method for the quantitative assessment of treatment effectiveness in patients with skin and underlying soft tissue defects of the trunk and extremities. The study involved 242 patients, including 46 patients with upper extremity injuries, 179 with lesions of lower extremity tissues, and 17 patients with defects of the integumentary tissues of the trunk. The greatest treatment effectiveness was observed in patients with upper limb injury: excellent result - 60.0%, good - 33.3%, unsatisfactory - 6.7% of patients. In the group of patients with lower extremity injuries, an excellent result was recorded in 19.6% of cases, good (58.1%), satisfactory (15.1%), and unsatisfactory in 7.2% of patients. In patients with trunk injuries, an excellent treatment result was obtained in 23.5%, good - 35.5%, satisfactory - 23.5%, and unsatisfactory - 17.6%. The universal quantitative method for evaluating treatment effectiveness in patients with various types of damage to the trunk and extremities tissues was proposed. This method makes it possible to objectively determine the level of medical service provided to each patient, which is of great importance in the context of medical service reorganization in the state.
Assuntos
Traumatismos da Perna , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Lesões dos Tecidos Moles/cirurgia , Pele/patologia , Extremidade Inferior/cirurgia , Traumatismos da Perna/patologia , Traumatismos da Perna/cirurgia , Resultado do Tratamento , Transplante de PeleRESUMO
Hundreds of millions of people worldwide are exposed to unacceptable levels of carcinogenic inorganic arsenic. Animal models have shown that selenium and arsenic are mutually protective through the formation and elimination of the seleno-bis(S-glutathionyl) arsinium ion [(GS)2AsSe]-. Consistent with this, human selenium deficiency in arsenic-endemic regions is associated with arsenic-induced disease, leading to the initiation of human selenium supplementation trials. In contrast to the protective effect observed in vivo, in vitro studies have suggested that selenite increases arsenite cellular retention and toxicity. This difference might be explained by the rapid conversion of selenite to selenide in vivo. In the current study, selenite did not protect the human hepatoma (HepG2) cell line against the toxicity of arsenite at equimolar concentrations, however selenide increased the IC50 by 2.3-fold. Cytotoxicity assays of arsenite + selenite and arsenite + selenide at different molar ratios revealed higher overall mutual antagonism of arsenite + selenide toxicity than arsenite + selenite. Despite this protective effect, in comparison to 75Se-selenite, HepG2 cells in suspension were at least 3-fold more efficient at accumulating selenium from reduced 75Se-selenide, and its accumulation was further increased by arsenite. X-ray fluorescence imaging of HepG2 cells also showed that arsenic accumulation, in the presence of selenide, was higher than in the presence of selenite. These results are consistent with a greater intracellular availability of selenide relative to selenite for protection against arsenite, and the formation and retention of a less toxic product, possibly [(GS)2AsSe]-.
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Arsenitos/toxicidade , Substâncias Protetoras/farmacologia , Ácido Selenioso/farmacologia , Compostos de Selênio/farmacologia , Arsênio/metabolismo , Arsenitos/metabolismo , Células Hep G2 , Humanos , Inativação Metabólica/efeitos dos fármacos , Substâncias Protetoras/metabolismo , Radioisótopos/metabolismo , Ácido Selenioso/metabolismo , Selênio/metabolismo , Compostos de Selênio/metabolismo , Radioisótopos de Selênio/metabolismoRESUMO
Arsenic contamination is a major environmental issue, as it may lead to serious health hazard. The reduced trivalent form of inorganic arsenic, arsenite, is in general more toxic to plants compared with the fully oxidized pentavalent arsenate. The uptake of arsenite in plants has been shown to be mediated through a large subfamily of plant aquaglyceroporins, nodulin 26-like intrinsic proteins (NIPs). However, the efflux mechanisms, as well as the mechanism of arsenite-induced root growth inhibition, remain poorly understood. Using molecular physiology, synchrotron imaging, and root transport assay approaches, we show that the cellular transport of trivalent arsenicals in Arabidopsis thaliana is strongly modulated by PIN FORMED 2 (PIN2) auxin efflux transporter. Root transport assay using radioactive arsenite, X-ray fluorescence imaging (XFI) coupled with X-ray absorption spectroscopy (XAS), and inductively coupled plasma mass spectrometry analysis revealed that pin2 plants accumulate higher concentrations of arsenite in roots compared with the wild-type. At the cellular level, arsenite specifically targets intracellular sorting of PIN2 and thereby alters the cellular auxin homeostasis. Consistently, loss of PIN2 function results in arsenite hypersensitivity in roots. XFI coupled with XAS further revealed that loss of PIN2 function results in specific accumulation of arsenical species, but not the other metals such as iron, zinc, or calcium in the root tip. Collectively, these results suggest that PIN2 likely functions as an arsenite efflux transporter for the distribution of arsenical species in planta.
Assuntos
Proteínas de Arabidopsis/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arsenitos/toxicidade , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Reguladores de Crescimento de Plantas/metabolismoRESUMO
Over 200 million people worldwide are exposed to the human carcinogen, arsenic, in contaminated drinking water. In laboratory animals, arsenic and the essential trace element, selenium, can undergo mutual detoxification through the formation of the seleno-bis(S-glutathionyl) arsinium ion [(GS)2AsSe]-, which undergoes biliary and fecal elimination. [(GS)2AsSe]-, formed in animal red blood cells (RBCs), sequesters arsenic and selenium, and slows the distribution of both compounds to peripheral tissues susceptible to toxic effects. In human RBCs, the influence of arsenic on selenium accumulation, and vice versa, is largely unknown. The study aims were to characterize arsenite (AsIII) and selenite (SeIV) uptake by human RBCs, to determine if SeIV and AsIII increase the respective accumulation of the other in human RBCs, and ultimately to determine if this occurs through the formation and sequestration of [(GS)2AsSe]-. 75SeIV accumulation was temperature and Cl--dependent, inhibited by 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid (H2DIDS) (IC50 1 ± 0.2 µM), and approached saturation at 30 µM, suggesting uptake is mediated by the erythrocyte anion-exchanger 1 (AE1 or Band 3, gene SLC4A1). HEK293 cells overexpressing AE1 showed concentration-dependent 75SeIV uptake. 73AsIII uptake by human RBCs was temperature-dependent, partly reduced by aquaglyceroporin 3 inhibitors, and not saturated. AsIII increased 75SeIV accumulation (in the presence of albumin) and SeIV increased 73AsIII accumulation in human RBCs. Near-edge X-ray absorption spectroscopy revealed the formation of [(GS)2AsSe]- in human RBCs exposed to both AsIII and SeIV. The sequestration of [(GS)2AsSe]- in human RBCs potentially slows arsenic distribution to susceptible tissues and could reduce arsenic-induced disease.
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Arsenitos/sangue , Eritrócitos/metabolismo , Glutationa/sangue , Ácido Selenioso/sangue , Arsenitos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Células HEK293 , Humanos , Ácido Selenioso/farmacologia , Espectroscopia por Absorção de Raios X/métodosRESUMO
A new energy dispersive X-ray absorption spectroscopy (EDXAS) method is presented for simultaneous wide-field imaging and transmission X-ray absorption spectroscopy (XAS) to enable rapid imaging and speciation of elements. Based on spectral K-Edge Subtraction imaging (sKES), a bent Laue imaging system diffracting in the vertical plane was developed on a bend magnet beamline for selenium speciation. The high flux and small vertical focus, forming a wide horizontal line beam for projection imaging and computed tomography applications, is achieved by precise matching of lattice plane orientation and crystal surface (asymmetry angle). The condition generating a small vertical focus for imaging also provides good energy dispersion. Details for achieving sufficient energy and spatial resolution are demonstrated for both full field imaging and computed tomography in quantifying selenium chemical species. While this system has lower sensitivity as it uses transmission and may lack the flux and spatial resolution of a dedicated focused beamline system, it has significant potential in rapid screening of heterogeneous biomedical or environmental systems to correlate metal speciation with function.
RESUMO
BACKGROUND: Selenium is an essential element with a rich and varied chemistry in living organisms. It plays a variety of important roles ranging from being essential in enzymes that are critical for redox homeostasis to acting as a deterrent for herbivory in hyperaccumulating plants. Despite its importance there are many open questions, especially related to its chemistry in situ within living organisms. SCOPE OF REVIEW: This review discusses X-ray spectroscopy and imaging of selenium in biological samples, with an emphasis on the methods, and in particular the techniques of X-ray absorption spectroscopy (XAS) and X-ray fluorescence imaging (XFI). We discuss the experimental methods and capabilities of XAS and XFI, and review their advantages and their limitations. A perspective on future possibilities and next-generation of experiments is also provided. MAJOR CONCLUSIONS: XAS and XFI provide powerful probes of selenium chemistry, together with unique in situ capabilities. The opportunities and capabilities of the next generation of advanced X-ray spectroscopy experiments are particularly exciting. GENERAL SIGNIFICANCE: XAS and XFI provide versatile tools that are generally applicable to any element with a convenient X-ray absorption edge, suitable for investigating complex systems essentially without pre-treatment.
RESUMO
Arsenicosis, a syndrome caused by ingestion of arsenic contaminated drinking water, currently affects millions of people in South-East Asia and elsewhere. Previous animal studies revealed that the toxicity of arsenite essentially can be abolished if selenium is co-administered as selenite. Although subsequent studies have provided some insight into the biomolecular basis of this striking antagonism, many details of the biochemical pathways that ultimately result in the detoxification and excretion of arsenic using selenium supplements have yet to be thoroughly studied. To this end and in conjunction with the recent Phase III clinical trial "Selenium in the Treatment of Arsenic Toxicity and Cancers", we have applied synchrotron X-ray techniques to elucidate the mechanisms of this arsenic-selenium antagonism at the tissue and organ levels using an animal model. X-ray fluorescence imaging (XFI) of cryo-dried whole-body sections of laboratory hamsters that had been injected with arsenite, selenite, or both chemical species, provided insight into the distribution of both metalloids 30 minutes after treatment. Co-treated animals showed strong co-localization of arsenic and selenium in the liver, gall bladder and small intestine. X-ray absorption spectroscopy (XAS) of freshly frozen organs of co-treated animals revealed the presence in liver tissues of the seleno bis-(S-glutathionyl) arsinium ion, which was rapidly excreted via bile into the intestinal tract. These results firmly support the previously postulated hepatobiliary excretion of the seleno bis-(S-glutathionyl) arsinium ion by providing the first data pertaining to organs of whole animals.
Assuntos
Intoxicação por Arsênico/metabolismo , Arsênio/metabolismo , Mamíferos/metabolismo , Selênio/metabolismo , Animais , Arsênio/farmacocinética , Intoxicação por Arsênico/diagnóstico , Feminino , Mesocricetus , Especificidade de Órgãos , Selênio/farmacocinética , Espectrometria por Raios X/métodos , Síncrotrons , Distribuição Tecidual , Espectroscopia por Absorção de Raios XRESUMO
Certain arsenic and selenium compounds show a remarkable mutual cancelation of toxicities, where a lethal dose of one can be voided by an equimolar and otherwise lethal dose of the other. It is now well established that the molecular basis of this antagonism is the formation and biliary excretion of seleno bis-(S-glutathionyl) arsinium anion [(GS)2AsSe](-). Previous work has definitively demonstrated the presence of [(GS)2AsSe](-) in rabbit bile, but only in the presence of other arsenic and selenium species. Rabbits have a gall bladder, which concentrates bile and lowers its pH; it seems likely that this may be responsible for the breakdown of biliary [(GS)2AsSe](-). Since rats have no gall bladder, the bile proceeds directly through the bile duct from the hepatobiliary tree. In the present work we have shown that the primary product of biliary co-excretion of arsenic and selenium in rats is [(GS)2AsSe](-), with essentially 100% of the arsenic and selenium present as this species. The chemical plausibility of the X-ray absorption spectroscopy-derived structural conclusions of this novel arsenic and selenium co-excretion product is supported by density functional theory calculations. These results establish the biomolecular basis to further explore the use of selenium dietary supplements as a possible palliative for chronic low-level arsenic poisoning of human populations.
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Ânions/metabolismo , Arsênio/metabolismo , Bile/metabolismo , Compostos de Selênio/metabolismo , Animais , Arsênio/química , Antagonismo de Drogas , Masculino , Estrutura Molecular , Coelhos , Ratos , Ratos Wistar , Compostos de Selênio/química , Espectroscopia por Absorção de Raios XRESUMO
Clioquinol (5-chloro-7-iodo-8-hydroxyquinoline) recently has shown promising results in the treatment of Alzheimer's disease and in cancer therapy, both of which also are thought to be due to clioquinol's ability as a lipophilic copper chelator. Previously, clioquinol was used as an anti-fungal and anti-protozoal drug that was responsible for an epidemic of subacute myelo-optic neuropathy (SMON) in Japan during the 1960s, probably a myeloneuropathy arising from a clioquinol-induced copper deficiency. Previous X-ray absorption spectroscopy of solutions of copper chelates of clioquinol suggested unusual coordination chemistry. Here we use a combination of electron paramagnetic, UV-visible and X-ray absorption spectroscopies to provide clarification of the chelation chemistry between clioquinol and copper. We find that the solution structures for the copper complexes formed with stoichiometric and excess clioquinol are conventional 8-hydroxyquinolate chelates. Thus, the promise of clioquinol in new treatments for Alzheimer's disease and in cancer therapy is not likely to be due to any novel chelation chemistry, but rather due to other factors including the high lipophilicity of the free ligand and chelate complexes.