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1.
Sci Total Environ ; 955: 176877, 2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39406271

RESUMO

A full-scale passive treatment plant using barium carbonate (BaCO3), the mineral witherite, as a Dispersed Alkaline Substrate (DAS) for strongly contaminated acid mine drainage was implemented for the first time globally at Mina Concepción, located in the Iberian Pyrite Belt (SW Spain). The plant was monitored over a 105-day period, covering the wettest months of the hydrological year and with a mean flow around 4 L s-1. The AMD treated in the plant exhibits a high strength, with an average sulfate concentration around 1500 mg L-1 and net acidity close to 1000 mg L-1 as CaCO3 equivalent. According to the above, the loading rate for SO4 and Fe was around 400 and 80 kg day-1, respectively. The treatment process produced an alkaline effluent with low metal content. Nearly complete removal of most metal(loid)s was achieved, with significant sulfate decrease to below 500 mg L-1 in the alkaline outflow of the barium carbonate tank. Barium carbonate demonstrated superior performance compared to magnesia, particularly in enhancing alkalinity and lowering net acidity and concentrations of sulfate and manganese. The high efficiency attained by the plant after the barium carbonate treatment is evidenced by compliance with environmental water quality standards for most contaminants.

2.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-39313025

RESUMO

OBJECTIVE: To evaluate the effect of endoscopic surgery on sexual function in patients with upper urinary tract (UUT) lithiasis. MATERIAL AND METHODS: We conducted an observational, prospective, longitudinal study with a single cohort of cases undergoing ureteroscopy (URS), retrograde intrarenal surgery (RIRS), or endoscopic combined intrarenal surgery (ECIRS). Patients' sexual response was assessed with questionnaires in the 30 days prior to surgery, and at one and three months after surgery. The International Index of Erectile Function (IIEF-t) was used in male patients, and the Female Sexual Function Index (FSFI) was used in female patients. RESULTS: Seventy patients - 34 men and 36 women - completed the study. Among men, the IIEF-t did not show significant difference between baseline scores (64.1 ±â€¯7.50) and those obtained at 3 months (63.8 ±â€¯9.51), with a non-significant decrease (p = 0.054) at the first month (61.4 ±â€¯10.4). Subdomains did not worsen at 3 months, and desire (IIEF-SD) improved from 7.3 ±â€¯1.9 to 8.0 ±â€¯1.8. Among women, the FSFI-t did not change significantly after surgery: baseline score (27.3 ±â€¯4.1), 1-month score (26.8 ±â€¯3.7) and 3-month score (27.5 ±â€¯4.2). No subdomain worsened at the third month. CONCLUSION: Endoscopic surgery for UUT is a safe technique in both sexes with no negative effect on sexual function. There are no differences between the baseline IIEF-t and FSFI-t scores and those obtained at 3 months.

3.
J Nematol ; 56(1): 20240030, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39157452

RESUMO

Mexico is the 8th largest producer of tomatoes. Meloidogyne enterolobii is reported in Sinaloa, affecting tomato cultivars with genetic resistance to Meloidogyne spp. We aimed to evaluate field applications of fluopyram, fluensulfone, and fluazaindolizine treatments for managing M. enterolobii on tomatoes. Experiments were set on raised beds in a shade house. Nematicides were applied via drip irrigation. Under fluopyram treatment, M. enterolobii did not reduce the number of extra-large-size fruits. The number of large-size fruits with fluopyram and fluazaindolizine plus fluopyram treatments was also unaffected by M. enterolobii. Yield from the treatments fluopyram, fluazaindolizine plus fluopyram, and fluensulfone plus fluopyram was similar to the control treatment without M. enterolobii. Finally, fluazaindolizine plus fluopyram, fluopyram, and fluensulfone plus fluopyram treatments showed the highest reduction of root galling. We conclude that the fluopyram was more effective as an individual treatment. Pre-plant applications of fluensulfone and fluazaindolizine reduced the damage to the plant and the loss of yield; however, the complementary application of fluorinated nematicides improved the management of M. enterolobii in the tomato crop.

4.
Rev Clin Esp (Barc) ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39214340

RESUMO

INTRODUCTION: We analysed the frequency of atrial fibrillation (AF) delayed diagnosis and the factors associated with it in newly diagnosed patients. METHODS: This was a descriptive, cross-sectional, multicentre study. Data were collected from newly diagnosed patients with AF through medical records review and interviews during cardiology, internal medicine, primary care and emergency department consultations in Spain. RESULTS: A total of 201 physicians participated in the study (64.2% cardiologists, 21.4% internists). 948 patients (58% men; mean age 72.8 years) were included. In 41.8% of patients, AF was classified as paroxysmal at diagnosis, 30.9% as persistent and 27.3% as permanent. The diagnosis was coincidental in 37%. It was considered that a delayed diagnosis occurred in 49.3% of patients. This delay was associated with the presence of permanent or persistent AF, older age or valvular disease. 74.8% of patients had some contact with the healthcare system in the preceding year. The diagnosis could have been established between 1 and 6 months earlier in 50.7% of cases and more than six months earlier in 20.1%. 54.4% of the patients had experienced AF compatible symptomatology previously. Of these, 32.6% had a consultation without a diagnosis. CONCLUSIONS: In a significant proportion of AF cases, there is a diagnostic delay. Many people with compatible symptoms neither seek consultations nor contact the healthcare system facilities. Consequently, the opportunity for early diagnosis is lost.

5.
Toxicon ; 249: 108036, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39059561

RESUMO

Mexico has the highest diversity of snake species in the world, following Australia when considering just venomous snakes. Specifically, in Sonora, the second largest state in the country, more than 15 highly venomous species occur, including the northern black-tailed rattlesnake (Crotalus molossus). This specie's venom has not been as thoroughly researched in contrast with other Mexican vipers, nevertheless some studies report its biological activity and even pharmacological potential with antibacterial and cytotoxic activity. In this study we identified the main protein components from a pool of C. molossus venom through a gel-free proteomics approach, reporting ∼140 proteins belonging to the SVMP (38.76%), PLA2 (28.75%), CTL (11.93%), SVSP (6.03%) and LAAO (5.67%) toxin families. To study its biological activities, we evaluated its hemolytic, antibacterial, and cytotoxic activity in red blood cells, Gram positive and negative bacteria and a luminal A breast carcinoma cell line (T47D), respectively, in vitro. We report that concentrations <100 µg/mL are potentially not hemolytic and reduced the bacteria viability of E. coli and S. aureus with an IC50 of 10.27 and 11.51 µg/mL, respectively. Finally, we determined the C. molossus venom as cytotoxic against the T47D breast carcinoma cell line, with an IC50 of 1.55 µg/mL. We suggest that the evaluated cytotoxicity was due to a high abundance of SVMPs and PLA2s, since it's been reported that they affect the extracellular matrix and membrane permeation. This may provide a useful tool for pharmaceutical screening in the future.


Assuntos
Antibacterianos , Venenos de Crotalídeos , Crotalus , Escherichia coli , Staphylococcus aureus , Animais , Venenos de Crotalídeos/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Hemólise/efeitos dos fármacos , Feminino , Testes de Sensibilidade Microbiana , Eritrócitos/efeitos dos fármacos , Serpentes Peçonhentas
7.
Sci Rep ; 14(1): 17192, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060474

RESUMO

The ability to distinguish multiple forms of plutonium from one another, such as oxide and metal, is paramount in areas of nuclear nonproliferation and international safeguards. In its metal form, plutonium can be readily used in a nuclear weapon, while oxide forms are associated with nuclear reactor fuel. Oxide-based plutonium forms emit neutrons with an energy spectrum that is significantly different from the fission neutrons that are emitted from plutonium metal. Organic scintillation detectors output pulses that are proportional to the neutron energy deposited, and therefore present a means of distinguishing these plutonium forms based on their energy spectra. In this work, metal and oxide forms of plutonium were measured using a handheld detection system based on an organic glass scintillator. Monte Carlo modeling of these experiments was performed to provide insight into the origin of the features in the observed light output spectra. Through analysis of multiple regions of these spectra, in a matter of minutes we were able to unambiguously discriminate oxide and metal plutonium forms from one another and from a plutonium-beryllium neutron source, which was considered for comparison because these sources are commonly used in industrial applications. The ability to discriminate weapons-usable material from nuclear reactor fuel has applications in nuclear treaty verification and safeguards.

8.
Surg Radiol Anat ; 46(8): 1219-1230, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38888835

RESUMO

PURPOSE: The literature has for too long described the arterial supply of the mandible as coming from a single artery, the inferior alveolar artery, and being of the terminal type. Rather, it appears to come from an extensive and complex arterial network dependent on the lingual, facial, and maxillary arteries and their collateral branches. Our study aims to confirm and demonstrate the arterial vascular richness of the mandible and to establish arterial mapping. METHODS: The arterial vascularization of the mandible was revealed in six anatomic specimens after performing selective injections of the lingual, facial, and maxillary arteries with different dyes. A specimen was injected intra-arterially with colored latex at the level of the maxillary artery for a morphometric study. RESULTS: Eighteen selective arterial injections were performed on six anatomic specimens. The mucocutaneous, musculoperiosteal, and intramedullary vascularizations were analyzed. Each of the arteries has a defined and delimited cutaneo-mucous vascular territory. The facial and maxillary arteries supply the musculoperiosteal vascularization of the mandible from the condyle to the symphysis. The lingual artery supplies only the inner cortex of the parasymphyseal and symphyseal regions. The facial and maxillary arteries provide intramedullary vascularization from the angle of the mandible to the parasymphysis. The vascularization of the symphysis depends on the facial artery. No staining was found in the condyle region. Neoprene latex injection was performed on an anatomic specimen, revealing a permeable anastomosis between the inferior alveolar and facial arteries. CONCLUSION: The arterial vascularization of the mandible is dependent on the maxillary, facial, and lingual arteries. This is a network vasculature. This study makes it possible to establish an arterial map of the mandible. The presence of an anastomosis between the inferior alveolar artery and the facial artery confirms the existence of dynamic and borrowed vascularization. Knowledge of this arterial system makes it possible to adapt maxillofacial surgical care and to anticipate possible intraoperative complications.


Assuntos
Artérias , Mandíbula , Humanos , Mandíbula/irrigação sanguínea , Mandíbula/anatomia & histologia , Artérias/anatomia & histologia , Cadáver , Masculino , Feminino , Artéria Maxilar/anatomia & histologia
10.
Actas Urol Esp (Engl Ed) ; 48(7): 538-544, 2024 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38599570

RESUMO

OBJECTIVE: This study aimed to assess the influence of age, period, and cohort (A-P-C) factors on kidney cancer (KC) incidence trends in Spain from 1990 to 2019. METHODS: Employing data from the Global Burden of Disease Study 2019, we employed joinpoint analysis to determine long-term patterns and A-P-C modelling to quantify net drift, local drift, longitudinal age curves, and rate ratios (RRs) of period and cohort effects. RESULTS: Over the period 1990-2019, an estimated 142,811 cases of KC were diagnosed in Spain. A consistent upward trend in KC incidence was observed for both men and women, with the male-to-female ratio remaining stable at 2.6. Joinpoint analysis identified three distinct periods for men: An initial period (1990-1995) characterised by a significant increase in rates, a subsequent period (1995-2016) characterised by a slowdown in the rate of increase, and a final period (2016-2019) in which rates have plateaued. In women, 2 time periods were observed: an initial period (1990-2007) in which rates increased significantly, followed by a period of stabilization (2007-2019). Men born in the early-mid 20th century had a rising KC risk, peaking in the 1960s. Women's risk rose steadily, peaking in the late 1990s. CONCLUSION: A-P-C analysis reveals steady KC incidence increase in both genders over three decades. This highlights the need for targeted public health policies and effective prevention strategies.


Assuntos
Carga Global da Doença , Neoplasias Renais , Humanos , Espanha/epidemiologia , Incidência , Masculino , Neoplasias Renais/epidemiologia , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Fatores de Tempo , Fatores Etários , Distribuição por Idade , Idoso de 80 Anos ou mais , Estudos de Coortes
11.
Breast Cancer Res Treat ; 206(2): 317-328, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38561577

RESUMO

PURPOSE: To evaluate the efficacy and safety of first-line therapy with palbociclib in a Spanish cohort treated after palbociclib approval. METHODS: PALBOSPAIN is an observational, retrospective, multicenter study evaluating real-world patterns and outcomes with 1 L palbociclib in men and women (any menopausal status) with advanced HR+/HER2- BC diagnosed between November 2017 and November 2019. The primary endpoint was real-world progression-free survival (rw-PFS). Secondary endpoints included overall survival (OS), the real-world response rate (rw-RR), the clinical benefit rate, palbociclib dose reduction, and safety. RESULTS: A total of 762 patients were included. The median rw-PFS and OS were 24 months (95% CI 21-27) and 42 months (40-not estimable [NE]) in the whole population, respectively. By cohort, the median rw-PFS and OS were as follows: 28 (95% CI 23-39) and 44 (95% CI 38-NE) months in patients with de novo metastatic disease, 13 (95% CI 11-17) and 36 months (95% CI 31-41) in patients who experienced relapse < 12 months after the end of ET, and 31 months (95% CI 26-37) and not reached (NR) in patients who experienced relapse > 12 months after the end of ET. rw-PFS and OS were longer in patients with oligometastasis and only one metastatic site and those with non-visceral disease. The most frequent hematologic toxicity was neutropenia (72%; grade ≥ 3: 52.5%), and the most common non-hematologic adverse event was asthenia (38%). CONCLUSION: These findings, consistent with those from clinical trials, support use of palbociclib plus ET as 1 L for advanced BC in the real-world setting, including pre-menopausal women and men. TRIAL REGISTRATION NUMBER: NCT04874025 (PALBOSPAIN). Date of registration: 04/30/2021 retrospectively registered.


Assuntos
Neoplasias da Mama , Piperazinas , Piridinas , Receptor ErbB-2 , Humanos , Piridinas/uso terapêutico , Piridinas/efeitos adversos , Piridinas/administração & dosagem , Feminino , Piperazinas/uso terapêutico , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Pessoa de Meia-Idade , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/metabolismo , Idoso , Adulto , Masculino , Estudos Retrospectivos , Receptor ErbB-2/metabolismo , Idoso de 80 Anos ou mais , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/administração & dosagem , Intervalo Livre de Progressão
13.
Hernia ; 28(4): 1103-1112, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38478185

RESUMO

BACKGROUND: The aim of this multicentre study was to analyse the outcomes of biosynthetic absorbable poly-4-hydroxybutyrate (P4HB) prosthesis implantation in patients undergoing ventral hernia repair (VHR) in the context of different degrees of contamination. METHODS: From May 2016 to December 2021, a multicentre retrospective analysis of patients who underwent elective or urgent hernia repair with P4HB prosthesis was performed in seven hospitals in Spain and Portugal. Patients with a postoperative follow-up of less than 20 months and those within the theoretical period of prosthesis resorption were excluded from the study. Regarding the degree of contamination, patients were assessed according to the modified Ventral Hernia Working Group (VHWG) classification. Epidemiological data, hernia characteristics, surgical and postoperative variables (Clavien-Dindo classification) of these patients were analyzed. Risk factors related to long-term recurrence were studied by a multivariate analysis. RESULTS: In 236 cases of P4HB prosthesis implantation, repair in cases of Grade 3 was the most frequent (49.1%), followed by Grade 2 in 42.3% of cases and Grade 1 in 8.4%. The most frequent complications were Grade 1, with the majority occurring during the first year. The overall rate of surgical site occurrences (SSO) was 30%. The hernia recurrence rate was 14.4% (n = 34), with a mean postoperative follow-up time of 41 months (22-61). The multivariate analysis showed that the onlay location of the mesh (OR 1.07; CI 1.42-2.70, p = 0.004) was a significant independent risk factor for recurrence. CONCLUSIONS: The use of a P4HB bioresorbable mesh for the VHR with different degrees of contamination leads to favourable results overall, with an acceptable rate of hernia recurrence. The onlay location of the P4HB prosthesis is the main factor in recurrence in both elective and emergency settings.


Assuntos
Implantes Absorvíveis , Hérnia Ventral , Herniorrafia , Telas Cirúrgicas , Humanos , Hérnia Ventral/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Herniorrafia/métodos , Herniorrafia/efeitos adversos , Pessoa de Meia-Idade , Idoso , Recidiva , Hidroxibutiratos , Poliésteres , Complicações Pós-Operatórias/epidemiologia , Adulto
14.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(4): 282-290, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408610

RESUMO

OBJECTIVE: To improve knowledge about routine clinical practice in the management of paediatric acute pain in Spain. METHODS: A telematic survey was conducted via the Internet on a representative sample of healthcare professionals involved in the management of paediatric acute pain (specifically anaesthesiologists) in Spain. The survey included 28 questions about their usual clinical practice in the assessment and treatment of acute pain, and also training and organisational aspects in paediatric acute pain. RESULTS: The survey was completed during March 2021 by 150 specialists in anaesthesiology. The respondents widely experienced in the management of acute paediatric pain (mean years of experience: 14.3: SD: 7.8), essentially in acute postoperative pain (97% of cases). Although 80% routinely used validated paediatric acute pain assessment scales, only 2.6% used specific scales adapted for patients with cognitive impairment. Most of the respondents routinely used analgesic drugs such as paracetamol (99%) or metamizole (92%), but only 84% complemented these drugs with a loco-regional blocking technique or other non-steroidal anti-inflammatory drugs (62%). Furthermore, only 62.7% acknowledged having received specific training in paediatric acute pain, only 45% followed hospital institutional protocols, and a scant 28% did so through paediatric pain units. CONCLUSIONS: The survey identified important points for improvement in the training and organisation of acute pain management in Spanish paediatric patients.


Assuntos
Dor Aguda , Pesquisas sobre Atenção à Saúde , Manejo da Dor , Espanha , Humanos , Dor Aguda/tratamento farmacológico , Dor Aguda/terapia , Manejo da Dor/métodos , Criança , Padrões de Prática Médica/estatística & dados numéricos , Pediatria , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/terapia , Analgésicos/uso terapêutico , Medição da Dor/estatística & dados numéricos , Anestesiologia/educação , Anestesiologistas/estatística & dados numéricos
16.
Comput Methods Programs Biomed ; 245: 108033, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278030

RESUMO

BACKGROUND AND OBJECTIVE: In the last years, the Emergency Department (ED) has become an important source of admissions for hospitals. Since late 90s, the number of ED visits has been steadily increasing, and since Covid19 pandemic this trend has been much stronger. Accurate prediction of ED visits, even for moderate forecasting time-horizons, can definitively improve operational efficiency, quality of care, and patient outcomes in hospitals. METHODS: In this paper we propose two different interpretable approaches, based on Machine Learning algorithms, to accurately forecast hospital emergency visits. The proposed approaches involve a first step of data segmentation based on two different criteria, depending on the approach considered: first, a threshold-based strategy is adopted, where data is divided depending on the value of specific predictor variables. In a second approach, a cluster-based ensemble learning is proposed, in such a way that a clustering algorithm is applied to the training dataset, and ML models are then trained for each cluster. RESULTS: The two proposed methodologies have been evaluated in real data from two hospital ED visits datasets in Spain. We have shown that the proposed approaches are able to obtain accurate ED visits forecasting, in short-term and also long-term prediction time-horizons up to one week, improving the efficiency of alternative prediction methods for this problem. CONCLUSIONS: The proposed forecasting approaches have a strong emphasis on providing explainability to the problem. An analysis on which variables govern the problem and are pivotal for obtaining accurate predictions is finally carried out and included in the discussion of the paper.


Assuntos
Visitas ao Pronto Socorro , Serviço Hospitalar de Emergência , Humanos , Hospitais , Algoritmos , Aprendizado de Máquina
17.
Nature ; 627(8003): 281-285, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286342

RESUMO

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-µas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems.

18.
Rev Esp Cir Ortop Traumatol ; 68(1): 26-34, 2024.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37270057

RESUMO

INTRODUCTION AND OBJECTIVES: Modular neck primary stems were introduced with the theoretical advantage of restoring the hip anatomy more precisely. However, the presence of a second junction has been associated with increased corrosion and release of metal debris. The objective of our study is to quantify of chromium and cobalt serum values, and to analyze their temporal evolution during five years. MATERIAL AND METHODS: We present a prospective series of 61 patients who underwent primary total hip arthroplasty by implantation of the HMAX-M® stem (Limacorporate, San Daniele, Italy). Serum chromium and cobalt determinations were performed at six months, two years and five years. RESULTS: Our series shows a progressive elevation in chromium levels with a significant difference between chromium values at six months (0.35±0.18) and five years (0.52±0.36), P=.01. Regarding cobalt, a statistically significant elevation is observed between six months and two years and a subsequent stabilization of values between two and five years, with a cobalt mean at six months (1.17±0.8) significantly lower than at two (2.63±1.76) and five years (2.84±2.1), P=.001. CONCLUSION: Elevated serum cobalt levels have been observed in patients who underwent modular neck stem implantation. The results obtained in this study have limited the use of stems with a modular neck in our clinical practice.

19.
Rev Esp Cir Ortop Traumatol ; 68(1): T26-T34, 2024.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37992863

RESUMO

INTRODUCTION AND OBJECTIVES: Modular neck primary stems were introduced with the theoretical advantage of restoring the hip anatomy more precisely. However, the presence of a second junction has been associated with increased corrosion and release of metal debris. The objective of our study is to quantify of chromium and cobalt serum values, and to analyse their temporal evolution during five years. MATERIAL AND METHODS: We present a prospective series of 61 patients who underwent primary total hip arthroplasty by implantation of the H MAX-M® stem (Limacorporate, San Daniele, Italy). Serum chromium and cobalt determinations were performed at six months, two years and five years. RESULTS: Our series shows a progressive elevation in chromium levels with a significant difference between chromium values at six months (0.35±0.18) and five years (0.52±0.36), p=.01. Regarding cobalt, a statistically significant elevation is observed between six months and two years and a subsequent stabilisation of values between two and five years, with a cobalt mean at six months (1.17±0.8) significantly lower than at two (2.63±1.76) and five years (2.84±2.1), p=.001. CONCLUSION: Elevated serum cobalt levels have been observed in patients who underwent modular neck stem implantation. The results obtained in this study have limited the use of stems with a modular neck in our clinical practice.

20.
Phys Chem Chem Phys ; 26(2): 830-841, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38099823

RESUMO

We present an extensive investigation using density functional theory (DFT) calculations on various model graphene oxide (GO) nanostructures interacting with chlorine monoxide ClO, aiming to understand the role of this highly oxidizing species in C-C bond breakage and the formation of significant holes on GO sheets. During its function, the myeloperoxidase (MPO) enzyme abundantly generates chlorine-oxygen-containing species and their presence has been identified as the cause of degradation in carbon nanotubes of diverse sizes, morphologies, and chemical compositions, both in in vivo and in vitro samples. Notably, Kurapati et al. (Small, 2015, 11, 3985-3994) demonstrated efficient degradation of single GO monolayers through MPO catalysis, though the exact degradation mechanism remains unclear. In our study, we discover that breaking C-C bonds in a single graphene oxide sheet is achievable through a simple mechanism involving the dissociation of two ClO molecules that are chemically attached as nearest neighbor species but bonded to opposite sides of the GO layer (up/down configuration). Two new carbonyl oxygens appear on the surface and the Cl atoms can be transferred to the carbon layer or as physisorbed species near the GO surface. Relatively small energy barriers are associated with these molecular events. Continuing this process on neighboring sites leads to the presence of larger holes on the GO surface, accompanied by an increase in carbonyl species on the carbon network, consistent with X-ray photoelectron spectroscopy measurements. Indeed, the distribution of oxygen functionalities is found to be crucial in defining the damage pattern induced in the carbon layer. We emphasize the important role played by the local charge distribution in the stability or instability of chemical bonds, as well as in the energy barriers and reaction pathways. Finally, we explore the possibility of achieving chlorination of GO following MPO exposure. The here-reported predictions could be the root cause of the experimentally observed low stability of individual GO sheets during the MPO catalytic cycle.

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