All that glitters is not gold: X-ray fluorescence analysis of a fixed dental prosthesis from Colecção de Esqueletos Identificados Século XXI, Portugal (CEI/XXI).

Access to better health care anticipates that more medical devices can be found alongside skeletal remains. Those employed in oral rehabilitation, with available brands or batch/series, can prove useful in the identification process. A previous study in the Colecção de Esqueletos Identificados Século XXI described macroscopically the dental prostheses. An unusual case of a dental device with chromatic alterations demonstrated to require a more detailed analysis. The individual, a 53-year-old male, exhibited, at both arches, a fixed tooth-supported rehabilitation, with gold colouring classified initially as a gold-palladium alloy. Simultaneously, a green pigmentation deposit was observable in bone and prosthesis. This investigation aimed to verify the elemental composition of the dental prosthesis alloy. Elemental analysis was performed by X-ray fluorescence in two regions (labial surface of the prosthetic crown and the root surface of the lower right lateral incisor). Both the spectra and the qualitative results found higher levels of copper and aluminium, followed by nickel, iron, zinc, and manganese. No gold or palladium was detected. The most probable assumption is that a copper-aluminium alloy was used, as its elemental concentration corresponds to those measured in similar devices. Dental prostheses of copper-aluminium alloys have been made popular since the 1980s, particularly in the USA, Japan, and Eastern Europe. Apart from the biographical information, it was also known that the individual's place of birth was an Eastern European country, which highlighted the usefulness of this type of information when dealing with missing people cases.

Upregulation of APP endocytosis by neuronal aging drives amyloid-dependent synapse loss.

Neuronal aging increases the risk of late-onset Alzheimer's disease. During normal aging, synapses decline, and ß-amyloid (Aß) accumulates intraneuronally. However, little is known about the underlying cell biological mechanisms. We studied neuronal aging using normal-aged brain and aged mouse primary neurons that accumulate lysosomal lipofuscin and show synapse loss. We identified the upregulation of amyloid precursor protein (APP) endocytosis as a neuronal aging mechanism that potentiates APP processing and Aß production in vitro and in vivo. The increased APP endocytosis may contribute to the early endosome enlargement observed in the aged brain. Mechanistically, we showed that clathrin-dependent APP endocytosis requires F-actin and that clathrin and endocytic F-actin increase with neuronal aging. Finally, Aß production inhibition reverts synaptic decline in aged neurons, whereas Aß accumulation, promoted by endocytosis upregulation in younger neurons, recapitulates aging-related synapse decline. Overall, we identify APP endocytosis upregulation as a potential mechanism of neuronal aging and, thus, a novel target to prevent late-onset Alzheimer's disease. This article has an associated First Person interview with the first author of the paper.

Ultrasound Assessment in a Pregnant Woman? Not just for the Fetus.

Pericarditis is a relatively common diagnosis worldwide; however, there are few data published on the frequency, diagnosis, and management of pericardial diseases in pregnant women. Ultrasonography has established its utmost importance and is worldwide recognized in pregnancy and fetal evaluation. Moreover, point-of-care ultrasonography of pregnant women, guided by clinical examination and history, can play an equally fundamental role. We present a case of a 37-year-old pregnant woman who presented at the emergency department with pleuritic chest pain, fever, and cough. Bedside point-of-care ultrasonography confirmed pericarditis revealing an organized pericardial effusion, leading to patient hospitalization and initiation of therapy. The importance and acknowledgment of portable and hand-held ultrasonography devices are growing since it enables physicians not only to make a fast and accurate diagnosis but also to access evolution in inpatient and outpatient settings.

Production of high-quality SARS-CoV-2 antigens: Impact of bioprocess and storage on glycosylation, biophysical attributes, and ELISA serologic tests performance.

Serological assays are valuable tools to study SARS-CoV-2 spread and, importantly, to identify individuals that were already infected and would be potentially immune to a virus reinfection. SARS-CoV-2 Spike protein and its receptor binding domain (RBD) are the antigens with higher potential to develop SARS-CoV-2 serological assays. Moreover, structural studies of these antigens are key to understand the molecular basis for Spike interaction with angiotensin converting enzyme 2 receptor, hopefully enabling the development of COVID-19 therapeutics. Thus, it is urgent that significant amounts of this protein became available at the highest quality. In this study, we produced Spike and RBD in two human derived cell hosts: HEK293-E6 and Expi293F™. We evaluated the impact of different and scalable bioprocessing approaches on Spike and RBD production yields and, more importantly, on these antigens' quality attributes. Using negative and positive sera collected from human donors, we show an excellent performance of the produced antigens, assessed in serologic enzyme-linked immunosorbent assay (ELISA) tests, as denoted by the high specificity and sensitivity of the test. We show robust Spike productions with final yields of approx. 2 mg/L of culture that were maintained independently of the production scale or cell culture strategy. To the best of our knowledge, the final yield of 90 mg/L of culture obtained for RBD production, was the highest reported to date. An in-depth characterization of SARS-CoV-2 Spike and RBD proteins was performed, namely the antigen's oligomeric state, glycosylation profiles, and thermal stability during storage. The correlation of these quality attributes with ELISA performance show equivalent reactivity to SARS-CoV-2 positive serum, for all Spike and RBD produced, and for all storage conditions tested. Overall, we provide straightforward protocols to produce high-quality SARS-CoV-2 Spike and RBD antigens, that can be easily adapted to both academic and industrial settings; and integrate, for the first time, studies on the impact of bioprocess with an in-depth characterization of these proteins, correlating antigen's glycosylation and biophysical attributes to performance of COVID-19 serologic tests.

Determinants of the Use of Health and Fitness Mobile Apps by Patients With Asthma: Secondary Analysis of Observational Studies.

BACKGROUND: Health and fitness apps have potential benefits to improve self-management and disease control among patients with asthma. However, inconsistent use rates have been reported across studies, regions, and health systems. A better understanding of the characteristics of users and nonusers is critical to design solutions that are effectively integrated in patients' daily lives, and to ensure that these equitably reach out to different groups of patients, thus improving rather than entrenching health inequities. OBJECTIVE: This study aimed to evaluate the use of general health and fitness apps by patients with asthma and to identify determinants of usage. METHODS: A secondary analysis of the INSPIRERS observational studies was conducted using data from face-to-face visits. Patients with a diagnosis of asthma were included between November 2017 and August 2020. Individual-level data were collected, including age, gender, marital status, educational level, health status, presence of anxiety and depression, postcode, socioeconomic level, digital literacy, use of health services, and use of health and fitness apps. Multivariate logistic regression was used to model the probability of being a health and fitness app user. Statistical analysis was performed in R. RESULTS: A total of 526 patients attended a face-to-face visit in the 49 recruiting centers and 514 had complete data. Most participants were ≤40 years old (66.4%), had at least 10 years of education (57.4%), and were in the 3 higher quintiles of the socioeconomic deprivation index (70.1%). The majority reported an overall good health status (visual analogue scale [VAS] score>70 in 93.1%) and the prevalence of anxiety and depression was 34.3% and 11.9%, respectively. The proportion of participants who reported using health and fitness mobile apps was 41.1% (n=211). Multivariate models revealed that single individuals and those with more than 10 years of education are more likely to use health and fitness mobile apps (adjusted odds ratio [aOR] 2.22, 95%CI 1.05-4.75 and aOR 1.95, 95%CI 1.12-3.45, respectively). Higher digital literacy scores were also associated with higher odds of being a user of health and fitness apps, with participants in the second, third, and fourth quartiles reporting aORs of 6.74 (95%CI 2.90-17.40), 10.30 (95%CI 4.28-27.56), and 11.52 (95%CI 4.78-30.87), respectively. Participants with depression symptoms had lower odds of using health and fitness apps (aOR 0.32, 95%CI 0.12-0.83). CONCLUSIONS: A better understanding of the barriers and enhancers of app use among patients with lower education, lower digital literacy, or depressive symptoms is key to design tailored interventions to ensure a sustained and equitable use of these technologies. Future studies should also assess users' general health-seeking behavior and their interest and concerns specifically about digital tools. These factors may impact both initial engagement and sustained use.

Mathematical Models to Measure the Variability of Nodes and Networks in Team Sports.

Pattern analysis is a widely researched topic in team sports performance analysis, using information theory as a conceptual framework. Bayesian methods are also used in this research field, but the association between these two is being developed. The aim of this paper is to present new mathematical concepts that are based on information and probability theory and can be applied to network analysis in Team Sports. These results are based on the transition matrices of the Markov chain, associated with the adjacency matrices of a network with n nodes and allowing for a more robust analysis of the variability of interactions in team sports. The proposed models refer to individual and collective rates and indexes of total variability between players and teams as well as the overall passing capacity of a network, all of which are demonstrated in the UEFA 2020/2021 Champions League Final.

Effects of strengthening the surae triceps muscle on venous pump function in chronic venous insufficiency.

BACKGROUND: Chronic venous insufficiency (CVI) is a common disease that causes calf muscle pump dysfunction and has repercussions for the hemodynamics of the structures involved. OBJECTIVES: To analyze the effects on venous hemodynamics of exercises to strengthen the calf muscles in patients with CVI. METHODS: The study analyzed 25 lower limbs with CVI, classified from C1 to C5 according to the Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) classification, in 13 patients recruited from a Lymphedema and Angiodysplasia Clinic at the Hospital Universitário Regional dos Campos Gerais (Brazil). The variables analyzed were collected by isometric dynamometry, goniometry, leg circumference measurement, and adipometry at baseline, after 1 month and 2 months and at the end of the exercise protocol. RESULTS: Dorsiflexion and plantar flexion measurements increased by 5º (p < 0.001). Adipometry detected a reduction in 5 mm (p < 0.001). When grouped by CEAP class, C2 exhibited 5º increases in dorsiflexion (p = 0.02) and plantar flexion (p < 0.001); C3 exhibited a 5ºincrease in dorsiflexion (p = 0.003) and a 1mm reduction in adipometry (p < 0.004); and C1 exhibited a 1.2cm increase in leg circumference (p = 0.04). CONCLUSIONS: Administration of exercise protocols should be considered as a treatment option for CVI, since it has a positive impact on risk factors and on the functions that are impaired by this pathology.

Human Factor Considerations in Using Personal Protective Equipment in the COVID-19 Pandemic Context: Binational Survey Study.

BACKGROUND: Full level 1 personal protective equipment (PPE) is used in various domains and contexts. Prior research has shown influences of such equipment on performance, comfort, and contamination levels. The coronavirus disease (COVID-19) pandemic forced a pervasive requirement of PPE, with little preparation, rushed deployment, inadequate time for training, and massive use by personnel who are inexperienced or not qualified in its effective use. OBJECTIVE: This study aims to examine the key human factors (physical and ergonomic, perceptual and cognitive) that influence the use of level 1 PPE when attending to patients with suspected or confirmed COVID-19. METHODS: The research approach consisted of a short survey disseminated to health care professionals in two countries, Israel and Portugal, with similar demographics and health care systems. The survey included 10 items with a 5-point Likert scale regarding the key human factors involved in level 1 PPE, as identified in prior research. RESULTS: A total of 722 respondents from Israel and 301 respondents from Portugal were included in the analysis. All the respondents reported using level 1 PPE with patients with COVID-19 in the range of several hours daily to several hours weekly. The Cronbach α was .73 for Israel and .75 for Portugal. Responses showed high levels of difficulty, with medians of 4 for items related to discomfort (n=539/688, 78% in Israel; n=328/377, 87% in Portugal), hearing (n=236/370, 64% in Portugal; n=321/642, 50% in Israel), seeing (n=697/763, 89% in Israel; n=317/376, 84% in Portugal), and doffing (n=290/374, 77% in Portugal; n=315/713, 44% in Israel). A factor analysis showed a set of strongly related variables consisting of hearing, understanding speech, and understanding the situation. This suggests that degradation in communication was strongly associated with degradation in situational awareness. A subsequent mediation analysis showed a direct effect of PPE discomfort on situational awareness (P<.001); this was also influenced (mediated) by difficulties in communicating, namely in hearing and understanding speech. CONCLUSIONS: In 2020, the COVID-19 pandemic is paving the way for updating PPE design. The use of already deployed technology affords ample opportunities to improve, adapt, and overcome caveats. The findings here suggest that the use of level 1 PPE with patients with COVID-19 has perceptual and cognitive effects, in addition to physical and ergonomic influences. Efforts should be taken to mitigate the harmful effects of such influences, both regarding the performance of medical actions and the risk of contamination to health care workers. Such efforts involve the design of PPE; the introduction of technologies to enhance vision, hearing, and communicating during the use of PPE; and training staff in using the equipment and in effective communication and teamwork protocols.

Probing deep tissues with laser-induced thermotherapy using near-infrared light.

Optically tunable gold nanoparticles have been widely used in research with near-infrared light as a means to enhance laser-induced thermal therapy since it capitalizes on nanoparticles' plasmonic heating properties. There have been several studies published on numerical models replicating this therapy in such conditions. However, there are several limitations on some of the models which can render the model unfaithful to therapy simulations. In this paper, two techniques of simulating laser-induced thermal therapy with a high-absorbing localized region of interest inside a phantom are compared. To validate these models, we conducted an experiment of an agar-agar phantom with an inclusion reproducing it with both models. The phantom was optically characterized by absorption and total attenuation. The first model is based on the macroperspective solution of the radiative transfer equation given by the diffusion equation, which is then coupled with the Pennes bioheat equation to obtain the temperature. The second is a Monte Carlo model that considers a stochastic solution of the same equation and is also considered as input to the Pennes bioheat transfer equation which is then computed. The Monte Carlo is in good agreement with the experimental data having an average percentage difference of 4.5% and a correlation factor of 0.98, while the diffusion method comparison with experimental data is 61% and 0.95 respectively. The optical characterization of the phantom and its inclusion were also validated indirectly since the Monte Carlo, which used those parameters, was also validated. While knowing the temperature in all points inside a body during photothermal therapy is important, one has to be mindful of the model which fits the conditions and properties. There are several reasons to justify the discrepancy of the diffusion method: low-scattering conditions, absorption, and reduced scattering are comparable. The error bars that are normally associated when characterizing an optical phantom can justify also a part of that uncertainty. For low-size tumors in depth, one may have to increase the light dosage in photothermal therapies to have a more effective treatment.

Bin1 and CD2AP polarise the endocytic generation of beta-amyloid.

The mechanisms driving pathological beta-amyloid (Aß) generation in late-onset Alzheimer's disease (AD) are unclear. Two late-onset AD risk factors, Bin1 and CD2AP, are regulators of endocytic trafficking, but it is unclear how their endocytic function regulates Aß generation in neurons. We identify a novel neuron-specific polarisation of Aß generation controlled by Bin1 and CD2AP We discover that Bin1 and CD2AP control Aß generation in axonal and dendritic early endosomes, respectively. Both Bin1 loss of function and CD2AP loss of function raise Aß generation by increasing APP and BACE1 convergence in early endosomes, however via distinct sorting events. When Bin1 levels are reduced, BACE1 is trapped in tubules of early endosomes and fails to recycle in axons. When CD2AP levels are reduced, APP is trapped at the limiting membrane of early endosomes and fails to be sorted for degradation in dendrites. Hence, Bin1 and CD2AP keep APP and BACE1 apart in early endosomes by distinct mechanisms in axon and dendrites. Individuals carrying variants of either factor would slowly accumulate Aß in neurons increasing the risk for late-onset AD.

ACE Gene Plays a Key Role in Reducing Blood Pressure in The Hyperintensive Elderly After Resistance Training.

Montrezol, FT, Marinho, R, Mota, GdFAd, D'almeida, V, de Oliveira, EM, Gomes, RJ, and Medeiros, A. ACE gene plays a key role in reducing blood pressure in the hyperintensive elderly after resistance training. J Strength Cond Res 33(4): 1119-1129, 2019-Hypertension is a difficult disease to control and exercise training plays a key role in hypertension control. Some individuals are not responsive to exercise training; so, we highlight the polymorphism of I allele of angiotensin-converting enzyme (ACE) as a factor responsible for this lack of responsiveness. The aim of this study was to evaluate the influence of ACE insertion/deletion genotypes on effects of resistance training on blood pressure (BP) and chronic inflammation. Eighty-six hypertensive volunteers, aged between 60 and 80, were evaluated. They performed 16 weeks of resistance training at 50% of 1 maximal repetition. The greatest benefits were seen on homozygous of the Insertion allele, whom presented reduction of systolic blood pressure (SBP: 129.31 ± 13.34 vs. 122.56 ± 9.68 mm Hg, p < 0.001) and diastolic blood pressure (DBP: 79.18 ± 8.05 vs. 70.12 ± 7.71 mm Hg, p < 0.01) during daytime period, and in 24-hour period (SBP: 127.12 ± 13.65 vs. 121.06± 9.68 mm Hg, p < 0.001 and DBP: 71.87 ± 8.39 vs. 68.75 ± 8.72 mm Hg, p < 0.05) and also increased circulating adiponectin levels (4.04 ± 1.79 vs. 6.00 ± 2.81 ng·ml, p < 0.01). Other genotypes showed no changes in BP and biochemical parameters. Our results suggest a cardio protective factor of I allele because only those homozygous showed reductions in BP and increases in adiponectin.

Ankle joint mobility as a predictor of treatment prognosis in patients with chronic venous insufficiency with venous ulcers.

The present study arose from the need to improve treatment of patients with chronic venous insufficiency (CVI) who present with venous ulcers. A total of 40 lower limbs were assessed from 20 patients with healed venous ulcers (C5) or active venous ulcers (C6) who had undergone varicose vein surgery. The relationship between the range of motion of the ankle joint and presence of C5 or C6 venous ulcer was analyzed. For this purpose, normal goniometry findings for this joint were used as a predictor of venous ulcer healing, defined as the outcome. Thus, when identifying reduced ankle joint movement or immobility in these patients, new treatment options could be offered in order to increase joint mobility and prevent or delay CVI complications.

Venous revascularization to treat posterior nutcracker syndrome by transposition of the left gonadal vein: case report.

The Nutcracker Syndrome is manifest in the presence of a symptomatic entrapment of the left renal vein between the abdominal aorta and the superior mesenteric artery. In a more ephemeral variation of this disorder, called the Posterior Nutcracker Syndrome, the renal vein is not compressed anterior to the aorta, but posteriorly, between the artery and the spine. Although there are multiple treatment options, current techniques aim to relieve the symptoms and reduce venous pressure on the left renal vein. This report describes a case of Posterior Nutcracker Syndrome in which the management approach chosen was open surgery, transposing the gonadal vein distally, to the inferior cava vein.

Diagnosis and treatment of the Nutcracker syndrome: a review of the last 10 years.

The nutcracker syndrome is characterized by a group of clinical manifestations caused by compression of the Left Renal Vein. The main symptoms are: macro and micro hematuria, proteinuria, and flank pain. Diagnosis is usually made after excluding other causes, because there are no clinical criteria for diagnosis. Confirmation is by Doppler ultrasonography or computed tomography. Treatment can vary, depending on patient characteristics and the severity of the symptoms, while conservative treatment, open surgery, and endovascular surgery may be employed. Currently, open surgery is still the first-line treatment, but some less invasive approaches are gaining acceptance.

Transcatheter tricuspid valve-in-valve replacement: one-year results : Alternative to surgery in high-risk patients.

Although rheumatic heart disease is becoming uncommon in industrialized countries, its global burden is still significant. We report the case of a 70-year-old male with rheumatic heart disease, who underwent 4 previous heart valve replacement surgeries, and presented to our hospital with refractory heart failure (NYHA functional class IV) due to severe stenosis of a previously implanted tricuspid bioprosthesis. The Heart Team deemed the patient as inoperable/high-risk for surgery. As an alternative, a transcatheter tricuspid valve-in-valve replacement was decided upon and later executed through the right femoral vein, with the insertion of an Edwards SAPIEN XT 29 no. (Edwards Lifesciences, Irvine, CA, USA) through the inferior vena cava, towards the RV, followed by direct implantation in the tricuspid bioprosthesis (valve-in-valve), under rapid pacing, without complications. A substantial clinical and echocardiographic improvement was noted after the procedure and the patient was subsequently discharged in NYHA functional class II. These favourable outcomes persisted through the 1-year follow-up period. This case report adds to the current body of evidence that tricuspid valve implantation stands as a viable and reliable alternative in the treatment of degenerated bioprosthesis in high-surgical-risk patients.

The role of fibrinogen glycation in ATTR: evidence for chaperone activity loss in disease.

Transthyretin amyloidosis (ATTR) belongs to a class of disorders caused by protein misfolding and aggregation. ATTR is a disabling disorder of autosomal dominant trait, where transthyretin (TTR) forms amyloid deposits in different organs, causing dysfunction of the peripheral nervous system. We previously discovered that amyloid fibrils from ATTR patients are glycated by methylglyoxal. Even though no consensus has been reached about the actual role of methylglyoxal-derived advanced glycation end-products in amyloid diseases, evidence collected so far points to a role for protein glycation in conformational abnormalities, being ubiquitously found in amyloid deposits in Alzheimer's disease, dialysis-related amyloidosis and Parkinson's diseases. Human fibrinogen, an extracellular chaperone, was reported to specifically interact with a wide spectrum of stressed proteins and suppress their aggregation, being an interacting protein with TTR. Fibrinogen is differentially glycated in ATTR, leading to its chaperone activity loss. Here we show the existence of a proteostasis imbalance in ATTR linked to fibrinogen glycation by methylglyoxal.

Insights into the molecular mechanism of protein native-like aggregation upon glycation.

Several human neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Familial Amyloidotic Polyneuropathy, have long been associated with, structural and functional changes in disease related proteins leading to aggregation into amyloid fibrils. Such changes can be triggered by post-translational modifications. Methylglyoxal modifications have been shown to induce the formation of small and stable native-like aggregates in the case of the amyloidogenic proteins insulin and α-synuclein. However, the fundamental biophysical mechanism underlying such methylglyoxal-induced protein aggregation is not yet fully understood. In this work cytochrome c (Cyt c) was used as a model protein for the characterization of specific glycation targets and to study their impact on protein structure, stability, and ability to form native-like aggregates. Our results show that methylglyoxal covalently modifies Cyt c at a single residue and induces early conformational changes that lead to the formation of native-like aggregates. Furthermore, partially unfolded species are formed, but do not seem to be implicated in the aggregation process. This shows a clear difference from the amyloid fibril mechanisms which involve partially or totally unfolded intermediates. Equilibrium-unfolding experiments show that glycation strongly decreases Cyt c conformational stability, which is balanced with an increase of conformational stability upon aggregation. Data collected from analytical and spectroscopic techniques, along with kinetic analysis based on least-squares parameter fitting and statistical model discrimination are used to help to understand the driving force underlying glycation-induced native-like aggregation, and enable the proposal of a comprehensive thermodynamic and kinetic model for native-like aggregation of methylglyoxal glycated Cyt c.

Spatial memory in sedentary and trained diabetic rats: molecular mechanisms.

Diabetes mellitus is a chronic disease that has been associated with memory loss, neurological disorders, and Alzheimer's disease. Some studies show the importance of physical exercise to prevent and minimize various neurological disorders. It is believed that the positive effects of exercise on brain functions are mediated by brain insulin and insulin-like growth factor-1 (IGF-1) signaling. In this study, we investigate the role of swimming exercise training on hippocampus proteins related to insulin/IGF-1 signaling pathway in Type 1 diabetic rats and its effects on spatial memory. Wistar rats were divided into four groups namely sedentary control, trained control, sedentary diabetic (SD), and trained diabetic (TD). Diabetes was induced by Alloxan (ALX) (32 mg/kg b.w.). The training program consisted in swimming 5 days/week, 1 h/day, per 6 weeks, supporting an overload corresponding to 90% of the anaerobic threshold. We employed ALX-induced diabetic rats to explore learning and memory abilities using Morris water maze test. At the end of the training period, the rats were sacrificed 48 h after their last exercise bout when blood samples were collected for serum glucose, insulin, and IGF-1 determinations. Hippocampus was extracted to determinate protein expression (IR, IGF-1R, and APP) and phosphorylation (AKT-1, AKT-2, Tau, and ß-amyloide proteins) by Western Blot analysis. All dependent variables were analyzed by two-way analysis of variance with significance level of 5%. Diabetes resulted in hyperglycemia and hypoinsulinemia in both SD and TD groups (P < 0.05); however, in the training-induced group, there was a reduction in blood glucose in TD. The average frequency in finding the platform decreased in SD rats; however, exercise training improved this parameter in TD rats. Aerobic exercise decreased Tau phosphorylation and APP expression, and increased some proteins related to insulin/IGF-1 pathway in hippocampus of diabetic rats. Thus, these molecular adaptations from exercise training might contribute to improved spatial learning and memory in diabetic organisms.

The glyoxalase pathway: the first hundred years... and beyond.

The discovery of the enzymatic formation of lactic acid from methylglyoxal dates back to 1913 and was believed to be associated with one enzyme termed ketonaldehydemutase or glyoxalase, the latter designation prevailed. However, in 1951 it was shown that two enzymes were needed and that glutathione was the required catalytic co-factor. The concept of a metabolic pathway defined by two enzymes emerged at this time. Its association to detoxification and anti-glycation defence are its presently accepted roles, since methylglyoxal exerts irreversible effects on protein structure and function, associated with misfolding. This functional defence role has been the rationale behind the possible use of the glyoxalase pathway as a therapeutic target, since its inhibition might lead to an increased methylglyoxal concentration and cellular damage. However, metabolic pathway analysis showed that glyoxalase effects on methylglyoxal concentration are likely to be negligible and several organisms, from mammals to yeast and protozoan parasites, show no phenotype in the absence of one or both glyoxalase enzymes. The aim of the present review is to show the evolution of thought regarding the glyoxalase pathway since its discovery 100 years ago, the current knowledge on the glyoxalase enzymes and their recognized role in the control of glycation processes.

Elemental analysis using portable X-ray fluorescence: Guidelines for the study of dry human bone.

OBJECTIVE: X-ray fluorescence (XRF) is a non-destructive technique that measures the elemental concentration of different materials, including human bone. Recently, it began to be applied to paleopathological studies due to the development of portable devices and their relative ease of use. However, the lack of uniform procedures hampers comparability and reproducibility. This paper aims to provide guidelines for an efficient and standardized evaluation of bone elemental composition with a portable XRF (pXRF) device. MATERIALS: This technical note is based on the application of the Thermo Scientific Niton XL3t 900 GOLDD+. METHODS: This work includes suggestions for the choice and preparation of human bone samples, both from archaeological context and documented collections, and methodological procedures in pXRF setup, such as choice of calibration, assessment of accuracy, and analysis run time. Additionally, recommendations for data validation and statistical analysis are also included. CONCLUSIONS: This technique has great potential in paleopathology since bone chemical variations may be associated with different pathological conditions, environmental contamination (e.g., lead), and/or administered treatments, such as mercury. Following an expected increase in the number of studies, it is essential to establish good practices that allow results from different researchers to be comparable. SIGNIFICANCE: X-ray fluorescence is a non-destructive technique that measures small concentrations (ppm) of elements from magnesium (12Mg) through bismuth (83Bi). LIMITATIONS: pXRF does not detect elements lighter than Mg, and its lower energy excitation penetrates less than other techniques. SUGGESTIONS FOR FURTHER RESEARCH: Other research groups should test these guidelines and comment on their usefulness and replicability.