Biochemical algorithm to identify individuals with ALPL variants among subjects with persistent hypophosphatasaemia.

BACKGROUND: Hypophosphatasia (HPP) is a rare and underdiagnosed condition characterized by deficient bone and teeth mineralization. The aim of this study was first, to evaluate the diagnostic utility of employing alkaline phosphatase (ALP) threshold levels to identify adults with variants in ALPL among individuals with persistently low ALP levels and second, to determine the value of also including its substrates (serum pyridoxal-5'-phosphate-PLP-and urinary phosphoetanolamine-PEA) for this purpose in order to create a biochemical algorithm that could facilitate the diagnostic work-up of HPP. RESULTS: The study population comprised 77 subjects with persistent hypophosphatasaemia. They were divided into two groups according to the presence (+GT) or absence (-GT) of pathogenic ALPL variants: 40 +GT and 37 -GT. Diagnostic utility measures were calculated for different ALP thresholds and Receiver Operating Characteristic (ROC) curves were employed to determine PLP and PEA optimal cut-off levels to predict the presence of variants. The optimal threshold for ALP was 25 IU/L; for PLP, 180 nmol/L and for PEA, 30 µmol/g creatinine. Biochemical predictive models were assessed using binary logistic regression analysis and bootstrapping machine learning technique and results were then validated. For ALP < 25 UI/L (model 1), the area under curve (AUC) and the 95% confidence intervals (CI) was 0.68 (95% CI 0.63-0.72) and it improved to 0.87 (95% CI 0.8-0.9), when PEA or PLP threshold levels were added (models 2 and 3), reaching 0.94 (0.91-0.97) when both substrates were included (model 4). The internal validation showed that the addition of serum PLP threshold levels to the model just including ALP improved significantly sensitivity (S) and negative predictive value (NPV) - 100%, respectively- with an accuracy (AC) of 93% in comparison to the inclusion of urinary PEA (S: 71%; NPV 75% and AC: 79%) and similar diagnostic utility measures as those observed in model 3 were detected when both substrates were added. CONCLUSIONS: In this study, we propose a biochemical predictive model based on the threshold levels of the main biochemical markers of HPP (ALP < 25 IU/L and PLP > 180 nmol/L) that when combined, seem to be very useful to identify individuals with ALPL variants.

Predictive modeling of hypophosphatasia based on a case series of adult patients with persistent hypophosphatasemia.

Approximately half of individuals with hypophosphatasemia (low levels of serum alkaline phosphatase) have hypophosphatasia, a rare genetic disease in which patients may have stress fractures, bone and joint pain, or premature tooth loss. We developed a predictive model based on specific biomarkers of this disease to better diagnose this condition. INTRODUCTION: Hypophosphatasemia is a condition in which low levels of alkaline phosphatase (ALP) are detected in the serum. Some individuals presenting with this condition may have a rare genetic disease called hypophosphatasia (HPP), which involves mineralization of the bone and teeth. Lack of awareness of HPP and its nonspecific symptoms make this genetic disease difficult to diagnose. We developed a predictive model based on biomarkers of HPP such as ALP and pyridoxal 5'-phosphate (PLP), because clinical manifestations sometimes are not recognized as symptoms of HPP. METHODS: We assessed 325,000 ALP results between 2010 and 2015 to identify individuals suspected of having HPP. We performed univariate and multivariate analyses to characterize the relationship between hypophosphatasemia and HPP. Using several machine learning algorithms, we developed several models based on biomarkers and compared their performance to determine the best model. RESULTS: The final cohort included 45 patients who underwent a genetic test. Half (23 patients) showed a mutation of the ALPL gene that encodes the tissue-nonspecific ALP enzyme. ALP (odds ratio [OR] 0.61, 95% confidence interval [CI] 0.3-0.8, p = 0.01) and PLP (OR 1.06, 95% CI 1.01-1.15, p = 0.04) were the only variables significantly associated with the presence of HPP. Support vector machines and logistic regression were the machine learning algorithms that provided the best predictive models in terms of classification (area under the curve 0.936 and 0.844, respectively). CONCLUSIONS: Given the high probability of a misdiagnosis, its nonspecific symptoms, and a lack of awareness of serum ALP levels, it is difficult to make a clinical diagnosis of HPP. Predictive models based on biomarkers are necessary to achieve a proper diagnosis. Our proposed machine learning approaches achieved reasonable performance compared to traditional statistical methods used in biomedicine, increasing the likelihood of properly diagnosing such a rare disease as HPP.

Recycling of polymeric composites from industrial waste by pyrolysis: Deep evaluation for carbon fibers reuse.

The use of polymeric composite on transport applications as reinforcement material has been increased due to the low fuel consumption when replacing heavier materials. It is estimated that 170,000 tons of polymeric composites will be discarded by 2025, and recycling processing for carbon fibers recovery is required to save primary energy and reduce waste. Among the current techniques, pyrolysis processing has been most effective. On the other hand, innovation must maintain the structure for reuse since physical and mechanical properties are important for recycled materials. For this reason, the goal of the present study was the recycling of polymeric composite by pyrolysis. The recovered carbon fibers were analyzed in SEM and EDS to verify surface defects compared with virgin carbon fibers. The effect of temperature, time, and atmosphere were investigated. Results showed that at 550 °C for 1 h, it was possible to obtain free carbon fibers from the polymeric matrix. After the pyrolysis process in this condition, the fibers had no pores, material fracture, and carbonization. This paper contributes to the widening and systematizing knowledge on effectiveness and understanding polymeric composites recycling for carbon fiber recovery, maintaining its structure for reuse.

Can we identify individuals with an ALPL variant in adults with persistent hypophosphatasaemia?

BACKGROUND: Hypophosphatasia (HPP) is an inborn error of metabolism characterized by low levels of serum alkaline phosphatase (ALP). Scarce evidence exists about features that should signal the potential association between hypophosphatasaemia and HPP in adults. The aim of this study is to estimate the prevalence of ALPL variants in subjects with persistent hypophosphatasaemia and determine the associated clinical and laboratory features. For this cross-sectional study, laboratory records of 386,353 subjects were screened by measurement of ALP activity. A total of 85 (0.18%) subjects with persistent hypophosphatasaemia (≥2 serum alkaline phosphatase-ALP-measurements ≤35 IU/L and none > 45 IU/L) were included (secondary causes previously discarded). ALPL genetic testing and a systematized questionnaire to retrieve demographic, clinical and laboratory data were performed. Descriptive analysis and logistic regression models were employed to identify the clinical and laboratory characteristics associated with ALPL variants. RESULTS: Forty subjects (47%) had a variant(s) in ALPL. With regard to clinical characteristics, the presence of an ALPL variant was significantly associated only with musculoskeletal pain (OR: 7.6; 95% IC: 1.9-30.9). Nevertheless, a trend to present more dental abnormalities (OR: 3.6; 95% IC: 0.9-13.4) was observed. Metatarsal stress fractures were also more frequent (4 vs 0; p < 0.05) in this group. Regarding laboratory features, median ALP levels were lower in subjects with ALPL variants (26 vs 29 IU/L; p < 0.005). Interestingly, the threshold of ALP levels < 25 IU/L showed a specificity, positive predictive value and positive likelihood ratio of 97.8, 94.4% and 19.8 to detect a positive ALPL test, respectively. CONCLUSIONS: In subjects with persistent hypophosphatasaemia -secondary causes excluded- one out of two presented ALPL variants. Musculoskeletal pain and ALP levels < 25 IU/L are associated with this variant(s). In this scenario, ALP levels < 25 IU/L seem to be very useful to identify individuals with the presence of an ALPL variant.

Development and standardization of a western blotting test for detection of antibodies against B. abortus / Desenvolvimento e padronização do teste Western blotting para detecção de anticorpos contra B. abortus

Brucellosis is an infectious disease caused by bacteria of the genus Brucella spp. with diagnosis based on use of serological techniques. The present study aimed to develop and standardize a western blotting (WB) test for detection of antibodies against B. abortus. Samples from two groups of cattle were analyzed: group I: 60 serum samples from true positive and true negative vaccinated animals (30 positive samples from infected animals according to rose bengal test (RBT), 2-mercaptoethanol, serum agglutination test (SAT) and complement fixation test (CFT) and 30 RBT negatives samples); group II: 383 field samples (90 positive and 293 CFT negative sera). The most reactive band in the western blotting, which properly identified and separated infected from non - infected had a molecular weight of ≤ 20kDa. The sensitivity, specificity and accuracy of the WB compared to RBT was 93%, 99%, 98%, respectively and k= 0.938. When compared to CFT, the sensitivity, specificity and accuracy of the WB was 97%, 98% and 97%, respectively and k= 0.929. The WB developed and standardized in the present study is a serological test with potential use as a confirmatory test for the diagnosis of bovine brucellosis.(AU)

A brucelose é uma doença infectocontagiosa, causada por bactérias do gênero Brucella spp., com diagnóstico baseado no emprego de técnicas sorológicas. Objetivou-se neste estudo desenvolver e padronizar um teste Western blotting (WB) para detecção de anticorpos contra B. abortus. Foram analisados dois grupos de amostras bovinas: grupo I, com 60 amostras de animais verdadeiros positivos e verdadeiros negativos vacinados (30 amostras positivas de animais infectados e positivos nos testes de antígeno acidificado tamponado (AAT), 2 - mercaptoetanol (2 - ME), soroaglutinação lenta em tubos (SAT) e fixação do complemento e de 30 amostras negativas no AAT); grupo II, com 383 amostras de campo, sendo 90 soropositivas e 293 soronegativas no TFC. O resultado da análise do WB revelou peso molecular ≤20kDa como sendo a área mais reativa e característica para identificação e separação dos animais infectados dos não infectados. A sensibilidade, a especificidade e a acurácia do WB, quando este foi comparado com o AAT, foram, respectivamente, 93%, 99% e 98%, e k= 0,938. Quando comparadas com a TFC, a sensibilidade, a especificidade e a acurácia foram 97%, 98% e 97%, respectivamente, e k= 0,929. O WB padronizado neste estudo mostrou-se um teste sorológico com potencial uso como teste confirmatório no diagnóstico da brucelose bovina.(AU)

Abnormal bone turnover in individuals with low serum alkaline phosphatase.

The clinical spectrum of hypophosphatasia (HPP) is broad and variable within families. Along severe infantile forms, adult forms with mild manifestations may be incidentally discovered by the presence of low alkaline phosphatase (ALP) activity in serum. However, it is still unclear whether individuals with persistently low levels of ALP, in the absence of overt manifestations of HPP, have subclinical abnormalities of bone remodeling or bone mass. The aim of this study was to obtain a better understanding of the skeletal phenotype of adults with low ALP by analyzing bone mineral density (BMD), bone microarchitecture (trabecular bone score, TBS), and bone turnover markers (P1NP and ß-crosslaps). We studied 42 individuals with persistently low serum ALP. They showed lower levels of P1NP (31.4 ± 13.7 versus 48.9 ± 24.4 ng/ml; p = 0.0002) and ß-crosslaps (0.21 ± 0.17 versus 0.34 ± 0.22 ng/ml, p = 0.0015) than individuals in the control group. There were no significant differences in BMD, bone mineral content, or TBS. These data suggest that individuals with hypophosphatasemia have an overall reduction of bone turnover, even in the absence of overt manifestations of HPP or low BMD. We evaluated bone mineral density (BMD), bone microarchitecture, and bone turnover markers in patients with low serum levels of alkaline phosphatase. Our results show that these patients have low bone remodeling even in the absence of BMD abnormalities, thus supporting the recommendation of avoiding antiresorptives such as bisphosphonates in these subjects.

Physical analyses of compost from composting plants in Brazil.

Nowadays the composting process has shown itself to be an alternative in the treatment of municipal solid wastes by composting plants. However, although more than 50% of the waste generated by the Brazilian population is composed of matter susceptible to organic composting, this process is, still today, insufficiently developed in Brazil, due to low compost quality and lack of investments in the sector. The objective of this work was to use physical analyses to evaluate the quality of the compost produced at 14 operative composting plants in the Sao Paulo State in Brazil. For this purpose, size distribution and total inert content tests were done. The results were analyzed by grouping the plants according to their productive processes: plants with a rotating drum, plants with shredders or mills, and plants without treatment after the sorting conveyor belt. Compost quality was analyzed considering the limits imposed by the Brazilian Legislation and the European standards for inert contents. The size distribution tests showed the influence of the machinery after the sorting conveyer on the granule sizes as well as the inert content, which contributes to the presence of materials that reduce the quality of the final product.

Utilization of magnetic and electrostatic separation in the recycling of printed circuit boards scrap.

The progress of the technology is directly related to the growth of production and consumption of electrical/electronics equipment, especially of personal computers. This type of equipment has a relatively short average lifetime, 2-3 years. The amount of defective or obsolete equipment has been increasing substantially; consequently its disposition and/or recycling should be studied. In this work, printed circuit boards, which are used in personal computers, were studied in order to recover the metals in the circuit boards through mechanical processing, such as crushing, screening, as well as magnetic and electrostatic separation. The results obtained demonstrate the feasibility of using these processes to separate metal fractions from polymers and ceramics, and that it is possible to obtain a fraction concentrated in metals containing more than 50% on average of copper, 24% of tin and 8% of lead.

Evaluation of the incorporation ratio of ZnO, PbO and CdO into cement clinker.

Zinc, lead, and cadmium are minor elements that might be brought by wastes to the cement kilns. This work studies the incorporation ratio of ZnO, PbO, and CdO when they are added to the clinker raw material. The cement raw material used in this work was prepared by mixing pure compounds, this choice was made to avoid the effect of other elements and provide a better understanding of the behavior of these metals during the clinkering process. The samples contained additions of 0.05, 0.10, 0.30, 0.50, 0.80 and 1.00 wt.% of a specific oxide (ZnO, PbO, or CdO) to the clinker raw-meal. The chlorine influence in the ZnO incorporation ratio was also evaluated. A device to simulate the thermal cycle imposed on the charge during the clinker production was used to evaluate the incorporation ratio of these oxides as well as thermogravimetric tests. The products of the tests in the simulator device were submitted to X-ray fluorescence chemical analysis or energy disperse scanning (EDS) microprobe analysis. The results led to the conclusions that the evaporation of Zn in cements kilns is due to the chlorine content and the Pb and Cd incorporation ratio stands around 50 wt.%.

Determination of Cu and Ni incorporation ratios in Portland cement clinker.

Cu and Ni are metals found in galvanic sludges; these sludges are considered hazardous due to their heavy metal content. The main objective of this work is to determine the incorporation amount of Cu and Ni in Portland clinker when a galvanic sludge containing these metals is added to the clinker raw-material. The influence of this addition on the clinkering reactions is evaluated as well as the possibility of co-incinerating galvanic sludges containing Cu and Ni in rotary cement kilns. This study also characterizes the galvanic sludge. Samples were prepared by additions from 0.25 to 5 wt.% of a galvanic sludge to an industrial clinker raw-material. The clinkering process was simulated in a laboratory device. The following techniques were applied to characterize the raw materials and the products of the tests: chemical analysis, differential thermal analysis (DTA) and thermogravimetric analysis (TG). Leaching tests were performed in the produced clinker samples in order to verify the incorporation of the studied metals in the clinker structure. The results led to the conclusion that additions of up to 2 wt.% of a galvanic sludge containing 2.4 wt.%Cu and 1.2 wt.% Ni to clinker raw-material do not affect the clinkering reactions and that these metals are totally incorporated into the clinker.

Chloride influence on the incorporation of Cr(2)O(3) and NiO in clinker: a laboratory evaluation.

Co-incinerating wastes in cement rotary kilns may introduce elements not usually found in the raw material into the process or even increase the quantity of some minor elements. Chromium and nickel are present in some electroplating sludges. These wastes are hazardous and must be treated and disposed of in a controlled landfill. The objective of this work was to study the incorporation of chromium and nickel oxides when they were added to clinker raw meal. The clinker raw meal used in this study was prepared by mixing pure compounds in the ratio that made it possible to obtain the same phases of an industrial Portland clinker at the end of the heating process. Twelve samples were prepared by adding 0.05, 0.1, 0.3, 0.5, 0.8 and 1.0wt.% of Cr(2)O(3) and 0.05, 0.1, 0.3, 0.5, 0.8 and 1.0wt.% of NiO to the base charge. Also, four more samples were prepared with additions of 0.6% Cr(2)O(3) and 0.1% NaCl, 0.7% Cr(2)O(3) and 0.1% KCl, 0.8% NiO and 0.1% NaCl and 0.8% NiO and 0.1% KCl. In order to study the Cr and Ni incorporation, thermogravimetric (TG) tests were performed, as well as tests in an assembled experimental device. The products were characterized by X-ray fluorescence chemical analysis, microprobe analyses by energy disperse scanning (EDS) and leaching tests. The results showed that the chromium and nickel added were incorporated into the clinker, even when chlorides were present.

Treatment of chromium plating process effluents with ion exchange resins.

The surface treatment industry deals with various heavy metals, including the elements Cr, Zn, Ni, Cd, and Cu. Conventional treatments of effluents generate class I solid residue. The aim of this investigation was to study the viability of ion exchange as an alternative process for treatment of rinse water and to determine the efficacy of two ion exchange systems, System 1: "strong" cationic resin-"strong" anionic resin and System 2: "strong" cationic resin-"weak" anionic resin. Commercial resins and solutions taken from rinse tanks of chromium plating companies were used in this investigation. A two-column system, one for the cationic resin and another for the anionic resin, both with 150 ml capacity was mounted. The solution was percolated at a rate of 10 ml/min. The following solutions were used for regeneration of the resins: 2% H2SO4 for the cationic and 4% NaOH for the anionic. The percolated solutions revealed chromium contents of less than 0.25 mg/l, independent of the system used. The "strong" cationic resin-"weak" anionic resin gave excellent regeneration results. The "strong" cationic-"strong" anionic resin presented problems during regeneration, and did not release the retained ions after percolation of 2000 ml of 4% NaOH solution. It is concluded that for this type of treatment, the system composed of "strong" cationic resin and "weak" anionic resin is more appropriate.

Thermal behaviour of chromium electroplating sludge.

Galvanic sludge is classified as a hazardous waste and incineration is one of the techniques used for its treatment. The aim of this work is to study the thermal behavior of a galvanic sludge which contains only chromium as a restriction metal. Simultaneous DTA/TG coupled with mass spectrometer tests were performed to characterize the thermal behavior of the sludge. Besides thermal analysis, sludge samples were heated in a specially designed furnace and these samples were submitted to X-ray diffraction. Vapor from the heated sludge was condensed and the particles were analyzed by EDS microprobe coupled in a scanning electron microscope. The slag formed after the calcination of the galvanic sludge was mainly composed of a mixture of calcium phosphate and fluoride. and minor concentrations of metals. A total weight loss of 34% was observed. The greatest part of this weight loss corresponds to CO2, H2O and SO2. H2O is liberated in the temperature range of 500-1,250 degrees C. CO2 in the range of 500-750 degrees C and SO2 near 1,000 degrees C. Chromium evaporation was not observed in relevant quantities, about 99.6% of the Cr remained incorporated in the slag.