Phosphorus Assay Research Articles

Verification of the analytical performance of the serum phosphorus assay on the Abbott Alinity ci®: Experience of the central laboratory Mohammed VI University Hospital of Oujda

Introduction: In our study, we aimed to evaluate the analytical performance of the serum phosphorus determination method using an Abbott kit on the Alinity c automaton at the biochemistry laboratory of Mohammed VI University Hospital of Oujda. Materials and methods: We evaluated the performance of the kit using flexible scope A and conducted a thorough performance study on the Alinity c automaton. This study encompassed assessments of repeatability, reproducibility and comparisons of results obtained from two Alinity c automatons. Results: The obtained results met the acceptability criteria recommended by the supplier and the French Society of Clinical Biology(Société Française de Biologie Clinique SFBC) Valtec protocol, indicating overall satisfaction with the study. The Alinity c automaton exhibited the necessary analytical performance to ensure accurate and dependable determination of phosphorus levels. Discussion: Ensuring accurate and reliable results, the verification of the serum phosphorus determination method in the medical laboratory is crucial. This process entails implementing quality control measures, calibration, and comparing with established reference methods. It guarantees that the laboratory's phosphorus testing method is precise, accurate, and compliant with industry standards, thereby upholding the quality of patient care. Conclusion: The verification study of the serum phosphorus determination method yielded satisfactory results, providing high reliability to the test results from the central laboratory at Mohammed VI University Hospital of Oujda. This verification study serves as a strong foundation in the accreditation process, ensuring the accuracy and quality of laboratory testing, and enhancing the overall reliability of patient care

A-129 Analytical Performance Evaluation of Vitamin D, Intact Parathyroid Hormone, and Inorganic Phosphorus on the Atellica CI 1900 Analyzer

Abstract Background The Atellica® CI 1900 Analyzer is an automated, mid-throughput, integrated chemistry and immunoassay analyzer utilizing both Atellica CH and Atellica IM assays. This study was designed to evaluate the analytical performance of the Atellica IM Vitamin D (VitD) and Intact Parathyroid Hormone (PTH) and Atellica CH Inorganic Phosphorus (IP) assays* on the Atellica CI 1900 Analyzer*. Methods The Atellica CI 1900 VitD, PTH, and IP assays use the same reagents and calibrators as the Atellica IM VitD and PTH and CH IP assays. Precision and method comparison (MC) were used as performance indicators for the Atellica CI 1900 Analyzer. Precision studies were performed according to CLSI EP05-A3 using native and contrived human serum (VitD and IP) or plasma (PTH) samples. One aliquot of each sample pool was tested in duplicate in two runs per day >2 h apart on each analyzer for >20 days. MC studies were performed according to CLSI EP09-A3. Native and contrived human samples were analyzed using the Atellica IM VitD and PTH assays on both the Atellica IM and Atellica CI 1900 Analyzers. For IP, native and contrived human samples were analyzed using the Atellica CH IP assay on both the Atellica CH and Atellica CI 1900 Analyzers. Results Representative precision and MC results for each assay across indicated sample ranges are listed in the table. For the three assays tested, repeatability and within-lab %CVs were <4.5% and <10%, respectively. Slopes determined by the Deming linear regression model were approximately equal to 1. Conclusion Evaluation of the Atellica IM VitD and PTH and Atellica CH IP assays using the Atellica CI 1900 Analyzer demonstrated good precision and equivalent performance compared to the same assays on their respective Atellica IM and Atellica CH Analyzers. *The products/features mentioned are not commercially available in all countries. Their future availability cannot be guaranteed.

Investigating the Potential of Lipids for Use as Biomarkers for Glioblastoma via an Untargeted Lipidomics Approach.

The types and functions of lipids involved in glioblastoma (GB) are not well known. Lipidomics is a new field that examines cellular lipids on a large scale and novel aplication of lipidomics in the biomedical sciences have emerged. This study aimed to investigate the potential of blood lipids for use as biomarkers for the diagnosis of GB via untargated lipidomic approach. Gaining a deeper understanding of lipid metabolism in patients with GB can contribute to the early diagnosis with GB patiens and also development of novel and better therapeutic options. This study was performed using blood samples collected from 14 patients (eight females and six males) and 14 controls (eight females and six males). Lipids were extracted from blood samples and quantified using phosphorus assay. Lipid profiles of between patients with GB and controls were compared via an untargeted lipidomics approach using 6530 Accurate-Mass Q-TOF LC/MS mass spectrometer. According to the results obtained using the untargeted lipidomics approach, differentially regulated lipid species, including fatty acid (FA), glycerolipid (GL), glycerophospholipid (PG), saccharolipid (SL), sphingolipid (SP), and sterol lipid (ST) were identified between in patients with GB and controls. Differentially regulated lipids were identified in patients with GB, and these lipid species were predicted as potential biomarkers for diagnosis of GB.

Incidence of Refeeding Syndrome in Critically Ill Children With Nutritional Support

IntroductionEarly enteral nutrition is recommended for critically ill children, potentially exposing those who are undernourished to the risk of refeeding syndrome. However, data on its incidence is lacking, and the heterogeneity of diagnostic criteria and frequent electrolyte disorders in this population make its diagnosis complex. In 2020, the American Society for Parenteral and Enteral Nutrition (ASPEN) developed consensus recommendations for identifying patients at risk and with refeeding syndrome. These state that undernourished children are considered at risk of refeeding syndrome; those who develop one significant electrolyte disorder (decrease ≥ 10% in phosphorus, potassium, and/or magnesium) within the first five days of nutritional support, combined with a significant increase in energy intake, are considered to have refeeding syndrome. The aim of this study was to determine the incidence of refeeding syndrome according to the ASPEN definition in critically ill children on nutritional support.Materials and MethodsA secondary analysis of two prospective cohorts conducted in a tertiary pediatric intensive care unit in France was undertaken, and additional data were retrospectively collected. Children included were those (0–18 years) admitted to the pediatric intensive care unit with a minimum of one phosphorus, potassium, and/or magnesium assay and who received exclusive or supplemental nutritional support. Undernourished children (body mass index z-score < –2 standard deviations) were considered at risk of refeeding syndrome. The ASPEN critiera were used to identify those with probable refeeding syndrome.ResultsA total of 1,261 children were included in the study, with 199 children (15.8%) classified as undernourished, who were at risk of refeeding syndrome. Of these, 93 children were identified as having probable refeeding syndrome, giving an overall incidence of 7.4%. The incidence rate among at-risk children was 46.7%. Most patients (58.1%) were classified as having severe refeeding syndrome.ConclusionRefeeding syndrome remains difficult to diagnose in critically ill children, due to frequent confounding factors impacting electrolyte plasma levels. These findings suggest that refeeding syndrome incidence may be high in undernourished children, and that refeeding syndromes can be severe. Further prospective studies using the ASPEN definition and risk criteria are required.

Phosphate mining activities affect crop rhizosphere fungal communities

Phosphate mining releases heavy metals into the surrounding environment. In this study, the effects of phosphate mining on rhizosphere soil fungi in surrounding crops, including Lactuca sativa var. angustata, Glycine max (L.) Merr., and Triticum aestivum L., were assessed. Phosphate mining significantly reduced the crop rhizosphere fungal diversity (P < 0.05). The relative abundances of Fusarium and Epicoccum increased in mining rhizosphere soil compared with the baseline. Beta diversity analysis indicated that phosphate mining led to the differentiation of fungal community structure in plant rhizospheres. Guild analysis indicated that different plant rhizosphere fungi developed various guilds in response to phosphate mining stress. Nine fungi were isolated from soil samples, with solubilization index values ranging from 1.1 to 2.5. Two efficient phosphate solubilizers, Epicoccum nigrum and Fusarium verticillioides, were enriched in phosphate mining rhizosphere soil samples. The dissolution kinetics of inorganic phosphorus and alkaline phosphatase activity assay showed strong phosphorus dissolution ability of the isolated fungi. Penicillium aculeatum, Trichoderma harzianum, Chaetomium globosum, and F. verticillioides showed strong tolerance to multiple heavy metals. This study furthers our understanding of how rhizosphere fungal ecology is affected by phosphate mining and provides important resources for the remediation of phosphate mining soil pollution.

Rapid colorimetric methods for analysis of pH, extractable aluminium and Colwell phosphorus in soils

Context Analytical procedures and technologies for soil analyses can be prohibitively expensive for small laboratories and researchers in developing countries. There is a need for low cost and high-throughput methods for assaying pH, extractable aluminium and phosphorus when conducting field trials on acid soils. Aims We investigated methods to develop rapid yet inexpensive colorimetric assays for the assay of pH, extractable aluminium and Colwell phosphorus in soil extracts. Methods We developed a colorimetric method to measure soil pH enabling pH to be quantified in a high-throughput assay. Similarly, two existing methods for extractable aluminium and Colwell P were modified for high throughput assays also using microtiter plates. Key results All three methods yielded linear relationships when using absorbance to quantify the parameters with the high throughput methods. Furthermore, there was a strong correlation between pH values of the soil samples obtained with the colorimetric assay and pH values measured with a glass electrode. Conclusions We demonstrated that the rapid assays for all three methods can be implemented to characterise field sites through the mapping of distributions for extractable Al, Colwell P and pH. Implications The high-throughput methods described here will be useful for researchers who conduct field trials to map variations in soil pH, soluble Al and Colwell P. Although the focus of the current work was on acid soils, the colorimetric pH and Colwell P methods can also be applied to non-acid soils.

Dye sensitized Ti3C2 MXene-based highly sensitive homogeneous photoelectrochemical sensing of phosphate through decomposition of methylene blue-encapsulated zeolitic imidazolate framework-90

The previously reported homogeneous photoelectrochemical (PEC) sensor often suffers from the shortcomings of complicated dye-labeling procedure, poor photocurrent intensity, and weak stability. Exploiting novel homogeneous PEC sensors to circumvent above limitations is badly instant but faces a major challenge. This study presents a Ti3C2 MXene-based label-free homogeneous PEC sensor for highly sensitive analysis of phosphorus used methylene blue (MB) sensitized MXene@ITO photoelectrodes and functional zeolitic imidazolate framework-90 (ZIF-90). The MB sensitized MXene@ITO photoelectrodes exhibited excellent stability and elevation of photocurrent intensity. The MB was performed to encapsulate into ZIF-90 to form MB@ZIF-90 with one-step strategy. The prepared MB@ZIF-90 could be decomposed by target phosphorus due to the stronger coordination between phosphorus and Zn2+. As compared to the case where phosphorus was absent, a lot of MB was released and diffused to the MXene@ITO photoelectrode surface, and markedly increased PEC current was gained. Therefore, via these targets induced MB release mode and MB sensitized Ti3C2 MXene@ITO photoelectrodes, a high-performance homogeneous PEC phosphorus assay is realized, with a detection limit down to 0.21 μM. The phosphorus analysis with recovery ranged from 98.3% to 103.4% in environmental and biological samples, demonstrating the potential applicability of this PEC sensor.

Genetic Divergence in Corn Genotypes for High and Low Phosphorus in Pará, Brazil

Aims: The objective of this study was to estimate the genetic divergence between ten corn genotypes in the 2017/18 crop, under high and low phosphorus.&#x0D; Study Design: The experimental design used in each test was randomized blocks, the treatments were: ten genotypes in two levels of phosphorus and three replications.&#x0D; Place and Duration of Study: Sítio Vitória, municipality of Santa Maria das Barreiras, state of Pará, Brazil, in the 2017/18 crop.&#x0D; Methodology: The experimental plot consisted of four lines five meters long, spaced with 0.90 m between the lines, with approximately 55,000 plants per hectare in the harvest. The genotypes used: 2B655, AG 1051, AG 8088, AL BANDEIRANTE, ANHEMBI, BR 206, BRS 3046, CATIVERDE, ORION e PR 27D28. The following agronomic characteristics were evaluated: plant height, ear height, ear diameter, ear length, number of grains per row, yield per plant and grain yield. Genetic divergence was estimated from Mahalanobis distances and genotypes were grouped by Tocher optimization methods.&#x0D; Results: Genetic dissimilarity measurements, at each dose of phosphorus, showed a high magnitude (D2= 9.72 to 1484.87). Cluster analysis separated the genotypes into four groups at low phosphorus and two groups at high phosphorus. The characteristics that most contributed to genetic divergence, in the two levels of phosphorus, were yield per plant and grain yield.&#x0D; Conclusion: There was a higher genetic divergence between genotypes AG 1051 and BANDEIRANTE in the low phosphorus assay and between the genotypes ANHEMBI and AL BANDEIRANTE in the high phosphorus assay. With this, these crosses are promising to obtain lineages in both tests.

Novel approach for pathogenesis of osteoporosis in ovariectomized rats as a model of postmenopausal osteoporosis.

Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Menopausal transition years place women at high risk for visceral obesity as well as osteoporosis. This study was carried out to elucidate the effect of visceral adiposity on ovariectomy-induced osteoporosis in rats. We studied female Wistar rats aged 12-14months, divided into four groups: a) Sham-operated control (SHAM) rats (n=12), rats were fed a control diet (59% of food intake from carbohydrates, 7% from fat, 21% from protein, 13% from minerals and ash) for 12weeks, b) High fat diet-fed control (HFD) group (n=9), rats were fed a high fat diet (49% of food intake from carbohydrates, 17% from fat, 21% from protein, 13% from minerals and ash)for 12weeks, c) Ovariectomized (OVX) rats (n=14), rats were fed a control diet as SHAM rats, d) High fat diet- fed ovariectomized (OVX- HFD) rats (n=13), rats were fed a high fat diet as HFD group. At the end of the experiment, blood samples were collected for calcium, phosphorus, and alkaline phosphatase (ALP) assays. Unilateral left perirenal fats were surgically removed and weighed. Specimens from right perirenal fats and tibia were isolated and processed for histological examination. Histomorphometric analysis of the tibia and visceral adipose tissue was also performed. OVX, HFD, and OVX-HFD rats showed a significant increase in relative visceral fat weight, and plasma ALP, and a significant decrease in plasma calcium, and phosphorus levels compared to SHAM rats. Light microscopic examination of the tibia of the OVX rats revealed a significant decrease in the cortical bone thickness (CBT) and the trabecular bone thickness (TBT), and a significant increase in bone marrow adipose tissue compared to SHAM rats. In addition, there was a significant increase in the osteoclast number, and a significant decrease in the osteoblast number. The changes in bone marrow adipose tissue as well as osteoclast number were further accentuated in OVX-HFD groups. Visceral obesity played a crucial role in the development of osteoporosis in ovariectomized rats through effects that might involve both osteoblasts and osteoclasts.

Serum Immunoglobulins in Children with Vitamin D Resistant Rickets

Background: Vitamin D plays an immunoregulatory role in both the innate and adaptive immune systems. Rickets is a disorder that can develop due to a lack of vitamin D, calcium, or phosphate. Aim: The aim of this study was to assess serum immunoglobulins as one of the aspects of humoral immunity in children with vitamin D resistant rickets. Subjects and Methods: This case-control study was performed on 60 patients divided into Group (A):30 cases with vitamin D resistant rickets patients who were presented with rachitic manifestation who didn’t respond to therapeutic doses of the vitamin. Group (B):30 cases with untreated classic vitamin D deficiency rickets. Group (C): 30 healthy subjects as a control group. All subjects were subjected to detailed history taking including age, sex, weight, dietary history, medication history, and physical examination including vital signs, body weight, and head circumference. Laboratory investigations that included calcium, phosphorus, alkaline phosphatase, electrolytes, ESR, urine analysis, parathyroid hormone, vitamin D, and Immunoglobulin assay. Results: There is a significant decrease of IgA in vitamin D deficiency rickets and vitamin D resistant rickets than in controls (3.74 ± .867, 3.13 ± 1.72, 5.01 ± 1.61, respectively with P =0.012).There is a significant decrease of IgG in vitamin D deficiency rickets and a significant increase in vitamin D resistant rickets than in controls (523.5 ± 136.3, 751.25 ±163.5, 692.0 ± 186.4, respectively with P =0.009). There is no significant difference in IgM in the three studied groups. Conclusion: Patients with vitamin D deficiency have significantly lower IgG levels, while vitamin D resistant patients have significantly higher IgG levels. Whereas, both groups have lower IgA and normal IgM levels.

Pathological femoral neck fracture secondary to Ectopic Parathyroid adenoma located in the Mediastinal Aoroto-Pulmonary window : A Rare Case

Vol 34 | Issue 3 | Sep - Dec 2019 | page: 41-45 | Pulak Sharma, Niraj Ranjan Authors: Pulak Sharma [1], Niraj Ranjan [1] [1] Department of Orthopaedics, APEX TRAUMA CENTER, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, UttarPradesh, India.. Address of Correspondence: Dr. Niraj Ranjan, Department of Orthopaedics, APEX TRAUMA CENTER, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, UttarPradesh, India. E-mail: niraj.ranjan333gmail.com Abstract Primary Hyperparathyroidism (PHPT) has a diverse clinical spectrum which varies from asymptomatic hypercalcaemia to severe metabolic bone disease, pathological fractures and renal stones. Biochemical parameters including serum calcium, phosphorus, alkaline phosphatase (ALP) and PTH assay help in diagnosing PHPT. Ectopic parathyroid adenoma is a rare cause of PHPT. High index of clinical suspicion and a systematic approach is required for its diagnosis and management .Pathological fractures due to ectopic parathyroid adenoma is even rare .We present a case of pathological femoral neck fracture as a result of PHPT due to ectopic parathyroid adenoma situated adjacent to the Aoroto pulmonary window . Stabilization of the fracture once the PTH hormone levels have settled following treatment of hyperparathyroidism are the mainstay in the treatment of this rare clinical entity. Keywords: Femoral Neck , Hyperparathyroidism, Ectopic parathyroid

Crosslinking induces high mineralization of apatite minerals on collagen fibers

Type I collagen, as the critical organic component of bone matrix, plays a template role in mineralization. Gamma-ray irradiation is used to prepare collagen with different crosslinking degrees without introducing foreign substances for mineralization. Significant improvement in crosslinking degree of collagen can be inferred by enzymolysis and differential scanning calorimetry analysis. Scanning electron microscopy observation reveals that, as crosslinking degree increases, the pore structure of collagen becomes more compact. Fourier transform infrared spectroscopy analysis shows the intact retention of classical triple-helical structure of collagen after crosslinking and the following mineralization. Atomic force microscopy characterization, calcium and phosphorus assay kit tests and thermogravimetry measurements indicate that the more compact the collagen structure, the more hydroxyapatite can attach on collagen fibers. These findings reveal the high crosslinking degree of collagen is favorable for the improvement of mineralization ability by providing a more stable and compact network structure. Such crosslinked collagen may provide a more potential way for the preparation of bone substitute materials.

Changes in serum calcium and phosphorus levels and their relationship to egg production in laying hens infected with velogenic Newcastle disease virus

ABSTRACTThis study evaluated the changes that occurred in the serum levels of calcium and phosphorus in laying hens infected with velogenic Newcastle disease (ND) virus (vNDV), and their relationship to the decrease in egg production usually associated with ND. Two hundred and forty laying hens (32 weeks old) were randomly assigned into four groups of 60 each viz: VAI – vaccinated with ND vaccines and intramuscularly inoculated with vNDV, VAU – vaccinated uninfected, UNI – unvaccinated infected and UNU – unvaccinated uninfected. At weekly intervals blood was collected from six randomly selected hens in each group for serum calcium and phosphorus assays. Groups VAI and UNI showed a significant (p < .05) drop in egg production. Serum phosphorus levels of groups VAI and UNI were significantly (p < .05) lower than those of groups VAU and UNU. There was a highly positive correlation between serum phosphorus levels and egg production which was highly significant (r = .74; p < .01). The changes in serum calcium levels of infected groups were only slight, and the relationship between serum calcium levels and egg production was low, positive and not significant (r = .26; p > .05). Drop in egg production that occurred in the ND-infected laying hens was positively strongly correlated with the drop in serum phosphorus levels.

Early prediction of hypocalcemia following thyroid surgery. A prospective randomized clinical trial.

The aim of this randomized-controlled trial was to validate the results of a previous prospective single-cohort observational study conducted in the same surgical unit regarding the use of concomitant intact parathyroid hormone (iPTH) and serum calcium measurement in predicting hypocalcemia after total thyroidectomy. From January 2014 to January 2015, 150 patients underwent total thyroidectomy in our department and were randomized into two groups. The experimental group was submitted to iPTH assay 6h after surgery while the control group was submitted to a daily assay of serum calcium and phosphorus. Sensitivity and specificity of different serum measurements have been calculated using the receiver-operator characteristics (ROC) curve. The prevalence of hypocalcemia was 14.25% in both groups. The assay of iPTH 6h after surgery combined with the serum calcium assay 24h after surgery yielded the highest diagnostic accuracy in predicting hypocalcemia using ROC curves, with 100% sensitivity and 100% specificity. According to our previous study, the combined measurement of iPTH 6h after surgery and of serum calcium 24h after surgery are highly predictive of early postoperative hypocalcemia. These results are important in selecting the patients eligible for early discharge and those who need calcium and vitamin D supplementation.

Elemental composition of Malawian rice.

Widespread potential dietary deficiencies of calcium (Ca), iron (Fe), iodine (I), selenium (Se) and zinc (Zn) have been identified in Malawi. Several deficiencies are likely to be compounded by high phytic acid (PA) consumption. Rice (Oryza sativa) is commonly consumed in some Malawian populations, and its mineral micronutrient content is important for food security. The considerable irrigation requirements and flooded conditions of paddy soils can also introduce or mobilise potentially toxic elements including arsenic (As), cadmium (Cd) and lead (Pb). The aim of this study was to determine the mineral composition of rice sampled from farmers' fields and markets in Malawi. Rice was sampled from 18 extension planning areas across Malawi with 21 white (i.e. polished) and 33 brown samples collected. Elemental composition was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Arsenic speciation was performed using high-performance liquid chromatography (HPLC)-ICP-MS. Concentration of PA was determined using a PA-total phosphorus assay. Median total concentrations (mgkg-1, dry weight) of elements important for human nutrition in brown and white rice, respectively, were: Ca=66.5 and 37.8; Cu=3.65 and 2.49; Fe=22.1 and 7.2; I=0.006 and<0.005; Mg=1130 and 265; Mn=18.2 and 9.6; Se=0.025 and 0.028; and Zn=17.0 and 14.4. In brown and white rice samples, respectively, median PA concentrations were 5438 and 1906mgkg-1, and median PA:Zn molar ratios were 29 and 13. Concentrations of potentially toxic elements (mgkg-1, dry weight) in brown and white rice samples, respectively, were: As=0.030 and 0.006; Cd ≤0.002 and 0.006; Pb=0.008 and 0.008. Approximately 95% of As was found to be inorganic As, where this could be quantified. Malawian rice, like the more widely consumed staple grain maize, contains inadequate Ca, I, Se or Zn to meet dietary requirements. Biofortification strategies could significantly increase Se and Zn concentrations and require further investigation. Concentrations of Fe in rice grain varied greatly, and this was likely due to contamination of rice samples with soil. Risk of As, Cd or Pb toxicity due to rice consumption in Malawi appears to be minimal.

Evaluation of minerals in the seminal plasma of azoospermic semen

Background: Several studies have reported that mineral elements are involved in the performance and maintenance of male fertility.Aim: The aim of present study was to evaluate the mineral elements such as sodium, potassium, calcium, magnesium, phosphorus, chlorine and iron found in the seminal plasma of men was examined at the Pasteur Institute of Ce DIvoire to determine new biochemical markers in azoospermia.Material and Methods: Analysis of seminal fluid was carried out with 30 samples of normozoospermic semen and 30 samples of azoospermic semen. The assay of calcium, phosphorus, magnesium and Iron was done using the automated Hitachi Roche Cobas c 311. The evaluation of the concentration level of chlorine, sodium and potassium in the seminal plasma was performed using the automated 9180 Roche Electrolyte Analyzer. The data collected were analyzed using the software Graph Pad Prism 5. P values less than 0.05 was considered the level of significance.Results: The results of this study showed that the correlation test performed between concentrations level of minerals in the seminal plasma of normozoospermic and azoospermic semen showed no significant difference statistically with P > 0.05.Conclusion: The evaluation of the concentration level of mineral elements such as sodium, potassium, calcium, magnesium, phosphorus, chlorine and iron in the seminal plasma of azoospermic and normozoospermic semen showed that the concentration level of these mineral elements has no diagnostic value in the male reproductive system disorders, including azoospermia.

Quantitative alterations of phospholipids in peripheral blood mononuclear cells in patients with breast and cervical cancer

The aim of this study was to investigate the quantitative changes of absolute and relative amounts of diverse phospholipids in peripheral blood mononuclear cells (PBMCs) in healthy volunteers and patients with breast(BC) and cervical cancer(CC). For this purpose, PLs were analyzed using a lipidomic approach. In brief, PLs were extracted using Bligh and Dyer method, followed by a separation of PL classes by thin layer chromatography, lipid quantification was done using phosphorus assay. In thin-layer chromatography eight fractions of PLs were obtained: lysophosphatidylcholine (LPC), sphingomyelin (SPM), phosphatidylcholine (PC), phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidic acid (PA), diphosphatidylglycerol (DPG). Our results reveal that the all the eight PLs quantified in this study were altered in cancer patient compared to healthy individuals. It is important that the LPC, PC, PE, levels in PBMC membrane of patients with cancer were 2.4, 1.4, 1.3 times higher than those of PBMC membrane of healthy individuals. The PI, PS, PA levels in 1.1, 2.3, 1.3 times lower compared to control group. These quantitative changes in PL components indicate a possible inhibition of signaling pathways in cancer. Notably, these results were identical with those observed chronic lymphoid leukemia studied earlier. Therefore we conclude that quantitative alterations of PLs have been associated to disease and specific PLs may be involved in the onset and evolution of cancer. These data will be useful as a starting point to define possible PLs as prospective biomarkers as well as for discovery of new personalized modes for disease treatment.

Evaluation of the interplay among the charge of porphyrinic photosensitizers, lipid oxidation and photoinactivation efficiency in Escherichia coli

Photodynamic inactivation (PDI) is a simple and controllable method to destroy microorganisms based on the production of reactive oxygen species (ROS) (e.g., free radicals and singlet oxygen), which irreversibly oxidize microorganism’s vital constituents resulting in lethal damage. This process requires the combined action of oxygen, light and a photosensitizer (PS), which absorbs and uses the energy from light to produce ROS. For a better understanding of the photoinactivation process, the knowledge on how some molecular targets are affected by PDI assumes great importance. The aim of this work was to study the relation between the number and position of positive charges on porphyrinic macrocycles and the changes observed on bacterial lipids. For that, five porphyrin derivatives, bearing one to four positive charges, already evaluated as PS on Escherichia coli inactivation, have been tested on lipid extracts from this bacterium, and also on a simple liposome model. The effects were evaluated by the quantification of lipid hydroperoxides and by analysis of the variation of fatty acyl profiles. E. coli suspensions and liposomes were irradiated with white light in the presence of each PS (5.0μM). Afterwards, total E. coli lipids were extracted and quantified by phosphorus assay. Lipid oxidation on bacteria and on liposomes was quantified by ferrous oxidation in xylenol orange (FOX2 assay) and the analysis of the fatty acid profile was done by gas chromatography (GC). As previously observed for E. coli viability, an overall increase in the lipid hydroperoxides content, depending on the PS charge and on its distribution on the macrocycle, was observed. Analysis of the fatty acid profile has shown a decrease of the unsaturated fatty acids, corroborating the relation between lipid oxidation and PDI efficiency. Bacterial membrane phospholipids are important molecular targets of photoinactivation and the number of charges of the PS molecule, as well as their distribution, have a clear effect on the lipid oxidation and on the efficiency of PDI. The distinct extent of the formation of lipid hydroperoxy derivatives, depending on the PS used, is a good indicator of this process. The FOX2 assay allowed the detection of lipid peroxidation of E. coli membrane after PDI with all the five porphyrins, however, it was not the most appropriated method to quantify the relative lipid oxidation caused by PS with different efficiencies. The fatty acid analysis used to quantify the extent of lipid oxidation by the different PS provided better results. The same results were observed for the liposome model. Consequently, the model system based on liposomes is a fast and simple method that can be used for the screening of the efficiency of new PS, before proceeding with the more complex studies on bacterial models.

Long-chain Acyl-CoA Dehydrogenase Deficiency as a Cause of Pulmonary Surfactant Dysfunction

Long-chain acyl-CoA dehydrogenase (LCAD) is a mitochondrial fatty acid oxidation enzyme whose expression in humans is low or absent in organs known to utilize fatty acids for energy such as heart, muscle, and liver. This study demonstrates localization of LCAD to human alveolar type II pneumocytes, which synthesize and secrete pulmonary surfactant. The physiological role of LCAD and the fatty acid oxidation pathway in lung was subsequently studied using LCAD knock-out mice. Lung fatty acid oxidation was reduced in LCAD(-/-) mice. LCAD(-/-) mice demonstrated reduced pulmonary compliance, but histological examination of lung tissue revealed no obvious signs of inflammation or pathology. The changes in lung mechanics were found to be due to pulmonary surfactant dysfunction. Large aggregate surfactant isolated from LCAD(-/-) mouse lavage fluid had significantly reduced phospholipid content as well as alterations in the acyl chain composition of phosphatidylcholine and phosphatidylglycerol. LCAD(-/-) surfactant demonstrated functional abnormalities when subjected to dynamic compression-expansion cycling on a constrained drop surfactometer. Serum albumin, which has been shown to degrade and inactivate pulmonary surfactant, was significantly increased in LCAD(-/-) lavage fluid, suggesting increased epithelial permeability. Finally, we identified two cases of sudden unexplained infant death where no lung LCAD antigen was detectable. Both infants were homozygous for an amino acid changing polymorphism (K333Q). These findings for the first time identify the fatty acid oxidation pathway and LCAD in particular as factors contributing to the pathophysiology of pulmonary disease.

Analysis of follicular fluid total phospholipids in women undergoing in-vitro fertilisation

Follicular fluid (FF) samples were obtained from 100 patients referred to the University Hospital. A total of 79 subjects underwent IVF and the remaining 21 underwent ICSI. The levels of apoA-I and total phospholipid were measured using turbidometric and colorimetric phosphorus assays, respectively. Correlation analysis showed a significant inverse association of total phospholipid in FF with fertilisation ratio (r = –0.24, p = 0.04). Furthermore, the ratio of phospholipid/apoA-I in patients with a percentage of fertilised oocytes ≤ 50% was significantly higher (> 2.5%, p < 0.05) than in those with higher percentages of fertilised oocytes. The amounts of phospholipid and phospholipid/apoA-I ratio in FF were associated negatively to the percentage of oocyte fertilisation. Therefore, the change in the phospholipid and phospholipid/apoA-I ratio of FF might be regarded as indicators of female fertility.