New biograft solution, growth factors and bone regenerative approaches in neurosurgery, dentistry, and orthopedics: a review.

Bone regeneration following surgery, trauma, or any other condition is an autologous process that can fail, necessitating the requirement of novel procedures and materials. Recently, significant progress has been made in the research related to regenerative medicine. At the same time, biomedical implants in spine surgery, orthopedics, and dentistry are facing many challenges and posing clinical concerns. A PubMed, MEDLINE, and Scopus review was carried out to identify all studies dealing with bone regenerative approaches in dentistry, orthopedics, and neurosurgery from database inception to December 2022. There has been an upsurge in the implication of a multitude of materials in the enhancement of bone regeneration and/or neo-bone formation, including blood-derived growth factors, new biografts, biosynthetic polymers, inorganic compounds, and sea corals, in the very recent years. Stem cells (SCs) have been found to be efficacious and safe modalities in osteogenesis. Furthermore, bone regeneration/formation depends on the host's immune system and metabolic condition. Epidermal growth factors (EGFs) and their receptors (EGFRs) are important in the mechanism of wound repairing and healing through the recruitment of stromal stem cells for epidermal and dermal regeneration. Similarly, biocomposite developed from Silica assembled with calcium and phosphorous has been utilized in the treatment of broken bones. In this review, we summarized the clinical and laboratory evidence of bone regenerative approaches in the field of spine surgery, orthopedics, and dentistry. An accurate pre-operative screening is the key to managing and carefully planning all surgical steps and achieving the final success.

Assessment of wastewater-borne pharmaceuticals in tissues and body fluids from riverine fish.

Riverine fish in densely populated areas is constantly exposed to wastewater-borne contaminants from effluent discharges. These can enter the organism through the skin, gills or by ingestion. Whereas most studies assessing the contaminant burden in exposed fish have focused either on muscle or a limited set of tissues. Here we set out to generate a more comprehensive overview of the distribution of pollutants across tissues by analyzing a panel of matrices including liver, kidney, skin, brain, muscle, heart, plasma and bile. To achieve a broad analyte coverage with a minimal bias towards a specific contaminant class, sample extracts from four fish species were analyzed by High-Performance Liquid Chromatography (HPLC) - high-resolution mass spectrometry (HRMS) for the presence of 600 wastewater-borne pharmaceutically active compounds (PhACs) with known environmental relevance in river water through a suspect-screening analysis. A total of 30 compounds were detected by suspect screening in at least one of the analyzed tissues with a clear prevalence of antidepressants. Of these, 15 were detected at confidence level 2.a (Schymanski scale), and 15 were detected at confidence level 1 following confirmation with authentic standards, which furthermore enabled their quantification. The detected PhACs confirmed with level 1 of confidence included acridone, acetaminophen, caffeine, clarithromycin, codeine, diazepam, diltiazem, fluoxetine, ketoprofen, loratadine, metoprolol, sertraline, sotalol, trimethoprim, and venlafaxine. Among these substances, sertraline stood out as it displayed the highest detection frequency. The values of tissue partition coefficients for sertraline in the liver, kidney, brain and muscle were correlated with its physicochemical properties. Based on inter-matrix comparison of detection frequencies, liver, kidney, skin and heart should be included in the biomonitoring studies of PhACs in riverine fish.

Development of a USE/d-SPE and targeted DIA-Orbitrap-MS acquisition methodology for the analysis of wastewater-derived organic pollutants in fish tissues and body fluids.

Pharmaceuticals (PhACs) are partially removed during wastewater treatment and end up in the receiving waters. As a result, aquatic biota is continuously exposed to a wide range of potentially hazardous contaminants such as PhACs. Therefore, fish could be a good bio indicator to give a direct measure of the occurrence of PhACs in the aquatic environment. In this study, a robust analytical method has been optimized and validated for the determination of 81 organic compounds, mainly PhACs, in seven wild fish tissue types (liver, muscle, pancreas, kidney, skin, heart, and brain) and two body fluids (plasma and bile). Solid samples extraction was performed combining a procedure based on bead beating tissue homogenization plus ultrasound extraction followed by dispersive solid-phase extraction (dSPE) clean-up using zirconia and C18 sorbents for solid matrices, whereas bile and plasma were diluted. The key aspects of this method are: • The method facilitated the simultaneous extraction of 81 PhACs of a wide range of polarity (logP from -4.9 to 5.6) in tissues with variable lipid content. • The validation was performed using Cyprinus carpio at 20 ng g-1 and 200 ng g-1 for solid tissues, 50 ng mL-1 and 500 ng mL-1 for plasma, and 100 ng mL-1 and 1000 ng mL-1 for bile. Analyte detection was performed in LC-HRMS Q-Exactive Orbitrap system with full scan and targeted data-independent acquisition (DIA) mode for high-confidence and sensitive quantitation in either (+) or (-) ESI mode. • The majority of compounds presented recoveries between 40% and 70% and relative standard deviations (RSD) below 30%.

One-step extraction and analysis of 45 contaminants of emerging concern using QuEChERS methodology and HR-MS in radish leaves and roots.

The scarcity of freshwater has led to a considerable increase of the reuse of reclaimed wastewater for irrigation of field crops [1,2]. This practice potentially exposes agricultural produce to a large variety of xenobiotic compounds including contaminants of emerging concern (CECs) which have been widely recognized to be present in wastewater [3]. Common approaches for the extraction of CECs from crops rely on solid-liquid extraction [4], assisted solvent extraction [5], ultra-sound solvent extraction [6] and recently QuEChERS (QUick, Easy, CHeap, Effective, Rugged and Safe) [[7], [8]-9]. Here, eight QuEChERS-based methodologies were compared for their suitability to determine 45 CECs in roots and leaves of soil-grown radish. The key points of the method development were:•The development of two single-step analytical methods specific for radish root and leaves, after testing eight different approaches using QuEChERS extraction for the quantitation of 45 CECs. The analytical methodology selected requires minimal time and solvent, making it cost-effective.•Methods validation were performed at five concentrations levels (2, 5, 10, 50 and 200 ng g-1), with low limits of quantification between 0.01 and 0.32 ng g-1.•The two optimized methodologies may be applied to identify large number of compounds of different families in radish crop. However, validation will be needed to quantify compounds different from the target compounds of this paper.

Insights into the removal of pharmaceutically active compounds from sewage sludge by two-stage mesophilic anaerobic digestion.

The removal efficiencies (REs) of twenty-seven pharmaceutically active compounds (PhACs) (eight analgesic/anti-inflammatories, six antibiotics, four ß-blockers, two antihypertensives/diuretics, three lipid regulators and four psychiatric drugs) were evaluated in a pilot-scale two-stage mesophilic anaerobic digestion (MAD) system treating thickened sewage sludge from a pilot-scale A2O™ wastewater treatment plant (WWTP) which was fed with wastewater from the pre-treatment of the full-scale WWTP Murcia Este (Murcia, Spain). The MAD system was long-term operated using two different sets of sludge retention times (SRTs) for the acidogenic (AcD) and methanogenic (MD) digesters (phase I, 2 and 12 days; and phase II, 5 and 24 days, in AcD and MD, respectively). Quantitative PCR (qPCR) and Illumina MiSeq sequencing were used to estimate the absolute abundance of Bacteria, Archaea, and Fungi and investigate the structure, diversity and population dynamics of their communities in the AcD and MD effluents. The extension of the SRT from 12 (phase I) to 24 days (phase II) in the MD was significantly linked with an improved removal of carbamazepine, clarithromycin, codeine, gemfibrozil, ibuprofen, lorazepam, and propranolol. The absolute abundances of total Bacteria and Archaea were higher in the MD regardless of the phase, while the diversity of bacterial and archaeal communities was lower in phase II, in both digesters. Non-metric multidimensional scaling (MDS) plots showed strong negative correlations among phyla Proteobacteria and Firmicutes and between genera Methanosaeta and Methanosarcina throughout the full experimental period. Strong positive correlations were revealed between the relative abundances of Methanospirillum and Methanoculleus and the methanogenesis performance parameters (volatile solids removal, CH4 recovery rate and %CH4 in the biogas), which were also related to longer SRT. The REs of several PhACs (naproxen, ketoprofen, ofloxacin, fenofibrate, trimethoprim, and atenolol) correlated positively (r > 0.75) with the relative abundances of specific bacterial and archaeal groups, suggesting their participation in biodegradation/biotransformation pathways.

Biomarker responses and metabolism in Lumbricus terrestris exposed to drugs of environmental concern, an in vivo and in vitro approach.

The earthworm Lumbricus terrestris is an anecic species living in natural soils but it is also a sentinel in pollution monitoring. Specimens of L.terrestris were exposed for 48 h though the filter paper contact test at 1 mg/mL of the chemicals: Lamotrigine (LMG), Cocaine (COC), Fipronil (FIP) and the pesticide bis-4-nitrophenyl phosphate (BNPP). After that period, the activities of Acetylcholinesterase, Glutathione S-transferase, Carboxylesterase (CE) using different substrates, and lipid peroxidation levels were evaluated in the exposed whole tissue earthworms. The results revealed differences only in CE activity, with 4-nitrophenyl butyrate (4NPB) and 1-naphthyl butyrate (1NB) the most responsive substrates to COC. The kinetic parameters of CE were characterized, for the first time, in whole tissue of this species. The chemical analysis by LC-MS/MS, confirmed the exposure to the parent compounds, identified metabolites and evidenced biotransformation pathways in earthworms. Metabolic reactions included oxidation (LMG and FIP), hydrolysis (COC and FIP) as well as glycosylation (LMG, COC and FIP). A hitherto unknown metabolite of LMG due to the conjugation with phenylalanine glutamine was formed. The in vivo results on CE activity with the specific inhibitor, BNPP, were confirmed in vitro. Moreover, in the in vitro approach, the inclusion of other contaminants of environmental concern supports the potential of CE as biomarker. This study identifies the main metabolites formed by earthworms for further in vivo exposures under more realistic conditions and the potential use of CE measures as biomarker of emerging contaminants.

Removal and toxicity evaluation of a diverse group of drugs from water by a cyclodextrin polymer/pulsed light system.

The presence of pharmaceutical compounds (PhCs) in the effluents of wastewater treatment plants (WWTPs) is an ecological concern. The issue could be alleviated by trapping those substances by cyclodextrin (CD) polymers or photolyzing them by pulsed light (PL). Consequently, a sequential CD polymer/PL system was tested for the removal of PhCs. Firstly, a survey detected the presence of recurrent PhCs in the effluents of local WWTPs. Then, pure water was spiked with 21 PhCs, 100 µg/L each one. The three-dimensional network provides amphiphilic features to the CD polymer that reduced the pollutant concentration by 77 %. Sorption involves a plead of physical and chemical mechanisms hindering the establishment of a general removal model for all compounds. The performed simulations hint that the retention capacity mainly correlates with the computed binding energies, so that theoretical models are revealed as valuable tools for further improvements. The complementary action of PL rose the elimination to 91 %. The polymer can be reused at least 10 times for ibuprofen (model compound) removal, and was able to eliminate the ecotoxicity of an ibuprofen solution. Therefore, this novel sequential CD polymer/PL process seems to be an efficient alternative to eliminate PhCs from wastewater.

Analysis of pharmaceuticals in fish using ultrasound extraction and dispersive spe clean-up on que Z-Sep/C18 followed by LC-QToF-MS detection.

The presence of pharmaceutically active compounds (PhACs) in aquatic biota has been received much less attention than their presence in surface or waste water, and it was not until the mid-2000s, this gap started to be addressed. Here, we present SQUEEZe (Solid-liQuid Ultrasound Extraction with QuE Z-Sep/C18 as dispersive clean-up): a fast method for analysis of the trace 47 PhACs in fish muscle. Compared to our previously reported method [1], it offers alternatives with improvements in recoveries, number of analytes, sample volume and solvent used. The key aspects of this method are:•The ultrasound extraction was performed with acetonitrile/isopropanol 0.1% V/V formic acid. A clean-up step using QuE Z-Sep/C18 sorbents was employed to reduce lipid content of the extracts and further matrix effects in the detection of the analytes.•A HPLC separation with a Kinetex EVO C18 packed column in 11 min was optimized. MS and MS/MS data were collected using SWATH acquisition on the SCIEX X500R QTOF in (+)-ESI mode.•The method validated at 3 different concentrations levels: 5, 25 and 50 ng/g fish. It presented good intraday/interday reproducibility and absolute recoveries ≥ 60% for majority of analytes in composite homogenate muscle matrix of Squalius cephalus.•10 out 47 compounds were detected in fish samples.

Combining quantitative and qualitative approaches using Sequential Window Acquisition of All Theoretical Fragment-Ion methodology for the detection of pharmaceuticals and related compounds in river fish extracted using a sample miniaturized method.

A fast method for analysis of 47 pharmaceuticals active compounds (PhACs) in fish muscle has been developed and validated addressing the parameters accuracy, precision (intraday and interday), matrix effect at three spiking levels: 5, 25 and 50 ng PhAC g-1 in fish as well as linearity, limit of detection (LOD), limit of quantification (LOQ). Sixteen protocols were performed varying extraction techniques, solvents, sample filtration and clean-up step. The selected method was based on an ultrasound extraction with acidified mixture of acetonitrile and isopropyl alcohol followed by a clean-up step using Z-Sep/C18 sorbents. Quantitative analysis of the PhACs in the extracts was accomplished by UPLC- QTOF-MS using Sequential Window Acquisition of All Theoretical Fragment-Ion, SWATHTM acquisition technology. 90% Of the compounds presented extraction recoveries between 60 and 130% with LOQ between 0.2 and 11 ng g-1. The validated method was applied to the analysis of 32 muscle samples from thirteen different species of fish collected in four European river basins (Adige, Evrotas, Llobregat and Sava). A total of ten compounds were found in fish samples with diltiazem as the most frequently detected one followed by carbamazepine and caffeine. Additionally, by taking advantage of the information-rich mass spectral data from the SWATH mode acquisition, the raw data were reprocessed for the presence of the most prescribed 250 pharmaceuticals, metabolites, and drugs of abuse previously reported to occur in the aquatic environment. By considering the mass errors of the molecular ion (˂± 3 ppm) and one characteristic fragment ion (˂±10 ppm) as well as the Library score and the Formula Finder score of the data processing software six compounds were retrieved, and eventually four of them confirmed with authentic standards: cocaine and its metabolite benzoylecgonine, the stimulant nicotine, and the antibiotic ofloxacin. Two lipid regulators, lovastatin and simvastatin, were determined as a false positive.

Linking microbial diversity and population dynamics to the removal efficiency of pharmaceutically active compounds (PhACs) in an anaerobic/anoxic/aerobic (A2O) system.

The removal efficiencies (REs) of nineteen pharmaceutically active compounds (PhACs) (six antibiotics-clarithromycin, ofloxacin, sulfadiazine, sulfamethazine, sulfamethoxazole and trimethoprim -, four ß-blockers -atenolol, metoprolol, propranolol and sotalol-, two antihypertensives/diuretics -furosemide and hydrochlorothiazide-, three lipid regulators -bezafibrate, fenofibrate and gemfibrozil-, and four psychiatric medications -carbamazepine, diazepam, lorazepam and paroxetine) were ascertained in a pilot-scale anaerobic/anoxic/aerobic (A2O) system treating urban wastewater, long term operated during two experimental phases using different sets of environmental conditions and operating parameters. Illumina MiSeq sequencing was used to investigate the structure, diversity and population dynamics of bacteria, archaea and fungi communities in the activated sludge. The results showed that mixed liquor suspended solids (MLSS) and food-to-microorganisms ratio (F/M) were operational parameters significantly influencing the REs of five of the analyzed PhACs in the A2O system. Biota-environment (BIO-ENV) analysis revealed strong correlations between population shifts of the activated sludge community and the REs of PhACs of the different pharmaceutical families. Increased REs of clarithromycin, furosemide, bezafibrate and gemfibrozil were concomitant to higher relative abundances of bacterial phylotypes classified within the Rhodobacteraceae and Sphingomonadaceae (Alphaproteobacteria), while those of Betaproteobacteria, Chloroflexi and Methanomethylovorans (Euryarchaea) correlated positively with the REs of up to seven PhACs belonging to different therapeutic groups.

Polluted water from an urban reservoir (Madín dam, México) induces toxicity and oxidative stress in Cyprinus carpio embryos.

The Madín Dam is a reservoir located in the municipalities of Naucalpan and Atizapán, in the metropolitan area adjacent to Mexico City. The reservoir supplies drinking water to nearby communities and provides an area for various recreational activities, including kayaking, sailing and carp fishing. Over time, the number of specimens of common carp has notably diminished in the reservoir, which receives direct domestic drainage from two towns as well as numerous neighborhoods along the Tlalnepantla River. Diverse studies have demonstrated that the pollutants in the water of the reservoir produce oxidative stress, genotoxicity and cytotoxicity in juvenile Cyprinus carpio, possibly explaining the reduction in the population of this species; however, it is necessary to assess whether these effects may also be occurring directly in the embryos. Hence, surface water samples were taken at five sites and pharmaceutical drugs, personal care products (especially sunscreens), organophosphate and organochlorine pesticides, and other persistent organic pollutants (e.g., polychlorinated biphenyls and polycyclic aromatic hydrocarbons) were identified. Embryos of C. carpio were exposed to the water samples to evaluate embryolethality, modifications in embryonic development, lipoperoxidation, the quantity of hydroperoxide and oxidized proteins, and antioxidant enzyme activity (superoxide dismutase, catalase and glutathione peroxidase). It was found that the polluted water of the Madín Dam gave rise to embryolethality, embryotoxicity, congenital abnormalities, and oxidative stress on the common carp embryos.

Development and validation of an analytical method for determination of pharmaceuticals in fish muscle based on QuEChERS extraction and SWATH acquisition using LC-QTOF-MS/MS system.

This study aimed at developing an analytical method for the extraction and quantification of 21 pharmaceutical actives compounds (PhACs) present in fish muscle. Using Norwegian Atlantic salmon as matrix, two extraction methods for PhACs were tested: ultrasound extraction (USE) using methanol (MeOH), acetonitrile (MeCN) or a mixture of MeCN:MeOH (1:1, v/v) as extracting solvents, and QuEChERS method using three different extraction salts. After selecting QuEChERS Original as extracting method of the analytes, three different clean-up methods were evaluated with respect to their efficiency to remove coextracted fat and lipids such as Enhanced Matrix Removal (EMR) and HLB prime. The dispersive-SPE EMR yielded the best recoveries for 21 of 27 analytes. PhACs were quantified by UPLC-MS/MS using SWATH acquisition mode. The method was validated in terms of recoveries, accuracy, linearity, precision, matrix effects at three levels of concentration: 25, 200 and 500 ng g-1 dw of fish muscle. For the majority of the analytes the recoveries were over 70%. Finally, the validated method was applied to natural riverine fish from the Evrotas river (Greece) and the Adige river (Italy) with positive findings for acetaminophen, propranolol, and venlafaxine reaching concentrations as high as 80 ng g-1 of muscle.

Volatile metabolites, quality and sensory parameters of "Ferrovia" sweet cherry cold stored in air or packed in high CO2 modified atmospheres.

Volatile organic compounds, quality and sensory attributes of sweet cherry cv "Ferrovia", cold packaged in Air or in different modified atmospheres (Low-O2 = 1% O2/0.03% CO2; High-CO2 = 16% O2/20% CO2; Mix = 1% O2/20% CO2), were monitored until 21 days of conservation. Results showed that sweet cherry cv "Ferrovia" is sensitive to CO2 accumulation (over 20%) in low oxygen (about 1%) modified atmosphere, as showed by the increase in respiration rate, biosynthesis of fermentative volatile metabolites, and sensory perception of off-odours. However, High-CO2 treatment seemed to preserve quality and sensory traits, presumably due to the high initial concentration of O2 (16%) that could limit the synthesis of ethyl esters and γ-butyrolactone, keeping the accumulation of off-flavours below their sensory perception threshold. Finally, PLSR analysis allowed to select 1-pentanol as putative marker of sensory alteration and hexanal and 2-hexenal as possible predictors of freshness for "Ferrovia" sweet cherries.

Effects of residual disinfectant on soil and lettuce crop irrigated with chlorinated water.

The accidental or continuous release of residual chlorine in water reclaimed for irrigational purposes could compromise the crop yield and increase the load of toxic organo-halogenated compounds, posing additional risks for environment and human health. This study was aimed at assessing the consequences of using chlorinated water for irrigating lettuce crops grown in pots with two different types of soil. The results show that the accumulation of extractable organo-halogenated compounds (EOX) in soil, roots and leaves is directly related to the chlorine concentration in the irrigation water. The accumulation of EOX in sandy soils is not significant, while it reached up to 300% of the control in the silty-clay soil, demonstrating that the phenomenon is linked to the organic matter content in the soil. The accumulation of EOX in the soil appears to play a significant role in subsequent bioaccumulation in cultures irrigated with tap water (long term memory effect). Chloramines also demonstrated to have similar impacts as the free chlorine from hypochlorite. The consistent bioaccumulation of 400-700µgClkg-1 of EOX in the leaves of crops irrigated with just 0.2mgClL-1 of residual chlorine, as compared to levels below the detection limit of 75µgClkg-1 in the control crops, evidences the potential impact on food chain and human health.

Persistence of fenitrothion in oranges and clementines after treatment with emulsifiable concentrate and microencapsulate formulations.

The rate of decline of fenitrothion residues was investigated in oranges and clementines after treatment with two different kinds of commercial formulations: emulsifiable concentrate (Afidina M) and microencapsulate (Fenitrocap and IPM 400). The study was performed on the fruit and leaves over 131 and 161 days for oranges, and over 78 and 86 days for clementines, respectively. In fruit, the experimental data showed a similar behaviour of the active ingredient for both kinds of commercial formulations. High mean levels of fenitrothion (between about 0.4 and 0.8 mg kg(-1)) were persistent for at least 75 days after treatment in oranges and 50 days in clementines, with statistically significant declines observed only at days 110 and 78, respectively. A rapid decline of fenitrothion levels was observed in orange and clementine leaves during the starting phase followed by a slower decrease during the later stage; the decline was more pronounced with the treatment of emulsifiable concentrates. These findings are indicative of a poor degradability of fenitrothion in citrus fruits, and suggest that repeated or uneven applications of the pesticide should be avoided in order to exclude the risk of exceeding the maximum residue level permitted by the current regulations.

Effects of omeprazole therapy on peptic disease and serum gastrin levels in hemodialysis patients. A preliminary study.

Hemodialysis patients are frequently affected by peptic disease, and in many cases they have high serum levels of gastrin. The aim of this study was to evaluate the effects of omeprazole, an inhibitor of gastric parietal cells hydrogen pump, on peptic disease and gastric secretion of 16 selected dialysis patients. H2-receptors blocking drugs or gastric acidity buffers were withdrawn for 2 weeks, then omeprazole was administered for 4 weeks at a daily dosage of 20 mg. Before and after the omeprazole therapy, registration of subjective peptic symptoms, baseline serum gastrin dosage and endoscopy of upper digestive tract were performed. Before starting omeprazole, the serum gastrin value was 515 +/- 180 pg/l, all the patients complained of peptic symptoms, and endoscopy showed: 8 cases of duodenal ulcer, 3 cases of pyloric ulcer and 5 cases of antral erosive gastritis. At the end of the omeprazole treatment period, a slight but statistically not significant increase of serum gastrin level (537 +/- 198 pg/l) was observed. Twelve patients reported the total disappearance of symptoms of peptic disease, 3 patients a partial reduction, and 1 patient had no improvement. Control endoscopy showed the healing (white scar) of all the ulcers, and the disappearance of all the erosive lesions. In conclusion, our results show that a 20 mg/day omeprazole short-term therapy can be given safely to uremic patients undergoing hemodialysis and is effective for a quick healing of active peptic lesions.

Combined dialysis and plasma-exchange in acute renal failure.

Combined use of plasma-exchange and dialysis therapy in 3 different cases of acute renal failure is presented. The first is a case of acute renal failure due to rhabdomyolysis caused by hemlock poisoning. Plasma-exchange was effective in improving the signs of rhabdomyolysis and renal failure. The second is a case of acute renal failure in an IgG-kappa myeloma. After 9 sessions of plasma-exchange, performed simultaneously with CAPD, a significant fall in the plasma and urine light chains levels was obtained. After the recovery of normal renal function, CAPD was prosecuted to remove light chains. The last is a case of acute renal failure in a patient with a mesangiocapillary nephritis and a high level of circulating immune complexes (CIC). He underwent steroid therapy and daily sessions of hemodialysis, followed by plasma-exchange, which permitted a fall of the CIC level, until a normal renal function was achieved. In conclusion, plasma-exchange combined with dialysis, is an useful tool for the management of acute renal failure caused by toxic proteins.

Confirmation of high prevalence of hepatitis C antibodies in hemodialysis patients by second generation immunoblot assay.

Sera from 209 dialysis patients were tested for antibodies to hepatitis C virus (anti-HCV) by a 2nd generation enzyme-linked immunoassay (ELISA 2) using nonstructural and core antigens. Confirmation of reactivity was obtained by a 2nd generation immunoblot assay (RIBA 2) for antibodies to 4 separate antigens (5-1-1, c100-3, c33c, c22-3). ELISA 2 was positive in 99 sera, 95 of which were confirmed by RIBA 2, thus accounting for an anti-HCV prevalence of 45.5%. Anti-HCV positivity was correlated to longer duration of dialysis therapy (p less than 0.001), higher number of transfusions (p less than 0.001), history of kidney transplant (p less than 0.001) and of serum alanine/aspartate aminotransferase (AST/ALT; p less than 0.001) or gamma-glutamyltransferase (GGT) (p less than 0.001) increments. The most frequent RIBA 2 patterns were: reactivity to all 4 antigens (34 patients) and to c33c and c22-3 (45 patients). The former patients, compared to the latter, had higher values of AST (p less than 0.08), ALT (p less than 0.02), GGT (p less than 0.005), IgG (p less than 0.05). It is possible that the reactivity to all 4 antigens of RIBA 2 is a clue of a greater activity of viral hepatic disease.

L-ascorbatemia during biofiltration.

In a study of the intradialytic behaviour of l-ascorbatemia during acetate and bicarbonate dialysis we noted the paradoxical increase in l-ascorbatemia during the first hour of acetate dialysis. During biofiltration, the intradialytic curve of l-ascorbatemia is similar to that in bicarbonate dialysis, even though an acetate dialysis bath is used. Thus the paradoxical rise of l-ascorbatemia during acetate dialysis may be due to the relative acidosis of the first hour.