Phytoconstituent analysis, anti-inflammatory, antimicrobial and anticancer effects of nano encapsulated Convolvulus arvensis L. extracts.

BACKGROUND: The Convolvulus genus is distributed all over the world and has a long history in traditional medicine. As nanotechnology expands its reach into areas like drug delivery and biomedicine, this study intends to assess the potential of Convolvulus arvensis L. extracts as anti-bacterial, anti-inflammatory and anti-cancer agents, along with chemical profiling of the methanolic (MeOH) extract active ingredients. METHODS: The chemical composition of an 85% MeOH extract was investigated by liquid chromatography with an electrospray source connected to mass spectrometry (LC-ESI-MS). Both the 85% MeOH extract and n-butanol fraction of C. arvensis were loaded for the first time on alginate/chitosan nanoparticles. The 85% MeOH extract, n-butanol fraction and their loaded nanoparticles were tested for their cytotoxicity, anticancer, anti-inflammatory and antibacterial activity (against pathogenic bacteria, E. coli and S. aureus). RESULTS: The chemical investigation of 85% MeOH extract of C. arvensis underwent LC-ESI-MS analysis, revealing twenty-six phenolic substances, of which 16 were phenolic acids, 6 were flavonoids, 1 glycolipid, 1 sesquiterpene and 2 unknown compounds. The FT-IR spectra confirmed the encapsulation of the 85% MeOH extract and n-butanol fraction onto alginate/chitosan nanoparticles and small size obtained by TEM maintained them nontoxic and enhanced their anti-inflammatory activity (the IC50 was decreased from 1050 to 175 µg/ml). The anti-cancer activity against HepG2 was increased and the cell viability was decreased from 28.59 ± 0.52 to 20.80 ± 0.27 at a maximum concentration of 1000 µg/ml. In addition, the MIC of encapsulated extracts was decreased from 31.25 to7.78 µg/ml in E. coli (Gm-ve) and from 15.56 to 7.78 µg/ml in S. aureus (Gm + ve) bacteria. CONCLUSION: Both alginate and chitosan are excellent natural polymers for the encapsulation process, which affects positively on the bioactive constituents of C. arvensis extracts and improves their biological properties.

A novel antibacterial approach of Cecropin-B peptide loaded on chitosan nanoparticles against MDR Klebsiella pneumoniae isolates.

Egypt has witnessed the emergence of multidrug-resistant (MDR) Klebsiella pneumoniae, which has posed a serious healthcare challenge. The proper treatment choice for MDR-KP infections is not well determined which renders the problem more complicated, thus making the control of such infections a serious challenge for healthcare professionals. This study aims to encapsulate the cationic antimicrobial peptide; Cecropin-B (Cec-B), to increase its lifetime, drug targeting, and efficacy and study the antimicrobial effect of free and encapsulated recombinant rCec-B peptide on multidrug-resistant K. pneumoniae (MDR-KP) isolates. Fifty isolates were collected from different clinical departments at Theodore Bilharz Research Institute. Minimal inhibitory concentrations (MICs) of rCec-B against MDR-KP isolates were determined by the broth microdilution test. In addition, encapsulation of rCec-B peptide into chitosan nanoparticles and studying its bactericidal effect against MDR-KP isolates were also performed. The relative expression of efflux pump and porin coding genes (ArcrB, TolC, mtdK, and Ompk35) was detected by quantitative PCR in treated MDR-KP bacterial isolates compared to untreated isolates. Out of 60 clinical MDR isolates, 50 were MDR-KP. 60% of the isolates were XDR while 40% were MDR. rCec-B were bactericidal on 21 isolates, then these isolates were subjected to treatment using free nanocapsule in addition to the encapsulated peptide. Free capsules showed a mild cytotoxic effect on MDR-KP at the highest concentration. MIC of encapsulated rCec-B was higher than the free peptide. The expression level of genes encoding efflux and porin (ArcrB, TolC, mtdK, and Ompk35) was downregulated after treatment with encapsulated rCec-B. These findings indicate that encapsulated rCec-B is a promising candidate with potent antibacterial activities against drug-resistant K. pneumoniae.

Synthesis, characterization, and cytotoxicity of doxorubicin-loaded polycaprolactone nanocapsules as controlled anti-hepatocellular carcinoma drug release system.

BACKGROUND: Free doxorubicin (Dox) is used as a chemotherapeutic agent against hepatocellular carcinoma (HCC), but it results in cardiotoxicty as a major side effect. Hence, a controlled Dox drug delivery system is extremely demanded. METHODS: Dox was loaded into the non-toxic biodegradable polycaprolactone (PCL) nanocapsules using the double emulsion method. Characterization of Dox-PCL nanocapsules was done using transmission electron microscopy and dynamic light scattering. Encapsulation efficiency and drug loading capacity were quantified using UV-visible spectrophotometry. Drug release was investigated in vitro at both normal (7.4) and cancer (4.8) pHs. Cytotoxicity of Dox-PCL nanocapsules against free Dox was evaluated using the MTT test on normal (Vero) and hepatic cancer (HepG2) cell lines. RESULTS: Spherical nanocapsules (212 ± 2 nm) were succeffully prepared with a zeta potential of (-22.3 ± 2 mv) and a polydisperse index of (0.019 ± 0.01) with a narrow size distribution pattern. The encapsulation efficiency was (73.15 ± 4%) with a drug loading capacity of (16.88 ± 2%). Importantlly, Dox-release from nanocapsules was faster at cancer pH (98%) than at physiological pH (26%). Moreover, although Dox-PCL nanocapsules were less toxic on the normal cell line (GI 50 = 17.99 ± 8.62 µg/ml) than free Dox (GI 50 = 16.53 ± 1.06 µg/ml), the encapsulated Dox showed higher toxic effect on cancer HepG2 cells compared to that caused by the free drug (GI 50 = 2.46 ± 0.49 and 4.22 ± 0.04 µg/ml, respectively). CONCLUSION: The constructed Dox-PCL nanocapsules constitute a potentially controlled anti-HCC therapy with minimal systemic exposure.

Detection of Occult Hepatitis C Virus Infection in Egyptian Patients Who Achieved a Sustained Virologic Response to Direct-Acting Antiviral Agents.

BACKGROUND: Occult hepatitis C virus (HCV) infection (OCI) is diagnosed based on the detection of HCV-RNA in non-serum reservoirs, such as peripheral blood mononuclear cells (PBMCs) and/or hepatocytes with undetectable HCV-RNA in the serum. The current study was designed to shed more light on the presence of occult HCV in a population of cases who achieved an SVR after receiving treatments for HCV-infection and its significance. METHODS: This cross-sectional study evaluated 111 chronic HCV patients treated at Theodor Bilharz Research Institute, Egypt and achieved a sustained virological response (SVR) 12 -24 weeks after treatment with Direct acting antiviral drugs (DAAs). The treatment lasted 12 or 24 weeks using generic medications including Sofosbuvir (SOF) 400 mg/day and Daclatasvir (DCV) 60 mg/day ± weight-based Ribavirin (RBV) 600-1000 mg/day. After achieving the SVR 12 -24 weeks, all patients were subjected to clinical examination and full laboratory investigations. All the candidates were assessed for fibrosis pre/post-treatment by transient elastography (Fibroscan©). Eighty-seven patients (78.4%) received dual therapy (SOF/DCV) and 24 patients (21.6%) received triple therapy (SOF/DCV/RBV). One hundred and seven patients received the regimen for 12 weeks (96.4%) and only four patients received the regimen for 24 weeks (3.6%). All patients were examined in terms of HCV RNA in plasma and PBMCs. RESULTS: Nine patients (8.1%) were positive for PBMCs HCV RNA. The presence of Occult HCV infection (OCI) was significantly correlated with age, level of AFP, and the degree of liver stiffness. CONCLUSION: The OCI was present in 8.1% of the patients who achieved an SVR 12 - 24 weeks. These patients were mostly aged and with elevated AFP and advanced fibrosis. Monitoring and follow-up of those patients may help to assess the outcomes.

Detection of the Serum Cytokines Predicts COVID-19 Pathogenesis in Egyptian Patients.

Cytokine storms can be triggered by various infectious or noninfectious diseases and cause severe damages to multiple organs. Cytokine storm plays an important role in the pathogenesis of severe cases of coronavirus disease 2019 (COVID-19). The pathogenesis of COVID-19 involves a potent inflammatory response involving a complex group of mediators, including interleukin (IL)-6 and IL-10. In this study, the serum levels of IL-6 and IL-10 cytokines were evaluated in 79 COVID-19 infected patients from the National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt. And 20 healthy individuals served as a control group. The patients were divided into moderate, severe, and critically ill. In this study, IL-6 and IL-10 levels were significantly elevated in COVID-19 patients compared with healthy controls. IL-6 levels were significantly higher in patients compared with controls (p = 0.001), although it was not varied within different severity groups except for moderate-critical ill cases (p < 0.033). IL-10 only showed a significant difference between critically ill and control cases (p < 0.002). Receiver operating characteristic curve analyses showed that IL-6 levels >120 pg/mL can predict moderate and critically ill patients with a sensitivity of 90.48% and a specificity of 62.50%, Area Under the Curve <0.0001. In conclusion, the serum levels of IL-6 cytokine are important noninvasive biomarkers to differentiate between moderate and critically ill COVID-19 infected patients.

Influence of Blastocystis hominis on the small intestine and lactase enzyme activity.

Blastocystis hominis is a cosmopolitan protozoan that has been associated with several gastrointestinal disturbances involving lactose intolerance. However, the underlying pathogenic factors remain indistinct. 20 Swiss albino mice were utilized and assembled into four groups, each of five mice: group-I: received neither infection nor lactose (healthy control), group-II: received a single dose of 10,000 cysts of Blastocystis and lactose diets in a dose of 12.5 g/day/mouse for 7 consecutive days starting from day 14 p.i., group-III: non-infected mice with oral doses of lactose (12.5 g/day/mouse) for 7 consecutive days (positive control), group-IV: infected mice on lactose free diet (negative control). We investigated the histopathological changes using H&E stain.s Also, lactase enzyme activity was measured using spectrophotometry and the production of TNF-α and apoptotic events were explored via immunohistochemistry and compared in the small intestine of all groups. The active inflammatory changes in the infected animals were moderate in the form of loss of villous architecture, increased ILC (P-value > 0.001) besides scattered forms of the parasite as compared to non-infected mice. There was a reduction in lactase enzyme activity p.i. The TNF-α levels were induced p.i. as compared to non-infected mice (P-value > 0.001). The expression of Bax protein was upgraded, while Bcl-2 expression decreased significantly with a reverse in Bax/Bcl2 ratio in infected animals. Blastocystis infection appears to humble lactase enzyme activity via the induction of apoptosis in the epithelial cells of the small intestinal brush border in a TNF-α associative pathway.

Synthesis and characterization of amoxicillin-loaded polymeric nanocapsules as a drug delivery system targeting Helicobacter pylori.

BACKGROUND AND STUDY AIMS: Helicobacter pylori (H. pylori) is well known as the main cause of gastritis, gastroduodenal ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Approximately 50% of the world's population is infected with H. pylori. In Egypt, a high prevalence of H. pylori infections has been reported in the general population. This study aimed to prepare amoxicillin-loaded poly (ɛ-caprolactone) nanocapsules to increase its gastric stability and therapeutic activity of the molecule against H. pylori. MATERIALS AND METHODS: In this study, we used the water-oil-water double-emulsion technique to prepare spherical-shaped polymeric nanocapsules containing amoxicillin trihydrate as the core substance and biodegradable biocompatible poly (ɛ-caprolactone) as the shell material. RESULTS: The encapsulation efficiency obtained was 97.2% ± 0.8%. The hydrodynamic diameter of the prepared nanocapsules was 287 ± 8 nm with a positive zeta potential. In vitro release studies indicated that the polymeric nanocapsules showed decreased release percentages at pH 1.2, simulating the gastric fluid while relatively increased release at pH 7.0 where the H. pylori reside. The in vitro antibacterial assay showed better efficiency for amoxicillin nanocapsules than for the uncapsulated free amoxicillin, no efficiency was detected for the PCL nanocapsules indicated that the antibacterial due to amoxicillin alone. Cytotoxicity studies demonstrated less cytotoxicity for the polymeric nanocapsules in comparison with amoxicillin. CONCLUSIONS: In conclusion, we have demonstrated that biodegradable polymeric nanocapsules are useful drug delivery agents for increasing the gastric stability and therapeutic activity of amoxicillin trihydrate against H. pylori.

Expression of HCV genotype-4 core antigen in prokaryotic E. coli system for diagnosis of HCV infection in Egypt.

BACKGROUND: Egypt has a high prevalence of hepatitis C virus (HCV) infection with 92.5% of genotype-4. AIM: This study aimed to clone and express the core gene of HCV genotype-4 for using it to develop a highly sensitive, specific, and cost-effective diagnostic assay for detecting HCV infection. METHODS: Using synthetic HCV genotype-4 core gene, pET15b as E. coli expression vector, and 1 mM lactose as inducer, the HCV core protein (MW 17 kDa) was expressed in the form of inclusion bodies (IBs) that was purified and solubilized using 8 M guanidinium HCl. The recombinant core protein was in vitro refolded by a rapid dilution method for further purification using weak cation exchange liquid chromatography. The immunogenicity of the purified protein was tested by ELISA using 129 serum samples. RESULTS: The recombinant core protein was successfully expressed and purified. The results also showed that the in-house anti-HCV core assay is accurate, specific (~96.6%), and highly sensitive (~100%) in accordance with the commercial ELISA kit. CONCLUSION: The sensitivity, specificity, and reproducibility of the developed assay were high and promising to be used as a screening assay for detecting HCV infection.

Combinatory Effects of Cerium Dioxide Nanoparticles and Acetaminophen on the Liver-A Case Study of Low-Dose Interactions in Human HuH-7 Cells.

The interactions between pharmaceuticals and nanomaterials and its potentially resulting toxicological effects in living systems are only insufficiently investigated. In this study, two model compounds, acetaminophen, a pharmaceutical, and cerium dioxide, a manufactured nanomaterial, were investigated in combination and individually. Upon inhalation, cerium dioxide nanomaterials were shown to systemically translocate into other organs, such as the liver. Therefore we picked the human liver cell line HuH-7 cells as an in vitro system to investigate liver toxicity. Possible synergistic or antagonistic metabolic changes after co-exposure scenarios were investigated. Toxicological data of the water soluble tetrazolium (WST-1) assay for cell proliferation and genotoxicity assessment using the Comet assay were combined with an untargeted as well as a targeted lipidomics approach. We found an attenuated cytotoxicity and an altered metabolic profile in co-exposure experiments with cerium dioxide, indicating an interaction of both compounds at these endpoints. Single exposure against cerium dioxide showed a genotoxic effect in the Comet assay. Conversely, acetaminophen exhibited no genotoxic effect. Comet assay data do not indicate an enhancement of genotoxicity after co-exposure. The results obtained in this study highlight the advantage of investigating co-exposure scenarios, especially for bioactive substances.

Bioinformatics prediction of B and T cell epitopes within the spike and nucleocapsid proteins of SARS-CoV2.

BACKGROUND: The striking difference in severity of SARS CoV2 infection among global population is partly attributed to viral factors. With the spike (S) and nucleocapsid (N) are the most immunogenic subunits, genetic diversity and antigenicity of S and N are key players in virulence and in vaccine development. AIM: This paper aims at identifying immunogenic targets for better vaccine development and/or immunotherapy of COVID 19 pandemic. METHODS: 18 complete genomes of SARS CoV2 (n=14), SARS CoV (n=2) and MERS CoV (n=2) were examined. Bioinformatics of viral genetics and protein folding allowed functional tuning of NH2 Terminal Domain (NTD) of S protein and development of epitope maps for B and T cell responses. CONCLUSION: A deletion of amino acid residues Y144 and G107 were discovered in NTD of S protein derived from Indian and French isolates resulting in altered pocket structure exclusively located in NTD and reduced affinity of NTD binding to endogenous nAbs and disrupted NTD mediated cell entry. We therefore, proposed a set of B and T cell epitopes based on Immune Epitope Database, homologous epitopes for nAbs in convalescent plasma post SARS CoV infection and functional domains of S (NTD, Receptor Binding domain and the unique polybasic Furin cleavage site at S1/S2 junction). Nevertheless, laboratory data are required to develop vaccine and immunotherapeutics.

Recipient interleukin 6 gene polymorphism and expression predict HCV recurrence post liver transplantation.

BACKGROUND: Liver transplantation (LTX)is a lifesaving- effective protocol for patients suffering end stage liver disease (ESLD) and its complications post HCV infection. Recurrence of disease is a frequent clinical complication that is observed in patients undergoing LTX. Cytokines play a central role in the immunological events occurring after the surgery. METHODS: Using Allelic Discrimination PCR, the allelic variation G174C of IL-6 gene was investigated. The abundance of IL6- mRNA and plasma IL6 cytokine levels were evaluated by using qRT-PCR in peripheral blood mononuclear cells (PBMCs) and enzyme-linked immunosorbent assay (ELISA) respectively in 76 liver transplant recipients recruited from Al Sahel teaching hospital, Ministry of Health and Population Cairo Egypt within the period between June 2015 and October 2017. RESULTS: The frequencies of IL-6 GG genotype and the G allele were significantly detected more in LTX recipients who experienced HCV recurrence versus those who did not suffer recurrence when compared to healthy controls (P = 0.001) and (P = 0.006), respectively. On the contrary, levels of IL-6 related transcripts in PBMC's of recurrent patients were indifferent from non-recurrent patients and healthy controls (P ≥ 0.124). Interestingly, the circulating IL-6 protein in plasma was significantly elevated in recurrent as compared to the non-recurrent recipients (P = 0.002). CONCLUSION: HCV recurrence post liver transplantation occur more frequently in patients with -174 G/G IL-6 genotype and elevated plasma IL-6 levels.

Synthesis, physicochemical characterization, toxicity and efficacy of a PEG conjugate and a hybrid PEG conjugate nanoparticle formulation of the antibiotic moxifloxacin.

Antibiotic resistance is increasing at such an alarming rate that it is now one of the greatest global health challenges. Undesirable toxic side-effects of the drugs lead to high rates of non-completion of treatment regimens which in turn leads to the development of drug resistance. We report on the development of delivery systems that enable antibiotics to be toxic against bacterial cells while sparing human cells. The broad-spectrum fluoroquinolone antibiotic moxifloxacin (Mox) was successfully conjugated to poly(ethylene glycol) (PEG) which was further encapsulated into the hydrophobic poly(ε-caprolactone) (PCL) nanoparticles (NPs) with high efficiency, average particle size of 241.8 ± 4 nm and negative zeta potential. Toxicity against erythrocytes and MDBK cell lines and drug release in human plasma were evaluated. Hemocompatibility and reduced cytotoxicity of the PEG-Mox and PCL(PEG-Mox) NPs were demonstrated in comparison to free Mox. Antimicrobial activity was assessed against drug sensitive and resistant: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. The antibacterial activity of Mox was largely maintained after conjugation. Our data shows that the toxicity of Mox can be effectively attenuated while, in the case of PEG-Mox, retaining significant antibacterial activity. At the conditions employed in this study for antimicrobial activity the encapsulated conjugate (PCL(PEG-Mox) NPs) did not demonstrate, conclusively, significant antibacterial activity. These systems do, however, hold promise if further developed for improved treatment of bacterial infections.

The renin angiotensin system in liver and lung: impact and therapeutic potential in organ fibrosis.

Liver and lung fibrosis are two main organ diseases that are of particular importance in both Egypt and the US. Hepatitis C Virus "HCV" infection and idiopathic pulmonary fibrosis (IPF) are fibrotic diseases of the liver and lung respectively. The liver and lung are reported in literature to share many immune/inflammatory responses to damage through the lung-liver axis. Most importantly, HCV was shown to enhance the development of IPF and is considered one of the risk factors for IPF. The renin angiotensin system (RAS) plays a critical role in the fibrogenesis and inflammation damage of many organs including liver and lung. The relatively recently identified component of RAS, angiotensin converting enzyme-2 (ACE-2), has shown a promising therapeutic potential in models of liver and pulmonary fibrosis. This article reviews the role of RAS in organ fibrosis with focus on role of ACE-2 in fibrotic diseases of the liver and the lung.

The Role of MicroRNAs in Response to Interferon Treatment of Chronic Hepatitis C patients.

INTRODUCTION: Treatment of HCV using a combination of pegylated interferon (PEG-IFN) and ribavirin fails in about 40% of the patients with HCV genotype 4 infections, and it is physically and economically demanding. Thus, it is highly important to identify factors that can help to predict the likelihood that a patient will respond to this treatment. METHODS: In this study, five miRNAs, i.e., miRNA-122, miRNA-199, miRNA-192, miRNA-30, and miRNA-128, were selected according to previous studies that demonstrated their noticeable functions in viral replication, indicating that they potentially could be used by host cells to control viral infections. The five miRNAs were measured using real-time, reverse transcription-polymerase chain reactions. The data were analyzed using the t-test and chi-squared test. RESULTS: We found that the expression level of miRNA-122 was significantly increased in the responders' group (p < 0.01) over that in the non-responders' groups before and after treatment; both increased significantly (p < 0.01) compared with the normal control group. CONCLUSION: miR-122 might be a useful predictor for virological responses to treatment with PEG-interferon plus ribavirin therapy in patients with HCV.

Prevalence of mutations within major hydrophilic region of hepatitis B virus and their correlation with genotypes among chronically infected patients in Egypt.

BACKGROUND AND STUDY AIMS: Mutations within the major hydrophilic region (MHR) of the hepatitis B surface antigen (HBsAg) have been reported in relation to viral persistence by evasion from vaccine and immunotherapy, severity of liver disease and lack of detection by commercial kits. The aim of this study was to elucidate the circulation of hepatitis B virus (HBV) genotypes, subgenotypes and serotypes in Egypt, with recognition of the pattern and prevalence of MHR mutations possibly occurring during the course of the disease. PATIENTS AND METHODS: Eighty-eight samples from patients with chronic HBV infection were included in the study. The surface protein-encoding gene (S gene) in the HBV genome was subjected to amplification and partial sequencing. RESULTS: Based on phylogenetic analysis, only genotype D was found circulating among patients. The majority of isolates belonged to subgenotype D3 (86.3%), followed by D7 (8%), then D5 (3.4%) and lastly D1 (2.3%). Two subtypes were identified: ayw2 (97%) and ayw3 (2%). The 'w' sub-determinant was not defined in one isolate (1%). A significant proportion of patients (13/88, 14.8%) exhibited mutations in the MHR, 10 of whom harboured mutations in the 'a' determinant region and three outside. The first loop comprised four patients with three mutations (P127S, P127T and Y134F). The second loop contained six patients, all with one mutation, S143L, which was most frequently encountered in this study (6.8%). CONCLUSIONS: We conclude that genotype D, subgenotype D3 and HBsAg subtype ayw2 are the most common types circulating in Egypt, which account for 100%, 86.3% and 97% of the population, respectively, with a moderate degree of MHR mutations.

Circulating miRNAs as Predictor Markers for Activation of Hepatic Stellate Cells and Progression of HCV-Induced Liver Fibrosis.

INTRODUCTION: Liver fibrosis is the excessive accumulation of extracellular matrix that occurs by activation of hepatic stellate cells (HSCs), which has been identified as the major driver of liver fibrosis. Several studies confirmed that miRNAs have regulatory effects on the activation of HSCs by affecting the signaling pathways. The aim of this study was to develop non-invasive diagnostic markers by measuring different circulating miRNAs in serum as predictor markers for early diagnosis of liver fibrosis and its progression. METHODS: In this case-control study, we enrolled 66 subjects with chronic hepatitis C (CHC) with early stage of fibrosis and 65 subjects with CHC with late-stage fibrosis. Also, 40 subjects were included as normal controls. The six main miRNAs, i.e., miR-138, miR-140, miR-143, miR-325, miR-328, and miR-349, were measured using the reverse transcription-polymerase chain reaction. RESULTS: In the cases of CHC both with early and late stage of fibrosis, the circulating levels of the six main miRNAs were significantly higher than the levels in the control group. ROC analysis indicated that the sensitivity and specificity of miR-138 were 89.3% and 71.43%, respectively, in the early stage of fibrosis. In the late stage, the sensitivity and specificity of miR-138 were 89.3 and 93.02%, respectively, whereas, for miR-143, they were 75.0 and 88.4%, respectively. CONCLUSIONS: Circulating miR-138 could serve as a non-invasive biomarker for the detection of early fibrosis. Also, miR-138 and miR-143 could be specific biomarkers for indicating the late stage of liver fibrosis.

Detection of carcinogenic metals in kidney stones using ultraviolet laser-induced breakdown spectroscopy.

The UV single-pulsed (SP) laser-induced breakdown spectroscopy (LIBS) system was developed to detect the carcinogenic metals in human kidney stones extracted through the surgical operation. A neodymium yttrium aluminium garnet laser operating at 266 nm wavelength and 20 Hz repetition rate along with a spectrometer interfaced with an intensified CCD (ICCD) was applied for spectral analysis of kidney stones. The ICCD camera shutter was synchronized with the laser-trigger pulse and the effect of laser energy and delay time on LIBS signal intensity was investigated. The experimental parameters were optimized to obtain the LIBS plasma in local thermodynamic equilibrium. Laser energy was varied from 25 to 50 mJ in order to enhance the LIBS signal intensity and attain the best signal to noise ratio. The parametric dependence studies were important to improve the limit of detection of trace amounts of toxic elements present inside stones. The carcinogenic metals detected in kidney stones were chromium, cadmium, lead, zinc, phosphate, and vanadium. The results achieved from LIBS system were also compared with the inductively coupled plasma-mass spectrometry analysis and the concentration detected with both techniques was in very good agreement. The plasma parameters (electron temperature and density) for SP-LIBS system were also studied and their dependence on incident laser energy and delay time was investigated as well.

Occult Hepatitis C Virus Infection in Hemodialysis Patients; Single Center Study.

INTRODUCTION: A new form of hepatitis C virus infection, known as occult hepatitis C virus (HCV) infection, is characterized by the presence of HCV_RNA in the liver or peripheral blood mononuclear cells (PBMCs). However, no serological markers of infection occur and there is not as much damage to the liver damage as is produced by chronic hepatitis C. There is a high incidence of HCV infection among hemodialysis patients, there is significant concern about viral transmission. HCV infection is a major problem in hemodialysis (HD) units even though blood products are screened for anti-HCV antibodies and other precautions are taken. The aim of this study was to determine the prevalence of occult HCV infection in PBMC in chronic hemodialysis (CHD) patients in the dialysis unit at Theodor Bilharz Research Institute (TBRI) with HCV antibodies and HCV RNA negativity irrespective of their liver function tests. METHODS: Fifty-three patients who were repeatedly were anti-HCV negative and serum HCV-RNA negative and on regular hemodialysis for > six months were enrolled in the study, which was conducted in the dialysis unit of Nephrology Department at TBRI; there were 10 healthy matched controls. The patients were classified into two groups according to the result HCV RNA in their PBMCs. Serological markers of HCV infection, including anti-HCV antibody and serum HCV-RNA, were repeatedly negative for all patients included in the study. We collected serum and PBMC samples from the patients on the day they entered the study. The test of all serum samples for anti-HCV antibodies and HCV-RNA was repeated by RT-PCR to ensure that the patients did not have these HCV serologic markers, We also measured their ALT and GGT levels. RESULTS: Occult hepatitis C virus infection (OCI) was detected in 15.1% of our CHD patients without any evidence of chronic liver disease. CONCLUSION: Occult HCV infection was present among the hemodialysis patients irrespective of whether they had persistent abnormal values of liver enzymes for which no cause had been identified. Further study is required to determine the clinical significance of occult HCV infections in these patients.

Insulin resistance: a major factor associated with significant liver fibrosis in Egyptian patients with genotype 4 chronic hepatitis C.

BACKGROUND AND AIMS: The role of insulin resistance (IR) in chronic hepatitis C genotype 4 (CHC-4) patients is still under assessment. The aims of this study are to assess the prevalence and predictors of IR and its influence along with clinical, metabolic, virological, and histological factors on the severity of liver fibrosis in 100 Egyptian patients with CHC-4. PATIENTS AND METHODS: In 100 untreated patients with CHC-4, IR was assessed using the Homeostasis Model Assessment and defined greater than 3. By logistic regression (LR), independent factors associated with IR and significant fibrosis (SF=fibrosis, Metavir score≥F2) were assessed in nondiabetic and noncirrhotic patients. RESULTS: One hundred patients were included; 54% were men and 46% were women. The mean age of the patients was 40.46±9.41 years. Of the total patients, 55% were overweight and 28% were obese. Metabolic syndrome was observed in 26% of patients; five of them were known to be diabetic. All patients were genotype 4. Most of our patients had mild viremia (<2 00 000 IU/ml), whereas only 16% had higher viral load (>2 00 000 IU/ml). There was no correlation between IR and hepatitis C virus viremia (r=-0.069; P=0.492). Necroinflammation was moderate-severe (A2-A3) in 25% of patients. SF (F2-F4) was found in 46% of patients and 11% had cirrhosis (F4). Most of our patients, 54%, had moderate steatosis and 21% had severe steatosis. IR was present in 46% of patients; 39 (42.9%) were nondiabetic, which is correlated significantly with BMI (r=0.395; P<0.01). IR was found to increase significantly with the fibrosis stage (P=0.001), insignificant fibrosis, 18.5%, SF (F2-F4), 71.4%, and cirrhosis (F4), 100%. By LR, IR was independently and significantly associated with age more than 40 years, obesity (BMI>30 kg/m), SF, and severe steatosis (>30%). IR was also significantly associated with metabolic syndrome. SF was present in 46 patients (46%). It was associated with IR, moderate-severe necroinflammation, and severe steatosis. By LR, in noncirrhotic patients, SF was associated with age more than 40 years, obesity (BMI>30 kg/m), moderate/severe liver inflammation, and severe steatosis. CONCLUSION: In CHC-4 patients, IR is highly prevalent and independently associated with age, obesity, SF, and severe steatosis. Management of IR might significantly improve the prognosis of CHC-4 patients.