Relative carcinogenicity of tacrolimus vs mycophenolate after solid organ transplantation and its implications for liver transplant care

BACKGROUND

De novo malignancy is a leading cause of late morbidity and mortality in liver transplant recipients. Cumulative immunosuppression has been shown to contribute to post-transplant malignancy (PTM) risk. There is emerging evidence on the differential carcinogenic risk profile of individual immunosuppressive drugs, independent of the net effect of immunosuppression. Calcineurin inhibitors such as tacrolimus may promote tumourigenesis, whereas mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil, may limit tumour progression. Liver transplantation (LT) is relatively unique among solid organ transplantation in that immunosuppression monotherapy with either tacrolimus or MPA is often achievable, which makes careful consideration of the risk-benefit profile of these immunosuppression agents particularly relevant for this cohort. However, there is limited clinical data on this subject in both LT and other solid organ transplant recipients.

AIM

To investigate the relative carcinogenicity of tacrolimus and MPA in solid organ transplantation.

METHODS

A literature search was conducted using MEDLINE and Embase databases using the key terms "solid organ transplantation", "tacrolimus", "mycophenolic acid", and "carcinogenicity", in order to identify relevant articles published in English between 1st January 2002 to 11th August 2022. Related terms, synonyms and explosion of MeSH terms, Boolean operators and truncations were also utilised in the search. Reference lists of retrieved articles were also reviewed to identify any additional articles. Excluding duplicates, abstracts from 1230 records were screened by a single reviewer, whereby 31 records were reviewed in detail. Full-text articles were assessed for eligibility based on pre-specified inclusion and exclusion criteria.

RESULTS

A total of 6 studies were included in this review. All studies were large population registries or cohort studies, which varied in transplant era, type of organ transplanted and immunosuppression protocol used. Overall, there was no clear difference demonstrated between tacrolimus and MPA in de novo PTM risk following solid organ transplantation. Furthermore, no study provided a direct comparison of carcinogenic risk between tacrolimus and MPA monotherapy in solid organ transplantation recipients.

CONCLUSION

The contrasting carcinogenic risk profiles of tacrolimus and MPA demonstrated in previous experimental studies, and its application in solid organ transplantation, is yet to be confirmed in clinical studies. Thus, the optimal choice of immunosuppression drug to use as maintenance monotherapy in LT recipients is not supported by a strong evidence base and remains unclear.

The Amyloid Precursor Protein Modulates the Position and Length of the Axon Initial Segment

The amyloid precursor protein (APP) is linked to the genetics and pathogenesis of Alzheimer's disease (AD). It is the parent protein of the β-amyloid (Aβ) peptide, the main constituent of the amyloid plaques found in an AD brain. The pathways from APP to Aβ are intensively studied, yet the normal functions of APP itself have generated less interest. We report here that glutamate stimulation of neuronal activity leads to a rapid increase in App gene expression. In mouse and human neurons, elevated APP protein changes the structure of the axon initial segment (AIS) where action potentials are initiated. The AIS is shortened in length and shifts away from the cell body. The GCaMP8f Ca2+ reporter confirms the predicted decrease in neuronal activity. NMDA antagonists or knockdown of App block the glutamate effects. The actions of APP on the AIS are cell-autonomous; exogenous Aβ, either fibrillar or oligomeric, has no effect. In culture, APPSwe (a familial AD mutation) induces larger AIS changes than wild type APP. Ankyrin G and βIV-spectrin, scaffolding proteins of the AIS, both physically associate with APP, more so in AD brains. Finally, in humans with sporadic AD or in the R1.40 AD mouse model, both females and males, neurons have elevated levels of APP protein that invade the AIS. In vivo as in vitro, this increased APP is associated with a significant shortening of the AIS. The findings outline a new role for the APP and encourage a reconsideration of its relationship to AD.SIGNIFICANCE STATEMENT While the amyloid precursor protein (APP) has long been associated with Alzheimer's disease (AD), the normal functions of the full-length Type I membrane protein have been largely unexplored. We report here that the levels of APP protein increase with neuronal activity. In vivo and in vitro, modest amounts of excess APP alter the properties of the axon initial segment. The β-amyloid peptide derived from APP is without effect. Consistent with the observed changes in the axon initial segment which would be expected to decrease action potential firing, we show that APP expression depresses neuronal activity. In mouse AD models and human sporadic AD, APP physically associates with the scaffolding proteins of the axon initial segment, suggesting a relationship with AD dementia.

Alcohol reverses the effects of KCNJ6 (GIRK2) noncoding variants on excitability of human glutamatergic neurons

Synonymous and noncoding single nucleotide polymorphisms (SNPs) in the KCNJ6 gene, encoding G protein-gated inwardly rectifying potassium channel subunit 2 (GIRK2), have been linked with increased electroencephalographic frontal theta event-related oscillations (ERO) in subjects diagnosed with alcohol use disorder (AUD). To identify molecular and cellular mechanisms while retaining the appropriate genetic background, we generated induced excitatory glutamatergic neurons (iN) from iPSCs derived from four AUD-diagnosed subjects with KCNJ6 variants ("Affected: AF") and four control subjects without variants ("Unaffected: UN"). Neurons were analyzed for changes in gene expression, morphology, excitability and physiological properties. Single-cell RNA sequencing suggests that KCNJ6 AF variant neurons have altered patterns of synaptic transmission and cell projection morphogenesis. Results confirm that AF neurons express lower levels of GIRK2, have greater neurite area, and elevated excitability. Interestingly, exposure to intoxicating concentrations of ethanol induces GIRK2 expression and reverses functional effects in AF neurons. Ectopic overexpression of GIRK2 alone mimics the effect of ethanol to normalize induced excitability. We conclude that KCNJ6 variants decrease GIRK2 expression and increase excitability and that this effect can be minimized or reduced with ethanol.

The baculovirus promoter OpIE2 sequence has inhibitory effect on the activity of the cytomegalovirus (CMV) promoter in HeLa and HEK-293 T cells

Understanding how promoters work in non-host cells is complex. Nonetheless, understanding this process is crucial while performing gene expression modulation studies. This study began with the process of constructing a shuttle vector with CMV and OpIE2 promoters in a tandem arrangement to achieve gene expression in both mammalian and insect cells, respectively. In this system, inhibitory regions in the 5' end of the OpIE2 insect viral promoter were found to be blocking the activity of the CMV promoter in mammalian cells. Initially, the OpIE2 promoter was cloned downstream of the CMV promoter and upstream of the EGFP reporter gene. After introducing the constructed shuttle vector to insect and mammalian cells, a significant drop in the CMV promoter activity in mammalian cells was observed. To enhance the CMV promoter activity, several modifications were made to the shuttle vector including site-directed mutagenesis to remove all ATG codons from the downstream promoter (OpIE2), separating the two promoters to eliminate the effect of transcription interference between them, and finally, identifying some inhibitory regions in the OpIE2 promoter sequence. When these inhibitory regions were removed, high expression levels in insect and mammalian cells were maintained. In conclusion, a shuttle vector was constructed that works efficiently in both mammalian and insect cell lines in the absence of baculovirus infection or gene expression. Moreover, the shuttle vector can be used as a platform to further study the reason for this inhibition, which may give new insights about transcription and promoters' mode of action in both insect and mammalian hosts.

Association of genetic polymorphisms of chemokines and their receptors with clearance or persistence of hepatitis C virus infection

BACKGROUND

Polymorphisms of certain genes may have an effect on either persistence of infection or spontaneous clearance of hepatitis C virus (HCV). We hypothesized that one or more variants of chemokines (CCL2 and CCL5) and chemokine receptors (CC chemokine receptor type 2 [CCR2]) genes are associated with the susceptibility to HCV infection.

METHODS

We recruited 1460 patients with chronic HCV (CHC), 108 subjects with spontaneous virus clearance (SVC) and 1446 individuals as a healthy control group. All were genotyped for single nucleotide polymorphisms: rs13900 C/T of CCL2, rs3817655 T/A of CCL5 and rs743660 G/A and rs1799864 G/A of CCR2 using allelic discrimination real-time PCR technique.

RESULTS

The carriage of the A allele of CCR2 rs743660 was significantly higher in CHC compared to SVC (odds ratio [OR] 4.03) and to controls (1.42) and in controls compared to SVC (2.85) (all P < 0.01). Similarly, the A allele of CCR2 rs1799864 was significantly higher in the CHC group when compared with both SVC (1.97) and controls (2.13) (both P < 0.01), but the OR between controls and SVC was not significant (1.08, P = 0.723). Carriage of C allele of CCL2 rs13900 and the T allele of CCL5 rs3817655 were significantly higher in SVC group when compared with both CHC (OR = 0.19 and OR = 0.24, respectively) and control groups (OR = 0.65 and OR = 0.45, respectively [all P < 0.01]).

CONCLUSIONS

Susceptibility to HCV infection is associated with A alleles of both (rs743660 and rs1799864 G/A) of CCR2 while spontaneous clearance of HCV is associated with the C allele of rs13900 of CCL2 and T allele of rs3817655 of CCL5.

Urinary bisphenol A concentrations in relation to asthma in a sample of Egyptian children

BACKGROUND

Bronchial asthma is one of the top disabling diseases in pediatrics. Limited research has been studied the association of the widely used plastic monomer bisphenol A (BPA) with childhood asthma.

OBJECTIVE

To compare the levels of urinary BPA in asthmatic and control children and to investigate the implication of BPA among other risk factors for the development of asthma.

SUBJECTS AND METHODS

This case-control study included 97 children (45 asthmatic and 52 healthy controls) aged 3-8 years. Asthmatic children were diagnosed according to Global initiative for asthma (GINA) guidelines. Sociodemographic factors were assessed and urinary levels of BPA were determined in spot urine samples using high-performance liquid chromatography. The contribution of BPA among predictors for developing asthma was studied in asthmatic children.

RESULTS

Median total urinary BPA levels were significantly higher in asthmatic children than in control group (1.56 ng/mL in asthmatic children compared to 0.790 ng/mL in control group, p = 0.001). Children who had total urinary BPA levels >1.3 ng/mL were more likely to be asthmatic (odds ratio: 2.84, 95% confidence interval 1.22-6.59, p = 0.015). Multiple logistic regression analysis for predictors of asthma showed the importance of higher levels of BPA (>1.3 ng/mL) as a more significant predictor than passive smoking ( p = 0.006 for BPA categories vs. p = 0.049 for passive smoking).

CONCLUSION

Association of higher levels of urinary BPA with the diagnosis of asthma in children may indicate the potential risk of BPA exposure in the precipitation of bronchial asthma. Further clinical and biochemical research are needed to clarify the proper mechanism explaining this association.

Cutaneous epithelioid angiomatous nodule: different views or interpretations in the analysis of ten new cases

Classification schemes proposed for vascular lesions are the subjects of significant controversy. Cutaneous epithelioid angiomatous nodule (CEAN) was described in 2004, but there is no agreement as to whether this is a distinct entity or a type of either epithelioid hemangioma or angiolymphoid hyperplasia with eosinophilia. We present a typical case of CEAN and discuss nine other cases from our institution. We then provide two opposing viewpoints concerning its classification.

Design and synthesis of azolopyrimidoquinolines, pyrimidoquinazolines as anti-oxidant, anti-inflammatory and analgesic activities

The 5,10-dihydro-2-thioxo-pyrimido[4,5-b]quinolines (2a-c) and its oxidized form 3 were prepared and used as key intermediates for the synthesis of thiazolo[3',2':1,2]pyrimido[4,5-b]-quinolines (5a-c), isoxazolo[5'',4'':4',5']thiazolo[3',2':1,2]pyrimido[4,5-b]quinolines (6a-c), 4-chloro-2-methylthio-pyrimido[4,5-b]quinoline, its amino derivatives (19-21) and 10,11,12,13-tetrahydro-5H-quino[2',3':4,5]pyrimido[6,1-b]quinazoline (22). The newly synthesized compounds were characterized by IR, NMR (1H, 13C) and mass spectral studies. Representative of the synthesized compounds was tested and evaluated for anti-oxidant, anti-inflammatory and analgesic activities. Compounds 2a-c showed the highest inhibitory anti-oxidant activity either using erythrocyte hemolysis or ABTS methods. Compounds 2a, 10b, 16, and 17a manifested the best protective effect against DNA damage induced by bleomycin. Compounds 2c, 5a, 20a, 2a, and 2b exhibited a potent anti-inflammatory activity using carrageenan-induced paw edema test in rats.

Immunopathogenesis of attenuated strain of chicken infectious anemia virus in one-day-old specific-pathogen-free chicks

In the present study, the immunopathogenicity of chicken anemia virus (CAV) vaccinal strain was studied in one-day-old specific-pathogen-free (SPF) chicks. Hematocrit values, histopathological changes in haemopioetic and lymphoid organs, ELISA for CAV antibodies and PCR for CAV genome were used as testing assays for the study. Vaccinated chicks showed signs of anemia, lower hematocrit values and histopathological lesions in liver in the form of hepatocytes swelling to Centro lobular necrosis and apoptosis. Histopathology change in spleen (depletion of lymphocytes and apoptosis) and thymus (depletion of thymocytes and apoptosis) together with variable degrees of seroconversion rate were observed along the 10 weeks of the experiment indicating 2 waves of immune response in vaccinated chicks compared to the control non-vaccinated group. Detection of CAV-DNA in the liver of vaccinated chicks indicated the presence of the virus, when the antibody levels were decreased in some chicks. There was a consistent correlation between the 4 parameters used. It is concluded that the attenuated CAV vaccine strain induces anemia and lesions in the lymphoid organs. The histopathology and PCR are useful tools for evaluation and quality assurance of CAV vaccines.

Effect of octreotide on the pathology of hepatic schistosomiasis

In clinical practice, octreotide (CAS 83150-76-9) has its greatest impact in the management of bleeding varices. The present work is the first one which was undertaken to investigate the possible use of octreotide as an antifibrotic agent and to study its effect on hepatic vasculature in Schistosoma mansoni infection. The material of this investigation consisted of two groups of albino mice (A, B), subdivided each into normal control, infected control, subgroups treated with octreotide, praziquantel (CAS 55268-74-1), and a combination of octreotide and praziquantel. Groups A and B were sacrificed at the 8th week and the 18th week post infection, respectively. By analysis of the obtained results, octreotide induced a reduction of the portal pressure, the weight of the spleen and the liver, the liver egg load (number of eggs) granuloma size and cellularity, and of the degree of hepatic fibrosis quantified by serum N-terminal peptide of type III procollagen in serum, serum laminin and tissue collagen using a Picrosirius red dye assay. Moreover, the biochemical state of hepatocytes has been improved. The subgroups treated with octreotide in association with praziquantel revealed better results than the subgroups treated with praziquantel alone. These obtained data were analysed in terms of histological extent of liver fibrosis in sections stained with Masson trichrome and sirius red, hepatocytic and sinusoidal changes at an ultrastructural level and by immunohistochemical demarcation of endothelial cells of blood vessels through the determination of factor VIII-related antigen. The promising results detected in this study may encourage to further investigate the positive findings of this drug with the intention of its possible application on a clinical level.

Octreotide decreases connective tissue formation and improves vascular changes associated with hepatic schistosomiasis

In clinical practice, Octreotide has its greatest impact in the management of bleeding varices. The present work is the first one which was undertaken to investigate the possible use of Octreotide as an antifibrotic agent and to study its effect on hepatic vasculature in Schistosoma mansoni infection. The material of this investigation consisted of two groups of albino mice (A&B) subdivided each, into normal control, infected control, Octreotide treated, Praziquantel treated and Octreotide with Praziquantel treated subgroups. Groups A & B were sacrificed at the 8th week and the 18th week post infection respectively. By analysis of the obtained results, Octreotide has induced reduction of the portal pressure, the weight of the spleen and the liver, the number of liver egg load, granuloma size and cellularity, and of the degree of hepatic fibrosis quantified by serum PIIINP, serum laminin and tissue collagen using sirius red dye assay. Moreover, the biochemical state of hepatocytes has been improved. The subgroups treated with Octreotide in association with Praziquantel revealed better results than the subgroups treated with Praziquantel alone. Data were analysed in terms of histological extent of liver fibrosis in sections stained with Masson trichrome and sirius red, hepatocytic and sinusoidal changes at an ultrastuctural level and by immunohistochemical demarcation of endothelial cells of blood vessels through the determination of factor VIII related antigen. The promising results detected in this study may encourage to further investigate the positive findings of this drug with the intention of its possible application on a clinical level.

Aminosidine sulphate in experimental cryptosporidiosis

The present study aimed at investigating the efficiency of a recent antibiotic Aminosidine sulphate (Gabbroral) in experimental cryptosporidiosis. The course of infection was studied when the drug was given early before the infection, and late during the infection both parasitologically and histopathologically. When the drug was given early, the results were satisfactory, with a significant reduction of size, number and pathological changes of the parasites in the stool and in ileal sections of infected mice. However, the drug had no effect when given late during the infection.

Selected nutritional, physical and sensory characteristics of pan and flat breads prepared from composite flours containing fababean

Composite flour blends containing wheat (W), fababean (F), cottonseed and sesame flours were formulated to provide the FAO/WHO/UNU protein requirements for the 2-5 year old child, and evaluated in pan and flat bread applications. Water absorption of composite flour doughs was up to 35% greater than the control but gluten strength and slurry viscosities were markedly reduced. Loaf volume and specific volume of pan breads prepared from composite flours were 25-60% less than that of the control bread but flat breads tolerated the protein supplements extremely well. The W/F flat bread, containing 27% of fababean flour, received acceptable taste, texture and colour scores and was only slightly inferior to the control in puffing and layer separation. Additions of cottonseed or sesame flours to the W/F blend failed to improve sensory properties of the flat breads.

A study on experimental cryptosporidiosis

Cryptosporidium oocysts were isolated from stools of infected patients diagnosed as cryptosporidiosis. Suckling Swiss albino mice were infected orally by these oocysts in a dose of 10(6) oocysts/mouse. Mice were divided into 9 groups according to the duration of infection 2, 3, 4, 5, 6, 7, 10, 10, 15, 21 days postinfection, corresponding non infected control groups were included. Stools of infected mice were examined twice daily to determine; infection rate, prepatent period and intensity of infection. Mice were sacrificed according to the schedule and the whole intestine was isolated and processed for histopathological examination by H & E and modified Ziehl Nielsen stain, and histochemical examination for acid and alkaline phosphatase activity. The results revealed that the infection rate was 90% and prepatent period 3-5 days and the course of infection was 21 days. The maximum pathological changes were in the ileum. These changes were reversible.

The efficacy of IHAT, IFAT and Dot-ELISA in sero-diagnosis of toxoplasmosis in complicated pregnancies

Studying of 72 pregnant women having congenital anomalies, stillbirth and repeated abortion of first and second trimesters showed Toxoplasma antibodies with high titre by IFAT and Dot-ELISA. Analysis of the results showed a positive correlation between IFAT and Dot-ELISA but not with IHAT. However, Dot-ELISA is simple, sensitive and specific.

Evaluation of Fasciola somatic antigenic fractions in the diagnosis of human fascioliasis

Fasciola somatic antigen was fractionated by column chromatography. Four peaks were obtained. They were evaluated separately using IgG and IgM ELISA in the diagnosis of fascioliasis. Patients were diagnosed through a survey in Abis 13/4 Village depending on stool examination, clinical, haematological findings and on the results of IHAT. Sera were obtained from cases of confirmed fascioliasis, acute fascioliasis, schistosomiasis and from parasite free healthy individuals. After establishing the optimal conditions for the test, ELISA was performed using all fraction and all sera. The results were then computerized and specificity, sensitivity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and probability of disease when test is positive (PDP) were determined at different cut off levels. These parameters were calculated using both sera of normal cases and of S. mansoni infected cases as controls. It was concluded that fraction I in IgG ELISA was the best for diagnosis of chronic cases. Fraction I by IgM was the best for acute infection. Results of the latter antigen/system combination were not decreased when S. mansoni sera were used as control.

A preliminary study on vaginal trichomonal antigens using CIEP and modified ELISA

The enzyme linked immunosorbent assay (ELISA) and counter-immunoelectrophoresis (CIEP) were used to detect T. vaginalis antigens in vaginal discharge of 47 infected women and 35 controls. Rabbit antisera raised against T. vaginalis were used as antitrichomonal antibodies. The sensitivity of ELISA was 95.7% and specificity was 91.4 in contrast to 68.1 and 77.1% for CIEP. So ELISA could be applied for epidemiological study and immunodiagnosis of vaginal trichomoniasis.

Immunization against Schistosoma mansoni by using Trichinella spiralis and Trichinella pseudospiralis antigens

The antigenic fraction of a cell free homogenate of each of Trichinella spiralis and T. pseudospiralis were prepared to be used for induction of immunity against S. mansoni in albino mice. The results of the study showed that immunization with either of the two antigens induced reduction in worm load ranging from 80.48% to 87.86% in the different groups of the study. Reduction in tissue egg count was also reported: Liver egg count was reduced from 69.47% to 100%. Intestinal egg count reduction ranged from 73.83% to 99.78%. There was also reduction in egg excretion as evidenced by diminution in stool egg count. Liver granulomas were less in number and size and showed accelerated reaction together with inhibition of fluorescence. These findings were more manifest in animals given T. spiralis than T. pseudospiralis antigen.

Formulation, acceptability, chemical composition and in vitro digestibility of novel snack food and meat ball analogue

Potato purée and wheat flour were blended at a ratio of 7:1 w/w with 2 parts per weight of soybean protein concentrate (SPC) and/or faba bean-protein micellar mass (PMM). Two snack foods were formulated and deep fried. Spices, onion, parsley and chicken stock were added to the aforementioned two recipes to formulate meat ball analogues. Data revealed good acceptability of all products. Moreover, they can be considered as a good source for some essential amino acids; protein (approximately 26%); lipids (approximately 20%); carbohydrates (approximately 48%) and minerals. The in vitro digestibility ranged between 61.0% and 66.9%.

Formulation and characteristics of new recipes of Egyptian patti beans (Falafel)

New recipes of Falafel were formulated and evaluated regarding acceptability, proximate chemical composition and nutritive value. Soybean meal and/or cotyledons were used to substitute for faba bean at different levels (i.e. zero %, 20%, 40%, 60%, 80% and 100%. Data indicated that blends of faba bean (20%) and soybean meal and/or cotyledons (80%) were the most acceptable recipes compared to the control (100% faba bean) as well as the other substitution levels. Blending soybean with faba bean led to appreciable improvement in some essential amino acids. The in vitro digestibility for soybean blends were comparable to the control.