Status of Serum Calcium, Phosphate and Intact Parathyroid Hormone in Predialysis Chronic Kidney Disease Patients of Stage-3 to Stage-5 Compared To KDOQI Guideline

The chronic kidney disease (CKD) is associated with a variety of bone disorders and disorders of calcium and phosphorus metabolism. Bone disease associated with chronic kidney disease having higher rate of CKD progression and increased risk of death. To see the status of serum calcium, phosphate and intact parathyroid hormone in pre-dialysis CKD (stage- 3 to 5) patients. This was a across sectional study done in outpatient department of Nephrology of National Institute of Kidney Diseases and Urology, Dhaka, between 1st June 2012 to 31st May 2013. The patients of CKD stage 3, 4 and 5 yet not on dialysis attending out patients department of Nephrology, NIKDU by using MDRD-4 equation according to K/DOQI guidelines and reviewing previous medical records and investigation reports were enrolled in this study. There after serum calcium (corrected for serum albumin), phosphate and iPTH levels were measured and compared with the recommended target ranges in K/DOQI guideline. The number of patients with serum levels according to K/DOQI guidelines for different stages CKD(3,4,5) were as follows: serum calcium: 56.6, 58.5 and 76.7; serum phosphate: 55.2, 58.5 and 56.7; iPTH 37.9, 12.2 and 36.7 and Ca x P product 100.0, 97.6 and 86.7, respectively. The percentages of patients (who received drug) with serum calcium levels within according to K/DOQI guidelines for stages 3, 4 and 5 were as follows: serum calcium: 63.2%, 64.7% and 83.3%; respectively, serum phosphate: 63.2%, 61.8% and 66.7%; respectively, iPTH 42.1%, 14.7% and 4.7% and Ca x P product 100.0%, 100.0% and 87.5%, respectively. On the other hand patients who didn't receive drug the percentages of patients with serum calcium levels according to K/DOQI guidelines for CKD stages 3, 4 and 5 were as follows: serum calcium: 50.0%, 28.6% and 50.0%; respectively, serum phosphate: 40.0%, 42.9% and 16.7%; respectively, iPTH 30.0%, 14.7% and 16.7% and Ca x P product 100.0%, 85.7% and 83.3%, respectively. The patients achieving the four recommendations of K/DOQI guidelines was 4(13.8%) in stage-3, 3(7.3%) in stage-4 and 5(16.7%) in stage-5. More than half of the pre-dialysis patients of CKD were within target range of serum calcium and phosphate recommended in K/DOQI guideline and this proportion was more in those who were taking both phosphate binder and Vit-D. Ca x P was within target range in almost all patients so it may not be an important parameter for therapeutic decision making. However majority of the patients were out of target range of iPTH even though having normal serum calcium and phosphate level. So emphasis should be given in monitoring of iPTH level in early stages of CKD.

Signaling Inhibitors Accelerate the Conversion of mouse iPS Cells into Cancer Stem Cells in the Tumor Microenvironment

Cancer stem cells (CSCs) are a class of cancer cells characterized by self-renewal, differentiation and tumorigenic potential. We previously established a model of CSCs by culturing mouse induced pluripotent stem cells (miPSCs) for four weeks in the presence of a conditioned medium (CM) of cancer cell lines, which functioned as the tumor microenvironment. Based on this methodology of developing CSCs from miPSCs, we assessed the risk of 110 non-mutagenic chemical compounds, most of which are known as inhibitors of cytoplasmic signaling pathways, as potential carcinogens. We treated miPSCs with each compound for one week in the presence of a CM of Lewis lung carcinoma (LLC) cells. However, one-week period was too short for the CM to convert miPSCs into CSCs. Consequently, PDO325901 (MEK inhibitor), CHIR99021 (GSK-3β inhibitor) and Dasatinib (Abl, Src and c-Kit inhibitor) were found to confer miPSCs with the CSC phenotype in one week. The tumor cells that survived exhibited stemness markers, spheroid formation and tumorigenesis in Balb/c nude mice. Hence, we concluded that the three signal inhibitors accelerated the conversion of miPSCs into CSCs. Similarly to our previous study, we found that the PI3K-Akt signaling pathway was upregulated in the CSCs. Herein, we focused on the expression of relative genes after the treatment with these three inhibitors. Our results demonstrated an increased expression of pik3ca, pik3cb, pik3r5 and pik3r1 genes indicating class IA PI3K as the responsible signaling pathway. Hence, AKT phosphorylation was found to be up-regulated in the obtained CSCs. Inhibition of Erk1/2, tyrosine kinase, and/or GSK-3β was implied to be involved in the enhancement of the PI3K-AKT signaling pathway in the undifferentiated cells, resulting in the sustained stemness, and subsequent conversion of miPSCs into CSCs in the tumor microenvironment.

Enhanced secretion of cyclodextrin glucanotransferase (CGTase) by Lactococcus lactis using heterologous signal peptides and optimization of cultivation conditions

In previous studies of Lactococcus lactis, the levels of proteins secreted using heterologous signal peptides were observed to be lower than those obtained using the signal peptide from Usp45, the major secreted lactococcal protein. In this study, G1 (the native signal peptide of CGTase) and the signal peptide M5 (mutant of the G1 signal peptide) were introduced into L. lactis to investigate the effect of signal peptides on lactococcal protein secretion to improve secretion efficiency. The effectiveness of these signal peptides were compared to the Usp45 signal peptide. The highest secretion levels were obtained using the G1 signal peptide. Sequence analysis of signal peptide amino acids revealed that a basic N-terminal signal peptide is not absolutely required for efficient protein export in L. lactis. Moreover, the introduction of a helix-breaking residue in the H-region of the M5 signal peptide caused a reduction in the signal peptide hydrophobicity and decreased protein secretion. In addition, the optimization of cultivation conditions for recombinant G1-CGTase production via response surface methodology (RSM) showed that CGTase activity increased approximately 2.92-fold from 5.01 to 16.89 U/ml compared to the unoptimized conditions.

Use of DNA-generated gold nanoparticles to radiosensitize and eradicate radioresistant glioma stem cells

The surface reactivity of gold nanoparticles (AuNPs) is receiving attention as a radiosensitizer of cancer cells for radiation therapy and/or as a drug carrier to target cells. This study demonstrates the potential of DNA-AuNPs (prepared by mixing calf thymus DNA with HAuCl₄ solution) as a radiosensitizer of human glioma cells that have cancer stem cell (CSC)-like properties, to reduce their survival. CSC-like U251MG-P1 cells and their parental glioblastoma U251MG cells are treated with a prepared DNA-AuNP colloid. The radiosensitivity of the resultant AuNP-associated cells are significantly enhanced. To reveal the mechanism by which survival is reduced, the generation of reactive oxygen species (ROS), apoptosis induction, or DNA damage in the cells is assayed using the fluorescent dye DCFDA, annexin V-FITC/PI, and foci formation of γ-H2AX, respectively. X-ray irradiation with administration of AuNPs overcomes the radioresistance of U251MG-P1 cells. It does not induce ROS generation or apoptosis in the cells but enhances the number of abnormal nuclei with abundant γ-H2AX foci, which is judged as cell death by mitotic catastrophe. The AuNP association with the cells effectively induces mitotic catastrophe in x-ray-irradiated CSC-like cells, implicating that DNA-AuNPs might be a promising tool to develop an efficient radiosensitizer against CSC.

Abstract 3055: A model of CSC converted from iPSC in the conditioned medium of HCC paving the way to establish HCC CSC

Hepatocellular carcinoma (HCC) represents the major histological subtype, accounting for 70%–85% of cases of primary liver cancer. Liver CSCs sustain their self-renewal remains largely unknown. The self-renewal and pluripotency of liver CSC are maintained by several signaling cascades. However, the mechanism of regulating these signaling is unknown.

In this study, we tried to convert mouse iPSCs into CSCs with the conditioned medium (CM) from human HCC cell line Huh7 cells without any genetic manipulation aiming at establishing liver CSCs.

First of all, CM was collected from confluent culture of Huh7 cells. Then, mouse iPSCs cells without MEF feeder cells were cultured in the presence of 50% CM for 4 weeks. The medium was changed every day with fresh medium containing 50% of CM. Mouse iPSCs cultured in the complete medium with LIF were used as a control.The survived cells (5x105 cells) were suspended in HBSS and injected into the liver of BALB/c nude mice. After 25 days malignant tumor was formed in the liver while benign teratoma was formed by the injection of iPSCs. Tumors were then excised and partly fixed in 10% neutral formalin buffer solution for HE staining and immunohistochemical analysis. The rest of tumors were subjected to rt-qPCR anaylsis and primary culture. Immunohistochemical analysis with GFP antibody showed that malignant tumor sustained GFP expression while teratoma from miPSCs did not. Immunocytochemistry of the primary cells from malignant tumor showed high expression of both glypican-3 (GPC3) and cytokeratin19 (CK19) when compared to that in miPSCs. Expression of stem cell markers (Nanog, Oct3/4, Sox2, Klf4) and CSC markers (CD44, EpCAM) were also confirmed by rt-qPCR in both the CSCs converted from iPSCs (miPS-Huh7cm cells) and the primary culture cells. These results indicate that the primary cells from the malignant tumor are rich in CSCs with high expression of GPC3 and CK19, which paves the way to establish a model of HCC CSC. This model should be very important and useful to assess the significant molecular mechanisms necessary to maintain HCC CSC, which will help develop effective therapy of liver cancer.

Citation Format: Said M Afify, Anna Sanchez Calle, Kazuki Kumon, Hend M Nawara, Apriliana C Khairani, Hafizah Mahmud, Aung Ko Ko Oo, Du Juan, Maram H Zahara, Akimasa Seno, Tomonari Kasai, Yoshiaki Iwasaki, Masaharu Seno. A model of CSC converted from iPSC in the conditioned medium of HCC paving the way to establish HCC CSC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3055.

Up-Regulation of PI 3-Kinases and the Activation of PI3K-Akt Signaling Pathway in Cancer Stem-Like Cells Through DNA Hypomethylation Mediated by the Cancer Microenvironment

Previously, we have succeeded in converting induced pluripotent stem cells (iPSCs) into cancer stem cells (CSCs) by treating the iPSCs with conditioned medium of Lewis lung carcinoma (LLC) cells. The converted CSCs, named miPS-LLCcm cells, exhibited the self-renewal, differentiation potential, and potential to form malignant tumors with metastasis. In this study, we further characterized miPS-LLCcm cells both in vivo and in vitro. The tumors formed by subcutaneous injection showed the structures with pathophysiological features consisting of undifferentiated and malignant phenotypes generally found in adenocarcinoma. Metastasis in the lung was also observed as nodule structures. Excising from the tumors, primary cultured cells from the tumor and the nodule showed self-renewal, differentiation potential as well as tumor forming ability, which are the essential characters of CSCs. We then characterized the epigenetic regulation occurring in the CSCs. By comparing the DNA methylation level of CG rich regions, the differentially methylated regions (DMRs) were evaluated in all stages of CSCs when compared with the parental iPSCs. In DMRs, hypomethylation was found superior to hypermethylation in the miPS-LLCcm cells and its derivatives. The hypo- and hypermethylated genes were used to nominate KEGG pathways related with CSC. As a result, several categories were defined in the KEGG pathways from which most related with cancers, significant and high expression of components was PI3K-AKT signaling pathway. Simultaneously, the AKT activation was also confirmed in the CSCs. The PI3K-Akt signaling pathway should be an important pathway for the CSCs established by the treatment with conditioned medium of LLC cells.

Plasma Neutrophil Gelatinase Associated Lipocalin (pNGAL) Level to Identify AKI Early in Patients Undergoing Cardiac Valve Surgery

Cardiac valve surgery is considered one of the most frequent surgical procedures in which AKI is a common & serious complication. Although serum creatinine is routinely used as a marker of renal function, it poorly reflects the immediate post operative period renal function. Within minutes to few hours after a renal insult, plasma neutrophil gelatinase associated lipocalin (pNGAL) is released. The aim of this study was to assess the superiority of pNGAL over serum creatinine in detecting AKI in early post operative period. This prospective observational study was carried out in the Department of Nephrology of National Institute of Kidney Diseases & Urology in collaboration with National Institute of Cardiovascular Diseases (NICVD) & Dhaka Shisu Hospital (DSH) from January 2015 to December 2016. Total 120 patients were selected from inpatient ward of cardiovascular surgery department. According to inclusion & exclusion criteria total 80 patients were included who was undergone cardiac valve surgery. Serum samples for pNGAL were collected from study population 6 hours after completion of surgery & stored at -80°C, serum samples were also collected for serum creatinine day before surgery, in 1st post operative day (POD1) & 2nd post operative day (POD2). Total 79 patients undergoing cardiac surgery, who met the inclusion & exclusion criteria, were consecutively included. There were 44 male (55.69%) and 35 female (40.31%) ranged from 15-60 years, with mean age of 36 years. pNGAL level in the blood of AKI patients (244.19±59.61ng/ml) 6 hours after completion of surgery was significantly higher from the non AKI patients (171.73±68.63ng/ml). A positive significant correlation was found between pNGAL 6 hours after completion of surgery & serum creatinine at POD1, POD2. This study demonstrated that level of pNGAL concentration 6 hours after completion of cardiac valve surgery increased before the rise of serum creatinine level & can thus AKI can be detected earlier by pNGAL.

Participation of leukotriene C(4) in the regulation of suicidal erythrocyte death

Eryptosis, the suicidal death of erythrocytes, is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the erythrocyte surface. Eryptosis is triggered by increase in cytosolic Ca(2+) concentration upon energy depletion. The present study explored the involvement of leukotrienes. Western blotting was employed to detect the cysteinyl-leukotriene receptor cysLT1, competitive immune assay to determine leukotriene release from erythrocytes, Fluo3 fluorescence to estimate cytosolic Ca(2+) concentration, forward scatter to analyse cell volume and annexin V-binding to disclose phosphatidylserine exposure. As a result, erythrocytes expressed the leukotriene receptor CysLT1. Glucose depletion (24 hours) significantly increased the formation of the cysteinyl-leukotrienes C(4)/D(4)/E(4). Leukotriene C(4) (10 nM) increased Ca(2+) entry, decreased forward scatter, activated caspases 3 and 8, and stimulated annexin V-binding. Glucose depletion similarly increased annexin V-binding, an effect significantly blunted in the presence of the leukotriene receptor antagonist cinalukast (1 microM) or the 5-lipoxygenase inhibitor BW B70C (1 microM). In conclusion, upon energy depletion erythrocytes form leukotrienes, which in turn activate cation channels, leading to Ca(2+) entry, cell shrinkage and cell membrane scrambling. Cysteinyl-leukotrienes thus participate in the signaling of eryptosis during energy depletion.

Development of an odd-Z-projectile reaction for heavy element synthesis: 208Pb(64Ni,n)271Ds and 208Pb(65Cu,n)(272)111

Seven 271Ds decay chains were identified in the bombardment of 208Pb targets with 311.5 and 314.3 MeV 64Ni projectiles using the Berkeley Gas-filled Separator. These data, combined with previous results, provide an excitation function for this reaction. From these results, an optimum energy of 321 MeV was estimated for the production of (272)111 in the new reaction 208Pb(65Cu,n). One decay chain was observed, resulting in a cross section of 1.7(+3.9)(-1.4) pb. This experiment confirms the discovery of element 111 by the Darmstadt Group who used the 209Bi(64Ni,n)(272)111 reaction.

Attitudes and practices of postgraduate medical trainees towards research--a snapshot from Faisalabad

OBJECTIVE

To assess the attitudes and practices of postgraduate medical trainees towards research.

METHODS

It was a self-administered questionnaire based cross-sectional survey conducted on 55 conveniently selected trainees in Allied Hospital, Faisalabad.

RESULTS

Only 11 trainees read journals monthly, seven had written an article for a journal, 51 regarded reading literature important, 39 intended to engage in future research and 37 said they received inappropriate research training. The major reasons cited for poor research activity in Pakistan were poor research training and awareness.

CONCLUSION

Though the attitudes towards research were positive, they were deficient practically in terms of reading and writing literature. There is an immediate need to improve research training in our educational institutes to facilitate the development of the local literature both in terms of research utilization and production

Cardiovascular health--behaviour of medical students in Karachi

OBJECTIVE

To assess the health behaviour and perceptions of medical students towards cardiovascular disease.

METHODS

This descriptive cross-sectional survey was conducted on 203 Pakistani medical students enrolled in a private medical college in Karachi, Pakistan using systematic random sampling. It was based on a self-administered questionnaire.

RESULTS

Eight percent smoked, 9% were overweight, 33% had a family history of coronary artery disease, 32% regulated dietary fat intake, 28% exercised regularly, 62.1% knew personal blood pressure and 5.4% personal cholesterol levels. Regarding developing cardiovascular disease in the future, 62% showed concern but only 54% of these adopted preventive practices. About 46% believed medical college life had a harmful effect on their health. Gender, family history and personal health status perception were behavior modifying influences (p<0.05). Reasons reported for their behavior were: no need of prevention at their age (38.3%) and never thinking about these issues (37.0%).

CONCLUSIONS

The study shows a high prevalence of coronary artery disease family history, inappropriate dietary intake, physical inactivity; poor screening practices and lack of awareness. The results underscore the urgent need to promote preventive knowledge and practices among medical students, if they are to become prevention oriented physicians and counsel patients on preventive strategies to counter the rapidly increasing burden of cardiovascular diseases effectively.

The hemicholinium-3 sensitive high affinity choline transporter is internalized by clathrin-mediated endocytosis and is present in endosomes and synaptic vesicles

Synthesis of acetylcholine depends on the plasma membrane uptake of choline by a high affinity choline transporter (CHT1). Choline uptake is regulated by nerve impulses and trafficking of an intracellular pool of CHT1 to the plasma membrane may be important for this regulation. We have generated a hemagglutinin (HA) epitope tagged CHT1 to investigate the organelles involved with intracellular trafficking of this protein. Expression of CHT1-HA in HEK 293 cells establishes Na+-dependent, hemicholinium-3 sensitive high-affinity choline transport activity. Confocal microscopy reveals that CHT1-HA is found predominantly in intracellular organelles in three different cell lines. Importantly, CHT1-HA seems to be continuously cycling between the plasma membrane and endocytic organelles via a constitutive clathrin-mediated endocytic pathway. In a neuronal cell line, CHT1-HA colocalizes with the early endocytic marker green fluorescent protein (GFP)-Rab 5 and with two markers of synaptic-like vesicles, VAMP-myc and GFP-VAChT, suggesting that in cultured cells CHT1 is present mainly in organelles of endocytic origin. Subcellular fractionation and immunoisolation of organelles from rat brain indicate that CHT1 is present in synaptic vesicles. We propose that intracellular CHT1 can be recruited during stimulation to increase choline uptake in nerve terminals.

Infant growth patterns in the slums of Dhaka in relation to birth weight, intrauterine growth retardation, and prematurity

BACKGROUND

Relations between size and maturity at birth and infant growth have been studied inadequately in Bangladesh, where the incidence of low birth weight is high and most infants are breast-fed.

OBJECTIVE

This study was conducted to describe infant growth patterns and their relations to birth weight, intrauterine growth retardation, and prematurity.

DESIGN

A total of 1654 infants born in selected low-socioeconomic areas of Dhaka, Bangladesh, were enrolled at birth. Weight and length were measured at birth and at 1, 3, 6, 9, and 12 mo of age.

RESULTS

The infants' mean birth weight was 2516 g, with 46.4% weighing <2500 g; 70% were small for gestational age (SGA) and 17% were premature. Among the SGA infants, 63% had adequate ponderal indexes. The mean weight of the study infants closely tracked the -2 SD curve of the World Health Organization pooled breast-fed sample. Weight differences by birth weight, SGA, or preterm categories were retained throughout infancy. Mean z scores based on the pooled breast-fed sample were -2.38, -1. 72, and -2.34 at birth, 3 mo, and 12 mo. Correlation analysis showed greater plasticity of growth in the first 3 mo of life than later in the first year.

CONCLUSIONS

Infant growth rates were similar to those observed among breast-fed infants in developed countries. Most study infants experienced chronic intrauterine undernourishment. Catch-up growth was limited and weight at 12 mo was largely a function of weight at birth. Improvement of birth weight is likely to lead to significant gains in infant nutritional status in this population, although interventions in the first 3 mo are also likely to be beneficial.

[Surgery of esophageal cancer]

In the last 12 months 40 patients underwent surgery for carcinoma of the esophagus. In 18 cases the tumor was located in the lower third of the esophagus. An abdomino-thoracic approach was employed and a 2/3 resection of the esophagus and an esophagogastrostomy were performed. The resected area was bridged by an isoperistaltic gastric tissue tube and anastomosis was carried out using the EEA stapler. A telescope antirefluxplasty was performed to protect the anastomosis and to prevent a gastroesophageal reflux. One patient died of pneumonia. In all cases a secure anastomosis was achieved and in most cases gastroesophageal reflux was prevented.