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R Faris

Publications and source records attributed to R Faris.

At least 19 recordsLinked to original sources
PubMed1997

Antigenic phenotypes common to rat oval cells, primary hepatocellular carcinomas and developing bile ducts.

The shared expression of monoclonal antibody-defined antigens by oval cells and by bile ducts, neoplastic nodules and primary hepatocellular carcinomas (PHC) has provided support for the ability of oval cells to undergo differentiation along ductular or hepatocyte lineages and/or to progress to hepatocellular carcinoma. With the aim of obtaining additional insight into this process, we have combined serial section and double labeling immunofluorescence analysis to determine if phenotypes expressed in vitro by four rat oval cell lines and the H5D.61 hepatocellular carcinoma cell line and in situ by ethionine-induced primary hepatocellular carcinomas reproduce antigenic patterns occurring during normal liver development. Analysis using monoclonal antibodies specific for the oval cell antigens OV6 and OC.2 and hepatocyte markers HBD.1 and H.4 defined subpopulations in four oval cell lines and neoplastic hepatocytes in PHC and H5D.61 with OC.2-/OV6+ and OC.2+/OV6+ phenotypes. Cells with an OC2+/OV6- phenotype were rarely observed in cell lines or primary tumors. In contrast, areas composed of OV6+/H.4+ cells were frequently found in PHC. Examination of fetal and neonatal rat livers demonstrated the stage-specific appearance of three of these phenotypes during liver development. The OC.2+/OV6- phenotype appeared transiently prior to embryonic day (ED) 18 in a subpopulation of HBD.1+ hepatoblasts. OV6 expression was first detected at ED18 on developing bile ducts that were negative for OC.2. These newly formed ducts rapidly acquired OC.2, starting with ducts in the hilar region and spreading outward towards the periphery. This OC.2 expression gradient persisted in the newborn rat liver but became more skewed towards doubly positive cells, with OC.2-/OV6+ cells being found primarily in the periphery. Hepatocytes expressing both OV6 and H.4 were not observed in fetal liver but appeared in neonatal liver in close proximity to OV6+ interlobular ducts. From these findings, it was concluded that oval cells and PHC display phenotypes representing normal stages in liver development, suggesting that oval cells and cells within ethionine-induced PHC are capable of initiating but are unable to complete pathways of hepatocytic or biliary differentiation.

Animals↗
PubMed1997

Evaluation of a stage-specific proteolytic enzyme of Schistosoma mansoni as a marker of exposure.

Cercarial elastase (CE) is one of the first proteins released in the host by invading schistosome cercariae. An enzyme-linked immunosorbent assay (ELISA)-formatted immunoassay has been developed to detect antibodies to the stage-specific CE antigen of Schistosoma mansoni as marker of exposure. We have evaluated this test system as an epidemiologic tool, using well-characterized sera collected from S. mansoni- and S. haematobium-infected subjects residing in endemic areas and from control subjects living in nonendemic areas in Egypt. Urine, stool specimens, and blood samples were collected from a sample of 272 endemic subjects randomly selected to represent different age groups in the range of 2-20 years of age. Of 47 S. mansoni-infected subjects, 41 (87.2%) had anti-CE IgG antibodies. Of 52 S. haematobium-infected cases, 38 (73.0%) had IgM antibodies to CE and 43 (82.7%) had IgG antibodies to CE. Of 173 egg-negative people in the endemic area, 84 (48.6%) were IgM positive and 99 (57.2%) were IgG positive. The mean IgM and IgG antibody levels were similar in the infected groups but were significantly lower in the egg-negative group (P = 0.001). All sera from young children (2-3 years of age) were uniformly ELISA negative. The prevalence of IgM and IgG antibodies to CE in children less than six years of age were significantly lower than in other age groups. There was no significant difference in prevalence rates of IgM and IgG anti-CE antibodies between subjects having other parasites present in the endemic area (Ascaris lumbricoides, Entrobius vermicularis, Hymenolepis nana, H. diminuta, Trichostrongylus spp., and Entamoeba histolytica) and those without any parasitic infection. All nonendemic sera (58), including those with other helminth infections, were uniformly ELISA negative for antibodies to CE. These findings suggest that antibodies to elastase indicate exposure, but not necessarily active schistosome infection.

Adolescent↗
PubMed1997

Selenium levels in breast milk and cow's milk: a preliminary report from Saudi Arabia.

We measured the selenium in 117 milk samples by means of inductively coupled plasma spectrometry with the hydride t-system. The samples were collected from healthy lactating mothers living in the Al-Kharj area in Saudi Arabia and from seven brands of Saudi fresh cow's milk. The concentration of selenium in breast milk significantly decreases toward the end of lactation. Our results also showed that the selenium concentration in breast milk is also influenced by the number of breast feedings per day. Further studies are needed to evaluate the selenium status in Saudi infants. The selenium concentration in local cow's milk samples was significantly higher than in the breast milk samples.

Adolescent↗
PubMed1997

Filariasis transmission potential of mosquitoes to humans of different age groups.

Age-specific levels of Wuchereria bancrofti infection determined by microfilaremia in filarious 10 to 60 years old males from endemic village revealed that microfilaria intensity was higher in younger age, presumably because of increased vector biting rate of younger individuals. Out of 1334 Cx. pipiens captured while attempting to bite 51 child-adult bait pairs, 54.0% selected a host in the 10-15 age group. Biting preference towards children was more evaluated (79.2%) later than earlier in the night. Frequency distribution of age-specific biting collections indicated that 62.7% recorded exceeding numbers of bites on children, 21.6% adult biting, and 15.7% equal biting of one of the baits in the pair. Furthermore, 21.6% of the children were exposed to nightly bites ranging from 21 to 64 and only 7.8% of the adults experienced from 21 to 85 bites. Mosquito biting intensity averaged 14.2 and 11.6 bites/night for children and adults respectively. Children experienced 22.4% more bites per night than adults. Thus, children are more exposed to filaria infection and seem to represent an important source of infection. It is concluded that attempts at widespread control of filariasis in the densely populated Nile Delta, where youngsters may account for an immense proportion of the local population, should concentrate on immatures.

Adolescent↗
PubMed1996

Glutamine-enriched total parenteral nutrition enhances plasma glutathione in the resting state.

Glutathione (GSH) is the major intracellular antioxidant and is essential to normal cell function and replication. Cysteine and other thiol compounds have been considered rate-limiting for GSH biosynthesis, but recent studies have demonstrated that glutamine (GLN) becomes essential during metabolic stress to replete tissue GSH levels which have become depleted. To determine the role of GLN supplementation in the resting, nonstressed state, we studied three groups of Wistar rats. The animals were catheterized and randomly assigned to one of three groups; (1) chow ad libitum group receiving iv saline (control), (2) standard total parenteral nutrition (STA-TPN) group, and (3) glutamine-enriched TPN (GLN-TPN) group. The intravenously fed animals received no rat chow. The infusions were administered at a rate of 2.2 ml/hr for 4 days and all animals were harvested on the fifth day of study. The GLN-TPN group had a significantly higher plasma GSH level than STA-TPN or control animals (P < 0.01). The hepatic concentration of GSH and the oxidized GSH/reduced GSH were similar in all groups. GLN-TPN had a significantly lower plasma ALT level than the control group (P < 0.05). The control group had a significantly higher ALP level than STA-TPN and GLN-TPN animals (P < 0.01). There were no significant differences in other measures of hepatic functions among the three groups. Our data demonstrate that in this model GLN-enriched TPN enhances plasma GSH concentrations, while maintaining hepatic GSH stores. This suggests that GSH turnover is altered during glutamine-enriched TPN, which may explain how dietary GLN supplementation enhances tissue antioxidant capacity.

Animals↗
PubMed1996

The enhanced effect of parenteral nutrition on hepatotoxicity.

Recent studies have demonstrated that enteral feedings are associated with decreased morbidity and mortality when compared with parenteral feedings. In this study, we hypothesized that (1) route of feeding affects morbidity and mortality in a model of drug-induced hepatotoxicity and (2) glutamine and polymyxin B, which have been reported to reduce bacterial translocation, attenuate this effect when TPN is used. Male virus-free Wistar rats were divided into six groups receiving: (1) ad libitum chow infused with intravenous (IV) saline (Chow), (2) standard total parenteral nutrition solution administered via gastrostomy (Enteral), (3) standard total parenteral nutrition infused via a central catheter (TPN), (4) standard TPN containing polymyxin B (TPN-PolyB), and (5) glutamine-enriched TPN (TPN-GLN). A final group of animals was not manipulated but harvested at time 0 to serve as controls. The dose of polymyxin B used in this study has previously been shown to significantly reduce bacterial translocation. After 4 d of feeding, all rats received 5% dextrose infusion after an intraperitoneal (IP) injection of acetaminophen (ACM). Rats were sacrificed 0, 6, and 24 h after ACM administration. The TPN group had a lower liver glutathione level after 6 and 24 h, greater levels of liver enzymes after 24 h, and a lower survival rate after 24 h compared with Chow. The Enteral group had less morbidity than TPN but greater morbidity than Chow. Addition of polymyxin B or glutamine had a minimal effect on morbidity or mortality when compared to the TPN group. We conclude that rats receiving IV nutrition have greater morbidity and mortality following a standard hepatic insult than chow-fed rats. We speculate that alteration of microsomal cytochrome P-450 or drug clearance may be related to the benefits of providing nutrients by the gastrointestinal route.

Acetaminophen↗
PubMed1996

Insulin-like growth factor II blocks apoptosis of N-myc2-expressing woodchuck liver epithelial cells.

N-myc2 and insulin-like growth factor II (IGF-II) are coordinately overexpressed in the great majority of altered hepatic foci, which are the earliest precancerous lesions observed in the liver of woodchuck hepatitis virus carrier woodchucks, and these genes continue to be overexpressed in hepatocellular carcinomas (HCCs). We have investigated the function of these genes in woodchuck hepatocarcinogenesis by using a woodchuck liver epithelial cell line (WC-3). WC-3 cells react positively with a monoclonal antibody (12.8.5) against woodchuck oval cells, suggesting a lineage relationship with oval cells. Overexpression of N-myc2 in three WC-3 cell lines caused their morphological transformation and increased their growth rate and saturation density in medium containing 10% serum. Removal of serum from the medium increased cell death of the N-myc2-expressing lines, whereas cell death in control lines was minimal. The death of N-myc2-expressing WC-3 cells was accompanied by nucleosomal fragmentation of cellular DNA, and DAPI (4',6-diamidino-2-phenylindole) staining revealed condensation and fragmentation of the nuclei, suggesting that N-myc2-expressing WC-3 cells undergo apoptosis in the absence of serum. In colony regression assays, conducted in the absence of serum, control colonies were stable, while N-myc2-expressing colonies regressed to various degrees. Addition of recombinant human IGF-II to the serum-free medium blocked both cell death and colony regression in all the N-myc2-expressing lines. Therefore, coordinate overexpression of N-myc2 and IGF-II in woodchuck altered hepatic foci may allow cells which otherwise might die to survive and progress to hepatocellular carcinoma.

Animals↗
PubMed1996

High seroprevalence of hepatitis A, B, C, and E viruses in residents in an Egyptian village in The Nile Delta: a pilot study.

Hepatitis C virus (HCV) infection is hyperendemic in Egypt, with seroprevalence rates of 10-20% among volunteer blood donors, and even higher rates reported among segments of the general population. We attempted to confirm the high seroprevalence of HCV and to compare it with the age-specific seroprevalence rates for hepatitis A, hepatitis B, and hepatitis E among 155 nonrandomly selected residents of a semiurban village in the Nile River delta. Of the two orally transmitted viruses (HAV and HEV), all 1-3-year-old children had been infected by HAV and the seroprevalence rate of 100% persisted until age 67. In contrast, HEV infections were not detected until children were 4-9-years old, and the 57% seroprevalence rate in this age group did not increase appreciably in older age groups. Of the two parenterally transmitted viruses, HBV was first detected in 1-3-year-olds, whereas HCV was first detected later, in 10-19-year-olds. The seroprevalence rates of both viruses increased progressively with age, peaking in the 40-67-year-old group at 66% for HBV and at 51% for HCV. The number of persons who had only one infection, or no infection at all, was too small to allow meaningful statistical analysis of serologically pure groups infected only by HBV, HCV, or HEV. The results of this pilot study revealed extraordinarily high seroprevalence rates of HBV, HCV, and HEV in this village, and distinctive age-specific seroprevalence rates suggesting different patterns of transmission.

Adolescent↗
PubMed1996

Parasite antigenemia without microfilaremia in bancroftian filariasis.

The term "endemic normal" in the context of filariasis refers to people who are amicrofilaremic and free of clinical signs or symptoms of filariasis despite regular exposure to the parasite. Some sera from endemic normals contain soluble Wuchereria bancrofti antigens that are detectable by enzyme-linked immunosorbent assay. We now report evidence that filarial antigenemia in these people is not an artifact and that it is indicative of active W. bancrofti infection. Filarial antigenemia was first detected within one month of the onset of microfilarial patency in experimentally infected primates. Human sera from antigen-positive endemic normals contained the same filarial antigens (by Western blot) as sera from people with microfilaremia. Sera from antigen-positive endemic normals also contained significantly higher levels of immunoglobulin G4 antibodies to native and recombinant filarial antigens than sera from antigen-negative controls matched for age and sex. The epidemiology of filarial antigenemia in endemic normals was studied with sera from a population-based study of filariasis in an Egyptian village with a microfilaria prevalence of 29%. Seventeen percent of endemic normals had antigenemia, and this group comprised 11% of the total village sample. Filarial antigenemia was significantly more common in endemic normals more than 30 years of age than in younger people. These results suggest that amicrofilaremic and asymptomatic W. bancrofti infections are relatively common in endemic areas. Additional studies are needed to determine the clinical significance, prognosis, and optimal management of such infections.

Adolescent↗
PubMed1994

Characterization and enrichment of fetal rat hepatoblasts by immunoadsorption ("panning") and fluorescence-activated cell sorting.

We developed methods for enriching fetal hepatoblasts by combining panning and multiparametric fluorescence-activated cell sorting. In unpurified, dissociated fetal liver cell suspensions of embryonic age day 15, 3.2% +/- 1.3% and 2.5% +/- 0.7% cells expressed albumin and alpha-fetoprotein, respectively. The remainder exhibited a hemopoietic, endothelial or stromal cell phenotype. Cells were panned first with an antibody to red blood cells to remove erythroid cells and then with monoclonal antibodies OX-43/OX-44 to remove hemopoietic and endothelial cells. This procedure eliminated 84% of fetal hepatic cells, with enrichment of the remainder for albumin or alpha-fetoprotein expression (up to sixfold increase). Flow cytometric analysis of unlabeled cells revealed two populations, which differed in granularity and autofluorescence. After panning, fluorescence-activated cell sorting for agranular cells yielded OX-43/44-positive cells that were essentially all hemopoietic precursor cells or OX-43/44-negative cells that were mostly hemopoietic precursor cells, along with 3.0% +/- 0.7% alpha-fetoprotein-positive cells. In contrast, sorting for granular, OX-43/44-negative cells enriched for predominantly alpha-fetoprotein-positive, parenchymal precursor cells (75.1% +/- 4.7%). Multiparametric flow cytometric analysis of the expression of an oval cell antigen, OC.3, which is a bile duct and putative liver stem cell marker, showed that most OC.3-positive cells coexpressed OX-43/OX-44 and morphologically were hemopoietic precursor cells. However, approximately 30% of the OX-43/44-negative, granular cells expressed OC.3. Although the physiological significance of OC.3-positive hepatoblasts remains to be determined, the ability to isolate distinct liver cell populations by means of fluorescence-activated cell sorting should facilitate further studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1994

Study of the knowledge, attitude of Egyptian health care workers towards occupational HIV infection.

Acquired immuno-deficiency syndrome (AIDS) was reported for the first time in Egypt in 1986. Up to March 1993, 60 cases were notified to the Ministry of Health and 359 were detected to be infected with human immunodeficiency virus (HIV). Most cases had acquired infection abroad through blood, blood products or sexual contact. The number of cases is continuously increasing. Fear and ignorance about HIV infection causes panic among health care workers (HCWs) whenever a case is discovered and needs medical care. We assessed the knowledge and attitude of 346 HCWs towards the probability of occupational HIV infection using a self administered questionnaire. The sample included physicians, surgeons, nurses, laboratory technicians and ambulance workers. 72.8% of HCWs believed that they are in "great" danger of acquiring AIDS through occupational exposure, whereas 0.6% thought that there was no danger. 67% of HCWs had wrong ideas about transmission of HIV (toilet seats, droplet infection, touching patients). 83.5% mentioned that AIDS patients should be isolated in quarantine. The main source of information about AIDS was the television, radio and ordinary press. 44.8% got their information from textbooks or scientific literature. 95.4% felt the need for more information about infection and disease. The results show an urgent need to start a program of education of HCWs concerning the risk of occupational HIV infection and the measures of its prevention.

Attitude of Health Personnel↗
PubMed1993

The resurgence of lymphatic filariasis in the Nile delta.

A study of 325,000 residents of 314 villages in six governorates of the Nile delta area of Egypt revealed that the prevalence of lymphatic filariasis increased from < 1% in 1965 to > 20% in 1991, especially in the governorates of Qalyubiya, Monufiya, Dakhaliya, and Giza. The distribution of the communites with endemic filariasis is focal. Clusters of villages with high prevalences are surrounded by others in which the disease is absent, although their environmental, social, and agricultural features appear similar. The article analyses why the significant decline in filariasis between 1945 and 1965 in Egypt has been followed by a resurgence of the disease.

Animals↗
PubMed1992

Child abuse as an inhibiting factor for family planning.

The aim of this study is to determine the magnitude of the problem of using children as an economic asset to the family thus, in one way increasing the prevalence of child abuse in Egypt and also hindering the family planning program. Two focus-group interviews were conducted in urban & rural areas for 10 women with the same age range and socioeconomic background. All were non-users of any contraception. Subsequently an interview was conducted for all women who attended the Ob. & Gyn. Clinic at Ain Shams University Hospital in the period from June to August 1991, their ages ranged from 30-35 years and they never used contraception. Another group of women with the same characteristics were interviewed from a rural area at Fayoum Governorate. A questionnaire was filled for each interviewed woman. The total women interviewed in urban area is 340 while in the rural area they were 400 women. Sixty percent of urban women and 80% of rural women are illiterate, 70% of the urban & 100% of rural women are housewives. Their years of marriage ranged between 10-20 years and all of them have more than five children. A percentage of 73.5% of urban women and 85% of rural women stated that children are used as an economic asset to their families, they work in urban areas as assistants in motor repairs, hair-dressers, beggars, bakeries, shops, restaurants and factories while in rural areas they work as agricultural workers.

Adult↗
PubMed1991

Blood lead level of Cairo traffic policemen.

Blood lead level, haemoglobin concentration (Hb) and urinary delta-aminolevulenic acid (ALA) were determined for 126 traffic policemen and a control group of 50 office-based policemen of Cairo city. Mean blood lead level and Hb of traffic policemen were significantly higher than those of the controls; ALA of both groups were similar. The blood lead level of traffic policemen was not related to age, duration of employment or Hb. Although the observed blood lead level of Cairo traffic policemen (29.2 +/- 7.5 microns dl-1) may be considered acceptable for their occupation, it indicates a potential risk from traffic-exhaust-induced air pollution for other groups of the Cairo population such as children and pregnant women.

Adult↗
PubMed1991

Evaluation of a monoclonal-antibody based antigen assay for diagnosis of Wuchereria bancrofti infection in Egypt.

Conventional methods for diagnosis of Wuchereria bancrofti infection are insensitive and often impractical because of the need for night blood collections. A sensitive and specific antigen detection assay has been developed for W. bancrofti, which is based on a monoclonal antibody (AD12) that binds to a repeated epitope on a 200 kDa adult worm excretion product present in sera from infected humans. The only formal evaluation of this assay to date was performed with sera from India. In the present study, we have evaluated the performance of the AD12 antigen assay in two laboratories with sera collected in endemic and non-endemic areas in Egypt. Antigen was detected in 57 of 59 (97%) sera from microfilaremic subjects, and in 22 of 139 asymptomatic and amicrofilaremic subjects who reside in a highly endemic area. Antigen titers were significantly correlated with microfilaria counts (r = 0.41, P less than 0.01). Filarial antigen was not detected in most sera from amicrofilaremic subjects with clinical filariasis. Comparative antigen test results obtained from laboratories in Cairo and St. Louis agreed in 170 of 173 sera tested. Filarial antigen was not detected in sera from Egyptians with no history of residence in filaria-endemic areas. Specifically, nonendemic sera from patients with other parasitic infections (schistosomiasis, fascioliasis, ascariasis, etc.) were uniformly negative in the assay. We conclude that the AD12 filarial antigen assay is sensitive and specific for W. bancrofti infection in Egypt.

Animals↗
PubMed1991

An epidemiologic study of Papanicolaou smear data at Ain-Shams University hospitals.

This study is designed to find out the association between some risk factors for cancer cervix and the sensitivity and specificity of pap smear test. Data from the Cyto-Diagnostic Unit of Department of Obstetrics and Gynaecology Ain-Shams University are used. Women included in the study are those, who have had both cytology and directed biopsies irrespective of the cytology results. 757 women from 1981-1989 met that criteria and data for them are retrieved from computer files. It is found that there is association between age of women (P less than or equal to 0.05 for sensitivity and specificity), parity (P less than or equal to 0.05 for sensitivity, P greater than 0.05 for specificity), age at marriage (P less than 0.05 for sensitivity, P greater than 0.05 for specificity), and duration of marriage (p greater than 0.05 for sensitivity, P less than 0.05 for specificity), and the sensitivity and specificity of Papanicolaou smear.

Adult↗