Antifibrotic effect of curcumin on thioacetamide induced liver fibrosis

The objective of the present study was to elucidate whether serum ATX activity might be a target for regulation of liver fibrosis and to evaluate the hepatoprotective and antifibrotic effect of curcumin in TAA induced liver fibrosis in rats. Therefore 40 healthy adult albino rats, divided into 4 groups [10 rats in each]. Rats in the 2[nd] group received curcumin [500 mg/kg b. wt /orally every day], the 3[rd] group injected by thioacetamide [TAA] intraperioteneal [250 mg/kg b. wt] three times a week, the 4[th] group injected by TAA intraperioteneal [250 mg/kg b. wt] three times a weeks and received curcumin orally [500 mg/kg b. wt every day]. The changes in body weight index and histopathological examination. In addition, selected biochemical parameters were also determined. The present study revealed that, oral supplementation of curcumin causing increase of liver weight index, autotaxin [ATX], HDL-c level and decrease of total protein, urea, creatinine and ammonia, total cholesterol, LDL-c and triacylglycerols. Treatment with TAA induced increase in the liver weight index, ATX, ALT, triacylglycerols, ammonia levels and decrease in serum proteins, urea, total cholesterol, HDL-c and LDL-c levels. Histopathological examination revealed severs necrosis, inflammatory cellular infiltration and nodules in TAA group. While the supplementation of rats with TAA and curcumin orally together resulted in increase in liver weight index, ATX, ALT, triacylglycerols levels and decrease in serum total protein, urea, total cholesterol, HDL-c, LDL-c concentration moreover, revealed mild inflammation and necrosis by histopathological examination. Conclusively, the use of curcumin ameliorated the effect of TAA induced liver fibrosis but cannot reach the normal levels

Influence of combined administration of turmeric and black seed on selected biochemical parameters of diabetic rats

The objective of the present study was to investigate the effect of Turmeric [Curcuma Longa] and Black cumin seed [Nigella Sativa] mixture on selected biochemical parameters of streptozotocin [STZ] induced diabetic rats. Therefore, twenty one healthy adult albino rats divided into three groups [7 rats in each]. Rats of first and second groups were non diabetic and diabetic respectively. Rats of the third group were diabetic and received a mixture of Turmeric [0.5 g/kg b .wt.] and Black cumin seed [1 g/kg b.wt.] orally by intragastric intubations once a day for six weeks. The changes in blood glucose level, body weight and water and food intake were measured. In addition, selected biochemical parameters were also determined. The present study revealed that, dietary supplementation of plant mixture of Turmeric and Black cumin seed to diabetic rats significantly [P<0.05] reduced the blood glucose level as well as water and food intake accompanied by an increase in body weight gain when compared with untreated diabetic rats. Proteins were not affected whereas liver and kidney functions were disrupted in STZ-diabetic rats and restored whenever treated by medicinal plants mixture. Hypercholesterolemia and hyperlipidemia observed in STZ-diabetic rats were attenuated by administration of examined medicinal plants combination. Conclusively, dietary supplementation of Turmeric and Black cumin seed mixture reduced blood glucose level and ameliorated the hypercholesterolemia and hyperlipidemia in STZ induced diabetic rats

Gene mutations in Wilson disease in Egyptian children: report on two novel mutations

Wilson disease [WD] is an autosomal recessive disorder, caused by defects in copper-transporting P-type adenosine triphosphatase [ATPase] encoded by the ATP7B gene, resulting in the deposition of copper in the liver and brain with significant disability or death if left untreated. An available regimen of treatment gives hope to those predisposed to the disease if diagnosed early. The objective of this study was to determine the frequency of the most common European mutation [p.H1069Q] in Egyptian children with WD, in addition to screening for previously reported mutations in the Egyptian patients in our selected group. Direct DNA sequencing was applied to exons [13, 14, 18, and 19] of the ATP7B gene for 19 patients previously diagnosed with WD. Then DNA sequencing and pedigree analysis were performed in the families of the patients showing variations in their results for the purpose of family screening and carrier detection. Six out of 19 patients were studied with their families [three families]. We identified five variants of which two were novel among the studied patients. One of the novel variants was synonymous substitution [p.A1074A] in 16% of patients and the other was predicted to be missense disease-causing mutations [p.T1076I] in 16% of patients, and three previously published mutations p.H1069Q were detected in 5% of patients, p.P1273Q in 10% of patients, and a silent variant p.A1003A in 26% of patients. Screening for the two exons 14 and 18 of the ATP7B gene is important in Egyptian patients especially in suspected patients without hepatic manifestations

Effect of sesame oil on serum and liver lipid profile in hyperlipidemic rats

This study was conducted to investigate the effect of sesame oil on serum and hepatic Iipid profile in induced hyperlipidemic rat .Eight forty rats were randomly divided into equal six groups of eight animals each for 30 days as follows: The first group [control] was kept on basal diet and water, the second group was kept on basal diet added to it sesame oil [SSO]5%, the third group was given a basal diet supplemented by SSO10%,the fourth group [hyperlipidemic] ,hyperlipidemia was induced at last two weeks by intra peritoneal injection of Triton WR1339 [200mg/Kg, /three times /week] ,fifth group was fed basal diet +i.p of Triton 200mg/Kg +SSO5%,the six group was kept on basal diet +i.p injection of same dose of Triton +SSO10% . Blood samples were collected and serum was separated for determination of the followings triglycerides, cholesterol, HDL[high density lipioprotin], LDL[low density lipoprotein],VLDL [very low density lipoprotein], ALT[Alanin aminotrancferase],AST[Aspartate aminotransferase],GGT [garnrna glutamyl tranferase], ALP [Alkaline phosphatase] ,hepatic Iipid profile, thyroid hormones and adiponectin hormone. Induction of hyperlipidema resulted in a significant elevation of all parameters except HDL, adiponectin and thyroid hormones not significant decrease compared to control group .supplementation with sesame oil 5% and SSO 10% signaficantly decrease in all serum and hepatic Iipid profile and liver enzymes while HDL ,adiponectin ,thyroid hormones are elevated . Conclusion: SSO 5% was possess a better improving potential for hyperlipidemia, serum glucose, adiponectin, thyroid hormones, hepatic Iipid profile than SSO 10%

prospective toxic effects of some heavy metals overload in surface drinking water of Dakahlia governorate, Egypt

The concentration of heavy metals in drinking water is very important. To to evaluate the chemistry of some heavy metals in surface drinking water of Dakahlia Governorate, Egypt. 51 surface drinking water samples were collected from the main surface water stations and compact units in October 2009 and analyzed chemically. 26 water samples were analyzed by atomic absorption spectrophotometer for iron, manganese, lead, nickel, chromium, zinc, copper, cobalt, aluminum, and cadmium concentrations. Aluminum concentration was slightly high in water sample of Bosat network. Cadmium concentration in samples of up-streams of shark and Mit-Khamis stations, networks of Mit-Antar, Demera, Bosat, Bilqas, El-satamony, EI-Gamalia, Mit-asim and Bilqas station exceeded the permissible limits of Egyptian Ministry of Health [EMH, 2007] and World Health Organization [WHO, 2008]. The nickel concentration in the network samples taken from Shoha, Bosat and EI-Gamalia as well as up-stream of Bosat station exceeded the permissible limits. Also, lead concentrations of the network samples of Shoha, Mit-Antar, Demera and Nabaru exceeded the permissible limits. Regular chemical analysis of surface drinking water is required. Since these heavy metals are most likely originate from steel, plastics and batteries industries working in the region, we believe that activities of these industries must be stopped or at least limited in urban zones

Cardiac enzymes activities and troponin-1 level in rabbit invested with intestinal and hepatic coccidiosis

This study was performed to elucidate the effect of both intestinal and hepatic coccidiosis on cardiac enzymes, GST, Catalase activities as well as troponine 1 level in rabbits. Furthermore, the study was extended to investigate the activities of the previous parameters after treatment of invested rabbits with coccidiosis. In this study, thirty six male rabbits were divided into 6 groups. Group 1 is a healthy control group. Groups 2, 3, 4, 5 and 6 were design as invested with intestinal type of coccidiosis, infected with hepatic type of coccidiosis, control treated with sulpha drug, infected with intestinal coccidiosis and treated with sulpha drug, infected with hepatic coccidiosis and treated with sulpha drug group, respectively. cardiac enzymes as AST, CPK, CPK-MB and LDH increased than the normal level during coccidial infection, either hepatic or intestinal type but it more pronounced in hepatic one after 7 and 14 days of infection. Also, troponine 1 level was increased significantly in the groups infected with intestinal and hepatic coccidiosis than the control group at 7 and 14 days from infection, whereas GST, Catalase activities decreased significantly in groups infected with either intestinal and hepatic coccidiosis than control one. Pretreatment with sulpha drugs improve the biochemical parameters changed by coccidial infections

Biochemical alteration of some serum constituents in laying hens supplemented by high fat rations

For performing this study, 40 pullets were divided classified into four equal group, one given basal diet only, 2[nd] group kept on basal diet plus beef tallow, 3[rd] group given basal diet plus linseed oil and the last group was supplemented with basal diet and olive oil. Blood samples were collected 4 and 8 weeks post-treatment and the obtained results revealed that the total serum lipids, cholesterol and triacylglycerol, were significantly increased at eight weeks in beef tallow and linseed oil treated group while, they were greatly decreased in olive oil treated group. On the other hand, the serum proteins values were significantly decreased in all treated birds after 8 weeks. The present work provides evidence that all types of lipids used in this work significantly decreased the concentration of serum calcium, phosphorus, magnesium, iron while, most of them increased the serum copper concentration

Drug and substance abuse in refractory epilepsy

Drugs and substances abuse in patients with refractor epilepsy were investigated in this study which includes 924 patients with intractable epilepsy were studied for serum levels of antiepileptic drugs and for drugs and substances abuse. Positive results for abuse were detected in 246 patients [26.62%], 56.5% of them were in the age group 20 - 30 years. Males outnumbered females with a sex ratio 1.46: 1. Cannabis was the first abused drug as it was detected in 29.27% followed by opiates in 21.95%, alcohol in 17.88%, benzodiazepine in 16.26%, tricylic in 8.54%, barbiturates in 6.1%. So, a screening test for drugs and substances abuse must be done in cases with resistant epilepsy even if patients deny the use of them

protective effect of turmeric on iron overload in albino rats

A total of 40 male albino rats were divided into four groups [10 rats each] to study the antioxidant activity and protective effect of Turmeric on iron overload. The first group fed basal diet only and served as a control. Rats of the second group were injected intrapritoneally [I/P] with iron dextran at a dose of 200 mg/kg body weight. once weekly. Rats of the third group fed diet containing 1% turmeric powder while rats of fourth group were received both iron and turmeric with same mentioned dose and route of administration. After the end of experiment [4.5 months], serum was used for photometric determination of iron profile. In addition liver and kidney functions were also estimated. The liver, spleen, testes, heart and kidney were used for determination of iron concentration, lipid peroxidation, glutathione peroxidase activity [GPx], glutathione-s-transferase activity [GST] and reduced glutathione level [G-SH]. The present findings indicated that iron overload caused many adverse effects reflected the significant increase of all serum iron profile, tissue iron deposition and tissue lipid peroxidation than the control groups. Moreover its administration caused marked liver and kidney damage. Iron overload also caused a significant decrease of GPx activity while GST activity and G-SH level were significantly increased in all tissues when compared with the control group. In the contrary administration of turmeric alone induced a significant decrease of serum and tissue iron profile. The powerful antioxidant plants effect of turmeric was reflected on the marked increase of GPx activity, GST activity and reduced glutathione level in all examined tissues except in liver where the activity of GPx and reduced glutathione level were significantly decreased. Although administration of turmeric for very long time induced mild liver damage, its administration during iron overload decreased the highly mentioned toxic effect induced by iron overload in rats

Vitamin D receptor [VDR] gene polymorphism and risk of osteoporosis in Egyptian post menopausal women

Identifying people at risk of osteoporosis is very important, as prevention is possible. Because genetic factors were shown to have a great influence on osteoporosis susceptibility, their study may be of great help in targeting high-risk individuals. In this work, we studied the association between VDR gene polymorphism and bone mineral density in postmenopausal Egyptian females. 45 Egyptian postmenopausal women [57 +/- 4.6 years] were studied. Bone mineral density was measured at the lumbar spines, the hip, and the lower radius using dual energy X-ray absorptiometry. Ten of the studied patients [22%] had osteoporosis [T or z scores < -2.5]; 21 [47%] had osteopenia [T or z scores -1 to -2.5]; and 14[31%] were normal [T or z scores > -1]. Restriction fragment length polymorphisms in the VDR gene were assessed by PCR amplification and digestion with restriction enzymes FokI, BsmI, ApaI, and TaqI recognizing polymorphic sites in these four VDR gene loci. The BsmI Bb genotype distribution was significantly higher in the normal postmenopausal women [42.9%] than osteopenic women [4.8%] [p value < 0.002]. The TaqI [T] allele was significantly higher in the normal group [68.0%] than the osteopenic group [45.0%] and TaqI [t] which was significantly higher in the osteopenic group [55.0%] than the normal group [32.0%] [p=0.031 for both], otherwise, there was no significant difference in the distribution of other VDR genotypes in relation to bone density measurement. The higher distribution of the VDR BsmI Bb and TaqI T genotype in the normal postmenopausal than osteopenic women may reflect a protective role, on the other hand, TaqI t allele may be associated with lower bone mineral density in postmenopausal Egyptian females

Serum levels of matrix metalloproteinases in type II diabetes mellitus

Hyperglycemia is associated with excessive non-enzymatic glycosylation of the glomerular matrix thus contributing to the pathogenesis of diabetic nephropathy. Matrix metallopoteinases [mmp[s]] are responsible for matrix degradation. This study was conducted to unvestigate the potential diagnostic value of serum levels of two of the known mmp[s]], namely mmp-1 and mmp-2 in type ii diabetes and their relationship to vascular complications. This study was concluted on 30 female type ii niddm diabetes mellitus [dm] patients recruited from the diabetic clinic, kasr al aini hospital, cairo university. A control group including 10 apparently healthy age matched females with no family history of diabetes was also studied. All patients were subjected to full history taking and full clinical examination. Laboratory investigations included fasting blood sugar, liver function tests, kidney functions, lipid profiles, glycosylated hemoglobin, according to which, patients were divided into 2 groups, fairly and poorly controlled and microalbuminuria, according to which, patents were divided into with and without diabetic nephropathy. Mmp-1 and mmp-2 were measured using an elisa technique. The ages of the patients under study ranged from 40-55, with a mean of 48.83 +/- 4.36. The duration of diabetes ranged between 1-20 years with a mean of 110-170 with a mean of 129.33 +/- 18.56 and their diastolic blood pressure ranged from 60-110 with a mean of 79.33 +/- 8.68. The mean serum mmp-1 level was significantly higher 16.63 +/- 9.13 and 5.48 +/- 2.37 respectively [p= < 0.01]. Mmp-1 was significantly higher in patients with nephropathy compared to controls, however it was significantly decreased than its mean value in patients without nephropathy 14.3 +/- 8.55 and 21.3 +/- 8.83 respectively [p= < 0.05]. The mean serum mmp-1 level was significantly higher in the poorly controlled and fairly controlled diabetics [16.71 ng/ml +/- 9.23 and 16.52 ng/ml +/- 9.37] as compared to the control group [5.48 ng/l +/- 2.37] [p= < 0.01]. The mean serum mmp-1 was significantly higher in the hypertensive group compared with control group 13.49 +/- 8.52 and 5.48 +/- 2.37 respectively [p= < 0.01]. On the other mean serum mmp-2 level was significantly reduced in hypertensive cases compared to the non-hypertensive ones 197.4 +/- 56.76 and 24.741 +/- 57.53 respectively [p= < 0.05]. The mean mmp-2 levels also showed a positive correlation with the diastolic blood pressure [r=0.756, p< 0.01]. Mmp-1 serum levels may be implicated in the complications of DM

Correlation study between cord blood trace elements and anthropometric measures of the newborn

This work was designed to assess the serum zinc and copper levels in pregnant Egyptian ladies at delivery and in their corresponding offspring as well as to study the effects of these elements on intrauterine fetal growth. Thirty full term small for gestational age neonates [SGA] were studied together with their mothers at delivery. They were compared to thirty eight full term appropriate for gestational age [AGA] neonates as well as their mothers. Mothers of both groups of studied neonates were compared to 20 non pregnant ladies as regards serum zinc and copper level. All cases and controls were subjected to detailed history taking from mothers and all deliveries were attended. All babies were examined to exclude acute and chronic complications. Anthropometric measurements were taken at birth. Laboratory investigations including assessment of serum zinc and copper levels by atomic absorption spectrophotometry were performed. The results proved that serum zinc levels were significantly lower in the group of SGA babies as well as their mothers than the group of AGA babies and their corresponding mothers. Similarly, both groups of delivered mothers had significantly lower zinc level than non pregnant ladies. Study of the copper levels in mothers and their neonates showed a tendency to increased levels beyond the normal upper limit in the group of both mothers of SGA and AGA babies with no such increase in their neonates. Our study confirmed that zinc status of mothers during pregnancy strongly affects the intrauterine growth of fetuses. This effect was mainly on weight, resulting in retardation of their growth in cases of mothers who suffered form hypozincemia. The end result was delivery of small for gestational age babies

Effect of divergent selection for 8-week body weight on some productive and reproductive traits in Alexandria chickens

2-way selection for body weight was continued in Alexandria chickens for 6 breeding seasons to evaluate direct responses in 8-week body weight, correlated response on some productive and reproductive traits and to obtain estimates of genetic parameters for the considered traits. The results of the study showed that, male and female 8-week body weights in high line were significantly more than the corresponding weights of both low and Fayoumi lines, as a direct response. The upward selection improvement in age and weight at sexual maturity, egg number and weight. Negative correlated response was marked in fertility% compared to the other 2 lines [P <0.05]. Paternal heritability estimates for the studied traits in higher line was medium to high [>0.22] except hen age at sexual maturity and hatchability%. On the contrary, those of the low line were low heritable [<0.15] except fertility%, viability% and male body weight at 8 weeks. Most of the genetic correlations in high line were positive, but viability% was negatively correlated with male and female 8-week body weigh, hen age at sexual maturity and hatchability% [<0.4] and hen age at sexual maturity was negatively associated with egg number, fertility% and hatchability% [-0.3 to -0.57]

Production of highly immune transgenic chickens by injection of quail bursal DNA

The aim of this work was to produce highly immune transgenic chicks. On the 3rd day of incubation, 4 groups of eggs/breed [Golden Montazah and Gimmizah] were inoculated with quail bursal DNA at the levels [10, 20, 40 and 80 mug/egg]. A fertility of the DNA inoculated Golden Montazah eggs was higher [78.1%] than the Gimmizah treated eggs and the controls. Although, the Gimmizah DNA injected breed showed the highest hatchability rate [60.9%], since their chicks [at 40 mug DNA level] had the lowest hatch weight [20.8 g]. On the contrary, the Golden Montazah [at 40 mug DNA level] had the highest body weight [P <0.05] by the 4th-8th week of age. A significant gradual increase in humoral immune response to NDA vaccination up to the 8th week of age was observed in all the DNA injected groups of the Golden Montazah chickens. The vaccinated DNA injected groups maintained high levels of virus neutralizing antibodies being produced by IBD vaccination in the 2 breeds over the control groups. Although, the level of antibodies against IBDV was low in the nonvaccinated IBDV injected groups, they resisted the challenge with the IBDV at 48 days of age. Protection percentage in nonvaccinated group was 35% in Golden Montazah and 10% in Gimmizah breeds. Bursal atrophy value was >0.7 [in all treated groups], which indicated no clear bursal atrophy. Bursal cells of transgenic Golden Montazah chickens have the highest nuclear DNA content than all other groups before and after challenge. Meanwhile, IBD vaccinated DNA injected groups had lower bursal lesions [index] indicating more substantial protection [immunity] against challenge. In conclusion, hyperimmune transgenic chickens can be produced by quail bursal DNA inoculation

Allergic rhinitis with and without nasal polypi [Electron microscopic study]

Allergic nasal polyposis is an agonizing problem in the practice of otorhinolaryngology. The exact etiology and pathogenesis are still a matter of controversy. The present work aimed to clarify the sequence of events in the pathogenesis of nasal allergy and to throw a light on the initiating factors that predispose to polypoidal formation. Nasal biopsies were taken from selected twenty male patients with allergic rhinitis [10 patients without polypi and 10 with polypi]. The associated polypus tissue was studied. Biopsies were taken also from five volunteers used as a control. Electron microscopic study of the allergic nasal mucosa showed thickening and metaplasia of the lining epithelium with thickening of their basement membrane. The lamina propria manifested cellular infiltration especially those of fibroblast, lymphocytes, plasma cells, macrophages and mast cells which depicted a degree of degranulation more in cases with polyposis. The glandular structures showed hyperactivity of the serous element with loss of their microvilli and cilia. Zymogen granules appeared more numerous and of more electron density. There was increased vasculature with hypertrophy and gaping of the endothelial lining cells and thickening of the basal lamina of blood capillaries. Polypus tissue showed a structure similar to that of allergic nasal mucosa. Their epithelial cells were widely separated and the stroma was edematous. The vasculature and glandular elements were greatly reduced. The ultrastructural changes in allergic rhinitis with elements were greatly reduced. The ultrastructural changes in allergic rhinitis with and without polyposis were more or less the same. The changes were more marked in cases with polyposis. This might be due to difference in the degree of tissue reaction to allergen which may be due to the variability in the initial site that provoke it

Study of the effect of high dietary iodine on blood of broiler chickens

The aim of this study was to elucidate the effect of high dietary iodine on some biochemical and hematological parameters of broiler chickens. The obtained data showed that the thyroidal hormones concentration [T3 and T4], alkaline phosphatase activity [ALP], aspartate aminotransferase activity [ASAT] and urea level were significantly increased in the sera of chickens kept on high dietary iodine [150 ppm in drinking water] at the 3rd and the 6th weeks post treatment. On the other h and, calcium, iron and creatinine levels were significantly increased [P <0.05] at the 6th week only. Concerning the blood picture, the obtained results revealed that, the red blood cells [RBCs] count, lymphocytic percentage, hemoglobin [Hb] concentration and packed cell volume [PCV] values were significantly increased in the iodine supplemented chickens, while the white blood cells [WBCs] count and heterophil percentage were significantly decreased in the same group

In vitro and in vivo comparative studies on the efficacy of some aflatoxin-detoxifying agents

In vitro comparative efficacy studies on the addition of 3 different levels of each of aluminum oxide, antitox plus, charcoal, fix-a-tox and florisil as detoxifying agents to sorghum containing 46 ppm aflatoxin were carried out. The 0.1% level gave the most constant pattern with aflatoxin reductions of 42.8, 61.6, 36.9, 27.2 and 25.2% for the above agents, respectively. Raising the level to 0.5% of each agent resulted in reduction of 0.0, 77.8, 44.1, 1.8 and 40.5%. The highest tested level [1%] gave only reduction of 41.3, 30.2, 32.0, 18.2 and 18.3%

Omega-3 polyunsaturated fatty acids in relation to fish feeding habit

A correlation was found between the fatty acids composition of feed and lipid metabolism of the fish. The proportion of total n-6 PUFA was higher, while the total n-3 PUFA and the n-3/ n-6 were significantly lower in omnivorous fish as compared with carnivorous and herbivorous fish. The percentages of n-3 PUFA and especially 22:6 n-3 and 20:5 n-3 were higher in the herbivorous fish, while carnivorous fish exhibited the highest level of saturated fatty acids

effect of high dietary potassium iodide on serum lipids, lipoprotein patterns and body weight gain of cockerels

A total of thirty Fayoumi cockerels [12 weeks] were used in this experiment. The birds were divided into two equal groups. One of them was supplemented by high dietary potassium iodide. The other group was used as control. Blood was collected after 3rd and 6th weeks. Total serum lipids, total cholesterol, high density lipoprotein [HDL], low density lipoprotein [LDL] showed a significant reduction at 3rd and 6th weeks while triacylglycerol and very low density lipoprotein [VLDL] were significantly decreased at 6th weeks. No significant differences were detected between the phospholipids content of the serum of supplemented and control groups

Effect of dietary cholesterol and olive oil on serum lipids and yolk cholesterol of laying hens

Effect of dietary cholesterol and olive oil on serum lipids and egg yolk cholesterol were investigated. Thirty Hisex brown hens at 25 weeks of age were used in two trials by feeding two basal diets containing 1% cholesterol with or without 10% olive oil. The feeding of cholesterol alone resulted in a significant decrease in serum phospholipids, while cholesterol-olive diet increased its level. In contrast. feeding of cholesterol alone caused an increase in the serum levels of triacylglycerol, total lipids and cholesterol. The previous results were adversed by adding olive oil to cholesterol in the diet. Although, adding of olive oil to diet containing cholesterol leads to a decease in the serum cholesterol level, yet it fails to make the same effect in the egg yolk cholesterol content