[Endoscopically non-removable stones of the common bile duct]. / Endoskopicheski ne udalimye kamni obshchego zhelchnogo protoka: puti resheniya problemy.

OBJECTIVE: To evaluate the effectiveness of long-term biliary stenting in the treatment of endoscopically intractable common bile duct stones. MATERIAL AND METHODS: The study enrolled 247 patients with endoscopically non-removable bile duct calculi («difficult¼ choledocholithiasis) divided into two comparable groups. The main group included 129 patients who underwent biliary stenting with original stents with a nanocarbon inert coating (RF patent No. 84226), including those with inclusion of silver nanoclusters (RF patent No. 129397). The control group included 118 patients who underwent all methods of surgical treatment of choledocholithiasis, while biliary stents with original nanocarbon silver-containing inert coating were excluded. The vast majority of patients were women of advanced age (mean 66.8±4.7 and 66.3±5.6, max 89 and 90, min 32 and 37 years, respectively). RESULTS: In the control group, all patients underwent endoscopic transpapillary interventions as soon as possible. We could not extract common bile duct stones via endoscopic approach in 56.8% of cases. These patients underwent open or laparoscopic choledocholithotomy with lithoextraction. Complications occurred in 28.5% of cases. Mortality rate was 4.2%. Standard stenting of common bile duct was performed in 28.8% of cases. At the same time, stent dysfunction followed by relapse of obstructive jaundice occurred in 27.1% of patients within 3-3.5 months. Of these, 16 patients (13.5%) underwent stent removal and lithoextraction. Re-stenting was performed in 18 patients (15.3%). Moreover, shock wave lithotripsy with subsequent removal of common bile duct calculi was performed in 8 (6.8%) of these patients the next day. In the main group, original biliary plastic stents with nanocarbon silver-containing inert coating were implanted in all patients. Under permanent therapy with ursodeoxycholic acid drugs, we observed significant shrinkage of calculi to 11.8±1.8 mm and decrease in their density. This made it possible to carry out successful extraction of calculi in 81 patients (62.8%) after 6±0.3 months. Shock wave lithotripsy was performed in 36 (27.9%) cases. This procedure was successful and allowed final lithoextraction in 28 patients (21.7%). Re-stenting was performed in 15 (11.6%) cases, laparotomy - in 5 (3.9%) patients. Mortality rate was 0.78%. CONCLUSION: Our data allow us to discuss high efficiency of long-term bile duct stenting with plastic stents with nanocarbon silver-containing inert coating in complex treatment of choledocholithiasis. This approach ensures acceptable incidence of undesirable complications and mortality. This situation undoubtedly dictates the need for further larger prospective studies.

Use of urinary renal biomarkers to evaluate the nephrotoxic effects of melamine or cyanuric acid in non-pregnant and pregnant rats.

Although traditional assessments of renal damage detect loss of kidney function, urinary renal biomarkers are proposed to indicate early changes in renal integrity. The recent adulteration of infant formula and other milk-based foods with melamine revealed a link between melamine ingestion and nephropathy. Thus, the effects of melamine and related analogs (e.g., cyanuric acid) should be assessed in other potentially sensitive groups. We evaluated whether urinary Kim-1, clusterin, and osteopontin could detect the effects of high doses of melamine or cyanuric acid in pregnant and non-pregnant female rats gavaged with 1000 mg/kg bw/day for 10 days. We demonstrate that these biomarkers can differentiate the severity of effects induced by melamine or cyanuric acid. All melamine-treated animals experienced adverse effects; however, pregnant rats were most sensitive as indicated by increased SCr, BUN, and kidney weights, decreased body weight, and presence of renal crystals. These effects coincided with elevated urinary biomarker levels as early as day 2 of exposure. One cyanuric acid-treated rat displayed effects similar to melamine, including increased urinary biomarker levels. This work illustrates that these biomarkers can detect early effects of melamine or cyanuric acid crystal-induced nephropathy and further supports the use of urinary protein immunoassays as a powerful, non-invasive method to assess nephrotoxicity.

Acute toxicity of sodium arsenite in a complex food matrix.

Acute toxicity of a single oral dose of sodium arsenite (As), administered in half and half cream (HH), was assessed in male and non-pregnant female rats (0.41, 4.1, 41.0 and 410.0mg/kg body weight) and pregnant rats (0.41, 4.1 and 41.0mg/kg body weight). Control rats received deionized water alone, HH alone or 41.0mg/kg As in deionized water (41 mg/kg As-water). Male and non-pregnant rats were monitored for 14 consecutive days post-dosing. Pregnant rats, dosed on gestation day 10 (GD-10), were monitored until fetuses were collected on GD 20. High mortality (100%) was observed in male and non-pregnant female rats exposed to 410.0mg/kg As-HH. Low mortality (25%) was observed in non-pregnant female rats exposed to 41 mg/kg As-water. No mortality was observed in other control or treated groups. Reduced female fetal numbers were observed in the 41 mg/kg As-water group but not in the other control groups. Developmental effects were not observed in the controls or the As-HH treatment groups. In conclusion, As toxicity was not reduced when a high dose (410 mg/kg) was administered in HH however, at lower doses (41 mg/kg), HH reduced acute As oral toxicity in the female and developing fetus.

Flaxseed increased alpha-linolenic and eicosapentaenoic acid and decreased arachidonic acid in serum and tissues of rat dams and offspring.

The effects of dietary flaxseed (FS), and defatted flaxseed meal (FLM) on serum and tissue fatty acid profiles were investigated. Pregnant Sprague-Dawley rats were fed AIN-93 based diets balanced in calories, fat, nitrogen, and fiber. Diets contained 0, 20%, 40% FS or 13% or 26% FLM by weight. The control, FS and FLM diets differed in linoleic acid to alpha-linolenic acid (ALA) fatty acid ratio. These diets were fed continuously during gestation, suckling period and 8 weeks post-weaning (F(1)). FS fatty acids were bioavailable and metabolized by pregnant and F(1) rats. ALA and eicosapentaenoic acid increased; linoleic and arachidonic acid decreased; and docosahexaeonic acid was unchanged in serum, 'gastric milk' and liver of FS and FLM-fed pregnant and F(1) rats. FS more than FLM, changed fatty acids profiles, but FLM and 40% FS significantly reduced serum cholesterol. Dietary 40% FS may have increased oxidative stress as evidenced by a reduction in liver vitamin E.

Impact of high flaxseed diet on mitogen-induced proliferation, IL-2 production, cell subsets and fatty acid composition of spleen cells from pregnant and F1 generation Sprague-Dawley rats.

Flaxseed (FS) being rich in alpha-linolenic acid may alter the immune parameters. Therefore, we assessed the impact of FS and defatted flaxseed meal (FLM) on fatty acid composition, cell subsets, proliferation and IL-2 production by splenic lymphocytes. Pregnant female Sprague-Dawley rats were fed diets containing 0% FS and FLM, 20 or 40% FS, 13 or 26% FLM during gestation or gestation, lactation and 8 week post-weaning period. FS and FLM resulted in up to 8.3 fold and 4.6 fold increase in splenic ALA among pregnant rats, 4.5 fold and 1.2 fold increase in splenic ALA among F(1) generation rats. Splenic linoleic acid (LA) and arachidonic acid (AA) were 18 and 40% lower in 40% FS fed pregnant rats, and AA was 15% lower in all the other groups. Among F(1) rats, splenic LA and AA were 16 and 48% lower in 40% FS group, and AA was 18% lower in 20% FS and 26% FLM groups. Concanavalin A and phytohemagglutinin mediated proliferation of spleen cells were 60 and 52% lower in 40% FS fed pregnant and F(1) generation rats, respectively. No significant changes were observed in the cell subsets or IL-2 production by splenic cells from different groups.

Developmental toxicity of sodium fluoride measured during multiple generations.

Sodium fluoride (NaF) has been used to fluoridate drinking water in the United States since the mid 1940s. Because of the lack of reliable studies on the multigeneration effects of the compound, NaF (0, 25, 100, 175 or 250 ppm in drinking water) was given to rats continuously during three generations. Parental (F0) generation rats were treated for 10 weeks and mated within groups. At gestation day 20, caesarean sections were performed and eight F0 females per group and their litters (F1) were observed for implant status, fetal weight and length, sex and morphological development. The remaining F0 females (29-32 per group) were allowed to litter. F1 offspring (36 of each sex per group) were mated within groups, and caesarean sections were performed at gestation day 20. The F1 females and their litters (F2) were observed for implant status, fetal weight and length, sex and morphological development. In addition, F2 fetuses were evaluated for internal (soft-tissue) and skeletal development. Decreased fluid consumption for F0 and F1 dams at 175 and 250 ppm was attributed to decreased palatability of the solution. No dose-related effects in feed consumption or mean body weight gain were observed in either F0 or F1 females. Numbers of corpora lutea, implants, viable fetuses and fetal morphological development were similar in all groups. No dose-related anomalies in internal organs were observed in F2 fetuses. Ossification of the hyoid bone of F2 fetuses was significantly decreased at 250 ppm. Because of the decreased ossification of the hyoid bone, 250 ppm is considered the effect level.

Multigenerational evaluation of sodium fluoride in rats.

Since the mid 1940s, fluoride has been added to tap water in American communities in an effort to reduce the incidence of dental caries in the population. When the levels of fluoride in drinking water were tested and set, water was the only measurable source of fluoride for most communities. Now, adults and children ingest fluoride with foods and beverages prepared with fluoridated water, and they are exposed to fluoride-containing dental products. As a result, exposure to fluoride is greater than had been anticipated. In the early 1990s, the existing reproductive studies were reviewed in several reports and were considered to be inadequate to determine potential reproductive or developmental hazards. The effects of sodium fluoride ingestion at 0, 25, 100, 175 or 250 ppm in drinking water measured in rats throughout three generations are reported here. Feed and fluid consumption, body weights and clinical signs were recorded at regular intervals. Decreased fluid consumption observed at 175 and 250 ppm was attributed to decreased palatability and did not affect reproduction. No cumulative effects were observed in the three generations. Mating, fertility and survival indices were not affected. Organ-to-body-weight ratios and organ-to-brain weight ratios were not affected. Sodium fluoride up to 250 ppm did not affect reproduction in rats.

Testing the potential of flaxseed to affect spermatogenesis: morphometry.

Quantitative information was collected on male reproductive effects of maternal and postnatal dietary exposure to flaxseed (20 or 40%), flaxmeal (13 or 26%) or standard NIH AIN-93 feed (0% flaxseed control). Measurements were made on the testes of F1 generation males rats (1) whose mothers were exposed to the diets designated above, and (2) who, after weaning, were placed on the same diet as their mothers for an additional 70 days. The seminiferous tubules comprised 86%, 84%, 84%, 84% and 85% of the total testis volume while the interstitial space comprised 12%, 14%, 14%, 14%, 13% of the total testis volume for the 0% flaxseed/flaxmeal, 20% flaxseed, 13% flaxmeal, 40% flaxseed and 26% flaxmeal groups, respectively. Statistically significant decreases in the absolute volume of the seminiferous tubules were observed in the 20% and 40% flaxseed-treated groups when these groups were compared to controls. Borderline statistically significant differences were also observed when Sertoli cell nucleolar number per tubular cross-section were compared in the 13% flaxmeal and 20% flaxseed treatment groups. These effects were not considered biologically significant because other parameters of male reproductive function appeared normal. Overall, the quantitative information obtained suggests that exposure to flaxseed/flaxmeal at the doses used in the present study does not adversely affect testis structure or spermatogenesis in the rat.

Automated high throughput human CYP isoform activity assay using SPE-LC/MS method: application in CYP inhibition evaluation.

1. A high throughput screening (HTS) method for the evaluation of the seven major human hepatic CYP isoform activities was developed on a 96-well format, with automation. The method utilized pooled human liver microsomes and seven probe substrates, generic conditions for incubation, reaction termination and metabolite extraction with solid phase extraction (SPE) plates. Metabolites from the seven reactions were pooled and quantified using a generic liquid chromatography and tandem mass spectrometry (LCMS/MS) method. 2. The HTS method was validated based on Km values obtained, which were in agreement with literature data. 3. The isoform inhibition profiles of ketoconazole, quinidine, sulfaphenazole, tranylcypromine, alpha-naphthoflavone, and 4-methylpyrazole against CYPs 3A4, 2D6, 2C9, 2A6 land 2C19), 1A2 and 2E1, respectively, were obtained by this HTS method. Graphically obtained IC50 values are in agreement with literature reported values. 4. The HTS method represents a significant efficiency and selectivity improvement over traditional methods, and can be used for CYP inhibition assay and can be extended for liver activity profiling.

The effect of maternal exposure to flaxseed on spermatogenesis in F(1) generation rats.

Pregnant Sprague-Dawley rats were exposed to a flaxseed (20 or 40%), flaxmeal (13 or 26%) or standard NIH AIN-93 (0% flaxseed control) diet throughout gestation and until their offspring were weaned. After weaning, F(1) generation males were placed in the same diet treatment groups as their mothers for 70 days. Statistically significant differences were not observed between either low-dose or high-dose flaxseed and flaxmeal-treated animals and the 0% flaxseed control animals for testis weights, homogenization resistant spermatid counts, daily sperm production rates, epididymal weights, seminal vesicle weights, seminiferous tubule fluid testosterone concentrations and the percentage of sperm abnormalities. The following statistically significant differences were observed when treated groups and the 0% flaxseed control groups were compared: (1) increases in serum LH in the 20% and 40% flaxseed treatment groups and in serum LH and testosterone in the 26% flaxmeal treatment group; (2) increases in the cauda epididymal weight from the 20% and 40% flaxseed groups; (3) increases in cauda epididymal sperm numbers/g epididymis from the 20% and 40% flaxseed and the 13% and 26% flaxmeal treatment groups; (4) a decrease in prostatic weight from the 20% flaxseed and 13% and 26% flaxmeal treatment groups. Prostate weight in the 40% flaxseed treatment group was lower but not statistically significantly different than the 0% flaxseed control group. Histological effects on spermatogenesis were not observed in either the control group, flaxmeal or the flaxseed treated groups.

Light microscopic observations on the reproductive tract of the male sand rat, Psammomys obesus.

The anatomy of the reproductive tract of the male sand rat, Psammomys obesus, was examined by light microscopy. Histologically, the reproductive tract is similar to other rodent species. Seminiferous tubules in the 1-month-old sand rat do not contain a tubular lumen but Sertoli cells, spermatogonia and spermatocytes are present. A full complement of germ cells is present in the seminiferous tubules by 2.5 months and spermatogenesis is well established. The interstitial space is not well defined until 2.5 months when cell types typical of most rodent species are observed. The epididymis is not noticeably segmented into lobules. An epididymal lumen is not observed until 2.5 months. Cauda epididymal sperm are not observed in the 1 or 2.5-month-old animals and cauda epididymal sperm counts from the 7.5 and 12.5-month-old animals are highly variable. The epididymis, proximal and middle regions of the vas deferens, seminal vesicles and prostate display morphological and histological characteristics similar to other rodent species. The distal end of the vas deferens is not expanded to form an ampulla.

Testing the potential of sodium fluoride to affect spermatogenesis: a morphometric study.

This study provides quantitative information on the effect of sodium fluoride (NaF) on the testes of F1 generation male rats exposed in utero and during lactation to NaF at one of four concentrations (25, 100, 175, 250 ppm). At weaning, the F1 generation males were exposed to NaF in their drinking water for 14 weeks, after which time testicular tissues were perfusion-fixed with glutaraldehyde and observed after being embedded in plastic. The seminiferous tubules comprised 89%, 87%, 88%, 88% and 88% of the total testis volume while the interstitial space occupied 9.3%, 11.2%, 10.2%, 9.8% and 9.9% of the total testis volume for the 0, 25, 100, 175 and 250 ppm NaF treatment groups, respectively. Statistically significant differences between control and NaF-treated rats were not observed with respect to absolute volume of the seminiferous tubules, interstitial space, Leydig cells, blood vessels boundary layer, lymphatic space, macrophages, tubular lumen or absolute tubular length and absolute tubular surface area, mean Sertoli cell nucleoli number per tubular cross-section, mean seminiferous tubule diameter and the mean height of the seminiferous epithelium. A statistically significant decrease in the absolute volume and volume percent of the lymphatic endothelium was observed in the 175 and 250 ppm NaF-treated groups and in the testicular capsule in the 100 ppm NaF-treated groups. The significance of this finding is unknown at the present time. Overall, the quantitative information obtained suggests that exposure to NaF at the doses used in the present study does not adversely affect testis structure or spermatogenesis in the rat.

Effects of fumonisin B1 in pregnant rats. Part 2.

The developmental toxicity of purified fumonisin B1 (FB1), a mycotoxin from the common corn fungus Fusarium moniliforme, was examined in Charles River rats. Pregnant rats were dosed orally on gestation days 3-16 at 0, 6.25, 12.5, 25 or 50 mg FB1/kg body weight/day. FB1 was not teratogenic at the doses tested. At 50 mg/kg, maternal toxicity (inappetence, emaciation, lethargy, death, resorption of entire litters) and foetal toxicity (increased number of late deaths, decreased foetal body weight, decreased crown rump length, increased incidence of hydrocephalus, increased incidence of skeletal anomalies) were seen. The foetal toxicity observed at 50 mg/kg may be related to maternal toxicity. Histopathological evaluation of tissues from dams of control and all treated groups revealed dose-related toxic changes in kidney and liver tissues. Acute toxic tubular nephrosis was seen in kidneys from all treated groups. Hepatocellular cytoplasmic alteration and individual cellular necrosis of the liver was seen in the two high-dose groups. Sphinganine (Sa) and sphingosine (So) were measured in day-17 adult and foetal tissues. Dose related increases in Sa/So ratios were seen in maternal liver, kidney, serum and brain, but there was no effect on foetal liver, kidney and brain. These data suggest that FB1 does not cross the placenta and further suggest that the observed foetal toxicity is a secondary response to maternal toxicity.

Effects of fumonisin B1 in pregnant rats.

Fumonisin B1 (FB1), the major mycotoxin from Fusarium moniliforme, has been implicated as a causative agent in several animal and human diseases. Despite animal toxicity studies and human epidemiological studies of FB1, knowledge of its reproductive effects is scarce. In this study, one of a series of proposed studies that will allow extrapolation to humans, pregnant rats were given oral doses of 0, 1.875, 3.75, 7.5 or 15 mg FB1/kg on gestation days 3 16. Caesarean sections were performed on day 17 or 20, and maternal condition, implantation efficiency, foetal viability and foetal development were measured. Dose-related decreases in overall feed consumption and body weight gain were seen, but only the feed consumption decrease at 15 mg/kg, and the decreased body weight gain at 15 mg/kg on days 0-17 were statistically significant. Foetal body weights at day 17 were similar in control and treated groups; but in day-20 foetuses, female weight and crown-rump length were significantly decreased at 15 mg/kg. FB1 was not teratogenic at the doses tested, and no dose-related effects were seen in either skeletal or soft-tissue development. In day-17 animals, maternal and foetal brain, liver and kidney tissues, and maternal serum were preserved to study the levels of sphinganine (Sa), sphingosine (So), and the Sa/So ratios. Dose-related increases were seen in Sa/So ratios in maternal livers, kidneys and serum. Sa/So ratios of maternal brains were not affected, nor were those of foetal kidneys, livers or brains.

Developmental toxicity of sodium fluoride in rats.

Despite the chronic exposure of the US population to fluoridated drinking water since the 1940s, existing studies have been judged inadequate to determine any potential reproductive or developmental hazard. This study was conducted to determine the effects of sodium fluoride (NaF) on foetal development. Sperm-positive female rats were given 0, 10, 25, 100, 175 or 250 ppm NaF daily throughout gestation. They were dosed by drinking water to mimic human exposure to fluoridated water. No dose-related behavioural changes or maternal clinical signs were noted. Fluid consumption by females in the 175- and 250-ppm groups was significantly less than that of the control females. Because of this decreased fluid consumption, the daily amount of NaF ingested (0, 1.4, 3.9, 15.6, 24.7 and 25.1 mg/kg body weight) was less than expected at the two high levels. Feed consumption decreased significantly at 250 ppm, and body weights of pregnant females reflected feed consumption trends. The mean number of viable foetuses per female in all treated groups was similar to that of the control group. The significant decrease in the mean number of implants per litter in the 250-ppm group is probably linked to the lower mean number of corpora lutea in this group. The occurrence of in utero deaths was similar in the control and treated groups. Foetal growth (in terms of foetal body weight and crown-rump length) was not affected by NaF, despite the fact that the dams in the 250-ppm group ate significantly less feed and drank significantly less fluid. There was no dose-related increase in the number of external anomalies in foetuses due to NaF ingestion. At the doses given, NaF had no effect on the development of specific bones, including sternebrae. A significant increase was seen in the average number of foetuses with three or more skeletal variations in the 250-ppm group; the number of litters with foetuses with three or more skeletal variations was increased in the 250-ppm group also, but the increase was not significant. There was no dose-related effect of NaF on the incidence of soft tissue variations.