Industrial, Biocide, and Cosmetic Chemical Inducers of Cholestasis.

A frequent side effect of many drugs includes the occurrence of cholestatic liver toxicity. Over the past couple of decades, drug-induced cholestasis has gained considerable attention, resulting in a plethora of data regarding its prevalence and mechanistic basis. Likewise, several food additives and dietary supplements have been reported to cause cholestatic liver insults in the past few years. The induction of cholestatic hepatotoxicity by other types of chemicals, in particular synthetic compounds, such as industrial chemicals, biocides, and cosmetic ingredients, has been much less documented. Such information can be found in occasional clinical case reports of accidental intake or suicide attempts as well as in basic and translational study reports on mechanisms or testing of new therapeutics in cholestatic animal models. This paper focuses on such nonpharmaceutical and nondietary synthetic chemical inducers of cholestatic liver injury, in particular alpha-naphthylisocyanate, 3,5-diethoxycarbonyl-1,4-dihydrocollidine, methylenedianiline, paraquat, tartrazine, triclosan, 2-octynoic acid, and 2-nonynoic acid. Most of these cholestatic compounds act by similar mechanisms. This could open perspectives for the prediction of cholestatic potential of chemicals.

[Study on Risk Assessment Model of in Vitro Diagnostic Reagent Adverse Events Based on BP Neural Network].

OBJECTIVE: To modify the monitoring process and means of adverse events in vitro diagnostic reagents,improve the quantity and quality of adverse events reported in vitro,and reduce the workload of regulatory authorities,eventually ensure the safety and effectiveness of in vitro diagnostic reagents. METHODS: The pre-filtering risk assessment system based on BP neural network was used to evaluate the adverse events of in vitro diagnostic reagents.According to the evaluation results,the administrative supervision departments took corresponding countermeasures. RESULTS: The BP neural network learned the historical data,and the risk evaluation results of the adverse events were basically consistent with the expert group. CONCLUSIONS: BP neural network can be used to evaluate the risk of adverse events and achieve risk signal aggregation of adverse events.

[Discussion on Regulatory Risk of in Vitro Diagnostic Reagents in Use].

According to the information of the supervision and inspection of in vitro diagnostic reagents for clinical use, this article analyzed the compliance issues and discussed the methods to solve the problems, to urge medical institutions to reduce the regulatory risk of in vitro diagnostic reagents in use.

[Acute generalized exanthematous pustulosis induced by phloroglucinol]. / Pustulose exanthématique aiguë généralisée induite par le phloroglucinol (Spasfon®).

BACKGROUND: Acute generalized exanthematous pustulosis (AGEP) is a severe drug eruption. We report herein the first case of AGEP induced by phloroglucinol (Spasfon®). PATIENTS AND METHODS: A 27-year-old pregnant woman developed a febrile exanthematous pustulosis eruption three days after treatment with intravenous phloroglucinol and paracetamol for nephritic colic. She had no previous history of psoriasis. The laboratory workup showed hyperleukocytosis with neutrophilia. A cytobacteriological sample of the pustules was negative. Skin biopsy revealed marked neutrophilic and leukocytoclastic vasculitis. Reintroduction of phloroglucinol after delivery resulted in the same clinical symptoms within a few hours of intake. A diagnosis of phloroglucinol-induced AGEP was made on the basis of intrinsic imputability of I4 (S3 C3) using the imputability criteria of Begaud et al. The outcome was favorable after withdrawal of the drug. DISCUSSION: To the best of our knowledge, this is the first case of phloroglucinol-induced AGEP confirmed by reintroduction of the drug.

Motility and chemotaxis mediate the preferential colonization of gastric injury sites by Helicobacter pylori.

Helicobacter pylori (H. pylori) is a pathogen contributing to peptic inflammation, ulceration, and cancer. A crucial step in the pathogenic sequence is when the bacterium first interacts with gastric tissue, an event that is poorly understood in vivo. We have shown that the luminal space adjacent to gastric epithelial damage is a microenvironment, and we hypothesized that this microenvironment might enhance H. pylori colonization. Inoculation with 106 H. pylori (wild-type Sydney Strain 1, SS1) significantly delayed healing of acetic-acid induced ulcers at Day 1, 7 and 30 post-inoculation, and wild-type SS1 preferentially colonized the ulcerated area compared to uninjured gastric tissue in the same animal at all time points. Gastric resident Lactobacillus spp. did not preferentially colonize ulcerated tissue. To determine whether bacterial motility and chemotaxis are important to ulcer healing and colonization, we analyzed isogenic H. pylori mutants defective in motility (ΔmotB) or chemotaxis (ΔcheY). ΔmotB (10(6)) failed to colonize ulcerated or healthy stomach tissue. ΔcheY (10(6)) colonized both tissues, but without preferential colonization of ulcerated tissue. However, ΔcheY did modestly delay ulcer healing, suggesting that chemotaxis is not required for this process. We used two-photon microscopy to induce microscopic epithelial lesions in vivo, and evaluated accumulation of fluorescently labeled H. pylori at gastric damage sites in the time frame of minutes instead of days. By 5 min after inducing damage, H. pylori SS1 preferentially accumulated at the site of damage and inhibited gastric epithelial restitution. H. pylori ΔcheY modestly accumulated at the gastric surface and inhibited restitution, but did not preferentially accumulate at the injury site. H. pylori ΔmotB neither accumulated at the surface nor inhibited restitution. We conclude that bacterial chemosensing and motility rapidly promote H. pylori colonization of injury sites, and thereby biases the injured tissue towards sustained gastric damage.

Contrast-Induced Acute Kidney Injury: Comparison of Preventative Therapies.

Contrast medium is used daily for diagnostic and interventional procdures as a means to visualize blood vessels. The administration of contrast dye, however, can lead to an acute reduction in kidney function. This complication can impact length of hospital stay, risk of dialysis, and increased hospital mortality. Common preventative measures include N-acetylcysteine and intravenous hydration. The evidence reviewed revealed hydration to be the more effective treatment to reduce the risk of acute kidney injury.

Osmolyte effects on the self-association of concanavalin A: testing theoretical models.

The formation and stability of protein-protein interfaces are of obvious biological importance. While a large body of literature exists describing the effect of osmolytes on protein folding, very few studies address the effect of osmolytes on protein association and binding. The plant lectin concanavalin A (ConA), which undergoes a reversible tetramer-to-dimer equilibrium as a function of pH, was used as a model system to investigate the influence of nine osmolytes on protein self-association. The stabilizing or destabilizing impacts of the osmolytes were evaluated from pH titrations combined with circular dichroism spectroscopy. Relative to the dimer, trimethylamine N-oxide, betaine, proline, sarcosine, sorbitol, sucrose, and trehalose all stabilized the ConA tetramer to varying extents. Glycerol had a negligible effect, and urea destabilized the tetramer. From multiple titrations in different osmolyte concentrations, an m-value (a thermodynamic parameter describing the change in the association free energy per molar of osmolyte) was determined for each osmolyte. Experimental m-values were compared with those calculated using two theoretical models. The Tanford transfer model, with transfer free energies determined by Bolen and co-workers, failed to accurately predict the m-values in most cases. A model developed by Record and co-workers, currently applicable only to urea, betaine, and proline, more accurately predicted our experimental m-values, but significant discrepancies remained. Further theoretical work is needed to develop a thermodynamic model to predict the effect of osmolytes on protein-protein interfaces, and further experimental work is needed to determine if there is a general stabilization by osmolytes of such interfaces.

Notes from the field: Multistate outbreak of postprocedural fungal endophthalmitis associated with a single compounding pharmacy - United States, March-April 2012.

On March 5, 2012, the California Department of Public Health was notified of nine cases of clinically diagnosed fungal endophthalmitis at a single California ambulatory surgical center. The initial investigation, led by the Los Angeles County Department of Public Health, determined that in all cases patients had undergone vitrectomy with epiretinal membrane peeling using a dye called Brilliant Blue-G (BBG) from Franck's Compounding Lab, Ocala, Florida. This investigation has since expanded to involve intravitreal injection of triamcinolone-containing products from Franck's, an overall total of 33 cases in seven states, and collaboration between state and local health departments, CDC, and the Food and Drug Administration (FDA). This report describes the current investigative findings. Clinicians should be aware of the ongoing investigation and should avoid use of compounded products labeled as sterile from Franck's during this ongoing investigation.

[Analysis of Flame Retardants Bis(2,3-dibromopropyl) phosphate and Tris(2,3-dibromopropyl) phosphate in Textile Products by GC-MS].

The use of flame retardants, namely bis(2,3-dibromopropyl) phosphate (BDBPP) and tris(2,3-dibromopropyl) phosphate (TDBPP), in textile products such as curtains, carpets and sleeping clothes is banned in Japan under the 'Act on the Control of Household Products Containing Harmful Substances'. Herein, we developed a GC-MS based method to quantify these compounds with greater accuracy and safety than the current official method. For accurate and sensitive quantification, deuterated compounds, BDBPP-d10 and TDBPP-d15, were used as surrogate standards. In consideration of the safety of the analyst, certain solvents and reagents used for the pretreatment that are carcinogenic or have a risk of explosion were replaced. For the extraction step, benzene was replaced by ethyl acetate, and for the methyl derivatization step, the reagent was changed from a self-prepared solution of diazomethane in ether to a solution of trimethylsilyl diazomethane in hexane, a safe and easy-to-use commercially available reagent. The calibration curves were liner in the range of 0.5-8.0 µg/mL for both methylated BDBPP (BDBPP-Me) and TDBPP. The detection limit was 0.05 µg/g for BDBPP-Me and 0.3 µg/g for TDBPP, which is sufficiently low compared to the current detection limits of 10 µg/g for BDBPP-Me and 8 µg/g for TDBPP. The recoveries in various curtain material were 66-108% and relative standard deviations were 1.2-10.2% when 5 µg BDBPP and TDBPP were added to 0.5 g of samples. Thus, the developed method is applicable to textile products of various materials.

Colloid centrifugation removes seminal plasma and cholesterol from boar spermatozoa.

The objective of the present study was to investigate the effect of Single-Layer Centrifugation (SLC) on boar spermatozoa, namely the effect of removal of seminal plasma proteins and cholesterol from the surface of spermatozoa. The presence of porcine seminal plasma proteins I and II (PSP-I/PSP-II) before and after SLC was studied using immunofluorescence, whereas the removal of cholesterol was shown qualitatively by thin-layer chromatography (TLC). Finally, the integrity of the sperm plasma membrane was observed by electron microscopy. It was shown that the seminal plasma proteins PSP-I and -II were removed from spermatozoa during SLC but could be restored by adding seminal plasma to the SLC-selected sperm samples. Some cholesterol was also lost from the spermatozoa during SLC but the plasma membrane itself appeared to be morphologically intact. Further studies are underway to examine the relevance of these findings to boar sperm cryopreservation and sperm fertility.

[Stressful effects of chemical toxins at low concentrations].

Effects of three chemical compounds: ammonia, diethyl ether, and acetic acid, known as common environmental contaminants in technogenic accidents, were investigated in vivo and in vitro in low concentrations. When added in cultivation media, each of the chemicals has affected peritoneal macrophages and spleen lymphocytes isolated from male NMRI mice and led to a rise in the production of several cytokines, particularly the tumor necrosis factor-alpha and interferon-gamma, as well as the expression of the inducible form of heat shock proteins (HSP72 and HSP90-alpha) and in the activation of signal cascades NF-kappaB and SAPK/JNK. The increase of the nitric oxide (NO) production in macrophages has been observed only when ammonia was added in cultivation media. Also, low concentrations of all compounds investigated led to the activation of the expression of receptor protein TLR4. When mice were exposed to airborne toxic contaminants in a hermetically sealed experimental chamber, an increase in the concentrations of cytokines, heat shock proteins, and signal proteins in immune cells was also observed in response to low concentrations of all chemicals investigated. Similarly to in vitro experiments, the NO production was augmented only in the presence of the airborne ammonia. The results indicate the environmental hazard of chemical contaminants even in rather low concentrations, which nevertheless lead to the stress response.

[Influence of honey, royal jelly and propolis on accelerating acetate healing of experimental gastric ulcers in rats].

This study examines gastric acetic ulcer healing in the rat after administration of honey, royal jelly and propolis into the stomach. Chronic gastric ulcers were induced in male Wistar rats by the application of 100% acetic acid to the serosal surface of the stomach on 60 sec. Bee-keeping products were administrated into the stomach from 2nd to 7th day after acetic ulcer induction. On 7th day animals were killed, and ulcer area was measured in mm2. In gastric juice pH and activity of pepsin were measured. The healing of acetic ulcers is accelerated with the administration of honey, royal jelly or propolis during six days. The largest healing effect was demonstrated with propolis and royal jelly, smaller one with the honey. It was revealed decrease of stomach acid secretion in the rats, which have received bee-keeping products versus the rats of control group.

Kastle-Meyer blood test reagents are deleterious to DNA.

The Kastle-Meyer (KM) test is a quick and easy chemical test for blood used in forensic analyses. Two practical variations of this test are the KM-rub (indirect) test and the more sensitive KM-direct test, the latter of which is performed by applying reagents directly to a suspected blood stain. This study found that sodium hydroxide present in the KM reagents eliminated the potential to generate a DNA profile when applied directly to small quantities of blood. A modified approach to the KM-rub test that increases its sensitivity is presented as a method to replace destructive KM-direct testing.

Necrotic Tuberculin Skin (Mantoux) Test Reaction: A Case Report and an Estimation of Frequency.

Tuberculin skin testing was performed on a 5-year-old girl in Phnom Penh, Cambodia. She had been immunized by Bacille de Calmette et Guérin. She was tested because of a palpable cervical node and a slightly elevated temperature. Within 48 h, a deep necrotic lesion appeared on the volar aspect of the left arm. The lesion was treated locally, and the child was not treated for suspected TB. To our knowledge, this is the first instance of necrosis in 11,392 people who received Tubersol doses since 1996 to date at our International Vaccination Center, for an estimated incidence of 0.18 per 1,000 (95% Poisson 0.04-0.70 per 1,000 doses used). At a follow-up consultation after 77 days, the lesion had scarred and the child showed no signs suggestive of active TB. Although latent TB infection remains the most likely diagnosis, other types of mycobacterial infection may be considered in the tropical setting and in the absence of signs suggestive of active TB.

Accidental subretinal brilliant blue G migration during internal limiting membrane peeling surgery.

IMPORTANCE: This case report describes a man who developed retinal changes in his right eye associated with brilliant blue G migration into the subretinal space during 2 years of follow-up. OBSERVATION: The patient's best-corrected visual acuity in the right eye was 20/70 before surgery, and it improved to 20/25 at 1 year after surgery. Fluorescein angiography showed staining during the late phase in the central macula at all follow-up visits after surgery. Multifocal electroretinography demonstrated normal amplitude and implicit times before surgery but decreased amplitudes and increased implicit times in at least 5 contiguous hexagons after surgery on all 3 examinations performed during the 2-year follow-up period. These functional changes were not topographically correlated with the area of fluorescein staining or with the internal limiting membrane peeled area, but were matched to the area where brilliant blue G accidentally entered the subretinal space. Microperimetry demonstrated reduced retinal threshold sensitivity, particularly in areas with decreased multifocal electroretinography amplitude. CONCLUSIONS AND RELEVANCE: Despite the visual acuity improvement observed in this case, multifocal electroretinography and microperimetry indicate that subretinal brilliant blue G might cause focal macular damage with a decrease of macular function suggestive of a toxic effect.