Elucidation of the molecular mechanism underlying the anti-inflammatory activity of an effective and safe bipyrazole-based compound.

INTRODUCTION: Since the synthesis of acetylsalicylic acid by Hoffmann in 1897, new classes of NSAIDs have been introduced; however, their side effects have limited their clinical applications. Consequently, our team has recently synthesized a novel bipyrazole compound that showed a satisfactory efficacy and safety profile. The aim of the current study was to elucidate the molecular mechanism of this bipyrazole compound. METHOD: The anti-inflammatory efficacy of the compound was assessed using formalin-induced paw edema test. Computer-assisted simulation docking experiments were carried out. Cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), tumor necrosis factor-alpha (TNFα), interleukin-1 (IL1) and interleukin-10 (IL10) gene expression were quantified with real-time polymerase chain reaction (RT-PCR) using SYBR Green technology. The samples were taken from the plantar paw of mice after formalin local injection. RESULTS: The efficacy of the bipyrazole compound was similar to that of indomethacin, diclofenac, and celecoxib, as proven by the formalin-induced paw edema. Docking study indicated a superior binding score for the studied compound relative to celecoxib, indomethacin, and diclofenac. RT-PCR assessment revealed a significant decrease in iNOS, COX-2, and TNFα gene expression in the bipyrazole-treated group. Moreover, a reduction in IL1 and nNOS gene expression levels and an increase in IL10 level were detected despite being insignificant compared to the control group. CONCLUSION: These findings revealed the superiority of the newly synthesized bipyrazole compound not only on the binding site, but also by inhibiting most of the inflammatory mediators including TNF-α.

Prevalence and characterization of extended-spectrum beta-lactamases producing Enterobacteriaceae in healthy children and associated risk factors.

BACKGROUND: Community acquired infections due to extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) had been increased. The fecal flora of children in the community represents a huge potential reservoir for ESBLs which are located on highly transmissible plasmids. This study examined the prevalence of ESBL-PE fecal carriage, antimicrobial susceptibility pattern, possible risk factors, and characterized the genes encoding these ESBL enzymes in Lebanese children community. METHODS: A total of 125 rectal swabs were taken from healthy children aged from 1 to 5 years. Detection of ESBLs was carried out using combination-disc method test and multiplex PCR. A questionnaire concerning child's lifestyle and risk factors for ESBL carriage was illustrated. RESULTS: Thirty-one of 125 participants (24.8 %) carried ESBL-PE. Regular consumption of meat, and chicken were significantly associated with high carriage rate of ESBL-PE, while dairy products (milk, yogurt, cheese) association was non-significant. Intimate hygiene habits were found also affecting the carriage rate. Multiple bla genes were the most common, 48.4 % (15/31) of ESBL-PE carried both bla CTX-M and bla TEM, and 22.6 % (7/31) carried bla CTX-M, bla SHV, and bla TEM, 29 % (9) carried bla CTX-M only. Concerning CTX-M-types, CTX-M-9 was the most predominant (24/31) and mostly in combination with CTX-M-15 type. CONCLUSION: High rate of colonization in healthy children with ESBL-PE was observed, regular consumption of dietary products from animal source (meat or chicken) were associated with this colonization in the community in non-hospitalized children. To our best knowledge it is the first study about regular consumption of dairy product as a risk factor for ESBL-PE community carriage, the first data about the carriage rate of ESBL-PE in community children in Lebanon and Middle East, and for the wide dissemination of CTX-M-9 type in this population.

Sodium ascorbate as a quorum sensing inhibitor of Pseudomonas aeruginosa.

AIMS: Quorum sensing circuits regulate virulence factors in Pseudomonas aeruginosa and coordinate bacterial pathogenicity. We are interested in exploring available medications for their antiquorum sensing activity. METHODS AND RESULTS: First, we determined the MIC of ascorbate against Ps. aeruginosa strain PAO1, and all further experiments used concentrations below the MIC so that results could not be caused by reduced viability. Tests of subinhibitory concentrations of sodium ascorbate on cell signals were performed using a reporter strain assay. Sub-MICs of sodium ascorbate resulted in significant reduction of the signalling molecules C4-HSL and 3-oxo-C12-HSL (P < 0·01). The influence of sub-MIC of sodium ascorbate on virulence factors was also determined and ascorbate treatment led to significant depression of elastase, protease and haemolysin activities. In addition, inhibition of pyocyanin production, attenuation of biofilm formation and alteration of Pseudomonas motility was observed. Analysis by RT-PCR tested the effect of ascorbate on the expression of QS regulatory genes. Expression of QS regulatory genes, lasI, lasR, rhlI, rhlR, pqsR and pqsA, was repressed compared to untreated Ps. aeruginosa PAO1, confirming that ascorbate QS inhibition works on gene expression at the molecular level. CONCLUSION: Sodium ascorbate, even at low concentrations, inhibited QS and related virulence factors of Ps. aeruginosa PAO1. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated that sodium ascorbate could function as signal modulator and virulence inhibitor in Ps. aeruginosa.

The sequelae of herpes zoster.

BACKGROUND: The last 40 years was a period during which the incidence of herpes zoster appears to have increased substantially. OBJECTIVE: To determine whether the risk of complications of herpes zoster has changed during the last 40 years. METHODS: The automated medical records of a health maintenance organization were screened for diagnosis codes suggesting herpes zoster and potentially complicated cases of zoster. The predictive value of a herpes zoster diagnosis was calculated from sampling full-text records. Records of all patients with codes suggesting complications were reviewed in full. RESULTS: Of 859 individuals with herpes zoster who met the eligibility criteria, 101 were identified who experienced at least 1 complication, corresponding to a 60-day risk of 12%. Corrected for the sensitivity of the complication-finding strategy, the risk estimate was 14%. Risk increased markedly with age, with those older than 64 years having more than 6 times the risk of complications of those younger than 25 years (odds ratio, 8.3; 95% confidence interval, 2.5-29.3). Trigeminal distribution of rash and the presence of certain conditions associated with immune compromise appeared to increase risk. CONCLUSIONS: The apparent increase in the incidence of herpes zoster was not accompanied by a change in the risk of specific or overall complications in a population-based sample. Advanced age and other conditions associated with waning cellular immunity may confer an increased risk of experiencing a complicated course of herpes zoster.

Risk factors for postherpetic neuralgia.

BACKGROUND: The risk factors for postherpetic neuralgia (PHN), the most common complication of herpes zoster, have not been well established. OBJECTIVE: To elucidate the risk factors for PHN. METHODS: Automated medical, claims, and pharmacy records of a health maintenance organization were used to identify cases of PHN and obtain data on risk factors. A case-base design was used to assess the impact of various patient, disease, and treatment factors on the prevalence of PHN 1 and 2 months after developing zoster. RESULTS: There were 821 cases of herpes zoster that met all eligibility criteria. The prevalence of PHN more than 30 days after onset of zoster was 8.0% (95% confidence interval [CI], 6.3%-10.1%) and 4.5% (95% CI, 3.2%-6.2%) after 60 days. Compared with patients younger than 50 years, individuals aged 50 years or older had a 14.7-fold higher prevalence (95% CI, 6.8-32.0) 30 days and a 27.4-fold higher prevalence (95% CI, 8.8-85.4) 60 days after developing zoster. Prodromal sensory symptoms and certain conditions associated with compromised immunity were also associated with PHN. Systemic corticosteroids before zoster and treatment of zoster with acyclovir or corticosteroids did not significantly affect the prevalence of PHN. CONCLUSIONS: Increased age and prodromal symptoms are associated with higher prevalence of PHN 1 and 2 months after onset of zoster. Overall, systemic acyclovir appears not to confer any protection against PHN, although benefit among elderly patients cannot be excluded.

Development and experience with an algorithm to evaluate suspected smallpox cases in the United States, 2002-2004.

Concerns that smallpox, an eradicated disease, might reappear because of a bioterror attack and limited experience with smallpox diagnosis in the United States prompted us to design a clinical algorithm. We used clinical features of classic smallpox to classify persons presenting with suspected smallpox rashes into 3 categories: those with high, those with moderate, and those with low risk of having smallpox. The classification guides subsequent diagnostic strategies, limiting smallpox laboratory testing to high-risk persons to minimize the number of false-positive test results. From January 2002 through June 2004, the Centers for Disease Control and Prevention (CDC) received 43 consultations regarding suspected smallpox cases. No patient was at high risk for having smallpox. One patient was tested for the presence of variola virus. Varicella was the diagnosis for 23 cases (53%). The algorithm worked well to guide clinical and public health responses to suspected smallpox cases. The poster is available from CDC, and an interactive version and laboratory protocol are available at http://www.bt.cdc.gov/agent/smallpox/diagnosis/riskalgorithm/index.asp. We recommend use of the algorithm in the United States and elsewhere.

Experimental type 2 herpes simplex ophthalmitis in the newborn rat.

An animal model for the study of type 2 herpes simplex virus (HSV2) ophthalmitis is described. Wistar rats were inoculated intracerebrally with HSV2 at 0, 5, 10, 15, 20, or 30 days of age. Eyes and brain from all animals, whether they survived or succumbed with encephalitis, were collected for microscopic and virologic studies. Up to 20% or more of the HSV2-inoculated rats had lesions in the cornea, uveal tract, and/or retina. Herpetic keratiis occurred in a few animals while the eyelids were still fused, indicative of internal spread of HSV2. Intranuclear inclusions were observed in corneal epithelium and neural retina, and herpesvirus particles were demonstrated in the cornea, iris, and retina. Lesions of the cornea and iris were also visualized by scanning electron microscopy. Virus was isolated from over 40% of the eyes tested. In general, titers of the virus in the eyes were less than those in the brains of HSV2-inoculated rats. The newborn rat thus represents another animal model to study herpetic ophthalmitis. Unlike most studies, ocular lesions were produced by a route other than the usual topical or intraocular inoculation of the virus.

Changes in testicular blood flow and testosterone production during aspermatogenesis after irradiation.

Exposure of the testes of anaesthetized adult rats to 527 rads of gamma-irradiation caused testis weight to fall slowly at first and then more rapidly from 21 days afterwards, reaching a minimum at 52 days, when spermatogenesis was severely disrupted. The weights of the accessory organs and the concentrations of testosterone in peripheral blood were slightly reduced; the concentrations in blood from the testicular veins were lower than control at shorter intervals after irradiation, but at later times tended to be similar or greater than control. Testicular blood flow per testis followed testis weight closely, and as a result the production of testosterone by the smaller testes (calculated as the product of plasma flow and the veno-arterial difference in testosterone concentration) was markedly reduced especially when the rats had been stimulated with human chorionic gonadotrophin (hCG). Serum FSH and LH rose appreciably as testis weight fell but there was a proportionately greater rise in FSH than LH, in comparison with surgically castrated animals. Increased amounts of extratubular, extracellular fluid were found in the aspermatogenic testes, but injection of hCG still caused increases in capillary permeability and the amount of fluid in the testis. These results indicate that during aspermatogenesis following irradiation (as with heat and efferent duct ligation) the capacity of the testes to secrete testosterone is severely limited by decreased testicular blood flow, not by the ability of the Leydig cells to release testosterone into their immediate environment.

Differential effects of gonadectomy on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour in rams.

Castrated sheep were used to study the effects of gonadectomy on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour. In the first experiment serum LH and FSH concentrations were determined in intact rams, recently castrated (2 days and 3 weeks) and long-term castrated animals (greater than 2 years, wethers) during intravenous testosterone infusion at physiological and supraphysiological levels. In intact rams, testosterone infusions effectively suppressed serum LH whilst FSH levels were suppressed only after prolonged infusion at the supraphysiological dose. Recently castrated sheep, which had higher gonadotrophin levels than intact rams, were less sensitive to testosterone feedback. Neither rate of testosterone infusion had any effect on the raised gonadotrophin levels in wethers. In a second experiment gonadotrophin concentrations and mating behaviour were determined in wethers bearing subdermal polydimethylsiloxane implants of testosterone, dihydrotestosterone and oestradiol. Testosterone implants stimulated mating behaviour in all wethers but suppressed gonadotrophins in only a proportion (three out of seven) of the animals. Both oestradiol and dihydrotestosterone suppressed LH and FSH in all wethers, whilst oestradiol, but not dihydrotestosterone, also stimulated mating behaviour. The present findings indicate that testosterone imposes continuing negative feedback on gonadotrophin secretion and that changes in the gonadotrophin regulatory system, which lead eventually to a loss in sensitivity to testosterone feedback, develop soon after gonadectomy. The results also provide the first direct evidence that longterm gonadectomy in male sheep has differential effects on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour.(ABSTRACT TRUNCATED AT 250 WORDS)

Varicella vaccine exposure during pregnancy: data from the first 5 years of the pregnancy registry.

OBJECTIVE: To assess the risks of congenital varicella syndrome and other birth defects in offspring of women who inadvertently received varicella vaccine during pregnancy or within 3 months of conception. METHODS: Pregnant women inadvertently exposed to varicella vaccine, reported voluntarily, were enrolled in the Pregnancy Registry for VARIVAX (Merck & Co., Inc., West Point, PA). The pregnancies were monitored and the outcomes ascertained from questionnaires completed voluntarily by the health care providers. The rates of congenital varicella syndrome and congenital anomalies were calculated for seronegative women prospectively reported to the registry. RESULTS: From March 17, 1995 through March 16, 2000, 362 pregnancy outcomes were identified from prospective reports. Ninety-two women were known to be seronegative to varicella, of whom 58 received their first dose of vaccine during the first or second trimester. No cases of congenital varicella syndrome were identified among 56 live births (rate 0%, 95% confidence interval [CI] 0, 15.6). Among all the prospective reports of live births, five congenital anomalies were reported. No specific pattern was identified in either the susceptible cohort or the sample population as a whole. CONCLUSION: No abnormal features have been reported that suggested the occurrence of congenital varicella syndrome or other birth defects related to vaccine exposure during pregnancy. Because of the small numbers, this study has limited precision, so continued surveillance is warranted. However, these results should provide some assurance to health care providers and women with inadvertent exposure before or during pregnancy.

Histology of fissures in human unerupted teeth.

An investigation into the contents of the fissures of unerupted teeth was made using light and scanning electron microscopy techniques. For this study, 193 unerupted teeth were used. The presence of ameloblasts in the fissures was substantiated, and their role in forming the fissure is discussed.

Histochemistry and scanning electron microscopy of tooth integumental material in humans.

Plaque material on human teeth was investigated using histochemical techniques and scanning electron microscopy. A positive reaction for protein, cargohydrate, and lipids was seen around the fissures and in a well-defined band around the sides of the tooth corresponding to the highest contour. These regions are the location of dense aggregates of bacteria as seen with scanning electron microscopy. This study emphasizes the fact that considerable attention should be given to the cleaning of not only the occlusal surfaces but also the highest contour of the tooth.

The effect of incisal bite force on condylar seating.

The purpose of this study was to investigate the relationship between different incisal biting forces and condylar seating. Bite force was measured with strain gauges at the incisors in 22 adult subjects. The subjects were positioned with mandibles in retruded centric and with an opening not exceeding the range of hinge axis movement. Condylar movement was measured using standard true hinge axis location procedures. Condylar position was measured with no force, then with bite forces of 4.5 kg, 7.5 kg and a comfortable maximum. Biting force significantly affected condylar movement (p < 0.001). As incisal bite forces increased, so did the amount of condylar seating to an average of 0.49 mm anteriorly and 0.27 mm superiorly using maximum biting force. Therefore, when taking a centric relation record, a technique involving an anterior stop and sufficient biting force should seat the condyles more fully.