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.

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.

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.

The use of school-based vaccination clinics to control varicella outbreaks in two schools.

School-based vaccination clinics were offered in 2 schools experiencing varicella outbreaks. The clinics raised coverage of susceptible children from 52.9% to 92.2% and from 68.8% to 85.3% in the 2 schools, respectively. Although routine immunization and school-entry requirements are the best strategies for preventing outbreaks, school-based vaccination clinics may greatly increase coverage and shorten outbreaks.

Abscesses due to mycobacterium abscessus linked to injection of unapproved alternative medication.

An unlicensed injectable medicine sold as adrenal cortex extract (ACE*) and distributed in the alternative medicine community led to the largest outbreak of Mycobacterium abscessus infections reported in the United States. Records from the implicated distributor from January 1, 1995, to August 18, 1996, were used to identify purchasers; purchasers and public health alerts were used to identify patients. Purchasers and patients were interviewed, and available medical records were reviewed. Vials of ACE* were tested for mycobacterial contamination, and the product was recalled by the U.S. Food and Drug Administration. ACE* had been distributed to 148 purchasers in 30 states; 87 persons with postinjection abscesses attributable to the product were identified. Patient and vial cultures contained M. abscessus identical by enzymatic and molecular typing methods. Unusual infectious agents and alternative health practices should be considered in the diagnosis of infections that do not respond to routine treatment.

Reemergence of invasive Haemophilus influenzae type b disease in a well-vaccinated population in remote Alaska.

Before vaccination, Alaska Natives experienced very high rates of invasive Haemophilus influenzae type b (Hib) disease and carriage. Vaccination with Hib conjugate vaccine PRP-OMP (polyribosylribitol phosphate Neisseria meningitidis outer membrane protein) began in 1991 and resulted in a sharp decline in cases. In 1996, after switching to a different Hib conjugate vaccine, DTP-HbOC (which combines diphtheria-tetanus-whole cell pertussis vaccines with HbOC [Hib oligosaccharide CRM197]), cases of invasive Hib disease increased, suggesting ongoing Hib transmission despite widespread vaccination. To determine the prevalence of and risk factors for carriage, a cross-sectional study of oropharyngeal Hib carriage was conducted among Alaska Native children aged 1-5 years in remote southwestern Alaska. Of 496 children with swabs taken, 46 (9.3%) were colonized with Hib. Carriage rates varied by village from 2.2% to 13.2% and by age from 6.1% in 1-year-olds to 14.7% in 5-year-olds. Crowding was associated with Hib carriage. Widespread vaccination with PRP-OMP Hib conjugate vaccine did not eliminate carriage in this population of Alaska Natives, and ongoing carriage contributed to disease resurgence.

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.

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.

An in vitro evaluation of a visible light-cured resin as an alternative to conventional resin bonding systems.

An in vitro study of 69 premolars was conducted to evaluate a visible light-cured resin system used in orthodontic bonding. The material was evaluated under various parameters to determine its relative value as an alternative to the conventional chemically activated resin systems. The 30-hour bond strength for the visible light-cured resin system was approximately one half of that found for a chemically cured resin system. Initial 1-hour bond strength of the visible light-cured resin system was found to be only 26% of the 30-hour bond strength. Enamel loss associated with debonding and subsequent cleanup of the visible light-cured resin was approximately one half of that found with the chemically cured, heavily filled resin. With the visible light-cured resin system, cleanup of remaining resin required the use of hand scalers only.

An in vitro investigation of lingual bonding.

An in vitro investigation was undertaken to evaluate the bonding of orthodontic appliances onto lingual surfaces; 53 maxillary premolars, 37 mandibular premolars, and 37 mandibular incisors were used. Brackets were bonded onto the lingual and labial surfaces and fractured with an Instron machine. Enamel damage associated with debonding also was assessed. Results indicated comparable bond strengths (t test) on lingual (Li) and labial (La) surfaces: maxillary premolars--Li-138.2 kg/cm2, La-127.7 kg/cm2; mandibular premolars--Li-136.2 kg/cm2, La-121.6 kg/cm2; and mandibular incisors--Li-166.3 kg/cm2, La-161.1 kg/cm2. Adaptation of lingual bracket bases resulted in significantly higher lingual bond strengths for maxillary premolars (166.9 kg/cm2) and mandibular premolars (180.4 kg/cm2), but not for mandibular incisors (149.2 kg/cm2). On debonding, the percentages of lingual surfaces exhibiting horizontal "crescent-shaped" fracture lines and enamel fragment fractures were significantly higher (x2 test) than the corresponding percentages for labial surfaces: maxillary premolars--Li-67.9%, La-5.7%; mandibular premolars--Li-62.2%, La-13.5%; and mandibular incisors--Li-43.2%, La-18.9%. Furthermore, an increase in vertical enamel fracture lines (cracks) subsequent to debonding was seen labially and lingually. Bonding procedures for lingual surfaces should be identical to those advocated for labial surfaces. Care during debonding must be exercised to eliminate possible enamel damage.

Effects of local heating of the testes on the concentration of testosterone in jugular and testicular venous blood of rats and on testosterone production in vitro.

Heating both testes of rats to between 39 degrees C and 41 degrees C for 30 min was apparently without effect 21 days later, but heating to between 41.5 degrees C and 43 degrees C for 30 min resulted in a significant drop in testis weight accompanied by significant rises in the serum levels of LH and FSH. There were no changes in serum testosterone concentration in the peripheral circulation although there were increases in the concentration in testicular venous blood. The ability of the heated testis to secrete testosterone in vivo in response to maximal stimulation by hCG was reduced, as judged by testosterone levels in peripheral blood, while there was a supranormal increase in testosterone levels in testicular venous blood. Maximally stimulated testosterone production in vitro by the heated testis was supranormal whereas the basal production of testosterone per testis was not different from control values. Therefore, it appears that the testosterone produced by Leydig cells from heated testes may not be secreted as effectively as in normal testes.

Effects of local heating of the testis on testicular blood flow and testosterone secretion in the rat.

Exposure of one or both testes of rats to heating at 43 degrees C for 30 min resulted in a significant reduction in blood flow per testis, as measured using microspheres. The effects on the testes of unilateral and bilateral heating were similar, although the changes in FSH levels in peripheral blood were in general less marked after unilateral heating. Testicular blood flow fell, along with testicular weight, beginning at 2-4 days and reaching minimum values 14-21 days after heating. Both blood flow per testis and testicular weight were beginning to recover 35 days post-heating and blood flow per testis was normal by 56 days following heat treatment, although testicular weight was still slightly reduced at that time. Heating one or both testes to 42 degrees C produced similar but smaller responses 21 days later, whereas temperatures of 41 degrees C or lower were without effect on the parameters measured, except for some rises in serum LH and FSH. With slight reductions in blood flow, there were corresponding increases in testicular venous testosterone concentration so that testosterone secretion was unaffected. Further reductions in blood flow at 14 and 21 days after heating to 43 degrees C were not fully compensated by an increase in the concentration of testosterone in testicular venous blood, with the result that testosterone secretion fell.

Bonding to porcelain and gold.

To test the effectiveness of bonding orthodontic attachments to porcelain, edgewise brackets were bonded to 160 lower incisor, porcelain denture teeth by means of two different resin systems and three different porcelain bonding agents. Bonding to porcelain was found to be not only effective, but the use of a porcelain primer before bonding resulted in shear strengths comparable to those achieved with conventional acid-etch enamel bonding when the same resin was used. Roughening the porcelain surface and bonding with a heavily filled resin without a porcelain primer provided shear strengths (30.6 lbs) comparable to conventional acid-etch enamel bonding with a lightly filled resin (28.8 lbs). Roughening the porcelain surface before bonding, adding porcelain primers, and using highly filled resins all added significantly to bond strength, but caused a progressively greater risk of porcelain fracture during debonding. One of three methods to polish porcelain completely restored a roughened porcelain surface to its former appearance. The porcelain bonding primers failed to provide a significant increase in bond strength when bonding to gold. However, a roughened gold surface bonded with a heavily filled resin provided shear strengths (27.3 lbs). comparable to conventional acid-etch enamel bonding by means of a lightly filled resin (28.8 lbs). The use of a highly filled resin on an intact, glazed porcelain surface without using a porcelain primer may provide sufficient bond strength clinically. If more bond strength is needed, the use of Reliance porcelain primer on an intact glaze is preferable to Ormco porcelain primer or Fusion. Still greater bond strength can be developed by roughening the porcelain surface before application of a primer and use of a highly filled resin. The potential for porcelain fracture in debonding, however, is much increased and it is questionable whether bond strengths of this magnitude are required clinically.