A Novel Firefly Algorithm for Optimal Linear Phase FIR Filter Design

Optimal digital filter design in digital signal processing has thrown a growing influence on communication systems. FIR filter design involves multi-parameter optimization, on which the existing optimization algorithms do not work efficiently. For which different optimization techniques can be utilized to determine the impulse response coefficient of a filter and try to meet the ideal frequency response characteristics. In this paper, FIR low pass, high pass, band pass and band stop filters have been designed using a new meta-heuristic search method, called firefly algorithm. Firefly Algorithm is inspired by the flash pattern and characteristics of fireflies. The performance of the designed filters has been compared with that obtained by real coded genetic algorithm (RGA), standard PSO and differential evolution (DE) optimization techniques. Differential evolution (DE) is already one of the most powerful stochastic real-parameter optimization algorithms in current use. Here the firefly algorithm (FA) technique has proven a significant advantage. For the problem at hand, the simulation of designing FIR filters has been done and the simulation results demonstrate that Firefly algorithm is better than other relevant algorithms, not only in the convergence speed but also in the performance of the designed filter.

Effect of surfactants on phosphatase level of fresh water fish Labeo rohita

Alterations in the activity of enzymes Acid phosphatase (E.C.3.1.3.2) and Alkaline phosphatase (EC 3.1.3.1) in organs such as liver, gills and muscle of rohu following its exposure to surfactants viz. CTAB, SDS and Triton X-100 were analyzed. Different levels of exposure were given depending on the LC50 value of the surfactant used. Also, the influence of age and weight of the organisms was tested simultaneously. The activity of ACP in the tissues of fish exposed to all the three surfactants showed marked enhancement after exposure; the effect being highest in the liver followed by gill and muscle. Activity levels of ALP in different tissues of the fish exposed to the surfactants also showed an increase. Maximum increase was found in the liver followed by muscle, and gill. The increase in the levels of these enzymes indicates a stressful condition of the fish.

Availability of services for subjects of sexual assault in genitourinary medicine clinics

The aim of this study is to gain an understanding of the services available to subjects of sexual assault at genitourinary medicine (GU medicine) clinics throughout the United Kingdom, and to determine whether these services are adequate. By means of a questionnaire, consultants in 106 clinics provided information on the number of patients who reported sexual assault and the services available to them. The study found a marked regional variation in attendances by subjects of sexual assault. However, only a minority of clinics kept accurate data (36.7% regarding female victims and 37.75% regarding male victims). The number of subjects who were aged under 16 years was disproportionately high (under 16s: 6.9% of female victims and 1.2% male victims; 16 and over: 1.3% of female victims and 0.14% of male victims). This survey highlights deficiencies in services that need to be addressed by clinics, management and the speciality.

The IL-10 -1082G polymorphism is associated with clearance of HPV infection

The role of cytokines in protecting against human papillomavirus (HPV) and HPV-associated disease is not fully understood. We compared the frequency of the interleukin (IL)-10 polymorphism (G allele) at position --1082 and the distribution of GG/GA/AA genotypes among 116 HPV-positive women, grouped according to their cervical cytological profiles, with 119 HPV-negative controls with normal smears. No difference was observed in genotype frequency between the groups. Among women in the HPV-positive, smear-normal group, who were re-tested for HPV after 12 months, there was a significant inverse association between presence of at least one variant G allele (high activity) and HPV persistence (OR per G allele = 0.082 [95% CI 0.009-0.73], P= 0.001; after controlling for ethnicity). This association remained significant after controlling for age, smoking and hormonal contraception (OR = 0.028 [95% CI 0.001-0.66], P= 0.001). This preliminary study suggests that higher levels of IL-10 may prevent cervical neoplasia through their role in eliminating HPV.

Factors affecting vaginal pH levels among female adolescents attending genitourinary medicine clinics

OBJECTIVES

Vaginal pH is related to hormonal status, and adolescents experience disturbed hormonal patterns following menarche. We assessed hormonal factors and risk of abnormal vaginal pH and bacterial vaginosis (BV) among adolescents attending genitourinary medicine (GUM) clinics.

METHODS

In a cross sectional study adolescents within 5 years of menarche, < or =17 years, or with oligo-amenorrhoea were recruited. Vaginal pH and BV were assessed and among those not using hormonal contraceptives, estrone-3-glucuronide (E3G) and pregnanediol-3alpha-glucuronide (P3G) concentrations were measured.

RESULTS

Among 102 adolescents, 59.8% (61) had a high vaginal pH (>4.5), which was higher than the prevalence of BV, detected in 33% (34). No association was found between presence of sexually transmitted infections (STI) and vaginal pH. In logistic regression, after controlling for BV and condom use, vaginal pH was positively associated with cervical ectopy (OR = 2.5; 95% CI 1.0 to 6.6, p = 0.05) and STI treatment history (OR = 2.5; 95% CI 0.9 to 6.5, p = 0.07), and negatively associated with use of Depo-Provera (OR = 0.1; 95% CI 0.03 to 0.6, p = 0.003) and recent onset (<12 months) of sexual activity (OR = 0.2; 95% CI 0.1 to 0.7, p = 0.004). Among 23 adolescents not using hormonal contraceptives, a high pH occurred more often in abnormal compared to normal menstrual cycles (OR = 10.8; 95% CI 1.4 to 85.4; p = 0.026). E3G concentrations were inversely correlated with vaginal pH in the follicular phase (Spearman: r = 0.51; p = 0.024).

CONCLUSIONS

Ectopy and abnormal menstrual cycles are common features of adolescence. Their presence is associated with increased risk of abnormal pH, and may also predispose to BV.

Biological and hormonal markers of chlamydia, human papillomavirus, and bacterial vaginosis among adolescents attending genitourinary medicine clinics

OBJECTIVE

To assess maturity indices, menstrual patterns, hormonal factors, and risk of adolescent genital tract infections.

METHODS

Cross sectional study in three genitourinary medicine clinics. Females 17 years or less, within 5 years of menarche, or reporting oligo-amenorrhoea were screened for genital tract infections and menstrual cycle characteristics determined. The outcome measures were risk factors associated with chlamydia, human papillomavirus (HPV DNA) and bacterial vaginosis (BV), separately and pooled. Correlations between estrone-3-glucuronide (E3G) and pregnanediol-3alpha-glucuronide (P3G) hormone concentrations and chlamydia, HPV, and BV.

RESULTS

Among 127 adolescents, HPV was present in 64.4% (95% CI: 54.5 to 74.3), BV in 33.9% (19.1 to 34.5), and chlamydia in 26.8% (19.1 to 34.5). Breast maturity, oligomenorrhoea, and older gynaecological age were associated with lower risk of all infections. After adjustment for calendar age, race, and behavioural factors, gynaecological age remained significant (OR = 0.7, 0.6-0.9; p = 0.008). Behavioural risk factors differed by infection. Smoking was protective for HPV (OR = 0.1, 0.0 to 0.9; p = 0.007), and a recent new partner for chlamydia (OR = 0.3, 0.1 to 0.9; p = 0.024). Sex during menses was associated with increased BV risk (OR = 3.3, 1.5 to 7.2; p = 0.003). Chlamydia was higher among adolescents who used emergency contraception (2.5; 1.1 to 5.9, p = 0.029) and lower among those using condoms at last sex (OR = 0.3, 0.1 to 0.9; p = 0.015). Among 25 adolescents not using hormonal contraceptives, 15 had disturbed or anovulatory cycles. Chlamydia risk was inversely associated with P3G concentrations (Mann-Whitney; p = 0.05).

CONCLUSIONS

Adolescents engaging in high risk behaviour at a young gynaecological age are susceptible to multiple infections. Adolescent clinical assessment should include gynaecological age.

A major lung cancer susceptibility locus maps to chromosome 6q23-25

Lung cancer is a major cause of death in the United States and other countries. The risk of lung cancer is greatly increased by cigarette smoking and by certain occupational exposures, but familial factors also clearly play a major role. To identify susceptibility genes for familial lung cancer, we conducted a genomewide linkage analysis of 52 extended pedigrees ascertained through probands with lung cancer who had several first-degree relatives with the same disease. Multipoint linkage analysis, under a simple autosomal dominant model, of all 52 families with three or more individuals affected by lung, throat, or laryngeal cancer, yielded a maximum heterogeneity LOD score (HLOD) of 2.79 at 155 cM on chromosome 6q (marker D6S2436). A subset of 38 pedigrees with four or more affected individuals yielded a multipoint HLOD of 3.47 at 155 cM. Analysis of a further subset of 23 multigenerational pedigrees with five or more affected individuals yielded a multipoint HLOD score of 4.26 at the same position. The 14 families with only three affected relatives yielded negative LOD scores in this region. A predivided samples test for heterogeneity comparing the LOD scores from the 23 multigenerational families with those from the remaining families was significant (P=.007). The 1-HLOD multipoint support interval from the multigenerational families extends from C6S1848 at 146 cM to 164 cM near D6S1035, overlapping a genomic region that is deleted in sporadic lung cancers as well as numerous other cancer types. Parametric linkage and variance-components analysis that incorporated effects of age and personal smoking also supported linkage in this region, but with somewhat diminished support. These results localize a major susceptibility locus influencing lung cancer risk to 6q23-25.

Levels of the DNA adduct, N7-methyldeoxyguanosine, are associated with increased risk of failure of treatment of cervical intraepithelial neoplasia

OBJECTIVE

To determine whether exposure to methylating agents was a risk factor for treatment failure in women undergoing colposcopic examination.

METHODS

Nine hundred fifty-eight women attending for colposcopic examination after abnormal cervical smear test results were recruited into the study cohort. Information on demographic factors, smoking and other risk factors was obtained and a pre-treatment biopsy was taken and stored at -70 degrees C. After follow-up, cases who had treatment failure of cervical intraepithelial neoplasia (CIN) within 2 years following treatment were identified (n = 77) and matched to women with no treatment failure of CIN in this time period (controls, n = 154). DNA was extracted from the pre-treatment biopsies and levels of N7-methyl-deoxyguanosine (N7-MedG), a marker of exposure to methylating agents, were quantified as the ring-opened form of the base damage by a validated immunoslotblot assay.

RESULTS

Sufficient DNA for N7-MedG analysis was extracted from 61 subjects corresponding to 20 matched case control pairs. N7-MedG was detected in cervical DNA with levels ranging from non-detected (<0.1 micromol/mol dG) to 4.83 micromol/mol dG. N7-MedG levels were significantly higher in cases (geometric mean 0.99 micromol/mol dG) than controls (0.33 micromol/mol dG; P = 0.01). There were no associations between N7-MedG levels and HPV or smoking status. Log N7-MedG content, after adjustment for HPV status at time of treatment, was found to be significantly associated with increased risk of treatment failure (OR 5.74, 95% CI 1.05-31.23).

CONCLUSIONS

The association between pre-treatment levels of DNA damage induced by methylating agents and subsequent treatment failure implicates methylating agent exposure as a causative factor in treatment failure.

An outbreak no longer: factors contributing to the return of syphilis in Greater Manchester

BACKGROUND

In the past few years, increased diagnoses of syphilis have been reported in cities around Britain and Europe. Enhanced surveillance of cases began in 1999 to identify the epidemiology of this increase in Greater Manchester.

METHODS

Information was collected on all cases of syphilis newly diagnosed in genitourinary medicine (GUM) clinics in Greater Manchester between January 1999 and November 2002. The data collected included demographic information and information about other sexually transmitted infections, sexual behaviour, perception of risk of infection, and awareness of syphilis transmission.

RESULTS

The majority of cases identified were white homosexual men resident in Greater Manchester. Of the 414 cases diagnosed, 74% had either a primary or secondary stage of syphilis infection and 37% of cases were HIV positive. High numbers of individuals practised unprotected oral sex despite good awareness of the risk of infection with syphilis. There is evidence that the way people are meeting sexual contacts is changing, with increasing numbers meeting most of their partners through the internet.

CONCLUSIONS

These findings have implications for targeting interventions. The provision of rapid diagnostic and treatment services is likely to be key for the control of syphilis and potentially of subsequent increases in HIV in the region.

Chronic prostatitis/chronic pelvic pain syndrome: national survey of genitourinary medicine clinics

We sought to determine current practice in the diagnosis and management of chronic prostatitis/chronic pelvic pain syndrome (CPPS) in genitourinary medicine departments in the UK, using a detailed questionnaire survey. Evaluable responses were received from 147 (69%) clinics. Seventy-nine (54%) clinics reported seeing >10 new CPPS patients per year. A broad range of investigations was reported to be used in the diagnosis of CPPS. Whilst 89 (61%) clinics reported using the four-glass test in diagnosis, 46 (32%) reported using the test in >90% of patients with CPPS, and 42 (29%) reported never using the test. In the treatment, doxycycline or ciprofloxacin were reported to be first line treatment by 98% clinics, mostly in 4-6 week courses; however, great variation was recorded in second-line choices and use of non-antibiotic approaches. This survey demonstrates that patients with CPPS are regularly diagnosed and managed in genitourinary clinics in the UK, with wide variations in diagnostic and treatment practices.

Leishmania plasma membrane Mg2+-ATPase is a H+/K+-antiporter involved in glucose symport. Studies with sealed ghosts and vesicles of opposite polarity

Experiments from other laboratories conducted with Leishmania donovani promastigote cells had earlier indicated that the plasma membrane Mg2+-ATPase of the parasite is an extrusion pump for H+. Taking advantage of the pellicular microtubular structure of the plasma membrane of the organism, we report procedures for obtaining sealed ghost and sealed everted vesicle of defined polarity. Rapid influx of H+ into everted vesicles was found to be dependent on the simultaneous presence of ATP (1 mm) and Mg2+ (1 mm). Excellent correspondence between rate of H+ entry and the enzyme activity clearly demonstrated the Mg2+-ATPase to be a true H+ pump. H+ entry into everted vesicle was strongly inhibited by SCH28080 (IC50 = approximately 40 microm) and by omeprazole (IC50 = approximately 50 microm), both of which are characteristic inhibitors of mammalian gastric H+,K+-ATPase. H+ influx was completely insensitive to ouabain (250 microm), the typical inhibitor of Na+,K+-ATPase. Mg2+-ATPase activity could be partially stimulated with K+ (20 mm) that was inhibitable (>85%) with SCH28080 (50 microm). ATP-dependent rapid efflux of 86Rb+ from preloaded vesicles was completely inhibited by preincubation with omeprazole (150 microm) and by 5,5'-dithiobis-(2-nitrobenzoic acid) (1 mm), an inhibitor of the enzyme. Assuming Rb+ to be a true surrogate for K+, an ATP-dependent, electroneutral stoichiometric exchange of H+ and K+(1:1) was established. Rapid and 10-fold active accumulation of [U-(14)C]2-deoxyglucose in sealed ghosts could be observed when an artificial pH gradient (interior alkaline) was imposed. Rapid efflux of [U-(14)C]d-glucose from preloaded everted vesicles could also be initiated by activating the enzyme, with ATP. Taken together, the plasma membrane Mg2+-ATPase has been identified as an electroneutral H+/K+ antiporter with some properties reminiscent of the gastric H+,K+-ATPase. This enzyme is possibly involved in active accumulation of glucose via a H+-glucose symport system and in K+ accumulation.