An analysis of the association between prostate cancer risk loci, PSA levels, disease aggressiveness and disease-specific mortality.

BACKGROUND: Genome-wide association studies have identified multiple single-nucleotide polymorphsims (SNPs) associated with prostate cancer (PCa). Although these SNPs have been clearly associated with disease risk, their relationship with clinical outcomes is less clear. Our aim was to assess the frequency of known PCa susceptibility alleles within a single institution ascertainment and to correlate risk alleles with disease-specific outcomes. METHODS: We genotyped 1354 individuals treated for localised PCa between June 1988 and December 2007. Blood samples were prospectively collected and de-identified before being genotyped and matched to phenotypic data. We investigated associations between 61 SNPs and disease-specific end points using multivariable analysis and also determined if SNPs were associated with PSA at diagnosis. RESULTS: Seven SNPs showed associations on multivariable analysis (P<0.05), rs13385191 with both biochemical recurrence (BR) and castrate metastasis (CM), rs339331 (BR), rs1894292, rs17178655 and rs11067228 (CM), and rs11902236 and rs4857841 PCa-specific mortality. After applying a Bonferroni correction for number of SNPs (P<0.0008), the only persistent significant association was between rs17632542 (KLK3) and PSA levels at diagnosis (P=1.4 × 10(-5)). CONCLUSIONS: We confirmed that rs17632542 in KLK3 is associated with PSA at diagnosis. No significant association was seen between loci and disease-specific end points when accounting for multiple testing. This provides further evidence that known PCa risk SNPs do not predict likelihood of disease progression.

Genetic architecture of prostate cancer in the Ashkenazi Jewish population.

BACKGROUND: Recently, numerous prostate cancer risk loci have been identified, some of which show association in specific populations. No study has yet investigated whether these single nucleotide polymorphisms (SNPs) are associated with prostate cancer in the Ashkenazi Jewish (AJ) population. METHODS: A total of 29 known prostate cancer risk SNPs were genotyped in 963 prostate cancer cases and 613 controls of AJ ancestry. These data were combined with data from 1241 additional Ashkenazi controls and tested for association with prostate cancer. Correction for multiple testing was performed using the false discovery rate procedure. RESULTS: Ten of twenty-three SNPs that passed quality control procedures were associated with prostate cancer risk at a false discovery rate of 5%. Of these, nine were originally discovered in studies of individuals of European ancestry. Based on power calculations, the number of significant associations observed is not surprising. CONCLUSION: We see no convincing evidence that the genetic architecture of prostate cancer in the AJ population is substantively different from that observed in other populations of European ancestry.

Computational identification of noncoding RNAs in E. coli by comparative genomics.

Some genes produce noncoding transcripts that function directly as structural, regulatory, or even catalytic RNAs [1, 2]. Unlike protein-coding genes, which can be detected as open reading frames with distinctive statistical biases, noncoding RNA (ncRNA) gene sequences have no obvious inherent statistical biases [3]. Thus, genome sequence analyses reveal novel protein-coding genes, but any novel ncRNA genes remain invisible. Here, we describe a computational comparative genomic screen for ncRNA genes. The key idea is to distinguish conserved RNA secondary structures from a background of other conserved sequences using probabilistic models of expected mutational patterns in pairwise sequence alignments. We report the first whole-genome screen for ncRNA genes done with this method, in which we applied it to the "intergenic" spacers of Escherichia coli using comparative sequence data from four related bacteria. Starting from >23,000 conserved interspecies pairwise alignments, the screen predicted 275 candidate structural RNA loci. A sample of 49 candidate loci was assayed experimentally. At least 11 loci expressed small, apparently noncoding RNA transcripts of unknown function. Our computational approach may be used to discover structural ncRNA genes in any genome for which appropriate comparative genome sequence data are available.

Locoregional cancer treatment with magnetic drug targeting.

The specific delivery of chemotherapeutic agents to their desired targets with a minimum of systemic side effects is an important, ongoing challenge of chemotherapy. One approach, developed in the past to address this problem, is the i.v. injection of magnetic particles [ferrofluids (FFs)] bound to anticancer agents that are then concentrated in the desired area (e.g., the tumor) by an external magnetic field. In the present study, we treated squamous cell carcinoma in rabbits with FFs bound to mitoxantrone (FF-MTX) that was concentrated with a magnetic field. Experimental VX-2 squamous cell carcinoma was implanted in the median portion of the hind limb of New Zealand White rabbits (n = 26). When the tumor had reached a volume of approximately 3500 mm3, FF-MTX was injected intraarterially (i.a.; femoral artery) or i.v. (ear vein), whereas an external magnetic field was focused on the tumor. FF-MTX i.a. application with the external magnetic field resulted in a significant (P < 0.05), complete, and permanent remission of the squamous cell carcinoma compared with the control group (no treatment) and the i.v. FF-MTX group, with no signs of toxicity. The intratumoral accumulation of FFs was visualized both histologically and by magnetic resonance imaging. Thus, our data show that i.a. application of FF-MTX is successful in treating experimental squamous cell carcinoma. This "magnetic drug targeting" offers a unique opportunity to treat malignant tumors locoregionally without systemic toxicity. Furthermore, it may be possible to use these magnetic particles as a "carrier system" for a variety of anticancer agents, e.g., radionuclides, cancer-specific antibodies, and genes.

Effect of eight antiviral drugs on the reactivation of herpes simplex virus in explant cultures of latently infected mouse trigeminal ganglia.

The effect of several antiviral drugs on the reactivation of herpes simplex virus type 1 in explant cultures of latently infected mouse trigeminal ganglia was investigated. Phosphonoacetate and phosphonoformate, which act directly on the virus-induced DNA polymerase, require a drug concentration of 400 micrograms/ml for the inhibition of virus reactivation in latently infected ganglia. Arabinosyladenine and arabinosyladenine monophosphate, which are phosphorylated to triphosphates by cellular enzymes and inhibit virus synthesis either by blocking the DNA polymerase or by incorporation into viral DNA, require a concentration of only 100 micrograms/ml for the inhibition of the reactivation process. Drugs that are phosphorylated by the virus-induced thymidine kinase, such as acyclovir, arabinosylthymine, bromovinyldeoxyuridine, and three fluorinated pyrimidine nucleosides require the lowest drug concentrations for complete inhibition of virus reactivation in latently infected ganglia explant cultures. Our data suggest that the inhibition of virus reactivation is dependent not only on drug concentration, but also on the number of latently infected neurons in the ganglia.

Phosphonoacetic acid treatment of shope fibroma and vaccinia virus skin infections in rabbits.

The antiviral efficacy of phosphonoacetic acid (PAA) was studied in localized skin lesions of rabbits produced by the intradermal inoculation of vaccinia virus (VV) and of Shope fibroma virus (SFV). Systemic administration of PAA by intraperitoneal injections had no significant effect on the pustular lesions induced by VV or on the benign skin tumors caused by SFV. A complete suppression of the appearance of VV-induced pustular lesions was achieved by 2% PAA ointment applied twice daily for 4 days, starting 24 hr after virus inoculation. A significant effect against SFV-induced tumors was obtained by PAA ointment applied beginning either 24 or 72 hr after virus inoculation. A complete suppression of SFV-induced tumors was observed when a dose of 10 mg PAA was injected intralesionally once daily for 5 days, beginning treatment 24 hr after virus inoculation. A significant reduction of the intensity of the tumors was seen following the same treatment schedule but with a delay of 72 hr after virus inoculation or by reducing the length of treatment to 3 days or with a dose of 1 mg injected intradermally daily for 5 days. After the healing of the lesions, PAA-treated rabbits were resistant to reinfections to the same extent as those in which spontaneous healing had occurred.

Treatment of experimental latent herpes simplex virus infections with acyclovir and other antiviral compounds.

Acyclovir can prevent the establishment of latent herpes simplex virus (HSV) in sensory ganglia by early treatment of the primary infection in experimental animals. A delayed treatment may reduce the number of neurons that eventually become latently infected. Acyclovir can prevent virus reactivation in explant cultures of latently infected ganglia, experimentally induced recurrences of latently infected animals, and immunosuppressed patients. This effect is dependent on the continuous presence of the drug in the explant culture medium or organism. The treatment of recurrent lesions with acyclovir reduces the severity of the episode and may also prevent reinfection of ganglia, if this should be common in the maintenance of latency. It might be possible to eradicate a latent HSV, if conditions were created in which drugs such as acyclovir, activated by the virus-induced thymidine kinase, could interact with the enzyme before the assembly of mature virions.

Intravenous acyclovir therapy of first episodes of genital herpes: a multicenter double-blind, placebo-controlled trial.

PURPOSE: A collaborative multicenter double-blind, placebo-controlled trial of intravenous acyclovir treatment of first-episode genital herpes was performed in order to substantiate previous findings on the efficacy and safety of this drug, to evaluate the influence of parenteral therapy on recurrence frequency, and to obtain further data on the natural history of genital herpes. PATIENTS AND METHODS: Eighty-two patients with first episodes of genital herpes simplex virus (HSV) infection were randomly assigned in a double-blind fashion to treatment with intravenous acyclovir (5 mg/kg every eight hours) or placebo for five days. Before therapy, all lesions in the genital/perineal area and in extragenital sites were cultured. New lesions appearing in both areas after the onset of therapy were cultured separately. Lesions in all groups were cultured until completely healed. Sera were collected from all patients on entry to the study and on Day 21 to determine presence or absence of antibodies to HSV-1 and HSV-2. Time to healing, time to crusting, time to cessation of viral shedding, and appearance of new lesions during therapy were compared for each treatment group. RESULTS: Patients receiving acyclovir experienced a significant reduction in the median duration of pain (4.3 versus 4.8 days, p = 0.019), viral shedding (1.9 versus 8.4 days, p less than 0.001), and time to healing (8.4 versus 11.5 days, p = 0.02) compared with placebo recipients. These differences were largely attributable to the effect of therapy in the subset of patients with primary disease in whom acyclovir reduced the median duration of pain from 10.6 days to 4.2 days, the median duration of viral shedding from 17.1 days to 1.9 days, and the median time to healing from 14.2 days to 8.3 days. The rate of subsequent recurrence of genital herpes was not altered by acyclovir treatment: 24 of 32 acyclovir recipients (75 percent) experienced one or more recurrences during a mean follow-up of 14 months compared with 19 of 27 placebo recipients (70 percent). Among patients experiencing recurrences, the mean number of recurrences per month among acyclovir recipients was 0.25 compared with 0.19 for patients given placebo. CONCLUSION: This multicenter trial confirms the efficacy of intravenous acyclovir in the management of first-episode genital herpes, especially in patients with primary infection. However, therapy did not alter the frequency of recurrences.

Is myelomeningocele a disappearing disease?

The incidence of major congenital anomalies of the central nervous system was determined in a study of more than 233,000 births in Brooklyn, New York hospitals during the years 1968 to 1979. Anencephaly, myelomeningocele, and hydrocephalus occurred at frequencies of 47.1, 42.4, and 49.3 cases per 100,000 total births, respectively. During the 12 years of the study, the incidence of myelomeningocele decreased at a linear rate of approximately 4.6 cases per 100,000 births per year. A review of comparable reports on births in the northeastern region of the United States shows that a relatively consistent linear decline in myelomeningocele incidence has been proceeding at this rate for the past 50 years. It is concluded that minor local fluctuations and variability in data collection have obscured the steady decrease in occurrence. No significant declines were seen in the incidence rates of anencephaly or hydrocephalus, nor were uniform secular trends for these anomalies evident from previous reports. Epidemiologic differences between myelomeningocele and anencephaly are noted and their common etiology is questioned.

Effect of a thymidine kinase inhibitor (L-653,180) on antiviral treatment of experimental herpes simplex virus infection in mice.

Thymidine kinase (TK) inhibitors can block the activity of TK-dependent antiviral drugs in vitro. We have examined the ability of the TK inhibitor (+/-)-9-([(Z)-2-(hydroxymethyl)cyclohexyl] methyl)guanine (L-653,180) to prevent the therapeutic effect of acyclovir (ACV) in experimental herpes simplex virus type 1 (HSV) skin infections of mice. The results showed that ACV given in the drinking water prevents, in a dose-dependent way, the evolution of the viral infection, and that L-653,180 can reverse some of the therapeutic effects of the antiviral drug. Among the parameters used to evaluate the effect of the TK inhibitor mortality was increased compared to ACV treatment alone, only in the presence of low doses of ACV, whereas the establishment of latent infections in sensory ganglia was significantly increased compared to ACV treatment alone, even when high doses of ACV were administered together with L-653,180.

Arabinosyladenine monophosphate in genital herpes: a double-blind, placebo-controlled study.

A double-blind, placebo-controlled study was performed in 55 male patients with recurrent herpes simplex genitalis. The 29 patients who received topical arabinosyladenine monophosphate (ara-AMP) showed no significant difference in viral shedding, duration of pain, healing time or development of new lesions as compared to 26 placebo-treated patients. Ara-AMP was well-tolerated when topically applied. Serum neutralizing antibody titers did not change significantly during the acute and convalescent periods of the patient's recurrent HSG attacks. We conclude that ara-AMP, when applied topically as a 10% gel five times a day within 24 h of onset of recurrent HSG, does not influence the virologic and clinical evolution of the recurrent episode.

Photorefractive keratectomy for hyperopic and mixed astigmatism.

BACKGROUND: The correction of astigmatism with photorefractive keratectomy has been recommended in simple and myopic astigmatism. Therefore in this study the excimer laser was used to correct compound hyperopic and mixed astigmatism. METHODS: We present a prospective clinical study of photorefractive keratectomy in 30 eyes of 24 patients with compound hyperopic astigmatism with a mean spherical equivalent of +4.30 D and mean astigmatism of 2.33 D (group I) and in 17 eyes of 15 patients with mixed astigmatism with a mean spherical equivalent refraction of +0.46 D and mean astigmatism of 4.75 D (group II). The excimer laser used in this study was an MEL 60 (Aesculap-Meditec). In both groups an 18-month follow-up study was performed. RESULTS: In the compound hyperopic astigmatism group after 18 months, 14 of 17 treated eyes (82.3%) were within +/-1.00 D, and 11 (64.7%) were within 60.50 D of the intended correction. In the mixed astigmatism group after 18 months, 10 of 11 eyes (90.9%) were within +/-1.00 D, 8 eyes (72.7%) were within +/-0.50 D of the intended correction. In regard to the stability the 1 year regression of spherical equivalent in the compound hyperopic astigmatism group is 0.78 D and in the mixed astigmatism group 0.37 D. At 18 months, spectacle corrected visual acuity in the compound hyperopic astigmatism group was unchanged or improved in 14 eyes (87.5%); 2 eyes (12.5%) had lost one line. In the mixed astigmatism group at 18 months, spectacle corrected visual acuity was unchanged or improved in 9 eyes (81.8 %); 2 eyes (18.1%) lost one line. Preoperatively, the mean uncorrected visual acuity was 20/100 in the compound hyperopic astigmatism group and the mixed astigmatism group. At 18 months, 14 eyes (93.3%) in the compound hyperopic astigmatism group had an uncorrected visual acuity of 20/40 or better; 4 (26.6%) eyes had an uncorrected visual acuity of 20/20 or better. In the mixed astigmatism group, 9 (81.8%) eyes had an uncorrected visual acuity of 20/40 or better; 4 (36.3%) eyes had an uncorrected visual acuity of 20/20 or better. CONCLUSION: Photorefractive keratectomy is an efficient and relatively safe procedure for reducing or eliminating compound hyperopic and mixed astigmatism up to 6.00 D.

Established latent herpes simplex virus infections of mice not affected by adenosine monophosphate treatment.

Hairless mice with established latent herpes simplex virus infections in their trigeminal ganglia were treated for different time intervals with various doses of adenosine monophosphate. The treatment did not eliminate the latent infection and the results suggest that the drug did not reduce the amount of reactivatable virus present in latently infected ganglia. It appears therefore that adenosine monophosphate exerts its antiviral effects through non-specific mechanisms.

Effect of immune serum on the establishment of herpes simplex virus infection in trigeminal ganglia of hairless mice.

Administration of immune serum to herpes simplex virus (HSV)-infected hairless mice could not prevent acute infection in the trigeminal ganglia and the eventual establishment of latency. However, immune serum reduced the amount of free virus in the ganglion during the acute phase of the infection. It appears also that the amount of virus that can be reactivated in the latently infected ganglion is decreased. This was indicated by a prolonged reactivation time and by a reduced virus content of ganglion homogenates prepared after various periods of cocultivation.

Reinfections and site-specific immunity in herpes simplex virus infections.

Studies with human volunteers and patients suffering from recurrent herpes simplex virus (HSV) infections have shown that reinfections with autologous or heterologous strains, occurring at sites distant from those of the recurrences, are possible in a variable proportion of the subjects. Experiments in animals have shown that mice surviving a primary HSV infection in the lumbo-sacral area, can become latently infected in trigeminal ganglia upon reinfection of the orofacial site. Similar results were obtained after vaccination of mice with a thymidine-kinase negative, non-pathogenic HSV-1 mutant. It was also demonstrated that initial HSV-1 eye infection in rabbits prevents superinfection of trigeminal ganglia by other strains.

Isolation of herpes simplex virus clones and drug resistant mutants in microcultures.

Suitable dilutions of herpes simplex virus (HSV) preparations inoculated into microcultures of confluent monolayers of human foreskin or Vero cells, in individual wells of plastic "microplates", induced viral cytopathic effects that resulted from the infection of the cultures by single virus particles. The clonal nature of the viral progeny in isolated wells was supported by visual control over the development of viral foci and by statistical analysis. The method has the advantage of speed and economy, while it also yields a large primary clonal virus stock. HSV clones resistant to phosphonoacetic acid (PAA) and 5-iodo-2'-deoxyuridine (IUdR) could be readily isolated by the described technique.

Initiation and maintenance of latent herpes simplex virus infections: the paradox of perpetual immobility and continuous movement.

During the acute phase of infection, herpes simplex virus (HSV) is taken up by nerve endings and travels, probably as a noninfectious nucleocapsid, toward the neurons of sensory ganglia. Infectious virus can be detected in ganglia for a limited period, after which the virus enters into a latent phase. It appears that synthesis of deoxyribonucleic acid is not required and that an early viral protein and at least one additional late virus gene product are involved in the establishment of latency. The distinction between a "static" and a "dynamic" form of latency depends on the ability to detect viral activities in neurons and on whether these observed activities are expressed continuously or intermittently. The development of recurrent lesions following virus reactivation is an occasional event and is controlled by inducing agents and the state of the organism. The maintenance of latency depends on the number of neurons that become latently infected after the primary episode, the number of neurons in which reactivation takes place, the fate of the neuron after virus reactivation, and the possibility of renewed neuronal infections after each recurrent episode. Exogenous reinfections may also contribute to the maintenance of latency since they can lead to latent infections in nearby or distantly located sensory ganglia. Multiple latent infections may result also from a single primary infection by dissemination of the virus to distantly located ganglia.

Spread of herpes simplex virus in lymph nodes after experimental infection of mice.

Herpes simplex virus was frequently isolated from ipsilateral popliteal lymph nodes after percutaneous inoculation of the dorsal face of the footpad, and from ipsi- and contralateral submandibular lymph nodes after percutaneous inoculation of the cheek or the orofacial area of mice. Virus was detected only on very rare occasion in nondraining lymph nodes (inguinal or axillary) or in contralateral popliteal lymph nodes, but was frequently isolated in contralateral lumbar lymph nodes after footpad inoculation. The presence of virus in lymph nodes paralleled or followed the invasion of ipsilateral sensory ganglia and was associated with dissemination of virus in contralateral sensory ganglia after unilateral inoculation. In older mice virus was detected only occasionally in lymph nodes and dissemination of virus in contralateral sensory ganglia was generally not observed. The results suggest that lymphatic spread may contribute to dissemination of virus in contralateral sensory ganglia after unilateral inoculation of mice.