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Biomedical subjects

John N Krieger

Publications and source records attributed to John N Krieger.

At least 19 recordsLinked to original sources
PubMed2007

Demographic and clinical characteristics of chronic prostatitis: prospective comparison of the University of Sciences Malaysia Cohort with the United States National Institutes of Health Cohort.

PURPOSE: We compared demographic and clinical characteristics of the University of Sciences Malaysia Chronic Prostatitis Cohort to the United States National Institutes of Health Chronic Prostatitis Cohort. MATERIALS AND METHODS: Participants met the same definition of chronic prostatitis/chronic pelvic pain syndrome. Each participant had extensive demographic, medical history, previous treatment, clinical and laboratory evaluations. RESULTS: The University of Sciences Malaysia and National Institutes of Health cohorts proved similar in most respects. National Institutes of Health-Chronic Prostatitis Symptom Index total scores, pain and urinary subscores were similar for the 332 University of Sciences Malaysia Chronic Prostatitis Cohort and 488 National Institutes of Health Chronic Prostatitis Cohort participants. Differences included worse quality of life subscore for the University of Sciences Malaysia Chronic Prostatitis Cohort, differences in the location, number of sites, and types of pain/discomfort between the 2 populations, and that the University of Sciences Malaysia participants had received less previous treatment. CONCLUSIONS: The demographic characteristics and clinical presentation of chronic prostatitis/chronic pelvic pain syndrome proved remarkably similar in these diverse populations. Both cohorts experienced major reduction in their quality of life from chronic pelvic pain and urinary symptoms. Comparison of diverse populations using standard clinical, laboratory and assessment instruments is feasible, and may provide important insights into chronic prostatitis/chronic pelvic pain syndrome and the factors that determine clinical outcome.

Adult↗
PubMed2006

Lower genitourinary tract sources of seminal HIV.

OBJECTIVE: To investigate genital tract sources of HIV-1, we conducted extensive genitourinary sampling of 23 seropositive men without urethritis who shed HIV in their seminal plasma. DESIGN: Semen was collected, then samples were obtained for HIV RNA in blood plasma, urethral fluid, pre-prostate massage fluid/urine (PMF/U) and post-PMF/U, and expressed prostatic secretions. Systematic transrectal ultrasound-guided prostate biopsies obtained from multiple prostate areas were evaluated for HIV RNA and DNA. RESULTS: Seminal HIV RNA levels correlated with HIV RNA levels in urethral fluid and post-PMF/U and with prostate biopsies HIV DNA, but not with expressed prostatic secretions HIV RNA. However, only the HIV RNA level in post-PMF/U independently predicted that in semen (2.77-fold change in semen for each 10-fold change in post-PMF/U; 95% confidence interval, 1.0-7.7) accounting for one third of the seminal HIV RNA level variation, irrespective of adjustment for antiretroviral therapy. CONCLUSIONS: These data indicate that distal genitourinary sources other than the prostate appear to be the major source of seminal HIV in men without clinical urethritis or prostatitis. Because the HIV RNA level in blood plasma is not reliable as an independent clinical predictor of virus levels in seminal plasma, these findings also extend the concept that the male genital tract is a distinct virological compartment from blood.

Adult↗
PubMed2006

Reliability and validity of the National Institutes of Health: Chronic Prostatitis Symptom Index in a Malaysian population.

The objective of the study is to determine the short- and long-term utility of the Chinese, Malay and English versions of the National Institutes of Health--Chronic Prostatitis Symptom Index (NIH-CPSI) in our ethnically diverse population. The NIH-CPSI was translated into Chinese and Malay, and then verified by back translation into English. Subjects included 100 new chronic prostatitis/chronic pelvic pain (CP/CPPS) patients, 71 new benign prostatic hyperplasia patients and 97 healthy individuals. Reliability was evaluated with test-retest reproducibility (TR) by calculating intraclass correlation coefficients (ICC). Internal consistency was evaluated by calculating Cronbach's alpha (alpha). Validity assessments included discriminant and construct validity. (Presented in the order of Chinese, Malay then English). ICC values for short-term (1 week) TR were 0.90, 0.80 and 0.89, while ICC values for long-term (14 weeks) TR were 0.54, 0.61 and 0.61. Cronbach's alpha values were 0.63, 0.62 and 0.57. The NIH-CPSI total score discriminated CP/CPPS patients (P<0.001) from the control groups with receiver operating curve values of 0.95, 0.98 and 0.94, respectively. Construct validity, reflected by the correlation coefficient values between the International Prostate Symptom Score and the NIH-CPSI of CP/CPPS patients were 0.72, 0.49 and 0.63 (all P<0.05). The Chinese, Malay and English versions of the NIH-CPSI each proved effective in our population. Short-term TR and discriminant validity were excellent for all three versions. However, long-term TR was only moderate, which might reflect variation in patients' perceptions of symptoms over time.

Adult↗
PubMed2005

Penile cancer: importance of circumcision, human papillomavirus and smoking in in situ and invasive disease.

Few population-based case-control studies have assessed etiologic factors for penile cancer. Past infection with high-risk human papillomavirus (HPV) is a known risk factor for penile cancer; however, few previous studies have related the HPV DNA status of the tumor to potential demographic and behavioral risk factors for the disease or evaluated whether in situ and invasive penile cancer share risk factors. Little information is available on the role and timing of circumcision in the etiology of penile cancer. We conducted a population-based case-control study in western Washington state that included 137 men diagnosed with in situ (n = 75) or invasive (n = 62) penile cancer between January 1, 1979, and December 31, 1998, and 671 control men identified through random digit dialing. Cases and controls were interviewed in person and provided peripheral blood samples. Case and control blood samples were tested for antibodies to HPV16 and HSV-2, and tumor specimens from cases were tested for HPV DNA. Men not circumcised during childhood were at increased risk of invasive (OR = 2.3, 95% CI 1.3-4.1) but not in situ (OR = 1.1, 95% CI 0.6-1.8) penile cancer. Approximately 35% of men with penile cancer who had not been circumcised in childhood reported a history of phimosis compared to 7.6% of controls (OR = 7.4, 95% CI 3.7-15.0). Penile conditions such as tear, rash and injury were associated with increased risk of disease. Among men not circumcised in childhood, phimosis was strongly associated with development of invasive penile cancer (OR = 11.4, 95% CI 5.0-25.9). When we restricted our analysis to men who did not have phimosis, the risk of invasive penile cancer associated with not having been circumcised in childhood was not elevated (OR = 0.5, 95% CI 0.1-2.5). Cigarette smoking was associated with a 4.5-fold risk (95% CI 2.0-10.1) of invasive penile cancer. HPV DNA was detected in 79.8% of tumor specimens, and 69.1% of tumors were HPV16-positive. The proportion of HPV DNA-positive tumors did not vary by any risk factors evaluated. Many risk factors were common for both in situ and invasive disease. However, 3 factors that did not increase the risk for in situ cancer proved significant risk factors for invasive penile cancer: lack of circumcision during childhood, phimosis and cigarette smoking. The high percentage of HPV DNA-positive tumors in our study is consistent with a strong association between HPV infection and the development of penile cancer regardless of circumcision status. Circumcision in early childhood may help prevent penile cancer by eliminating phimosis, a significant risk factor for the disease.

Adolescent↗
PubMed2005

Inconsistent localization of gram-positive bacteria to prostate-specific specimens from patients with chronic prostatitis.

OBJECTIVES: To determine the rate of gram-positive localizations and whether repetitive cultures demonstrate consistent localization of gram-positive bacteria in patients with chronic prostatitis symptoms. METHODS: We repeated localization cultures at different visits for untreated patients with chronic prostatitis symptoms. RESULTS: A total of 470 patients with chronic prostatitis had lower urinary tract localization cultures done. Ten-fold increases in the concentrations of gram-positive bacteria were noted when the postprostatic massage (VB3) or expressed prostatic secretions cultures were compared with first-void urine (VB1) cultures from 29 patients (6%). This was comparable to the 7% rate of gram-negative chronic bacterial prostatitis. We studied 49 patients who had undergone 130 repeated localization studies (median 2, range 2 to 4). Repeatedly negative studies were found in 20 patients, including 19 who each had undergone two studies and 1 who had undergone four studies. Of 9 patients who each had undergone three or four studies, 9 demonstrated localization of at least one gram-positive species. Of the 29 patients with gram-positive localizations, 27 (94%) did not have consistent localization of the gram-positive species. CONCLUSIONS: Patients with chronic prostatitis demonstrated localization of gram-positive bacteria, but the results were seldom reproducible in untreated patients. Gram-positive localizations may represent nonpathogens, transient bacterial colonization of the lower urinary tract, or intermittent shedding of prostatic pathogens. The limitations of traditional cultures highlight the need for better diagnostic approaches and improved recommendations for antimicrobial therapy.

Chronic Disease↗
PubMed2005

Pentosan polysulfate sodium therapy for men with chronic pelvic pain syndrome: a multicenter, randomized, placebo controlled study.

PURPOSE: We evaluated the efficacy and tolerability of pentosan polysulfate sodium (PPS) for the treatment of men with chronic pelvic pain syndrome (CPPS), National Institutes of Health (NIH) category III. MATERIALS AND METHODS: In a 16-week double-blind study 100 men with a clinical diagnosis of CPPS were randomized to receive 300 mg PPS or placebo 3 times daily. Clinical Global Improvement (CGI) was the primary outcome measure. Additional outcome measures were the NIH-Chronic Prostatitis Symptom Index (CPSI), Subjective Global Assessment and Symptom Severity Index assessment tools. RESULTS: Significantly more patients receiving PPS experienced moderate to marked improvement based on CGI assessment (18 or 37% vs 8 or 18%, p = 0.04). However, mean CGI scores were not significantly different between the PPS group (1.0) and placebo groups (1.0 vs 0.6, p = 0.107). All NIH-CPSI domains suggested a positive effect for PPS and for total NIH-CPSI the difference approached statistical significance (-5.9 or 22% vs -3.2 or 12%, p = 0.068). The PPS group showed significantly greater improvement in NIH-CPSI quality of life domain scores than the placebo group (-2.0 or 22% vs -1.0 or 12%, p = 0.031). Of patients receiving PPS 67% and 80% of those receiving placebo completed the 16-week study. Diarrhea, nausea and headache were the most common adverse events. CONCLUSIONS: Pentosan polysulfate (900 mg daily) was more likely than placebo to provide relief for CPPS symptoms.

Adolescent↗
PubMed2005

Adult male circumcision: results of a standardized procedure in Kisumu District, Kenya.

OBJECTIVE: To develop a standard procedure for male circumcision in a resource-poor medical setting and prospectively evaluate the outcome in a randomized, controlled trial with the incidence of human immunodeficiency virus (HIV) as the main outcome, as studies suggest that circumcision is associated with a lower incidence of HIV and other sexually transmitted infections in high-risk populations. SUBJECTS AND METHODS: Healthy, uncircumcised, HIV-seronegative men aged 18-24 years from Kisumu District, Kenya, were offered participation in a clinical trial using a standard circumcision procedure based on "usual" medical procedures in Western Kenya. The follow-up included visits at 3, 8 and 30 days after circumcision, with additional visits if necessary. Healing, satisfaction and resumption of activities were assessed at these visits and 3 months from randomization. RESULTS: Overall, 17 (3.5%) of the 479 circumcisions were associated with adverse events judged definitely, probably or possibly related to the procedure. The most common adverse events were wound infections (1.3%), bleeding (0.8%), and delayed wound healing or suture line disruption (0.8%). After 30 days, 99% of participants reported being very satisfied with the procedure; approximately 23% reported having had sex and 15% reported that their partners had expressed an opinion, all of whom were very satisfied with the outcome. About 96% of the men resumed normal general activities within the first week after the procedure. CONCLUSION: Safe and acceptable adult male circumcision services can be delivered in developing countries should male circumcision ultimately be advocated as a public-health measure.

Adolescent↗
PubMed2004

Short tandem repeat (STR) replacements in UTRs and introns suggest an important role for certain STRs in gene expression and disease.

Some untranslated sequence (UTR)-localized, short tandem repeats (STRs) exhibit evidence of selection pressure, including STR-coupling preferences, STR conservation, interspecies STR-STR replacements, and STR variants implicated in certain diseases. We wished to determine if STR replacements occurred near disease-related genes, including previously unstudied STRs as well as some STRs already implicated in disease. Among nine strong-candidate prostate cancer (CaP)-predisposing genes, three [steroid 5-alpha-reductase 2 (Srd5A-2), macrophage scavenger receptor-1 (MSR-1), and tumor necrosis factor receptor-21 (Tnfr-21)] exhibited striking STR replacements (P<0.001). The glomerular disease-related gene, CD2AP, exhibited an STR replacement flanked by well-conserved sequences, suggesting an STR-focused process. Another glomerular disease-related gene, rabphilin 3A, exhibited at least two STR replacements at the same UTR position comparing Drosophila melanogaster, Mus musculus, and Homo sapiens. Two genes implicated in blood-clotting disorders, von Willebrand factor (vWA) and fibrinogen alpha (FGA), exhibited multiple-intron STR replacements among mammals, extending STR replacement phenomena to introns. Among primates, a tyrosine hydroxylase (THO1) intron STR, previously implicated in both schizophrenia and drug withdrawal delirium, exhibited frequent replacements. Some STR replacements were early events in gene divergence. When STR sequences of closely related species were available, STR replacement was observed to be nearly as rapid as speciation. STR replacements expand the list of STR sequences that may contribute to genetic activity and to disease processes.

Animals↗
PubMed2004

Simple repeat replacements support similar functions of distinct repeats in inter-species mRNA homologs.

Simple repeats are ubiquitous in metazoan genomes, but function has been elusive. We reported that distinct, short tandem repeats (STRs) were coupled with rigorous polarity and register, suggesting order in simple repeat usage. Several STRs that lacked internal, canonical base pairs were associated with mRNAs encoding membrane functions and transcription factors. We hypothesized that diverse, simple repeats, such as (AC)n, (GU)n, (AG)n, (CU)n and (CUUU)n, had similar functions. The hypothesis predicts that closely related mRNAs would sometimes exhibit STR replacements. Comparing aquaporin 3 mRNAs, in rodents and humans, (GU)20 replaced (AG)29. Comparing biglycan mRNAs, (GU)25 replaced (CA)12. Comparing immunoglobulin superfamily member 9 mRNAs, the STR-couple, (CU)17(GU)9 replaced the STR-couple, (GU)19(GC)4. Comparing tumor necrosis factor receptor-21 mRNAs, (GU)24 replaced (CUUU)16. In a collection of 52 rodent-H. sapiens homologous mRNAs that had STRs, six (11.5%) STR-STR replacements occurred, significantly more than expected based on an STR frequency of 0.13% in all reported UTRs (p<0.001). Database studies and the observation of STR replacements among transcript homologs independently support the hypothesis that diverse repeat sequences, such as (AG)n, (AC)n, (GU)n, (CU)n and (CUUU)n, have similar usage that is consistent with analogous functions.

Animals↗
PubMed2004

Short tandem repeats are associated with diverse mRNAs encoding membrane-targeted proteins.

Within the genomes of multicellular organisms, short tandem repeating sequences (STRs) are ubiquitous, yet usage patterns remain obscure. The repeats (AC)n and (GU)n appear frequently in the untranslated regions (UTRs) of messenger RNAs (mRNAs). To investigate STR usage patterns, we used three approaches: (1) comparisons of individual mRNA database sequences including annotations and linked references, (2) statistical analysis of complete, UTR databases and (3) study of a large gene family, the aquaporins. Among 500 (AC)n- or (GU)n-containing mRNAs, 58 (12%) had known functions. Of these, 50 (86%) encoded proteins whose activities involved membranes or lipids, including integral membrane proteins, peripheral membrane proteins, ion channels, lipid enzymes, receptors and secreted proteins. A control sequence (AU)n also occurred in mRNAs, but only 5% encoded membrane-related functions. Investigation of all reported 3' UTR sequences, demonstrated that the STR (AC)n was 9 times more common in mRNAs encoding membrane functions than in the total UTR database (P < 0.001). Similarly, (GU)n was 8 times more common in membrane-function mRNAs than in the total database (P < 0.001). These observations suggest that (AC)n and (GU)n may be UTR signals for some mRNAs encoding membrane-targeted proteins.

3' Untranslated Regions↗
PubMed2004

Initial, long-term, and durable responses to terazosin, placebo, or other therapies for chronic prostatitis/chronic pelvic pain syndrome.

OBJECTIVES: To evaluate the initial, long-term, and durable response rates to terazosin, placebo, or other therapies in patients with chronic prostatitis/chronic pelvic pain syndrome. METHODS: A total of 100 subjects, aged 20 to 50 years, who met the National Institutes of Health criteria for chronic prostatitis/chronic pelvic pain syndrome and had not previously been treated with alpha-blockers, were entered in a 14-week, double-blind comparison of terazosin or placebo therapy. Nonresponders and responders with subsequent relapse were treated with terazosin or other medications (open label). The criterion for response was a score of 0 to 2 on the National Institutes of Health Chronic Prostatitis Symptom Index quality-of-life item. The initial response was evaluated at week 14, and the long-term response was evaluated after a median of 38 weeks (range 34 to 42), regardless of any additional treatment. A durable response was defined as an initial response without additional treatment. RESULTS: Of the 43 patients in the terazosin group, 24 (56%) had an initial response compared with 14 (33%) of 43 subjects in the placebo group (P = 0.03). Long-term responses were noted in 23 (56%) of 41 assessable subjects treated with terazosin initially compared with 12 (32%) of 38 assessable subjects treated with placebo (P = 0.03). Of the nonresponders and initial responders with relapse, 7 (41%) of 17 subjects responded to terazosin compared with 7 (21%) of 34 given other treatment (P = 0.12). Durable responses occurred in 18 (44%) of the 41 assessable patients treated initially with terazosin and in 6 (16%) of 38 treated initially with placebo (P = 0.01). CONCLUSIONS: Patients treated with terazosin were more likely to have initial, long-term, and durable responses than those treated with placebo.

Adrenergic alpha-Antagonists↗
PubMed2004

Identification and sequencing of bacterial rDNAs in culture-negative amniotic fluid from women in premature labor.

Our objective was to identify bacterial species present in culture-negative but 16S rDNA-positive amniotic fluid samples from women in preterm labor. Amniotic fluid from 69 women in preterm labor was cultured and examined for the proinflammatory cytokine interleukin-6 (IL-6). Polymerase chain reaction technology was used to detect highly conserved bacterial ribosomal DNA sequences (16S rDNAs). As previously reported, 16S rDNAs were identified in 15 (94%) of 16 culture-positive amniotic fluid samples, in 5 (36%) of 14 culture-negative samples with elevated IL-6, and in 1 (3%) of 39 culture-negative samples with low IL-6 levels. Direct sequencing was performed of 16S rDNAs from the 5 culture-negative amniotic fluid specimens with elevated IL-6, followed by database searches and phylogenetic analyses. The bacterial sequences identified included: two Leptotrichia sanguinegens, one human oral bacterium A33, one Fusobacterium nucleatum, and one Ureaplasma urealyticum. Identification and sequencing of 16S rDNAs in amniotic fluid is a promising technique to identify bacterial species associated with elevated IL-6 levels in culture-negative amniotic fluid that may contribute to the etiology of premature labor.

Adult↗
PubMed2004

Chronic prostatitis: Charlottesville to Seattle.

PURPOSE: Since few men with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) have culturable bacteria by traditional approaches, we used sensitive molecular methods to determine presence of fastidious microorganisms. MATERIALS AND METHODS: We evaluated 135 men with CP/CPPS by standardized clinical evaluation, and by lower tract localization cultures and chamber counts of expressed prostatic secretions of leukocytes. We excluded from study patients with bacteriuria, bacterial prostatitis, urethritis or positive urethral cultures. Prostate biopsy was obtained using a double-needle technique to limit contamination. We chose molecular approaches because previous studies had used culture antigen detection in urine, urethral swabs and expressed prostatic secretions. However, interpretation of such studies is complicated because urogenital samples often acquire bacteria while passing through the urethra. We used specific and broad-spectrum polymerase chain reaction (PCR) assays. RESULTS: Only 10 (8%) of the 135 subjects had positive specific PCR assays, including Mycoplasmia genitalium, Chlamydia trachomatis and Trichomonas vaginalis. Our findings suggested that C. trachomatis, T. vaginalis and M. genitalium may be identified in some patients with CP/CPPS, even among men with no evidence of urethritis and with negative urethral cultures and other assays. The broad-spectrum PCR assays provided the most provocative findings. DNA encoding tetracycline resistance was identified in 25% of subjects, and 77% of subjects had evidence of 16S rDNAs. The white blood cell concentration in the prostatic secretions correlated with identification of 16S rDNAs in prostate tissue (p <0.01). CONCLUSIONS: Delineating the precise role of these organisms in the etiology of CP/CPPS may help define better diagnostic and treatment algorithms.

Chronic Disease↗
PubMed2003

Transcribed short tandem repeats occur in couples with strongly preferred registers.

Short tandem repeats (STRs) have been widely observed, but most STRs have no recognized organization or function. Here we show that for diverse mRNAs, 84% of (GC)(n) repeats were found unexpectedly coupled with another STR, (GU)(n). These STR couples exhibited preferred polarity and register. In 3(') untranslated mRNA sequences (UTRs) 100% of (GC)(n>6) repeats were tightly coupled with (GU)(n). For (GC)(n), stem folding energy correlated with the length and number of neighboring, non-folding (GU)(n) partners (p=0.014). Approximately 20% of (AU)(n>/=14) repeats were coupled with (GU)(n). The STR couple (AC)(n)(AG)(n) also exhibited polarity and register preferences. The sequence arrangement at STR-couple joints was conserved rigorously, suggesting that these sequences were under selection pressure. Some STR couples may function as mRNA processing landmarks, based on alternative transcript comparisons. These observations suggest that some transcribed STRs may be functional UTR signals with predictable organization and usage patterns.

3' Untranslated Regions↗
PubMed2003

Application of real-time polymerase chain reaction technology to detect prostatic bacteria in patients with chronic prostatitis/chronic pelvic pain syndrome.

To investigate the potential association between prostate infection and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), we used molecular approaches described in previous reports. These methods employed standard polymerase chain (PCR) reaction assays to provide a qualitative evaluation of prostatic bacterial species. Here, we report on the detection of prostatic bacteria using a real-time PCR. Template DNAs were examined from prostatic tissue samples from patients with CP/CPPS. Two PCR primer sets were used: one that amplifies a portion of all known bacterial ribosomal DNAs (16S rDNAs) and one that is specific for Escherichia coli as opposed to related, E. coli-like bacteria. The 16S rDNA real-time PCR assay detected bacterial DNAs in eight (26%) of 31 samples from patients with CP/CPPS, including three samples (10%) that were also positive by the E. coli real-time PCR assay. These E. coli positives were quantified at approximately 10(3) cfu/ml of tissue digested. Quantification, speed and specificity make real-time PCR a promising approach for the quantitative detection and identification of prostatic bacteria from CP/CPPS patients.

Biopsy↗
PubMed2003

Epidemiology of prostatitis: new evidence for a world-wide problem.

We review new data on the epidemiology of chronic prostatitis. These population-based studies used reasonable case-definitions to survey various populations from North America, Europe and Asia. Overall, 2-10% of adult men suffer from symptoms compatible with chronic prostatitis at any time and approximately 15% of men suffer from symptoms of prostatitis at some point in their lives. Other epidemiologic data suggest that chronic prostatitis may be associated with an increased risk for development of benign prostatic hyperplasia and prostate cancer. These data suggest that chronic prostatitis is an important international health care problem that merits increased priority from clinicians and researchers.

Adult↗