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C.K. Naughton

Dermatology Specialists

Publishes on Sperm and Testicular Function, Reproductive Biology and Fertility, Reproductive Health and Technologies. 81 papers and 3.3k citations.

81Publications
3.3kTotal Citations

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Top publicationsby citations

Varicocele and male infertility: Part II: Pathophysiology of varicoceles in male infertility
C.K. Naughton|Human Reproduction Update|2001
Cited by 399Open Access

Varicoceles are found in 19 to 41% of infertile men, and is one treatable form of male infertility. The mechanism by which varicoceles cause the variable effect on male infertility and spermatogenesis is still unknown. Experimental animal models play a useful (but limited) role due to the sudden and variable iatrogenic nature of the varicoceles and the duration of the studies. Much of the human data are derived by the characterization of associated differences in measurable parameters between men with and without varicoceles. The role of hyperthermia, testicular blood flow and venous pressure changes, reflux of renal/adrenal products, hormonal dysfunction, autoimmunity, defects in acrosome reaction, and oxidative stress, in the pathophysiology of varicocele will be discussed.

Glial Cell-Line Derived Neurotrophic Factor-Mediated RET Signaling Regulates Spermatogonial Stem Cell Fate1
C.K. Naughton, Sanjay Jain, Amy Strickland et al.|Biology of Reproduction|2005
Cited by 389

Normal spermatogenesis is essential for reproduction and depends on proper spermatogonial stem cell (SSC) function. Genes and signaling pathways that regulate SSC function have not been well defined. We report that glial cell-line-derived neurotrophic factor (GDNF) signaling through the RET tyrosine kinase/GFRA1 receptor complex is required for spermatogonial self-renewal in mice. GFRA1 and RET expression was identified in a subset of gonocytes at birth, was restricted to SSCs during normal spermatogenesis, and RET expressing cells were abundant in a cryptorchid model of SSC self-renewal. We used the whole-testis transplantation technique to overcome the limitation of neonatal lethality of Gdnf-, Gfra1-, and Ret-deficient mice and found that each of these genes is required for postnatal spermatogenesis and not for embryological testes development. Each mutant testis shows severe SSC depletion by Postnatal Day 7 during the first wave of spermatogenesis. These defects were due to lack of SSC proliferation and an inability of SSCs to maintain an undifferentiated state. Our results demonstrate that GDNF-mediated RET signaling is critical for the fate of undifferentiated spermatogonia and that abnormalities in this pathway may contribute to male infertility and testicular germ cell tumors.

Conditional Loss of <i>Nkx3.1</i> in Adult Mice Induces Prostatic Intraepithelial Neoplasia
Sarki A. Abdulkadir, Jeffrey A. Magee, Thomas Peters et al.|Molecular and Cellular Biology|2002
Cited by 269Open Access

The homeodomain-containing transcription factor NKX3.1 is a putative prostate tumor suppressor that is expressed in a largely prostate-specific and androgen-regulated manner. Loss of NKX3.1 protein expression is common in human prostate carcinomas and prostatic intraepithelial neoplasia (PIN) lesions and correlates with tumor progression. Disruption of the murine Nkx3.1 gene results in defects in prostate branching morphogenesis, secretions, and growth. To more closely mimic the pattern of NKX3.1 loss that occurs in human prostate tumors, we have used Cre- and loxP-mediated recombination to delete the Nkx3.1 gene in the prostates of adult transgenic mice. Conditional deletion of one or both alleles of Nkx3.1 leads to the development of preinvasive lesions that resemble PIN. The pattern of expression of several biomarkers (Ki-67, E-cadherin, and high-molecular-weight cytokeratins) in these PIN lesions resembled that observed in human cases of PIN. Furthermore, PIN foci in mice with conditional deletion of a single Nkx3.1 allele lose expression of the wild-type allele. Our results support the role of NKX3.1 as a prostate tumor suppressor and indicate a role for this gene in tumor initiation.

A PROSPECTIVE RANDOMIZED TRIAL COMPARING 6 VERSUS 12 PROSTATE BIOPSY CORES: IMPACT ON CANCER DETECTION
C.K. Naughton, David C. Miller, DOUGLAS E. MAGER et al.|The Journal of Urology|2000
Cited by 262

PURPOSE: Several studies suggest that sextant transrectal ultrasound guided biopsy of the prostate provides insufficient material to detect all clinically important prostate cancer, and obtaining more biopsy cores may improve the cancer detection rate. We performed a prospective randomized trial comparing 6 to 12 prostate biopsy cores to determine the impact on the cancer detection rate. MATERIALS AND METHODS: We prospectively randomized 244 men, including 71 (29%) black men, with a mean age plus or minus standard deviation of 65 +/- 8 years to undergo biopsy with 6 or 12 peripheral zone tissue cores. In our study subjects serum total prostate specific antigen (PSA) was between 2.5 and 20 ng./ml., and/or digital rectal examination was suspicious for cancer. All men completed a self-administered pre-biopsy and 2 post-biopsy questionnaires at 2 and 4 weeks. Cancer detection rates were compared in the groups and correlated with race, biopsy history, digital rectal examination findings, total PSA, transrectal ultrasound volume and PSA density, as determined by the formula, total PSA/transrectal ultrasound volume. RESULTS: The cancer detection rate in the 6 and 12 core groups was almost identical (26% and 27%, p = 0.9). There was no significant difference in cancer detection in the 2 trial arms with respect to subject race, biopsy history, digital rectal examination findings, total PSA, transrectal ultrasound volume or PSA density. However, our study did not have the statistical power to rule out small differences. CONCLUSIONS: The overall cancer detection rate is not materially increased by 12 core, peripheral zone biopsy in men in whom prostate cancer was mainly detected by screening.

Prevalence and Predictors of Sexual Problems, Relationship Stress, and Depression in Female Partners of Infertile Couples
Christian J. Nelson, A.W. Shindel, C.K. Naughton et al.|The Journal of Sexual Medicine|2008
Cited by 200

ABSTRACT Introduction Infertility has been associated with anxiety, stress, and sexual problems in both men and women. Aim To assess quality of life, sexual health, and depression in the female partner of infertile couples. Methods Couples presenting for the evaluation of infertility at two tertiary care medical centers were invited to participate in a survey study. Main Outcome Measures Female partners completed the Female Sexual Function Index (FSFI) and a modified Self-Esteem and Relationship (SEAR) Questionnaire. Male partners completed the SEAR and the International Index of Erectile Function (IIEF). Both partners completed the Center for Epidemiological Studies Depression Scale (CES-D) for depression and the Short Form-36 (SF-36) for general quality of life. Demographic, fertility, and comorbidity information was recorded. Results One hundred and twenty-one couples constitute the study population. Mean female and male age was 32 ± 5 and 35 ± 7 years, respectively. Most (92%) couples were married. Mean duration of relationship and marriage were 6.4 ± 3.9 and 3.8 ± 3.2 years, respectively. Mean duration of attempted conception was 24 ± 24 months. On CES-D, 19% of women had moderate and 13% had severe depression. Women reported significantly worse SF-36 Mental Health subscale scores (mean = 47.8, P &amp;lt; 0.05) compared with normative values. The mean total FSFI score was 28 ± 7 (maximum score of 36), with 26% of the women scoring below 26.55, an established cut-off for high risk of female sexual dysfunction. FSFI scores had a modest positive correlation with male IIEF scores (r = 0.37, P &amp;lt; 0.01), and there was a trend toward a negative correlation with female CES-D scores (r = −0.16, P &amp;lt; 0.06). These relationships were maintained on multivariate analysis. Conclusion Depression and sexual dysfunction are prevalent in female partners of infertile couples. Female sexual function is positively correlated with male partner sexual function in this population.