Cryptorchidism and puberty.

Cryptorchidism is the condition in which one or both testes have not descended adequately into the scrotum. The congenital form of cryptorchidism is one of the most prevalent urogenital anomalies in male newborns. In the acquired form of cryptorchidism, the testis that was previously descended normally is no longer located in the scrotum.

Deteriorating Semen Quality: The Role of the Environment.

Since the end of the last century, several reports have suggested that semen quality is declining, especially in Western countries. Furthermore, cross-sectional studies using similar protocols have suggested regional differences in semen quality of young and fertile men. Reasons for these regional differences and local adverse trends in semen quality are unknown, but environmental factors are suspected to have a role.

Pubertal testicular volume references for ruler, orchidometer, and ultrasonography measurements based on a longitudinal follow-up.

Background: Testicular volume is a marker of male pubertal development. Various clinical conditions and their treatments may influence testicular growth.

Objectives: To create ruler-based age-dependent pubertal testicular volume references that enable calculation of standard deviation (SD) scores.

What is the role of puberty in the development of islet autoimmunity and progression to type 1 diabetes?

In many populations, the peak period of incidence of type 1 diabetes (T1D) has been observed to be around 10-14 years of age, coinciding with puberty, but direct evidence of the role of puberty in the development of T1D is limited. We therefore aimed to investigate whether puberty and the timing of its onset are associated with the development of islet autoimmunity (IA) and subsequent progression to T1D. A Finnish population-based cohort of children with HLA-DQB1-conferred susceptibility to T1D was followed from 7 years of age until 15 years of age or until a diagnosis of T1D (n = 6920).

Environmental toxicants and male fertility.

Semen quality has declined especially among Western men. Experimental and epidemiological studies have shown potential links between exposure to environmental toxicants and poor male fertility. Some environmental exposures in utero can disrupt fetal testicular function and result in cryptorchidism, low semen quality, low serum testosterone levels, and low fertility.

Levels of persistent organic pollutants in breast milk samples representing Finnish and Danish boys with and without hypospadias.

Hypospadias is a congenital malformation of penile urethra with unknown etiology in most cases. Persistent organic pollutant (POP) exposure may disrupt endocrine function during a critical window of development of male genitalia. In animal studies, POPs have been associated with male reproductive disorders, including hypospadias, but only few studies have assessed this relationship in humans.

[C]carfentanil PET imaging for studying the peripheral opioid system in vivo: effect of photoperiod on mu-opioid receptor availability in brown adipose tissue.

Purpose: Photoperiod determines the metabolic activity of brown adipose tissue (BAT) and affects the food intake and body mass of mammals. Sympathetic innervation of the BAT controls thermogenesis and facilitates physiological adaption to seasonal changes, but the exact mechanism remains elusive. Previous studies have shown that central opioid signaling regulates BAT thermogenesis, and that the expression of the brain mu-opioid receptor (MOR) varies seasonally.

Reproductive Markers of Testicular Function and Size During Puberty in Boys With and Without a History of Cryptorchidism.

Context: Longitudinal data on levels of hypothalamic-pituitary-gonadal axis hormones and insulin-like growth factor I (IGF-I) during puberty in boys with a history of cryptorchidism are largely missing.

Objective: We aimed to compare pubertal hormone levels between boys with a history of congenital cryptorchidism who experienced spontaneous testicular descent or underwent orchiopexy and boys without a history of cryptorchidism.

Methods: This was a nested case-control study within a population-based birth cohort, with a prospective, longitudinal pubertal follow-up every 6 months (2005 to 2019).

[Ga]Ga-DOTA-Siglec-9 Detects Pharmacodynamic Changes of FAP-Targeted IL2 Variant Immunotherapy in B16-FAP Melanoma Mice.

Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible adhesion molecule, which supports contact between leukocytes and inflamed endothelium. There is evidence that VAP-1 is involved in the recruitment of leukocytes to melanoma tumors. Interleukin-2 (IL-2)-based immunotherapy is an efficient therapy that promotes immune system activity against cancers but is associated with toxicity.

Development of [F]AmBF Tetrazine for Radiolabeling of Peptides: Preclinical Evaluation and PET Imaging of [F]AmBF-PEG-Tyr-Octreotide in an AR42J Pancreatic Carcinoma Model.

Radiolabeled peptides have emerged as highly specific agents for targeting receptors expressed in tumors for therapeutic and diagnostic purposes. Peptides developed for positron emission tomography (PET) are typically radiolabeled using prosthetic groups or bifunctional chelators for fast "kit-like" incorporation of the radionuclide into the structure. A novel [F]alkylammoniomethyltrifluoroborate ([F]AmBF) tetrazine (Tz), [F]AmBF-Tz, was developed for the [F]fluorination of -cyclooctene (TCO)-modified biomolecules using Tyr-octreotides (TOCs) as model peptides.

Serum Testosterone Levels in 3-Month-Old Boys Predict Their Semen Quality as Young Adults.

Context: It remains unknown how the postnatal activation of the hypothalamic-pituitary-gonadal axis in infancy, also known as "minipuberty", relates to adult testis function.

Objective: To investigate how markers of reproductive function in 3-month-old boys correlate with adult reproductive health parameters.

Methods: This population-based birth cohort study (the Copenhagen Mother-Child cohort), conducted at Copenhagen University Hospital, Denmark, included 259 boys examined once around 3 months of age and again at 18 to 20 years.

Genetics of cryptorchidism and testicular regression.

Cryptorchidism, i.e., undescended testis, is one of the most common genital malformations in newborn male babies.

Determining the timing of pubertal onset via a multicohort analysis of growth.

Objective: Growth-based determination of pubertal onset timing would be cheap and practical. We aimed to determine this timing based on pubertal growth markers. Secondary aims were to estimate the differences in growth between cohorts and identify the role of overweight in onset timing.

Endocrine Disrupting Chemicals and Reproductive Health in Boys and Men.

Male reproductive health has declined as indicated by increasing rates of cryptorchidism, i.e., undescended testis, poor semen quality, low serum testosterone level, and testicular cancer.

Statistical Evaluation of Different Mathematical Models for Diffusion Weighted Imaging of Prostate Cancer Xenografts in Mice.

Purpose: To evaluate fitting quality and repeatability of four mathematical models for diffusion weighted imaging (DWI) during tumor progression in mouse xenograft model of prostate cancer.

Methods: Human prostate cancer cells (PC-3) were implanted subcutaneously in right hind limbs of 11 immunodeficient mice. Tumor growth was followed by weekly DWI examinations using a 7T MR scanner.

Docetaxel chemotherapy response in PC3 prostate cancer mouse model detected by rotating frame relaxations and water diffusion.

MRI is a common method of prostate cancer diagnosis. Several MRI-derived markers, including the apparent diffusion coefficient (ADC) based on diffusion-weighted imaging, have been shown to provide values for prostate cancer detection and characterization. The hypothesis of the study was that docetaxel chemotherapy response could be picked up earlier with rotating frame relaxation times T and T than with the continuous wave T , adiabatic T , adiabatic T , T , T or water ADC.

First-in-Humans Study of Ga-DOTA-Siglec-9, a PET Ligand Targeting Vascular Adhesion Protein 1.

Sialic acid-binding immunoglubulinlike lectin 9 (Siglec-9) is a ligand of vascular adhesion protein 1. A Ga-labeled peptide of Siglec-9, Ga-DOTA-Siglec-9, holds promise as a novel PET tracer for imaging of inflammation. This first-in-humans study investigated the safety, tolerability, biodistribution, and radiation dosimetry of this radiopharmaceutical.

Hypogonadism and Cryptorchidism.

Congenital cryptorchidism (undescended testis) is one of the most common congenital urogenital malformations in boys. Prevalence of cryptorchidism at birth among boys born with normal birth weight ranges from 1.8 to 8.

Testis Development.

Production of sperm and androgens is the main function of the testis. This depends on normal development of both testicular somatic cells and germ cells. A genetic program initiated from the Y chromosome gene sex-determining region Y (SRY) directs somatic cell specification to Sertoli cells that orchestrate further development.

Low-saturated-fat and low-cholesterol diet does not alter pubertal development and hormonal status in adolescents.

Aim: The aim was to assess the influence of dietary counselling on the pubertal development and hormonal status in healthy adolescents.

Methods: We used a subcohort of 193 healthy boys (52%) and girls (48%) from the Special Turku Coronary Risk Factor Intervention Project. Participants were recruited by nurses at the well-baby clinics in Turku Finland in 1990-1992 and randomised into intervention and control groups.

Comparison of Ga-DOTA-Siglec-9 and F-Fluorodeoxyribose-Siglec-9: Inflammation Imaging and Radiation Dosimetry.

Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a ligand of inflammation-inducible vascular adhesion protein-1 (VAP-1). We compared Ga-DOTA- and F-fluorodeoxyribose- (FDR-) labeled Siglec-9 motif peptides for PET imaging of inflammation. .

Adventures in radiosynthesis of clinical grade [Ga]Ga-DOTA-Siglec-9.

We finally managed to establish a protocol for generating Good Manufacturing Practice (GMP)-grade gallium-68-labelled 1,4,7,0-tetraazacyclododecane-1,4,7,10-tetraacetic acid conjugated sialic acid-binding immunoglobulin-like lectin 9 motif containing peptide ([Ga]Ga-DOTA-Siglec-9), the first radiopharmaceutical for positron emission tomography imaging of vascular adhesion protein 1.

Postnatal Changes in Testicular Position Are Associated With IGF-I and Function of Sertoli and Leydig Cells.

Context: Despite clinical guidelines calling for repetitive examination of testicular position during childhood, little is known of normal changes in testicular position during childhood, let alone factors that control it.

Objective: To assess changes in and factors associated with testicular position during childhood.

Design: Testicular position (the distance from the pubic bone to the upper pole of the testes) at birth, 3 months, 18 months, 36 months, and 7 years and reproductive hormones at 3 months were measured.

Pretargeted PET Imaging of -Cyclooctene-Modified Porous Silicon Nanoparticles.

Pretargeted positron emission tomography (PET) imaging based on bioorthogonal chemical reactions has proven its potential in immunoimaging. It may also have great potential in nanotheranostic applications. Here, we report the first successful pretargeted PET imaging of -cyclooctene-modified mesoporous silicon nanoparticles, using F-labeled tetrazine as a tracer.