Approach to the postnatal sonographic evaluation of prenatally detected abdominopelvic cysts.

Prenatally detected abdominal and pelvic masses are commonly cystic in morphology and usually seen on mid-trimester sonography. Sonography is the favored imaging modality for the postnatal evaluation of these lesions in newborns, given its availability, low cost, lack of ionizing radiation, lack of sedation, and high spatial resolution in small patients. The differential diagnosis of abdominopelvic cystic masses in newborns is broad given that they can arise from many organs and may have overlapping features on imaging. This article illustrates an approach to the postnatal sonographic evaluation of prenatally detected cystic abdominal and pelvic masses based on their anatomic location and distinctive sonographic characteristics, which can aid in an accurate diagnosis and guide appropriate management.

Early Vaginal Opening in Juvenile Female Rats Given BRAF-Inhibitor Dabrafenib Is Not Associated with Early Physiologic Sexual Maturation.

Dabrafenib (DAB), an inhibitor of BRAF kinase activity, is approved for metastatic melanoma with a BRAF V600E mutation. In support of pediatric cancer development, a nonclinical juvenile rat toxicity study was conducted in which females had early vaginal opening (VO). It was hypothesized that the early VO was not indicative of sexual maturation, but a result of a local effect on the vagina. An investigative study was conducted that mimicked the definitive study design, with rats given DAB or vehicle orally from Postnatal Day (PND) 7 to 35 and with necropsy subsets just before VO, at the first and second estrus, along with age-matched controls. Histopathology was performed on reproductive tissues, including immunohistochemistry for BRAF expression. VO occurred earlier in DAB females than in controls (PND 27.2 vs. 31.5); however, the timing of the first estrus was unaffected (PND 34.0 vs. 33.0). DAB-treated females evaluated just before VO (PND 22.0) had mostly immature reproductive tracts with no evidence of ovulation, similar to age-matched controls; however, DAB-treated females had keratinized and histologically open vaginas. Also, there was raised skin around the urogenital area, which correlated with hyperplasia/keratosis of the vulvar skin and keratinization of the distal vagina. BRAF expression (evaluated in controls) was localized to these tissues. Thus, early VO in rats given DAB likely represents a local effect accelerating vaginal keratinization to become open and not accelerated sexual maturation.

Effect of Age, Duration of Exposure, and Dose of Atrazine on Sexual Maturation and the Luteinizing Hormone Surge in the Female Sprague-Dawley Rat.

Atrazine (ATZ) was administered daily by gavage to pregnant female Sprague Dawley rats at doses of 0, 6.25, 25 or 50 mg/kg/day, either during gestation, lactation and post-weaning (G/L/PW cohort) to F1 generation female offspring or only from postnatal day (PND 21) until five days after sexual maturation (vaginal opening) when the estrogen-primed, luteinizing hormone (LH) surge was evaluated (PW cohort). Additional subgroups of F1 females received the vehicle or ATZ from PND 21-133 or from PND 120-133. Slight reductions in fertility and the percentage of F1 generation pups surviving to PND 21 in the gestationally exposed 50 mg/kg dose group were accompanied by decreased food intake and body weight of dams and F1 generation offspring. The onset of puberty was delayed in of the F1 generation G/L/PW females at doses of 25 and 50 mg/kg/day. F1 generation females in the PW high-dose ATZ group also experienced a delay in the onset of puberty. ATZ had no effect on peak LH or LH AUC in ovariectomized rats 5 days after sexual maturation, irrespective of whether the F1 generation females were treated from gestation onward or only peripubertally. There was no effect of ATZ treatment on the estrous cycle, peak LH or LH AUC of F1 generation females exposed from gestation through to PND 133 or only for two weeks from PND 120-133. These results indicate that developing females exposed to ATZ are not more sensitive compared to animals exposed to ATZ as young adults.

Impact of Early Postnatal NSAID Treatment on Nephrogenesis in Wistar Rats.

BACKGROUND: Prematurely born children with patent ductus arteriosus are treated with ibuprofen or indomethacin, which may inhibit kidney development. We determined whether clinical doses affected kidney development and function, with or without extrauterine growth retardation. METHODS: Wistar rats were cross-fostered in normal food (NF) or food restricted (FR) litters at postnatal day (PND) 2. On PND 3 to 4, three doses of 0.9% NaCl, 0.1 mg/kg indomethacin, or 10 mg/kg ibuprofen were administered via intraperitoneal injection with 12-hr intervals. Kidneys were evaluated for apoptosis, proliferation, and gene expression at PND 8; stereological assessment of nephron number at PND 35; and clinical pathology and neutrophil gelatinase-associated lipocalin at 4 and 9 months. Blood pressure was measured at the ages of 4, 6, and 9 months. RESULTS: NF and FR bodyweight differed from PND 3 onwards, ranging from 16.5 g at weaning (p < 0.001) to 39 g at necropsy (p = 0.019). Kidney proliferation/apoptosis ratios were 7:1 and 3:1 (p = 0.001), respectively and different expression of Wnt4 (0.7x), Oat1 (1.3x), Nphs1 (1.7x), and Aqp4 (1.3x) was noted (but its biological relevance doubted). Nephron numbers were decreased by 12% (p = 0.109) in the ibuprofen-NF group and 7.5% (p = 0.237) in FR groups. This coincided with a tendency to increased neutrophil gelatinase-associated lipocalin at 9 months. No differences were noted in electrolytes, creatinine, or urea clearance. No valid blood pressure results could be obtained. CONCLUSION: A clinical Ibuprofen dose showed potential to inhibit kidney development in neonatal rats. FR did not modulate these effects.