Murine neonatal intravascular injections: modeling newborn disease.

The ability to perform murine neonatal intravascular injections likely will prove useful in studying many newborn-specific disease states that are modeled in mice. Unfortunately, effective intravascular injection in the neonatal mouse has been limited by developmental immaturity and small size. To establish a mouse model of neonatal intravascular injection, C57Bl/6 pups between birth and 6 d of age were injected with a buffered solution containing cells or vehicle alone. For both external jugular and superficial temporal vein injections, a 2-member team was used to position the pup, insert the needle, and perfuse the injectate. For superficial temporal vein injections, the vascular anatomy was visualized by using transillumination. After injection into the jugular or superficial temporal vein, the survival rate to adulthood was 100% (n = 30 pups per group), with no long-term complications. Occasional extravasation of injectate was well tolerated, allowing for serial injections (n = 40 pups). Intravascular access was confirmed by using fluorescent dye perfusion studies and cellular engraftment analysis. The 2 techniques are safe and reproducible methods of obtaining intravascular access via the external jugular and superficial temporal veins in newborn mice. These methods provide a mechanism for delivering a wide variety of substances, ranging from aqueous solutions to suspensions.

Spontaneous pulmonary interstitial emphysema in a term unventilated infant.

Pulmonary interstitial emphysema (PIE) is a form of air block most frequently seen in ventilated preterm infants with severe lung disease; it is rarely reported in spontaneously breathing term infants. We report on an infant previously diagnosed with laryngomalacia and congestive heart failure and with evidence of antenatal stroke before the onset of pulmonary disease. He presented at 6 weeks of age with spontaneous pneumothorax. Focal cystic changes were seen on imaging studies of the lungs. There was no prior history of mechanical ventilation. Prior chest X-rays did not show cystic changes. He subsequently underwent resection of the affected lung areas. Pathologic examination revealed persistent PIE with cystic expansion, pleural blebs, and reactive pleuritis, as well as subpleural air-space enlargement. The patient did well postoperatively and was discharged home without further problems. This case demonstrates that PIE can occur in an infant without any history of mechanical ventilation, suggesting the need for a high index of suspicion for PIE, even in nonventilated and spontaneously breathing term neonates. PIE should be included in the differential diagnosis of cystic lung lesions in all young infants.

[The results of surgical treatment for cryptorchidism at Landspitalinn, 1970-1993.].

OBJECTIVE: Cryptorchidism is a common congenital genito-urological anomali in males with increased risk of infertility and testicular cancer. In this retrospective study the results of operations for undescended testis at Landspitalinn University Hospital were reviewed with special emphasis on patients diagnosed with testicular cancer later in life. MATERIAL AND METHODS: The study includes 593 males with undescended testis who were operated on between 1970 and 1993. Information was gathered from hospital records, including birth-weight, age at diagnosis and operation, localization of the testes and complications to surgery. Information on patients diagnosed with testicular cancer was aquired from the Icelandic Cancer Registry. RESULTS: The average birth-weight was 3461 g, including 58 boys (10%) with low birth-weight (