In vitro culture of bovine IVM-IVF embryos: Cooperative interaction among embryos and the role of growth factors

The objective of this study was to determine whether there is a cooperative interaction among bovine embryos during in vitro culture. Furthermore, culture medium was supplemented with the growth factors, epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1), to determine if these factors had a stimulatory effect on bovine embryo development similar to that seen in mouse development. In vitro matured - in vitro fertilized bovine embryos (2- to 8-cell) were cultured singly and in groups of five in 25 mul of medium (CR1 + amino acids + fatty acid-free bovine serum albumin) with or without EGF and TGF-beta1. Bovine embryos cultured in groups had a significantly higher rate of development to the blastocyst stage than embryos cultured singly. Neither EGF (10 ng/ml) nor TGF-beta1 (2 ng/ml) affected blastocyst development, hatching or the cell number of the embryos cultured in groups. Epidermal growth factor stimulated hatching of embryos cultured singly from the 8-cell stage, but did not significantly affect blastocyst development.

Production of cloned pigs from in vitro systems

Here we describe a procedure for cloning pigs by the use of in vitro culture systems. Four healthy male piglets from two litters were born following nuclear transfer of cultured somatic cells and subsequent embryo transfer. The initiation of five additional pregnancies demonstrates the reproducibility of this procedure. Its important features include extended in vitro culture of fetal cells preceding nuclear transfer, as well as in vitro maturation and activation of oocytes and in vitro embryo culture. The cell culture and nuclear transfer techniques described here should allow the use of genetic modification procedures to produce tissues and organs from cloned pigs with reduced immunogenicity for use in xenotransplantation.

Exposure of the internal carotid artery near the skull base: the posterolateral anatomic approach

Internal carotid injuries in zone III near the base of the skull are technically the most challenging of the carotid injuries. Diagnostic angiography is important to evaluate the exact site and extent of injury and the presence or absence of prograde flow in the injured segment. Vascular repair in this area is highly dependent on the adequacy of surgical exposure. Previous approaches have emphasized displacement of the mandible either by subluxation or mandibulotomy. Problems related to mandibulotomy, such as intraoral contamination, infection, and nonunion, are potential complications of this approach to the high carotid artery. In addition, it does not give adequate exposure of the internal carotid artery at the critical area, near the base of the skull. Experience gained from the extended radical neck dissection exposing the internal carotid artery up to the skull base has demonstrated that a posterolateral anatomic approach can provide superior exposure of the high carotid artery with lower morbidity and shortened operative time. This surgical approach involves cutting the sternomastoid muscle close to the mastoid and dissecting all the tissues away from the surface of the mastoid. Dividing the posterior belly of the digastric and styloid group of muscles assists in exposure of the internal carotid artery. Rarely, dissection of the facial nerve and removal of the tail of parotid add additional access to this area. This article describes the stepwise anatomic approach to the internal carotid artery near the base of the skull.

Vertebral artery injury--diagnosis and management

The literature on vascular trauma contains little information on the management of vertebral artery injuries. We have reviewed our experience consisting of 23 patients with vertebral artery injuries caused by 19 gunshot wounds, two stab wounds, one shotgun wound, and one blunt injury. Twelve patients sustained unilateral vertebral artery thrombosis, seven patients had vertebral AV fistulae (three jugular vein, four vertebral vein) and four patients sustained mural injury without thrombosis. Six patients (26.1%) developed major neurologic deficits of which five could be directly attributed to CNS missile injury. One patient had transient vertebrobasilar ischemia on the basis of a vertebral AV fistula. Four of the seven vertebral AV fistulae were managed solely by therapeutic embolization and two patients early in the series underwent surgical management alone. One patient had therapeutic embolization of the proximal vertebral artery and operative distal vertebral artery ligation for an AV fistula. The four patients who died (17.4%) did so as a direct result of their CNS missile injury. We conclude that: 1) unilateral vertebral artery occlusion seldom results in a neurologic deficit if there is a normal contralateral vertebral artery and PICA (posterior inferior cerebellar artery) blood supply is preserved; 2) accurate assessment of a vertebral artery injury requires contralateral vertebral arteriogram; 3) management of vertebral artery injury is simplified by proximal, and if possible distal, therapeutic embolization; 4) an anterior approach to the C1-2 vertebral artery is a satisfactory method of obtaining distal surgical control, obviating the need to unroof the bony canal of the vertebral artery; 5) angiography is necessary in penetrating neck trauma to identify occult vascular injuries.

CT diagnosis of renal pedicle injury

The CT findings in 6 renal vascular injuries were reviewed. The most specific observations in traumatic renal arterial thrombosis were nonexcretion, "rim" enhancement, and abrupt termination of an enhanced renal artery. Other signs of a disrupted renal vascular pedicle included central retroperitoneal hematoma associated with limited perinephric hematoma causing lateral displacement of the kidney. We conclude that CT allows differentiation of the causes of the absent or poor urographic nephrogram after trauma and may obviate the need for time-consuming angiography. CT should replace excretory urography for the evaluation of polytrauma, especially when the mechanism of injury is compatible with pedicle disruption.