Perinatal 'TORCH' infections identified by serology: correlation with abnormalities in the children through 7 years of age.

A matched case-control methodology was used to assess the risk for a wide range of abnormalities in children associated with serological evidence for 'TORCH' infections in the mothers. Specimens were selected from the large bank of sera from the approximately 54,000 pregnant women who participated in the Collaborative Perinatal Project. There was no clear association between any of the antigens studied and any specific damage to the child. These 'negative' findings are consistent with the absence of frequent significant effects due to these agents in the second and third trimesters of pregnancy.     

Psychological and clinical effects of renal biopsy performed using sedation

.A sedation regimen using sequential oral trinepazine, intravenous Pethco (pethidine, chlorpromazine and promethazine) and diazemuls was evaluated in children having native kidney (n = 17) and transplant kidney (n = 17) biopsies. Biopsy was successful in all cases, with no serious side effects. A self-reported scale of memory recall and pain perception showed the optimal time for biopsy to be between 30 and 90 min after the intravenous Pethco. The child’s level of distress was measured by a self-reported scale, a parent-reported scale and an observational scale for doctors and nurses; 45% of children rated themselves highly distressed prior to the procedure, their parents being the best assessors of this distress. Younger children and those undergoing native kidney biopsy had less understanding of the procedure. Children’s worries could be clearly categorised into procedural and outcome issues: those undergoing transplant biopsy were more worried about outcome, whereas those undergoing native kidney biopsy were more worried about the procedure. Received April 3, 1995; received in revised form and accepted April 17, 1996     

Use of vascular clips to approximate skin grafts

During excisions of acute burn wounds, attention to aesthetic detail often is secondary to the goal of rapid gross coverage. Expeditious approximation of adjacent skin grafts has long presented a problem to surgeons. Some surgeons simply place the grafts next to each other, relying on the intervening areas to "scar in". Others use staples to hold grafts together. These staples, however, can become buried under healed grafts and can cause "foreign body" reactions in the months and years ahead. In addition, staples cause bleeding beneath the newly placed grafts, contributing to hematoma formation. Still other surgeons suture or tape adjacent pieces of skin graft together, a tedious exercise. The cosmetic result of these techniques is often less than optimal resulting in the unfortunately familiar "patchwork quilt" appearance of grafts interweaved among scars. Vascular clips have proven to be useful for holding adjacent pieces of skin graft together.     

The extent of immunological privilege of orthotopic corneal grafts in the inbred rat

Corneal grafts are believed to enjoy a degree of "immunological privilege" primarily due to the avascularity of the recipient bed. In this study orthotopic full-thickness corneal grafts were carried out in the inbred rat, using a technique that is a close model of corneal grafting in humans. The survival times of corneal grafts on nonvascularized beds of 28 fully allogeneic strain combinations were determined without the use of immunosuppression. Some combinations were rejected rapidly, e.g. DA (RT1a) into BN (RT1n) with a mean survival time (MST) +/- SD of 7.8 +/- 1.3 days, and some at a moderate rate, e.g. AO (RT1u) into LEW (RT1l) with an MST of 23.1 +/- 10.0 days, whereas in other cases survival was indefinite, e.g. WAG (RT1u) into PVG (RT1c), an MST of greater than 100 days. Orthotopic corneal grafts on nonvascularized beds between DA and AO parents and the F1, followed the basic rules of transplantation genetics. In addition, the rate of graft rejection was significantly faster (P less than 0.001) with corneal grafts from DA into AO placed onto a vascularized compared with a nonvascularized corneal bed (MST of 6.8 +/- 2.4 or 12.1 +/- 4.0 days respectively). The rate of rejection of corneas on a vascularized bed was at a similar rate to that of orthotopic skin or heterotopic auxiliary heart grafts. The results indicate that the fate of a corneal allograft on a nonvascularized bed is dependent upon the particular combination of donor and recipient strain. No consistent association was observed between any donor or recipient RT1 haplotype and survival; this suggests that non-RT1 background genes may play a role in the survival of corneal grafts.     

Persistent Varicella-Zoster virus infection in a human rhabdomyosarcoma cell line and recovery of a plaque variant.

Varicella-zoster virus (VZV) has been found to persistently infect the human rhabdomyosarcoma cell line A204. Infectious center assays and fluorescent antibody staining demonstrated continuous production of infectious VZV and viral antigen. The level of infection determined by fluorescent antibody staining was variable, and usually only a small percentage of the cells were capable of producing plaques in permissive fibroblasts. The extent of infection was similar in cell cultures passaged at split ratios of 1:2 or 1:10 and grown at 33 or 37 degrees C. VZV recovered from A204 cells several months after establishment of the persistent infection had markedly increased syncytia-forming activity as compared with the parental VZV grown in human diploid fibroblast cells and the three monkey kidney-derived cell lines Vero, CV-1, and MA104. The expression of this altered phenotype continued after serial passage of the cell-associated virus in human diploid fibroblast and Vero cells. Consequently, we designated the reisolated VZV as plaque variant A. The buoyant densities of VZV plaque variant A and VZV DNAs in CsCl gradients were indistinguishable.     

Properties of implanted electrodes for functional electrical stimulation

Implanted wire electrodes are increasingly being used for the functional electrical stimulation of muscles in partially paralysed patients, yet many of their basic characteristics are poorly understood. In this study we investigated the selectivity, recruitment characteristics and range of control of several types of electrode in triceps surae and plantaris muscles of anaesthetized cats. We found that nerve cuffs are more efficient and selective (i.e., cause less stimulus spread to surrounding muscles) than intramuscular electrodes. Bipolar intramuscular stimulation was more efficient and selective than monopolar stimulation, but only if the nerve entry point was between the electrodes. Monopolar electrodes are efficient and selective if located close to the nerve entry point, but their performance declines with distance from it. Nonetheless, for a variety of reasons monopolar stimulation provides the best compromise in many current applications. Short duration pulses offer the best efficiency (least charge per pulse to elicit force) but high peak currents, increasing the risk of electrode corrosion and tissue damage. Electrode size has little effect on recruitment and should therefore be maximised because this minimises current density.