Impotence and the use of the internal iliac artery in renal transplantation: a survey of surgeons' attitudes in the United Kingdom and Ireland

BACKGROUND

In 1996, a court in the United Kingdom ruled against a plaintiff who claimed that: (1) division of both internal iliac arteries at separate renal transplant operations had made him impotent and (2) the risk of his becoming impotent was sufficiently high that he should have been warned. The court ruled that there was not enough evidence in the medical literature to allow his claim to succeed.

METHODS

A survey of the views of transplant surgeons in the United Kingdom and Ireland on attitudes toward using the internal iliac artery for transplantation was conducted.

RESULTS

A 100% response rate was received. In a potent male patient, 11% of surgeons would never use the first internal iliac artery and 52% would use it infrequently. If one internal iliac artery had already been used, 61% would never use a second and 34% would use it infrequently. Eighty-nine percent believed the risk of impotence when the second internal iliac artery was used was 25% or higher, and 91% thought the risk should be explained to the patient.

CONCLUSION

A very strong opinion exists among transplant surgeons in the United Kingdom and Ireland that the second internal iliac artery should not be used to revascularize a kidney transplant when the first has already been divided. The risk of impotence, if the second internal iliac artery is used, is greater than 25% and should be explained to the patient. This represents a very clear statement of currently accepted practice.

Bending and buckling of carbon nanotubes under large strain

The curling of a graphitic sheet to form carbon nanotubes produces a class of materials that seem to have extraordinary electrical and mechanical properties. In particular, the high elastic modulus of the graphite sheets means that the nanotubes might be stiffer and stronger than any other known material, with beneficial consequences for their application in composite bulk materials and as individual elements of nanometre-scale devices and sensors. The mechanical properties are predicted to be sensitive to details of their structure and to the presence of defects, which means that measurements on individual nanotubes are essential to establish these properties. Here we show that multiwalled carbon nanotubes can be bent repeatedly through large angles using the tip of an atomic force microscope, without undergoing catastrophic failure. We observe a range of responses to this high-strain deformation, which together suggest that nanotubes are remarkably flexible and resilient.

Reexamining the definition and criteria of death

The whole-brain criterion of death was first formally proposed by the "Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death" in a "Special Communication" published in JAMA in 1968. Since then, all states in the United States and many western countries have endorsed this definition of death. The strongest defense of the concept of "brain death" was provided by Bernat, Culver, and Gert in a series of papers published in the early 1980s, emphasizing the important distinctions between the definition and the criteria of death and the tests for death. Careful analysis, however, demonstrates that brain-related criteria of death are inconsistent with traditional concepts of death. Thus, although death is properly understood as a biological phenomenon, "brain death" is a social construct created for utilitarian purposes, primarily to permit organ transplantation. The best definition of death is "the event that separates the process of dying from the process of disintegration" and the proper criterion of death in human beings is "the permanent cessation of the circulation of blood." Nevertheless, because brain-related criteria of death have been widely accepted, and because our society has demonstrated a strong commitment to organ transplantation, abandoning the concept of brain death would create serious political problems. Abandoning the "dead donor rule" would solve the problem of obtaining organs for transplantation, but would create different, equally serious, political problems. Preserving the concept of brain death as a social construct, as a "legal definition of death," but distinct from biological death, is also problematic, but may be our most acceptable alternative.

The persistent vegetative state and anencephaly: problematic paradigms for discussing futility and rationing

Medical futility has been a controversial issue for the last several years. Although anencephalic infants and patients in the persistent vegetative state (PVS) have often been suggested as paradigmatic cases for discussing the issue of medical futility, there is no consensus among physicians or ethicists that treatment of such patients is futile and courts have not supported the futility argument. Focusing on the issue of medical futility will not resolve the management issues surrounding the care of patients in PVS or anencephalic infants. Instead, an analysis of the benefits and burdens of treatments offers a potential solution by demonstrating that the real problem is the dissociation of the benefits and burdens of treatment for such patients. We propose the idea that anencephalic infants and patients in PVS provide an appropriate paradigm for discussing the issue of rationing of health-care resources.

Cranial sinus thrombosis and preeclampsia

Cranial sinus thrombosis (CST) is known to be associated with pregnancy and puerperium. A literature review of patients with CST showed a significant proportion of preeclamptic women. The relationship between nephrotic syndrome and hypercoagulability has been well established. We present a 23-year-old gravida III, para I woman with preeclampsia who developed CST. Proteinuria may have played an important pathogenetic role in this setting.

Decreased lysosomal storage in the adult MPS VII mouse brain in the vicinity of grafts of retroviral vector-corrected fibroblasts secreting high levels of beta-glucuronidase

A deficiency of beta-glucuronidase (GUSB) causes the multisystem progressive degenerative syndrome, mucopolysaccharidosis (MPS) type VII (Sly disease), which includes mental retardation. Animal homologues of MPS VII (ref. 3, 4) are models for testing somatic gene transfer approaches to treat the central nervous system in this and other lysosomal storage disorders. Previous attempts to correct murine MPS VII by gene therapy have successfully treated lesions in some organs but not in the brain. Other experimental modalities have forestalled some disease progression in the brain, but only if done at birth, before the onset of severe lesions, when the animals are phenotypically normal. We tested whether therapeutic amounts of GUSB could be delivered to the diseased adult brain by transplanting cells engineered to super-secrete the normal enzyme for export to surrounding neural tissues. Lysosomal distention was cleared from neurons and glial cells in the vicinity of the grafts, showing that the secreted enzyme could reach the diseased cells and reverse lesions in the severely diseased brain. The ability to correct established lesions will be important for the treatment of many lysosomal storage diseases affecting the brain, because most patients are not diagnosed until lesions are advanced enough to affect phenotype or developmental milestones in early childhood, and some forms of the diseases do not become apparent until later in life.

Glycosaminoglycan storage in cultured neonatal murine mucopolysaccharidosis type VII neuroglial cells and correction by beta-glucuronidase gene transfer

The inherited deficiency of beta-glucuronidase activity causes the lysosomal storage disorder mucopolysaccharidosis (MPS) type VII (Sly disease). The sequential catabolism of glycosaminoglycans in lysosomes is blocked, and undegraded substrates accumulate in cells of many tissues, including neurons and glia in the brain. To evaluate the deficient metabolic pathway, primary cultures of mixed brain cells were established from newborn MPS VII mice. beta-Glucuronidase levels and glycosaminoglycan accumulation were studied in normal, carrier, and MPS VII cells. Retroviral vector-mediated transfer of a normal beta-glucuronidase cDNA corrected the enzymatic deficiency in MPS VII cells and restored glycosaminoglycan catabolism to normal. High levels of beta-glucuronidase expression were sustained in vector-corrected nondividing glial cell cultures for >2 months. These studies provide an in vitro model for evaluating somatic gene transfer in neural cells affected in mucopolysaccharidoses.

Manipulation of individual viruses: friction and mechanical properties

We present our results on the manipulation of individual viruses using an advanced interface for atomic force microscopes (AFMs). We show that the viruses can be dissected, rotated, and translated with great facility. We interpret the behavior of tobacco mosaic virus with a mechanical model that makes explicit the competition between sample-substrate lateral friction and the flexural rigidity of the manipulated object. The manipulation behavior of tobacco mosaic virus on graphite is shown to be consistent with values of lateral friction observed on similar interfaces and the flexural rigidity expected for macromolecular assemblies. The ability to manipulate individual samples broadens the scope of possible studies by providing a means for positioning samples at specific binding sites or predefined measuring devices. The mechanical model provides a framework for interpreting quantitative measurements of virus binding and mechanical properties and for understanding the constraints on the successful, nondestructive AFM manipulation of delicate samples.

Penicillin G-induced microbicidal activity of endothelial cells cultured on gelfoam blocks

A body of evidence has surfaced documenting the ability of endothelial cells cultured on monolayers to phagocytose but not kill bacteria. Several years ago, a new three-dimensional endothelial cell culturing model was developed, which simulated the morphology of the endothelium in small vessels and capillaries. Given that endothelial cells may be derived from the same pluripotent stem cells as macrophages, the question of whether endothelial cells might phagocytose and kill bacteria was explored. Endothelial cells grown on Gelfoam blocks exhibited bactericidal activity towards Staphylococcus aureus, reaching maximal killing of > 90% after 2 h. Evidence documents the involvement of bacterial adherence to the plasma membrane of the endothelial cell. This is followed by phagocytosis of S. aureus, leading to intracellular killing. Penicillin G, included in the endothelial cell growth medium, was found to be a critical factor in the bactericidal activity demonstrated by Gelfoam blocks laden with endothelial cells.

A diagnostic algorithm for distinguishing the eosinophilia-myalgia syndrome from fibromyalgia and chronic myofascial pain

OBJECTIVE

To develop a diagnostic algorithm for the eosinophilia-myalgia syndrome (EMS) that complements the existing case definition.

METHODS

We conducted a retrospective study using data on 59 clinical and laboratory variables from a consecutive referral cohort of 91 patients with EMS meeting the Centers for Disease Control and Prevention case definition. Age and sex matched controls included 93 patients with fibromyalgia and 99 patients with chronic myofascial pain. The study period was March 1989 to April 1992. Recursive partitioning was used to create a diagnostic algorithm.

RESULTS

In the 283 case patients and controls with disabling myalgias, 4 differentiating variables identified patients with EMS: extremity edema, leukocyte count > 12.5 x 10(9)/l, dyspnea, and absence of arthralgias. These 4 variables form a diagnostic algorithm that has a sensitivity of 95.6%, a specificity of 96.9%, and positive and negative predictive values of 93.5 and 97.9%, respectively.

CONCLUSION

This algorithm is practical and can be easily applied in any medical setting. It also readily distinguishes EMS from other common myalgia syndromes.

Physicians' attitudes about the care of patients in the persistent vegetative state: a national survey

OBJECTIVE

To study the attitudes and beliefs of physicians who have experience caring for patients in the persistent vegetative state (PVS).

DESIGN

Mailed questionnaire survey.

PARTICIPANTS

500 physicians, 250 from the American Academy of Neurology and 250 from the American Medical Directors Association.

MEASUREMENTS

Physicians' beliefs about diagnosis of the PVS, patient awareness and suffering, treatment withdrawal, appropriate use of health maintenance and life-prolonging therapies, organ donation, lethal injection, and the treatment they would want if they were in the PVS.

RESULTS

68% of surveyed neurologists and 60% of medical directors responded. Thirteen percent of responders believe that patients in the PVS have awareness and experience hunger and thirst; 30% believe they experience pain. Fewer than 9% believe that respiratory failure, cardiogenic shock, acute renal failure, or cancer should be aggressively treated. Eighty-nine percent believe that it is ethical to withdraw artificial hydration and nutrition. Almost two thirds of responders believe that it would be ethical to use the vital organs of patients in the PVS for transplantation, and 20% believe that it would be ethical to hasten the patient's death by lethal injection.

CONCLUSIONS

When evaluating the appropriateness of treatments for patients in the PVS, neurologists and medical directors largely concur. Most physicians in both groups believe that patients in the PVS would be better off dead; that it is not necessary to provide aggressive therapeutic interventions; and that all therapeutic interventions, including artificial nutrition and hydration, can be withheld in certain circumstances. The areas of consensus are remarkable and suggest that an ethical standard that physicians believe should be followed when caring for these patients may be emerging.

Flow cytometric crossmatching in renal transplantation--outcome after five years

The association of a positive flow cytometric crossmatch between recipient IgG directed against donor T lymphocytes and poor outcome is well described in renal transplantation. Until now, no long-term follow-up on such patients has been available. A total of 117 renal transplant patients were followed up for a period of 5 years. Of these, 21 were known to have donor T cell-directed IgG and 5 had B lymphocyte-directed IgG. Both groups of patients with these antibodies had a significantly poorer outcome at 5 years than did the group of patients without IgG (P < 0.0001 Handel Maenzel test). Patients with antibody detected preoperatively were tested again, either at the time of graft failure or at 5 years posttransplantation. The sera were tested against stored donor cells and the intensity of surface IgG compared with the preoperative levels. In those recipients who lost their grafts, the levels increased in 60% of cases but those that retained their grafts also had an increase in levels of donor-directed antibody in 50% of cases. The changing levels of antibody therefore appeared to have little relevance to outcome. However, when IgG isotypes were considered, for those who experienced graft failure and also had a gamma 3 isotype, a rise in IgG was demonstrated in all cases. Conversely, successful grafts with gamma 3 had a decline in levels between preoperative and 5-year samples in three of the four cases (p not significant).

Flow cytometric crossmatching in renal transplantation--the long-term outcome

The association of a positive flow cytometric crossmatch between recipient IgG directed against donor T lymphocytes and poor outcome is well described in renal transplantation. Until now no long-term follow-up on such patients has been available. In this study, 117 renal transplant patients were followed up for a period of 5 years. Of these 21 were known to have donor T cell directed IgG and five had B lymphocyte directed IgG. Both groups of patients with these antibodies had a significantly poorer outcome at 5 years than did the group of patients without IgG (p < 0.0001, Handel Maenzel test). Patients with antibody detected preoperatively were tested again either at the time of graft failure or at 5 years post-transplantation. The sera were tested against stored donor cells and the intensity of surface IgG compared with the preoperative levels. In those recipients who lost their grafts the levels increased in 60% of cases, but those who retained their grafts also had an increase in levels of donor directed antibody in 50% of cases. The changing levels of antibody therefore appeared to have little relevance to outcome. However when IgG isotypes were considered, in those who experienced graft failure and also had a gamma 3 isotype, a rise in IgG was demonstrated in all cases. Conversely, successful grafts with gamma 3 had a decline in levels between preoperative and 5-year samples in three of the four cases (not significant).

The clinical significance of post-transplantation non-HLA antibodies in renal transplantation

This study was undertaken to examine the clinical relevance of antibodies detected in the sera of patients following renal transplantation. The sera from 23 transplant recipients with acute rejection and 10 transplant recipients with diagnosed chronic rejection were tested against various epithelial, monocyte and endothelial cell lines (A549, HTB44, primary renal epithelial, U937 and Ea-hy 926). The test used for detecting binding antibodies was a simple, indirect immunofluorescence flow cytometric technique. The level of IgG antibodies directed against the test cell lines was examined in the sera of patients with mild or severe rejection and compared to those of patients showing no signs of rejection. Patients with chronic rejection were found to have increased levels of antibodies (IgG and IgM) when compared to patients with either end-stage renal failure or patients with stable post-transplant renal function. Antibodies detected by the present technique were directed against antigens found on all cell lines tested, and immunoblotting indicated that they were directed against non-HLA antigens. In conclusion, monitoring for the presence of such antibodies may provide a valuable prognostic indicator of graft rejection in renal transplant patients.

Neural progenitor cell engraftment corrects lysosomal storage throughout the MPS VII mouse brain

Many metabolic diseases affecting the central nervous system are refractory to treatment because the blood-brain barrier restricts entry of therapeutic molecules. It may be possible to deliver therapeutic gene products directly to the brain by transplantation of neural progenitor cells, which can integrate into the murine central nervous system in a cytoarchitecturally appropriate manner. We tested this approach in mucopolysaccharidosis VII (Sly disease), a lysosomal storage disorder of humans, dogs and mice caused by an inherited deficiency of beta-glucuronidase. Lysosomal accumulation of glycosaminoglycans occurs in the brain and other tissues, causing a fatal progressive degenerative disorder, including mental retardation. Treatments are designed to provide a source of normal enzyme for uptake by diseased cells. We report here that by transplanting beta-glucuronidase-expressing neural progenitors into the cerebral ventricles of newborn mice, donor cells engrafted throughout the neuraxis. At maturity, donor-derived cells were present as normal constituents of diverse brain regions. beta-Glucuronidase activity was expressed along the entire neuraxis, resulting in widespread correction of lysosomal storage in neurons and glia in affected mice.

The value of posttransplant monitoring of interleukin (IL)-2, IL-3, IL-4, IL-6, IL-8, and soluble CD23 in the plasma of renal allograft recipients

Over the past few years, the central role of cytokines in the amplification of the immune response has been reported and several studies have examined the relationship between the plasma level of individual lymphokines during renal allograft rejection. The aim of the present investigation was to study simultaneously IL-2, IL-3, IL-4, IL-6, IL-8, and soluble CD23. Analysis of results has allowed both the prognostic value and any possible interrelationships between the measured cytokines to be determined. We studied 16 renal transplant recipients for the first 14 days after transplantation. Seven patients showed clinical evidence of acute allograft rejection and 5 showed excellent stable graft function with no signs of rejection. Primary nonfunction was seen in 4 patients. The plasma levels of each cytokine were measured by commercially available ELISA and immunoradiometric assay kits. As reported in previous studies, plasma IL-2 levels, whenever found at detectable levels, were predictive of impending graft rejection. Serial monitoring of IL-4 and IL-6 was more reliable for the differential diagnosis of rejection, particularly toward the end of the first week after transplantation. IL-3, IL-8, and soluble CD23 were not diagnostic or predictive of rejection, due to the occurrence of significantly high levels in transplant patients who showed no evidence of clinical rejection. While the value of cytokine monitoring has been shown in this study, it should be remembered that infection, although not seen in these studies, may have a profound affect on the results obtained.

Progression of hormone-dependent adenocarcinoma cells to hormone-independent spindle carcinoma cells in vitro in a clonal spontaneous rat mammary tumor cell line

A hormone-dependent, clonal carcinoma cell line, designated RM22-F5, was derived from a malignant mammary mixed tumor spontaneously arising in an outbred old female Wistar rat. These cells expressed keratin and desmosomal protein and formed epithelial monolayers in a growth factor and hormone-supplemented medium (LHC-8) containing 10% fetal bovine serum (E-type cells). Cells subcultured for 6 to 8 passages in RPMI 1640 medium containing 10% fetal bovine serum without supplements appeared to be fibroblastic and expressed vimentin (F-type cells). The shift to a fibroblast-like morphology was associated with a more malignant phenotype which included rapid, hormone-independent growth and invasive sarcoma-like character in nude mice. F-type cells were no longer able to express their original epithelial phenotype in LHC-8 medium. Cytogenetic analysis revealed that both E- and F-type cells had essentially the same karyotype. Analysis of PCR-amplified DNA further demonstrated a point mutation of the H-ras-1 gene at codon 12 and loss of the normal H-ras-1 allele in both cell types. Genetic tagging of E-type cells with the neomycin-resistance gene resulted in the generation of F-type cells with neomycin resistance in RPMI 1640 medium, suggesting that F-type cells are a malignant variant of E-type cells arising during in vitro culture. Somatic cell fusion between E- and F-type cells revealed that with most hybrid clones tested, the fibroblast-like phenotype was greatly suppressed. These results suggest that an irreversible phenotypic transition, representative of tumor progression from hormone-dependent adenocarcinoma to more malignant hormone-independent spindle carcinoma cells, is a recessive event and may involve loss of a suppressor function.