Diagnostic strategies in CADASIL

BACKGROUND

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited autosomal dominant condition characterized by migraine, recurrent stroke, and dementia. It results from mutations in the notch3 gene but mutations may occur at multiple sites making molecular diagnosis time consuming. It has been suggested that the presence of granular osmiophilic material (GOM) on skin biopsy and involvement of the anterior temporal lobe and external capsule on MRI may help in diagnosis.

METHODS

The authors identified 83 potential index cases from the British population and screened exons 2 to 23 of notch3. MRI scans were scored using a modified Scheltens scale. Skin biopsy was performed in a subgroup.

RESULTS

Fifteen different point mutations were identified in 48 families, 73% of which were in exon 4, 8% in exon 3, and 6% in each of exons 5 and 6. Moderate or severe involvement of the anterior temporal pole on MRI had a sensitivity of 89% and specificity of 86% for diagnosis of CADASIL, whereas external capsule involvement had a high sensitivity of 93% but a low specificity of 45%. Skin biopsy, performed in 18 cases, had a sensitivity of 45% and specificity of 100%.

CONCLUSIONS

The spectrum of mutations in this study can be used to plan appropriate screening protocols; a suggested protocol is to screen exon 4, and proceed to exons 3, 5, and 6 where indicated. GOM on skin biopsy is diagnostic but can be negative. Anterior temporal pole involvement on MRI is a useful diagnostic marker.

Melanoma chondroitin sulfate proteoglycan regulates matrix metalloproteinase-dependent human melanoma invasion into type I collagen

Tumor cell adhesion and proteolysis of the extracellular matrix proteins surrounding the cells are tightly linked processes in tumor invasion. In this study, we sought to identify components of the cell surface of a vertical growth phase melanoma cell line, WM1341D, that mediate invasive cellular behavior. We determined by antisense inhibition that melanoma chondroitin sulfate proteoglycan (MCSP) and membrane-type 3 matrix metalloproteinase (MT3-MMP) expressed on WM1341D are required for invasion of type I collagen and degradation of type I gelatin. MT3-MMP co-immunoprecipitated with MCSP in WM1341D melanoma cells cultured on type I collagen or laminin. The association between MT3-MMP and MCSP was largely disrupted by removing chondroitin sulfate glycosaminoglycan (CS) from the cell surface, suggesting CS could mediate the association between the two cell surface core proteins. Recombinant MT3-MMP and MT3-MMP from whole cell lysates of WM1341D cells were specifically eluted from CS- conjugated affinity columns. The results indicate that MT3-MMP possesses the potential to promote melanoma invasion and proteolysis and that the formation of a complex between MT3-MMP and MCSP may be a crucial step in activating these processes.

Hyaluronan synthase elevation in metastatic prostate carcinoma cells correlates with hyaluronan surface retention, a prerequisite for rapid adhesion to bone marrow endothelial cells

Bone marrow is the primary site of metastasis in patients with advanced stage prostate cancer. Prostate carcinoma cells metastasizing to bone must initially adhere to endothelial cells in the bone marrow sinusoids. In this report, we have modeled that interaction in vitro using two bone marrow endothelial cell (BMEC) lines and four prostate adenocarcinoma cell lines to investigate the adhesion mechanism. Highly metastatic PC3 and PC3M-LN4 cells were found to adhere rapidly and specifically (70-90%) to BMEC-1 and trHBMEC bone marrow endothelial cells, but not to human umbilical vein endothelial cells (15-25%). Specific adhesion to BMEC-1 and trHBMEC was dependent upon the presence of a hyaluronan (HA) pericellular matrix assembled on the prostate carcinoma cells. DU145 and LNCaP cells were only weakly adherent and retained no cell surface HA. Maximal BMEC adhesion and HA encapsulation were associated with high levels of HA synthesis by the prostate carcinoma cells. Up-regulation of HA synthase isoforms Has2 and Has3 relative to levels expressed by normal prostate corresponded to elevated HA synthesis and avid BMEC adhesion. These results support a model in which tumor cells with up-regulated HA synthase expression assemble a cell surface hyaluronan matrix that promotes adhesion to bone marrow endothelial cells. This interaction could contribute to preferential bone metastasis by prostate carcinoma cells.

GATA zinc finger interactions modulate DNA binding and transactivation

GATA-1 and other vertebrate GATA factors contain a DNA binding domain composed of two adjacent homologous zinc fingers. Whereas only the C-terminal finger of GATA-1 is capable of independent binding to the GATA recognition sequence, double GATA sites that require both fingers for high affinity interaction are found in several genes. We propose a mechanism whereby adjacent zinc fingers interact to influence the binding and transactivation properties of GATA-1 at a subset of DNA-binding sites. By using two such double GATA sites we demonstrate that the N-terminal finger and adjacent linker region can alter the binding specificity of the C-terminal finger sufficiently to prevent it from recognizing some consensus GATA sequences. Therefore, the two zinc fingers form a composite binding domain having a different DNA binding specificity from that shown by the constituent single C-terminal finger. Furthermore, we compare two of these double sites and show that high affinity binding of GATA-1 to a reporter gene does not necessarily induce transactivation, namely the sequence of the DNA-binding site can alter the ability of GATA-1 to stimulate transcription.

The abilities of children with mental retardation to remember personal experiences: implications for testimony

Investigated the abilities of children with mental retardation to remember the details of a personally experienced event. A simulated health check was administered to 20 children with mental retardation and 40 normally developing children, half matched on mental age (MA) and half matched on chronological age (CA) with the children with mental retardation. The children's memory was assessed immediately after the health check and 6 weeks later. Overall, the children with mental retardation accurately recalled the health check features, provided detail, and resisted misleading questions about features that did not occur. The group with mental retardation performed similarly to the MA matches on virtually all of the memory variables. The children with mental retardation performed worse than the CA matches on most of the memory variables, although they were able to recall a similar number of features. The findings are discussed in terms of the ability of children with mental retardation to provide accurate testimony.

Melanoma chondroitin sulphate proteoglycan regulates cell spreading through Cdc42, Ack-1 and p130cas

Melanoma chondroitin sulphate proteoglycan (MCSP) is a cell-surface antigen that has been implicated in the growth and invasion of melanoma tumours. Although this antigen is expressed early in melanoma progression, its biological function is unknown. MCSP can stimulate the integrin-alpha4 beta1-mediated adhesion and spreading of melanoma cells. Here we show that stimulated MCSP recruits tyrosine-phosphorylated p130 cas, an adaptor protein important in tumour cell motility and invasion. MCSP stimulation also results in a pronounced activation and recruitment of the Rho-family GTPase Cdc42. MCSP-induced spreading of melanoma cells is dependent upon active Cdc42, a Cdc42-associated tyrosine kinase (Ack-1) and tyrosine phosphorylation of p130cas. Furthermore, vectors inhibiting Ack-1 or Cdc42 expression and/or function abrogate MCSP-induced tyrosine phosphorylation and recruitment of p130cas. Our findings indicate that MCSP may modify tumour growth or invasion by a unique signal-transduction pathway that links Cdc42 activation to downstream tyrosine phosphorylation and subsequent cytoskeletal reorganization.

Targeted disruption of the adipocyte lipid-binding protein (aP2 protein) gene impairs fat cell lipolysis and increases cellular fatty acid levels

The availability of mice containing an adipocyte lipid-binding protein (ALBP/aP2) gene disruption allowed for a direct examination of the presumed role of lipid-binding proteins in the mobilization and trafficking of intracellular fatty acids. Total body and epididymal fat pad weights, as well as adipose cell morphology, were unaltered in male ALBP/aP2 disrupted mice when compared to their wild-type littermates. Analysis of adipocytes isolated from wild-type and ALBP/aP2 null mice revealed that a selective 40- and 13-fold increase in the level of the keratinocyte lipid-binding protein (KLBP) mRNA and protein, respectively, accompanied the ALBP/aP2 gene disruption. Although KLBP protein was significantly up-regulated, the total lipid-binding protein level decreased 8 -fold as a consequence of the disruption. There was no appreciable difference in the rate of fatty acid influx or esterification in adipocytes of wild-type and ALBP/aP2 null animals. To the contrary, basal lipolysis decreased approximately 40% in ALBP/aP2 nulls as compared to wild-type littermates. The glycerol release from isproterenol-stimulated ALBP/aP2 null fat cells was similarly reduced by approximately 35%. Consistent with a decrease in basal efflux, the non-esterified fatty acid (NEFA) level was nearly 3-fold greater in adipocytes from ALBP/aP2 nulls as compared to wild-type animals. The significant decrease in both basal and isoproterenol-stimulated lipolysis in adipose tissue of ALBP/aP2 null mice supports the model whereby intracellular lipid-binding proteins function as lipid chaperones, facilitating the movement of fatty acids out of the fat cell.

Biochemical and biophysical analysis of the intracellular lipid binding proteins of adipocytes

Adipocytes express two lipid-binding proteins; the major one termed the adipocyte lipid-binding protein or aP2 (ALBP/aP2) and a minor one referred to as the keratinocyte lipid-binding protein (KLBP). In order to evaluate the potential physiological roles for these proteins, their biochemical and biophysical properties have been analyzed and compared. ALBP/aP2 and KLBP exhibit similar binding affinities for most long-chain fatty acids; however, ALBP/aP2 exhibits a two to three-fold increased affinity for myristic, palmitic, oleic and linoleic acids, the predominant fatty acids of adipocytes. As measured by guanidinium hydrochloride denaturation, the stability of ALBP/aP2 is nearly 3 kcal/mol greater than that of KLBP. While the pI of ALBP/aP2 was determined to be 9.0, that of KLBP is 6.5 suggesting differing net charges at physiological pH. Analysis of surface electrostatic properties of ALBP/aP2 and KLBP revealed similar charge polarity, although differences in the detailed charge distribution exist between the proteins. The distribution of hydrophobic patches was also different between the proteins,ALBP/aP2 has only scattered hydrophobic surfaces while KLBP has a large hydrophobic patch near the ligand portal into the binding cavity. In sum, these results point out that despite the striking similarity between ALBP/aP2 and KLBP in tertiary structure, significant differences in ligand binding and surface properties exist between the two proteins. Hence, while it is tempting to speculate that ALBP/aP2 and KLBP are metabolically interchangeable, careful analysis suggests that the two proteins are quite distinct and likely to play unique metabolic roles.

Analysis of a series of phenylalanine 57 mutants of the adipocyte lipid-binding protein

The importance of phenylalanine 57, an adipocyte lipid-binding protein (ALBP) portal residue, to ligand affinity and specificity has been investigated using a series of ALBP position 57 mutants. In wild-type ALBP, phenylalanine 57 undergoes a side chain rotation upon ligand binding, moving from an inwardly oriented, ligand-exclusive position in apoprotein structures to an outwardly oriented position in the holoprotein. To examine the role of F57 side chain rotation in the apoprotein-holoprotein transition and in ligand selectivity, ALBP site-specific mutants F57A, F57G, F57H, and F57W were expressed in Escherichia coli and purified to homogeneity. Mutants were analyzed for binding characteristics and stability toward chemical denaturation, and energy-minimized models of each mutant were constructed using apo, oleate-, and arachidonate-bound ALBP crystallographic coordinates. The stability of ALBP forms (wtALBP approximately F57G > F57A > F57W > F57H) was unrelated to the affinity of ALBP forms (wtALBP approximately F57W > F57H > F57G > F57A) for various lipids and did not vary between fatty acids. Since ligand selectivity was maintained between wild type and all mutants while ligand affinity was grossly diminished, we conclude that phenylalanine 57 is critical to the formation of the fatty acid/ALBP complex, but is uninvolved in determination of selectivity over the range of physiological ligands tested.

Increased lithium serum and red blood cell concentrations during ketorolac coadministration

Case reports of a lithium-ketorolac drug interaction have been published, but no formal investigation of this interaction has been conducted. The objective of the study presented here was to determine significant changes in lithium serum and red blood cell (RBC) concentrations after lithium and ketorolac (oral formulation) coadministration at steady-state conditions. Five healthy men participated in the study and received lithium 900 mg/day (300 mg in the morning and 600 mg at bedtime) for 13 days. Ketorolac 40 mg/day (10 mg four times a day) was added on days 8 through 12. Ten blood samples were obtained on days 7 and 13 to determine area under the concentration-time curve (AUC) lithium serum and RBC concentrations. Serum and RBC lithium concentrations were assayed by atomic absorption spectrophotometry with an intra-assay coefficient of variation (CV) of 1.2% on day 1 (range 0-1.0 microg/mL) and 4.9% (range 0-1.0 microg/mL) on day 2 and an interassay CV of 2.9% (range 0-1.0 microg/mL) on days 1 and 2 of serum analysis and a CV of 5.3% (range 0-0.3 microg/mL) of RBC concentrations. Total serum AUC lithium and RBC AUC values significantly increased by 24% (p < 0.02) and by 27% (p < 0.05) with the ketorolac coadministration, respectively. An increased incidence and severity of lithium-associated side effects were reported during concomitant administration. A clinically significant drug interaction can occur when ketorolac is added to lithium therapy.

Regulation of gene expression in adipose cells by polyunsaturated fatty acids

In fat cells polyunsaturated fatty acids are both substrates for, and products of, triacylglycerol metabolism. Dietary fatty acids are efficiently incorporated into the triacylglycerol droplet under lipogenic conditions while rapidly mobilizing them during lipolytic stimulation. Hence, the flux and magnitude of the fatty acid pool in adipocytes is constantly changing in response to hormonal, metabolic and genetic determinants. Due to the rapidly changing flux of fatty acids, the majority of genes encoding enzymes and proteins of lipid metabolism are largely refractory to long-term regulatory control by fatty acids. Only at extremes of high or low lipid levels, or under pathophysiological conditions, do adipose genes respond by up- or down-regulating gene expression. Despite the lack of responsiveness to lipids in adipose tissue, a surprisingly large number of genes have been characterized recently as lipid responsive when assayed in heterologous systems. These observations suggest an endogenous negative element exists in the lipid signaling pathway in adipocytes. The major intracellular lipid binding protein in adipose cells is the adipocyte lipid binding protein (ALBP), the product of the aP2 gene. This protein is 15 kDa, abundant and found exclusively in the cytoplasm of adipocytes. The protein binds fatty acids and related lipids in a 1:1 stoichiometry within a large water filled interior cavity. The lipid binding protein forms high affinity associations with polyunsaturated fatty acids such as arachidonic acid (Kd approximately 250 nM) but not with prostaglandins of the E, D or J series (Kd > 4 microM). The upstream region of the aP2 gene contains a peroxisome-proliferator activated receptor response element which associates with PPARs to regulate its expression. A positive autoregulatory circuit exists to upregulate lipid binding protein expression when polyunsaturated fatty acid levels are increased. Analysis of adipose tissue from aP2 null animals generated by a targeted disruption revealed that the partial loss of ALBP expression in heterozygotes and complete lack of ALBP in the nulls was accompanied by a compensatory up-regulation of the keratinocyte lipid binding protein. However, the total amount of lipid binding protein in the nulls was less than 15% that in the wild type littermates. No evidence was found for upregulation of other lipid binding proteins such as the heart FABP or liver FABP. In aP2 nulls, the fatty acid composition was unaltered but the mass of fatty acid per gram tissue more than doubled relative to wild type. In heterozygotes, the level of fatty acid was intermediate to that of wild-type and nulls, consistent with an intermediate level of lipid binding protein. These results indicate that the fatty acid pool level in adipocytes is inversely correlated with the amount of lipid binding protein. Since prostaglandin biosynthesis is dependent upon polyunsaturated fatty acid substrates, the intracellular lipid binding proteins control accessibility of substrates of the prostanoid pathway. Intracellular lipid binding proteins therefore are negative elements in polyunsaturated fatty acid control of gene expression.

Biochemical and crystallographic analyses of a portal mutant of the adipocyte lipid-binding protein

A number of crystallographic studies of the adipocyte lipid-binding protein have established that the fatty acid-binding site is within an internalized water-filled cavity. The same studies have also suggested the existence of a region physically distinct from the fatty acid-binding site which connects the cavity of the protein with the external solvent, hereafter referred to as the portal. In an effort to examine the portal region, we have used site-directed mutagenesis to introduce the mutations V32D/F57H into the murine ALBP cDNA. Mutant protein has been isolated, crystallized, and its stability and binding properties studied by biochemical methods. As assessed by guanidine-HCl denaturation, the mutant form exhibited a slight overall destabilization relative to the wild-type protein under both acid and alkaline conditions. Accessibility to the cavity in both the mutant and wild-type proteins was observed by stopped-flow analysis of the modification of a cavity residue, Cys117, by the sulfhydryl reactive agent 5, 5'-dithiobis(2-nitrobenzoic acid) at pH 8.5. Cys117 of V32D/F57H ALBP was modified 7-fold faster than the wild-type protein. The ligand binding properties of both the V32D/F57H mutant and wild-type proteins were analyzed using a fluorescent probe at pH 6.0 and 8.0. The apparent dissociation constants for 1-anilinonaphthalene-8-sulfonic acid were approximately 9-10-fold greater than the wild-type protein, independent of pH. In addition, there is a 6-fold increase in the Kd for oleic acid for the portal mutant relative to the wild-type at pH 8.0. To study the effect of pH on the double mutant, it was crystallized and analyzed in two distinct space groups at pH 4.5 and 6.4. While in general the differences in the overall main chain conformations are negligible, changes were observed in the crystallographic structures near the site of the mutations. At both pH values, the mutant side chains are positioned somewhat differently than in wild-type protein. To ensure that the mutations had not altered ionic conditions near the binding site, the crystallographic coordinates were used to monitor the electrostatic potentials from the head group site to the positions near the portal region. The differences in the electrostatic potentials were small in all regions, and did not explain the differences in ligand affinity. We present these results within the context of fatty acid binding and suggest lipid association is more complex than that described within a single equilibrium event.

Intracellular lipid-binding proteins and their genes

Intracellular lipid-binding proteins are a family of low-molecular-weight single-chain polypeptides that form 1:1 complexes with fatty acids, retinoids, or other hydrophobic ligands. These proteins are products of a large multigene family of unlinked loci distributed throughout the genome. Each lipid-binding protein exhibits a distinctive pattern of tissue distribution. Transcriptional control, regulated by a combination of peroxisome proliferator activated receptors and CCAAT/enhancer-binding proteins, allows for a variety of both cell and tissue-specific expression patterns. In some cells, fatty acids increase the expression of the lipid-binding protein genes. Fatty acids, or their metabolites, are activators of the peroxisome proliferator-activated receptor family of transcription factors. Therefore, as the concentration of lipid in the diet increases, the expression of lipid-binding proteins coordinately increases. As revealed by X-ray crystallography, the lipid-binding proteins fold into beta-barrels, forming a large internal water-filled cavity. Fatty acid ligands are bound within the cavity, occupying only about one-third of the accessible volume. The bound fatty acid is stabilized via a combination of enthalpic and entropic forces that govern ligand affinity and selectivity. Cytoplasmic lipid-binding proteins are the intracellular receptors for hydrophobic ligands, delivering them to the appropriate site for use as metabolic fuels and regulatory agents.

A multicenter trial of FK506 (tacrolimus) therapy in refractory acute renal allograft rejection. A report of the Tacrolimus Kidney Transplantation Rescue Study Group

A multicenter trial was conducted to evaluate the efficacy and safety of tacrolimus in the treatment of refractory renal allograft rejection. Renal transplant recipients experiencing biopsy-proven recurrent acute allograft rejection were eligible if the current rejection episode was refractory to corticosteroids. A total of 73 patients were enrolled, of whom 59 (81%) had previously received at least one course of antilymphocyte antibody as rejection therapy. One-year follow-up was available in 93% of patients. Median time to tacrolimus rescue therapy was 75 days after transplantation (range, 18-1448 days). Therapeutic responses to tacrolimus included improvement in 78% of patients, stabilization in 11%, and progressive deterioration in 11%. The risk of experiencing progressive deterioration was related to the pretacrolimus serum creatinine level: serum creatinine < or = mg/dl, 3%; 3.1-5 mg/dl, 16% (P < 0.04); > 5 mg/dl, 23% (P < 0.02). Twelve-month (from the time of initiation of tacrolimus therapy) actuarial patient and graft survival rates were 93% and 75%. Graft loss occurred in 19 patients (25%) at a median time of 108 days. Fourteen episodes of recurrent rejection were diagnosed in 10 patients (14%), at a median time of 101 days. Eleven episodes of recurrent rejection were treated (three patients underwent transplant nephrectomy), with resolution achieved in nine patients. Antilymphocyte antibody therapy was not used to treat recurrent rejection. Serum creatinine values improved during tacrolimus therapy: median serum creatinine level before tacrolimus, 3.2 mg/dl; median at 1 year after tacrolimus, 1.8 mg/dl. Twelve infections were documented in 11 patients (15%), including cytomegalovirus infection in three patients (4%). Posttransplant lymphoproliferative disorder was diagnosed in a single patient. Tacrolimus whole blood levels averaged 15.0 +/- 9.9 ng/ml at day 7 of tacrolimus therapy and 9.4 +/- 5.1 ng/ml at 1 year, and were consistent among individual centers. Treatment outcome did not correlate with tacrolimus blood levels. The most commonly observed adverse events were neurological and gastrointestinal. Seventy-four percent of patients received tacrolimus for at least 1 year. Tacrolimus therapy was discontinued in 18% of patients for rejection (11% for progressive, unrelenting rejection, and 7% for recurrent rejection). Tacrolimus therapy was discontinued in 8% of patients due to adverse events. In conclusion, tacrolimus rescue therapy provides (1) prompt, effective reversal of refractory renal allograft rejection, (2) good long-term renal allograft function, (3) a low incidence of recurrent rejection, and (4) an acceptable safety profile in renal allograft recipients experiencing refractory rejection.

Studying the impact of women on osteopathic physician workforce predictions

Women have been entering the physician workforce in ever-increasing numbers since the 1970s, and women are expected to reach numeric parity with men early in the next century. In an effort to predict changes in the physician workforce, analysts have relied primarily on data collected in the allopathic medical profession. Documented differences in practice characteristics between osteopathic and allopathic physicians make current workforce projections--based heavily on assumptions rooted in the allopathic medical profession--nonrepresentative of the osteopathic medical profession. The authors attempt to identify the impact of increasing numbers of women physicians on the osteopathic medical profession. They trace the historical presence of women in medicine and explore speculations concerning the continued growth in the numbers and percentage of women in medicine. The authors analyze data from the 1992 AOA census in search of identifiable trends in practice location and specialty choice based on gender, marital status, and dual-osteopathic physician couples. Finally, they discuss the need for complete and accurate data collection for the profession as data-driven workforce policy decisions ultimately affect the entire profession.

Cyclosporine bioavailability: dosing implications and impact on clinical outcomes in select transplantation subpopulations

Reports in the literature indicate that clinical outcomes in select patient subpopulations have been inferior to those in the general transplantation population. Of potential interest in this regard is the finding that lower cyclosporine bioavailability correlates with a higher incidence of acute rejection and graft loss. To gain insights into these issues, we examined data from renal transplant recipients at our own centers and in one large data base. Our experience revealed that cyclosporine bioavailability was markedly lower in patients who developed acute or chronic rejection than in those with stable graft function. An analysis by demographic or clinical factors showed that cyclosporine bioavailability was lower in diabetics and black patients. In one study, diabetics required much higher daily doses of cyclosporine to achieve outcomes comparable to those in non-diabetics; even then, diabetics attained lower cyclosporine blood levels. Other work found that long-term graft survival rates were poorer in blacks, even though cyclosporine dosages and blood levels were comparable to those in whites. A case-controlled study from the pregnancy registry found that cyclosporine dosages were consistently higher in pregnant patients who maintained good graft function than in those who experienced graft dysfunction. These results suggest that the subpopulations examined should receive immunosuppression with higher cyclosporine dosages than those used in the general transplantation population. These subpopulations may also benefit from a cyclosporine formulation that provides better absorption, resulting in more consistent and predictable cyclosporine bioavailability.

Kidney transplantation in diabetic patients using cyclosporine. Five-year follow-up

OBJECTIVE

To review our center's experience with kidney transplantation in diabetic recipients; specifically, to compare long-term (5-year) patient and graft survival rates between diabetic and nondiabetic recipients overall and according to donor source using cyclosporine-based immunosuppression.

DESIGN

A retrospective review of all kidney transplants performed over the 7-year period from 1987 to 1993.

SETTING

A large urban tertiary care referral center with a long history of kidney transplantation and care of the diabetic patient.

PATIENTS

All patients receiving a kidney transplant, either alone or simultaneously with a pancreas transplant, were reviewed.

MAIN OUTCOME MEASURES

Actuarial patient and graft survival, serum creatinine levels, and causes of late graft loss.

RESULTS

There was no significant difference in actuarial 5-year patient or kidney graft survival between diabetic and nondiabetic recipients overall or when analyzed by donor source. There was no significant difference in mean serum creatinine levels at 5 years between diabetic and nondiabetic recipients overall or between diabetic and nondiabetic cadaveric recipients. While chronic rejection was the major cause of late graft loss in nondiabetic recipients, death with a functioning graft, principally due to cardiovascular disease, was the major cause of graft loss in diabetic recipients.

CONCLUSIONS

With cyclosporine-based immunosuppression, diabetic kidney transplant recipients have 5-year patient and graft survival rates and allograft function comparable to nondiabetic recipients. Given the high mortality of diabetic patients receiving dialysis, kidney transplantation is the treatment of choice for end-stage diabetic renal disease.

A comparison of operation, endoscopic retrograde cholangiopancreatography, and percutaneous transhepatic cholangiography in biliary complications after hepatic transplantation

BACKGROUND

Biliary complications (BC) remain a significant cause of morbidity and mortality after orthotopic liver transplantation (OLT).

STUDY DESIGN

In an effort to determine the incidence of BC after OLT and the success of management options, 157 hepatic transplants performed from January 1987 to July 1991 were reviewed.

RESULTS

The incidence of BC was 25 percent, with a one year mortality rate of 43.5 percent compared with 23.4 percent for patients in a control group (p < 0.05). Most BC occurring before postoperative day 30 presented as leaks, with a one year mortality rate of 50 percent (p < 0.03 versus control group). Biliary complications presenting after postoperative day 30 presented as strictures, with a one year mortality rate of 36.8 percent (p = NS versus control group). Endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiography (PTHC), and operative treatment were analyzed to determine relative patency rates after intervention for BC. The analysis showed that ERCP and PTHC were equivalent, with a one year patency rate of 45 percent. Operative treatment had a patency rate of 89 percent (p < 0.05 compared to ERCP and PTHC).

CONCLUSIONS

The results from ERCP and PTHC may be useful for delineation of rejection versus BC after OLT. However, operative treatment is significantly more effective for definitive treatment of BC after OLT.

Complexity of the healthcare crisis in rural America

Because osteopathic physicians comprise 15.3% of all physicians in small rural counties, while making up only 5.1% of the nation's physicians, the solutions to the healthcare crisis for rural America are of special interest to them. The authors explore the incredible diversity of rural communities and the difficulty with defining the term "rural." They give the background of efforts to address rural health problems and the reasons accessible healthcare--available, acceptable and affordable--has been so elusive in rural settings. The authors also explain the relative success of the osteopathic medical profession and address the role osteopathic physicians can play in the future. Finally, they explore the exciting new possibilities that telemedicine offers.

Prevention of graft-versus-host disease following small bowel transplantation with polyclonal and monoclonal antilymphocyte serum. The effect of timing and route of administration

Graft-versus-host disease is a potential problem following small bowel transplantation. We have previously shown that a two-day intraperitoneal course of polyclonal antilymphocyte serum completely prevents GVHD without impairing allograft function in a unidirectional rat small bowel transplant model. In the present study we sought to determine the optimum route and timing of ALS administration and whether donor pretreatment with the anti-T cell receptor monoclonal antibody R73 would be similarly effective in preventing GVHD. Both intravenous and intraperitoneal injection of ALS effectively prevent GVHD in this model. ALS must be given to donors at least 48 hr prior to graft procurement for maximum effectiveness. Prevention of GVHD correlates with lymphocyte depletion in mesenteric lymph nodes, as opposed to peripheral blood or small bowel lamina propria. Donor pretreatment with the monoclonal antibody R73 significantly delays the onset of GVHD in this small bowel transplant model but appears less effective than polyclonal ALS.

Immunologic heterogeneity among potential transplant recipients. Prospects for predicting immune responses to allografts with in vitro tests

The ability to accurately predict the response of a specific patient to a specific organ allograft has long been a goal of organ transplantation. The role of histocompatibility antigens in determining the acceptance or rejection of an allograft-recipient combination has been thoroughly investigated, but is being reevaluated as improved immunosuppressive agents become available. Early efforts at immunologic monitoring are reviewed in addition to more recent efforts that focus on the cellular and molecular mediators of immunity. The authors' own experience with lymphokine measurements in clinical transplantation is also reviewed, with emphasis on the role of interleukin-2 (IL-2) and its soluble receptor (IL-2R) in various transplant-associated conditions. The authors conclude that information useful in the management of transplant patients may be derived from serial measurements of IL-2 and IL-2R, but that infections, especially CMV, may not be ruled out with certainty by these measurements alone. The available data suggest that study of additional lymphokines such as interferon-gamma (IFN-gamma) and tumor necrosis factor (TNF) may be useful in discriminating rejection from infections in transplant patients.

Sequential interleukin 2 and interleukin 2 receptor levels distinguish rejection from cyclosporine toxicity in liver allograft recipients

Previous studies of renal transplant recipients have demonstrated that allograft rejection is accompanied by an increase in plasma and urinary levels of interleukin 2 and its soluble receptor before the development of clinical symptoms. After measuring interleukin 2 and interleukin 2 receptor levels in the plasma, bile, and urine of liver transplant recipients, we found that rejection is preceded by elevation of plasma and biliary levels of both substances, that cyclosporine toxicity did not affect either of these levels, and that urinary levels of the substances are unaffected in either condition. Levels of interleukin 2 and interleukin 2 receptors increased in bile earlier than in plasma, and interleukin 2 levels did not overlap among stable patients and those experiencing rejection, whereas levels of interleukin 2 receptors did. Serial measurements of interleukin 2 levels, particularly in the product of the transplanted organ, provide a reliable assessment of the immunologic status of the allograft.

Sequential determinations of urinary cytology and plasma and urinary lymphokines in the management of renal allograft recipients

Urine cytology, plasma (P), and urinary (U) interleukin-2 (IL-2)* and IL-2 receptor (IL-2R) levels were evaluated as immunological monitoring techniques in 65 renal allograft recipients. Normal individuals showed normal urine cytology, IL-2(U) = 0, IL-2(P) = 0.4 +/- 0.1 ng/ml (mean +/- SEM) and IL-2R(P) = 318 +/- 26 U/ml. Stable transplants also showed normal urine cytology, no IL-2(U), IL-2(P) = 0.8 +/- 0.2 ng/ml, and IL-2R(P) = 326 +/- 29 U/ml. Rejection episodes (n = 21) were accompanied by cytologic changes, including lymphocyturia, exfoliation of immature tubular cells, platelet aggregates, and fibrin deposits. The corresponding lymphokine changes were IL-2(U) = 39.6 +/- 1.4 ng/ml, IL-2(P) = 79 +/- 21 ng/ml, and IL-2R = 1884 +/- 202 U/ml, all markedly increased. Successful treatment was associated with return of all parameters to normal; treatment failure was associated with continued abnormalities. Fourteen rejections unresponsive to Solumedrol (500 mg x 5 days) required OKT3 rescue (5 mg x 14 days). In the 11 that were reversed, onset of OKT3 therapy was characterized by markedly increased exfoliation of necrotic cellular debris, lymphocytes, and collecting duct cells. Interestingly, serum creatinine increases of 57.2 +/- 18.9% (range 25-90%) over pre-OKT3 levels were noted. Maximal changes occurred 48-72 hr after the first dose, followed by gradual return to normal. Rejections unresponsive to OKT3 (n = 3) showed no cytologic changes from the pretreatment mean creatinine increase of 13.2 +/- 2.7% (range 9-15%), and maximum change occurred 24 hr after the first dose. Rejections responsive to Solumedrol only (n = 4) showed gradual improvement of all parameters. Rejections treated with Solumedrol following failed OKT3 prophylaxis (n = 3) did not reverse and continued to show rejection associated cytologic changes and abnormal creatinines. Patients experiencing CsA toxicity (n = 12) showed mild creatinine elevations, normal or negative IL-2(P) and IL-2R(P) levels, and no IL-2(U). They showed distinctive cytologic changes consisting of swollen convoluted tubular cells with nuclear pyknosis and cytoplasmic vacuoles. Pretransplant IL-2(P) levels of patients who subsequently rejected were elevated, with 19/21 patients with preoperative IL-2 levels greater than 15 ng/ml having subsequent rejections. In contrast, pretransplant creatinine, urine cytology, and IL-2(U) levels showed no correlation to subsequent clinical course.(ABSTRACT TRUNCATED AT 400 WORDS)

Prevalence of bovine venereal disease in the Victoria River District of the Northern Territory: likely economic effects and practicable control measures

Area prevalences of bovine Campylobacteriosis and Trichomoniasis in the Victoria River District (VRD) of the Northern Territory were determined by a survey of bulls. Eighty-seven percent of herds were infected with Campylobacteriosis and 65.6 percent were infected with Trichomoniasis. The levels of infection recorded are likely to be causing significant reductions in reproductive rates. Control of Campylobacteriosis is unlikely to be practicable on a district basis, but in some herds it may be possible to implement control measures in select groups subject to good stock control. Trichomoniasis control measures are generally not implementable in the VRD management situation. Computer modelling suggests that control measures are unlikely to be profitable in commercial herds. There is a need for field investigations to confirm this.

Clinical, hematologic, and immunologic cross-sectional evaluation of individuals exposed to human immunodeficiency virus type-2 (HIV-2)

We studied the clinical status and certain hematologic and immunologic parameters in healthy prostitutes from Dakar, Senegal who were seropositive for antibodies to human immunodeficiency virus type-2 (HIV-2). Generalized lymphadenopathy and clinical signs or symptoms similar to those which are seen with human immunodeficiency virus type-1 (HIV-1) infection were not present. Comparison to seronegative prostitutes and minor surgery control patients were made and significant elevations were seen in T8 lymphocytes (p = .03), IgG (p = .0001), and beta 2-microglobulin (p = .03). The mean T4 lymphocyte count in seropositive prostitutes was lower than in seronegative prostitutes (757 vs. 1179, p = .15), but this difference was not statistically significant and appeared to be correlated with age. No significant differences were noted between the seronegative and seropositive prostitutes in lymphocyte stimulation studies to certain mitogens. Antilymphocyte antibodies above background were not present in either population. We conclude that HIV-2 is a sexually transmitted agent that produces immunologic alterations consistent with a persistent viral infection. HIV-2 seropositive prostitutes studied to date do not show clinical signs of immune suppression, as has been described with HIV-1 infection. The pathogenic potential of HIV-2 appears to differ from that of HIV-1, the etiologic agent of the AIDS pandemic.

Referral patterns for psychiatric consultation in a large general hospital

Referrals for psychiatric consultation from all inpatient and outpatient departments in a large general hospital were analysed. There were 597 referrals--the combined inpatient and outpatient referral rate was approximately 0.78% and the inpatient rate 1.8%. The most common reasons for referral were parasuicide, depression/symptoms of depression, abnormal behaviour and alcohol abuse. Depressive disorders, drug dependence and neuroses were the most common diagnoses made. Medication was prescribed in 38% of cases and psychotherapy was offered in 18%. In 21% of cases the patient was either managed in his original ward or transferred back to the ward with advice regarding management. In 79% of cases management was within the Department of Psychiatry; many of these patients required concurrent treatment from the referring doctor for a physical disorder. The value of improving the quality and availability of consultation-liaison psychiatry services is discussed.

Medical psychology--its growth and development in South African medical schools

New training models and programmes in the teaching of clinical psychology associated with medically applied psychology at medical schools are developing in South Africa. However, a recent survey showed that a minimum number of full-time clinical psychologists is employed by medical schools in South Africa. How the few who are so employed fare away from their 'home base' is also explored as well as what their contributions are in such settings and in providing medical psychological services in general hospitals. These findings are discussed with reference to a developing country such as South Africa. Methods are proposed to further enhance the development of medical psychology and the effective contribution of clinical psychology to medical and related education, and its functioning as a bridge across the body-mind dichotomy within promotive and preventive healing systems.