Tumor angiogenesis. Rapid induction of endothelial mitoses demonstrated by autoradiography.

Walker ascites tumor cells and an extract derived from such cells (tumor angiogenesis factor, TAF) were injected into the subcutaneous tissue of rats by using a dorsal air sac technique. At intervals thereafter, thymidine-(3)H was injected into the air sac and the tissues were examined by autoradiography and electron microscopy. Autoradiographs of 1micro thick Epon sections showed thymidine-(3)H labeling in endothelial cells of small vessels 1-3 mm from the site of implantation, as early as 6-8 hr after exposure to live tumor cells At this time interval endothelial cells appeared histologically normal. DNA synthesis by endothelium subsequently increased and within 48 hr new blood vessel formation was detected. The presence of thymidine-(3)H-labeled endothelial nuclei, endothelial mitoses, and regenerating-type endothelium was confirmed by electron microscopy. TAF also induced neovascularization and endothelial cell DNA synthesis after 48 hr. A similar response was not evoked in saline controls. Formic acid, which elicited a more intense inflammatory response, was associated with less endothelial labeling and neovascularization at the times studied. Pericytes and other connective tissue cells were also stimulated by live tumor cells and TAF. The mechanism of new blood vessel formation induced by tumors is still unknown but our findings argue against cytoplasmic contact or nonspecific inflammation as prerequisites for tumor angiogenesis.

Complement-independent adherence of Escherichia coli to complement receptors in vitro.

We studied adherence to human cells by a strain of Escherichia coli. Adherence to erythrocytes was assessed directly by phase-contrast microscopy and indirectly by hemagglutination; adherence to peripheral blood leukocytes, using radiolabeled bacteria and subsequent determination of leukocyte-associated radioactivity; and adherence to renal glomeruli, by microscopy of fluoresceinated bacteria and of Gram-stained nonfluoresceinated bacteria. In serum-free systems, E. coli of this strain adhered to human erythrocytes, which have surface receptors for the third component of complement (C3), but not to erythrocytes from species lacking this receptor. 1 mM trypan blue, a reagent that inhibits complement receptor function, inhibited adherence to human erythrocytes, as well as adherence to leukocytes and glomeruli. Preincubation of erythrocytes and leukocytes with complement-coated zymosan particles partially blocked subsequent bacterial adherence. Incubation of human erythrocytes with aging human serum, with trypsin-cleaved C3, or with C3 cleaved by the classical pathway convertase (EAC142)-all of which treatments deposited C3 on the erythrocyte surface, presumably at C3 receptors-inhibited subsequent E. coli adherence. Finally, incubation of E. coli with rabbit antiserum to human C3 blocked adherence to erythrocytes.Bacterial hemagglutination and erythrocyte adherence were not inhibited by mannose in concentrations up to 2.5%. And this strain of E. coli did not adhere to or agglutinate guinea pig erythrocytes, the usual test particle used for demonstration of common pili. Finally, electron microscopy of adherent bacteria showed only rare surface pili. In contrast, adherence to and agglutination of guinea pig erythrocytes by a stock piliated E. coli was inhibited by mannose but not by trypan blue. We conclude that organisms of this strain of E. coli adhere to human erythrocytes, leukocytes, and glomeruli at complement receptors. Complement is not required for this interaction. Adherence apparently involves a C3-like structure on the bacterial surface, but bacterial surface pili play no role. The physiological or pathological role of this adherence is not apparent, but study of this phenomenon may elucidate functions of complement receptors on various cells.

Hypertension in radiation nephritis. Report of a patient with unilateral disease, elevated renin activity levels, and reversal after unilateral nephrectomy.

A patient received intensive radiation to the right renal area for abdominal Hodgkin's disease and approximately ten years later severe hypertension developed. The presence of radiation nephritis with a severely shrunken right kidney was demonstrated and this was accompanied by a substantial increase in renin activity from the right kidney. Treatment with propranolol hydrochloride temporarily lowered the blood pressure and peripheral renin activity levels. Subsequent right nephrectomy resulted in a decrease in renin activity and a reversal of the hypertension. The data implicate a renin angiotensin mechanism as probable cause of hypertension in radiation nephritis.

Bowel-associated dermatosis-arthritis syndrome. Immune complex-mediated vessel damage and increased neutrophil migration.

In a recent report we described a syndrome, identical to bowel-bypass syndrome, that occurred in four patients who had not had bypass surgery. Herein, circulating immune complexes (CICs) and neutrophil migration are evaluated in three of those four patients to test the hypothesis that the cutaneous lesions might have resulted from interaction between immune complex-mediated vessel damage and increased neutrophil migration. In vitro assays indicated that CICs were present in one of two patients and "histamine trap" test evidence for CICs was present in both patients tested. Although serum from the three patients appeared to increase neutrophil movement, statistically significant increases were not observed when data were pooled in this small study group. Preliminary results suggest that immune complex-mediated vessel damage, followed by extensive accumulation of neutrophils, may cause the pustular vasculitis in the bowel-associated dermatosis-arthritis syndrome.

Thalidomide effects in Behçet's syndrome and pustular vasculitis.

Pustular vasculitis is a new disease concept that links cutaneous, and possibly systemic, aspects of Behçet's, bowel bypass, bowel-associated dermatosis-arthritis, and disseminated gonorrhea syndromes. The pathomechanism of pustular vasculitic lesion generation may relate to circulating immune complex (CIC)-mediated vessel damage and serum enhancement of neutrophil migration. Thalidomide, an oral pharmaceutical available on strict protocol, has therapeutic effects based on proposed modulation of CIC- and neutrophil-mediated cytotoxicity. Thalidomide therapy was started for four patients with significant morbidity from Behçet's syndrome and for one patient with bowel-associated dermatosis-arthritis syndrome. Clinical benefit was dramatic in all patients who completed sequential four-week "on" and "off" thalidomide therapeutic cycles. In three of four patients, in vivo testing for CIC after histamine injection immunopathology converted from positive (immunoreactant deposition in dermal vasculature [four hours after histamine] and CIC-mediated vasculitis [24 hours after histamine]) to negative during therapy. No effects were noted on neutrophil migration or on the LFA-1/Mac-1/p150,95 family of glycoproteins associated with neutrophil adherence as assessed qualitatively by tritium labelling of neutrophil cell surfaces. In this small patient group, thalidomide was a clinically effective, safe (with rigid monitoring) therapy whose mechanism of action may relate more to inhibitory effects on CIC-induced vasculitis than to effects on neutrophil-mediated cytotoxicity.

Fibrillary (immunotactoid) glomerulopathy. A possible role for kappa light chain in its etiology and/or pathogenesis.

The initial clinical manifestations, course, and immunopathologic findings of renal biopsies of nine patients with fibrillary glomerulopathy are reported. Their first symptoms and courses were variable, but proteinuria and renal failure were common. While some patients required hemodialysis soon after coming for treatment, others progressed to renal failure over several years. Three patients had monoclonal gammopathy; one of them had an isolated, transient, Bence-Jones proteinuria. The main pathologic features are glomerular enlargement, mesangial expansion, and mild hypercellularity. Congo red and thioflavin stains were negative. Kappa chain, either alone or with lambda chain and IgG, were the predominant immunoreactants. Ultrastructurally, the presence of coarse fibrils of 15-25 nm was characteristic, but there were also granular deposits in the capillary wall that occurred in a band-like pattern in the inner half of the glomerular basement membrane in a manner similar to the deposits seen in light chain deposit disease. The immunofluorescence and ultrastructural findings suggest that light chains (especially kappa) may be significant in the pathogenesis of fibrillary glomerulopathy and that there may be a relationship with light chain deposit disease.

A blinded retrospective analysis of renal allograft pathology using the Banff schema: implications for clinical management.

BACKGROUND: We sought to determine whether diagnoses established through the Banff schema for evaluation of renal allograft pathology have implications for clinical management, compared with diagnoses established using descriptive terminology. METHODS: All patients included in this study had mild to severe allograft rejection diagnosed, and, as part of a therapeutic protocol, they received OKT3 as primary anti-rejection therapy. We conducted a retrospective review of their renal allograft biopsy specimens and reclassified them, using the Banff schema, without knowledge of clinical information, laboratory data, or previous biopsy interpretation. Although there is no strict correspondence between descriptive diagnostic terminology and the criteria used in the Banff schema, for the purpose of comparisons, the following approximation was used: mild and mild to moderate rejection=Banff borderline and Banff grade 1, moderate and moderate to severe rejection=Banff grades 2A and 2B, and severe rejection=Banff grade 3. The diagnosis was considered concordant when the diagnosis by descriptive terminology and Banff grading were within the adopted approximation. RESULTS: Of 96 biopsies specimens with mild to severe allograft rejection, 10 were insufficient for diagnosis, and three had changes of chronic allograft rejection. Of the remaining 83 biopsy specimens, 34 (41%) were concordant in interpretation of rejection grades, whereas 49 (59%) were discrepant. The greatest degree of concordance was in grades 2A (66.7%, 18 of 27) and 2B (64.7% 11 of 17), and the lowest was in the borderline category (11.8%, 2 of 17). The greatest degree of discrepancy was in normal and grade 3 (100%, 3 of 3 and 2 of 2, respectively), and the lowest was in grade 2A (33.3%, 9 of 27). Although primary anti-rejection therapy with OKT3 resulted in a high reversal rate of rejection (98%), there were 5 deaths, 12 graft loses, six episodes of serious infections, and three malignancies in this group of patients during a mean follow-up period of approximately 38 months. CONCLUSIONS: Because patients with borderline changes and grades 1 and 2A rejection may be treated differently from patients with higher grades (2B and 3), the use of the Banff schema may allow for better adjustment of immunosuppressive therapy in response to specific grades of acute allograft rejection and may result in decreased complications of immunosuppressive therapy.

Efficacy of OKT3 as primary therapy for histologically confirmed acute renal allograft rejection.

BACKGROUND: OKT3 is often used as primary treatment for acute renal allograft rejection. In a retrospective study, we sought to determine the efficacy of OKT3 as a first-line agent in reversing histologically confirmed acute renal allograft rejection. METHODS: Patients with mild to moderate, moderate, or severe acute cellular and acute vascular rejection who had not received any other anti-rejection treatment were included in this analysis. A total of 88 patients, who received OKT3 between 1987 and 1995, fulfilled these criteria. RESULT: Seventy of these patients were renal transplant recipients, and 18 were combined kidney and pancreas transplant recipients. The median time to the diagnosis of rejection from transplantation was 32 days (range, 6 days to 13 years). On histology, 6 were graded as mild to moderate, 36 as moderate, 29 as moderate to severe, and 17 as severe rejection. The mean baseline serum creatinine was 1.62 mg/dl (range, 0.7-10.1 mg/dl), and the mean serum creatinine at the time of diagnosis of rejection was 2.60 mg/dl (range, 1.4-12.7 mg/dl) (P=<0.0001). The mean duration of OKT3 treatment was 11.2 days (range, 8-18 days). The mean serum creatinine at the end of OKT3 treatment was 1.73 mg/dl (range, 0.6-5.0 mg/dl; P=0.24 compared with baseline serum creatinine). Rejection was reversed in 86 (98%) patients. Graft survival at 1 year after OKT3 therapy was 87.5% (77 of 88). At a mean follow-up of 38 months, 8 patients had died and 26 grafts were lost. The mean serum creatinine level in the 64 patients with a functioning graft was 1.76 mg/dl (range, 0.8-4.0 mg/dl) at the last follow-up. CONCLUSION: OKT3 when utilized as first-line therapy reversed 98% of the acute rejection episodes, with a 1-year post-OKT3 graft survival of 87.5%.

Rescue therapy with tacrolimus after combined kidney/pancreas and isolated pancreas transplantation in patients with severe cyclosporine nephrotoxicity.

This study details 11 pancreas transplant recipients (10 combined kidney and pancreas and 1 pancreas after kidney) who were converted to tacrolimus (FK506) due to acute severe cyclosporine nephrotoxicity in 8 cases and persistent rejection with cyclosporine toxicity in three cases. Arteriolopathy was documented by renal histology in all cases. Cyclosporine was discontinued for 24 hr immediately prior to initiation of tacrolimus. Tacrolimus was started orally at 0.1 mg/kg twice daily with dose adjustments to maintain whole blood trough levels of 8-15 ng/mL by IMx. Tacrolimus was initiated a mean of 14.5 months (range 1-81) after pancreas transplantation. The mean serum creatinine level had increased to 2.9 mg/dl from 1.0 mg/dl at the diagnosis of cyclosporine arteriolopathy (P=0.003). The mean serum creatinine and blood glucose levels at the time of initiation of tacrolimus were 2.1 mg/dl and 104 mg/dl, respectively. Serum creatinine was 1.7 mg/dl, 1.9 mg/dl, 1.8 mg/dl, and 1.7 mg/dl after 1, 2, 3, and 6 months of tacrolimus therapy, respectively; ANOVA (P = 0.02). The corresponding blood glucose levels were 117 mg/dl, 112 mg/dl, 109 mg/dl, and 116 mg/dl, respectively (P=NS). Normal C-peptide levels were present before (5.9 ng/ml) and after (6.2 ng/ml), the initiation of tacrolimus therapy (P=NS), and mean HbA1C was 6.1% before and 6.3% after tacrolimus therapy, (P=NS). There were 4 episodes of acute rejection, 3 responded to intravenous methylprednisolone, and 1 required OKT3 during tacrolimus therapy. Reversible tacrolimus nephrotoxicity was noted in three patients without any evidence of progressive vasculopathy. All 11 patients are alive, and 10/11 kidney and pancreas grafts are functioning with a mean follow-up of 7.7 months (range 5-10). In this study, conversion from cyclosporine to tacrolimus in kidney and pancreas recipients resulted in improvement and stabilization of renal function while maintaining stable blood glucose, C peptide, and HbA1C levels.

Immediate allograft dysfunction due to atheroembolic disease.

Atheroembolic disease is a known cause of renal failure following invasive vascular procedures in patients with atherosclerosis. It is, however, not generally associated with renal transplant dysfunction. We report on a case of donor-transmitted atheroembolic renal disease, which led to an immediate loss of the transplant kidney in the operating room. Risk factors associated with this condition and methods to prevent this complication are discussed.

Pathogenesis of early nephritis in lupus prone mice with a genetic accelerating (lpr) factor.

We investigated the relative roles of B cell activity, circulating immune complexes, complement concentration and kinetics of disappearance and uptake of immune complexes from the circulation in the pathogenesis of early nephritis of MRL/lpr mice. In comparison to data in control (C57BL/6J) mice, B cell activity was enhanced and the concentration of autoantibodies and endogenous immune complexes in plasma were increased, whereas complement (C3) concentration was not significantly different in MRL/lpr mice. The kinetics of disappearance of radiolabeled immune complexes from the circulation were similar in MRL/lpr and control mice, whereas uptake of radiolabeled immune complexes by the liver was decreased in MRL/lpr mice. Features of polyclonal B cell activation and impaired mononuclear phagocyte function are early events that may set the stage for progressive systemic involvement in MRL/lpr mice.

Mechanism of localization of immune complexes in NZB/W mice with early nephritis.

We investigated the pathogenesis of mesangial proliferative lupus nephritis in NZB/W mice under conditions that allowed us to examine removal of immune complexes from the circulation, uptake by the mononuclear phagocyte system, and localization in kidney tissue. These studies were performed at a time when variables such as the quantity of endogenous immune complexes, complement concentration, and carrier state of blood cells (platelets) were controlled. NZB/W mice and C57BL/6 (control) mice showed comparable kinetics for removal of a subsaturating dose of immune complexes (2.5 mg bovine serum albumin-antibovine serum albumin) from the circulation; additionally, the liver uptake and kidney localization of these immune complexes were comparable between NZB/W and control mice. The localization of immune complexes in the glomerular mesangium of NZB/W mice could not be attributed to enhanced production of endogenous immune complexes, to decreased removal of immune complexes from the circulation, to impaired uptake by the liver, or to complement concentration and carrier state of blood cells. It appears, by exclusion, that mesangial deposits of immunoreactants in early lupus nephritis may result from interaction of antibodies with antigens in mesangia.

Granulomatous interstitial nephritis.

Granulomatous interstitial nephritis is a rare condition whose pathogenesis is poorly understood. Of 203 renal biopsies performed between 1974 to 1994 in which interstitial nephritis was the predominant change, granulomata occurred in 12. The authors reviewed the records of these patients and performed immunopathologic and immunohistochemical studies in their biopsies to characterize the phenotype of infiltrating cells. The authors used markers for T cells, B cells, and macrophages, and determined whether they were activated through assessment of upregulation of HLA-DR molecules. Additionally, the authors attempted to delineate whether or not tubules contributed to giant cell formation through assessment of intermediate filament for keratins and macrophage markers in epithelioid cells. Drug (aspirin, gentamycin, or combination of drugs), infection (Echerichia coli or various organisms), and sarcoidosis accounted for granulomatous inflammation in three patients each, Wegener's granulomatosis and oxalosis resulting from intestinal bypass in one patient each, and in one patient the possible cause could not be determined. Except for biopsies of granulomatous inflammation resulting from infection, in which neutrophils predominated, in all other biopsies, T cells and macrophages made up most of the inflammatory cell infiltrate. HLA-DR was upregulated in mononuclear cells infiltrating the interstitium and was expressed in proximal tubular cells and endothelial cells in all but biopsies of patients with sarcoidosis. In no instance was there evidence that tubules contributed epithelial cells to giant cell formation. These findings are consistent with the notion that granulomatous interstitial nephritis is a cell-mediated form of tissue injury in which T cell-macrophage seem to play a major role.

Glomerulonephritis with coexistent immune deposits and antibasement membrane activity.

Six patients with coexistent antiglomerular basement membrane disease and granular immunoreactants in the glomerular basement membrane and mesangium are discussed. These six patients represent 35% of all patients with antiglomerular basement membrane nephritis examined over 10 years. All patients presented with acute, oliguric renal failure, and rapid deterioration in renal function. In all patients the pathogenetic role of the antiglomerular basement membrane antibody was confirmed by the demonstration of linear deposits of IgG along the glomerular basement membrane and antiglomerular basement membrane antibody activity in the serum or renal eluates, or both. Evidence for the existence of concurrent immune aggregates was obtained by immunofluorescence studies and electron microscopy. Radioimmunoassays, which were performed in two patients to detect circulating immune complexes, however, yielded negative results. The possible mechanisms concerned in the evolution of this condition and their potential implications are reviewed.

Diabetic nephropathy as the mode of presentation of diabetes mellitus.

Diabetic nephropathy have only rarely been described in patients who have minimal or no glucose intolerance. We herein report the case of a 59-yr-old man who presented with nephrotic syndrome and minimal glucose intolerance whose renal biopsy showed the nodular (Kimmelsteil-Wilson) and diffuse glomerulosclerosis lesions characteristic of diabetes. We critically review the literature on this subject, pointing out the pitfalls in diagnosis and establishing strict criteria for the diagnosis of diabetic nephropathy in patients wihout overt clinical diabetes.

Mechanism-oriented assessment of isotretinoin in chronic or subacute cutaneous lupus erythematosus.

Eight of ten patients with chronic or subacute cutaneous lupus erythematosus completed 16 weeks of oral isotretinoin therapy (80 mg/day). All eight patients noted an excellent clinical response without significant side effects. (Two patients did not return to initial two-week follow-up.) Peripheral blood B- and T-cell counts were unaffected by therapy. Therapy was associated with resolution of routine histopathologic abnormalities, conversion of abnormal lesional direct immunofluorescence microscopy to normal, normalization of the epidermis on electron microscopy, and reduction of all T cells near the dermoepidermal junction without change in ratio of T-helper/inducer cells to T-suppressor/cytotoxic cells. Isotretinoin is a clinically effective short-term therapy for chronic or possibly for subacute cutaneous lupus erythematosus. The primary mechanism of action remains unestablished.

[Measurement of the spontaneous growth hormone increase in short children. Diagnostic significance and neuroendocrine implications]. / Valutazione dell'increzione spontanea di ormone della crescita in bambini con bassa statura. Significato diagnostico e implicazioni neuroendocrine.

The assessment of growth hormone deficiency (GHD) in children with growth retardation is frequently difficult. The diagnostic reliability of standard pharmacological GH provocative tests has been questioned and several investigators have focussed on measurement of spontaneous GH secretion at frequent intervals over periods of 12-24 hours, with mathematical analysis of resulting secretory patterns. The aim of our study was to assess GH secretion in children with growth retardation, either in prepuberal and puberal ages, in order 1) to evaluate the diagnostic relevance of spontaneous GH secretion in comparison to tests, and 2) to gain neuroendocrine interpretations of GH secretion. We investigated 58 short children (height < 5th centile), 35 males, aged 6.4-15 years, without chronic diseases or dysmorphic syndromes. All subjects were divided into 3 groups, either in prepubertal and pubertal ages: normal (normal growth rate, within -0.80 HVSDS; normal GH peak after standard clonidine test > 7 ng/ml; 15 prepubertal, 8 pubertal); slow-growing (growth rate lower than -0.80 SDS; normal GH peak to test; 13 prepubertal, 13 pubertal); GH deficit (growth rate lower than -0.80 SDS; GH peak to test < 7 ng/ml; 6 prepubertal, 3 pubertal). In all children spontaneous GH secretion was evaluated for 24-hrs, 12-hrs daily and 12-hrs overnight, sampling every 30 minutes. The results were analyzed by the PULSAR computer program to determine number, height, area and amplitude of pulses and the baseline and GH secretory areas under and over baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Behçet's syndrome. Immunopathologic and histopathologic assessment of pathergy lesions is useful in diagnosis and follow-up.

Behçet's syndrome is a complex multisystem disease that, due to the absence of a pathognomonic laboratory test, must be diagnosed using clinical criteria. Clinical pathergy testing, the induction of a sterile pustule 24 hours after cutaneous trauma, has been proposed as a useful adjunct to diagnosis. We have expanded this concept by showing the usefulness of examining pathergy lesions by routine and immunofluorescence microscopy in the diagnosis of nine patients with Behçet's syndrome. Furthermore, histopathologic pathergy assessments correlated with clinical disease activity and/or response to experimental oral thalidomide therapy in five of six patients with Behçet's syndrome who were retested.

[Ectopic thyroid and late-onset functional deficit of the thyroid gland]. / Ectopia tiroidea e deficit funzionale tiroideo ad esordio tardivo.

PURPOSE: To evaluate retrospectively the incidence of ectopic thyroid gland causing hypothyroidism in patients referred to "Di Venere" Hospital, Bari. PATIENTS AND METHODS: Over a period of 14 years, ectopic thyroid gland has been detected by thyroid scan in 56 out of 122 patients with hypothyroidism due to congenital thyroid abnormalities. Of these 56 patients, 48 were < 1 year old, 2 were < 2 years old, while 8 with late onset of the disease were 7 to 35 years old. RESULTS: Among the eight patients with late onset hypothyroidism, 3 had normal serum levels of thyroid hormones at birth. Overall, an ectopic thyroid gland was observed in 6 out of 32 (18.7%) patients with hypothyroidism beginning between 2.5 and 14 years of age. CONCLUSIONS: Thyroid scan is a safe and effective procedure in the diagnosis of ectopic thyroid gland in neonatal patients. It should be recommended as neonatal screening in order to prevent irreversible damage to central nervous system.

Cardiac magnetic resonance imaging: technique and anatomy.

Recent advances achieved in Magnetic Resonance Imaging equipment and procedures allow a thorough study of the heart, yielding anatomic, functional and angiographic information. Spin-echo sequences are specific for heart morphology while gradient-echo sequences are fundamental to the functional study. Fast sequences reduce the examination times with the possibility of single breath-hold images. Coronary arteries can be directly visualized and cardiac perfusion can be assessed. Velocity encoded images allow flow quantification and with myocardial tagging, cardiac mechanics is accurately defined.