Evaluation of humoral immune response to donor HLA after implantation of cellularized versus decellularized human heart valve allografts.

We have evaluated the development of antibodies in response to donor allograft valve implant in patients who received cellularized and decellularized allografts and determined possible immunogenic epitopes considered responsible for antibodies reactivity. Serum samples from all recipients who received cellularized allografts or decellularized allografts were collected before valve replacement and at 5, 10, 30 and 90 days post-operatively and frozen until required. Tests were performed using the Luminex-based single human leukocyte antigen (HLA)-A, -B, -C and HLA-DR, -DQ antigen microsphere assay. To determine possible immunogenic epitopes, we used the HLAMatchmaker (HLAMM) software if applicable. Decellularized grafts elicited lower levels of anti-HLA class I and II antibody formation after implantation than cellularized allografts. All patients from cellularized group presented donor-specific antibodies class I and II within 3 months of observation period. In HLAMM analysis, the cellularized group had significantly higher numbers of immunogenic epitopes than decellularized group for both class I and II (p: 0.002 - cl I / p: 0.009 - cl II / p: 0.004 - cl I and II). Our findings demonstrate that the anti-HLA antibodies detected in the cellularized group were against donor HLA possible immunogenic epitopes and that in the decellularized group the anti-HLA antibodies were not against donor HLA possible immunogenic epitopes. These findings lead us to suggest that choosing sodium dodecyl sulfate decellularization process is the best alternative to decrease the immunogenicity of allograft valve transplant.

Cholinergic agonists attenuate renal ischemia-reperfusion injury in rats.

Inflammation plays a significant role in the pathophysiology of renal ischemia-reperfusion injury. Local inflammation is modulated by the brain via the vagus nerve and nicotinic acetylcholine receptors such that electrical or pharmacologic stimulation of this cholinergic anti-inflammatory pathway results in suppression of proinflammatory cytokine production. We examined the effects of cholinergic stimulation using agonists, nicotine or GTS-21, given before or after bilateral renal ischemia-reperfusion injury in rats. Pretreatment of rats with either agonist significantly attenuated renal dysfunction and tubular necrosis induced by renal ischemia. Similarly, tumor necrosis factor-alpha protein expression and leukocyte infiltration of the kidney were markedly reduced following treatment with cholinergic agonists. We found functional nicotinic acetylcholine receptors were present on rat proximal tubule epithelial cells. Cholinergic stimulation significantly decreased tubular necrosis in vagotomized rats after injury, implying an intact vagus nerve is not required for this renoprotective effect.

Reversible renal allograft dysfunction and proteinuria from nutcracker-like syndrome: a case report.

A 27-year-old Hispanic man with hypertension and renal failure was on hemodialysis for 4 years prior to receiving a living donor renal transplant from his 19-year-old sister. His serum creatinine decreased to 1.7 mg/dL at 3 weeks posttransplant with a urine protein creatinine ratio (UP) of 0.1 (g/g). Over the next 2 months, he experienced repeated episodes of allograft dysfunction with elevation of creatinine and proteinuria levels, associated with a lymphocele. Doppler studies of the allograft revealed renal vein compression. His symptoms responded to aspiration of the fluid collection, resolving completely with surgical drainage. We believe that the episodes of allograft dysfunction and proteinuria were related to recurrent lymphocele, causing a nutcracker-like syndrome.

Antioxidant capacity of phenolic and related compounds: correlation among electrochemical, visible spectroscopy methods and structure-antioxidant activity.

We investigated the antioxidant activity of phenylpropionic acids--caffeic (CAF), ferulic (FER), para-coumaric (COU) and cinnamic (CIN)--and phenolic acids and related compounds--gallic (GAL), methyl gallate (meGAL), vanillic (VAN) and gentisic (GEN)--using visible spectroscopy, inhibition of nitroblue tetrazolium (NBT) reduction, and electrochemical methods including cyclic voltammetry and potentiometry. In the spectroscopic assays, only CAF, GAL and meGAL were able to inhibit NBT reduction. The same compounds showed the lowest oxidation potentials (Epa) and the highest redox potentials deltaE) in the cyclic voltammetric and potentiometric studies, respectively. In addition, it was observed that the greater the number of hydroxyls linked to the aromatic ring, the greater was the antioxidant activity of the analysed compounds. The correlations of Spermann--used to compare the methods between themselves and the methods with the relationship structure-antioxidant activity--were r = -0.9762 for the cyclic voltammetric-potentiometric methods. r = 0.8333 for the inhibition of NBT reduction-potentiometric methods and r = -0.8095 for the inhibition of NBT reduction-cyclic voltammetric methods. The correlations for cyclic voltammetric, potentiometric and inhibition of NBT reduction methods-number of hydroxyls linked to the aromatic ring were r = -0.9636, 0.9636 and 0.9142, respectively. These findings indicate that the electrochemical methods together with spectroscopic studies are a good tool to evaluate the antioxidant activity of substances.

Increased renin immunostaining in preglomerular arterioles after myocardial infarction in the rat.

In previous studies we demonstrated that the intrarenal circulation is vasoconstricted in congestive heart failure (CHF) and that pharmacologic inhibition of the renin-angiotensin system reversed the renal hemodynamic abnormalities. In the current investigation we tested the hypothesis that renin expression is increased in renal arterioles in CHF. Male Sprague-Dawley rats were studied 4 to 6 weeks after left coronary artery ligation and compared with sham-operated and normal age-matched controls. Renal vascular trees were microdissected and immunostained with a polyclonal renin antiserum. Renin immunostaining was localized to the afferent arterioles, with a greater percentage of arterioles staining in rats with CHF (55.3% +/- 2.1%) than in sham-operated (43.9% +/- 1.9%) or normal age controls (37.6% +/- 2.2%). Rats with CHF more frequently exhibited multiple bands of renin staining within a single arteriole (24.9% +/- 1.8%) as compared with sham-operated (13.3% +/- 1.9%) and normal age controls (11.3% +/- 1.4%). Juxtaglomerular apparatus staining was similar in all groups. These data indicate that renin-containing cells are increased in the afferent arteriole in CHF. Increased renin in the preglomerular arterioles may activate local angiotensin production, leading to intrarenal vasoconstriction, reduced nephron blood flow, sodium and water retention, and worsening of congestive heart failure.

Ovarian hyperthecosis in the setting of portal hypertension.

Hepatocellular dysfunction and perturbed portal hemodynamics alter steroid metabolism. Men with liver disease have gynecomastia, although women similarly affected rarely show virilization. We report a 10-yr-old girl with portal hypertension and shunting associated with precocious puberty and ovarian hyperandrogenism. This was one of premature twin girls; neither had clitoromegaly or genital ambiguity. In one child, neonatal respiratory problems led to umbilical vein catheterization with subsequent development of portal hypertension. Pubic hair was first noted at age 6 yr, breasts at 7 yr, and severe acne and clitoromegaly at 10 yr. Baseline sex hormones were elevated: androstenedione (A), 413 ng/dL; testosterone (T), 226 ng/dL; and estradiol (E2), 160 pg/mL. Liver transaminases were within the normal range, however, the coagulation profile was mildly abnormal. Cosyntropin adrenal stimulation revealed no steroidogenic defect. Dexamethasone suppression reduced A and T slightly. LH-releasing hormone stimulation produced a pubertal rise in LH and FSH. Pelvic sonography showed a large right ovary with numerous follicles. Surgical exploration revealed symmetrically enlarged ovaries with dense capsules. Histology of ovarian wedge resections showed hyperthecosis; immunohistochemistry showed stromal cells expressing steroidogenic enzymes and proteins. One month postoperatively, A and T were unchanged from baseline, whereas E2 decreased to 56 pg/mL. A single dose of depot leuprolide acetate significantly reduced T. Subsequent treatment with oral contraceptives reduced T to 50 ng/dL, and cyclical menses occurred. We conclude that precocious puberty and ovarian hyperthecosis were induced in this young girl by elevated circulating levels of sex hormones, a consequence of portasystemic shunting and impaired hepatic steroid metabolism.

Remission of relapsing childhood nephrotic syndrome with mycophenolate mofetil.

We report a 21-year-old male with childhood-onset familial nephrotic syndrome and frequent relapses who manifested toxicity or treatment resistance to corticosteroids, cyclophosphamide, cyclosporin-A, and tacrolimus. Monotherapy with mycophenolate mofetil (MMF) resulted in maintenance of clinical remission for 14 months without noticeable toxicity, while allowing resolution of steroid-induced side effects. Our observation suggests that MMF may be useful in maintaining remission in nephrotic patients who manifest toxicity to standard immunosuppressive agents.

Renal cell carcinoma with X;1 translocation in a child with Klinefelter syndrome.

Klinefelter syndrome (KS) is a sex chromosome abnormality occurring in 1 in 1,000 males. An association with leukemia, germ cell tumor, and male breast cancer has been suggested in KS. Such information is important for professionals caring for KS patients as the condition is frequently not clinically recognizable until after puberty. We report on a renal cell carcinoma (RCC) in a 10-year-old boy with KS. He developed intermittent hematuria at age 10 years and was diagnosed with a right kidney mass, which on pathology was identified as RCC. In addition, he was known to have learning disabilities and language delays. Analysis of peripheral blood chromosomes showed a 47,XXY karyotype while analysis of tumor cells demonstrated clonal abnormalities including a translocation between chromosomes X and 1, designated 47,XXYc,t(X;1)(p11.2;q21)[6]/47,XXYc,t(X;1),r(Xp)[2]/46,X XYc,-X,t(X;1)[7]. Renal cell carcinoma is rare in childhood and is not previously reported in KS. The oncogenetic significance of the chromosomal regions involved in this translocation is discussed in relation to the congenital abnormality of the patient.

T-cell lymphoma associated with natural killer-like T-cell reaction.

We report a case of T-cell lymphoma showing in the peripheral blood (PB) exclusively T-lymphocytes with suppresser T-cell preponderance and a high percentage of natural killer (NK) marker positive cells by flow cytometry. A T-cell receptor (TCR) gene analysis of the PB leukocytes demonstrated rearrangements of TCRalpha, TCRbeta, and TCRgamma genes. Therefore, the phenotype and genotype appeared to be consistent with an NK-like T-cell leukemia/lymphoma. However, when the PB lymphocytes were separated by size, it was found that 80% of NK marker positive cells were in the smaller cell population, while the neoplastic cells were in the large cell gate. A diagnosis of T-cell lymphoma with reactive NK-like T-cells was finally confirmed by demonstrating the presence of both large atypical lymphoid cells and large granular lymphocytes (LGL) on PB smears. Although immunoperoxidase stain of bone marrow and colon showed positive T-cell markers in the tumor cell population, cytoplasmic granules could not be identified in tissue sections and, thus, a distinction between T-cell lymphoma and NK-like T-cell lymphoma could not be made by light microscopy until NK markers were studied. CD57 was demonstrated immunohistochemically in small lymphocytes but not in the large tumor cells in the colon. Electron microscopy, however, demonstrated LGL reaction to the lymphoma cells in the colonic biopsy. NK-like T-cell lymphoma usually carries a poorer prognosis than peripheral T-cell lymphoma, thus the distinction of these neoplasms is important. This study emphasizes that T-cell lymphoma may cause an LGL reaction or proliferation. If the lymphoma cells were of the same size as LGL, flow cytometric studies may have misled the diagnosis to NK-like T-cell-lymphoma.

Histiocyte-rich B-cell lymphoma.

This is the second report of histiocyte-rich B-cell lymphoma and the first case analyzed by flow cytometry and cytogenetic study. The immunophenotype determined by flow cytometry was that of a B-cell antigen-positive, surface immunoglobulin-negative B-cell lymphoma with 79% CD11c positive histiocytes. The lymphoid cells were composed of 76% neoplastic B-cells and 24% reactive T-cells. Immunohistochemical staining showed large numbers of histiocytes positive for CD68 and lysozyme in the lymph node and the bone marrow. Neoplastic lymphoid cells were positive for CD20, CD45, CD74 and CDw75. The monoclonality of the tumor cells was established by the evidence of rearrangements of the heavy chain and kappa light chain genes and a complex clonal cytogenetic abnormalities including t(8;14)(q11;q32). The tumor cells were large, pleomorphic lymphoid cells and showed no features resembling those of the L/H cells of Hodgkin's disease as previously reported. The rapidly progressive clinical course in the present case is consistent with the clinical features shown in the original study. The histiocytic component in this tumor is presumably recruited by a lymphokine with the nature of a growth factor from the tumor cells that may also be responsible for the rapid proliferation of the tumor cells and the aggressive clinical course. This entity merits special recognition because it leads to a predictable poor prognosis and because of its potential of being misdiagnosed as true histiocytic lymphoma.

Correlation between mutation in P53, p53 expression, cytogenetics, histologic type, and survival in patients with B-cell non-Hodgkin's lymphoma.

In the biology of a cell, the central role of p53 in controlling functions such as G1/S transition (check point) and DNA damage repair, and as a trigger of apoptosis, is well established. Somatic mutations or other changes in P53 have been reported in numerous tumor types, and in some of these, they are associated with poor prognosis. In this study, we examined 237 cytogenetically characterized B-cell non-Hodgkin's lymphomas (B-NHLs) for somatic changes in P53 by Southern blot analysis, by single-strand conformation polymorphism analysis (SSCP) of exon 5 through 9, and by direct sequencing of SSCP variants to determine the frequency and types of mutations and their clinical significance. In a portion of these (173 tumors), we also studied p53 expression by immunostaining. On Southern blots, no gross change was identified in P53 and no mutation was identified in exon 9. In exons 5 through 8, 27 different mutations were identified in 25 patients (23 single-base substitutions, 3 deletions, 1 duplication). Mutations in P53 were identified in 25 of 237 tumors (10.5%), which included 1 of 45 small lymphocytic lymphomas (SLLs), 2 of 38 follicular small cleaved-cell lymphomas (FSCCs), 2 of 35 follicular mixed small cleaved-cell and large-cell lymphomas (FMxs), 1 of 4 follicular large-cell lymphomas (FLCs), 1 of 14 diffuse small cleaved-cell lymphomas (DSCCs), 2 of 17 diffuse mixed small- and large-cell lymphomas (DMxs), and 16 of 84 diffuse large-cell lymphomas (DLCCs); the difference between the histologic groups was significant (P < .01). Among mantle-cell lymphoma (MC) patients, 3 of 10 had mutations. In 16 patients, the mutation was identified in specimens obtained at diagnosis. Mutation of transition type and transversion type occurred at a relative frequency of 2:1. Thirty percent occurred at CpG dinucleotide sequences and the codon for arginine was most frequently affected. Nineteen of 99 tumors with complex cytogenetic abnormalities, but none of 69 tumors with simple cytogenetic abnormalities, had mutations (P < .001). Similarly, 11 of 25 tumors with an abnormality of 17p and 8 of 143 tumors with apparently normal 17p had mutations (P < .0001). Positive correlations were found between a mutation and p53 expression (P < .001), between missense type mutations and p53 expression (P < .005), and between 17p abnormalities and p53 expression (P < .05). Twenty-two of 49 patients without mutation and 14 of 17 patients with mutations died (P < .05), but there was no significant difference in median survival. Similarly, 21 of 26 p53 positive patients died, whereas only 1 of 24 p53-negative patients died on-study (P < .001). Among p53-negative patients, mutation (P < .01) was positively associated with a fatal outcome. These findings indicate that in B-NHL, somatic changes in P53 were present in diagnostic specimens of all histologic types, but at a higher frequency in DLC and MC tumors. P53 mutation and/or expression has a negative influence on survival, and therefore can serve as prognostic indicators. Immunostaining for p53 is an effective way to screen for P53 changes in these tumors.

Metastatic malignant mesothelioma presenting as colonic polyps.

A 66-year-old male engineer diagnosed with malignant pleural mesothelioma 4 years previously had thoracotomy, radiotherapy, and chemotherapy. He was followed regularly with chest computed tomography (CT) scan and had been asymptomatic. During one of his physical examinations, routine sigmoidoscopy showed incidental colonic polyps which were biopsied. Subsequently, recurrence of pleural mesothelioma and peritoneal involvement by mesothelioma was documented. Two of the polyps showed metastatic malignant mesothelioma in the lamina propia which strongly resembled adenocarcinoma histologically causing difficulty in making definitive diagnosis. Review of the literature disclosed no previously documented similar occurrence. This case shows the importance of clinical history and ancillary laboratory procedures such as immunohistochemistry and electron microscopy to avoid diagnostic pitfalls.

Relationship between hairy cell leukemia variant and splenic lymphoma with villous lymphocytes: presentation of a new concept.

An unusual case of low-grade B-cell lymphoproliferative disorder with peripheral lymphocytosis and splenomegaly followed for 4 1/2 years is reported. During this period, the phenotype of the tumor cells in the blood changed from that of hairy cell leukemia (HCL)/chronic lymphocyte leukemia (CLL) to HCL/prolymphocytic leukemia (PLL), to PLL. The lymphoid population in the blood showed a mixture of hairy cells, villous lymphocytes, small lymphocytes, and prolymphocytes, corresponding to the phenotypes at various stages. Although relatively specific markers for CLL, HCL, and PLL, such as CD5, CD11c, CD22, CD25, and FMC-7, were positive at various stages, all these markers have also been demonstrated in a large study series of splenic lymphoma with villous lymphocytes (SLVL). In addition, the histologic pattern of the bone marrow biopsy and splenectomy specimen were not typical for HCL. This case can therefore be classified either as HCL variant or as SLVL. As SLVL assumes various cytologic and histologic patterns, which overlap with different lymphoproliferative disorders, especially HCL variants, this entity appears to represent a heterogeneous group of lymphomas/leukemias that may evolve into each other. The absence of activation of c-myc and bc1-2 oncogenes as well as mutation of p53 tumor suppressor gene, together with the presence of only one single rearranged band for both heavy chain and kappa light chain genes in our case suggest that these morphologically different lymphoid tumors may belong to the same family.

Minimal change nephropathy associated with sclerosing mesenteritis.

A 65-year-old man with sclerosing mesenteritis developed the nephrotic syndrome. Percutaneous renal biopsy revealed classical histologic findings of minimal change nephropathy with a mild interstitial nephritis. Immunomodulation with prednisone led to a rapid and complete remission of the proteinuria but did not alter the course of the underlying sclerosing mesenteritis. The association of lymphomatous and nonlymphomatous neoplasms with minimal change nephropathy has been well-described. Our review of the literature indicates a parallel association of malignant lymphoma with sclerosing mesenteritis and a variety of disorders that constitute a spectrum of disease. The occurrence of this histopathologic form of renal injury and therapeutic response in the setting of a known lymphoreticular disorder suggests a role for a generalized alteration in cell-mediated immunity and not a tumor-induced elaboration of a factor(s) that directly damages the glomerular filtration barrier.

Morphological, ultrastructural, and genetic characterization of an unusual T-cell lymphoma in a patient with sinus histiocytosis with massive lymphadenopathy.

Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare benign disease of unknown etiology. It is rarely associated with malignant lymphoma. This report documents the first case of a T-cell lymphoma, which developed in a patient with a 10-year history of SHML. The disease was complicated by hypereosinophilia and massive retroperitoneal lymphadenopathy. Histological examination of a cervical lymph node biopsy during the terminal phase identified a lymphoma composed of cells with morphological plasmacytoid features. Ultrastructurally, the tumor cells showed poorly developed cytoplasm, nuclei with peripheral chromatin clumping, and inconspicuous nucleoli. Cytogenetic studies showed two related clones. On immunohistochemical staining tumor cells were positive with monoclonal antibodies (mAb) CD3 and CD45RO. Southern blotting analysis identified clonal rearrangements in the T-cell receptor (TCR) alpha, beta and gamma genes. Thus, T-cell lineage of the tumor cells was established. In situ hybridization of interleukin-2 (IL-2) and interleukin-5 (IL-5) cDNA probes on tissue sections identified the synthesis of IL-5 by the eosinophils, suggesting an autocrine pathway of eosinophilopoiesis leading to hypereosinophilia in this patient.

Systemic lupus erythematosus complicated by thrombotic microangiopathy.

Seven patients with systemic lupus erythematosus (SLE) or SLE-like disease developed thrombotic microangiopathy. Prominent features of their acute illnesses were microangiopathic hemolytic anemia (7), thrombocytopenia (7), fever (1), nervous system disease (4), and renal dysfunction (5). Laboratory data were significant for antinuclear antibody (ANA) (7), DNA (5), low C3 level (3), low C4 level (2), antiphospholipid antibody (6), schistocytes (7), and lactate dehydrogenase > 500 (7). All seven patients received treatment that initially included steroids but later included cyclophosphamide (4), plasma infusion (1), plasmapheresis (5), intravenous gamma-globulin (2), anti-platelet agents (2), or vincristine (3). Six patients improved, and one patient expired during treatment. Of the six patients who survived this complication, three expired within the year following their acute illnesses. Histology, available in two cases, showed vascular changes consistent with a microangiopathic process. We conclude that the spectrum of vascular diseases in SLE extends beyond vasculitis to include noninflammatory vascular processes that can cause equally devastating complications.

Intracardiac teratoma in a child simulating an atrioventricular nodal tumor.

Intracardiac teratoma is an extremely rare pediatric neoplasm. We studied the case of a 6-year-old girl with a right intraventricular cardiac mass. The tumor consisted of clusters of monotonous round epithelial cells scattered in a dense fibrotic stroma and was thought to represent an atrioventricular nodal tumor. Three years later the tumor recurred, with multiple mature elements derived from all three germ layers, and was diagnosed as mature cystic teratoma. Still present, however, were multiple areas that were histologically similar to the earlier lesion. Immunostaining revealed strong positivity for insulin, glucagon, somatostatin, and chromogranin consistent with overgrown pancreatic islets of Langerhans within a mature teratoma.

Medullary thyroid carcinoma metastatic to breast masquerading as infiltrating lobular carcinoma.

Metastatic tumors to the breast from an extramammary site are rare entities and may present diagnostic difficulties for the surgical pathologist because of frequent histological similarities to primary neoplasms in this location. A case is reported of medullary thyroid carcinoma metastatic to the breast in a 28-year-old woman with a family history of MEN IIA (Sipple's) syndrome. Histological features resembled infiltrating lobular carcinoma and included the so-called "targetoid" and "Indian file" patterns. Immunostaining revealed the true nature of the lesion and was diffusely positive for calcitonin, chromogranin, and carcinoembryonic antigen. Electron microscopy disclosed typical neurosecretory granules confirming the diagnosis. A brief review of the literature and differential diagnosis is also presented.

Reversible monocular blindness complicating Churg-Strauss syndrome.

A 76-year-old woman hospitalized for treatment of an inferior vena cava thrombus was noted to have eosinophilia as well as asthma, peripheral neuropathy, jaw claudication and visual loss. Pathological review of a temporal artery biopsy revealed vasculitis with eosinophils but no giant cells. Treatment with high dose corticosteroids resulted in improvement of visual acuity from hand motion to 20/60. Whereas at least 6 cases of temporal artery involvement with Churg-Strauss syndrome have been reported, visual loss has occurred in only 3 patients. In each of these cases, visual loss was permanent.