Clinical Case of the Month: PERSISTENT HYPERTENSION IN A YOUNG WOMAN: A CLASSIC PRESENTATION OF CONN'S SYNDROME

Primary aldosteronism PA is a secondary cause of hypertension that is often missed due to inadequate clinical evaluation and the lack of classically described laboratory abnormalities. Based on guidelines from the Endocrine Society, primary aldosteronism should be suspected in young patients with moderate to severe hypertension, patients with hypertension and coexisting hypokalemia, any patient with hypertension and an incidental adrenal adenoma, and hypertension in the setting of a significant family history of early onset hypertension or cerebral vascular accident in a first degree relative less than 40 years of age.1 In previous years, primary aldosteronism was attributed to less than one percent of all causes of secondary hypertension. However, recent research and increased utilization of aldosterone plasma renin ratio ARR as a method for screening has led to the understanding that majority of patients with PA are not hypokalemic, and the current literature now places the incidence of PA between 5-13 percent. Additionally, a growing body of evidence has demonstrated inflammatory, fibrotic, and remodeling effects on the cardiovascular and renal tissue that appear to be independent of PA- induced hypertension. Therefore a high suspicion for PA must be incorporated into evaluation of hypertensive patients, as diagnosis and subsequent treatment not only improves blood pressure control, but also acts to diminish cardiovascular morbidity and mortality. Here we present a case of a young woman with a seven-year history of hypertension prior to receiving a diagnosis of Conn's Syndrome.

Complete morphologic and molecular remission after introduction of dasatinib in the treatment of a pediatric patient with t-cell acute lymphoblastic leukemia and ABL1 amplification

T-cell acute lymphoblastic leukemia (ALL) accounts for 15% of ALL cases in children and has been associated with a worse prognosis. Cytogenetic studies show an abnormal karyotype in 50-60% of the T-cell ALL patients; ABL1 fusions are present in approximately 8% of the cases. Dasatinib, a second-generation tyrosine kinase inhibitor, directly targets the BCR-ABL gene. We describe a pediatric case of T-cell ALL with amplification of the ABL1 gene in which remission was achieved only after the addition of dasatinib to conventional chemotherapy.

IL-7Rα deficiency in p53null mice exacerbates thymocyte telomere erosion and lymphomagenesis (161.6)

IL-7 is essential for T cell survival and development. IL-7 receptor (IL-7Rα) efficiency manifests SCID due to substantial thymocyte apoptosis. We hypothesized that IL-7Rαnull-induced apoptosis is partially mediated by an elevated p53 activity. To investigate the genetic association of IL-7Rα signaling with the p53 pathway, we generated IL-7Rαnullp53null (DKO) mice. DKO mice exhibited a marked reduction of apoptosis in developing T cells and an augmented thymic lymphomagenesis with telomere erosions and exacerbated chromosomal anomalies, including chromosome duplications, breaks, and translocations. In particular, Robertsonian translocations, in which telocentric chromosomes fuse at the centromeric region, and a complete loss of telomeres at the fusion site occurred frequently in DKO thymic lymphomas. Cellular and molecular investigations revealed that IL-7/IL-7Rα signaling withdrawal diminished the protein synthesis of POT1 (protection of telomere 1), a subunit of telomere protective complex shelterin, leading to telomere erosion and the activation of the p53 pathway. Blockade of IL-7/IL-7Rα signaling in IL-7-dependent p53null cells reduced POT1 expression and caused telomere and chromosome abnormalities similar to those observed in DKO lymphomas. This study underscores a novel function of IL-7/IL-7Rα during T cell development in regulating telomere integrity via POT1 expression and provides new insights into cytokine-mediated survival signals and T cell lymphomagenesis.

IL-7Rα deficiency in p53null mice exacerbates thymocyte telomere erosion and lymphomagenesis

Interleukin-7 (IL-7) is an essential T-cell survival cytokine. IL-7 receptor (IL-7Rα) deficiency severely impairs T-cell development due to substantial apoptosis. We hypothesized that IL-7Rα(null)-induced apoptosis is partially contributed by an elevated p53 activity. To investigate the genetic association of IL-7/IL-7Rα signaling with the p53 pathway, we generated IL-7Rα(null)p53(null) (DKO) mice. DKO mice exhibited a marked reduction of apoptosis in developing T cells and an augmented thymic lymphomagenesis with telomere erosions and exacerbated chromosomal anomalies, including chromosome duplications, breaks, and translocations. In particular, Robertsonian translocations, in which telocentric chromosomes fuse at the centromeric region, and a complete loss of telomeres at the fusion site occurred frequently in DKO thymic lymphomas. Cellular and molecular investigations revealed that IL-7/IL-7Rα signaling withdrawal diminished the protein synthesis of protection of telomere 1 (POT1), a subunit of telomere protective complex shelterin, leading to telomere erosion and the activation of the p53 pathway. Blockade of IL-7/IL-7Rα signaling in IL-7-dependent p53(null) cells reduced POT1 expression and caused telomere and chromosome abnormalities similar to those observed in DKO lymphomas. This study underscores a novel function of IL-7/IL-7Rα during T-cell development in regulating telomere integrity via POT1 expression and provides new insights into cytokine-mediated survival signals and T-cell lymphomagenesis.

Clinical case of the month. A rare case of Budd Chiari syndrome

Budd Chiari syndrome is a rare disorder resulting from hepatic venous outflow tract obstruction anywhere from the small hepatic veins to the suprahepatic inferior vena cava. This patient has a hypercoagulable state secondary to heterozygous mutation of factor V and the JAK2 mutation and is being anticoagulated. We hypothesize that the low protein C and low antithrombin III levels seen in this patient resulted from decreased synthetic function of the liver and were not indicative of actual deficiencies. Indeed, reports of coexisting protein C and antithrombin III deficiencies are not existent in the literature and likely are not compatible with life. All patients with BCS warrant a hypercoagulable work up and JAK2 mutation is increasingly recognized as a contributing factor, even in those patients without obvious signs of polycythemia vera.

Trp53 negatively regulates autoimmunity via the STAT3-Th17 axis (167.27)

Emerging evidence suggests that the tumor suppressor p53 is also a crucial regulatory factor for many physiological processes. Previous observations indicate that p53 negatively regulates inflammation via suppressing inflammatory cytokine production by antigen presenting cells. However, the role of p53 in regulating autoimmune effector T cells, such as IL-17 producing Th17 cells, is largely unknown. Here, we demonstrate that p53nullCD45.1 mice spontaneously develop autoimmunity associated with a significant increase in Th17 cells in their lymphoid and pathological tissues as well as elevated levels of inflammatory cytokines IL-6 and IL-17 in serum. This increase in Th17 response results largely from an increased sensitivity of p53nullCD45.1 T cells to IL-6 induced STAT3 phosphorylation. Administration of a STAT3 inhibitor to p53nullCD45.1 mice reduced the frequency of Th17 cells and alleviated autoimmune pathology. This is the first report, to our knowledge, revealing the contribution of T-cell p53 in the suppression of autoimmunity by controlling Th17 differentiation. This study suggests that p53 serves as a guardian of proper immunological functions and that the p53-STAT3-Th17 axis might be a therapeutic target for autoimmunity.

Natural killer cell lymphoma/leukemia with homozygous loss ofp27/kip1

We describe a case of natural killer (NK) cell lymphoma/leukemia with only an interstitial deletion in the short arm of chromosome 12 as the primary event. Fluorescence in situ hybridization revealed that the ETV6 locus (12p13) and subtelomeric sequences are not deleted in the process. The p27/kip1 locus (12p12-13), a candidate tumor suppressor gene, was deleted on the abnormal chromosome. Sequence analysis detected an adenine nucleotide deletion in the third codon of exon 1 leading to frameshift and premature termination at codon 41 of the retained copy of p27/kip1. To the best of our knowledge, this is the first report in literature on a NK cell lymphoma/leukemia with complete loss of p27/kip1.

Cross-talk between IL-7Ra signaling and p53 pathway during thymopoiesis and lymphomagenesis (86.8)

Thymopoiesis in IL-7Rα-/- mice is blocked at the CD4-CD8- double negative stage with failures in T cell receptor (TCR) γand β rearrangement. Early studies suggest that unsuccessful TCRβ rearrangement in mice defective in DNA damage repairs, incurring DNA double-strand breaks, results in p53 activation. However, it remains unknown whether p53 plays a role in the thymopoietic defect in IL-7Rα-/- mice. In this study, we demonstrated that p53 is highly activated in the thymocytes of IL-7Rα-/- mice. Considering the importance of p53 activity during TCR rearrangement and the observation of incomplete rescue of thymopoiesis in IL-7Rα-/- mice by modulating activities of Bcl-2 family members, we hypothesize that p53 activation may also contribute to the impaired thymopoiesis in IL-7Rα-/- mice and that temporal suppression of p53 activity by the IL-7Rα signaling facilitates thymopoiesis. With the generated IL-7Rα-/-p53-/- (DKO) mice, we found that p53 inactivation in IL-7Rα-/- background resulted in a 30-fold increase in thymic cellularity with increased TCRβ? cells. Furthermore, DKO mice developed thymic lymphoma at a higher incidence and died significantly earlier than p53-/- mice. Our study is the first to illustrate a functional interplay between IL-7Rα signaling and p53 pathways in facilitating TCRβ+ T cell development during thymopoiesis and lymphomagenesis.

DNA ploidy analysis as an adjunct for the detection of relapse in B-lineage acute lymphoblastic leukemia

Detection of relapse in acute lymphoblastic leukemia (ALL) is essential for proper management. However, immunophenotypic detection of relapse by flow cytometry in B-lineage ALL can be confounded by several factors, including lack of a unique immunophenotype and modulation of aberrant phenotypes after treatment. We hypothesized that flow cytometric DNA ploidy analysis may detect relapse in aneuploid ALL cases that might be missed by flow immunophenotyping. We retrospectively studied ALL cases at our institution between 1991 and 2003 (n = 114). Aneuploid populations were present at diagnosis in 32% of all patients. Sixty-five percent of all patients had "normal" leukemic immunophenotypes, defined as being similar to normal precursor B-cells, while 35% had "aberrant" immunophenotypes with myeloid or T antigen co-expression. In ALL cases that were originally aneuploid, follow-up ploidy-analysis detected relapsed disease in all cases which were also detected by flow immunophenotyping, suggesting that ploidy analysis is highly sensitive for detecting ALL relapse. However, in 5 cases in which the diagnosis of relapse could not be reliably made by flow immunophenotyping, ploidy analysis successfully detected aneuploid cells, i.e., relapse, in all five; these included 3 patients with normal and 2 with aberrant original immunophenotypes. These results suggest that it may be beneficial to perform ploidy analysis as an adjunct to flow immunophenotyping in following patients with B-lineage ALL who demonstrate aneuploidy at diagnosis.

Sustained remission from angioimmunoblastic T-cell lymphoma induced by alemtuzumab

BACKGROUND

A 73-year-old woman presented with acute lower back pain, fever, chills and arthralgias. She had previously had a positive protein derivative test with a negative chest X-ray; her medical history was also remarkable for a mitral valve prolapse. Initial symptoms resolved spontaneously without therapy, but fever recurred with associated arthralgias, myalgias, diffuse and worsening lymphadenopathy, splenomegaly, and bilateral pulmonary infiltrates.

INVESTIGATIONS

Physical examination, blood and urine cultures, MRI of the spine, echocardiogram, extensive serologies, serum and urine protein electrophoresis, immunofixation electrophoresis, bone-marrow aspiration and biopsy with flow cytometry, cytogenetics, and gene rearrangement studies, CT scan of the chest, abdomen and pelvis, whole-body PET, and lymph-node biopsy for histological examination, immunohistochemistry, and gene rearrangement studies.

DIAGNOSIS

Angioimmunoblastic T-cell lymphoma.

MANAGEMENT

Steroids (prednisone, methylprednisolone), levofloxacin, isoniazid with pyridoxine, ciclosporin A, methotrexate, alemtuzumab, broad-spectrum antibiotics, Pneumocystis carinii prophylaxis, vancomycin, and clindamycin.

Hemophagocytosis exacerbated by G-CSF/GM-CSF treatment in a patient with myelodysplasia

We describe a 75-year-old man with neutropenia in whom bone marrow aspirate and biopsy demonstrated hemophagocytosis associated with myelodysplasia (MDS). Therapy with granulocyte-colony stimulating factor (G-CSF) and granulocyte-monocyte-colony stimulating factor (GM-CSF) caused splenomegaly and severe thrombocytopenia, which recurred upon rechallenge. We propose that myeloid growth factors may be detrimental in patients with MDS-associated hemophagocytosis.

Prosaptide TX14A stimulates growth, migration, and invasion and activates the Raf-MEK-ERK-RSK-Elk-1 signaling pathway in prostate cancer cells

BACKGROUND

Prosaposin is a neurotrophic factor. Prosaposin knock-out mice have been reported to develop a number of abnormalities, including atrophy of the prostate gland and mitogen-activated protein kinase (MAPK)-inactivation in prostate epithelial cells. These abnormalities underscore a potential fundamental role in prostate development. The trophic factor activity of prosaposin has been localized at a specific amino terminal portion of the molecule that has been the source for a number of biologically active peptides called prosaptides (e.g., TX14A). The expression and function of prosaposin in prostate cancer is not known.

METHODS

Using conventional protein expression analysis, immunohistochemical staining, cell proliferation assays, and in vitro invasion assays, we determined the expression of prosaposin and the effect of prosaptide TX14A on cell growth/death protection, motility, invasion, and MAPK signal transduction pathway in prostate cancer cells.

RESULTS

We found a higher expression of prosaposin in androgen-independent (AI) prostate cancer cells (PC-3 and DU-145) than in androgen-dependent (AD) LNCaP or normal prostate epithelial cells. Immunohistochemical staining on benign and malignant prostate tissues revealed an intense cytoplasmic anti-prosaposin immunoreactivity in tumor cells, as well as stromal, endothelial, and inflammatory mononuclear cells. The intensity of staining was proportional to the overall Gleason's score. In addition, we demonstrated that TX14A stimulates cell proliferation/survival, migration, and invasion, and activates the Raf-MEK-ERK-RSK-Elk-1 signaling cascade of the MAPK pathway.

CONCLUSIONS

These results are suggestive of a potential pleuripotent regulatory function for prosaposin in prostate cancer.

C-peptide induces chemotaxis of human CD4-positive cells: involvement of pertussis toxin-sensitive G-proteins and phosphoinositide 3-kinase

Increased levels of C-peptide, a cleavage product of proinsulin, circulate in patients with insulin resistance and early type 2 diabetes, a high-risk population for the development of a diffuse and extensive pattern of arteriosclerosis. The present study examined the effect of C-peptide on CD4(+) lymphocyte migration, an important process in early atherogenesis. C-peptide stimulated CD4(+) cell chemotaxis in a concentration-dependent manner. This process involves pertussis toxin-sensitive G-proteins as well as activation of phosphoinositide 3-kinase (PI 3-K). Biochemical analysis showed that C-peptide induced recruitment of PI 3-K to the cell membrane as well as PI 3-K activation in human CD4(+) cells. In addition, antidiabetic peroxisome proliferator-activated receptor gamma-activating thiazolidinediones inhibited C-peptide-induced CD4(+) cell chemotaxis as well as PI 3-Kgamma activation. Finally, immunofluorescence staining of thoracic artery specimen of diabetic patients showed intimal CD4(+) cells in areas with C-peptide deposition. Thus, C-peptide might deposit in the arterial intima in diabetic patients during early atherogenesis and subsequently attract CD4(+) cells to migrate into the vessel wall.

Morphologic Findings of Coronary Atherosclerotic Plaques in Diabetics

OBJECTIVE

Coronary atherosclerotic plaque composition of diabetic subjects and localization of receptor for advanced glycation end products (RAGE) and its ligands have not been extensively studied.

METHODS AND RESULTS

Hearts from diabetic subjects and age, race, and sex-matched nondiabetic subjects dying suddenly were examined. Coronary arteries were dissected and lesions were evaluated for plaque burden, necrotic core size, and inflammatory infiltrate. The expression of RAGE, the RAGE-binding protein (S100-A12, EN-RAGE), and cell death (apoptosis) were also determined. Lesions from type II diabetic subjects had larger mean necrotic cores (P=0.01) and greater total and distal plaque load (P<0.001) than nondiabetic subjects. Necrotic core size correlated positively with diabetic status, independent of other risk factors. Intimal staining for macrophages, T-cells, and HLA-DR was also significantly greater in diabetic subjects (P=0.03, P=0.003, and P<0.0001), respectively. The association of increased macrophage infiltrate was independent of cholesterol levels and patient age. Expression of RAGE and EN-RAGE was significantly greater in diabetic subjects (P=0.004) and was associated with apoptotic smooth muscle cells and macrophages.

CONCLUSIONS

In sudden coronary death, inflammation and necrotic core size play a greater role in the progression of atherosclerosis in diabetic subjects. The expression of RAGE and EN-RAGE may further compromise cell survival and promote plaque destabilization.

C-Peptide Colocalizes with Macrophages in Early Arteriosclerotic Lesions of Diabetic Subjects and Induces Monocyte Chemotaxis In Vitro

Objective— Increased levels of C-peptide, a cleavage product of proinsulin, circulate in patients with insulin resistance and early type 2 diabetes, a high-risk population for the development of a diffuse and extensive pattern of arteriosclerosis. This study tested the hypothesis that C-peptide might participate in atherogenesis in these patients.

Method and Results— We demonstrate significantly higher intimal C-peptide deposition in thoracic artery specimens from young diabetic subjects compared with matched nondiabetic controls as determined by immunohistochemical staining. C-peptide colocalized with monocytes/macrophages in the arterial intima of artery specimen from diabetic subjects. In vitro, C-peptide stimulated monocyte chemotaxis in a concentration-dependent manner with a maximal 2.3±0.4-fold increase at 1 nmol/L C-peptide. Pertussis toxin, wortmannin, and LY294002 inhibited C-peptide–induced monocyte chemotaxis, suggesting the involvement of pertussis toxin-sensitive G-proteins as well as a phosphoinositide 3-kinase (PI3K)-dependent mechanism. In addition, C-peptide treatment activated PI3K in human monocytes, as demonstrated by PI3K activity assays.

Conclusion— C-peptide accumulated in the vessel wall in early atherogenesis in diabetic subjects and may promote monocyte migration into developing lesions. These data support the hypothesis that C-peptide may play an active role in atherogenesis in diabetic patients and suggest a new mechanism for accelerated arterial disease in diabetes.

Muscular dysfunction elicited by creep of lumbar viscoelastic tissue

The biomechanics, histology and electromyography of the lumbar viscoelastic tissues and multifidus muscles of the in vivo feline were investigated during 20 min of static as well as cyclic flexion under load control and during 7 h of rest following the flexion. It was shown that the creep developed in the viscoelastic tissues during the 20 min of static or cyclic flexion did not fully recover over the 7 h of following rest. It was further seen that a neuromuscular disorder with five distinct components developed during and after the static and cyclic flexion. The neuromuscular disorder consisted of a decreasing magnitude of reflexive EMG from the multifidus upon flexion as well as of superimposed spasms. The recovery period was characterized by an initial muscle hyperexcitability, a slowly increasing reflexive EMG and a delayed hyperexcitability. Histological data from the supraspinous ligament demonstrate significant increase (x 10) in neutrophil density in the ligament 2 h into the recovery and even larger increase (x 100) 6 h into the recovery from the 20 min flexion, indicating an acute soft tissue inflammation. It was concluded that sustained static or cyclic loading of lumbar viscoelastic tissues may cause micro-damage in the collagen structure, which in turn reflexively elicit spasms in the multifidus as well as hyperexcitability early in the recovery when the majority of the creep recovers. The micro-damage, however, results in the time dependent development of inflammation. In all cases, the spasms, initial and delayed hyperexcitabilities represent increased muscular forces applied across the intervertebral joints in an attempt to limit the range of motion and unload the viscoelastic tissues in order to prevent further damage and to promote healing. It is suggested that a significant insight is gained as to the development and implications of a common idiopathic low back disorder as well as to the development of cumulative trauma disorders.

Expanding expression of the 5-lipoxygenase pathway within the arterial wall during human atherogenesis

Oxidation products of low-density lipoproteins have been suggested to promote inflammation during atherogenesis, and reticulocyte-type 15-lipoxygenase has been implicated to mediate this oxidation. In addition, the 5-lipoxygenase cascade leads to formation of leukotrienes, which exhibit strong proinflammatory activities in cardiovascular tissues. Here, we studied both lipoxygenase pathways in human atherosclerosis. The 5-lipoxygenase pathway was abundantly expressed in arterial walls of patients afflicted with various lesion stages of atherosclerosis of the aorta and of coronary and carotid arteries. 5-lipoxygenase localized to macrophages, dendritic cells, foam cells, mast cells, and neutrophilic granulocytes, and the number of 5-lipoxygenase expressing cells markedly increased in advanced lesions. By contrast, reticulocyte-type 15-lipoxygenase was expressed at levels that were several orders of magnitude lower than 5-lipoxygenase in both normal and diseased arteries, and its expression could not be related to lesion pathology. Our data support a model of atherogenesis in which 5-lipoxygenase cascade-dependent inflammatory circuits consisting of several leukocyte lineages and arterial wall cells evolve within the blood vessel wall during critical stages of lesion development. They raise the possibility that antileukotriene drugs may be an effective treatment regimen in late-stage disease.

Increased serum homocysteine and sudden death resulting from coronary atherosclerosis with fibrous plaques

INTRODUCTION

Modest elevations of total homocysteine have been associated with increased risk for coronary atherosclerosis but correlation between elevated homocysteine and plaque morphology has not been described in humans.

METHODS

We determined serum homocysteine at postmortem from 87 men with coronary thrombus (62 of whom were diagnosed as acute), from 35 men with severe coronary disease without thrombus, and from 46 controls. In coronary deaths, atherosclerotic plaques at the sites of maximal luminal narrowing of the four epicardial coronary arteries were classified as fibrous plaques, fibrous cap atheromas, thin-cap atheromas, and healed ruptures, and macrophage infiltration was assessed semiquantitatively.

RESULTS

Median serum homocysteine postmortem as a result of acute thrombus was 10.4 micro mol/L (P=0.4 versus controls), 12.1 micro mol/L in men with organized thrombi (P=0.1 versus controls), 15.6 micro mol/L in men without thrombus (P=0.007 versus controls), and 9.8 micro mol/L in controls. The median homocysteine was 12.1 micro mol/L in 65 men with healed infarcts (P=0.03 versus controls). The number of fibrous plaques was associated with log-normalized homocysteine (P=0.004), independent of age, albumin, smoking, hypertension, and serum cholesterol. Homocysteine levels in the upper tertile (>15 micromol/L) were associated with sudden death without acute or organized thrombus (odds ratio 3.8, P=0.03) independent of age and other risk factors; the coexistence of diabetes increased the association (odds ratio 25.1, P=0.009, versus lowest tertile < or =8.5 micromol/L).

CONCLUSIONS

Increased serum homocysteine is associated with sudden death in the absence of acute coronary thrombosis, especially with concomitant diabetes, and with the presence of lipid-poor, fibrous plaques.

Elevated C-reactive protein values and atherosclerosis in sudden coronary death: association with different pathologies

BACKGROUND

Elevations in serum C-reactive protein measured by high-sensitivity assay (hs-CRP) have been associated with unstable coronary syndromes. There have been no autopsy studies correlating hs-CRP to fatal coronary artery disease.

METHODS AND RESULTS

Postmortem sera from 302 autopsies of men and women without inflammatory conditions other than atherosclerosis were assayed for hs-CRP. There were 73 sudden deaths attributable to atherothrombi, 71 sudden coronary deaths with stable plaque, and 158 control cases (unnatural sudden deaths and noncardiac natural deaths without conditions known to elevate CRP). Atherothrombi were classified as plaque ruptures (n=55) and plaque erosion (n=18); plaque burden was estimated in each heart. Total cholesterol, high-density lipoprotein cholesterol, diabetes, smoking history, and body mass index were also determined. Immunohistochemical stains for CRP and numbers of thin cap atheromas per heart were quantitated in coronary deaths with hs-CRP in the highest and lowest quintiles. The median hs-CRP was 3.2 microg/mL in acute rupture, 2.9 microg/mL in plaque erosion, 2.5 microg/mL in stable plaque, and 1.4 microg/mL in controls. Mean log hs-CRP was higher in rupture (P<0.0001), erosion (P=0.005), and stable plaque (P=0.0003) versus controls. By multivariate analysis, atherothrombi (P=0.02), stable plaque (P=0.003), and plaque burden (P=0.03) were associated with log hs-CRP independent of age, sex, smoking, and body mass index. Mean staining intensity for CRP of macrophages and lipid core in plaques was significantly greater in cases with high hs-CRP than those with low CRP (P=0.0001), as were mean numbers of thin cap atheromas (P<0.0001).

CONCLUSIONS

hs-CRP is significantly elevated in patients dying suddenly with severe coronary artery disease, both with and without acute coronary thrombosis, and correlates with immunohistochemical staining intensity and numbers of thin cap atheroma.

Traditional risk factors and the incidence of sudden coronary death with and without coronary thrombosis in blacks

BACKGROUND

Blacks have a high rate of sudden coronary death (SCD). We determined the rate of SCD in men and women 30 to 69 years of age in a 6-year period recorded at a state Medical Examiner's Office.

METHODS AND RESULTS

In a subset of 327 whites and 130 blacks, hearts were systematically studied to determine the extent of coronary disease, presence and type of thrombus (acute rupture, acute erosion, stable plaque), and heart weight. These parameters were correlated with the presence of conventional risk factors. The estimated rate of SCD in blacks was similar to that in whites under the age of 40 years but increased compared with whites with advancing age, becoming 1.5 times the rate for whites in the 7th decade (95% of the increase in the 6th decade was due to sudden death with stable plaque). Among the autopsied group with severe coronary atherosclerosis, HDL cholesterol was higher and hypertension more prevalent in blacks, but there was no difference in the prevalence of healed infarcts, plaque burden, heart weight, acute thrombi, or rates of diabetes, cigarette smoking, and total cholesterol.

CONCLUSIONS

When compared with a control autopsy group of 568 deaths, multivariate analysis showed a significant association in blacks between stable plaque and left ventricular hypertrophy (risk ratio, 7.6), type 1 diabetes (risk ratio, 3.6), hypertension (risk ratio, 3.5), elevated total cholesterol (risk ratio, 3.1) and type 2 diabetes (risk ratio, 2.9). Because these risk factors are associated with SCD in blacks, they may be important targets for reducing the disparately high rate of SCD in blacks as compared with whites.

The effect of placing a tensioned graft across open growth plates. A gross and histologic analysis

BACKGROUND

Midsubstance tears of the anterior cruciate ligament in skeletally immature patients are increasingly common and are a challenging problem. The results of nonoperative treatment are no better in children than they are in adults. Physeal-sparing reconstructive procedures have yielded poor results. Reconstructive procedures that are utilized in adults violate the physis, potentially resulting in growth abnormalities. The objective of this study was to provide a model for reconstruction of the anterior cruciate ligament in skeletally immature patients by evaluating the effects of a tensioned connective-tissue graft placed across the canine physis.

METHODS

Twelve ten-week-old beagles underwent reconstruction of the anterior cruciate ligament consisting of placement of fascia lata autograft through drill-holes across the femoral and tibial physes, tensioning of the graft to 80 N, and fixing it with screws and washers. The contralateral limb served as a control. One dog was eliminated from the study secondary to a postoperative infection. Four months postoperatively, the dogs were killed and were inspected grossly, radiographically, and histologically for any evidence of growth disturbance.

RESULTS

Significant valgus deformity of the distal part of the femur (p < 0.001) and significant varus deformity of the proximal part of the tibia (p = 0.03) developed in the treated limbs. Neither radiographic nor histologic examination demonstrated any evidence of physeal bar formation.

CONCLUSIONS

Significant growth disturbances occur with excessively tensioned transphyseal reconstruction of the anterior cruciate ligament in the canine model. These growth disturbances occur without radiographic or histologic evidence of physeal bar formation.

Effect of intraarticular stainless steel implants on the health of the rabbit knee joint: an experimental study

OBJECTIVE

This study was designed to investigate the histologic changes to the knee joints of rabbits after insertion of a metal implant in retrograde fashion.

DESIGN

Eighteen rabbits had a modified stainless steel screw implanted in one knee, with the other knee serving as a sham-operated control. The animals were killed after two, six, or twelve months.

OUTCOME MEASURES

The histologic status of the cartilage and synovium were graded by the Modified Mankin and Mirra criteria, respectively.

RESULTS

At the time of killing, every insertion site was covered by fibrous tissue. Statistical analysis showed no significant differences in histologic scores between implanted and control knees.

CONCLUSIONS

Insertion of a stable, well-fixed implant results in no deleterious effect to the knee joint.

The distribution of oxidatively-modified lysine in the human vasculature

Fifty-seven sections of human vessels, collected in the Pathobiological Determinants of Atherosclerosis in Youth study from individuals aged 25-34, were stained with two monoclonal antibodies to oxidatively-modified lysine. Intensity and extent of immunoreactivity were graded by three pathologists. Aorta from a Watanabe heritable hyperlipidemic (WHHL) rabbit was stained as a positive control. Intimal immunoreactivity in the rabbit was predominantly localized to lesions. Although immunoreactivity in humans was somewhat more intense in atherosclerotic plaques, substantial staining was present in intima with diffuse intimal thickening and coronary veins. Localization of oxidatively-modified lysine in humans did not correlate with localization or severity of atherosclerosis. Localization of immunoreactivity for oxidatively-modified lysine to intimal lesions in the WHHL rabbit may be due to absence of diffuse intimal thickening, which prevents retention of epitopes throughout the intima.

IL-17 Stimulates Granulopoiesis in Mice: Use of an Alternate, Novel Gene Therapy-Derived Method for In Vivo Evaluation of Cytokines

IL-17 is a novel cytokine secreted principally by CD4+ T cells. It has been shown to support the growth of hemopoietic progenitors in vitro; however, its in vivo effects are presently unknown. Adenovirus-mediated gene transfer of the murine IL-17 cDNA targeted to the liver (5 × 109 plaque-forming units (PFU) intravenous) resulted in a transiently transgenic phenotype, with dramatic effects on in vivo granulopoiesis. Initially, there was a significant increase (fivefold) in the peripheral white blood count (WBC), including a 10-fold rise in the absolute neutrophil count. This was associated with a doubling in the spleen size over 7–14 days after gene transfer, which returned to near baseline by day 21, although the white blood cell count remained elevated. There was a profound stimulation of splenic hemopoiesis as demonstrated by an increase in total cellularity by 50% 7 days after gene transfer and an increase in hemopoietic colony formation. A maximal increase in frequency of high proliferative potential colonies (HPPC) (11-fold) and CFU-granulocyte-macrophage (GM) and CFU-granulocyte-erythrocyte-megakaryocyte-monocyte (GEMM) (CFU) (6-fold) was seen on day 3 after IL-17 gene transfer. Both CFU and HPPC remained significantly elevated in the spleen throughout day 21, but at reduced levels compared with day 3. Bone marrow CFU and HPPC were elevated on day 3 only by 75% and 25%, respectively, without changes in total cellularity. Thus, murine IL-17 is a cytokine that can stimulate granulopoiesis in vivo. Since IL-17 is principally produced by CD4+ T cells, this cytokine could have therapeutic implications in AIDS-related bone marrow failure and opportunistic infections.

IL-17 stimulates granulopoiesis in mice: use of an alternate, novel gene therapy-derived method for in vivo evaluation of cytokines

IL-17 is a novel cytokine secreted principally by CD4+ T cells. It has been shown to support the growth of hemopoietic progenitors in vitro; however, its in vivo effects are presently unknown. Adenovirus-mediated gene transfer of the murine IL-17 cDNA targeted to the liver (5 x 10(9) plaque-forming units (PFU) intravenous) resulted in a transiently transgenic phenotype, with dramatic effects on in vivo granulopoiesis. Initially, there was a significant increase (fivefold) in the peripheral white blood count (WBC), including a 10-fold rise in the absolute neutrophil count. This was associated with a doubling in the spleen size over 7-14 days after gene transfer, which returned to near baseline by day 21, although the white blood cell count remained elevated. There was a profound stimulation of splenic hemopoiesis as demonstrated by an increase in total cellularity by 50% 7 days after gene transfer and an increase in hemopoietic colony formation. A maximal increase in frequency of high proliferative potential colonies (HPPC) (11-fold) and CFU-granulocyte-macrophage (GM) and CFU-granulocyte-erythrocyte-megakaryocyte-monocyte (GEMM) (CFU) (6-fold) was seen on day 3 after IL-17 gene transfer. Both CFU and HPPC remained significantly elevated in the spleen throughout day 21, but at reduced levels compared with day 3. Bone marrow CFU and HPPC were elevated on day 3 only by 75% and 25%, respectively, without changes in total cellularity. Thus, murine IL-17 is a cytokine that can stimulate granulopoiesis in vivo. Since IL-17 is principally produced by CD4+ T cells, this cytokine could have therapeutic implications in AIDS-related bone marrow failure and opportunistic infections.

Successful resection of multifocal hepatic adenoma during pregnancy

Hepatic adenoma is an unusual complication of pregnancy. Most of these lesions are solitary and associated with hormonal contraceptives. We believe ours is the first case of successful resection of multifocal hepatic adenoma during pregnancy in a patient with no history of oral contraceptive use.