A Short-Term In Vivo Evaluation of the Istanbul Heart Left Ventricular Assist Device in a Pig Model.

OBJECTIVES: A continuous-flow centrifugal blood pump system has been recently developed as an implantable left ventricular assist device for patients with endstage heart failure. The objective of this study was to evaluate the initial in vivo performance of a newly developed left ventricular assist device (iHeart or Istanbul heart; Manufacturing and Automation Research Center, Koc University, Istanbul, Turkey) in an acute setting using a pig model. MATERIALS AND METHODS: Three pigs (77, 83, 92 kg) received implants via a median sternotomy, with animals supported for up to 6 hours. An outflow cannula was anastomosed to the ascending aorta. Anticoagulation was applied by intravenous heparin administration. During the support period, pump performance was evaluated under several flow and operating conditions. All pigs were humanely sacrificied after the experiments, and organs were examined macroscopically and histopathologically. RESULTS: Flow rate ranged between 1.5 and 3.6 L/min with pump speeds of 1500 to 2800 revolutions/min and motor current of 0.6 to 1.3 A. Initial findings confirmed thatthe iHeart ventricular assist device had sufficient hydraulic performance to support the circulation. During the experimental period, plasma free hemoglobin levels were found to be within normalranges.Thrombus formation was not observed inside the pump in all experiments. CONCLUSIONS: The iHeart ventricular assist device demonstrated encouraging hemodynamic performance and good biocompatibility in the pig model for use as an implantable left ventricular assist device. Further acute in vivo studies will evaluate the short-term pump performance prior to chronic studies for long-term evaluation.

Loss-of-Function Mutations in ELMO2 Cause Intraosseous Vascular Malformation by Impeding RAC1 Signaling.

Vascular malformations are non-neoplastic expansions of blood vessels that arise due to errors during angiogenesis. They are a heterogeneous group of sporadic or inherited vascular disorders characterized by localized lesions of arteriovenous, capillary, or lymphatic origin. Vascular malformations that occur inside bone tissue are rare. Herein, we report loss-of-function mutations in ELMO2 (which translates extracellular signals into cellular movements) that are causative for autosomal-recessive intraosseous vascular malformation (VMOS) in five different families. Individuals with VMOS suffer from life-threatening progressive expansion of the jaw, craniofacial, and other intramembranous bones caused by malformed blood vessels that lack a mature vascular smooth muscle layer. Analysis of primary fibroblasts from an affected individual showed that absence of ELMO2 correlated with a significant downregulation of binding partner DOCK1, resulting in deficient RAC1-dependent cell migration. Unexpectedly, elmo2-knockout zebrafish appeared phenotypically normal, suggesting that there might be human-specific ELMO2 requirements in bone vasculature homeostasis or genetic compensation by related genes. Comparative phylogenetic analysis indicated that elmo2 originated upon the appearance of intramembranous bones and the jaw in ancestral vertebrates, implying that elmo2 might have been involved in the evolution of these novel traits. The present findings highlight the necessity of ELMO2 for maintaining vascular integrity, specifically in intramembranous bones.

Epitheloid hemangioendothelioma of the palpebral lobe of the lacrimal gland.

PURPOSE: To describe a case of an epitheloid hemangioendothelioma which is a tumor of endothelial origin with borderline malignancy between hemangioma and angiosarcoma and which is very rare in the orbit. METHODS: Clinical features, results of imaging and histopathological studies and postoperative clinical course of a 22-year-old female patient who presented with a gradual swelling of the left upper eyelid were reviewed. RESULTS: Magnetic resonance imaging studies suggested a solid lesion with moderate contrast enhancement in the palpebral lobe of the lacrimal gland. A short course of systemic corticosteroid therapy failed to resolve the lesion. Excisional biopsy of the tumor yielded the diagnosis of epitheloid hemangioendothelioma of the lacrimal gland. The tumor was composed of nests of epitheloid cells, some forming CD31 positive intracytoplasmic vascular channels containing erythrocytes. CD34 and EMA were also positive and desmin, SMA, p63, S100, Factor VIII and HHV-8 were negative on immunohistochemical studies. During 44 months of follow-up, there has been no recurrence or systemic metastasis. CONCLUSION: Epitheloid hemangioendothelioma can occur in the palpebral lobe of the lacrimal gland as a hard, painless, immobile mass. Simple excisional biopsy of the tumor, assumed to have an intermediate malignancy grade, without further local or systemic therapy provided a disease-free 3-year survival.

Morphological and immunohistochemical features of malignant vascular tumors with special emphasis on GLUT1, and FKBP12 expressions.

OBJECTIVE: Angiosarcomas and hemangioendotheliomas are rare malignant vascular neoplasms (MVTs). Here, we reviewed the clinicomorphological characteristics of 27 MVTs with the implementation of two novel immunohistochemical markers: GLUT1, and FKBP12. MATERIAL AND METHOD: MVTs, except for Kaposi's sarcoma, were retrieved from the archive and reviewed. Tumor size, the presence of hemorrhage and necrosis, growth pattern, cellularity, cellular characteristics and mitotic activity were recorded as morphological variables. Immunohistochemically, CD34, CD31, GLUT1, FKBP12, Mdm2, p53, c-kit, and CD99 were applied. Clinical information was gathered from hospital records and computer-based patient data systems. RESULTS: The median age was 53 years (range 16-77). Extremities (37%) were the most common primary site followed by the head and neck. Five of 16 (31%) low grade and 7 of 11 (64%) high grade tumors were metastasized to varying organs, mainly the liver and lungs. The median survival was 49 months. Ninety percent of high grade tumors were larger than 3 cm. Hemorrhage and necrosis were seen in 85% and 41% of cases, respectively. Nuclear pleomorphism, cellularity and mitotic activity were higher in high grade tumors than in low grade ones (p < 0.0001). While 68% of the cases expressed CD34, 81% of them were positive with CD31. All cases except one low grade tumor were strongly and diffusely stained with FKBP12. Significant GLUT1 expression was observed in 23% of cases, especially in areas showing epithelioid morphology. Either Mdm2 or p53 was positive in over one third of the tumors. CONCLUSION: The studied markers were not able to distinguish between low and high grade MVTs. FKBP12 may take a role in the diagnostic panel of MVTs. GLUT1 expression, previously proposed for the diagnosis of infantile hemangioma, should be assessed carefully since almost one quarter of MVTs were also GLUT1 positive.

Xanthogranulomatous cystitis: a challenging imitator of bladder cancer.

Xanthogranulomatous cystitis is a rare, benign, chronic inflammatory disease of the bladder, mimicking malignancy with unknown etiology. Herein, we report a 57-year-old man who presented with pollakiuria, nocturia, dysuria, left flank pain, and a palpable mass on the right lower abdomen. Computerized tomography demonstrated an obstructing 10-mm stone in the lower third of the left ureter and a 6-cm solid mass on the right at the anterolateral wall of the bladder. The mass presented local perivesical invasion at the anterolateral side. Cystouretroscopy revealed a mass protruding into the bladder cavity with edematous smooth surface. Frozen section analysis of the partial cystectomy specimen could not rule out malignancy. Therefore, radical cystoprostatectomy and ureterolithotomy were performed. Histologically, fibrosis, numerous plasma cells, eosinophils, and, immunohistochemically, CD68-positive epithelioid and foamy macrophages were detected. Localized prostatic adenocarcinoma was also found. The present case of xanthogranulomatous cystitis is the 23rd to be reported in the world literature.

Congenital solid thigh mass: a report of nonself healing form of langerhans cell histiocytosis.

SUMMARY: Langerhans cell histiocytosis (LCH) is very rarely seen in the pediatric age group. Self-healing is the usual clinical course in congenital LCH with cutaneous involvement. We describe a newborn with a solid mass in his thigh noticed at birth, without skin manifestations. LCH should be considered in the differential diagnosis of congenital solid masses.

Amyloidoma of the temporal bone and upper cervical spine; presentation of a rare clinical entity with a brief literature review.

The amyloidoses comprise a heterogeneous group of diseases characterized by the extracellular deposition of an insoluble protein complex in various tissues. Amyloidomas in bone are most common in patients with systemic amyloidosis and plasma cell dyscrasias. Decreased clearance of beta2 microglobulin frequently causes excessive amyloid deposition in the musculoskeletal system in patients with a history of chronic renal failure and long-term dialysis treatment. Calvarial and/or upper cervical amyloid depositions are rarely seen in clinical practice; therefore the diagnosis requires high index of suspicion and special staining of the tissue. In this article, we present a patient with amyloidoma at the right temporal bone and upper cervical spine. The etiology, radiological findings and differential diagnosis were briefly discussed in the highlights of relevant literature. Amyloidomas should be particularly kept in mind in patients with a history of long-term dialysis therapy, plasma cell dyscrasias or long-standing inflammatory diseases. Differential diagnosis mostly encounters benign or malign mesenchymal neoplasms of the dura and skull base, metastatic tumors, plasmacytoma and brown tumor in the calvarium, as well as primary osseous tumors or metastatic lesions in the spine.

Intravascular lymphoma masquerading as multiembolic stroke developing after coronary artery by-pass surgery.

BACKGROUND: Intravascular lymphoma (IVL) is a very rare non-Hodgkin type lymphoproliferative disorder characterized by neoplastic growth of lymphoid cells within the lumen of capillaries, small veins, and arterioles. The neoplastic cells cannot reach the parenchyma because of the loss of adhesion molecules during malignant transformation. Multifocal vascular occlusions caused by proliferation of malignant lymphocytes in the lumen result in diffuse thrombosis and tissue infarction. The clinical symptoms of the disease are dependent on the specific organ involvement which most often includes the central nervous system and skin. Neurologic presentation includes focal sensory or motor deficits, altered sensorium, rapidly progressive dementia, seizures, ataxia, and vertigo. CASE REPORT: We report a patient with IVL whose symptoms developed on the second postoperative day of coronary artery-bypass surgery imitating a multiembolic stroke. Magnetic resonance imaging showed widespread ischemic subcortical lesions. The patient's clinical status worsened irrespective of supportive medical treatment. The diagnosis was established by autopsy. CONCLUSION: IVL may mimic ischemic stroke. IVL is not often diagnosed before death because of the intravascular growth pattern of the tumor cells and a fulminant clinical course. IVL may be considered in the differential diagnosis of ischemic stroke patients with progressive worsening despite medical management.

Dorsal root ganglionectomy for pseudotumor of the L3 dorsal root ganglion: a rare case and a rare treatment.

Dorsal root ganglia are oval enlargements on the dorsal nerve roots and contain the cell bodies of sensory neurons. Asymmetry of dorsal root ganglia may occur naturally, yet natural occurrence of gigantic dorsal root ganglion (DRG) is rare. The patient was 61-year-old woman who presented with atypical symptoms like neuropathic pain and urinary distention. Neuroimaging has shown left L3-4 far-lateral disc herniation and a gigantic L3 DRG. At surgery, the dural sheath of the ganglion had to be opened and a firm, yellow-colored abnormal tissue was exposed. The abnormal tissue considered to be a tumor of neural origin was gross totally excised and the patient's symptoms ceased immediately after surgery. Histopathological examination of the specimen revealed nothing more than normal DRG morphology. At 4 months postoperatively, the patient is well with mild L3 hyperesthesia and hyperalgesia. Dural sheath opening in neurosurgery is not a routine practice. The sheath may need to be opened when surgeon suspects of a tumor, a free disc fragment and any inflammation within the ganglion. Operative morphology of a severely edematous but non-tumoral (pseudotumor) ganglion has not previously been documented.

Diethylstilbestrol-induced prolactinoma: dose-related tumor growth and effect of catecholaminergic cells on prolactin tumor cells.

BACKGROUND: Prolactinoma is a pituitary adenoma originating from prolactin-secreting epithelial cells of the adenohypophysis. Unfortunately, there appears to be a relatively high recurrence rate despite all pharmacological, radiological, and surgical therapeutic interventions. The aim of the present study was to evaluate the extent of involvement of the dopaminergic dysregulation hypothesis of prolactinomas. We transplanted, in rats, DES-induced prolactinoma cells into the adrenal medulla or under the renal capsule, two tissues rich and poor in catecholaminergic innervation, respectively. METHODS: Prolactinoma was dose-dependently induced in ovariectomized female rats implanted with 10 and 20 mg DES, and tumor cells taken from prolactinoma induced by 20 mg DES were either transplanted under the renal capsule or into the adrenal medulla. RESULTS: Although the adrenal medulla, with its high dopamine content to inhibit prolactin secretion, was devoid of any tumoral development, a significant tumoral development was evident under the renal capsule, seemingly because of no inhibitory control over prolactin secretion coexisting with the dopamine deficiency of the tissue. Results are discussed for an alternatively possible regression and prevention of any relapse of prolactinoma, most possibly occurring because of tuberoinfundibular dopamine deficiency, by the implantation of another dopamine-rich tissue beside the tumoral mass. CONCLUSION: Regression and prevention of any relapse of a tumoral outgrowth, most possibly occurring because of tuberoinfundibular dopamine deficiency, can well be alternatively achieved by the implantation of another dopamine-rich tissue beside the tumoral mass prolactinoma.

PTEN and p27 expression in mature T-cell and NK-cell neoplasms.

PTEN is a tumor suppressor gene located on chromosome 10q23 and is amongst the most commonly mutated genes in human cancers. The lipid phosphatase activity of Pten enables it to dephosphorylate PIP3, thereby antagonizing growth factor stimulated PI3-kinase signaling mediated by AKT/PKB. The growth inhibition effect of PTEN has been shown to be mediated by p27 which is one of the important effector molecules downstream of the AKT pathway. Recently the importance of the Pten and AKT pathway in the regulation of the immune system and development of hematological malignancies has been shown. Loss of Pten and p27 expressions were examined immunohistochemically in 45 patients with peripheral T- and NK-cell lymphoma. Partial or complete loss of Pten was detected in 66.7% of the cases of anaplastic large cell lymphoma (ALCL) compared to only 12.5% of all other mature T-/NK-cell lymphomas combined. Loss of p27 was identified in 64.9% of cases, which showed a positive correlation with Pten loss. In this study, we showed that loss of Pten is more frequent in ALCL as compared to other mature T-/NK-cell lymphomas, which strongly correlates with the loss of p27 expression. Our findings provide further evidence for the importance of the deregulation of the PI3K-AKT pathway in ALCL.

Solvent-dehydrated calvarial allografts in craniofacial surgery.

Craniofacial surgery almost always requires the use of bone grafting. Although autografts are the standard procedure for bone grafting, it is sometimes not possible to harvest bone, and autografts have particular risks. The use of allograft bone provides a reasonable alternative to meet the need for graft material. Solvent dehydration is a multistage procedure in which human cadaveric bone is processed by osmotic exchange baths and gamma sterilization. This processing avoids the risk of infection transmission, decreases antigenicity, and does not weaken the mechanical properties of the bone. Solvent-dehydrated, gamma-irradiated human calvarial bone allografts were used for reconstruction of craniofacial deformities in 24 patients between 1988 and 2002. Resorption of the allografts and results of the surgical intervention were evaluated with plain radiographs and three-dimensional computed tomography 12 months after surgery, in 21 patients. Serologic tests for human immunodeficiency virus-1 antibody, hepatitis B surface antigen, and hepatitis C antigen were also performed. Biopsy specimens were taken from the allografts. Average follow-up in this group was 30 months (range, 8 to 60 months), and results of serologic tests were negative in all patients. Seventy-one percent of the patients (15 of 21) showed no resorption, with partial and complete allograft fusion. One patient had nearly total graft loss and the remaining five patients had 10 to 25 percent graft resorption. Rigid fixation of the allograft, contact with the dura and periosteum, and prevention of dead spaces around the allograft are the most important factors in achieving a satisfactory result. In solvent-dehydrated bone allografts, sterilization and antigenic tissue cleaning are achieved after several steps with a minimal dose of radiation. The result is a nonantigenic, sterile mechanical scaffold that can tolerate external forces. Although autografts are the standard in craniofacial surgery, solvent-dehydrated calvarial bone allografts produced successful results in selected cases.

Treatment results and prognostic factors in Ewing sarcoma.

Files of 133 children with Ewing sarcoma (median age 10 years) were reviewed. Frequent primary sites were extremities, trunk, pelvis, and cranium. Half of 43 patients with metastases had disease in the lungs. Ten-year overall and event-free survival rates were 31% and 19%, respectively. Five-year overall survival rates were 42% in localized and 15% in metastatic disease (p < .0001); 66% in cases with primary tumors < 8 cm and 29% in larger tumors (p = .013). VAC (vincristine, actinomycin D, and cyclophosphamide) regimens with anthracyclines resulted in better survival. Presence of distant metastases, large primary tumors, and pelvic localization were related to poor prognosis. Novel therapeutic approaches are needed to produce better results, especially in high-risk patients.

Biological reactions to a poly(L-lactide)-hydroxyapatite composite: a study in canine mandible.

In this study, bone response, possible use and ultimate fate of a chemically-synthesized poly(L-lactide)-hydroxyapatite (PLLA-HA) composite was experimented in canine mandible. Bilateral mandibular second premolars were extracted in four dogs. The PLLA-HA composite was placed into left surgical sites, and right extraction sites were used as controls. After three months of healing, bone specimens were harvested from each animal and processed for histological evaluation. Bone uptake of methylene diphosphonate (99mTc-MDP) was calculated as indicators of osteoblastic activity in the surgical sites. Histological evaluation and the amount of 99mTc-MDP uptake showed that all surgical sites had similar levels of cellular activity and the material was biocompatible. The experimental PLLA-HA composite studied is safe to be used as a small-defect filler in applications such as repair of alveolar defects, ridge augmentations, and sinus lift procedures.

Analysis of in situ proliferative activity in oral gingival epithelium in patients with xerostomia.

BACKGROUND: Sjögren's syndrome is an autoimmune disease characterized by xerostomia and keratoconjunctivitis sicca. The relationship between xero-stomia and proliferative activity in human gingival epithelium is not known. Proliferating cell nuclear antigen (PCNA) is a nuclear protein associated with the cell cycle. Nuclear PCNA immunoreactivity is found in the proliferative compartment of normal tissues. The aims of this study were to evaluate PCNA expression in oral gingival epithelium of healthy and inflamed gingiva obtained from patients with Sjögren's syndrome, and to compare the results to age- and gender-matched subjects with normal salivary function. METHODS: Eighteen Sjögren's syndrome patients and 28 controls (14 with chronic periodontitis and 14 with no clinical evidence of periodontal disease) were included in the study. Biopsies were obtained from both inflamed and healthy gingiva. The expression of PCNA was evaluated in formalin-fixed, paraffin-embedded gingival samples using an immunoperoxidase technique and PC10 monoclonal antibody to PCNA. RESULTS: PCNA expression was observed both in the basal and suprabasal layers, and was found to be more prominent in the suprabasal layers. Proliferative index (PI) in inflamed gingiva was significantly lower in the Sjögren's syndrome group. However, no significant difference was observed between the study and control groups with respect to PI in healthy gingiva. In both groups, PI was found to be increased due to inflammation. CONCLUSIONS: Our data indicate that proliferative activity is observed in the suprabasal layers and, less frequently, in the basal layer. Inflammation caused increased proliferative activity. However, this positive effect of inflammation on epithelial cell proliferation decreased significantly with a lack of saliva. Therefore, it appears that saliva-derived biological mediators may also contribute to increased proliferative activity observed during inflammation.

Dihydropyrimidine dehydrogenase enzyme deficiency: clinical and genetic assessment of prevalence in Turkish cancer patients.

BACKGROUND: Fluorouracil has been reported to induce severe side-effects in particular subjects who have deficiency in dehydropyrimidine dehyrogenase activity, the major enzyme in the catabolism of fluorouracil. PATIENTS AND METHODS: In this study, we aimed to analyze the heterozygote and homozygote frequencies of dehydropyrimidine dehyrogenase gene mutation in 200 patients receiving fluorouracil based chemotherapy together with the assessment of the toxicity profile of these chemotherapy regimens. RESULTS: According to the results of clinical toxicity assessments, grade 3-4 hematologic toxicity was noted in 12% of the patients. Grade 3 gastrointestinal toxicity was present in 5% of the subjects with no grade 4 side effects. The heterozygote (2q(1-q)) and homozygote (q2) frequencies of dehydropyrimidine dehyrogenase gene mutation were calculated as 1.5% (3/200) and 0.000055% (1/18,043) in the analyzed samples. CONCLUSION: In this report, for the first time we documented the frequency of dehydropyrimidine dehydrogenase gene mutation in Turkish cancer patients. The determination of enzyme activity in suspected individuals and analysis of other mutations on a population basis would be the next steps for our country.

Hereditary intraosseous vascular malformation of the craniofacial region: an apparently novel disorder.

Primary intraosseous vascular anomaly, previously called intraosseous hemangioma, is a very rare malformation that is usually seen in the vertebral column and in the skull. It is exclusively described in sporadic cases and no hereditary component has yet been reported. The most commonly affected bones in the skull are the mandible and the maxilla, and life-threatening bleeding after a simple tooth extraction is frequently observed. Here, we report two consanguineous families containing a total of four affected patients manifesting primary intraosseous vascular malformation (VMOS (vascular malformation osseous)) of the craniofacial region. The phenotypic expression is remarkably similar in both families. The characteristic findings include severe blood vessel expansions within the craniofacial bones and midline abnormalities such as diastasis recti, supraumbilical raphe, and hiatus hernia. Malformation is restricted to the mandibular and maxillary area in the prepubertal age, and rapid expansion starts after age 12 or 13. A 15-year follow-up of one of the patients demonstrated that the vascular malformation did not extend beyond the craniofacial region despite severe involvement of almost all bones in the skull. Detailed clinical and radiological evaluation provided neither evidence of soft-tissue involvement nor any sign of gross arterial, venous, or combined malformations, indicating that bone changes are a primary rather than a secondary effect due to any other vascular anomaly in the craniofacial region. An antibody against a universal proliferation marker, Ki-67, detected nonproliferative, single-layered endothelial cells, suggesting that this abnormality is a vascular malformation rather than a hemangioma. alpha-actin staining (antibody against perivascular tissue such as smooth muscle cells (SMCs) and/or pericytes) demonstrated that pathologic vessels lost their surrounding supportive tissues, as was previously seen in other types of vascular anomaly. Homozygosity mapping excluded the following loci and/or genes: multiple cutaneous venous malformation (VMCM1; gene, TIE2) on chromosome 9p21; venous malformation with glomus cells (VMGLOM) on chromosome 1p22-p21; hereditary hemorrhagic telangiectasia type 1 (HHT1; gene, endoglin) and type 2 (HHT2; gene, activin) on chromosomes 9q34.1 and 12q11-q14, respectively; and cerebral cavernous malformation type 1 (CCM1; gene, KRIT1), type 2 (CCM2), and type 3 (CCM3) on chromosomes 7q11.2-q21, 7p15-p13, and 3q35.2-q27, respectively. To the best of our knowledge, this is a new disorder, which we call hereditary intraosseous vascular malformation of the craniofacial region.