Tailorable optical scattering properties of V-shaped plasmonic nanoantennas: a computationally efficient and fast analysis.

In this work, we introduce an efficient computational scheme, based on the macro basis function method, to analyze the scattering of a plane wave by V-shaped plasmonic optical nanoantennas. The polarization currents and scattered fields for the both symmetric and antisymmetric excitations are investigated. We investigate how the resonant frequency of the plasmonic V-shaped nanoantenna is tailored by engineering the geometrical parameters and by changing the polarization state of the incident plane wave. The computational model presented herein is faster by many orders of magnitude than commercially available finite methods, and is capable of characterizing all nanoantennas comprised of junctions and bends of nanorods.

Clinical characteristics and course of CD8+ cytotoxic variant of mycosis fungoides: a case series of seven patients.

BACKGROUND: Fewer than 5% of cases of mycosis fungoides (MF) present with a cytotoxic/suppressor CD8+ phenotype which, despite immunophenotypic similarities with CD8+ aggressive lymphomas, is regarded as a phenotypic variant of MF. Poikilodermatous MF showing a CD8+ phenotype has been reported to have a nonaggressive clinical behaviour and a good response to psoralen plus ultraviolet A treatment. OBJECTIVES: To perform a retrospective study of CD8+ MF cases diagnosed in the skin lymphoma clinic of Andreas Sygros Hospital. METHODS: We analysed the clinical characteristics, the immunophenotypic and molecular indices, as well as the clinical course of these patients. RESULTS: Seven cases of CD8+ MF (6.5% of all cases of cutaneous T-cell lymphoma) were diagnosed during 2002-2007. One of seven patients had stage IA, five stage IB and one stage IIB disease. Clinical characteristics were variable: four of seven patients presented with poikilodermatous plaques (in one of them lesions of lymphomatoid papulosis with CD8+ phenotype coexisted), one patient with classic MF, one with plantar MF and one with follicular MF. The time period between disease onset and diagnosis was long for most patients (up to 33 years). All patients received the recommended treatment according to TNM staging. Five of seven patients had complete remission, one partial response and one stable disease. CONCLUSIONS: Special clinical characteristics, such as hyperpigmentation and poikiloderma, are often noted in CD8+ MF cases. In our series CD8+ MF presented with a long-standing disease and indolent course suggesting that CD8+ cytotoxic immunophenotype may represent a marker of mild biological behaviour.

Bone marrow histological findings in systemic lupus erythematosus with hematologic abnormalities: a clinicopathological study.

BACKGROUND: The histopathologic features characterizing the involvement of the bone marrow (BM) in systemic lupus erythematosus (SLE) have not been systematically analyzed to date. OBJECTIVES: The aim of this study was to assess morphologic and immunohistochemical characteristics of BM involvement in SLE. PATIENTS AND METHODS: Clinical and serological data of 40 SLE patients with unexplained cytopenias were studied. Ten patients with myelodysplasia of refractory anemia (RA) were used as controls. BM aspiration, BM biopsy (BMB), and immunohistochemistry were carried out in patients and controls. BM fibrosis, BM necrosis, stromal edema, and abnormal localization of immature precursors (ALIP) were assessed according to standard criteria. RESULTS: Dyserythropoiesis and megakaryocytic atypias were uniform findings in SLE patients. The disruption of the normal BM architecture was a predominant SLE BM feature affecting cells of all three hemopoietic lineages, with both erythroid and megakaryocytic precursors tending to assume paratrabecular locations and ALIP aggregates being present in 27 cases. In addition, BM was hypocellular in 23 cases. BM necrotic alterations were evident in 90% of the cases. The density of reticulin content was generally increased. Vascular changes including dilatation of sinuses were manifest and were associated with the presence of necrotic alterations (P = 0.008). Hemoglobin levels correlated inversely with the presence of ALIP (P = 0.016). Upon comparing BMB features between SLE and RA controls there were striking similarities. CONCLUSIONS: BMB in patients with SLE and unexplained cytopenias presents a variety of histopathologic findings including BM necrosis, stromal alterations, hypocellularity, dyspoiesis, and distortion of normal BM architecture, characterized primarily by the presence of ALIP aggregates.

Clinical and morphological features of paediatric myelodysplastic syndromes: a review of 34 cases.

BACKGROUND: The clinical and morphological spectrum of myelodysplastic syndromes (MDS) during childhood has not yet been completely documented. We herein present the clinical features and morphological data from peripheral blood (PB), bone marrow aspirates (BMA) and bone marrow biopsies (BMB) of a series of paediatric MDS patients, with particular emphasis on their specific morphological characteristics and their diverse underlying genetic background. PATIENTS AND METHODS: Thirty-four patients with MDS (median age 8.45 y) were consecutively diagnosed and treated during a period of 15 y (1988-2002). Diagnosis was based on clinical manifestations, morphology of PB, BMA and BMB, and cytogenetic analysis of BM cells. Clonogenic methylcellulose cell cultures were performed in 23/34 patients. Patients were categorized into group A [26 primary/de novo MDS, i.e. refractory anaemia (RA) 18, RA with excess of blasts (RAEB) 2, RAEB in transformation (RAEB-t) 6] and group B (8 secondary MDS, i.e. RA 4, RAEB 1, RAEB-t 3). Treatment options varied according to protocols active during the period of the study and the availability of a suitable BM donor. Survival probabilities were estimated using the Kaplan-Meier method. RESULTS: Dysplastic features of the erythroid, myeloid and megakaryocytic lineage were detected at BMA in 85%, 50% and 90% of the patients, respectively, while decreased cellularity was found at BMB in 21/34 patients (60%). RA patients of group A presented at BMB significant hypocellularity (14/18) as a prominent finding due to decrease of the myeloid (13/18 patients) and/or the megakaryocytic (14/18 patients) lineage. Hypocellularity in RA was accompanied by dysplasia of the erythroid (17/18 patients) and megakaryocytic (16/18 patients) lineage, the presence of abnormal localization of immature precursors (ALIP, 8/18 patients), fibrosis (5/18) and stromal changes (11/18). Chromosomal aberrations were revealed in 17/34 patients, of which monosomy 7 was present in seven. Cell cultures demonstrated abnormal myeloid and/or erythroid in vitro clonal growth pattern in all the examined patients. An associated disorder or inherited disease, was identified in 14/26 patients (54%) with primary MDS. Cumulative survival of group A patients was 44.2% (RA 66.6%, RAEB/RAEBt 14.6%; p = 0.001), and of the whole group 42.4%, at 14 y. CONCLUSIONS: Hypocellularity of significant degree is a constant and prominent feature among paediatric MDS, especially those with RA. A large variety of associated disorders underlies the clinical appearance of paediatric MDS, reflecting their marked heterogeneity. RA represents the prominent subtype during childhood (69% in this study), and it appears to have the best prognosis, while prognosis of RAEB/RAEBt remains extremely poor.

Primary breast lymphoma in a male patient.

Primary lymphoma of the male breast is extremely rare. We report a case of a diffuse large B-cell lymphoma in a male patient. A 67-year-old man presented with a palpable mass in the right breast and ipsilateral axillary lymphadenopathy. At operation a 6 x 5 x 4-cm mass was excised, and a frozen section demonstrated malignancy. A modified radical mastectomy was then performed, together with axillary lymph node clearance. Histological examination established the diagnosis of a primary non-Hodgkin's lymphoma of the breast. The patient was referred for chemotherapy and died a year later from systemic disease involving the adrenals. The importance of early diagnosis is emphasized; this should be based on an excisional biopsy or aspiration cytology. As patients with primary breast lymphoma (PBL) have a better prognosis than those with carcinoma of the breast or patients with extranodal lymphomas, a multidisciplinary approach including surgery, radiotherapy, and chemotherapy when needed would result in a more favorable outcome.

Combined therapy with rituximab plus cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) for Sjögren's syndrome-associated B-cell aggressive non-Hodgkin's lymphomas.

OBJECTIVE: To determine the safety and therapeutic response of a regimen consisting of cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) plus rituximab in patients with Sjögren's syndrome (SS) and aggressive non-Hodgkin's lymphoma (NHL). METHODS: Four SS patients with aggressive marginal zone NHL were enrolled in this trial. All patients were classified according to the newly proposed revised European-American classification of lymphoid neoplasms. Three out of four patients also had mixed cryoglobulinaemia (MC) of type II. They were treated every 3 weeks for eight cycles of CHOP. Patients also received rituximab, at a dose of 375 mg per square metre, on day 1 of each of the eight cycles of CHOP. Four weeks after completion of the eighth course of CHOP plus rituximab and every 6 months thereafter, patients were re-evaluated for response. RESULTS: Complete remission of lymphoma was achieved in all four patients. The lymphoma patients remained in remission for a period of 23, 15, 12 and 10 months respectively, while certain signs and symptoms of MC type II (purpura, peripheral neuropathy and arthralgias) significantly improved with treatment. In addition, the titres of circulating cryoglobulins and RF decreased, while C4 levels returned to normal. CONCLUSION: CHOP plus rituximab was well tolerated and proved effective in SS patients with aggressive NHL. Our observations may warrant a larger controlled trial to assess the effectiveness of this regimen in such patients.

An extensive traumatic degloving lesion of the penis. A case report and review of the literature.

Traumatic lesions of the penis and scrotum are often encountered in urological emergency departments. We describe a case of complete unraveling of the penile skin and partial avulsion of the scrotal skin, which was treated without the need for a skin graft, which is usually the selected mode of treatment. Instead, we believe that a less aggressive surgical approach is more beneficial for the patient since it allows faster healing and prevents the development of complications.

Concomitant angioimmunoblastic T-cell lymphoma and low grade B-cell lymphoproliferative disorder.

The presence of a rearranged immunoglobulin gene, in addition to the expected T-cell receptor gene rearrangement, is a frequent, albeit poorly understood, finding in the setting of angioimmunoblastic lymphadenopathy. A case of an angioimmunoblastic T-cell lymphoma is presented, where this apparently paradoxical dual gene rearrangement could be ascribed to the coexistence of an occult B-cell lymphoproliferative disorder.

Molecular analysis of bcl-1/IgH junctional sequences in mantle cell lymphoma: potential mechanism of the t(11;14) chromosomal translocation.

Mantle cell lymphoma (MCL) is characterized by the t(11;14) translocation that juxtaposes the bcl-1 locus to immunoglobulin (Ig) gene sequences and leads to deregulation of cyclin D1 gene. t(11;14) is thought to result from an error of the recombinase during D-JH Ig gene assembly; however, data on the underlying mechanism and candidate recombination-targeting motifs in the major translocation cluster (MTC) of the bcl-1 gene are lacking. bcl-1/IgH junctional sequences from seven MCL patients were amplified by PCR using primers targeting MTC and JH sequences on chromosomes 11q13 and 14q32, respectively. PCR products were directly sequenced and junctional sequences were searched for homology to known germline D genes. bcl-t MTC breakpoints were searched for the presence of possible recombination target motifs; heptamers, nonamers, binding sequence of the bp45 nuclease, x-like sequences and D gene segments. bcl-1/JH junctions were found to bear homology to D gene segments (DLR3, DM and DIR5) in 3/7 MCL samples. A computer-based search in previously published and/or submitted to GenBank bcl-1/JH junctional sequences identified homology to D genes in 1/4 MCL tumour samples and 1/4 MCl cell lines; DXP4 or D23/7 and DHQ52 or D22/21 or DXP5, respectively. The MTC locus contained motifs with homology to bp45 nuclease binding sequence, x-like sequences, heptamers/nonamers, D-like DIR genes and non-homologous recombination short (6 bp) DNA sequences. The above data indicate that the t(11;14) translocation in MCL may also occur at a more mature stage of B-cell ontogeny than previously thought, i.e. during VH-to-DJH rearrangement. Various known recombination motifs within MTC may contribute to an illegitimate recombination event between bcl-1 and DJH.

Extensive apoptosis of bone marrow cells as evaluated by the in situ end-labelling (ISEL) technique may be the basis for ineffective haematopoiesis in patients with myelodysplastic syndromes.

Apoptosis is a gene-directed cellular self-destruction which begins with internucleosomal cleavage of DNA and ends eventually with fragmentation of the nucleus. We have shown that the technique of ISEL of fragmented DNA appears to be an accurate and reliable measurement of the early stages of apoptosis. The present study was undertaken in order to define the incidence of programmed cell death in bone marrow (BM) haematopoietic and stromal cells of myelodysplastic syndromes (MDS). The ISEL technique was employed in 21 BM biopsies of MDS patients. The analysis showed that in 11/21 patients, >70% cells (high score) were undergoing programmed cell death while 5 patients showed up to 1/3 of the biopsy containing apoptotic cells and 2 patients had only few occasional ISEL positive cells. Stromal cells including fat cells, endothelial cells and fibroblasts were frequently in apoptosis in large clusters. Our results indicate that extensive apoptosis of haematopoietic cells documented in BM biopsies of MDS patients may be the explanation for the ineffective haematopoiesis which is the hallmark of these disorders.

Somatic hypermutation of immunoglobulin variable region genes: focus on follicular lymphoma and multiple myeloma.

Analysis of the rearranged immunoglobulin variable region gene hypermutation has provided important information concerning the clonal history and ontogenetic origin of various B-cell lymphoproliferative disorders. Under the selective pressure of antigen, mutational events in immunoglobulin genes will fine tune survival of B-cell clones bearing immunoglobulin with high affinity for antigen. Our studies aimed at analyzing neoplastic disorders originating from germinal and post-germinal center B-cells: follicular lymphoma and multiple myeloma, respectively. Despite the already acknowledged evidence for a selectable distribution of mutations within the clonal immunoglobulin variable heavy chain genes, very little is known about the contribution of light chains in the process of antigen selection. In follicular lymphoma, a more limited pattern of somatic mutation with less evidence of antigen selection was observed in variable kappa light chain genes (40%) than in their partner heavy chain genes (80%). In myeloma, hypermutation of variable light chain genes, with a distribution suggestive of antigen selection, was frequently observed. Based on these data and recent reports it appears that the light chain expressed by the clonogenic myeloma B-cells plays a pivotal role in the antigen selection process. Additionally, abortive kappa light chain variable region genes in lambda-expressing myelomas carried a significant number of somatic mutations indicating that the cell of origin is open to the hypermutation machinery at that particular developmental stage irrespective of antigen selection.

Follicular lymphoma immunoglobulin kappa light chains are affected by the antigen selection process, but to a lesser degree than their partner heavy chains.

Follicular lymphoma cells carry surface immunoglobulin whose heavy chain variable (VH) regions exhibit considerable divergence from the aminoacid sequence predicted by the germline nucleotide sequence as a result of the somatic hypermutation process. The present study examined the extent of somatic hypermutation in follicular lymphoma kappa light chain variable region (V kappa) genes about which the available data is limited. DNA extracted from fresh frozen lymph node tissue of 14 patients with follicular lymphoma at diagnosis was subjected to polymerase chain reaction (PCR) amplification aimed at detecting clonal VH and VL (L: light chain) gene rearrangements. Clonal V kappa gene rearrangements were detected in 10/14 cases. Amplified VH and V kappa genes of these 10 cases were directly sequenced by the dideoxy-chain termination method. In all cases, rearranged VH genes demonstrated numerous mutations clustering in the complementarity determining regions (CDRs), in keeping with previous reports. The degree of divergence of the rearranged V kappa genes from the closest homologous germline V kappa genes varied significantly. Furthermore, two patterns of mutations were observed: (i) in six cases (60%), mutations were most often of the replacement (R) type (changing the aminoacid sequence of the encoded polypeptide) in the CDRs and of the silent (S) type (leaving the aminoacid sequence of the encoded polypeptide unchanged) in the framework regions (FWRs) resulting in R:S ratios significantly greater than would have occurred by chance: (ii) in four cases (40%), very few or no mutations were observed and the distribution of mutations as well as the R:S mutation ratios did not differ significantly from what would have occurred by chance alone. These findings imply that, compared to their partner heavy chains, the kappa light chains of follicular lymphoma neoplastic B-cells' surface immunoglobulin (sIg): (i) are less affected by somatic hypermutation: (ii) play a less significant role in the antigen selection process.

t(14;18) chromosomal translocation in follicular lymphoma: an event occurring with almost equal frequency both at the D to J(H) and at later stages in the rearrangement process of the immunoglobulin heavy chain gene locus.

bcl-2/IgH fusion is considered a genetic error which occurs at the diversity (D) to joining (J(H)) stage of the gene rearrangement process in the immunoglobulin heavy chain (IgH) gene locus. Translocations of the bcl-2 protooncogene to the IgH locus at ontogenetically later IgH gene rearrangements are thought to represent exceptions. In the present study we analysed the junctional nucleotide sequence of 18 bcl-2/IgH fusion genes identifiable by polymerase chain reaction performed on DNA extracted from diagnostic lymph node tissue of 14 follicular lymphoma patients. In all clones studied, segments of variable length were found interposed between bcl-2 and J(H) gene sequences. Nucleotide sequence data analysis and comparisons performed with the corresponding germline sequences using the GenBank/EMBL database revealed the presence of D segments in most of the bcl-2/IgH fusion genes under study (13/18). By the same kind of computer-aided analysis, previously unrecognized D segments were identified in many published junctional sequences. These results suggest that bcl-2/IgH fusion events are very prevalent in rather more differentiated stages in B-cell ontogeny than previously recognized.

Analysis of the kappa light chain variable region in multiple myeloma.

The study of immunoglobulin heavy chain gene rearrangements in multiple myeloma has revealed extensive divergence from the germline sequences, but no intraclonal diversity with disease evolution. Our study investigated the state of the rearranged kappa light chain variable region (V kappa) gene segments as well as abortive V kappa family gene usage in cases of multiple myeloma expressing lambda light chain. We studied 11 cases of kappa and five cases of lambda light chain-expressing multiple myeloma. Total cellular RNA was extracted from the bone marrow of patients with overt disease and subjected to reverse transcription-polymerase chain reaction (RT-PCR) analysis to amplify clonally rearranged variable region sequences. Direct nucleotide sequencing by the dideoxy-chain termination method was performed on the RT-PCR products. We did not observe preferential usage of certain V kappa gene families. Mutation frequencies of the V kappa segments varied in number. In the majority of cases, extensive somatic mutations occurred within the complementarity determining regions (CDRs) of V kappa, whereas only a limited degree of divergence from the germline was observed in others. In all cases studied. replacement mutations tended to cluster in the CDRs, a finding compatible with an antigen-driven somatic hypermutation process. In 3/5 cases of lambda light-chain expressing multiple myeloma, abortively rearranged V kappa gene segments were amplified from genomic DNA; in two cases a non-templated nucleotide insertion rendering the V kappa sequences out-of-frame was observed, and in the third a stop codon was identified in the open reading frame of the V kappa sequence. Somatic mutations were observed in all cases of abortive V kappa genes studied; however, their distribution does not suggest selection by antigen. We conclude that somatic mutations observed in the V kappa regions of myeloma cells are of variable extent and suggest operation of the antigen selection process. Lack of or minimal somatic hypermutation in a few cases may be in some way implicated in the biological heterogeneity of the disease.

Secondary malignancies in a child with Hodgkin's disease: T-cell lymphoma and myelodysplastic syndrome evolving into acute nonlymphoblastic leukaemia.

Hodgkin's disease (HD) has been linked to an increase risk of second malignant neoplasms (SMN), especially non-Hodgkin's lymphoma (NHL) and acute nonlymphoblastic leukaemia (ANLL). The mutagenic property of cytotoxic therapy as well as defective immunity have been implicated as playing a major role in the development of SMN in patients previously treated for HD. We report a case of a 14-year-old girl with HD who developed two different second malignancies within a latent period of 28 months following HD diagnosis. The patient presented initially with bilateral cervical and supraclavicular as well as mediastinal and paraaortic lymphadenopathy. She was staged as IIIA, nodular sclerosing type HD, and was given eight alternative cycles of MOPP-ABVD followed by "mantle" field radiotherapy to a total dose of 3.3 Gy plus 0.4 Gy to the upper mediastinum. Within 8 months following the completion of therapy, a period of myelodysplasia and progressive severe immune deficiency, considered as a result of initial treatment, occurred. Eighteen months after HD diagnosis while the patient was continuously neutropenic and heavily immunocompromised, a peripheral T-cell lymphoma of the angiocentric immunoproliferative lesion type (AIL) Grade III, appeared in both lungs within and beyond the radiation field, with no evidence of HD in biopsy specimens. After institution of a new chemotherapy regimen (L17M), a satisfactory response regarding NHL lesions was noted. However, 10 months later the myelodysplastic syndrome (MDS) accompanied by complex chromosomal abnormalities evoluted to frank ANLL with a rapid fatal course. This case supports the hypothesis that combined modality treatment accompanied by severe immunodeficiency may result in the development of multiple second malignancies even within a very short latent period, especially in a subgroup of HD patients who may be particularly increased risk of second cancers.

Primary granulocytic sarcoma of the testis.

An unusual case of a 44-year-old patient with primary left testicular granulocytic sarcoma is presented. Iliac and paraaortic lymph node involvement was also demonstrated at staging laparotomy. The patient was treated with left orchiectomy and early intensive chemotherapy, but relapsed with a right testicular mass 14 months later. No evidence of leukemic progression was found at that time, and he was treated with right orchiectomy, combined with irradiation to the scrotum, inguinal, iliac and paraaortic lymph nodes. Unfortunately, he developed myelogenous leukemia 7 months later. A complete remission of 6 months duration was achieved with combination chemotherapy. The patient then relapsed, and an effort to induce a second remission was unsuccessful. He eventually died almost 3 years after initial diagnosis. We conclude that primary granulocytic sarcoma represents a systemic disease. Despite early intensive treatment its prognosis remains poor.