Fast-suppressor screening for new components in protein trafficking, organelle biogenesis and silencing pathway in Arabidopsis thaliana using DEX-inducible FREE1-RNAi plants.

Membrane trafficking is essential for plant growth and responses to external signals. The plant unique FYVE domain-containing protein FREE1 is a component of the ESCRT complex (endosomal sorting complex required for transport). FREE1 plays multiple roles in regulating protein trafficking and organelle biogenesis including the formation of intraluminal vesicles of multivesicular body (MVB), vacuolar protein transport and vacuole biogenesis, and autophagic degradation. FREE1 knockout plants show defective MVB formation, abnormal vacuolar transport, fragmented vacuoles, accumulated autophagosomes, and seedling lethality. To further uncover the underlying mechanisms of FREE1 function in plants, we performed a forward genetic screen for mutants that suppressed the seedling lethal phenotype of FREE1-RNAi transgenic plants. The obtained mutants are termed as suppressors of free1 (sof). To date, 229 putative sof mutants have been identified. Barely detecting of FREE1 protein with M3 plants further identified 84 FREE1-related suppressors. Also 145 mutants showing no reduction of FREE1 protein were termed as RNAi-related mutants. Through next-generation sequencing (NGS) of bulked DNA from F2 mapping population of two RNAi-related sof mutants, FREE1-RNAi T-DNA inserted on chromosome 1 was identified and the causal mutation of putative sof mutant is being identified similarly. These FREE1- and RNAi-related sof mutants will be useful tools and resources for illustrating the underlying mechanisms of FREE1 function in intracellular trafficking and organelle biogenesis, as well as for uncovering the new components involved in the regulation of silencing pathways in plants.

Coexpression of CD43 by benign B cells in the terminal ileum.

Expression of CD43 by B cells is often used as a diagnostic criterion in favor of a B-cell lymphoproliferative disorder, including small lymphocytic lymphoma/chronic lymphocytic leukemia, mantle cell lymphoma, Burkitt lymphoma, precursor B-lymphoblastic lymphoma, and a subset of marginal zone B-cell lymphomas. Benign B cells generally do not coexpress CD43. The authors analyzed 20 biopsies of the terminal ileum for nonneoplastic disease for expression of CD43 and compared them with other sites and with CD20, CD138, and CD3 reactivity. The majority of cases (85%) showed strong coexpression of CD43 by benign perifollicular B cells. The presence of CD43 coexpression in B-cell populations of the terminal ileum, including those of Peyer's patches, should not be used as a diagnostic parameter to differentiate extranodal marginal zone B-cell lymphoma of MALT type from reactive processes.

Immunophenotyping of angioimmunoblastic T-cell lymphomas by multiparameter flow cytometry.

Angioimmunoblastic T-cell lymphoma (AITL) is a distinct form of peripheral T-cell lymphoma (PTCL) frequently involving lymph nodes, spleen and bone marrow, and is associated with systemic symptoms. Its histologic features may be subtle at an early phase and difficult to diagnose. Despite the success of flow cytometry (FCM) in diagnosing B-cell neoplasm, FCM has not been widely accepted as a useful method for establishing the diagnosis of PTCL. Recently, the neoplastic T-cells in AITL have been shown to express CD10. We prospectively applied multiparameter FCM immunophenotyping to three cases of histologically confirmed AITL and identified a small (5-7%) population of CD4+/CD10+ T-cells in two cases. In one case, the CD4+/CD10+ population lacked surface signals of CD3 and CD7, but strongly expressed CD2, whereas CD45 expression was very weak; partial loss of surface CD3 was observed in the other. None of the lymph nodes with reactive hyperplasia, B-cell lymphomas, or Hodgkin's lymphoma studied during the same time period contained the CD4+/CD10+ population. These findings suggest that addition of CD4/CD10 and CD3/CD10 to FCM immunophenotyping panels is useful in the diagnosis of AITL. To the best of our knowledge, this is the first report to demonstrate CD10-expressing T-cells in AITL by FCM.

Creation of ureteropelvic junction obstruction and its correction by chemical glue-assisted laparoscopic dismembered pyeloplasty.

PURPOSE: We established a porcine model of ureteropelvic junction (UPJ) obstruction using a laparoscopic technique and assessed the outcome of standard suture-assisted and chemical glue-assisted laparoscopic pyeloplasty. MATERIALS AND METHODS: Female domestic pigs (N = 20) underwent laparoscopic suture-ligature to create UPJ obstruction. One month later, laparoscopic end-to-end anastomosis was performed to correct the obstruction: with standard suturing techniques in 10 animals and with chemical (cyanoacrylate) glue in the other 10. Postoperative ureteral stents were not used. Four weeks postoperatively, intravenous urography was performed to evaluate the patency of the anastomoses. The UPJ was procured by laparotomy to assess the anastomoses and periureteral fibrosis histologically. RESULTS: The UPJ obstruction was created in an average of 15 +/- 6 minutes. There was no early postoperative mortality. Eighteen pigs survived for at least 1 month, and UPJ obstruction developed in 17 (95%). Microscopically, the lumen of the UPJ was partially occluded, measuring an average of 40% +/- 5% of normal. After laparoscopic correction, a patent UPJ was found in seven of nine animals treated with traditional sutures. Among the eight animals with chemically glued anastomoses, none had a patent UPJ, and severe periureteral adhesions and intraluminal fibrosis were noted at the pyeloplasty site. Marked ureteral tortuosity was present in six of the eight pigs receiving glue-assisted pyeloplasty but in none of the animals having suture-assisted pyeloplasty. CONCLUSIONS: Ureteropelvic junction obstruction was established by laparoscopic suture-ligature in a porcine model with a 95% success rate. Chemical glue-assisted anastomosis was inferior to standard laparoscopic sutures for pyeloplasty to correct the obstruction.

Acute leukemia with myeloid, B-, and natural killer cell differentiation.

Biphenotypic acute leukemias account for 4% to 8% of all acute leukemias. Most of these leukemias are of myeloid-B-cell or myeloid-T-cell lineage. Acute myeloid-natural killer cell leukemia has been recognized recently. We report the first case, to our knowledge, of CD56(+) acute leukemia showing unequivocal myeloid and B-cell differentiation in a 20-year-old woman, whose blast cells were positive for myeloperoxidase, CD13, CD33, CD117, terminal deoxynucleotidyl transferase, CD19, CD20, CD22, CD34, HLA-DR, and CD56 but negative for CD3, CD5, CD7, and CD10. Rare Auer rods were identified in the blast cells. Polymerase chain reaction assays showed rearrangement of immunoglobulin heavy-chain gene and absence of Epstein-Barr virus DNA. We propose that this novel form of multilineage leukemia may represent the neoplastic counterpart of a progenitor that can give rise to myeloid, B, and natural killer cells.

High frequency of t(11;18) in gastric mucosa-associated lymphoid tissue lymphomas in Taiwan, including one patient with high-grade transformation.

t(11;18)(q21;q21), the most frequent chromosomal aberration of mucosa-associated lymphoid tissue (MALT) lymphoma, occurs in 30% of gastric patients. Although the translocation is often associated with an 'aggressive' course, it has not been described in transformed MALT lymphomas. We screened 15 gastric MALT lymphomas [three with concurrent or subsequent high-grade transformation and 11 diffuse large B-cell lymphomas (DLBCLs)] in Chinese patients for t(11;18). t(11;18) was found in 9/15 (60%) MALT lymphomas, but not in any DLBCLs. One patient, with subsequent high-grade transformation, showed the translocation in low- and high-grade lesions. t(11;18) was frequent in Chinese gastric MALT lymphomas and unusually one transformed lymphoma carried the translocation.

Primary brain lymphoma: a report of eight cases from a medical center in southern Taiwan.

BACKGROUND: Primary brain lymphoma (PBL) in Taiwan has been reported only in three series with very limited immunophenotypic characterization. METHODS: We retrospectively studied PBL cases with history review, immunohistochemistry, and in situ hybridization (ISH) for Epstein-Barr virus-encoded mRNA (EBER) from a single institution in southern Taiwan during 1989-2000. RESULTS: We found eight cases of PBL including four males and four females with mean age of 64.1 years and median of 63.0. The major presenting symptoms were headache, poor memory, slurred speech, and hemiplegia in three patients each. All patients had stage I solitary tumor. Half of the patients received tumor excision, the other half, stereotactic biopsy. Seven cases were of diffuse large B-cell type (DLBL), with expression of bcl-2 in six cases. They were all negative for CD5, CD10, bcl-6, and EBER. The eighth patient had anaplastic large cell lymphoma (ALCL) of T-cell phenotype with expression of cytotoxic markers and was positive for EBER. Two were lost to follow up. The median follow-up time for the remaining six was 11.2 months (range, 5.5 - 25.0). They all received radiotherapy with initial complete remission. Two died of the disease, another of cardiopulmonary failure, and the other of stroke or recurrence. The remaining two were free of disease for 9.6 and 25.0 months after radiotherapy alone. The 1-year survival rate was 60%. CONCLUSIONS: We have fully characterized eight cases of PBL, including seven DLBLs and one ALCL, in southern Taiwan that occurred in an older age group. Old age, immunophenotype (bcl-2-positivity and bcl-6-negativity), and lack of systemic chemotherapy were probably responsible for the shorter survival as compared to other studies. Radiotherapy seems to be effective for inducing complete remission and even long-term survival in some patients, however, systemic chemotherapy should be administered to prevent recurrence and to achieve long-term survival.

High dose chemotherapy and allogenic peripheral blood stem cell transplantation for multiple myeloma evolving from intra-abdominal plasmacytoma.

Solitary plasmacytomas include extramedullary plasmacytomas and those found in the bone. Seventy percent of patients are male and the median age is 50-55 years, younger than that for plasma cell myeloma. Most solitary plasmacytomas of bone eventually evolve to plasma cell myeloma within 2-10 years, while the extramedullary ones do so infrequently. We present an unusual case of intra-abdominal plasmacytoma in a young woman which was misdiagnosed and treated as T cell lymphoma initially. Typical manifestations of plasma cell myeloma appeared one year later. High dose chemotherapy followed by allogeneic peripheral stem cell blood transplantation (allo-PBSCT) was given. Relapse in skin occurred one year after allo-PBSCT, and was treated with wide excision and local irradiation. The patient was well and alive without evidence of disease 4 years after wide excision of the recurrence of chest wall solitary plasmacytoma and local radiotherapy.

Aggressive natural killer cell lymphoma/leukemia.

We report a case of aggressive natural killer (NK) cell lymphoma/leukemia in a 70-year-old woman presenting with fever, hepatosplenomegaly, retroperitoneal lymphadenopathy, and elevated serum CA19-9. The patient died 4 days after diagnosis. Neoplastic NK cells were identified in the blood and retroperitoneal lymph node biopsy. Their phenotypes were confirmed by extensive flow cytometric and immunohistochemical studies. In situ hybridization for Epstein-Barr virus (EBV)-associated RNA (EBER) was positive. Various forms of NK cell neoplasm were reviewed and discussed.