Femtosecond laser fluorescence and propagation in very dense potassium vapor

Femtosecond (fs) laser propagation and fluorescence of dense potassium vapor was studied, and the spectral region around the first and the second doublets of the principal series lines of potassium atoms was investigated. In our search we did not observe the conical emission in the far field, although it was previously observed in the case of rubidium. We discuss the possible reason of this unexpected result. The fluorescence spectrum revealed Rb impurity resonance lines in emission due to the collisional redistribution from the K(4p) levels into the Rb(5p) levels. In the forward propagation of 400 nm femtosecond light we observed the molecular band red shifted from potassium second doublet. However, no molecular spectrum was observed when the mode-locked fs laser light was discretely tuned within the wings of the first resonance lines, at 770 nm.

mSYD1A, a mammalian synapse-defective-1 protein, regulates synaptogenic signaling and vesicle docking

Structure and function of presynaptic terminals are critical for the transmission and processing of neuronal signals. Trans-synaptic signaling systems instruct the differentiation and function of presynaptic release sites, but their downstream mediators are only beginning to be understood. Here, we identify the intracellular mSYD1A (mouse Synapse-Defective-1A) as a regulator of presynaptic function in mice. mSYD1A forms a complex with presynaptic receptor tyrosine phosphatases and controls tethering of synaptic vesicles at synapses. mSYD1A function relies on an intrinsically disordered domain that interacts with multiple structurally unrelated binding partners, including the active zone protein liprin-α2 and nsec1/munc18-1. In mSYD1A knockout mice, synapses assemble in normal numbers but there is a significant reduction in synaptic vesicle docking at the active zone and an impairment of synaptic transmission. Thus, mSYD1A is a regulator of presynaptic release sites at central synapses.

Neurobeachin regulates neurotransmitter receptor trafficking to synapses

The surface density of neurotransmitter receptors at synapses is a key determinant of synaptic efficacy. Synaptic receptor accumulation is regulated by the transport, postsynaptic anchoring, and turnover of receptors, involving multiple trafficking, sorting, motor, and scaffold proteins. We found that neurons lacking the BEACH (beige-Chediak/Higashi) domain protein Neurobeachin (Nbea) had strongly reduced synaptic responses caused by a reduction in surface levels of glutamate and GABA(A) receptors. In the absence of Nbea, immature AMPA receptors accumulated early in the biosynthetic pathway, and mature N-methyl-d-aspartate, kainate, and GABA(A) receptors did not reach the synapse, whereas maturation and surface expression of other membrane proteins, synapse formation, and presynaptic function were unaffected. These data show that Nbea regulates synaptic transmission under basal conditions by targeting neurotransmitter receptors to synapses.

Treatment with luteinizing-hormone-releasing hormone antagonist sb-75 decreases levels of epidermal growth-factor receptor and its messenger-RNA in ov-1063 human epithelial ovarian-cancer xenografts in nude-mice

The aim of this study was to investigate the effect of administration of LH-RH antagonist SB-75 and agonist [D-Trp(6)]LH-RH on receptors for epidermal growth factor (EGF) in OV-1063 human epithelial ovarian cancer. Female athymic nude mice bearing xenografts of OV-1063 human epithelial ovarian cancer were treated for 3 weeks with the modern LH-releasing hormone (LH-RH) antagonist [Ac-DNal(2)(1), D-Phe(4Cl)(2), D-Pal(3)(3), D-Cit(6), D-Ala(10)] LH-RH (SB-75, Cetrorelix), the agonist [D-Trp(6)]LH-RH, or bombesin/gastrin-releasing peptide antagonist RC-3095. SB-75 and [D-Trp(6)] LH-RH were injected s.c. at doses of 100 mu g/day, and RC-3095 was injected at a dose of 40 mu g/day. Tumor growth, as measured by percentage change in tumor volume, was significantly inhibited by the treatment with SB-75, but not by [D-Trp(6)] LH-RH or RC-3095. Treatment with SB-75 greatly decreased the levels of mRNA for EGF receptor and reduced the number of EGF binding sites on tumor membranes. Effects of SB-75 on EGF receptors might be related to inhibition of tumor growth. Our findings support the view that LH-RH antagonists such as SB-75 could be considered for possible hormonal therapy of epithelial ovarian cancer.

A retrospective audit of clinicopathological attributes and treatment outcomes of adolescent and young adult non-Hodgkin lymphomas from a tertiary care center

Background:

The uniqueness of adolescent and young adult (AYA) non-Hodgkin lymphomas (NHL) with respect to biology and treatment have largely remained unanswered due to marked heterogeneity in treatment, paucity of prospective, or retrospective studies and poor representation of AYA in clinical trials. This audit attempts to put forward the clinicopathological attributes and treatment outcomes of AYA NHL treated with both pediatric and adult protocols from a single centre in a developing country.

Patients and Methods:

Hospital records of all consecutive NHL patients registered in lymphoma clinic from January 2007 to May 2010 were reviewed for information on demography, clinical features, histology subtype, staging, treatment regimen, response rates, toxicities, and follow up. Two-year progression-free (PFS) and overall survival (OS) were calculated with Kaplan-Meier method.

Results:

AYA NHL constituted 4% of all lymphomas. Diffuse large B-cell (DLBL) was the most frequent subtype. Following were the 2-year PFS and OS - DLBL 64%, 76.9%, Burkitt's lymphoma: 56%, 56%, lymphoblastic lymphoma: 33.2%, 44%. Our results did not show any improvement in outcome of DLBL with the use of Burkitt's lymphoma like regimen.

Conclusions:

This study highlights some of the key features of AYA NHL occurring in developing world.

Case report: Eculizumab rescue of severe accelerated antibody-mediated rejection after ABO-incompatible kidney transplant

ABO-incompatible (ABOI) living donor kidney transplantation has become a well-accepted practice with standard protocols using perioperative antibody-depleting therapies to lower blood group titers to an acceptable threshold for transplantation. However, a subset of patients will experience accelerated antibody-mediated rejection (AMR) after ABOI kidney transplantation and require aggressive intervention to prevent allograft loss. Here in we report the successful use of terminal complement inhibition with eculizumab to rescue an ABOI kidney allograft with accelerated AMR refractory to salvage splenectomy and daily plasmapheresis. This case emphasizes the fact that, despite close postoperative surveillance and aggressive intervention, graft loss from accelerated AMR after ABOI kidney transplantation remains a very real risk. Eculizumab may offer a graft-saving therapeutic option for isolated cases of severe AMR after ABOI kidney transplantation refractory to standard treatment.

Very early recurrence of anti-Phospholipase A2 receptor-positive membranous nephropathy after transplantation

Membranous nephropathy is a common cause of adult nephrotic syndrome, with recent evidence suggesting that 70% of idiopathic disease is associated with anti-Phospholipase A(2) receptor autoantibodies. We describe a 63-year-old man with membranous nephropathy who underwent a kidney transplant and developed recurrent membranous nephropathy with fine granular co-localization of Phospholipase A(2) receptor and IgG evident on transplant biopsy on day 6 and elevated circulating levels of serum anti-Phospholipase A(2) receptor autoantibody that declined over time in conjunction with improvement in the serum creatinine and urinary protein. This is a very early case of Phospholipase A(2) receptor-associated recurrent membranous nephropathy with circulating anti-Phospholipase A(2) receptor autoantibody, which supports the emerging evidence that idiopathic membranous nephropathy is an autoimmune disease.

Case report: successful treatment of recurrent focal segmental glomerulosclerosis with a novel rituximab regimen

Focal segmental glomerulosclerosis (FSGS) is the cause of renal failure in more than 10% of pediatric patients undergoing renal transplantation. Recurrent FSGS is a major cause of pediatric allograft failure, with the risk increasing for patients undergoing retransplantation. Standard therapy for recurrent posttransplantation FSGS includes the use of intensive plasmapheresis (PP) in conjunction with cyclophosphamide or high-dose cyclosporine. However, many patients exhibit refractory disease, with rapid progression to allograft loss despite these interventions. Prior studies have reported conflicting data on the efficacy of adding rituximab therapy to the standard treatment regimen for recurrent posttransplantation FSGS. Here we present a successful therapeutic protocol with rapid elimination of PP after initiation of rituximab therapy for an adolescent patient with recurrent FSGS in the immediate postoperative period. The patient has maintained excellent allograft function through 12 months posttransplantation.

Histopathological audit of splenectomies received at a cancer hospital

BACKGROUND

There are few studies in the literature studying the yield of the diagnostic splenectomy in a suspicious lymphoma case. Moreover, their relevance is limited owing to low number of cases, the use of selection criteria, and the lack of modern ancillary studies. We present a histopathological review of splenectomy specimens referred as a case of lymphoma to our center.

MATERIALS AND METHODS

The medical charts and laboratory data on all patients of all splenectomy specimens between the years 2003 and 2008 were reviewed. Morphological and immunohistochemical features were analyzed and the lymphomas were sub-typed in accordance to 2008 WHO Classification of Hematolymphoid Neoplasms. Flow cytometry immunophenotyping available in few cases was correlated.

RESULTS

A total of 46 cases studied included splenic marginal zone lymphoma (SMZL) (19 cases), splenic diffuse large B-cell lymphoma (DLBCL) (14 cases), splenic diffuse red pulp B-cell lymphoma (DRP) (five cases), follicular lymphoma (three cases), hairy cell leukemia (HCL) (two cases), HCL variant (HCLv) (1 case), 1 case of hepatosplenic gamma delta T-cell lymphoma (TCL), and 1 cases of TCL (not otherwise specified).

CONCLUSIONS

Predominantly splenic lymphoma is a biologically heterogeneous entity, ranging from low-grade SMZL to high-grade DLBCLs. TCLs constituted only 4% of all our cases. DRP, HCL, and HCLv have similar diffuse red pulp patterns of splenic involvement and are differentiated based on flow cytometric immunophenotyping. We had a large number of splenic DLBCL and none of these involved bone marrow (BM), while all other lymphoma subtypes had BM involvement (stage IV disease). Morphological and immunophenotypic (immunohistochemistry and flow cytometry) features of BM and splenectomy specimen need to be correlated to differentiate these rare though similar-looking entities with overlapping features.

Antimicrobial Activity of Terminalia catappa, Manilkara zapota and Piper betel Leaf Extract

Aqueous and methanol extract of the leaves of Terminalia catappa L., Manilkara zapota L. and Piper betel L. were evaluated for antibacterial activity against 10 Gram positive, 12 Gram negative bacteria and one fungal strain, Candida tropicalis. Piperacillin and gentamicin were used as standards for antibacterial assay, while fluconazole was used as standard for antifungal assay. The three plants showed different degree of activity against the microorganisms investigated. The methanolic extract was considerably more effective than aqueous extract in inhibiting the investigated microbial strains. The most active antimicrobial plant was Piper betel.

Role of RT-PCR and FISH in diagnosis and monitoring of acute promyelocytic leukemia

BACKGROUND

Patients with a presence of Promyelocytic Leukemia-Retinoic Acid Receptor Alpha (PML-RARA) genes rearrangement predict a favorable response to all-trans retinoic acid (ATRA), and a significant improvement in survival. Therefore, establishing the presence of PML-RARA rearrangement is important for optimal patient management.

AIM

The objective of this study is to compare and assess the role of fluorescent in situ hybridization (FISH) and reverse transcriptase polymerase chain reaction (RT-PCR) in the diagnosis and long-term monitoring of Acute Promyelocytic Leukemia (APL).

MATERIALS AND METHODS

We compared 145 samples received at different interval of times to analyze the sensitivity of RT-PCR and FISH.

RESULTS

The failure rate for RT-PCR was 4% at baseline, 13% at induction, and 0% at the end of consolidation. And for FISH it was 8% at baseline, 38% at induction, and 66% at the end of consolidation. The predictive values of relapse in the patients who were positive and negative by RT-PCR, at the end of induction, were 60% and 3%, respectively, and at end of consolidation it was 67% and 4%, respectively. On the other hand the predictive values of relapse in patients who were positive and negative by FISH at end of induction were 57% and 6%, respectively; while at end of consolidation it was 14% who were negative by FISH.

CONCLUSION

Both RT-PCR and FISH are important for the diagnosis of APL cases, as both techniques complement each other in the absence or failure of any one of them. However, RT-PCR is more sensitive than FISH for the detection of minimal residual disease in the long-term monitoring of these patients. The present study shows that the predictive value of relapse is more associated with minimal residual disease (MRD) results by RT-PCR than that by FISH.

The effect of age on the bacteria isolated and the antibiotic-sensitivity pattern in infections among cancer patients

BACKGROUND

Patients with cancer are predisposed to infections. Antimicrobial patterns and antibiotic sensitivity change with increasing age, making choice of empirical therapy more complicated.

MATERIALS AND METHODS

This single-center study aims to try and assess the influence of age on microbiology and antibiotic sensitivity of organisms causing infection in patients with malignant disease.

RESULTS

The five most common bacterial pathogens isolated were Pseudomonas sp (245, 26.2%) > Enterocococcus sp (109, 11.66%) > Staphylococcus aureus (107, 11.44%) > Escherichia coli (106, 11.34%) > Klebsiella sp (99, 10.59%). There was no significant change in the distribution of Gram-positive and Gram-negative bacteria with age. However, there was an increase in the occurrence of the Enterobacteriacea group and a decrease in infections caused by nonlactose fermenters with increasing age. The ESBL production increased from 10.52% (12-19 years) to 24.88% (> 50 years) as did oxacillin resistance (from 14.3% to 28.1%) among S. aureus isolates. The activity of most antimicrobial agents decreased with increasing age. The decreasing trend of activity was statistically significant for meropenam (73.3-41.2%) against Pseudomonas sp. and for the activity of the aminoglycosides for Acinetobacter sp (61.1-17.4% for amikacin).

CONCLUSIONS

This suggests that empirical antibiotic therapy needs to be changed on the basis of the age of the patient. It also appears that combination therapy is essential for the empirical treatment of infections in elderly patients with cancer.