Case of Chronic Lymphocytic Leukemia with Unusual Chromosome Aberrations

Chronic lymphocytic leukemia is one of the most common leukemias in the western world and consists of many chromosome aberrations. We report the case of a 74-year-old male patient with chronic lymphocytic leukemia with complex variant translocations t(8;22)(q24;q11) and der(8)t(6;8)(p21;p21) identified by chromosome banding analysis and confirmed by fluorescence in situ hybridization analysis of interphase cells. Because of the rarity of these changes, possible molecular mechanisms associated with this karyotype are discussed.     

Long-term health-related quality of life after pancreatic resection for malignancy in patients with and without severe postoperative complications

Background

Surgery for pancreatic cancer yields significant morbidity and mortality risks and survival is limited. Therefore, the influence of complications on quality of life (QoL) after pancreatic surgery is important. This study compares QoL in patients with and without severe complications after surgery for pancreatic (pre-)malignancy.

Detection of chymase activity using a specific peptide probe conjugated onto gold nanoparticles

Gold nanoparticles (AuNPs) can be applied in biosensors using fluorescence resonance energy transfer (FRET) technique. Based on this technique, we have established a sensitive and efficient biosensing method by modifying a peptide-probe onto AuNPs to detect proteinase enzyme activity in this study. This biosensing method was designed for chymase activity detection and applied in kidney disease diagnosis. In this study, 16 nm-AuNPs were used to construct the AuNPs-based fluorescence peptide probe (named AuNPs-peptide probe) for chymase activity determination. The peptide sequence is FITC-Acp-DRVYIHPFHLDDDDDC, which comprises a fluorophore at the N-terminal end, an enzyme (chymase) substrate (DRVYIHPFHL), a spacer (DDDDD) and cysteine (C) to conjugate to AuNPs surface. When the enzyme catalyzes the substrate sequence, the fluorophore drifts away from AuNPs and the fluorescence emitting signal can be excited at 495 nm and detected at 515 nm. The results indicate that the time required for the AuNPs-peptide probe for activity detection of chymase was only 15 min, and a linear correlation from 10 to 100 ng mL⁻¹ of chymase was acquired. The chymase reaction would be significantly inhibited by addition of specific chymase inhibitor chymostatin. The AuNPs-peptide probe was tested for the detection of high concentrations of trypsin and chymotrypsin, but only minor emitted fluorescence intensity was detected. According to these results, sensitivity and specificity of the AuNPs-peptide probe for chymase detection have been confirmed. AuNPs-peptide probe was successfully used for the detection of renal chymase activity; and the results indicate the pathogenically increased chymase activity in kidney tissue of nephropathic mice from aristolochic acid I treatment.

The gold nanoparticles (AuNPs) peptide probe functionalized with specific peptide sequences was developed for the sensitive and efficient detection of chymase activity.     

Over-the-wire US catheter probe as an adjunct to ERCP in the detection of choledocholithiasis

BACKGROUND: Intraductal ultrasound (IDUS) as an adjunct to ERCP for detection of extrahepatic bile duct stones is technically easy, accurate, and safe. This prospective study evaluated IDUS with an "over-the-wire" catheter US probe as an adjunct to ERCP. METHODS: Sixty-five patients, highly suspected to have choledocholithiasis, underwent IDUS during ERCP. The IDUS probe was inserted by means of the duodenoscope into the bile duct without performing a sphincterotomy. All stones identified by IDUS or retrograde cholangiography were removed with either a basket or retrieval balloon after endoscopic sphincterotomy. RESULTS: The final diagnosis was choledocholithiasis in 59 patients. Bile duct diameter ranged from 0.6 to 2.3 cm and stone size from 2 mm to 2 cm. IDUS successfully identified all stones in these patients. IDUS resulted in 2 false-positive diagnoses in the remaining 6 patients without stones (overall accuracy 97%, sensitivity 100%, specificity 67%). Cholangiography detected stones in 55 of the patients with stones (accuracy 94%, sensitivity 93%, specificity 100%). CONCLUSION: IDUS, a safe, technically easy procedure, is highly accurate in the detection of extrahepatic bile duct stones regardless of the diameter of the bile ducts. The "over-the-wire" technique preserves access to the cannulated duct. IDUS is an excellent adjunct to ERCP for the diagnosis of choledocholithiasis. IDUS differentiates stones from air bubbles and prevents unnecessary sphincterotomy.     

Primary tumor cells of myeloma patients induce interleukin-6 secretion in long-term bone marrow cultures

Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.     

GPCR dimerization in brainstem nuclei contributes to the development of hypertension

Background and Purpose

μ-Opioid receptors, pro-opiomelanocortin and pro-enkephalin are highly expressed in the nucleus tractus solitarii (NTS) and μ receptor agonists given to the NTS dose-dependently increased BP. However, the molecular mechanisms of this process remain unclear. In vitro, μ receptors heterodimerize with α_2A-adrenoceptors. We hypothesized that α_2A-adrenoceptor agonists would lose their depressor effects when their receptors heterodimerize in the NTS with μ receptors.

Experimental Approach

We microinjected μ-opioid agonists and antagonists into the NTS of rats and measured changes in BP. Formation of μ receptor/α_2A-adrenoceptor heterodimers was assessed with immunofluorescence and co-immunoprecipitation methods, along with proximity ligation assays.

Key Results

Immunofluorescence staining revealed colocalization of α_2A-adrenoceptors and μ receptors in NTS neurons. Co-immunoprecipitation revealed interactions between α_2A-adrenoceptors and μ receptors. In situ proximity ligation assays confirmed the presence of μ receptor/α_2A-adrenoceptor heterodimers in the NTS. Higher levels of endogenous endomorphin-1 and μ receptor/α_2A-adrenoceptor heterodimers were found in the NTS of hypertensive rats, than in normotensive rats. Microinjection of the μ receptor agonist [D-Ala², MePhe⁴, Gly⁵-ol]-enkephalin (DAMGO), but not that of the α_2A-adrenoceptor agonist guanfacine, into the NTS of normotensive rats increased μ receptor/α_2A-adrenoceptor heterodimer formation and BP elevation. The NO-dependent BP-lowering effect of α_2A-adrenoceptor agonists was blunted following increased formation of μ receptor/α_2A-adrenoceptor heterodimers in the NTS of hypertensive rats and DAMGO-treated normotensive rats.

Conclusions and Implications

Increases in endogenous μ receptor agonists in the NTS induced μ receptor/α_2A-adrenoceptor heterodimer formation and reduced the NO-dependent depressor effect of α_2A-adrenoceptor agonists. This process could contribute to the pathogenesis of hypertension.