The structural protein ODV-EC27 of Autographa californica nucleopolyhedrovirus is a multifunctional viral cyclin

Two major characteristics of baculovirus infection are arrest of the host cell at G₂/M phase of the cell cycle with continuing viral DNA replication. We show that Autographa californica nucleopolyhedrovirus (AcMNPV) encodes for a multifunctional cyclin that may partially explain the molecular basis of these important characteristics of AcMNPV (baculovirus) infection. Amino acids 80–110 of the viral structural protein ODV-EC27 (−EC27) demonstrate 25–30% similarity with cellular cyclins within the cyclin box. Immunoprecipitation results using antibodies to −EC27 show that −EC27 can associate with either cdc2 or cdk6 resulting in active kinase complexes that can phosphorylate histone H1 and retinoblastoma protein in vitro. The cdk6-EC27 complex also associates with proliferating cell nuclear antigen (PCNA) and we demonstrate that PCNA is a structural protein of both the budded virus and the occlusion-derived virus. These results suggest that −EC27 can function as a multifunctional cyclin: when associated with cdc2, it exhibits cyclin B-like activity; when associated with cdk6, the complex possesses cyclin D-like activity and binds PCNA. The possible roles of such a multifunctional cyclin during the life cycle of baculovirus are discussed, along with potential implications relative to the expression of functionally authentic recombinant proteins by using baculovirus-infected cells.     

Effects of α-adrenoceptor-stimulating drugs on baroreceptor reflexes in conscious cats

The action of some α-adrenoceptor stimulating drugs with a central effect (clonidine, α-methyldopa, reserpine) on baroreceptor reflexes was studied in conscious cats (both in the resting condition and when influenced by emotional tension or electrical stimulation of the hypothalamus). The sedative effect of these drugs was observed simultaneously with bradycardia and the increase of baroreceptor reflexes. Clonidine and reserpine (in 6–24 h after injection) lowered blood pressure while α-methyldopa (40 mg/kg) increased it. Confrontation with a dog or electrical hypothalamic stimulation produced hypertensive reactions and diminished the baroreflexes. All drugs reduced the emotional and hypertensive reactions caused by natural stress situations and restored baroreceptor reflexes. On the other hand, neither clonidine nor α-methyldopa changed the decrease of baroreceptor reflexes caused by electrical hypothalamic stimulation. It is supposed that central α-adrenoceptor stimulating drugs do not influence processes of hypothalamic modulation of baroreceptor reflexes. The increase in baroreflex activity after clonidine, α-methyldopa and reserpine appears to be due to a direct effect of the drugs on the central neurones mediating baroreceptor reflexes and to the tranquillizing action of these drugs.     

In vitro decalcification of aortic valve leaflets with the Er:YSGG laser,Ho:YAG laser,and the cavitron ultrasound surgical aspirator

This study was designed to compare the efficacy of the erbium: yttrium-scandium-gallium-garnet (Er:YSGG) laser and the holmium:yttrium-aluminum-garnet (Ho:YAG) lasers in debriding calcium from freshly explanted aortic valve leaflets and to compare the Er:YSGG laser with the Cavitron ultrasonic surgical aspirator (CUSA). Aortic valve leaflets were freshly explanted from patients undergoing aortic valve replacement for aortic stenosis. Initially, 4 leaflets each were debrided with the Er:YSGG and the Ho:YAG lasers to attempt removal of calcium deposits while preserving the underlying integrity of the leaflets and minimizing thermal damage. The Er:YSGG laser was more effective in doing so with less thermal and photoacoustic damage when compared with the Ho:YAG laser. Twelve more leaflets each were then debrided with the Er:YSGG laser and the CUSA. The Er:YSGG laser again proved less injurious to the underlying leaflet. The CUSA-treated leaflets demonstrated shattering and disruption of adjacent tissue as well as collagen fiber exposure. These changes were not seen with the Er:YSGG laser. Because of these properties, the Er:YSGG laser merits further evaluation as a tool for aortic valvuloplasty procedures in selected patients with senescent calcific aortic stenosis. © 1993 Wiley-Liss, Inc.     

Serum immunoglobulins in colorectal cancer

Preoperative serum immunoglobulins were measured in 102 patients with colorectal carcinoma. There were no differences in the mean values of IgA, IgM or IgG between stages. There was an association, however, between advanced stage of disease and a combination of low levels of IgA (≤200 mg/dl) or high levels of IgM (≥125 mg/dl). The ratio of IgA/IgM was also found to be lower in advanced disease. It was felt that low levels of IgA and high IgM may represent an altered immune response and thus be a prognostic indicator.     

Diagnostic value of 123I-IMT SPECT in the follow-up of head and neck cancer

BACKGROUND: Nuclear medicine imaging is increasingly used in the evaluation of tumors of the head and neck. In the current study, we assess the value of single-photon emission tomography (SPECT) using the amino acid tracer L-3-[123I]iodine-alpha-methyl-tyrosine (IMT) for the detection of recurrent head and neck cancer. PATIENTS AND METHODS: 45 consecutive patients with suspected recurrence of previously treated head and neck cancer were examined by IMT-SPECT using a dual head system with integrated low-dose computed tomography (CT). The accuracy of the IMT-SPECT was evaluated by correlating the findings with results of histology or clinical and CT/MRI (magnetic resonance imaging) follow-up examinations. RESULTS: The sensitivity, specificity and accuracy of IMT-SPECT in the detection of recurrent/persistent tumors were 83, 89 and 84.5%, respectively. The positive and negative predictive value amounted to 96.5 and 60%, respectively. CONCLUSION: IMT-SPECT using integrated low-dose CT appears to be a helpful complementary imaging tool for the detection of local recurrences and lymph node metastases of head and neck cancer and their differentiation from treatment-induced changes. The advantage of the method is the high positive predictive value in the diagnosis of relapsed tumors. However, a negative IMT-SPECT result does not exclude a recurrence.     

Alternative bi-pectoral muscle flaps for postoperative sternotomy mediastinitis

Suppuration, mediastinitis, and disruption of median sternotomy are all rare, but nevertheless severe complications. We propose a simple mobilization of the two pectoralis major muscles for use as flaps to fill the sternal defect without the need for humeral detachment or a second cutaneous incision. These will be supplied from both the thoracoacromial vessels and the perforating arteries of the nongrafted internal mammary artery (IMA). Our technique is quick and easy, giving excellent results. Furthermore, by maintaining the perforating branches, we also preserve the nongrafted IMA.     

Use of cancer‐specific genomic rearrangements to quantify disease burden in plasma from patients with solid tumors

Detection of recurrent somatic rearrangements routinely allows monitoring of residual disease burden in leukemias, but is not used for most solid tumors. However, next‐generation sequencing now allows rapid identification of patient‐specific rearrangements in solid tumors. We mapped genomic rearrangements in three cancers and showed that PCR assays for rearrangements could detect a single copy of the tumor genome in plasma without false positives. Disease status, drug responsiveness, and incipient relapse could be serially assessed. In future, this strategy could be readily established in diagnostic laboratories, with major impact on monitoring of disease status and personalizing treatment of solid tumors. © 2010 Wiley‐Liss, Inc.