Assessment of cancer immunotherapy outcome in terms of the immune response time features.

A cytokine-based periodic immunotherapy treatment is included in a model of tumour growth with a delay. The effects of dose schedule are studied in the case of a weak immune system and a growing tumour. We find the existence of 'metastable' states (that may last for tens of years) induced by the treatment and also potentially adverse effects of the dosage frequency on the stabilization of the tumour. These two effects depend on the delay between the tumour growth and the immune system response, the cytokine dose burden, and other parameters considered in the model.     

New evidence from magnetic resonance imaging of brain changes after climbs at extreme altitude

The aim of the present study was to look for anatomical changes in climbers' brains, using magnetic resonance imaging (MRI), after extremely high-altitude climbs and to relate them to possible associated risk factors. Clinical history, neurological examinations and MRI were carried out on a group of nine climbers before and after climbing to over 7500 m without the use of supplementary oxygen. None of the subjects showed any neurological dysfunctions. In five climbers MRI abnormalities (high signal areas, cortical atrophy) were observed before the expedition. After the descent, two of them showed new high intensity signal areas recorded by MRI. Both subjects suffered severe neurological symptoms during the climb. The present study suggested that the brain changes observed by MRI could be related to the severity of clinical events at high altitude. However, we do not know the exact meaning of such MRI findings or the reason for their location, predominantly in posterior regions of the brain. The new evidence that a high percentage of climbers show MRI brain abnormalities, and especially the appearance of changes after the ascent, reinforces the possibility of a potential neurological risk in high-altitude climbing.     

Inhibition of poly(ADP-ribose) polymerase attenuates the severity of acute pancreatitis and associated lung injury

The severity of acute pancreatitis results from the transmigration and activation of leukocytes within the pancreas and the local synthesis and release of proinflammatory-soluble mediators that transform a local injury into a systemic inflammatory response. Poly(ADP-ribose)polymerase-1 (PARP-1) is a nuclear DNA-binding protein that has been shown to play a relevant role in cell necrosis and organ failure in various diseases associated with inflammation. Therefore, we set out to investigate whether the genetic deletion of PARP-1 or PARP-2 (a new member of the PARP family) genes, or pharmacological inhibition of PARP activity might affect the development and severity of acute pancreatitis and pancreatitis-associated lung injury. Secretagogue-induced acute pancreatitis was achieved by 12 hourly intraperitoneal injections of cerulein in mice deficient in PARP-1 or PARP-2 genes, and wild-type (WT) littermate mice untreated or treated with PARP activity inhibitors. The severity of pancreatitis was assessed by measurements of serum amylase, lipase, interleukin-1beta and IL-6, pancreatic water content, histologic grading and pancreas myeloperoxidase (MPO) activity. Lung injury was evaluated by quantifying MPO activity and morphological changes. We found that the severity of acute pancreatitis and pancreatitis-associated lung injury was significantly attenuated in mice lacking PARP-1, but not PARP-2, compared with WT mice. Interestingly, administration of PARP inhibitors, 3-aminobenzamide or PJ34 (N-(6-oxo-5,6-dihydro-phenanthridin-2-yl)-N,N-dimethyacetamide HCl), in WT mice markedly decreased acute pancreatitis severity and pulmonary-associated injury in a larger extension than genetic deletion of PARP-1. Our results support the potential therapeutic application of PARP inhibitors in the development and severity of acute pancreatitis and associated lung injury.     

Molecular characterization of a carnation etched ring virus isolate from India

Incidence of the Carnation etched ring virus (CERV), the only DNA virus reported to date on carnation, was investigated by a bioassay using a partially purified virus as inoculum and then by a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Out of 61 carnation cultivars analyzed 41 (67%) were found positive. The virus positivity was verified by polymerase chain reaction (PCR) and nucleotide sequencing. The amplified 1349 bp fragment was by about 98% and 96% identical with respect to coat protein (CP) and enzymatic polyprotein genes, respectively, as compared to the sequences available in the database. In terms of amino acid sequence similarity, the homology values were 99% and 97%, respectively. Comparison with other caulimoviruses revealed that CERV is most closely related to the Cauliflower mosaic virus (CaMV). High genetic stability of CERV may be attributed to the fact that it has evolved from the same initial sequence in an original host. Because of global market of cut flowers and vegetative propagation it has been dispersed around the world.     

Cytopathology of uncommon malignant renal neoplasms in the pediatric age group

Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy.     

Neuroprotection in glaucoma

Currently, glaucoma is recognised as an optic neuropathy. Selective death of retinal ganglion cells (RGC) is the hallmark of glaucoma, which is also associated with structural changes in the optic nerve head. The process of RGC death is thought to be biphasic: a primary injury responsible for initiation of damage that is followed by a slower secondary degeneration related to noxious environment surrounding the degenerating cells. For example, retinal ishaemia may establish a cascade of changes that ultimately result in cell death: hypoxia leads to excitotoxic levels of glutamate, which cause a rise in intra-cellular calcium, which in turn, leads to neuronal death due to apoptosis or necrosis. Neuroprotection is a process that attempts to preserve the cells that were spared during the initial insult, but are still vulnerable to damage. Although not yet available, a neuroprotective agent would be of great use in arresting the progression of glaucoma. There is evidence that neuroprotection can be achieved both pharmacologically and immunologically. Pharmacological intervention aims at neutralising some of the effects of the nerve-derived toxic factors, thereby increasing the ability of the spared neurons to cope with stressful conditions. On the other hand, immunological interventions boost the body's own repair mechanisms for counteracting the toxic effects of various chemicals generated during the cascade. This review, based on a literature search using MEDLINE, focuses on diverse cellular events associated with glaucomatous neurodegeneration, and discusses some pharmacological agents believed to have a neuroprotective role in glaucoma.     

A high-performance liquid chromatography-tandem mass spectrometric method for the determination of pharmacokinetics of ganaxolone in rat, monkey, dog and human plasma

A method for determining concentration levels of ganaxolone in rat, monkey, dog and human plasma was validated in the range of 5-1500 ng/ml using a 200-microl plasma sample volume. This validation report describes the linearity, specificity. sensitivity, reproducibility, accuracy, recovery and stability of the analytical method. The inter-day C.V. ranged from 0.5 to 9.2%, intra-day C.V. from 0.7 to 8.8% and intra-day accuracy (mean absolute percentage difference) ranged from 0.0 to 14.0% for rat, monkey, dog and human plasma. The method was used for the routine analysis of ganaxolone in rat, monkey, dog and human plasma and summary of the pharmacokinetic data are presented.