Striatal delivery of CERE-120, an AAV2 vector encoding human neurturin, enhances activity of the dopaminergic nigrostriatal system in aged monkeys.

Neurturin (NTN) is a potent survival factor for midbrain dopaminergic neurons. CERE-120, an adeno-associated virus type 2 (AAV2) vector encoding human NTN (AAV2-NTN), is currently being developed as a potential therapy for Parkinson's disease. This study examined the bioactivity and safety/tolerability of AAV2-NTN in the aged monkey model of nigrostriatal dopamine insufficiency. Aged rhesus monkeys received unilateral injections of AAV2-NTN into the caudate and putamen, with each animal therefore serving as its own control. Robust expression of NTN within the nigrostriatal system was observed 8 months postadministration. (18)F-fluorodopa imaging using positron emission tomography revealed statistically significant increases in (18)F-fluorodopa uptake in the injected striatum compared with the uninjected side at 4 and 8 months. In addition, at 8 months postadministration, a significant enhancement in tyrosine hydroxylase immunoreactive fibers and an increase in the number of tyrosine hydroxylase immunoreactive cells was observed in the AAV2-NTN injected striatum compared with the uninjected side. Robust activation of phosphorylated extracellular signal-regulated kinase immunoreactivity in the substantia nigra was also observed. Histopathological analyses revealed no adverse effects of AAV2-NTN in the brain. Collectively, these results are consistent with the neurotrophic effects of NTN on the dopaminergic nigrostriatal system and extend the growing body of evidence supporting the concept that AAV2-NTN may have therapeutic benefit for Parkinson's disease.     

Nicotine induces calcium spikes in single nerve terminal varicosities: a role for intracellular calcium stores

We have previously shown that a large part of the D-amphetamine-induced release of dopamine in the nucleus accumbens is not associated with an increase in locomotor activity, and that "functional" dopamine release (i.e. release of dopamine associated with locomotor activity) requires the distal facilitation of noradrenergic transmission through alpha1-adrenergic receptors in the prefrontal cortex. To determine the role of monosynaptic or polysynaptic projections from the prefrontal cortex to the nucleus accumbens in these amphetamine responses, either AMPA/kainate (6-cyano-7-nitroquinoxaline-2,3-dione, CNQX, 300microM), N-methyl-D-aspartate (D(-)-2-amino-5-phosphono-pentanoic acid, APV, 500microM) or metabotropic [(+)-alpha-methyl-4-carboxy-phenylglycine, MCPG, 10mM] glutamate receptor antagonists were infused through a dialysis probe in the rat nucleus accumbens. CNQX and MCPG but not APV reduced the "non-functional" release of dopamine evoked by local (3microM) and systemic D-amphetamine (2mg/kg i.p.) treatments. However, the locomotor hyperactivity and functional dopamine release induced by systemic D-amphetamine were abolished by MCPG, but neither by CNQX nor by APV. MCPG treatment also abolished the hyperlocomotor activity and functional dopamine release evoked by bilateral morphine injection into the ventral tegmental area. The dopamine release evoked by this morphine treatment was 16-fold lower than that induced by the systemic D-amphetamine injection, although similar behavioral activations were observed. Altogether, our results further aid the discrimination of functional and non-functional release of dopamine. We suggest that the activation of metabotropic glutamate receptors in the nucleus accumbens is required for functional dopamine release following systemic D-amphetamine injection.     

Interaction of polystyryl radical with copper(II) complexes

The polymerization of styrene initiated by 2,2′-azoisobutyronitrile (AIBN) was studied in N,N-dimethylformamide (DMF) solution at 60°C in the presence of tetrakis(N,N-dimethylformamide)copper(II) perchlorate, and also in the presence of its monoazido copper(II) complex [Cu(DMF)₃N₃]⁺. The monoazido complex in DMF was prepared in situ by mixing solid sodium azide with tetrakis(N,N-dimethylformamide)copper(II) perchlorate in a mole ratio of 1:1. The nature of the complex was established by Job's method. The equilibrium constant K for the reaction [Cu(DMF)₄]²⁺ + N ? [Cu(DMF)₃N₃]⁺ + DMF determined by the limiting logarithmic method was found to be 1,25 · 10⁴l · mol^?1. The presence of [Cu(DMF)₄]²⁺ ions in the polymerization systems caused retardation, but [Cu(DMF)₃N₃]⁺ ions produced well defined induction periods. The rate constants at 60°C for the interaction of polystyryl radical towards [Cu(DMF)₄]²⁺ and [Cu(DMF)₃N₃]⁺ ions were calculated to be 6,6 · 10² and 5,74 · 10⁴ l · mol^?1 · s^?1, respectively.     

Randomized, double-blind, placebo-controlled study of montelukast for treating perennial allergic rhinitis.

BACKGROUND: Perennial allergic rhinitis (PAR) is a persistent allergic inflammation of the upper respiratory tract due to year-round allergen exposure. OBJECTIVE: To evaluate the leukotriene receptor antagonist montelukast for the treatment of PAR. METHODS: Protocol 265 was a 2-arm study performed during the winter. After a placebo run-in period, adults with perennial allergen sensitivity and active symptoms of PAR were randomized to receive 10 mg of montelukast (n=1002) or placebo (n=990) once daily during a 6-week, double-blind, active-treatment period. The primary end point was the daytime nasal symptoms score, defined as the average of scores for nasal congestion, rhinorrhea, and sneezing rated daily by patients. RESULTS: Statistically significant improvements in PAR symptoms were seen in patients treated with montelukast. Their daytime nasal symptoms scores were reduced during treatment compared with those of the placebo group: the difference between treatments in least squares mean change from baseline was -0.08 (95% confidence interval [CI], -0.12 to -0.04; P < .001). Montelukast treatment also improved global evaluations of allergic rhinitis by patients and Rhinoconjunctivitis Quality of Life Questionnaire scores: differences vs the placebo group were -0.15 (95% CI, -0.27 to -0.04; P < .01) and -0.15 (95% CI, -0.24 to -0.06; P < .001), respectively. Other end points that showed statistically significant improvement with montelukast treatment were nighttime symptoms and each of the 4 nasal symptoms (congestion, rhinorrhea, sneezing, and itching). The treatment effects of montelukast were stable and persistent during the entire 6 weeks of treatment. CONCLUSION: Montelukast provided statistically significant relief of PAR symptoms during 6 weeks of treatment.     

Effect of gossypol in association with chromium protoporphyrin on heme metabolic enzymes

Gossypol prevents the liberation of oxygen from oxyhemoglobin and exerts a hemolytic effect on erythrocytes. In excessive dosages of gossypol, an extreme burden is placed upon the respiratory and circulatory organs owing to the reduced oxygen carrying capacity of blood. Chromium protoporphyrin (CrPP) has been shown to either competitively suppress or to significantly ameliorate a variety of naturally occurring or experimentally induced forms of jaundice in animals and man. In this communication, a novel tissue dependent response to gossypol (50 micromol/kg bw) and gossypol in association with CrPP (50 micromol/kg bw) is described. Our results revealed that gossypol stimulated the hepatic, splenic, and renal delta-aminolevulinic acid synthase (ALA-S) activity, the heme biosynthetic enzyme, and simultaneous administration of CrPP and gossypol synergized the gossypol-mediated increase of ALA-S activity. Gossypol was found to be a potent stimulator of heme oxygenase (HMOX) activity in rat liver and kidney to varying degrees. This tissue response contrasted with that of the spleen, where gossypol decreased the activity of the enzyme. In consonance with the increased hepatic and renal HMOX activity, a marked increase was observed in total serum bilirubin concentration in gossypol treated rats. When rats were given CrPP simultaneously with gossypol, the gossypol mediated increase in hepatic and renal HMOX activity was effectively blocked. Furthermore, the increase in enzymatic activity was accomplished by a decline in the total microsomal protein content on gossypol administration. These findings emphasize the toxic effect of gossypol in eliciting increased heme degradation by stimulating HMOX activity in the liver and the kidney and the potential usefulness of CrPP in experimental and perhaps clinical conditions in which hyperbilirubinemia occurs.     

gamma-Glutamyl transpeptidase activity in Ascaris suum

Using histochemical techniques γ-glutamyl transpeptidase activity has been localized mainly in the cuticle-hypodermis in Ascaris suum. The specific activity of γ-glutamyl transpeptidase was 3.87 ± 0.49 μmol h⁻¹ (g tissue)⁻¹ in cuticle-hypodermis as compared to gastrointestinal tract, where it was 0.07 ± 0.02 μmol h⁻¹ (g tissue)⁻¹, and muscle and reproductive tract where it was <0.001 μmol h⁻¹ (g tissue)⁻¹. When cuticle sections were incubated with labelled glutamine a large portion of the glutamine nitrogen was recovered as ammonia which indicated glutamine uptake and utilization by the cuticle-hypodermis. Collectively these histochemical and biochemical data support the fact that γ-glutamyl transpeptidase activity is found in the cuticle-hypodermis of A. suum and this may be an indication that amino acid absorption could occur through the cuticle via the γ-glutamyl cycle.     

Basaloid squamous cell carcinoma - larynx

Basaloid squamous cell carcinoma is a rare variant of squamous cell carcinoma, Larynx has been an uncommon site of this tumour which is said to have aggressive biological behaviour with high incidence of cervical and distant metastasis along with second primary. Two cases of laryngeal basaloid squamous cell carcinoma are reported with relevant review of literature. The submucosal spread of tumour is highlighted alongwith role of preoperative radio therapy.     

Tracheoesophageal fistula: New option in management

Tracheoesophageal fistula is a life threatening condition. Patients not managed surgically ultimately die of their disease. Surgical management is the treatment of choice. We present a case of a patient that developed a tracheoesophageal fistula after tracheostomy. Surgical repair was done which failed due to infection. The patient was managed with the help of an esophageal stent and Trichloroacetic Acid cautery. This approach can be used in selected patients, depending upon the size and site of TEE Larger fistulae and those situated lower down e.g. supra carinal cannot be managed by this technique.     

The potential role of free chitosan in bone trauma and bone cancer management

Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management.     

Chemosensitization of Solid Tumors by Inhibition of Bcl-xL Expression Using DNAzyme

DNAzymes are a novel class of gene suppressors that selectively bind to an RNA substrate by Watson-Crick base pairing and cleave phosphodiester bonds. To explore the potential for therapeutic use of catalytic DNA molecules, active DNAzymes targeting the bcl-xL gene were generated through a multiplex in vitro selection. The DNAzyme-mediated down-regulation of the bcl-xL expression was demonstrated in various cancer cell lines by Western blots. Treatment of the cells with the active DNAzyme led to increases in percentage of apoptotic cells and cytochrome c release from mitochondria, a hall marker of apoptosis. When combined with chemotherapeutics such as Taxol, the DNAzyme significantly sensitised a panel of cancer cells to apoptosis as measured by cell survival assay. In Taxol-resistant cells, down-regulation of bcl-xL expression by the DNAzyme reversed the chemo-resistant phenotype of the cancer cells. In a xenograft mouse model, the DNAzyme was delivered into the tumors via an ALZET osmotic pump and shown to chemosensitize PC3 tumor when treating with Taxol. The results from the present study demonstrate that bcl-xL DNAzyme treatment facilitates apoptosis in solid tumors and suggest the potential use of bcl-xL DNAzyme in combination with chemotherapeutics for cancer therapy.