Use of smoke-less tobacco amongst the staff of tertiary care hospitals in the largest city of Pakistan

Background: Use of smoke-less tobacco (SLT) is very common in South and South-East Asian countries. It issignificantly associated with various types of cancers. The objectives of this study were to assess the proportionof hospital staff that use SLT, and to identify the factors associated with its use and their practices. Methods: Ina cross-sectional study, 560 staff of two tertiary care hospitals were interviewed in the year 2009. Nurses, wardboys and technicians were counted as a paramedic staff while drivers, peons, security guards and housekeepingstaff were labeled as non-paramedic staff. SLT use was considered as usage of any of the following: betel quid(paan) with or without tobacco, betel nuts with or without tobacco (gutkha) and snuff (naswar). Results: Abouthalf (48.6%) of the hospital staff were using at least one type of SLT. Factors found to be statistically significantwith SLT were being a male (OR=2.5; 95% CI=1.8-3.7); having no/fewer years of education (OR=1.7; 95%CI=1.2-2.4) and working as non-paramedic staff (OR=2.6; 95% CI=1.8-3.8). Majority of SLT users were usingit on regular basis, for > 5 years and keeping the tobacco products in the oral cavity for >30 minutes. About halfof the users started due to peer pressure and had tried to quit this habit but failed. Conclusion: In this study,about half of the study participants were using SLT in different forms. We suggest educational and behavioralinterventions for control of SLT usage.     

Poly(lactic acid-glycolic acid) nanoparticles markedly improve immunological protection provided by peptide P10 against murine paracoccidioidomycosis

Background and purpose:

The present study reports on the preparation and testing of a sustained delivery system for the immunomodulatory peptide P10 aimed at reducing the in vivo degradation of the peptide and the amount required to elicit a protective immune response against paracoccidioidomycosis.

Experimental approach:

BALB/c mice were infected with the yeast Paracoccidioides brasiliensis to mimic the chronic form of paracoccidioidomycosis. The animals were treated daily with sulfamethoxazole/trimethoprim alone or combined with peptide P10, either emulsified in Freund''s adjuvant or entrapped in poly(lactic acid-glycolic acid) (PLGA) nanoparticles at different concentrations (1 µg, 5 µg, 10 µg, 20 µg or 40 µg·50 µL⁻¹). Therapeutic efficacy was assessed as fungal burden in tissues and the immune response by quantitative determination of cytokines.

Key results:

Animals given combined chemotherapy and P10 nanotherapy presented a marked reduction of fungal load in the lungs, compared with the non-treated animals. After 30 days of treatment, P10 entrapped within PLGA (1 µg·50 µL⁻¹) was more effective than ‘free’ P10 emulsified in Freund''s adjuvant (20 µg·50 µL⁻¹), as an adjuvant to chemotherapy. After treatment for 90 days, the higher doses of P10 entrapped within PLGA (5 or 10 µg·50 µL⁻¹) were most effective. Treatment with P10 emulsified in Freund''s adjuvant (20 µg·50 µL⁻¹) or P10 entrapped within PLGA (1 µg·50 µL⁻¹) were accompanied by high levels of interferon-gamma in lung.

Conclusions and implications:

Combination of sulfamethoxazole/trimethoprim with the P10 peptide entrapped within PLGA demonstrated increased therapeutic efficacy against paracoccidioidomycosis. P10 incorporation into PLGA nanoparticles dramatically reduced the peptide amount necessary to elicit a protective effect.     

Alkaline Phosphatase of Cancerous Larynx Tissue in Comparison with the Placental Enzyme: Biochemical and Histochemical Studies

Tissue specimens of squamous cell carcinoma of the larynx from twenty patients were processed for histological and histopathological characterization. A histochemical study of alkaline phosphatase (ALP) was carried out using the simultaneous azo coupling method, and biochemical studies were performed using disodium phenylphosphate as substrate. Full-term, normal placentae were used for comparison. The specific activity of ALP from cancerous laryngeal tissue was 8.9 mKAU/mg protein compared with 154.7 mKAU/mg protein in the placenta. The ALP was localized histochemically in tumor cells (tumor-specific), blood vessels (vascular) and fibrous tissue (interstitial). The tumor-specific phosphatase was sensitive to inhibition by L-phenylalanine, L-leucine and to a lesser degree by L-tryptophan and levamisole. Placental ALP, on the other hand, was completely inhibited by levamisole, more resistant to leucine and more sensitive to phenylalanine and tryptophan. Biochemical estimation of ALP in cancerous laryngeal tissue combined with inhibition studies revealed that the tumor-specific activity of ALP constitutes 15% of the total ALP activity while the major isoenzyme was the vascular ALP, and around one-third of ALP activity was attributed to the interstitial enzyme. The characterization and localization of these isoenzymes are described and compared with that of the placenta. The significance and implications of the above findings are presented.     

Effect of two phenanthrene alkaloids on angiotensin II-induced leukocyte-endothelial cell interactions in vivo

1. The present study has evaluated the effect of two phenanthrene alkaloids, uvariopsine and stephenanthrine, on angiotensin II (Ang-II)-induced leukocyte-endothelial cell interactions in vivo and the mechanisms involved in their activity. Intravital microscopy within the rat mesenteric microcirculation was used. 2. A 60 min superfusion with 1 nm Ang-II induced a significant increase in the leukocyte-endothelial cell interactions that were completely inhibited by 1 microm uvariopsine cosuperfusion. A lower dose of 0.1 microm significantly reduced Ang-II-induced leukocyte adhesion by 75%. 3. When Ang-II was cosuperfused with 1 and 0.1 microm stephenanthrine, Ang-II-induced leukocyte responses were significantly diminished. A lower dose of 0.01 microm only affected Ang-II-induced leukocyte adhesion. 4. Both alkaloids inhibited Ang-II-induced endothelial P-selectin upregulation and the generation of reactive oxygen species (ROS) in endothelial cells stimulated with Ang-II, in fMLP-stimulated human neutrophils (PMNs) and in the hypoxanthine-xanthine oxidase system. However, cyclic AMP levels in PMNs stimulated with fMLP were not affected. 5. Uvariopsine and stephenanthrine inhibited PAF-induced elevations in intracellular calcium levels in PMNs (IC50 values: 15.1 and 6.1 microm respectively) and blocked the binding of [3H]PAF to these leukocytes. They also reduced PAF-induced increases in intracellular levels of superoxide anion and hydrogen peroxide. 6. In conclusion, stephenanthrine and uvariopsine are potent inhibitors of Ang-II-induced leukocyte accumulation in vivo. This effect appears to be mediated through ROS scavenging activity and blockade of PAF receptor. Thus, they have potential therapeutic interest for the control of leukocyte recruitment that occurs in cardiovascular disease states in which Ang-II is involved.     

Efficient biomass saccharification using a novel cellobiohydrolase from Clostridium clariflavum for utilization in biofuel industry

The present study describes the cloning of the cellobiohydrolase gene from a thermophilic bacterium Clostridium clariflavum and its expression in Escherichia coli BL21(DE3) utilizing the expression vector pET-21a(+). The optimization of various parameters (pH, temperature, isopropyl β-d-1-thiogalactopyranoside (IPTG) concentration, time of induction) was carried out to obtain the maximum enzyme activity (2.78 ± 0.145 U ml⁻¹) of recombinant enzyme. The maximum expression of recombinant cellobiohydrolase was obtained at pH 6.0 and 70 °C respectively. Enzyme purification was performed by heat treatment and immobilized metal anionic chromatography. The specific activity of the purified enzyme was 57.4 U mg⁻¹ with 35.17% recovery and 3.90 purification fold. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the molecular weight of cellobiohydrolase was 78 kDa. Among metal ions, Ca²⁺ showed a positive impact on the cellobiohydrolase enzyme with increased activity by 115%. Recombinant purified cellobiohydrolase enzyme remained stable and exhibited 77% and 63% residual activity in comparison to control in the presence of n-butanol and after incubation at 80 °C for 1 h, respectively. Our results indicate that our purified recombinant cellobiohydrolase can be used in the biofuel industry.

Successful expression of a novel cellobiohydrolase enzyme from Clostridium clariflavum with efficient saccharification potential of plant biomass for the biofuel industry.     

Oculomotor nerve palsy in neurofibromatosis type 2

Neurofibromatosis (NF) type 2 is a rare neurological, autosomal dominant and genetic disorder. It is caused by a mutation in the tumor suppressor gene, called NF2 gene. The disorder results in several benign tumors of the nervous system. These typically include vestibular schwannomas, meningiomas, and ependymomas. Multiple cranial nerve abnormalities affect the brain, spinal cord, nerves, and skin and cause significant morbidity in patients. We describe a 20-year-old patient, with a family history of brain tumors, with symptoms of left sided third nerve palsy. Magnetic Resonance Imaging (MRI) of the brain and orbits revealed a small sized cavernous sinus meningioma and bilateral vestibular schwannomas. As per the differential diagnosis and optimal resolution brain imaging, NF2 was diagnosed. The patient was referred for specific treatment to the neuro-oncology unit. The case is distinct as the patient presented with a parasellar meningioma leading to third nerve palsy besides bilateral vestibular schwannomas. Manchester criteria and high contrast MR imaging proved more beneficial in our patient for the diagnosis of a wider clinical spectrum of NF2.     

Polymethacrylate Microparticles Gel for Topical Drug Delivery

Purpose  

Evaluating the potentials of particulate delivery systems in topical drug delivery.