Magnesium Hydrogen Phosphate: An Efficient Catalyst for Acrylic Acid Production from Biorenewable Lactic Acid

A series of Magnesium hydrogen phosphate (MgHP) catalysts with different magnesium to phosphorous (Mg/P) mole ratios at varying calcination temperatures has been synthesised, bearing in mind the effectiveness as well as the stability of MgHP to catalyse acrylic acid (AA) production from biorenewable lactic acid (LA), a synthetic process applicable to biomass conversion. The physicochemical properties of the MgHP catalysts have been thoroughly characterised and the formation of Mg(NH₄)PO₄, MgHPO₄ and Mg₂P₂O₇ with different structural and acidic properties have been reported. The high catalytic performance of MgHP catalysts with high AA yields (100% conversion and 85% selectivity) at high space velocities (WHSV_LA = 3.13 h^-1) have been achieved at 360 °C. NH₃-Temperature programmed desorption (TPD) and pyridine FTIR have shown that the effectiveness of a catalyst is accounted for not primarily by the actual strength of acidic sites, but is due to the presence of Lewis acidic sites compared to Bronsted sites.

Risk of lymphoma subtypes after solid organ transplantation in the United States

BACKGROUND

Solid organ transplant recipients have high risk of lymphomas, including non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). A gap in our understanding of post-transplant lymphomas involves the spectrum and associated risks of their many histologic subtypes.

METHODS

We linked nationwide data on solid organ transplants from the US Scientific Registry of Transplant Recipients (1987-2008) to 14 state and regional cancer registries, yielding 791 281 person-years of follow-up for 19 distinct NHL subtypes and HL. We calculated standardised incidence ratios (SIRs) and used Poisson regression to compare SIRs by recipient age, transplanted organ, and time since transplantation.

RESULTS

The risk varied widely across subtypes, with strong elevations (SIRs 10-100) for hepatosplenic T-cell lymphoma, Burkitt's lymphoma, NK/T-cell lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma (both systemic and primary cutaneous forms). Moderate elevations (SIRs 2-4) were observed for HL and lymphoplasmacytic, peripheral T-cell, and marginal zone lymphomas, but SIRs for indolent lymphoma subtypes were not elevated. Generally, SIRs were highest for younger recipients (<20 years) and those receiving organs other than kidneys.

CONCLUSION

Transplant recipients experience markedly elevated risk of a distinct spectrum of lymphoma subtypes. These findings support the aetiologic relevance of immunosuppression for certain subtypes and underscore the importance of detailed haematopathologic workup for transplant recipients with suspected lymphoma.

Neuroprotective effect of allopurinol and nimesulide against cerebral ischemic reperfusion injury in diabetic rats

OBJECTIVES

The main objective of the study was to determine the neuroprotective effect of allopurinol and nimesulide against the cerebral ischemic reperfusion injury in diabetic and nondiabetic rats.

MATERIALS AND METHODS

In this study, Wistar albino rats of either sex weighing 150-250 g were procured from authorized suppliers. Rats were anesthetized by giving thiopentone sodium (45 mg/kg) by i.p. Under anesthesia, midline incision was given. Common carotid arteries were identified and isolated carefully from vago-sympathetic nerve. Rats were made ischemic by occluding bicommon carotid arteries with thread for 30 min, followed by reperfusion for 4 h by removing the occlusion. The drugs allopurinol (15, 30 mg/kg) and nimesulide (20, 40 mg/kg) were administered 10 min before reperfusion. Then after 4 h reperfusion, animals were sacrificed and immediately brain was removed, homogenized, centrifuged and supernatant was collected, various enzyme estimations were done and same procedure was followed in streptozotocin (STZ: 45 mg/kg; i.p.) induced diabetic rats.

RESULTS

Ischemia reperfusion (I/R) group showed significant increase in malondialdehyde (MDA), myeloperoxidase (MPO) and depletion in catalase (CAT) and superoxide dismutase (SOD) levels. Treatment with allopurinol and nimesulide significantly decreased the MDA and MPO levels whereas increased the SOD and CAT levels when compared I/R group in both non-diabetic and diabetic rats.

CONCLUSIONS

These findings suggest the cerebral injury due to over production of free radicals was inhibited by allopurinol and nimesulide that exert a neuroprotective effect probably by radical scavenging and antioxidant activities.

Influence of education level on cancer survival in Sweden

BACKGROUND

While cancer survival at several sites has historically been shown to vary by education level, a current comprehensive assessment of survival following a cancer diagnosis in Sweden, a country with universal health care and cancer screening, has yet to be carried out.

METHODS

Using the 2006 update of the Swedish Family-Cancer Database and Cox's proportional hazards regression methods, we calculate the adjusted hazard ratio (HR) and 95% confidence interval to estimate the influence of education level on site-specific cancer survival.

RESULTS

Significant positive associations between education level and cancer survival were observed following a diagnosis of upper aerodigestive track cancer, colon cancer, pancreatic cancer, lung cancer, kidney cancer, urinary bladder cancer, melanoma, non-Hodgkin's lymphoma, breast cancer, endometrial cancer, cervical cancer, prostate cancer, and testicular cancer. Although the HRs differed between cancer sites, compared with women and men completing <9 years of education, university graduates were associated with a significant 40% improved survival for all cancer sites combined.

CONCLUSIONS

Survival differences by education level were observed for both indolent and aggressive malignancies.

Air quality status at selected locations in Hyderabad City

A case study for assessing the air quality status is elaborated for Hyderabad city. Monitoring was carried out at 11 locations during March 2003. These observations on air quality status and AQEI predicts that most of the localities in Hyderabad are experiencing the air pollution stress and the trend is likely to worsen in near future if proper control measures are not implemented.

Management of opioid-induced pruritus: a role for 5-HT3 antagonists?

We have evaluated the efficacy of ondansetron in the prevention of opioid-induced pruritus in a prospective, randomized, double-blind, placebo-controlled study. Using a 'human model' of opioid-induced pruritus, 80 ASA I-II patients about to undergo routine surgery were given either ondansetron 4 mg i.v. or 0.9% saline i.v. (40 in each group), 30 min before alfentanil 10 mg kg-1 i.v. During the following 5 min, patients were observed for signs of perinasal scratching and at 5 min were asked about symptoms of pruritus. The study was then terminated and anaesthesia was induced. There was a significant reduction in the incidence of scratching in patients receiving ondansetron compared with placebo (42.5% vs 70%, respectively, P = 0.013). The incidence of itching in the ondansetron group was less than that in the placebo group but this was not statistically significant (30% vs 42.5%, respectively, P = 0.245). We conclude that the 5-HT3 antagonist ondansetron may have a role in the management of opioid-induced pruritus.

Emergence of non-group A streptococcal necrotizing diabetic foot infections

Recently the authors have noted a disturbing trend toward an increased incidence of necrotizing infections caused by non-group A streptococcal species. This article describes the typical clinical course of such an infection. Prompt surgical intervention, coupled with an antibiotic regimen aimed at mitigating exotoxin release, may be both limb- and life-preserving.

Vibration perception threshold: are multiple sites of testing superior to single site testing on diabetic foot examination?

Vibration perception threshold (VPT) values, measured at different anatomic locations on the foot and ankle, and the time to assess VPT and sensory perception using two difference modalities in 102 diabetic patients were compared. VPT was evaluated at the great toe, fifth metatarsal and ankle. Differences in VPT at these three sites, in addition to differences in duration of testing comparing single site (great toe) to multiple sites, and to standard SWMF testing were assessed. No significant difference in VPT between the great toe and fifth metatarsal was found for patients both with and without loss of protective sensation (LOPS). Mean VPT was significantly higher at the ankle compared with both the great toes and fifth metatarsals. However, the difference between ankle and great toe was not significant between patients with and without LOPS [3.9 +/- 11.2 (12%) vs. 3.0 +/- 10.8 (16%) volts, respectively, p > 0.6]. Testing of one site took approximately half the time of Semmes-Weinstein 10-gram monofilament wire SWMF testing (40.5 +/- 16.9 vs. 22.3 +/- 9.1 seconds, p < 0.01) and less than one third the time of three-site VPT testing (10.5 +/- 26.1 vs. 22.3 +/- 9.1 seconds, p < 0.01). There may not be a significant practical benefit in multiple site VPT testing when compared with single site testing on the great toe alone. The value of multiple site testing is further called into question when one notes that the great toe VPT remains the only site tested for sensitivity and specificity for ulceration.

Epsilon-aminocaproic acid and recurrent subarachnoid hemorrhage: a clinical trial

A clinical trial of epsilon-aminocaproic acid (EACA) in preventing recurrent hemorrhage from intracranial arterial aneurysms is reported. Previous reports were reviewed, and their results concerning antifibrinolytic agents were inconclusive in establishing their efficacy. One hundred patients with documented ruptured intracranial aneurysms were admitted to this study within 48 hours of the initial hemorrhage: 45 patients received 36 gm of EACA/day, with 11 documented rebleeds and one suspected rebleed. No benefit was seen from the use of EACA.