Artery of Percheron infarction presenting as nuclear third nerve palsy and transient loss of consciousness: a case report.

BACKGROUND: Thalamic blood supply consists of four major vascular territories. Out of them paramedian arteries supply ipsilateral paramedian thalami and occasionally rostral mid brain. Rarely both paramedian arteries arise from a common trunk that arise from P1 segment of one sided posterior cerebral artery (PCA). This is usually due to hypoplastic or absent other P1 and this common trunk is termed Artery of Percheron (AOP). Its prevalence is in the range of 7-11% among the general population and AOP infarcts account in an average of 0.4-0.5% of ischemic strokes. Clinical presentation of AOP infarction is characterized by impaired arousal and memory, language impairment and vertical gaze palsy. It also can present with cerebellar signs, hemi paresis and hemi sensory loss. We herein present a case of AOP infarction presenting as transient loss of consciousness and nuclear third nerve palsy. CASE PRESENTATION: A 51 year old previously healthy male, was brought to us, with a Glasgow coma scale (GCS) of 7/15. GCS improved to 11/15 by the next day, however he had a persisting expressive aphasia. Right sided nuclear third nerve palsy was apparent with the improvement of GCS. He did not have pyramidal or cerebellar signs. Thrombolysis was not offered as the therapeutic window was exceeded by the time of diagnosis. Diagnosis was made using magnetic resonance imaging (MRI) that was done after the initial normal non-contrast computer tomography (NCCT) brain. He was enrolled in stroke rehabilitation. Aspirin and atorvastatin was started for the secondary prevention of stroke. He achieved independency of advanced daily living by 1 month, however could not achieve full recovery to be employed as a taxi driver. CONCLUSIONS: Because of the rarity and varied clinical presentation with altered levels of consciousness, AOP infarcts are easily overlooked as a stroke leading to delayed diagnosis. Timely diagnosis can prevent unnecessary investigations and the patient will be benefitted by early revascularization. As it is seldom reported, case reports remain a valuable source of improving awareness among physicians about this clinical entity.

An unusual case of dengue shock syndrome complicated by ilio-femoral deep vein thrombosis; a case report.

BACKGROUND: Dengue fever is a hemorrhagic fever caused by flaviviruses. Hemorrhagic manifestations are well known to be associated with dengue fever, though the thrombotic events are only seldom reported. Underlying pathophysiology of thrombotic events is multifactorial and the management is challenging due to associated thrombocytopenia and bleeding tendency. We report a case of dengue shock syndrome with severe thrombocytopenia complicated by ilio-femoral deep vein thrombosis. CASE PRESENTATION: A 16 year old boy presented with dengue fever. He had dengue shock syndrome after entering the critical phase on the fifth day of the illness. With the recovery from the critical phase he developed deep vein thrombosis involving right external iliac, common femoral and superficial femoral veins. There were no provocative factors other than dengue fever itself. His platelet count was 12,000/µl at the time of diagnosis with deep vein thrombosis. Anticoagulation was started with intravenous unfractionated heparin 500 IU/hour while closely being observed for bleeding complications. 1000 IU/hour dose was commenced with the recovery of the platelet count above 50,000/µl. Thrombophilia screening was negative and he was discharged on warfarin. Venous duplex done after 6 weeks showed normal lower limb venous flow and warfarin was omitted after three months. CONCLUSIONS: With dengue fever, complications like deep vein thrombosis can be easily missed given its rarity and that the major concern is on hemorrhagic complications. Management is challenging due to associated thrombocytopenia and hemorrhagic complications.

Regulatory verification on safe use of cytotoxic drugs in veterinary clinics and animal hospitals.

BACKGROUND: Veterinarians are increasingly being asked to provide chemotherapy for veterinary patients. However, chemotherapy agents have cytotoxic effects that can pose a health risk to workers from exposure. There are no published studies examining cytotoxic drug (CTD) contamination in veterinary practices in Australia. METHODS: CTD use at 13 veterinary clinics and animal hospitals across New South Wales (NSW) was verified for compliance with Work, Health and Safety (WHS) legislation on the effectiveness of exposure control measures. Surface swab sampling was performed to detect the restricted carcinogen cyclophosphamide and seven other CTD. A total of 73 surface swab samples were collected from nine locations associated with CTD delivery, storage, treatment and waste disposal at four veterinary practices, with repeat sampling at two veterinary practices. RESULTS: Compliance with WHS legislation for systematic chemical management, including procedures for safe use of carcinogens, in veterinary practices was high: 4 of the 10 key clauses in WHS chemical management were complied with at all 13 verified workplaces. Surface contamination was detected in three locations, with levels of CTD contaminants ranging from 3.54 to 89 ng per sample. DISCUSSION: Results showed that, in general, there were safe systems in place to work with CTD in the veterinary practices that were verified in NSW. Areas for improvement were mainly in administrative measures related to hazardous chemical management. Particular attention should be given to raising awareness of the intrinsic hazards of CTD, through training and hazard information provision to staff.

Prevalence, distribution and clinical correlates of myocardial fibrosis in systemic lupus erythematosus: a cardiac magnetic resonance study.

OBJECTIVES: To assess the prevalence, distribution and clinical correlates of myocardial fibrosis, as detected by cardiac magnetic resonance (CMR), in systemic lupus erythematosus (SLE). METHODS: Forty-one subjects (average age 39 ± 12 years and 80% female) with SLE underwent CMR imaging at 1.5T, using late gadolinium enhancement (LGE) to quantify the area of myocardial fibrosis in the left ventricle (LV). Subjects also underwent transthoracic echocardiography (TTE) and exercise testing. RESULTS: LGE was detected in 15/41 subjects, 11 with localized LGE (<15% LV mass) and four with extensive LGE (>15% LV mass). The commonest site of LGE was the interventricular septum, with all but one case demonstrating an intramural or inflammatory pattern. The mean age of the >15% LGE group (55 ± 15 years) was significantly higher than the <15% or absent LGE subgroups. Based on both CMR and TTE measurements, subjects with LGE > 15% demonstrated a reduced E/A ratio of 0.9 ± 0.4 relative to the <15% and absent LGE subgroups. LV end-systolic volume (ESVi), end-diastolic volume (EDVi) and maximum exercise capacity were also reduced in the >15% LGE group. CONCLUSIONS: Mid-wall myocardial fibrosis occurs frequently in SLE and is strongly associated with advancing subject age, but not with SLE duration or severity. Extensive LGE may be associated with diastolic dysfunction and impaired exercise capacity, although this may be an epiphenomenon of age. Cardiac magnetic resonance with quantitative assessment of LGE may provide a basis for cardiac risk stratification in SLE.

PK11195 inhibits mitophagy targeting the F1Fo-ATPsynthase in Bcl-2 knock-down cells.

The pharmacological agent 1-(2-Chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195) is the prototypical ligand of the 18-kDa Translocator Protein (TSPO) but at µM concentrations deactivates the oncoprotein Bcl-2 increasing the efficiency of chemotherapeutic agents and promoting the Ca2+-dependent macro-autophagy (or autophagy). In this paper, we report that PK11195, in HeLa cells, modifies the mitochondria-targeted type of autophagy--hereafter referred to as mitophagy--and the associated resizing of the mitochondrial network but does so exclusively in absence of the oncoprotein Bcl-2 (Bcl-2 Kd cells). This is consequence of a "side" targeting of the mitochondrial F1Fo-ATPsynthase enzyme, since identical outcome is mimicked by the antibiotic Oligomycin, of which PK11195 matches the effect on: i) mitochondrial membrane potential (ΔΨm), ii) ATP homeostasis and iii) Reactive Oxygen Species (ROS) generation. Taken together, these data highlight a novel TSPO-independent biological effect for PK11195 and provide evidences for a hitherto uncovered Bcl-2-dependent role of the F1Fo-ATPsynthase in mitochondrial quality control.

Subfertile female androgen receptor knockout mice exhibit defects in neuroendocrine signaling, intraovarian function, and uterine development but not uterine function.

Female androgen receptor (AR) knockout mice (AR(-/-)) generated by an in-frame Ar exon 3 deletion are subfertile, but the mechanism is not clearly defined. To distinguish between extra- and intraovarian defects, reciprocal ovarian transplants were undertaken. Ovariectomized AR(-/-) hosts with wild-type (AR(+/+)) ovary transplants displayed abnormal estrus cycles, with longer cycles (50%, P < 0.05), and 66% were infertile (P < 0.05), whereas AR(+/+) hosts with either AR(-/-) or surgical control AR(+/+) ovary transplants displayed normal estrus cycles and fertility. These data imply a neuroendocrine defect, which is further supported by increased FSH (P <0.05) and estradiol (P <0.05), and greater LH suppressibility by estradiol in AR(-/-) females at estrus (P <0.05). Additional intraovarian defects were observed by the finding that both experimental transplant groups exhibited significantly reduced pups per litter (P < 0.05) and corpora lutea numbers (P < 0.05) compared with surgical controls. All groups exhibited normal uterine and lactation functions. AR(-/-) uteri were morphologically different from AR(+/+) with an increase in horn length (P < 0.01) but a reduction in uterine diameter (P < 0.05), total uterine area (P < 0.05), endometrial area (P < 0.05), and myometrial area (P < 0.01) at diestrus, indicating a role for AR in uterine growth and development. Both experimental transplant groups displayed a significant reduction in uterine diameter (P < 0.01) compared with transplanted wild-type controls, indicating a role for both AR-mediated intraovarian and intrauterine influences on uterine physiology. In conclusion, these data provide direct evidence that extraovarian neuroendocrine, but not uterine effects, as well as local intraovarian AR-mediated actions are important in maintaining female fertility, and a disruption of AR signaling leads to altered uterine development.

The energy response of a T.P.A. Mk-II ionization chamber using GEANT4 Monte Carlo simulation.

The low energy model of the GEANT4 Monte Carlo toolkit was used to simulate the energy response of a T.P.A. Mk-II ionization chamber under a variety of different conditions. The sample position resulting in the maximum response along the axial direction of the chamber was obtained. The parameters of the simulation were chosen to account for the maximum effect of the particle backscattering and the setting of most suitable values for the production thresholds and the energy cuts in the GEANT4 Monte Carlo code. The chamber response for different compositions of detector elements was also studied. The simulated radioactive source was a glass ampoule containing 3.6 ml of the radionuclide in an aqueous solution. The energy response of the chamber at the maximum response was obtained for simulations for (60)Co, (22)Na and (59)Fe nuclides. Verification of the simulated response was obtained using experimental measurements with radioactive sources. The simulated results were in good agreement with the experimentally measured data to within 0.04-2.0%. In the energy range below 200 keV the response curve was complex due to the increase of photoelectric cross sections of the chamber materials. Effects due to backscattering occur at boundaries between chamber elements and also become significant at sites of lead shielding at photon energies above 700 keV. The chamber response for different compositions of detector elements was also studied. The response of the chamber depended highly on the energies of emitting particles, source position and materials used in electrodes and thimble wall.

Sensitization of nanostructured TiO2 by electrostatic coupling of ionic dyes to ionic absorbates.

It is shown that an ionic dye Y can be electrostatically bonded to an ionic molecule X of opposite charge anchored to a TiO2 surface via suitable ligands. Dye-sensitized solid-state photovoltaic cells of the configuration n-TiO2/X-Y/p-CuSCN were constructed with X = trihydroxybenzoic acid or mercurochrome and Y = methyl violet. Cells of this configuration were found to be more efficient and delivered higher short-circuit photocurrents and open-circuit photovoltages compared to the cells based only on methyl violet or mercurochrome. It is suggested that this technique would be a means of extending the spectral response of dye-sensitized photovoltaic devices. The formation of a wider barrier by coupling of anionic and cationic species also improves the cell performance by suppression of recombination.

A study of air particulate pollution in Colombo using a nuclear-related analytical technique.

Air particulate matter of two size fractions (coarse [2.5-10 microns] and fine [less than 2.5 microns]) were collected at an urban residential site (Colombo University ground) over a period of 12 mo during 1996 using a Gent PM10 stacked filter unit. Seventy-five sets of samples collected during this period were analyzed for 10 elements: Al, Si, K, S, Ca, Ti, Fe, Zn, Br, and Pb by energy-dispersive X-ray fluorescence, which is a multielement analysis. This is a highly sensitive technique enabling quantitative analysis of very low masses. The average concentrations of lead, sulfur, and bromine, which are generally associated with combustion products of automotive exhausts, dominate the fine fraction in this study. The minimum and maximum concentration of lead resulting in an annual average of 0.09 microgram/m3 was found to be 0.0042 and 0.441 microgram/m3 in particulate matter with less than 10 microns equivalent aerodynamic diameter. The maximum concentration determined is well below the limits set by the World Health Organization (0.5-1.0 microgram/m3). The recommended value for Pb in Sri Lanka is 0.5 microgram/m3. Al, Si, Ca, Ti, and Fe exhibited enhanced concentrations in the coarse fraction, which probably originate from disturbed soil as a result of wind and traffic.

Hypertonic saline challenge in an adult epidemiological survey.

Bronchial provocation tests using pharmacological agents such as methacholine or histamine are used in epidemiological studies to identify asthma despite recognition of limitations in specificity, positive predictive value and availability of reagents. Hypertonic saline (4.5%) bronchial challenge (HSBC), although less sensitive than pharmacological challenges, is reportedly highly specific in diagnosing current asthma. Added advantages are that reagents are cheap, stable and recognized by participants. Thus, HSBC may offer benefits over pharmacological tests in epidemiological surveys. This paper reports on the second field survey using the test, a study of 99 adults from the timber industry in Western Australia. The test is described and critically appraised as a practical epidemiological tool for assessing asthma prevalence. At a cutoff point of 20% FEV, fall, HSBC was positive in 8% of subjects, appeared specific for asthma, was safe, well-accepted and easy to use in the field.