Simultaneous spectrophotometric determination of Co (II) and Co (III) in acidic medium with partial least squares regression and artificial neural networks.

This study aims at the application of two chemometric techniques to visible spectra of acetic acid solutions of Co (II) and Co (III) for simultaneous determination thereof. Spectral data of 145 samples in the range of 400-700 nm were used to build the models. Partial least squares regression models were developed for which latent variables were determined using internal cross-validation with a leave-one-out strategy and 3 and 2 latent variables were selected for Co(II) and Co(III) based on root mean square error of cross-validation. For these models, root mean square errors of prediction were 1.16 and 0.536 mM and coefficients of determination were 0.975 and 0.892 for Co (II) and Co (III). As an alternate method, artificial neural networks consisting of three layers, with 10 neurons in hidden layer, were trained to model spectra and concentrations of cobalt species. Levenberg-Marquardt algorithm with feed-forward back-propagation learning resulted root mean square errors of prediction of 0.316 and 0.346 mM for Co (II) and Co (III) respectively and coefficients of determination were 0.996 and 0.988.

A multi-disciplinary approach to the management of intra-venous and intra-cardiac leiomymatosis: A case report.

We herein report a rare presentation of leiomyoma in a 46-year-old female who presented with complaints of shortness of breath on exertion associated with palpitations for the past one year with a history of irregular menstrual bleeding. Ultrasonography of the abdomen and pelvis revealed an enlarged, distorted uterus with multiple intramural fibroids. A trans-thoracic echocardiography was then performed which showed a large right atrial mass. To investigate further, a contrast enhanced computed tomography was performed covering entire chest and upper abdomen. It showed a large lesion in the right atrium of the heart measuring 6x5cm. The lesion appeared hypo dense and was abutting the tricuspid valve and posterior wall of the Right Atrium. It revealed the Right Atrial lesion extending into the Inferior Vena Cava and lower down into the Common Iliac Confluence, Left Common Iliac and External Iliac Veins. A multi-disciplinary approach was undertaken; the patient underwent a single stage procedure involving a total abdominal hysterectomy with bilateral Salpingo-Oophorectomy followed by excision of the intra-cardiac tumour. Recovery was uneventful and the patient was successfully discharged on the 5th post-operative day. Due to the lack of literature and low incidence of this disease, this case report presents a rare opportunity to define management guidelines for such occurrences in the future.

Feasibility assessment of yttrium-90 liver radioembolization imaging using amplitude-based gated PET/CT.

PURPOSE: The usage of PET/computed tomography (CT) to monitor hepatocellular carcinoma patients following yttrium-90 (Y) radioembolization has increased. Respiratory motion causes liver movement, which can be corrected using gating techniques at the expense of added noise. This work examines the use of amplitude-based gating on Y-PET/CT and its potential impact on diagnostic integrity. PATIENTS AND METHODS: Patients were imaged using PET/CT following Y radioembolization. A respiratory band was used to collect respiratory cycle data. Patient data were processed as both standard and motion-corrected images. Regions of interest were drawn and compared using three methods. Activity concentrations were calculated and converted into dose estimates using previously determined and published scaling factors. Diagnostic assessments were performed using a binary scale created from published Y-PET/CT image interpretation guidelines. RESULTS: Estimates of radiation dose were increased (P<0.05) when using amplitude-gating methods with Y PET/CT imaging. Motion-corrected images show increased noise, but the diagnostic determination of success, using the Kao criteria, did not change between static and motion-corrected data. CONCLUSION: Amplitude-gated PET/CT following Y radioembolization is feasible and may improve Y dose estimates while maintaining diagnostic assessment integrity.

90Y Liver Radioembolization Imaging Using Amplitude-Based Gated PET/CT.

The usage of PET/CT to monitor patients with hepatocellular carcinoma following Y radioembolization has increased; however, image quality is often poor because of low count efficiency and respiratory motion. Motion can be corrected using gating techniques but at the expense of additional image noise. Amplitude-based gating has been shown to improve quantification in FDG PET, but few have used this technique in Y liver imaging. The patients shown in this work indicate that amplitude-based gating can be used in Y PET/CT liver imaging to provide motion-corrected images with higher estimates of activity concentration that may improve posttherapy dosimetry.

Quantitative and qualitative comparison of continuous bed motion and traditional step and shoot PET/CT.

New developments in PET/CT technology have enabled the commercial availability of continuous bed motion (CBM) acquisition methods. This technology has some potential performance benefits compared to standard step and shoot (SS) imaging, however, this technology has not been assessed with regard to quantitative and image quality parameters compared to traditional SS techniques. This study seeks to compare clinically relevant quantitative and image quality parameters using CBM and SS data collection methods with the intent of providing assistance in making educated decisions regarding imaging protocol development when using CBM technology versus SS imaging.

Optimized liquid-liquid extractive rerefining of spent lubricants.

Central composite design methodology has been employed to model the sludge yield data obtained during liquid-liquid extractive rerefining of spent lubricants using an alcohol (1-butanol) and a ketone (methyl ethyl ketone) as prospective solvents. The study has resulted in two reasonably accurate multivariate process models that relate the sludge yield (R (2) = 0.9065 and 0.9072 for alcohol and ketone, resp.) to process variables (settling time t, operating temperature T, and oil to solvent ratio r). Construction of such models has allowed the maximization of the sludge yield (more than 8% and 3% in case of alcohol and ketone, resp.) so that the extraction of useable oil components from spent lubricants can economically be performed under extremely mild conditions (t = 16.7 h, T = 10°C, and r = 2) and fairly moderate conditions (t = 26.6 h, T = 10°C, and r = 5) established for the alcohol and ketone correspondingly. Based on these performance parameters alcohol appears to be superior over ketone for this extraction process. Additionally extractive treatment results in oil stocks with lesser quantity of environmentally hazardous polyaromatic hydrocarbons that are largely left in the separated sludge.

Present status and upcoming prospects of hedgehog pathway inhibitors in small cell lung cancer therapy.

Lung cancer is an important etiology of malignant mortality worldwide with global statistics indicating over 1 million deaths annually. Although there have been advances in cytotoxic chemotherapy, the prognosis after treatment still remains poor. Remarkably, recent studies on the molecular level are creating the possibility to hamper lung cancer by inhibiting the hedgehog pathway. Currently, hedgehog pathway inhibitors include IWP-2, cyclopamine and aprotinin. However, Vismodegib is a new upcoming prospect which has shown positive results while undergoing clinical trials. If approved, it may lead to a novel class of anti-cancer therapy for patients seeking treatment for small cell lung cancer.

Risk factors associated with birth defects at a tertiary care center in Pakistan.

BACKGROUND: Birth defects are defined as those conditions that are substantially determined before or during birth and which are recognizable in early life. They are an important cause of morbidity and mortality in infants. The main objective of the study was to determine the association of certain risk factors with birth defects occurring in pediatric patients seeking care in Civil Hospital, Karachi. METHODS: This was a prospective, cross-sectional study conducted at Department of Pediatrics: Units I, II and III of Civil Hospital Karachi, which is a tertiary care hospital located in the city center. These units provide care to pediatric patients from all over the country, with majority belonging to a low socioeconomic background. All infants with at least one birth defect were approached and their mothers interviewed. Demographics of both the mother and the infant were noted. Questions regarding possible exposure to risk factors were asked. Infants who were not accompanied by their mothers were excluded from the study. RESULTS: A total of 587 out of 669 infants completed the study successfully. Of these, defects related to urogenital system (19.9%) were the commonest, followed by those related to eye (16.9%), musculoskeletal system (12.9%), body wall defects (12.3%), oral cavity (12.1%), central nervous system (10.9%), gastrointestinal tract (3.2%), cardiovascular system (2.7%) and those related to ear, nose and throat (1.2%). CONCLUSION: 669(4.1%) out of a total of 16,394 pediatric patients visiting the hospital during our study were identified as having at least one birth defect. The commonest ones were those related to the eye and the urogenital system. The main factors that influence the occurrence can be grouped into maternal, socioeconomic, nutritional and educational.

Carotid artery stenting in high risk patients--results of first twelve patients at Shifa International Hospital, Islamabad, Pakistan.

OBJECTIVE: Carotid artery stenting (CAS) is emerging as an alternative procedure to carotid endarterectomy. It is mostly performed in patients with high surgical risk. Many centers in Pakistan have started CAS. We present results of 1st twelve patients who underwent carotid artery stenting at Shifa International Hospital, Islamabad. METHODS: Our carotid intervention team is comprised of a vascular neurologist, interventional cardiologist and interventional radiologist. Based on high risk criteria/patient choice, patients are recruited for CAS. Carotid artery stenting using standard technique with embolic protection device is performed. RESULTS: Twelve carotid artery stenting procedures were done between August 2006 and March 2008. One patient had TIA before stent deployment and was excluded from final analysis. Of the other 11 patients, ten were males, with mean age of 68.2 +/- 11.3 years (median age 71). Ten were symptomatic; one asymptomatic with complete occlusion of contralateral internal carotid artery. High-risk criteria were present in all: complete contralateral occlusion (2 patients); age greater than 70 years (7 patients); severe coronary artery disease (7 patients) and previous ipsilateral endarterectomy (1 patient). The stenosis ranged between 60-95%. Embolic protection device was used in nine (82%). Five (46%) patients developed hypotension requiring intravenous vasopressors. One of them developed persistent hypotension despite maximum pressor support and died. None developed neurological deterioration, acute renal failure, or haematomas/ pseudoaneurysm formation. One-year follow-up is available on two patients with patent stent and no neurological events. CONCLUSION: Hypotension is a common and potentially lethal complication of carotid artery stenting. Our results suggest that a multidisciplinary team approach with availability of specialized care can provide results comparable to internationally acceptable outcomes.

Clinical outcomes of sirolimus with eluting stent implantation in coronary artery disease.

OBJECTIVE: To evaluate the immediate post procedure, thirty-days, and six-months clinical outcomes of sirolimus-eluting stents (SES) implantation in patients with single and multivessel coronary artery disease (CAD). METHODS: A case series of all consecutive patients undergoing percutaneous coronary interventions (PCI) with SES implantation at Shifa International Hospital, Islamabad, were evaluated at early post-procedure, 30-days and six-months clinical follow-up for the incidence of major adverse cardiac event (MACE). This included death, nonfatal myocardial infarction (MI) and repeat revascularization. RESULTS: Out of 206 consecutive patients, 324 had SES implanted. Cumulative MACE rate was 2.93% and 6% at 30-days and six-months follow-ups respectively. Five patients developed ST-segment elevation MI (STEMI). One patient developed non-STEMI. Emergency Coronary Artery Bypass Grafting (CABG) was done in two patients. Repeat (PCI) was carried in three (1.46%) patients for acute in-stent thrombosis. Diabetes Mellitus and multivessel stenting were found to be the independent predictors for acute in-stent thrombosis (P-value < 0.02 and 0.05 respectively). CONCLUSION: SES implantation in coronary artery disease can be safe and effective MACE at one and six months follow-ups.

Enhancement of antitumor effect of paclitaxel in combination with immunomodulatory Withania somnifera on benzo(a)pyrene induced experimental lung cancer.

The current experimental work deals with the immunomodulatory studies on the extract of Withania somnifera (L.) Dunal root powder against benzo(a)pyrene induced lung cancer in male Swiss albino mice. In our previous study, we reported the antioxidant and anticarcinogenic effect of W. somnifera (L.) Dunal along with paclitaxel. Immune dysfunction has been found to be associated with cancer and chemotherapy. Benzo(a)pyrene induced cancer animals were treated with 400mg/kg bodyweight of W. somnifera (L.) Dunal extract for 30 days significantly alters the levels of immunocompetent cells, immune complexes and immunoglobulins. Based on the data, the carcinogen as well as the paclitaxel affects the immune system, the toxic side effects on the immune system is more reversible and more controllable by W. somnifera (L.) Dunal. These results concluded the immunomodulatory activity of W. somnifera (L.) Dunal extract, which is a known immunomodulator in indigenous medicine.

Diagnostic and therapeutic implications of ST-segment elevation in lead aVR of 12 lead ECG during chest pain.

'aVR' is usually not the preferred lead to diagnose myocardial infarction in clinical settings, it is rather a neglected lead in this context. We describe the case of a 44 year old male who presented with short duration chest pain and ST segment elevation in lead 'aVR'. His left heart catheterization showed left main stem equivalent disease and totally occluded right coronary artery. Patient underwent emergency coronary artery bypass-grafting with favorable outcome. This case highlights the significance of ST segment elevation in lead aVR during chest pain both in diagnosis and management of patients with acute coronary syndrome.

Apigenin inhibits oxidative stress-induced macromolecular damage in N-nitrosodiethylamine (NDEA)-induced hepatocellular carcinogenesis in Wistar albino rats.

Apigenin (4',5,7-trihydroxyflavone), a flavone subclass of flavonoid widely distributed in many herbs, fruits, and vegetables is a substantial component of the human diet and has been shown to possess a variety of biological activities including tumor growth inhibition and chemoprevention. Recent studies in several biological systems have shown that apigenin induces tumor growth inhibition, cell cycle arrest, and apoptosis. Free radical-induced degradation of polyunsaturated fatty acid results in electrophilic products and causes severe oxidative stress. Oxidative stress induced by free radicals, nonoxidizing species, electrophiles, and associated DNA damages have been frequently coupled with carcinogenesis. In the present study, the protective role of apigenin was examined against the oxidative stress caused by N-nitrosodiethylamine (NDEA) and phenobarbital (PB) in Wistar albino rats. Oxidative stress was measured in terms of lipid peroxidation (LPO) and protein carbonyl formation. Oxidative stress-induced DNA damage was measured by single cell gel electrophoresis (comet assay). Apigenin exhibited its antioxidant defense against NDEA-induced oxidative stress. We have observed minimal levels of LPO and DNA damage in apigenin-treated hepatoma bearing animals. Based on the results, we suggest that apigenin may be developed as a promising chemotherapeutic agent against the development of chemical carcinogenesis.

Oral supplementation of piperine leads to altered phase II enzymes and reduced DNA damage and DNA-protein cross links in Benzo(a)pyrene induced experimental lung carcinogenesis.

In recent years, considerable emphasis has been focused on identifying new chemopreventive agents, which could be useful for the human population. Piperine is a pure, pungent alkaloid constituent of black and long peppers (piper nigrum and piper longum), which is a most common spice used throughout the world. In the present study, we examined the protective role of piperine during experimental lung carcinogenesis with reference to its effect on DNA damage and detoxification enzyme system. The activities of detoxifying enzymes such as glutathione transferase (GST), quinone reductase (QR) and UDP-glucuronosyl transferase (UDP-GT) were found to be decreased while the hydrogen peroxide level was increased in the lung cancer bearing animals. Supplementation of piperine (50 mg/kg bwt) enhanced the detoxification enzymes and reduced DNA damage as determined by single cell electrophoresis. Furthermore, the DNA-Protein cross links which was found to be high in lung cancer bearing animals was also modulated upon supplementation with piperine. Our present results explain the understanding of unique association between anti-peroxidative effect of piperine and ultimately the capability of piperine to prevent cancer.

Protective effect of piperine on benzo(a)pyrene-induced lung carcinogenesis in Swiss albino mice.

BACKGROUND: The statistics on lung cancer necessitates the urge to develop new methods to control this most deadly form of cancer. Chemoprevention is one of these new approaches. Carcinogens from cigarette smoke form the link between nicotine addiction and lung cancer. At the same time, it has become increasingly clear that dietary and genetically determined factors play an important role in modulating the individual susceptibility and are linked to the chemoprevention approach. In this study, the ability of piperine to prevent lung carcinogenesis in mice was characterized and its effects on cell proliferation and protein damage biomarkers were determined. METHODS: Thirty Swiss albino mice were divided into five groups of six animals each. Animals in group I received corn oil orally and served as control. Group II were administered with 50 mg/kg b.wt. of benzo(a)pyrene (B(a)P) twice a week for 4 consecutive weeks to induce lung cancer by the end of 16th week. Group III received 50 mg/kg b.wt. piperine on alternate days for 16 weeks immediately after the first dose of carcinogen. Group IV also received piperine as in group III but from the sixth week of B(a)P induction till the end of the experiment. Group V animals constituted the drug control and received piperine alone. RESULTS: Administration of piperine significantly decreased the levels of lipid peroxidation, protein carbonyls, nucleic acid content and polyamine synthesis that were found to be increased in lung cancer bearing animals. CONCLUSIONS: Piperine could effectively inhibit B(a)P-induced lung carcinogenesis in albino mice by offering protection from protein damage and also by suppressing cell proliferation.