Hepatic Infarction in a Patient With Sickle Cell Trait Presenting With HELLP Syndrome.

Hepatic infarction is uncommon due to the dual blood supply from the hepatic artery and portal vein. The majority of the cases are caused following liver transplant or hepatobiliary surgery, hepatic artery occlusion, or shock. Hepatic infarction is a rare complication of hemolysis, elevated liver enzymes, and low platelet (HELLP) syndrome. HELLP is an obstetrical emergency requiring prompt delivery. The presence of elevated liver enzymes, mainly alanine aminotransferase and aspartate aminotransferase in pre-eclampsia, should warrant diagnosis and treatment in the line of HELLP syndrome. Our patient with underlying sickle cell trait presented with features of HELLP syndrome in her third trimester of pregnancy. She underwent cesarean delivery on the same day of the presentation. The liver enzymes continued to rise following delivery and peaked on postoperative day two. Contrast computed tomography scan showed multifocal hepatic infarctions. Pre-eclampsia by itself is a state of impaired oxygenation and can lead to hepatic hypoperfusion, and appeared to be a clear contributor to the hepatic infarction in this case. However, this case also raises the question of whether the underlying sickle cell trait might have potentiated the hepatic infarction. Although sickle cell disease is well known to cause hepatic infarctions, it is unknown whether the sickle cell trait affects the liver to a similar extent as sickle cell disease. In addition, there have been case reports of sickle cell trait causing splenic infarcts and renal papillary necrosis, but it remains unclear if it can be directly associated with hepatic infarction.

Rapidly Progressive Granulomatous Amoebic Encephalitis in a Diabetic Individual.

We present a case of rapidly progressive granulomatous amoebic encephalitis caused by Balamuthia mandrillaris in an individual with diabetes mellitus. Our patient presented with occipital headache, blurry vision, confusion, and gait imbalance of one week's duration. Brain imaging revealed numerous peripheral ring-enhancing lesions concerning malignancy. Brain biopsy was consistent with Balamuthia mandrillaris infection. He passed away 45 days after presentation despite being treated with a five-drug regimen. This case highlights the importance of considering amoebic brain infections, especially with ring-enhancing lesions on imaging. There are opportunities to design modalities for rapid diagnosis and better treatment.

A Laplacian-Gaussian Mixture Model for Surface EMG Signals from Upper Limbs.

Existing literature suggests that the probability density function (pdf) of surface Electromyography (sEMG) signals follows either a Gaussian or Laplacian model. In this paper, a Laplacian-Gaussian mixture model is proposed for the EMG signals extracted from the upper limbs. The model is validated using both quantitative and qualitative perspectives. Specifically, for a benchmark dataset, the Kullback-Leibler (KL) divergence is computed between the proposed model and the histogram based empirical probability density function (mpdf). For a sample signal, a goodness of fit plot with R squared value and a visual comparison between the histogram based mpdf and the estimated pdf from the proposed model are presented. Moreover, the Expectation-Maximization (EM) algorithm is derived for the estimation of the parameters of the proposed mixture model. The weight of the Laplacian component is computed for each of the signals from a benchmark dataset. It has been empirically determined that the Laplacian component has a major contribution to the mixture.

Pharmacotherapies in Heart Failure With Preserved Ejection Fraction: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Heart failure (HF) with preserved ejection fraction (HFpEF) causes significant cardiovascular morbidity and mortality. It is a growing problem in the developed world, especially, in the aging population. There is a paucity of data on the treatment of patients with HFpEF. We aimed to identify pharmacotherapies that improve peak oxygen consumption (peak VO2), cardiovascular mortality, and HF hospitalizations in patients with HFpEF. METHODS: We conducted a systematic literature search for English studies in PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Google scholar. We searched databases using terms relating to or describing HFpEF, stage C HFpEF, and diastolic HF and included only randomized controlled trials (RCTs). RevMan 5.4 (The Cochrane Collaboration, 2020, London, UK) was used for data analysis, and two independent investigators performed literature retrieval and data-extraction. We used PRISMA guidelines to report the outcomes. We included 14 articles in our systematic review and six studies in meta-analysis. RESULTS: We calculated the pooled mean difference (MD) of peak VO2 between placebo and pharmacotherapies. Our meta-analysis showed that the peak VO2 was comparable between pharmacotherapies and placebo in HFpEF (MD = 0.09, 95% CI: -0.11, 0.30, I2 =28%). Our systematic review highlights that statins and spironolactone use should be further studied in larger RCTs due to their potential beneficial effect on all-cause mortality and hospitalizations, respectively. CONCLUSION: Compared to placebo, none of the pharmacotherapies significantly improved peak VO2 in HFpEF except ivabradine. In our meta-analysis, the pooled improvement in peak VO2 is non-significant. This needs validation with larger studies. We are lacking larger studies on pharmacotherapies that improve peak VO2 in HFpEF. Statin and spironolactone should be further studied in patients with HFpEF as few trials have shown improvement in all-cause mortality and reduction in HF hospitalizations in selected patients, respectively.

Formulation of PEG-ylated L-asparaginase loaded poly (lactide-co-glycolide) nanoparticles: influence of Pegylation on enzyme loading, activity and in vitro release.

The present paper describes the advantage of PEG-ylation of L-asparaginase before encapsulation over its incorporation in the native form. During encapsulation a considerable amount of native protein undergoes denaturation and forms insoluble aggregates. In an effort to overcome this problem, L-asparaginase was PEG-ylated before subjecting it to the harsh conditions as encountered during double emulsion solvent evaporation technique. L-asparaginase was conjugated with succinimidyl succinate derivative of polyethylene glycol (SS-PEG, MW 5000) followed by characterization of the formed conjugate using size exclusion-HPLC and SDS PAGE. The PEG-ylated L-asparaginase consisted of different isomers from mono to multi PEG-ylated depending upon the number of Lysine residues (14 in case of L-asparaginase) with about 5% as native protein. The specific activity as retained after PEG-ylation was 62.84 +/- 8.2% and further about 82.7% of activity was recovered from the particles. Imitated studies with the native protein confirmed the enhanced stability of the conjugated protein when exposed to the organic solvent and sonication and showed comparatively less encapsulation efficiency due to increased hydrophilicity. Release profiles for native as well as conjugated proteins consisted of sustained release of about 66.66% and 44.45% in 28 days, respectively. The decrease in the release can be attributed to the increase in the molecular weight of the conjugated protein. The study finally proved that PEG-ylation protected the enzyme and prevented it from denaturation during encapsulation.

Controlled release of bioactive recombinant human growth hormone from PLGA microparticles.

Controlled release formulation of recombinant human growth hormone (r-hGH) was achieved using poly lactide-co-glycolide (PLGA) polymer. Denaturation of r-hGH by dichloromethane during primary emulsification step of particle preparation was minimized by using human serum albumin whereas inclusion of sucrose and sodium bicarbonate helped in reducing protein denaturation during lyophilization and polymer particle degradation. Encapsulation efficiency of r-hGH entrapped in PLGA particles (size approximately 30 microm) was around 45% with protein load 20 microg of r-hGH/mg of polymer particles. Porous particles showed quick release of r-hGH in comparison to non-porous particles in vitro. More than 10 ng/mL of bioactive r-hGH was found in the serum of the experimental animals observed for a 30-day period after a single intramuscular injection of the polymeric formulation. Incorporation of optimal stabilizers is thus essential for the development of a stable, month long controlled release of polymer particle based r-hGH formulation.

Effect of Metoprolol CR/XL on pulmonary artery pressure in chronic heart failure patients assessed by an implanted ultrasonic device with special emphasis on diurnal variation and exercise capacity.

OBJECTIVE: We evaluated the impact of Metoprolol CR/XL on the diurnal and exercise induced variation on Pulmonary Artery Pressure (PAP) in patients with Chronic Heart Failure (CHF) by implanted ultrasonic device. BACKGROUND: Metoprolol produces haemodynamic and clinical benefits in patients with chronic heart failure and improves survival rate. There is limited information about their effect on PAP, its diurnal and exercise induced variation in heart failure. This study evaluates the diurnal variation and effects of exercise capacity on PAP and impact of Metoprolol CR/XL (XL) on these variations on PAP in CHF patients. METHODS: In this first-in-man study, ten NYHA class III/IV patients were implanted with an ultrasonic pressure-monitoring device, followed a month later by loading with MXL 25 mg/day and uptitrated every two weeks to 200 mg/day. PAP was measured at each follow up. Diurnal variation was evaluated at baseline (no MXL), 100, and 200 mg/day MXL. Treadmill Test (TMT) was performed before and at each uptitration. Echocardiography was performed at one year. RESULTS: Uptitrating MXL caused a slight initial rise in PAP, followed by a subsequent decrease on reaching 200 mg/day dose. One patient showed repeated symptomatic rise in PAP indicating MXL intolerance and was discontinued from the uptitration. The nocturnal rise in PAP at baseline was reduced on reaching 200 mg/day MXL dose. Uptitrating MXL to 200mg7divide;day improved exercise time and metabolic equivalent tasks (METS) with no significant change in post TMT PAP. Ejection fraction also improved at one-year follow-up. CONCLUSIONS: PAP increases post exercise and diurnally in CHF patients. Slow and careful uptitration of MXL with simultaneous non-invasive monitoring of PAP may benefit in nocturnal rise and exercise capacity in CHF patients.

Safety of Angiotensin-converting enzyme inhibitors in patients with insect venom allergies.

OBJECTIVE: To review the literature with respect to the safety of angiotensin-converting enzyme (ACE) inhibitors in patients allergic to insect venom and those undergoing venom immunotherapy (VIT). DATA SOURCES: A MEDLINE search was conducted (1966-March 2006) using the following search terms: bee sting, venom, insect stings, ACE inhibitors, angiotensin II receptor blockers, immunotherapy, and desensitization. The bibliographies of qualifying articles were also searched for relevant references. DATA SYNTHESIS: Several case reports have described severe allergic reactions, including anaphylaxis, in patients taking ACE inhibitors subsequent to being stung or receiving VIT. Exacerbation of the allergic response by ACE inhibitors is thought to be related to accumulation of bradykinin and inhibition of the formation of angiotensin II. Similar reactions have not been described with angiotensin-receptor blockers, but are theoretically possible. CONCLUSIONS: ACE inhibitors may exacerbate the response to insect venom, resulting in potentially life-threatening allergic reactions to insect stings or VIT. Although this risk is difficult to quantify based only on data from case reports, it seems prudent that patients with documented allergic reactions to insect venom avoid ACE inhibitor therapy, if possible. If, after careful consideration of the risks and benefits, ACE inhibitor therapy is deemed warranted, education regarding measures to minimize exposure to insect stings and training on self-administration of epinephrine should be provided, as with any person with venom allergy. In patients in whom VIT is appropriate, temporary discontinuation of the ACE inhibitor prior to each venom injection may prevent subsequent adverse reactions.