N-myristoyltransferase: A potential novel diagnostic marker for colon cancer

Background  

Colon cancer is the second leading cause of cancer deaths in the western world. If detected early, colorectal cancer is one of the most treatable forms of cancer. Unfortunately, very few people are screened. N-myristoyltransferase (NMT) catalyzes myristoylation of various proteins including oncoproteins. We have demonstrated earlier the alteration of NMT activity during the progression of colorectal cancer and established NMT as a putative therapeutic target for cancer.     

Resolution of Postural Orthostatic Tachycardia Syndrome After CT-Guided,Percutaneous T2 Ethanol Ablation for Hyperhidrosis

Postural orthostatic tachycardia syndrome is characterized by orthostatic intolerance. Orthostasis (or other mild physical stress) triggers a cascade of inappropriate tachycardia, lightheadedness, palpitations, and often fainting. The underlying defect is sympathetic dysregulation of the heart, which receives its sympathetic tone from the cervical and upper thoracic sympathetic ganglia. Primary hyperhidrosis is also thought to be the result of sympathetic dysregulation. We present the case of a patient treated with CT-guided, percutaneous T2 EtOH sympatholysis for craniofacial hyperhidrosis. The patient also suffered from postural orthostatic tachycardia syndrome for many years and was unresponsive to treatment. Immediately after sympatholysis, the patient experienced resolution of both craniofacial hyperhidrosis and postural orthostatic tachycardia syndrome.     

Antihypertensive therapy versus alternative therapeutic options for prehypertension: an evidence-based approach

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-7) defines hypertension as systolic blood pressure (BP) ≥140 mmHg or diastolic BP ≥90 mmHg. The JNC-7 defines 'prehypertension' to include systolic BP values between 120 and 139 mmHg and diastolic BP values between 80 and 89 mmHg. Individuals with blood pressure in the prehypertension range are clearly at increased risk of developing hypertension in the future and have an increased risk of cardiovascular morbidity and mortality, compared with those with normal BP. However, there is paucity of evidence to intervene in these patients. In this article we discuss an evidence-based approach to therapeutic options in patients with prehypertension.     

CRF22_01A1 is involved in the emergence of new HIV-1 recombinants in Cameroon

Cameroon is a West African country where high genetic diversity of HIV-1 has been reported. The predominant CRF02_AG is involved in the emergence of more complex intersubtype recombinants. In this study, we sequenced the full-length genome of a novel unique recombinant form of HIV-1, 02CAMLT04 isolated in blood donors in urban Cameroon. Phylogenetic tree and bootscan analysis showed that 02CAMLT04 was complex and seemed to be a secondary recombinant derived from CRF02_AG and CRF22_01A1. The genomic composition of 02CAMLT04 strain showed that it is composed of 3 segments; 24% of the genome is classified as CRF02_AG, spanning most of the envelope gene. The remaining 76% of the genome is classified as CRF22_01A1. In addition, the sequence analysis of 13 full-length sequences from HIV-1-positive specimens received from Cameroon between 2002 and 2010 indicated that 5 specimens are pure CRF22_01A1 viruses, and 6 others have homology with CRF22_01A1 sequences in either gag, pol, or env region, whereas 6% of strains contain portions of CRF22_01A1. Further study demonstrated that CRF22_01A1 is a primary prevalence strain co-circulating in Cameroon and is involved in complex intersubtype recombination events with subtypes (D or F), subsubtypes (A1 or F2), and CRFs (CRF01_AE or CRF02_AG). Our studies show that novel recombinants between CRF22_01A1 and other clades and recombinant forms may be emerging in Cameroon that could contribute to the future global diversity of HIV-1 in this region and worldwide.     

Financial impact of ivabradine on reducing heart failure penalties under the Hospital Readmission Reduction Program

Objective: The introduction of the Hospital Readmission Reduction Program (HRRP) has led to renewed interest in developing strategies to reduce 30?day readmissions among patients with heart failure (HF). In this study, a model was developed to investigate whether the addition of ivabradine to a standard-of-care (SoC) treatment regimen for patients with HF would reduce HRRP penalties incurred by a hypothetical hospital with excess 30?day readmissions.

Research design: A model using a Monte Carlo simulation framework was developed. Model inputs included national hospital characteristics, hospital-specific characteristics, and the ivabradine treatment effect as quantified by a post hoc analysis of the Systolic Heart failure treatment with the I_f inhibitor ivabradine Trial (SHIFT).

Results: The model computed an 83% reduction in HF readmission penalty payments in a hypothetical hospital with a readmission rate of 22.95% (excess readmission ratio = 1.056 over the national average readmission rate of 21.73%), translating into net savings of $44,016. A sensitivity analysis indicated that the readmission penalty is affected by the specific characteristics of the hospital, including the readmission rate, size of the ivabradine-eligible population, and ivabradine utilization.

Conclusions: The results of this study indicate that the addition of ivabradine to an SoC treatment regimen for patients with HF may lead to a reduction in the penalties incurred by hospitals under the HRRP. This highlights the role ivabradine can play as part of a wider effort to optimize the care of patients with HF.     

Overexpression of Akt/PKB modulates N‐myristoyltransferase activity in cancer cells

N‐myristoyltransferase (NMT) catalyses the myristoylation reaction. Since NMT activity is elevated in various cancers and activated Akt/PKB leads to cell survival, we were interested in studying if activation of Akt/PKB has any effect on NMT. Overexpression of constitutively active Akt/PKB in HepG2 cells (HepG2‐CA‐Akt/PKB) led to an approximately 50% reduction of NMT compared with parental HepG2 cells. Reduced NMT activity in HepG2‐CA‐Akt/PKB was found to be due to the NMT1 phosphorylation. We determined NMT activity in various human breast cancer cell lines with differing metastatic potentials and pseudo‐normal breast cells (HBL‐100). Tumourigenic or metastatic breast cancer cell lines such as MDA‐MB‐231, MDA‐MB‐435, and Hs 578T displayed reduced NMT activity. Western blot analysis revealed that NMT1 is phosphorylated in these breast cancer cells. Furthermore, patients' breast cancer tissue array revealed strong positivity and high intensity for NMT in malignant breast tissues compared with normal breast cells. A gradation in the NMT staining was observed for grade I, II, and III infiltrating ductal carcinoma breast tissues. These studies demonstrate that overexpression of Akt/PKB results in NMT1 phosphorylation and that NMT1 is phosphorylated in breast cancer cells. Immunohistochemical analysis suggests that NMT may prove to be an added diagnostic biomarker for breast cancer. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.