Genomic and expression analysis of microdissected inflammatory breast cancer

Inflammatory breast cancer (IBC) is a unique clinical entity characterized by rapid onset of erythema and swelling of the breast often without an obvious breast mass. Many studies have examined and compared gene expression between IBC and non-IBC (nIBC), repeatedly finding clusters associated with receptor subtype, but no consistent gene signature associated with IBC has been validated. Here we compared microdissected IBC tumor cells to microdissected nIBC tumor cells matched based on estrogen and HER-2/neu receptor status. Gene expression analysis and comparative genomic hybridization were performed. An IBC gene set and genomic set were identified using a training set and validated on the remaining data. The IBC gene set was further tested using data from IBC consortium samples and publicly available data. Receptor driven clusters were identified in IBC; however, no IBC-specific gene signature was identified. Fifteen genes were correlated between increased genomic copy number and gene overexpression data. An expression-guided gene set upregulated in the IBC training set clustered the validation set into two clusters independent of receptor subtype but segregated only 75 % of samples in each group into IBC or nIBC. In a larger consortium cohort and in published data, the gene set failed to optimally enrich for IBC samples. However, this gene set had a high negative predictive value for excluding the diagnosis of IBC in publicly available data (100 %). An IBC enriched genomic data set accurately identified 10/16 cases in the validation data set. Even with microdissection, no IBC-specific gene signature distinguishes IBC from nIBC. Using microdissected data, a validated gene set was identified that is associated with IBC tumor cells. Inflammatory breast cancer comparative genomic hybridization data are presented, but a validated genomic data set that identifies IBC is not demonstrated.     

The potential protective role of alpha-lipoic acid against acetaminophen-induced hepatic and renal damage

The potential protective role of alpha-lipoic acid (alpha-LA) in acetaminophen (APAP)-induced hepatotoxicity and nephrotoxicity was investigated in rats. Pretreatment of rats with alpha-LA (100mg/kg) orally protected markedly against hepatotoxicity and nephrotoxicity induced by an acute oral toxic dose of APAP (2.5 g/kg) as assessed by biochemical measurements and by histopathological examination. None of alpha-LA pretreated animals died by the acute toxic dose of APAP. Concomitantly, APAP-induced profound elevation of nitric oxide (NO) production and oxidative stress, as evidenced by increasing of lipid peroxidation level, reducing of glutathione peroxidase (GSH-Px) activity and depleting of intracellular reduced glutathione (GSH) level in liver and kidney, were suppressed by pretreatment with alpha-LA. Similarly, daily treatment of rats with a smaller dose of alpha-LA (25mg/kg) concurrently with a smaller toxic dose of APAP (750 mg/kg) for 1 week protected against APAP-induced hepatotoxicity and nephrotoxicity. This treatment also completely prevented APAP-induced mortality and markedly inhibited APAP-induced NO overproduction and oxidative stress in hepatic and renal tissues. These results provide evidence that inhibition of NO overproduction and maintenance of intracellular antioxidant status may play a pivotal role in the protective effects of alpha-LA against APAP-induced hepatic and renal damage.     

Attenuation of morphine tolerance and dependence by aminoguanidine in mice

The effect of aminoguanidine, an inducible nitric oxide synthase (iNOS) inhibitor, on morphine-induced tolerance and dependence in mice was investigated in this study. Acute administration of aminoguanidine (20 mg/kg, p.o.) did not affect the antinociceptive effect of morphine (10 mg/kg, s.c.) as measured by the hot plate test. Repeated administration of aminoguanidine along with morphine attenuated the development of tolerance to the antinociceptive effect of morphine. Also, the development of morphine dependence as assessed by naloxone-precipitated withdrawal manifestations was reduced by co-administration of aminoguanidine. The effect of aminoguanidine on naloxone-precipitated withdrawal was enhanced by concurrent administration of the non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, dizocilpine (0.25 mg/kg, i.p.) or the non-specific nitric oxide synthase (NOS) inhibitor, l-N(G)-nitroarginine methyl ester (l-NAME; 5 mg/kg, i.p.) and antagonized by concurrent administration of the nitric oxide (NO) precursor, l-arginine (50 mg/kg, p.o.). Concomitantly, the progressive increase in NO production, but not in brain glutamate level, induced by morphine was inhibited by repeated administration of aminoguanidine along with morphine. Similarly, co-administration of aminoguanidine inhibited naloxone-induced NO overproduction, but it did not inhibit naloxone-induced elevation of brain glutamate level in morphine-dependent mice. The effect of aminoguanidine on naloxone-induced NO overproduction was potentiated by concurrent administration of dizocilpine or l-NAME and antagonized by concurrent administration of l-arginine. These results provide evidence that blockade of NO overproduction, the consequence of NMDA receptor activation, by aminoguanidine, via inhibition of iNOS, can attenuate the development of morphine tolerance and dependence.     

Serotype distribution and drug resistance in Streptococcus pneumoniae, Palestinian Territories

To determine antimicrobial drug resistance of Streptococcus pneumoniae serotypes, we analyzed isolates from blood cultures of sick children residing in the West Bank before initiation of pneumococcal vaccination. Of 120 serotypes isolated, 50.8%, 73.3%, and 80.8% of the bacteremia cases could have been prevented by pneumococcal conjugate vaccines. Serotype 14 was the most drug-resistant serotype isolated.     

Investigating the job satisfaction of healthcare providers at primary healthcare centres in Lebanon: A national cross‐sectional study

Low job satisfaction is linked to higher staff turnover and intensified shortages in healthcare providers (HCP). This study investigates the level of, and factors associated with, HCP job satisfaction in the national primary healthcare (PHC) network in Lebanon. The study adopts a cross‐sectional design to survey HCP at 99 PHC centres distributed across the country between October 2013 and May 2014. The study questionnaire consisted of four sections: socio‐demographics/professional background, employment characteristics, level of job satisfaction (Measure of Job Satisfaction scale) and level of professional burnout (Maslach Burnout Inventory‐HSS scale). A total of 1,000 providers completed the questionnaire (75.8% response rate). Bivariate and multivariate regression analyses were used to identify factors significantly associated with job satisfaction. Findings of the study highlight an overall mean job satisfaction score of 3.59 (SD 0.54) indicating that HCP are partially satisfied. Upon further examination, HCP were least satisfied with pay, training and job prospects. Gender, age, career plans, salary, exposure to violence, and level of burnout were significantly associated with the overall level of job satisfaction which was also associated with increased likelihood to quit. Overall, the study highlights how compensation, development and protection of PHC HCP can influence their job satisfaction. Recommendations include the necessity of developing a nationally representative committee, led by the Ministry of Public Health, to examine the policies and remuneration scales within the PHC sector and suggest mechanisms to bridge the pay differential with other sectors. The effective engagement of key stakeholders with the development, organisation and evaluation of professional development programmes offered to HCP in the PHC sector remains crucial. Concerned stakeholders should assess and formulate initiatives and programmes that enrich the physical, psychological and professional well‐being of their HCP. The aforementioned suggestions are necessary to strengthen and sustain PHC HCP and support the provision of universal health coverage to the Lebanese population.     

Factors associated with the refusal of surgery and the associated impact on survival in patients with rectal cancer using the National Cancer Database

BackgroundSurgical resection is an integral component of the curative-intent treatment for most patients with non-metastatic rectal cancer. However, some patients refuse surgery for a number of reasons. Utilizing the National Cancer Database (NCDB), we investigated the sociodemographic and clinical factors associated with patients who were coded as having been offered but refused surgery, and the factors affecting overall survival (OS) in these patients.MethodsAdult patients with adenocarcinoma of the rectum (excluding T1N0M0 and M1 disease) diagnosed from 2004 to 2015 were analyzed in this retrospective cohort study. Logistic regression was performed to identify factors associated with refusal of surgery. OS of patients refusing surgery was compared using Kaplan-Meier estimate, log-rank test, propensity score matching, and proportional hazards regression.ResultsA total of 55,704 patients were identified: 54,266 received definitive surgery (97.4%) and 1,438 refused (2.6%). Of patients refusing surgery, 135 (9.4%) were stage I, 709 (49.3%) were stage II, and 594 (41.3%) were stage III. Patients were more likely to refuse surgery as the study period progressed (P<0.01). Factors associated with refusal of surgery on multivariate analysis include: age ≥70 years, Black race, non-private insurance, and tumor size greater than 2 cm (all values P≤0.01). The 5-year OS was 61.6% for the surgery cohort and 35.7% for the refusal cohort. In the propensity matched groups, median survival was 84.2 months in patients who received definitive surgery compared to 43.7 months in patients who refused surgery. As an index for comparison, patients who refused surgery but received both radiotherapy and chemotherapy had a median survival of 48.5 months. Among patients that refused surgery, those that received radiotherapy alone, chemotherapy alone, or radiotherapy and chemotherapy (compared to no treatment) experienced a survival benefit (all values P≤0.01).ConclusionsIn patients with non-metastatic adenocarcinoma of the rectum reported in the NCDB, age, race, and insurance status were associated with refusal of surgery. Refusal of surgery was more common in the later years of the study. Survival is poor in patients who refused surgical resection.     

The role of bacterial and non-bacterial toxins in the induction of changes in membrane transport: implications for diarrhea.

Bacterial toxins induce changes in membrane transport which underlie the loss of electrolyte homeostasis associated with diarrhea. Bacterial- and their secreted toxin-types which have been linked with diarrhea include: (a) Vibrio cholerae (cholera toxin, E1 Tor hemolysin and accessory cholera enterotoxin); (b) Escherichia coli (heat stable enterotoxin, heat-labile enterotoxin and colicins); (c) Shigella dysenteriae (shiga-toxin); (d) Clostridium perfringens (C. perfringens enterotoxin, alpha-toxin, beta-toxin and theta-toxin); (e) Clostridium difficile (toxins A and B); (f) Staphylococcus aureus (alpha-haemolysin); (g) Bacillus cereus (cytotoxin K and haemolysin BL); and (h) Aeromonas hydrophila (aerolysin, heat labile cytotoxins and heat stable cytotoxins). The mechanisms of toxin-induced diarrhea include: (a) direct effects on ion transport in intestinal epithelial cells, i.e. direct toxin interaction with intrinsic ion channels in the membrane and (b) indirect interaction with ion transport in intestinal epithelial cells mediated by toxin binding to a membrane receptor. These effects consequently cause the release of second messengers, e.g. the release of adenosine 3',5'-cyclic monophosphate/guanosine 3',5'-monophosphate, IP(3), Ca2+ and/or changes in second messengers that are the result of toxin-formed Ca2+ and K+ permeable channels, which increase Ca2+ flux and augment changes in Ca2+ homeostasis and cause depolarisation of the membrane potential. Consequently, many voltage-dependent ion transport systems, e.g. voltage-dependent Ca2+ influx, are affected. The toxin-formed ion channels may act as a pathway for loss of fluid and electrolytes. Although most of the diarrhea-causing toxins have been reported to act via cation and anion channel formation, the properties of these channels have not been well studied, and the available biophysical properties that are needed for the characterization of these channels are inadequate.     

Western Database of Lipid Variants (WDLV): A Catalogue of Genetic Variants in Monogenic Dyslipidemias

Background

Next-generation sequencing (NGS) is nearing routine clinical application, especially for diagnosis of rare monogenic cardiovascular diseases. But NGS uncovers so much variation in an individual genome that filtering steps are required to streamline data management. The first step is to determine whether a potential disease-causing variant has been observed previously in affected patients.

Methods

To facilitate this step for lipid disorders, we developed the Western Database of Lipid Variants (WDLV) of 2776 variants in 24 genes that cause monogenic dyslipoproteinemias, including conditions characterized primarily by either high or low low-density lipoprotein cholesterol, high or low high-density lipoprotein cholesterol, high triglyceride, and some miscellaneous disorders. We incorporated quality-control steps to maximize the likelihood that a listed mutation was disease causing.

Results

The details of each mutation found in a dyslipidemia, together with a mutation map of the causative genes, are shown in graphical display items.

Conclusions

WDLV will help clinicians and researchers determine the potential pathogenicity of mutations discovered by DNA sequencing of patients or research participants with lipid disorders.