Effects of some common additives on the antimicrobial activities of alcohol-based hand sanitizers

Objective: To study the effects of some common additives on the antimicrobial activities of alcohol-based hand sanitizers. Methods: The antibacterial activities of varying aqueous concentrations of ethanol and isopropyl alcohol were tested by the agar well diffusion method. The influences of different concentrations of glycerin was similarly tested. Finally, isopropyl alcohol and benzalkonium chloride were combined in different ratios within the sate use concentrations of each, and the effects of these combinations were compared with values obtained for the two agents used alone. Statistical methods, such as student t test and one-way ANOVA were used when appropriate to evaluate the differences in activity. Results: The activities of the alcohols showed marked concentration dependence, and both showed peak activity at 85%-95% concentration range. Over the concentration range of 60%-100%, isopropyl alcohol inhibited more bacterial and fungal organisms than ethanol, though the inhibition zone diameters it produced were not statistically different from those of ethanol for organisms which were sensitive to both of them.Addition of glycerin reduced the antimicrobial activities of the isopropyl alcohol, as shown by reduction in the inhibition zone diameters produced in vitro, which may be due to reduced drug diffusion with increase in viscosity. Addition of benzalkonium to isopropyl alcohol systems improved the activity of the alcohol, but the overall activity of the combination was not superior to that seen in the use of benzalkonium alone. Conclusion: Alcohol-based hand sanitizers should not be used outside the concentration range of 85%-95% and isopropyl alcohol inhibits more bacterial and fungal organisms than ethanol for most concentrations. Inclusion of benzalkonium improves the antimicrobial spectrum and activity of isopropyl alcohol, and the combination may justifiably be used to achieve both immediate and long lasting effect. Glycerin may adversely affect the antimicrobial activities of isopropyl alcohol-based hand sanitizers and should be used with caution.     

Diabetes and the risk of stroke

Diabetes is an important risk factor for the development of ischemic cerebrovascular disease or stroke. Diabetic patients are more susceptible to atherothromboembolic brain infarction and its consequent mortality than nondiabetic patients. Cerebrovascular disease in the diabetic population somewhat follows the same pattern as in the nondiabetic population, however, with greater severity in outcome for the former. The etiopathogenetic mechanisms of strokes and transient ischemic attacks in diabetic patients are apparently due to cerebral hemodynamic and vascular derangements, hyperglycemia, and other related risk factors. There is a great disparity in the wider information on coronary heart disease and stroke than on diabetes and stroke. A better understanding is required for the determinants of stroke and diabetes, and the epidemiology and pathophysiology of specific risk factors in different racial groups. There is a similarity in the evaluation, assessment, and management of diabetic and nondiabetic patients.     

Trends in the prevalence, awareness, treatment and control of hypertension: the WHO MONICA Project.

OBJECTIVE: To describe the secular changes in the prevalence, awareness, treatment and control of hypertension. DESIGN: Two independent cross-sectional population surveys using standardized methods conducted between the early 1980s and mid-1990s. SETTING: Twenty-four geographically defined populations of the WHO MONICA Project. PARTICIPANTS: Randomly selected men and women aged 35-64 years. The total number of participants was 69 907. MAIN OUTCOME MEASURES: Two definitions of hypertension were used: 160/95 mmHg or above and 140/90 mmHg or above for systolic or diastolic blood pressure. Subjects on antihypertensive drug treatment were considered to be hypertensive regardless of their blood pressure. Treated subjects whose measured blood pressure level was less than 160/95 or 140/90 mmHg according to the two definitions, respectively, were considered to be adequately treated. RESULTS: The age-adjusted prevalence of hypertension decreased in most and increased in only a few populations. For both definitions of hypertension, the proportion of hypertensive subjects who were aware of their condition increased in three-quarters of the male populations and in two-thirds of the female populations. Furthermore, the proportion of hypertensive individuals on antihypertensive drug treatment increased in three-quarters of the populations. In the final survey, hypertension tended to be better treated and controlled in women than in men. Nevertheless, a large proportion of patients receiving antihypertensive drug therapy still had inadequately controlled blood pressure levels. CONCLUSION: Although awareness and treatment of hypertension according to the data obtained during the late 1980s to the mid-1990s increased in several populations, the effectiveness of antihypertensive treatment showed the continuing need for improvements.     

Toxin Kid uncouples DNA replication and cell division to enforce retention of plasmid R1 in Escherichia coli cells

Worldwide dissemination of antibiotic resistance in bacteria is facilitated by plasmids that encode postsegregational killing (PSK) systems. These produce a stable toxin (T) and a labile antitoxin (A) conditioning cell survival to plasmid maintenance, because only this ensures neutralization of toxicity. Shortage of antibiotic alternatives and the link of TA pairs to PSK have stimulated the opinion that premature toxin activation could be used to kill these recalcitrant organisms in the clinic. However, validation of TA pairs as therapeutic targets requires unambiguous understanding of their mode of action, consequences for cell viability, and function in plasmids. Conflicting with widespread notions concerning these issues, we had proposed that the TA pair kis-kid (killing suppressor-killing determinant) might function as a plasmid rescue system and not as a PSK system, but this remained to be validated. Here, we aimed to clarify unsettled mechanistic aspects of Kid activation, and of the effects of this for kis-kid–bearing plasmids and their host cells. We confirm that activation of Kid occurs in cells that are about to lose the toxin-encoding plasmid, and we show that this provokes highly selective restriction of protein outputs that inhibits cell division temporarily, avoiding plasmid loss, and stimulates DNA replication, promoting plasmid rescue. Kis and Kid are conserved in plasmids encoding multiple antibiotic resistance genes, including extended spectrum β-lactamases, for which therapeutic options are scarce, and our findings advise against the activation of this TA pair to fight pathogens carrying these extrachromosomal DNAs.Plasmids serve as extrachromosomal DNA platforms for the reassortment, mobilization, and maintenance of antibiotic resistance genes in bacteria, enabling host cells to colonize environments flooded with antimicrobials and to take advantage of resources freed by the extinction of nonresistant competitors. Fueled by these selective forces and aided by their itinerant nature, plasmids disseminate resistance genes worldwide shortly after new antibiotics are developed, which is a major clinical concern (1–3). However, in antibiotic-free environments, such genes are dispensable. There, the cost that plasmid carriage imposes on cells constitutes a disadvantage in the face of competition from other cells and, because plasmids depend on their hosts to survive, also a threat to their own existence.Many plasmids keep low copy numbers (CNs) to minimize the problem above, because it reduces burdens to host cells. However, this also decreases their chances to fix in descendant cells, a new survival challenge (4). To counteract this, plasmids have evolved stability functions. Partition systems pull replicated plasmid copies to opposite poles in host cells, facilitating their inheritance by daughter cells (5). Plasmids also bear postsegregational killing (PSK) systems, which encode a stable toxin and a labile antitoxin (TA) pair that eliminates plasmid-free cells produced by occasional replication or partition failures. Regular production of the labile antitoxin protects plasmid-containing cells from the toxin. However, antitoxin replenishment is not possible in cells losing the plasmid, and this triggers their elimination (5).TA pairs are common in plasmids disseminating antibiotic resistance in bacterial pathogens worldwide (2, 6–10). The link of these systems to PSK and the exiguous list of alternatives in the pipeline have led some to propose that chemicals activating these TA pairs may constitute a powerful antibiotic approach against these organisms (5, 11–13). However, the appropriateness of these TA pairs as therapeutic targets requires unequivocal understanding of their function in plasmids. Although PSK systems encode TA pairs, not all TA pairs might function as PSK systems, as suggested by their abundance in bacterial chromosomes, where PSK seems unnecessary (14–16). Moreover, the observation that many plasmids bear several TA pairs (6–10) raises the intriguing question of why they would need more than one PSK system, particularly when they increase the metabolic burden that plasmids impose on host cells (17). Because PSK functions are not infallible, their gathering may provide a mechanism for reciprocal failure compensation, minimizing the number of cells that escape killing upon plasmid loss (5). Alternatively, some TA pairs may stabilize plasmids by mechanisms different from PSK, and their grouping might not necessarily reflect functional redundancy (18).This may be the case in plasmid R1, which encodes TA pairs hok-sok (host killing-suppressor of killing) and kis(pemI)-kid(pemK) (19–23). Inconsistent with PSK, we had noticed that activation of toxin Kid occurred in cells that still contained R1, and that this happened when CNs were insufficient to ensure plasmid transmission to descendant cells. We also found that Kid cleaved mRNA at UUACU sites, which appeared well suited to trigger a response that prevented plasmid loss and increased R1 CNs without killing cells, as suggested by our results. In view of all this, we argued that Kid and Kis functioned as a rescue system for plasmid R1, and not as a PSK system (24). This proposal cannot be supported by results elsewhere, suggesting that Kid may cleave mRNA at simpler UAH sites (with H being A, C, or U) (25, 26), a view that has prevailed in the literature (14, 16, 27–29). Moreover, other observations indicate that our past experiments may have been inappropriate to conclude that Kid does not kill Escherichia coli cells (30, 31). Importantly, Kid, Kis, and other elements that we found essential for R1 rescue are conserved in plasmids conferring resistance to extended-spectrum β-lactamases, a worrying threat to human health (1, 6–10, 32). Therapeutic options to fight pathogens carrying these plasmids are limited, and activation of Kid may be perceived as a good antibiotic alternative. Because the potential involvement of this toxin in plasmid rescue advises against such approach, we aimed to ascertain here the mode of action; the effects on cells; and, ultimately, the function of Kid (and Kis) in R1.     

Glycosylated haemoglobin is markedly elevated in new and known diabetes patients with hyperglycaemic ketoacidosis

Background

Glycosylated haemoglobin (HbA1c) and random blood glucose are markers of chronic and acute hyperglycaemia respectively.

Objective

We compared HbA1c levels in ketoacidosis (DKA) occurring in known and newly diagnosed diabetes.

Methods

Retrospective review of medical records for 83 DKA admissions in 2008 and 2009 with results for HbA1c at presentation

Results

There were 52 and 31 DKA admissions in known and newly diagnosed diabetes patients respectively. Fifty of the 83 DKA admissions were in females. The mean age (per admissions) and HbA1c of all admissions are 43.4 ± 20.3 years (n=83) and 12.7 ± 3.4 % (n=83) respectively. Mean HbA1c in known Type 1, known Type 2 and newly diagnosed diabetes patients were similarly very high: 12.4 ± 3.3 %, 12.5 ± 3.3 %, 13.1 ± 3.7 %; P = 0.6828. The HbA1c levels in newly diagnosed diabetes patients less than 30 years (likely Type 1 diabetes) and ≥ 30 years (likely Type 2 diabetes) were similar. There was a tendency to significantly positive correlation between blood glucose and HbA1c in new diabetes patients.

Conclusions

In our setting, DKA is associated with markedly elevated HbA1c levels in known type 1, known type 2 and new onset diabetes.     

Hygiene practices in abattoir and slaughter slab,determinants and assessment of abattoir and slaughter slab facilities in Abakaliki,Ebonyi State South-East Nigeria

BackgroundWorkers in slaughterhouses engaging in unhygienic practices create conducive environments for zoonoses and meat contamination. Knowledge of hygiene practices and their determinants provides evidence for the design of targeted interventions.ObjectivesWe investigated knowledge and determinants of hygiene practices among workers in slaughterhouses and assessed slaughterhouse facilities in Abakaliki.MethodsWorkers in the Central Meat Market abattoir and Slaughter slab Abakaliki were interviewed in a cross-sectional quantitative study to ascertain their knowledge and hygiene practices while abattoir facilities were assessed using a checklist. Associations were analysed with Chi-square while predictors were determined using binary logistic model.ResultsWe interviewed 188 workers 75.5% and 85.6% of whom had good knowledge and good hygiene practices respectively. However, hand-washing before and after handling meat (44.1%), cleaning work surfaces with soap and water (45.2%) and sanitary disposal of waste (6.9%) were suboptimal. Knowledge of good hygiene practice was a predictor of good hygiene practice (AOR: 4.6, 95% CI: 2.0–11.3, p=0.001). Well water and borehole were present in both slaughterhouses and cold rooms were available in Central Meat market abattoir.ConclusionsThe level of good knowledge was high and this was a determinant of good hygienic practices. Training on hygiene practices is recommended to prevent meat contamination and zoonoses.