Amidst the battle for supremacy, our army of immune cells relentlessly wages war against various pathogens, especially superbug bacteria. Despite the pool of ample winnings, our body still experiences defeat from time to time. We succumb to diseases as the war reels its favor towards the tenacious pathogens. Of course, we cannot allow our immune defense to be utterly defeated. Otherwise, we’d be dead. As bacteria advance by taking over much space and nutrients inside our body, we get external help through antimicrobial chemicals that scientists continue to contrive. Unfortunately, antibiotic resistance has surfaced and turned certain strains of bacteria into a superbug – one that has become resistant to the effects of antibiotics.
Chemical warfare prior to the rise of a superbug
Antimicrobial chemicals, particularly antibiotics, came into existence as chemicals that were strategically designed and produced with the intent of killing pesky bacteria. In 1928, penicillin was discovered, which led to its use as the first natural antibiotic capable of undermining a spectrum of bacteria, if not by killing, by inhibiting their growth. Its role as a wonder drug against various bacteria caused Alexander Fleming to receive a duly recognition by winning a Nobel prize award for its discovery. Soon, more antibacterial agents came up to our defense. Antibiotics, such as penicillin and cephalosporin, destroy bacterial cell wall whereas polymyxins target bacterial cell membrane. Rifamycin, quinolones, sulfonamides, and the likes interfere with the enzymes essential to bacteria. Once again, we gained an upper hand.
Bacteria resisting: the rise of a superbug
While we thought we finally came up with a powerful weapon, the bacteria conjured up an amazing strategy to work in their favour — antibiotic resistance. Some of them started to morph. They evolved and mutated into new strains referred to as superbug. They became capable of resisting the drugs’ antimicrobial effects. One of their strategies is to produce β-lactamases that destroy the structure of β-lactam antibiotics (e.g. penicillin and cephalosporin). The bacteria that evolved into superbug organisms did not just live; they thrived. They multiplied and passed on to the next generation the features that could withstand a number of antibiotics.
DNA uptake by superbug bacteria
Apart from the vertical gene transfer of genes, antibiotic resistance could also be transferred through horizontal gene transfer. It is a mechanism whereby genes are taken up or transposed from one species to another, and one of the possible explanations for the rise of superbug bacteria. DNA uptake by a bacterial cell was captured for the first time in a video by a team of scientists from Indiana University. In the video1, it shows how a bacterial cell takes up DNA fragments from dead bacterial cells through its pilus. Like a harpoon, the pilus was used by the bacterium, Vibrio cholera, to catch and reel a stray DNA fragment, and then bring it inside the bacterial cell via the same pore on its cell wall. It, then, incorporates the DNA into its own genome. Accordingly, this is probably one of the mechanisms for a bacterium to turn into a superbug.
First video evidence of DNA uptake by Vibrio cholera.
(Video credit: Ankur Dalia, Indiana University, uploaded on YouTube by Group IU Biology News)
A researcher from the team, Courtney Ellison, recounted, “The size of the hole in the outer membrane is almost the exact width of a DNA helix bent in half… If there weren’t a pilus to guide it, the chance the DNA would hit the pore at just the right angle to pass into the cell is basically zero.” It appears that the pilus takes a crucial role in horizontal gene transfer. If left to chance the DNA fragment would not easily get inside the cell since the pore was too small for it to fit. Through horizontal gene transfer, those that were once sensitive to the antibiotic could later become superbug bacteria as well. As Ankur Dalia, another researcher from the same team, pointed out, “Horizontal gene transfer is an important way that antibiotic resistance moves between bacterial species….” The video that the research team captured for the first time could explain how antibiotic resistance can be acquired from one superbug bacterial species to another.
The battle is far from over. The antibiotic resistance already raised global concerns as it has rendered certain antibiotics ineffective. Pathogenic superbug bacteria have successfully armed themselves with genes that could neutralize antibiotic effects. Fortunately, scientists do not waver in determining the strategies that superbug bacteria exploit. The recent discovery of the way by which bacteria employ to make them antibiotic-resistant superbug strains could lead to better therapeutic strikes that could counter them, hopefully, with ample success.
— written by Maria Victoria Gonzaga
1 Indiana University. (2018). IU scientists watch bacteria ‘harpoon’ DNA to speed their evolution. Retrieved from https://news.iu.edu/stories/2018/06/iub/releases/11-scientists-watch-bacteria-harpoon-dna-to-speed-their-evolution.html
When someone says “I could die of a broken heart…”, chances are, that person may be truly risking life from a broken heart – a condition referred to as broken heart syndrome. The emotional agony can be likened to a physical pain. Apparently, it was only recently that it gained stalwart attention from researchers as they began to probe the pathobiology behind a broken heart syndrome.
Broken heart syndrome – overview
Hearing stories of a person in severe emotional distraught from a loved one’s death and then died not long after is not uncommon. How much of losing a loved one, a gut-wrenching rejection, or an austere betrayal could lead to death no longer surprise us. Deep sorrow certainly takes a toll. Death is inevitable but dying from a broken heart syndrome is something that is treatable and preventable, thus, is escapable. Inopportunely, the pathobiological aspect of a broken heart syndrome has not been fully unmasked. What is known about it so far is the fact that severe emotional stress is capable of triggering the transient weakening of the heart muscle, turning the latter fatally dysfunctional.
Pathology of Broken heart syndrome
The medical term for broken heart syndrome is takotsubo cardiomyopathy. The condition was first described in Japan in 19901 and the name is derived from”takotsubo“, which when translated means an “octopus trap“. It is so because the left ventricle of the heart of a person with broken heart syndrome is shaped like a contraption pot used for catching octopuses. Its apex balloons or bulges out while its base remains as is. As a result, the heart with temporarily enlarged apical ventricle cannot function as it should. Consequently, blood is not pumped properly and this leads to angina (chest pain) and shortness of breath, which are symptoms typical of a heart attack. Because of this, broken heart syndrome can be easily mistaken as a heart attack. The difference lies in the arteries. A true heart attack is due to an occlusion in the artery. In broken heart syndrome, arteries are not obstructed. Also, the ventricle is only temporary dysfunctional and therefore may normalize again if given enough time to rest and recuperate.
Biology of a broken heart syndrome
Unraveling the mysteries of broken heart syndrome is a recent biological pursuit. Consequently, the precise mechanism is not yet clear. Experts presume a surge in adrenaline and other stress hormones since the condition is often associated with emotional stressful events (n.b. it has also been reported to happen during euphoric events, e.g. winning a lottery). The overwhelming presence of these hormones might have stunned the heart and triggered structural changes in the myocytes and/or the coronary blood vessels.2 In a study published in Psychoneuroendocrinology, researchers found that bereaved individuals have higher levels of pro-inflammatory cytokines.3
A person who went through a broken heart syndrome and survived it could attest how the struggle had been real. Having to go through an intensely stressful event could plausibly cloud one’s drive and enthusiasm for life. Research on the pathobiology behind broken heart syndrome is understandably new, and as such inadequate for now.
— written by Maria Victoria Gonzaga
1 Akashi, Y.J., Nef, H.M,, Möllmann, H., & Ueyama, T. (2010). “Stress cardiomyopathy”. Annu. Rev. Med. 61: 271–86. Doi:10.1146/annurev.med.041908.191750
2 Harvard Women’s Health Watch. (2018). Takotsubo cardiomyopathy (broken-heart syndrome). Retrieved from https://www.health.harvard.edu/heart-health/takotsubo-cardiomyopathy-broken-heart-syndrome.
3 Fagundes, C.P., Murdock, K.W., LeRoy, A., Baameur, F., Thayer, J.F., & Heijnen, C. (2018). Spousal bereavement is associated with more pronounced ex vivo cytokine production and lower heart rate variability: Mechanisms underlying cardiovascular risk? Psychoneuroendocrinology 93:65-71. doi: 10.1016/j.psyneuen.2018.04.010.
Respiratory failure is an outcome from inadequate gas exchange wherein arterial oxygen and carbon dioxide not at normal levels. A drop of oxygen is called hypoxemia while the rise in arterial carbon dioxide is hypercapnia. Respiratory failure includes abnormal blood gases, increased of breathing and increased respiratory rate. In obstetric patients a complicated conditions occurs resulting to various complications and several physiological changes. That is why risk of complication in pregnancy with respiratory failure considered challenge for positive maternal and neonatal outcomes.
Causes in Maternal Respiratory failure
The main causes of respiratory failure were postpartum hemorrhage, peripartum period, preeclampsia and pneumonia during pregnancy. In which the oxygen reserve impairment during pregnancy causes fast desaturation leading to fetal hypoxia. Many of the patients showed improvement after delivery in partial pressure of arterial oxygen. But some exhibited high incidence of neonatal respiratory distress syndrome. Neonatal complications were commonly caused by sepsis and meconium aspiration syndrome as well as impairment in neurological development.
Acute respiratory distress syndrome is classified as mild to severe injuries from aspiration, trauma and multiple transfusions. It is also a condition of newborn having dyspnea with cyanosis that is often related to surfactant deficiency. However, preterm infant retinas showed incomplete retinal vascularization. On the other hand obstetric patients showed 74% having maternal respiratory failure complications while 25.4% to non-obstetric patients.
Indeed, early delivery might improve maternal oxygenation and reduce mortality rate. However maternal respiratory failure may not always improve after the delivery wherein deleterious sepsis and lung injury persist after delivery. Additionally a detailed examination is needed to follow up the neonates in the future. Using the risk categories whether normal, questionable and abnormal, if the mental developmental index is <70 then the neonates are suspected to have mental retardation.
Source: Prepared by Joan Tura from Journal of the Formosan Medical Association
Volume 117, Issue 5, May 2018, Pages 413-420
Leptospirosis is a corkscrew shaped that is known as one of the most widespread bacterial zoonoses in the world. Symptoms range from mild flu to severe multi-organ failure and fatal pulmonary hemorrhagic syndrome. In which the key factors of these diseases are from stray animals, poor sanitation, rodents, heavy rainfall and flooding. Many regions have been increasingly exposed to leptospirosis infection due to climate change, global warming, poverty and high urban density. Rodents are the main animal reservoir in urban settings mainly involved in pathogenic transmission. Moreover, a high prevalence in rodent population occurs in major cities such as in Baltimore, Tokyo and Copenhagen. In Italy sporadic cases of leptospirosis have been often related to river flooding. This study focused on molecular survey of rodents in the city of Palermo, Italy.
Human leptospirosis cases
Two cases in 2009 of leptospirosis in Palermo during spring and fall seasons and there were 22 locations monitored. A rodent is the main reservoir for leptospirosis related to heavy rainfall and flooding in urban streets and riverbanks. During street floods individual were potentially in contact with water contaminated by infected rodent urine. So, the risk of infection is high but because of good hygienic conditions and economic wellness severe symptoms is rare. It is also possible that periodic exposures to serovars leave the immune competent population more resistant to infection. Other cases also in Northern Italy an elderly woman has a fatal infection after river flooding occurs.
Based on molecular testing leptospirosis are positive in all species of wild rodents living in almost all areas in the city. Mice and rats are the natural source for this pathogenic infection. The main common problem in Palermo, Italy is the urban street floods from heavy rains and waste accumulation. In which the city is represented by almost ten thousand stray dogs feeding on garbage. Previously, a patient was in contact with contaminated water in street flood after violent cloudburst. Waste collection also is one of the problem in Palermo that eventually facilitates the increased of rodent population.
High prevalence of leptospirosis occurs in mild wet climate, flooding of urban streets and socio-economic problems. Other Italian cities has presence of simultaneous risk factors for leptospirosis, and thus, a major concern from this underestimated zoonosis should be considered by public health authorities and clinicians particularly for elderly and immune-compromised individuals. However, severe symptomatic cases are referred to hospitals and the true prevalence of infection is probably not evaluated.
Source: Prepared by Joan Tura from Journal of Infection and Public Health
Volume 11, Issue 2, March–April 2018, Pages 209-214
Essential fatty acids, such as omega-3 and omega-6, are fatty acids that are polyunsaturated due to the multiple double bonds in their biochemical structure. As a fatty acid, they are basically a hydrocarbon chain with a carboxylic acid on one end and a methyl group on the other end. The methyl end of the chain is referred to as “omega”. Thus, omega-3 and omega-6 fatty acids got their names based on where the first double bond between two carbon molecules occurs from the methyl end of the hydrocarbon chain. This means omega-3 fatty acid is the essential fatty acid whose first double bond occurs between the third and the fourth carbon molecules whereas the omega-6 fatty acid is one in which the first double bond is between the sixth and the seventh carbon molecules.1, 2
Why essential fatty acids are essential
Essential fatty acids, particularly omega-3 and omega-6, are labeled as essential because we need them for various biological processes but our body is not equipped to produce them. We lack desaturase enzymes, which catalyze the insertion of double bonds distinctive of omega-3 and omega-6. We can only obtain these essential fatty acids by consuming food containing them. Some of the good sources are fish, seeds, bananas, nuts, and vegetable oils. In humans, α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are the three most notable omega-3 fatty acids whereas linoleic acid (LA) is one of the most important forms of omega-6 fatty acids.1, 2 However, how much of the essential fatty acids we need daily varies according to what our body requires. Our body needs them in an amount based on several confounding factors. Some of the factors to consider are physical activity and the time of the year.3
Biological importance of essential fatty acids omega-3 and omega-6
The essential fatty acids, omega-3 and omega-6, are important in the diet because of their various biological roles. The biochemical processes in which they take a part of are mostly associated with the regulation of the inflammatory responses of the body. For instance, they form the precursors to prostaglandins, thromboxane, leukotrienes, lipoxins, and resolvins. The essential fatty acids are also involved in cell signaling, e.g. by modulating lipid rafts in cell membranes. Furthermore, the essential fatty acids, and their metabolites, have been found to: (1) modulate the activities of angiotensin-converting and HMG-CoA reductase enzymes, (2) act as nitric oxide enhancers, (3) serve as β-blockers, (4) enhance diuresis, (5) enhance insulin action, (6) enhance insulin action, and (7) function as anti-atherosclerotic molecules.4
Essential fatty acids: the omega-6: omega-3 ratio
Too much of anything, no matter how good they are for health, can turn out bad. The essential fatty acids omega-3 and omega-6 can turn against us especially when taken in wrong proportions. They are unsaturated fats and therefore they are tagged as the healthy fats since they are “good for the heart”. Omega-3 fatty acids, most especially, have been associated with increasing high density lipoprotein (HDL, the good cholesterol) while decreasing low density lipoprotein (LDL, “the bad cholesterol”). However, a great disparity between the amount of omega-6 and omega-3 in the diet could be detrimental to health. Too much omega-6 while too little of omega-3 in the diet has been linked to increased risk to chronic inflammation and cancers such as breast, prostate, and colorectal. In contrast, more omega-3 fatty acids than omega-6 promoted anti-inflammation and decreased risk to cancer.3, 5
No consensus has been reached yet as to the proper omega-6: omega-3 fatty acid ratio. However, researchers recommend the ratio from 1:1 or 2:1 to 5:1 of omega-6 fatty acid to omega-3 fatty acid.5 More studies in this regard are needed. A healthy ratio of these essential fatty acids appears to be a key to proper biological functions and decreased risk to certain life-threatening health conditions.
— written by Maria Victoria Gonzaga
1 “Omega-3 fatty acid”. (n.d.). Biology-Online Dictionary. Retrieved from https://biology-online.org/dictionary/Omega-3_fatty_acid
2 “Omega-6 fatty acid”. (n.d.). Biology-Online Dictionary. Retrieved from https://biology-online.org/dictionary/Omega-6_fatty_acid
3 DiPasquale, D. (2011). “Everything About Fat”. Sott.net. Retrieved from https://www.sott.net/article/230686-Everything-About-Fat
4 Das, U. N. (2006). Biological significance of essential fatty acids. J Assoc Physicians India. 54:309-19. https://pdfs.semanticscholar.org/ff75/7e0dbe0a14fc2810ba52b833a5682b02b09e.pdf
5 Huerta-Yépez, S., Tirado-Rodriguez, A. B., & Hankinson, O. (2016). Role of diets rich in omega-3 and omega-6 in the development of cancer. Bol Med Hosp Infant Mex. 73(6):446-456. doi: 10.1016/j.bmhimx.2016.11.001.
Intermittent fasting recently gained popularity as an alternative way to keep one’s weight in check. Its basic tenets, though, go against what we had been previously told – to never skip a meal, especially breakfast. We have been accustomed to eating “like a king” as soon as we wake up to prepare the body for the toils and turmoils of the day. Intermittent fasting, though, says that it is alright to put that first meal off until you reach the time window for “feasting”.
Intermittent fasting – overview
Intermittent fasting promises profound health benefits. Accordingly, it can slow down aging, boosts immune defense, and help shed the extra weight.1 All the health benefits are seized if it is done properly. Intermittent fasting is a cycle between a fasting period and a non-fasting period. It may be done in two ways: whole-day fasting and time-restricted eating. Whole-day fasting is the more stringent form. It entails a 24-hour fasting done twice a week (5:2 plan) or every other day (1:1 plan). Time-restricted eating is a daily cyclic period of 16 hours of fasting and 8 hours of non-fasting. The periods are flexible. The pattern can be 12:12 (i.e. equal periods of fasting and non-fasting) or 23:1 (wherein the non-fasting period is set for only one hour). There are no restrictions as to the amount and the kinds of food to eat although consumption of healthy food within the recommended amounts during the non-fasting period is ideal.
Intermittent fasting – recent studies
Kim and others conducted a research on mice and they found that intermittent fasting helped to kick-start the metabolism and to burn fat by generating body heat in mice. Further, they found that during the fasting period there was an increase in the expression of vascular growth factor, a biochemical essential in angiogenesis and in activating the anti-inflammatory macrophages in white adipose tissue.2 Intermittent fasting may also help improve the ability of intestinal stem cells to regenerate as observed in a study in both aged and young mice by MIT biologists. Accordingly, it seems to have induced a metabolic switch in the intestinal stem cells causing the cells to preferably break down fatty acids instead of glucose.3 These are just some of the studies implicating the potential benefits of intermittent fasting, such as body fat reduction, adipose thermogenesis, metabolic homeostasis, and the preferential utilization of fat-derived ketone bodies and free fatty acids as energy sources via ketogenesis.4
Intermittent fasting – is it for all?
In spite of the purported health benefits of intermittent fasting, this weight loss modality is not recommended for all. Instead of being beneficial, it may be detrimental to the health of those who are immunocompromised and underweight. 4 Thus, consulting a physician should be the initial step. The extent of the positive effects may also differ from one individual to another. Despite the various studies highlighting the health benefits of intermittent fasting, they were done mostly on rodent models. Therefore, further studies are required to validate such promising results in humans.
Unless substantial studies to corroborate the health benefits of intermittent fasting are presented, a window of doubt remains. If in time intermittent fasting proves to be beneficial it would still lead to further queries, e.g. which fasting cycle is the ideal. Also, the effects may vary between young and older people, or between men and women especially when hormones are taken into account. Thus, similar to other weight loss modalities, it is possible that intermittent fasting may work for some people but not for all.
— written by Maria Victoria Gonzaga
1Cohut, M. (2018). Intermittent fasting may have ‘profound health benefits’. Retrieved from https://www.medicalnewstoday.com/articles/321690.php
2 Kim, K.H., Kim, Y.H., Son, J.E., Lee, J.H., Kim, S., et al. (2017). Intermittent fasting promotes adipose thermogenesis and metabolic homeostasis via VEGF-mediated alternative activation of macrophage. Cell Research, 27: 1309-1326. https://www.nature.com/articles/cr2017126′>10.1038/cr.2017.126
3 Trafton, A. (2018). Fasting boosts stem cells’ regenerative capacity. Retrieved from http://news.mit.edu/2018/fasting-boosts-stem-cells-regenerative-capacity-0503
4 Longo, V. D., & Mattson, M. P. (2014). Fasting: Molecular Mechanisms and Clinical Applications. Cell Metabolism, 19 (2), 181–192. http://doi.org/10.1016/j.cmet.2013.12.008
Asthma is a common global health problem that affects at least 18% of the population worldwide. Some of real life surveys show that all outcomes remain suboptimal with persisting symptoms and quality of life impairment. Many of the patients however, taking regular medication particularly corticosteroids and some self-management strategies. But in recent development it used breathing techniques to help control the symptoms of asthma. There were evidences for the effectiveness of self-management education as well as self-guided programmes to be accessed. In order, to have it conveniently and inexpensively to people with asthma and deliver standardized interventions. In 2012 US Agency for Healthcare Research and Quality concluded that non-pharmacological techniques can improve asthma symptoms and reduced medication.
Breathing retraining for Asthma patients
Breathing retraining exercise is recommended in evidence-based guidelines as possible adjuvant treatment for asthma patients. Based on pragmatic randomised trial the study reveals that three sessions of face-to-face physiotherapist improved the symptoms. Also the self-guided digital audiovisual program is considered as an acceptable intervention method. The current systematic and Cochrane review shows that breathing retraining therapy is an effective treatment with suitable trained physiotherapist.
Asthma is improved by the routine face-to-face method of breathing retraining exercise which eventually progress the quality of life impairment. In agreement with the previous research there were no significant changes in airway obstruction or inflammation observed. Therefore, breathing retraining provides a technique for coping better with asthma, but not disease modifying. That is why, with this intervention it will reduced the intake of anti-inflammatory medication and acts as an adjuvant.
The breathing retraining will allow patients how to adjust ones behavior and embed the techniques into daily lives. Additionally, with the collaboration of Asthma UK a web-optimised version of the intervention for online used have been produced. In a way that such approaches indicates this evidence-based non-pharmacological intervention be offered to people with asthma despite current medication. There is a need to stress that this intervention is not a cure rather a means to improve quality of life.
Source: Prepared by Joan Tura from THE LANCET: Respiratory Medicine
Volume 6, Issue 1, January 2018, Pages 19-28
Nicotinamide riboside gained traction as a recent study conducted by a team of scientists from University of Colorado Boulder reported the first clinical trial research. The results implicate potential health benefits of nicotinamide riboside supplementation, especially among middle-aged and older adults. One of its major benefits is it boosts nicotinamide adenine dinucleotide (NAD+), which, in turn, is beneficial for healthy aging and in extending lifespan.
The biology of nicotinamide riboside
Nicotinamide riboside is one of the many forms of vitamin B3. Similar to other forms of vitamin B3, nicotinamide riboside is capable of boosting NAD+ in the body. Based on a pre-clinical study conducted by Trammel et al1, it appears that it is the most effective among the other forms in terms of increasing NAD+ levels. The study was also able to point out that nicotinamide riboside is the most effective in promoting sirtuins. A sirtuin is an enzyme involved in mitochondrial biogenesis and in the regulation of circadian clocks. It is also credited for its beneficial effects on calorie restriction. NAD+ precursors, such as nicotinamide riboside, are effective sirtuin activators. Nicotinamide riboside, therefore, has a role in the stimulation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α)-dependent mitochondriogenic pathway. It is also involved in promoting mitochondrial gene transcription and augmenting respiratory chain activity.2
Nicotinamide riboside for healthy aging
A recent study by Christopher Martens et al. presented proof that nicotinamide riboside supplementation led to an increase in NAD+ metabolism in healthy middle-aged and older adults. This was observed in a six-week randomized, double-blind, placebo-controlled crossover clinical trial of healthy individuals, aged 55 to 79. Half of them were given placebo while the other half, a 500mg-dose of nicotinamide riboside chloride twice daily, followed by a placebo. Based on the results from blood tests and physiological measures post-treatment, the supplement increased the levels of NAD+ by 60%.3 Increasing NAD+ in older adults is beneficial in terms of promoting healthy aging since NAD+ levels tend to decline with age. NAD+ is involved in a myriad of metabolic pathways, serving as a coenzyme in various redox reactions. It shuttles energy within the cell, particularly during cellular respiration. It is also a vital activator of sirtuins. Apart from NAD+ boost, nicotinamide riboside was also found to be associated with reduced blood pressure and arterial stiffness.3
Other nicotinamide riboside effects
Nicotinamide riboside as a form of vitamin B3 and a precursor to NAD+ may prove essential as a supplement that protects against DNA damage and oxidative damage, and therefore, it may also help avert cancer. It may also be useful in improving general health and in lowering the risk of cardiovascular diseases. At present, there are no ample reports on its side effects. Niacin (another form of vitamin B3) has been found to cause mild flushing (i.e. red, warm, itchy or tingling sensation). The flushing though is generally harmless and subsides within an hour or two. Nonetheless, no flushing has been reported with nicotinamide riboside supplementation. More studies, therefore, are vital in order to identify and delineate potentially undesirable effects of nicotinamide riboside.
Future of nicotinamide riboside supplementation
The recent study raised the benefits of nicotinamide riboside supplementation especially among older adults. It also suggested its potential use in modulating hypertension. However, Martens et al. pointed out that their results served as initial insight into the potential benefits. More studies in the form of clinical trials are warranted to establish the efficacy and the safety of long-term supplementation of nicotinamide riboside in humans.
— Written by Maria Victoria Gonzaga
1Trammell, S.A., et al. (2016). Nicotinamide riboside is uniquely and orally bioavailable in mice and humans. Nat. Commun. 7: (12948).
2Zeviani, M. (n.d.). Novel Therapies: Activation Of Biogenesis. Retrieved from [http://www.mrc-mbu.cam.ac.uk/projects/58/novel-therapies-activation-biogenesis].
3Martens, C.R., Denman, B.A., Mazzo, M. R., Armstrong, M. L., Reisdorph, N., Mcqueen, M.B., Chonchol, M., & Seals, D. R. (2018). Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD in healthy middle-aged and older adults. Nature Communications 9(1286 ). DOI: 10.1038/s41467-018-03421-7
Spinal infections increased since 1990’s due to aging populations, chronic debilitating diseases and higher number of immunocompromised hosts. Management of spinal infections is still challenging because symptoms are often non-specific which leads to delayed diagnosis. However local pain in the neck and back are the main common symptoms taking place in more than 90% patients. Only few of the patients experience fever and motion of the spine is limited due to localized pain and muscle spasm. One of the useful tools used for early diagnosis of spinal infection is the magnetic resonance imaging. And it is able to yield positive finding just after 3-5 days from the onset of disease
Laboratory Test and Imaging
Almost 90% of patients with spinal infection demonstrate an elevated erythrocyte sedimentation rate. It also showed local pain worsening, sepsis, fever, neurologic symptoms and new local pain following recent episode of sepsis. For the pathogens identified in cultured must have appropriate antibiotics for careful consideration of antimicrobial susceptibility and spinal tissue penetration. In radiographic finding almost 74% of patients shows narrowing of the disc space. By the time of 3-6 weeks from the onset of disease reveals destructive changes such as lytic lesions of endplate. In patients with M. tuberculosis infection shows bone destruction with bone atrophy.
Some indications for surgical treatment include neurologic deficit, spinal instability, progressive deformity, persistent infection and unbearable pain. However the gold standard in surgical treatment in most patients is an anterior radical debridement followed by bone grafting. On the other hand patients suspected to have spinal infection due to bacteria, identification of the causative agent is very important. Cultured must me initiated from blood and from locus of infection before administering antibiotic. The rate of pathogen obtained from the disc body varies from 41%-90% which is usually collected using biopsy.
Indeed, the posterior to anterior debridement and strut bone grafting are recently popular in spinal infection surgery. In which this method provides faster and more complete fusion and better bone correction. However in some cases recurrent infection occurs after spinal instrumentation.
Sources: Prepared by Joan Tura from Journal of Orthopaedic Science
Volume 23, Issue 1, January 2018, Pages 8-13
Daptomycin is a lipopeptide antibiotic used as treatment for systemic infections caused by gram-positive organisms. Its compound occurs naturally from soil. And its unique mechanism of action makes it useful in treating infections caused by multiple drug resistance bacteria. Daptomycin mode of action disrupts bacterial cell membrane and inserted into where it then aggregates. The aggregation alters the curvature of the membrane which then creates leaks of ions resulting to the bacterial cell death. However, data on the clinical outcomes with vascular graft infection patients treated with Daptomycin are limited. This study is the pioneer describing Daptomycin used in the treatment of vascular graft infections caused by gram-positive organisms.
Daptomycin on Vascular Graft Infections
It isa retrospective cohort study of patients diagnosed with VGI receiving Daptomycin during the period January 2010 to December 2012. A total of 1066 patients underwent surgery at tertiary level hospital and among of 72 developed surgical site infections. And 25 have vascular graft infection which then treated with Daptomycin. These patients had previously existing episode of acute renal failure with glycopeptides allergy. The average dose of Daptomycin is 6.1 mg/kg/day. Even though, the current guidelines of the Infectious Disease Society of America recommended 8-10mg/kg/day for complicated bacteremia and endocarditis.
Daptomycin is also associated with rifampicin into the biofilm created by gram-negative microorganisms. But all patients given with rifampicin in addition to Daptomycin showed remission of infection. Yet those who did not receive rifampicin only Daptomycin showed only 50% remission of infection. All the patients in this study did not develop muscle toxicity due to the administration of Daptomycin. Since muscle toxicity is mostly reported to be linked with Daptomycin. As well as other side effects such as pneumonia and eosinophilic were not observed.
However, it appears that treatment of VGI with Daptomycin alone has similar effects with other antibiotics but with fewer side effects. Indeed, the use of Daptomycin as an antibiotic treatment for VGI caused by gram-positive bacteria is effective and well tolerated. It may be also serves as an alternative treatment for vascular graft infections particularly in patients with peripheral arterial disease whom renal insufficiency is common.
Sources: Prepared by Joan Tura from International Journal of Infectious Diseases
Volume 68, March 2018, Pages 69-73