Analyzing RNA posttranscriptional modifications to decipher the epitranscriptomic code.

The discovery of RNA silencing has revealed that non-protein-coding sequences (ncRNAs) can cover essential roles in regulatory networks and their malfunction may result in severe consequences on human health. These findings have prompted a general reassessment of the significance of RNA as a key player in cellular processes. This reassessment, however, will not be complete without a greater understanding of the distribution and function of the over 170 variants of the canonical ribonucleotides, which contribute to the breathtaking structural diversity of natural RNA. This review surveys the analytical approaches employed for the identification, characterization, and detection of RNA posttranscriptional modifications (rPTMs). The merits of analyzing individual units after exhaustive hydrolysis of the initial biopolymer are outlined together with those of identifying their position in the sequence of parent strands. Approaches based on next generation sequencing and mass spectrometry technologies are covered in depth to provide a comprehensive view of their respective merits. Deciphering the epitranscriptomic code will require not only mapping the location of rPTMs in the various classes of RNAs, but also assessing the variations of expression levels under different experimental conditions. The fact that no individual platform is currently capable of meeting all such demands implies that it will be essential to capitalize on complementary approaches to obtain the desired information. For this reason, the review strived to cover the broadest possible range of techniques to provide readers with the fundamental elements necessary to make informed choices and design the most effective possible strategy to accomplish the task at hand.

Prevalence of undiagnosed atrial fibrillation in elderly individuals and potential cost-effectiveness of non-invasive ambulatory electrocardiographic screening: The ASSERT-III study.

BACKGROUND: In approximately 10% of patients with implanted pacemakers or defibrillators, previously unrecognized atrial fibrillation (AF) is detected within 3 months. It is unknown whether elderly patients without implanted devices have a similar prevalence of undiagnosed AF using non-invasive ECG monitoring, and if this approach to screening in this population is cost-effective. METHODS: Individuals ≥80 years old attending outpatient clinics without a history of AF and with hypertension and one additional risk factor underwent 30 days of continuous ECG monitoring with an option for an additional 30 days of monitoring if no AF was detected. The primary outcome was AF ≥ 6 min. Cost-effectiveness to prevent stroke was estimated using a Markov model based on observed AF detection rates and data from the published literature. RESULTS: Among 129 patients enrolled, 100 initiated monitoring for an average duration of 36 ±â€¯21 days. The proportion of patients that completed at least 30 days of monitoring was 59%. Average age was 84 ±â€¯3 years and mean CHA2DS2-VASc score was 4.5 ±â€¯1.2. AF ≥ 6 min was documented in 14%, ≥6 h in 8%, and ≥24 h in 3%. One week of monitoring costed $50,000 per quality-adjusted life-year-gained, 30 days and 60 days of monitoring costed $70,000 and $84,000, respectively. CONCLUSIONS: Continuous non-invasive ECG monitoring is feasible in elderly patients. Undiagnosed AF is present in many elderly individuals, with 1 in 7 having episodes lasting ≥6 min. One week of monitoring may be cost-effective for stroke prevention in this population.

Design and rationale of the atrial fibrillation occurring transiently with stress (AFOTS) incidence study.

BACKGROUND: Atrial fibrillation (AF) is often detected for the first time in patients hospitalized for medical illness or non-cardiovascular surgery. AF occurring transiently with stress (AFOTS) describes this manifestation of AF, which may either be the result of a non-cardiac stressor, or existing paroxysmal AF that was not previously detected. Current estimates of AFOTS incidence are imprecise: ranging from 1 to 44%, owing to the marked heterogeneity in patient populations, identification and methods used to detect AFOTS. METHODS: The prospective, two-centre epidemiological AFOTS Incidence study will enroll 250 consecutive participants without a history of AF but with at increased risk of AF (Age ≥ 65 or >50 with one risk factor for AF) admitted to intensive care units (ICUs) for medical illness or non-cardiac surgery. Upon admission, participants will wear an ECG patch monitor that will remain in place for 14 days, or until discharge from hospital. Patients' consent to participation is deferred for up to 72 h after admission. The primary endpoint is the incidence of AF lasting ≥30 s. The study is powered to detect an AF incidence of 17% ±â€¯5%. RESULTS: We conducted a vanguard feasibility study, and 55 participants have completed participation. The median duration of monitoring was seven days. AF was detected by the clinical team in 8 participants (14%; 95% Confidence Interval 7-26%). CONCLUSIONS: The AFOTS Incidence study will employ a systematic and highly sensitive protocol for detecting AFOTS in medical illness and non-cardiac surgery ICU patients. This study is feasible and will provide a reliable estimate of the true incidence of AFOTS in this population.

Interactive effects of insomnia symptoms and trauma exposure on PTSD: Examination of symptom specificity.

OBJECTIVE: Although symptoms of posttraumatic stress disorder (PTSD) are common following exposure to a traumatic event, most people who experience trauma do not develop PTSD. Thus, the identification of risk factors that may interact with trauma exposure to confer vulnerability for the development of PTSD may highlight important targets for prevention and treatment. Recent research suggests that sleep disturbance amplifies the effect of maladaptive emotional processes on PTSD symptom severity. However, no study to date has examined the impact of sleep disturbance, such as insomnia symptoms, on the relationship between trauma exposure severity and specific PTSD symptom clusters. METHOD: The present study examined insomnia symptoms as a potential moderator of the relationship between trauma exposure severity and specific PTSD symptom clusters among combat exposed veterans (N = 72). RESULTS: Results revealed large associations between insomnia symptoms and PTSD symptom clusters, small to moderate associations between combat trauma severity and PTSD symptom clusters, and a significant interaction between insomnia symptoms and combat exposure to predict reexperiencing, but not avoidance or arousal, symptoms of PTSD. CONCLUSION: These findings suggest that poor sleep may be one risk context in which trauma exposure results in the development of reexperiencing symptoms of PTSD. The implications of these findings for the development and maintenance of reexperiencing symptoms of PTSD are discussed. (PsycINFO Database Record

Randomized study of growth factors post-peripheral-blood stem-cell transplant: neutrophil recovery is improved with modest clinical benefit.

PURPOSE: To evaluate the clinical value of growth factors (GFs) with peripheral-blood stem cells (PBSC) collected following mobilization with GFs, we randomized patients to receive or not to receive GFs following transplant. PATIENTS AND METHODS: Thirty-seven patients were apheresed after receiving the combination of granulocyte colony-stimulating factor (G-CSF) with granulocyte-macrophage colony-stimulating factor (GM-CSF) at doses of 10 micrograms/kg/d and 5 micrograms/kg/d, respectively, for 6 days before apheresis and during a median of 4 days of collections. One day after the infusion of autologous marrow and PBSC, patients were randomly assigned to receive no GFs or a combination of G-CSF (7.5 micrograms/kg/d) and GM-CSF (2.5 micrograms/kg/d), both as a 2-hour intravenous (i.v.) infusion twice per day until the neutrophil count was greater than 1,500/microL. RESULTS: The median days to recovery to an absolute neutrophil count (ANC) of 100/microL (9 v 11.5, P = .0005), 500/microL (10 v 16, P = .0004), or 1,000/microL (12 v 21, P = .0008) was shortened with the use of GFs, post-PBSC infusion. In addition, the duration of hospitalization was shorter (19 v 21 days, P = .0112) in the arm receiving GFs post-PBSC infusion. There was no significant difference between the two study arms in the duration of fever, documented septic episodes, or RBC or platelet transfusion requirements. CONCLUSION: Despite faster neutrophil recovery and shortened duration of hospitalization with GFs administered after PBSC transplantation, the measured clinical variables of febrile days, septic episodes, and transfusion requirements were similar between the study arms. The use of GFs post-PBSC transfusion is associated with a modest clinical benefit.

Randomized comparison of G-CSF + GM-CSF vs G-CSF alone for mobilization of peripheral blood stem cells: effects on hematopoietic recovery after high-dose chemotherapy.

Fifty patients with either lymphoid or selected solid tumor malignancies were apheresed an identical number of times for PBSC collection after being randomized to receive either G-CSF 10 microg/kg/day alone (arm I), or G-CSF at the same dose with GM-CSF 5 microg/kg/day (arm II). Growth factor(s) was/were given as the stem cell mobilizing agent for 5 days before the start of PBSC collection, and were continued throughout the 4 days of apheresis. Aspiration and cryopreservation of autologous bone marrow occurred on day 3 or 4 of growth factor(s). Thirty-one of 50 patients received one cycle only at time of evaluation, and 19 patients received two cycles of HDCT, each supported with PBSC with or without autologous bone marrow. No patients received growth factors post-autologous stem cell transplant, unless the absolute neutrophils count (ANC) failed to recover to > or = 100/microl by day +18 post-transplant. The median number of days to recovery of ANC to 100/microl, 500/microl and 1000/microl, and of platelet counts to 20000/microl, 50000/microl and 100000/microl after either cycle 1 or cycle 2 of HDCT and the number of febrile days and platelet and PRBC transfusion requirements was not significantly different between the two arms of the study. The duration of hospitalization was similar between study arms for cycle 1 of HDCT, but was 3.5 days less with arm II compared to arm I (P = 0.0248) for cycle 2 of HDCT. The bone marrow buffy coat and PBSC product mononuclear cell count (x 10(8)/kg) and CD34+ cell count (x 10(6)/kg) collected by each method of stem cell mobilization was not significantly different. There is questionable clinical benefit with PBSC products mobilized with the combination of G-CSF and GM-CSF vs G-CSF alone. Perhaps different dosages, schedules, or other growth factor combinations with G-CSF might enhance these differences.

Antifungal effects of yeast-derived rhu-GM-CSF in patients receiving high-dose chemotherapy given with or without autologous stem cell transplantation: a retrospective analysis.

Systemic fungal infections (SFI) in patients receiving high-dose chemotherapy (HDC) are a frequent cause of morbidity and mortality. Preclinical studies have reported augmented antifungal activity of monocytes, macrophage cells, and neutrophils exposed to certain colony-stimulating factors (CSF), including GM-CSF. We conducted a retrospective descriptive epidemiologic study to examine the characteristics of 145 consecutive patients receiving HDC administered with or without autologous stem cell transplantation (ASCT) and who subsequently received either GM-CSF and G-CSF, G-CSF alone, GM-CSF +/- IL-3 or no CSF. The analysis of this patient population sought to define the incidence of SFI and its relationship to therapy with monocyte/macrophage-stimulating (MMS group) cytokines (GM-CSF and G-CSF; GM-CSF +/- IL-3) or to cytokines which do not result in monocyte/macrophage stimulation (NMMS group, G-CSF alone or no CSF). Risk factors for the development of SFI were balanced between the MMS (n = 70) and NMMS (n = 75) groups. Two patients (2.9%) in the MMS and nine patients (12%) in the NMMS groups developed SFI. The risk ratio for developing SFI in the NMMS group compared to the MMS group was 4.20 (P = 0.023). This relationship was confounded, however, by the diagnosis of hematologic tumor or solid tumor (RR = 3.15, P = 0.082). SFI was the primary cause or major contributing factor in five of the 10 total deaths in our study population. Four SFI-related deaths occurred in the NMMS group and one SFI-related death occurred in the MMS group. Our data suggest a protective role for GM-CSF, IL-3 or other MMS cytokines in preventing SFI in patients receiving HDC. This should be further investigated as a potential complementary approach to conventional strategies in antifungal prophylaxis for patients receiving HDC.

An improved parasitological technique for the diagnosis of African trypanosomiasis.

Light microscopic examination of the buffy coat zone of a microhaematocrit capillary tube expressed on to a slide was found to be consistently more reliable than other standard techniques in detecting trypanosomes in the circulation of cattle. This method alaos allowed identification of different trypanosome species. Optimal results were obtained using darkground illumination.

Introduction to immunology.

The immune system is a complex network of components functioning to provide host defense. This network consists of immunologic cells and their products (e.g., interleukins and colony-stimulating factors), organs, tissues, complement, and major histocompatibility complex antigens. These components are organized into specific and nonspecific immune systems, the major functional activities of which include antigen presentation and cell-mediated cytotoxicity.

Bone marrow granulomas possibly associated with amiodarone.

Amiodarone is a class III antiarrhythmic agent that is effective in treating different types of cardiac dysrhythmias. It was approved only for treatment of life-threatening ventricular dysrhythmias refractory to other therapy; however, its use for atrial dysrhythmias such as atrial fibrillation is well accepted. Adverse effects associated with amiodarone include pulmonary, hepatic, thyroid, ocular, and neurologic toxicities. Our patient experienced intermittent fever, night sweats, and fatigue while taking the drug for treatment of atrial fibrillation. Bone marrow biopsy showed granuloma formation after 17 months of therapy with amiodarone. Amiodarone was discontinued due to significant hypotension and shortness of breath. To our knowledge, this is the third case report of granuloma formation in bone marrow possibly associated with this agent.

Cervical spinal cord stimulation for spasticity in cerebral palsy.

A prospective double-blind study of high cervical spinal cord stimulation conducted in eight moderately disabled, spastic, cerebral palsied children failed to demonstrate any significant improvement over base line function during chronic spinal cord stimulation at either optimal stimulation parameters or random placebo parameters. Chronic stimulation included 4 consecutive months of stimulation for 24 hours each day. Stimulators were randomly programmed at optimal parameters for 2 of the 4 months and at placebo parameters for the remaining 2 months. At the end of each month of chronic stimulation, subjects were assessed with a multidisciplinary test battery that included a self-assessment, specific clinical examinations, tests of gross and fine motor control, neuropsychological and neurophysiological tests, a detailed gait analysis, and video recordings. By 6 months after the completion of the study, only 1 of the 8 subjects continued to use his stimulator on a regular basis, with minimal benefit.

Cervicothoracic vascular injuries.

Arterial and venous trauma of the cervicothoracic region continues to present challenging problems for the surgeon, despite advances in vascular diagnostics and surgical technique. Whether due to penetrating or blunt mechanisms, overall incidence of these injuries is low, whereas morbidity and mortality remain high. Despite collective experience from busy trauma centers, there still remain controversies regarding diagnostic evaluation, operative approach, and surgical treatment of these potentially devastating injuries. Therefore, this article compares and contrasts recent literature and controversies surrounding the treatment of cervicothoracic trauma. Pros and cons of duplex ultrasonography and angiography in the diagnosis of carotid and vertebral artery injury are highlighted, and selective versus mandatory neck exploration for zone II penetrating injuries are discussed. Increasing awareness of blunt carotid artery injury is emphasized, including management dilemmas that frequently accompany this type of injury. In addition, we review interventional radiological techniques for the management of vertebral artery injury and surgical approaches for aortic arch branch vessel or major cervicothoracic vein injury.

Limited dorsiflexion predisposes to injuries of the ankle in children.

Injuries to the ankle are common in children. We investigated whether decreased dorsiflexion predisposes to such fractures and sprains. Passive dorsiflexion in children with ankle injuries was compared with that in a control group of patients with a normal ankle. The uninjured side was examined to determine flexibility in those patients with ankle injuries. In 82, the mean dorsiflexion was 5.7 degrees with the knee extended and 11.2 degrees with the knee flexed. In 85 controls, the mean dorsiflexion was 12.8 degrees with the knee extended and 21.5 degrees with the knee flexed (p < 0.001, Student's t-test). There was a strong association between decreased ankle dorsiflexion and injury in children. A flexible triceps surae appeared to absorb energy and protect the bone and ligaments, while stiffness predisposed to injury. We suggest that children with tight calf muscles should undergo a regimen of stretching exercises to improve their flexibility.

The blood volumes and erythrokinetics of Ndama and Zebu cattle experimentally infected with Trypanosoma brucei.

The responses of susceptible Ndama and Zebu cattle to experimental infection with Trypanosoma brucei were compared using haematological, parasitological and radioisotopic methods. Animals of both breeds became anaemic, but this was more severe in the Zebu cattle, one of which died. Although the prepatent period was the same in animals of both breeds, the levels of the first and subsequent peaks of parasitaemia were higher in the Zebu. The anaemia was due to an accelerated rate of red cell break-down which was more marked in the Zebu cattle. Haemodilution was not a feature. There was no evidence of dyshaemopoiesis but iron reutilisation from degraded erythrocytes was impaired. The greater resistance of the Ndama to T brucei infection could not be attributed to the capacity of this breed to mount a more effective erythropoietic response than the Zebu.

Susceptibility to African trypanosomiasis of N'Dama and Zebu cattle in an area of Glossina morsitans submorsitans challenge.

The use of trypanotolerant livestock is considered to be an important strategy for the control of African animal trypanosomiasis. In order to define the extent of the differences in susceptibility and productivity, 10 Zebu cows (a breed considered trypanosusceptible) and 10 N'Dama cows (a breed recognised for trypanotolerance) were exposed to a natural field challenge from Glossina morsitans submorsitans Newstead. The animals were two-and-a-half to three years old and had not been previously exposed to trypanosomiasis. All Zebu died of trypanosomiasis within eight months of first exposure. In contrast, only three N'Dama died of trypanosomiasis; they had all been suckling calves before they succumbed 11 to 14 months after initial exposure. The prevalence, level and duration of parasitaemia were significantly less in the N'Dama, which, unlike the Zebu, did not become febrile during parasitaemia. The differences in parasitaemia were largely attributable to Trypanosoma vivax. The N'Dama also developed much less severe anaemia than the Zebu. The mean and standard deviation of the packed red cell volume of the N'Dama was not significantly different between eight months after exposure when all Zebu were dead, and 21 months when the experiment was terminated. The relative productivity of the N'Dama was impressive. In addition to reduced mortality, the N'Dama experienced no abortions and produced five calves, three of which were alive at the end of the experiment, at which time three of the surviving N'Dama were pregnant. In the Zebu, in marked contrast, abortions occurred both in early and late pregnancy and no live calves were produced. The study confirmed that N'Dama cattle are innately less susceptible to trypanosomiasis than Zebu cattle and can survive and be productive in endemic areas of trypanosomiasis where Zebu perish.