Safe and rapid radial hemostasis achieved using a novel topical hemostatic patch: Results of a first-in-human pilot study using hydrophobically modified polysaccharide-chitosan.

BACKGROUND: The transradial approach (TRA) for catheter interventions decreases vascular complications and bleeding versus transfemoral approach. Reducing time to hemostasis and preventing radial artery occlusion (RAO) following TRA are important and incompletely realized aspirations. OBJECTIVES: This first-in-human study sought to evaluate the efficacy of a novel, topically applied compound (hydrophobically modified polysaccharide-chitosan, hm-P) plus minimal required pneumatic compression, to achieve rapid radial arterial hemostasis in post-TRA procedures compared with de facto standards. MATERIALS AND METHODS: About 50 adult patients undergoing 6 French diagnostic TRA procedures were prospectively enrolled. At procedure completion, a topical hm-P impregnated patch was placed over the dermotomy and TR Band (TRB) compression was applied to the access site. This patch was used as part of a novel rapid deflation protocol with a primary outcome of time to hemostasis. Photographic and vascular ultrasound evaluation of the radial artery was performed to evaluate the procedural site. RESULTS: Time to hemostasis was 40.5 min (IQR: 38-50 min) with the majority of patients (n = 39, 78%) not requiring reinflation. Patients with bleeding requiring TRB reinflation were more likely to have low body weight and liver dysfunction, with absence of hypertension and LV dysfunction. The rate of RAO was 0% with predischarge radial artery patency documented in all patients using vascular ultrasound. One superficial hematoma was noted. No late bleeding events or cutaneous reactions were reported in the study follow-up. CONCLUSIONS: Topical application of hm-P in conjunction with pneumatic compression was safe and resulted in rapid and predictable hemostasis at the arterial puncture site.

Aluminum or Low pH - Which Is the Bigger Enemy of Barley? Transcriptome Analysis of Barley Root Meristem Under Al and Low pH Stress.

Aluminum (Al) toxicity is considered to be the most harmful abiotic stress in acidic soils that today comprise more than 50% of the world's arable lands. Barley belongs to a group of crops that are most sensitive to Al in low pH soils. We present the RNA-seq analysis of root meristems of barley seedlings grown in hydroponics at optimal pH (6.0), low pH (4.0), and low pH with Al (10 µM of bioavailable Al3+ ions). Two independent experiments were conducted: with short-term (24 h) and long-term (7 days) Al treatment. In the short-term experiment, more genes were differentially expressed (DEGs) between root meristems grown at pH = 6.0 and pH = 4.0, than between those grown at pH = 4.0 with and without Al treatment. The genes upregulated by low pH were associated mainly with response to oxidative stress, cell wall organization, and iron ion binding. Among genes upregulated by Al, overrepresented were those related to response to stress condition and calcium ion binding. In the long-term experiment, the number of DEGs between hydroponics at pH = 4.0 and 6.0 were lower than in the short-term experiment, which suggests that plants partially adapted to the low pH. Interestingly, 7 days Al treatment caused massive changes in the transcriptome profile. Over 4,000 genes were upregulated and almost 2,000 genes were downregulated by long-term Al stress. These DEGs were related to stress response, cell wall development and metal ion transport. Based on our results we can assume that both, Al3+ ions and low pH are harmful to barley plants. Additionally, we phenotyped the root system of barley seedlings grown in the same hydroponic conditions for 7 days at pH = 6.0, pH = 4.0, and pH = 4.0 with Al. The results correspond to transcriptomic data and show that low pH itself is a stress factor that causes a significant reduction of root growth and the addition of aluminum further increases this reduction. It should be noted that in acidic arable lands, plants are exposed simultaneously to both of these stresses. The presented transcriptome analysis may help to find potential targets for breeding barley plants that are more tolerant to such conditions.

Arabidopsis casein kinase 2 triggers stem cell exhaustion under Al toxicity and phosphate deficiency through activating the DNA damage response pathway.

Aluminum (Al) toxicity and inorganic phosphate (Pi) limitation are widespread chronic abiotic and mutually enhancing stresses that profoundly affect crop yield. Both stresses strongly inhibit root growth, resulting from a progressive exhaustion of the stem cell niche. Here, we report on a casein kinase 2 (CK2) inhibitor identified by its capability to maintain a functional root stem cell niche in Arabidopsis thaliana under Al toxic conditions. CK2 operates through phosphorylation of the cell cycle checkpoint activator SUPPRESSOR OF GAMMA RADIATION1 (SOG1), priming its activity under DNA-damaging conditions. In addition to yielding Al tolerance, CK2 and SOG1 inactivation prevents meristem exhaustion under Pi starvation, revealing the existence of a low Pi-induced cell cycle checkpoint that depends on the DNA damage activator ATAXIA-TELANGIECTASIA MUTATED (ATM). Overall, our data reveal an important physiological role for the plant DNA damage response pathway under agriculturally limiting growth conditions, opening new avenues to cope with Pi limitation.

Al-Tolerant Barley Mutant hvatr.g Shows the ATR-Regulated DNA Damage Response to Maleic Acid Hydrazide.

ATR, a DNA damage signaling kinase, is required for cell cycle checkpoint regulation and detecting DNA damage caused by genotoxic factors including Al3+ ions. We analyzed the function of the HvATR gene in response to chemical clastogen-maleic acid hydrazide (MH). For this purpose, the Al-tolerant barley TILLING mutant hvatr.g was used. We described the effects of MH on the nuclear genome of hvatr.g mutant and its WT parent cv. "Sebastian", showing that the genotoxic effect measured by TUNEL test and frequency of cells with micronuclei was much stronger in hvatr.g than in WT. MH caused a significant decrease in the mitotic activity of root cells in both genotypes, however this effect was significantly stronger in "Sebastian". The impact of MH on the roots cell cycle, analyzed using flow cytometry, showed no differences between the mutant and WT.

A multi-level response to DNA damage induced by aluminium.

Aluminium (Al) ions are one of the primary growth-limiting factors for plants on acid soils, globally restricting agriculture. Despite its impact, little is known about Al action in planta. Earlier work has indicated that, among other effects, Al induces DNA damage. However, the loss of major DNA damage response regulators, such SOG1, partially suppressed the growth reduction in plants seen on Al-containing media. This raised the question whether Al actually causes DNA damage and, if so, how. Here, we provide cytological and genetic data corroborating that exposure to Al leads to DNA double-strand breaks. We find that the Al-induced damage specifically involves homology-dependent (HR) recombination repair. Using an Al toxicity assay that delivers higher Al concentrations than used in previous tests, we find that sog1 mutants become highly sensitive to Al. This indicates a multi-level response to Al-induced DNA damage in plants.

Friedreich's Ataxia: Clinical Presentation of a Compound Heterozygote Child with a Rare Nonsense Mutation and Comparison with Previously Published Cases.

Friedreich's ataxia is a neurodegenerative disorder associated with a GAA trinucleotide repeat expansion in intron 1 of the frataxin (FXN) gene. It is the most common autosomal recessive cerebellar ataxia, with a mean age of onset at 16 years. Nearly 95-98% of patients are homozygous for a 90-1300 GAA repeat expansion with only 2-5% demonstrating compound heterozygosity. Compound heterozygous individuals have a repeat expansion in one allele and a point mutation/deletion/insertion in the other. Compound heterozygosity and point mutations are very rare causes of Friedreich's ataxia and nonsense mutations are a further rarity among point mutations. We report a rare compound heterozygous Friedrich's ataxia patient who was found to have one expanded GAA FXN allele and a nonsense point mutation in the other. We summarize the four previously published cases of nonsense mutations and compare the phenotype to that of our patient. We compared clinical information from our patient with other nonsense FXN mutations reported in the literature. This nonsense mutation, to our knowledge, has only been described once previously; interestingly the individual was also of Cuban ancestry. A comparison with previously published cases of nonsense mutations demonstrates some common clinical characteristics.

A Next-Generation TRK Kinase Inhibitor Overcomes Acquired Resistance to Prior TRK Kinase Inhibition in Patients with TRK Fusion-Positive Solid Tumors.

Larotrectinib, a selective TRK tyrosine kinase inhibitor (TKI), has demonstrated histology-agnostic efficacy in patients with TRK fusion-positive cancers. Although responses to TRK inhibition can be dramatic and durable, duration of response may eventually be limited by acquired resistance. LOXO-195 is a selective TRK TKI designed to overcome acquired resistance mediated by recurrent kinase domain (solvent front and xDFG) mutations identified in multiple patients who have developed resistance to TRK TKIs. Activity against these acquired mutations was confirmed in enzyme and cell-based assays and in vivo tumor models. As clinical proof of concept, the first 2 patients with TRK fusion-positive cancers who developed acquired resistance mutations on larotrectinib were treated with LOXO-195 on a first-in-human basis, utilizing rapid dose titration guided by pharmacokinetic assessments. This approach led to rapid tumor responses and extended the overall duration of disease control achieved with TRK inhibition in both patients.Significance: LOXO-195 abrogated resistance in TRK fusion-positive cancers that acquired kinase domain mutations, a shared liability with all existing TRK TKIs. This establishes a role for sequential treatment by demonstrating continued TRK dependence and validates a paradigm for the accelerated development of next-generation inhibitors against validated oncogenic targets. Cancer Discov; 7(9); 963-72. ©2017 AACR.See related commentary by Parikh and Corcoran, p. 934This article is highlighted in the In This Issue feature, p. 920.

SUV2, which encodes an ATR-related cell cycle checkpoint and putative plant ATRIP, is required for aluminium-dependent root growth inhibition in Arabidopsis.

A suppressor mutagenesis screen was conducted in order to identify second site mutations that could reverse the extreme hypersensitivity to aluminium (Al) seen for the Arabidopsis mutant, als3-1. From this screen, it was found that a loss-of-function mutation in the previously described SUV2 (SENSITIVE TO UV 2), which encodes a putative plant ATRIP homologue that is a component of the ATR-dependent cell checkpoint response, reversed the als3-1 phenotype. This included prevention of hallmarks associated with als3-1 including Al-dependent terminal differentiation of the root tip and transition to endoreduplication. From this analysis, SUV2 was determined to be required for halting cell cycle progression and triggering loss of the quiescent centre (QC) following exposure to Al. In conjunction with this, SUV2 was found to have a similar role as ATR, ALT2 and SOG1 in Al-dependent stoppage of root growth, all of which are required for promotion of expression of a suite of genes that likely are part of an Al-dependent DNA damage transcriptional response. This work argues that these Al response factors work together to detect Al-dependent damage and subsequently activate a DNA damage response pathway that halts the cell cycle and subsequently promotes QC differentiation and entrance into endocycling.

Modification of DNA Checkpoints to Confer Aluminum Tolerance.

Although aluminum (Al) toxicity represents a global agricultural problem, the biochemical targets for Al remain elusive. Recently identified Arabidopsis mutants with increased Al tolerance provide evidence of DNA as one of the main targets of Al. This insight could lead the way for novel strategies to generate Al-tolerant crop plants.

Occipital Bony Abnormality and Multiple Strokes in a Pediatric Patient: Case Report and Review of the Current Literature.

This study presents a case of a 15-year-old boy who had a right vertebral artery dissection with distal embolization from repeated trauma from an occipital bony spicule. The authors hypothesize that this bony spicule was contacting the left vertebral artery during head rotation, resulting in trauma to the vessel and formation of emboli which then showered distally, causing strokes in the posterior circulation of the brain. This specific phenomenon has previously been reported three times, only one of which was in pediatric literature. It is important for individuals to be aware of this rare anatomic cause of vertebral artery dissection in patients presenting with an odd constellation of symptoms related to strokes from vertebro-basilar system. Treatment options including early intervention with intravascular coil embolization are also discussed.

Mechanisms of ethylene biosynthesis and response in plants.

Ethylene is the simplest unsaturated hydrocarbon, yet it has profound effects on plant growth and development, including many agriculturally important phenomena. Analysis of the mechanisms underlying ethylene biosynthesis and signalling have resulted in the elucidation of multistep mechanisms which at first glance appear simple, but in fact represent several levels of control to tightly regulate the level of production and response. Ethylene biosynthesis represents a two-step process that is regulated at both the transcriptional and post-translational levels, thus enabling plants to control the amount of ethylene produced with regard to promotion of responses such as climacteric flower senescence and fruit ripening. Ethylene production subsequently results in activation of the ethylene response, as ethylene accumulation will trigger the ethylene signalling pathway to activate ethylene-dependent transcription for promotion of the response and for resetting the pathway. A more detailed knowledge of the mechanisms underlying biosynthesis and the ethylene response will ultimately enable new approaches to be developed for control of the initiation and progression of ethylene-dependent developmental processes, many of which are of horticultural significance.

Aluminum-Dependent Terminal Differentiation of the Arabidopsis Root Tip Is Mediated through an ATR-, ALT2-, and SOG1-Regulated Transcriptional Response.

By screening for suppressors of the aluminum (Al) hypersensitive Arabidopsis thaliana mutant als3-1, it was found that mutational loss of the Arabidopsis DNA damage response transcription factor SUPPRESSOR OF GAMMA RESPONSE1 (SOG1) confers increased Al tolerance similar to the loss-of-function mutants for the cell cycle checkpoint genes ATAXIA TELANGIECTASIA AND RAD3 RELATED (ATR) and ALUMINUM TOLERANT2 (ALT2). This suggests that Al-dependent terminal differentiation of the root tip is an active process resulting from activation of the DNA damage checkpoint by an ATR-regulated pathway, which functions at least in part through SOG1. Consistent with this, ATR can phosphorylate SOG1 in vitro. Analysis of SOG1's role in Al-dependent root growth inhibition shows that sog1-7 prevents Al-dependent quiescent center differentiation and endoreduplication in the primary root tip. Following Al exposure, SOG1 increases expression of several genes previously associated with DNA damage, including BRCA1 and PARP2, with gel-shift analysis showing that SOG1 can physically associate with the BRCA1 promoter in vitro. Al-responsive expression of these SOG1-regulated genes requires ATR and ALT2, but not ATAXIA TELANGIECTASIA MUTATED, thus demonstrating that in response to chronic Al exposure, ATR, ALT2, and SOG1 function together to halt root growth and promote terminal differentiation at least in part in a transcription-dependent manner.

Team-based Care for Patients Hospitalized with Heart Failure.

Hospitalizations for acute heart failure (HF) and subsequent readmissions have received increased attention because of the burden they place on patients, providers, and the health care system. These hospitalizations represent a significant portion of the total cost of HF care and health care in general. Although much of the care of the patient with HF occurs outside of the hospital, the genesis of the programs that attempt to limit repeat hospitalizations begin in the impatient setting. By using evidence-based guidelines, interdisciplinary teams, and comprehensive discharge planning, costly readmissions can be reduced and outcomes improved.

Dominant gain-of-function mutations in transmembrane domain III of ERS1 and ETR1 suggest a novel role for this domain in regulating the magnitude of ethylene response in Arabidopsis.

Prior work resulted in identification of an Arabidopsis mutant, eer5-1, with extreme ethylene response in conjunction with failure to induce a subset of ethylene-responsive genes, including AtEBP. EER5, which is a TREX-2 homolog that is part of a nucleoporin complex, functions as part of a cryptic aspect of the ethylene signaling pathway that is required for regulating the magnitude of ethylene response. A suppressor mutagenesis screen was carried out to identify second site mutations that could restore the growth of ethylene-treated eer5-1 to wild-type levels. A dominant gain-of-function mutation in the ethylene receptor ETHYLENE RESPONSE SENSOR 1 (ERS1) was identified, with the ers1-4 mutation being located in transmembrane domain III at a point nearly equivalent to the previously described etr1-2 mutation in the other Arabidopsis subfamily I ethylene receptor, ETHYLENE RESPONSE 1 (ETR1). Although both ers1-4 and etr1-2 partially suppress the ethylene hypersensitivity of eer5-1 and are at least in part REVERSION TO ETHYLENE SENSITIVITY 1 (RTE1)-dependent, ers1-4 was additionally found to restore the expression of AtEBP in ers1-4;eer5-1 etiolated seedlings after ethylene treatment in an EIN3-dependent manner. Our work indicates that ERS1-regulated expression of a subset of ethylene-responsive genes is related to controlling the magnitude of ethylene response, with hyperinduction of these genes correlated with reduced ethylene-dependent growth inhibition.

Ophthalmoscopy using an eye simulator model.

BACKGROUND: Ophthalmoscopy is an important skill for the medical student to master. Students have difficulty visualising the retina, and are hesitant to practise with patients. Our study aim was to demonstrate that an eye simulation experience would be beneficial for developing ophthalmoscopy skills. DESIGN: This study was designed for second-year medical students who elected to participate. Students were observed and instructed on the correct use of the ophthalmoscope. Both normal and pathological retinas were used. The students matched what they observed with printed photographs to verify what they had actually seen. A pre- and post-session questionnaire, with comments, was completed. The study was conducted over 4 years. Three of the years were structured as outlined above. One year, the students used the simulator but without an instructor being present. Students were surveyed as senior medical students and asked to rate the value of the simulator experience for preparing them for their clinical years. RESULTS: A total of 64 per cent of the students elected to participate when a faculty member was present to instruct them, whereas only 12 per cent of the class elected for the experience without instruction. The self-rating results from the pre- versus post-session questionnaire showed statistically significant improvement for all items. Student comments reflected that they felt strongly that the experience was valuable to them. CONCLUSIONS: This simulation ophthalmoscopy experience was valuable for increasing confidence and skill. This experience is most valued when an instructor is present. The simulator experience was valuable to students as they applied their ophthalmoscopy skills clinically.

Diverse presentation of breath holding spells: two case reports with literature review.

Breath holding spells are a common and dramatic form of syncope and anoxic seizure in infancy. They are usually triggered by an emotional stimuli or minor trauma. Based on the color change, they are classified into 3 types, cyanotic, pallid, and mixed. Pallid breath holding spells result from exaggerated, vagally-mediated cardiac inhibition, whereas the more common, cyanotic breathholding spells are of more complex pathogenesis which is not completely understood. A detailed and accurate history is the mainstay of diagnosis. An EKG should be strongly considered to rule out long QT syndrome. Spontaneous resolution of breath-holding spells is usually seen, without any adverse developmental and intellectual sequelae. Rare cases of status epilepticus, prolonged asystole, and sudden death have been reported. Reassurance and education is the mainstay of therapy. Occasionally, pharmacologic intervention with iron, piracetam; atropine may be of benefit. Here we present 2 cases, one of each, pallid and cyanotic breath holding spells.

Choking at night: a case of opercular nocturnal frontal lobe epilepsy.

Frontal lobe seizures have a tendency to occur in sleep and in most cases occur exclusively in sleep; these individuals are said to have nocturnal frontal lobe (NFLE). NFLE can be difficult to distinguish clinically from various other sleep disorders, particularly parasomnias, which also present with paroxysmal motor activity in sleep. Interictal and ictal EEG findings are frequently unremarkable or nonspecific in both parasomnias and NFLE making the diagnosis even more difficult. Nocturnal epilepsy should be suspected in patients with paroxysmal events at night characterized by high frequency, repetition, extrapyramidal features, and marked stereotypy of attacks. Here we present a 13-year-old female who was extensively worked up for choking episodes at night. On repeat video EEG she was found to have frontal opercular seizures. Once on Carbamazepine, her seizures completely resolved.

The Arabidopsis cell cycle checkpoint regulators TANMEI/ALT2 and ATR mediate the active process of aluminum-dependent root growth inhibition.

Aluminum (Al) toxicity is a global issue that severely limits root growth in acidic soils. Isolation of suppressors of the Arabidopsis thaliana Al-hypersensitive mutant, als3-1, resulted in identification of a cell cycle checkpoint factor, ALUMINUM TOLERANT2 (ALT2), which monitors and responds to DNA damage. ALT2 is required for active stoppage of root growth after Al exposure, because alt2 loss-of-function mutants fail to halt root growth after Al exposure, do not accumulate CyclinB1;1 in the root tip, and fail to force differentiation of the quiescent center. Thus, alt2-1 mutants are highly tolerant of Al levels that are severely inhibitory to the wild type. The alt2-1 allele is a loss-of-function mutation in a protein containing a putative DDB1-binding WD40 motif, previously identified as TANMEI, which is required for assessment of DNA integrity, including monitoring of DNA crosslinks. alt2-1 and atr loss-of-function mutants, the latter of which affects the cell cycle checkpoint ATAXIA TELANGIECTASIA-MUTATED AND RAD3-RELATED, are severely sensitive to DNA crosslinking agents and have increased Al tolerance. These results suggest that Al likely acts as a DNA-damaging agent in vivo and that Al-dependent root growth inhibition, in part, arises from detection of and response to this damage by TANMEI/ALT2 and ATR, both of which actively halt cell cycle progression and force differentiation of the quiescent center.

A loss-of-function mutation in the nucleoporin AtNUP160 indicates that normal auxin signalling is required for a proper ethylene response in Arabidopsis.

As part of a continuing effort to elucidate mechanisms that regulate the magnitude of ethylene signalling, an Arabidopsis mutant with an enhanced ethylene response was identified. Subsequent characterization of this loss-of-function mutant revealed severe hypocotyl shortening in the presence of saturating ethylene along with increased expression in leaves of a subset of ethylene-responsive genes. It was subsequently determined by map-based cloning that the mutant (sar1-7) represents a loss-of-function mutation in the previously described nucleoporin AtNUP160 (At1g33410, SAR1). In support of previously reported results, the sar1-7 mutant partially restored auxin responsiveness to roots of an rce1 loss-of-function mutant, indicating that AtNUP160/SAR1 is required for proper expression of factors responsible for the repression of auxin signalling. Analysis of arf7-1/sar1-7 and arf19-1/sar1-7 double mutants revealed that mutations affecting either ARF7 or ARF19 function almost fully blocked manifestation of the sar1-7-dependent ethylene hypersensitivity phenotype, suggesting that ARF7- and ARF19-mediated auxin signalling is responsible for regulating the magnitude of and/or competence for the ethylene response in Arabidopsis etiolated hypocotyls. Consistent with this, addition of auxin to ethylene-treated seedlings resulted in severe hypocotyl shortening, reminiscent of that seen for other eer (enhanced ethylene response) mutants, suggesting that auxin functions in part synergistically with ethylene to control hypocotyl elongation and other ethylene-dependent phenomena.