Targeted protein S-nitrosylation of ACE2 inhibits SARS-CoV-2 infection.

Prevention of infection and propagation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a high priority in the Coronavirus Disease 2019 (COVID-19) pandemic. Here we describe S-nitrosylation of multiple proteins involved in SARS-CoV-2 infection, including angiotensin-converting enzyme 2 (ACE2), the receptor for viral entry. This reaction prevents binding of ACE2 to the SARS-CoV-2 spike protein, thereby inhibiting viral entry, infectivity and cytotoxicity. Aminoadamantane compounds also inhibit coronavirus ion channels formed by envelope (E) protein. Accordingly, we developed dual-mechanism aminoadamantane nitrate compounds that inhibit viral entry and, thus, the spread of infection by S-nitrosylating ACE2 via targeted delivery of the drug after E protein channel blockade. These non-toxic compounds are active in vitro and in vivo in the Syrian hamster COVID-19 model and, thus, provide a novel avenue to pursue therapy.

Neuroendocrine tumor of the ampulla of Vater. Review of the literature.

Neuroendocrine tumors (NETs) or carcinoids represent a small percentage of gastrointestinal neoplasms (2%). The ileum (41.8%), rectum (27.4%) and stomach (8.7%) are the most common locations. We present an unusual case of NET due to its origin in the ampulla of Vater, as an extremely rare cause of biliary obstruction. A bibliographic review of the current recommendations of management and treatment for this case, different from other locations of the gastrointestinal tract is carried out. The curative treatment of choice for early-stage Vater ampulla NETs is Whipple surgery with lymphadenectomy due to Its high rate of lymphatic and metastatic dissemination, regardless of size and histological grade, although there are no updated official guidelines.

α-Synuclein Oligomers Induce Glutamate Release from Astrocytes and Excessive Extrasynaptic NMDAR Activity in Neurons, Thus Contributing to Synapse Loss.

Synaptic and neuronal loss are major neuropathological characteristics of Parkinson's disease. Misfolded protein aggregates in the form of Lewy bodies, comprised mainly of α-synuclein (αSyn), are associated with disease progression, and have also been linked to other neurodegenerative diseases, including Lewy body dementia, Alzheimer's disease, and frontotemporal dementia. However, the effects of αSyn and its mechanism of synaptic damage remain incompletely understood. Here, we show that αSyn oligomers induce Ca2+-dependent release of glutamate from astrocytes obtained from male and female mice, and that mice overexpressing αSyn manifest increased tonic release of glutamate in vivo In turn, this extracellular glutamate activates glutamate receptors, including extrasynaptic NMDARs (eNMDARs), on neurons both in culture and in hippocampal slices of αSyn-overexpressing mice. Additionally, in patch-clamp recording from outside-out patches, we found that oligomerized αSyn can directly activate eNMDARs. In organotypic slices, oligomeric αSyn induces eNMDAR-mediated synaptic loss, which can be reversed by the drug NitroSynapsin. When we expose human induced pluripotent stem cell-derived cerebrocortical neurons to αSyn, we find similar effects. Importantly, the improved NMDAR antagonist NitroSynapsin, which selectively inhibits extrasynaptic over physiological synaptic NMDAR activity, protects synapses from oligomeric αSyn-induced damage in our model systems, thus meriting further study for its therapeutic potential.SIGNIFICANCE STATEMENT Loss of synaptic function and ensuing neuronal loss are associated with disease progression in Parkinson's disease (PD), Lewy body dementia (LBD), and other neurodegenerative diseases. However, the mechanism of synaptic damage remains incompletely understood. α-Synuclein (αSyn) misfolds in PD/LBD, forming Lewy bodies and contributing to disease pathogenesis. Here, we found that misfolded/oligomeric αSyn releases excessive astrocytic glutamate, in turn activating neuronal extrasynaptic NMDA receptors (eNMDARs), thereby contributing to synaptic damage. Additionally, αSyn oligomers directly activate eNMDARs, further contributing to damage. While the FDA-approved drug memantine has been reported to offer some benefit in PD/LBD (Hershey and Coleman-Jackson, 2019), we find that the improved eNMDAR antagonist NitroSynapsin ameliorates αSyn-induced synaptic spine loss, providing potential disease-modifying intervention in PD/LBD.

Early work activities after sedation with propofol in digestive endoscopy. Reply.

We read with interest the letter by Dr. Cerezo-Ruiz and we agree in general with the commentaries and would like to add some information related to the use of propofol in deep sedation by our group.

Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial.

AIMS: The Hygia Chronotherapy Trial, conducted within the clinical primary care setting, was designed to test whether bedtime in comparison to usual upon awakening hypertension therapy exerts better cardiovascular disease (CVD) risk reduction. METHODS AND RESULTS: In this multicentre, controlled, prospective endpoint trial, 19 084 hypertensive patients (10 614 men/8470 women, 60.5 ± 13.7 years of age) were assigned (1:1) to ingest the entire daily dose of ≥1 hypertension medications at bedtime (n = 9552) or all of them upon awakening (n = 9532). At inclusion and at every scheduled clinic visit (at least annually) throughout follow-up, ambulatory blood pressure (ABP) monitoring was performed for 48 h. During the 6.3-year median patient follow-up, 1752 participants experienced the primary CVD outcome (CVD death, myocardial infarction, coronary revascularization, heart failure, or stroke). Patients of the bedtime, compared with the upon-waking, treatment-time regimen showed significantly lower hazard ratio-adjusted for significant influential characteristics of age, sex, type 2 diabetes, chronic kidney disease, smoking, HDL cholesterol, asleep systolic blood pressure (BP) mean, sleep-time relative systolic BP decline, and previous CVD event-of the primary CVD outcome [0.55 (95% CI 0.50-0.61), P < 0.001] and each of its single components (P < 0.001 in all cases), i.e. CVD death [0.44 (0.34-0.56)], myocardial infarction [0.66 (0.52-0.84)], coronary revascularization [0.60 (0.47-0.75)], heart failure [0.58 (0.49-0.70)], and stroke [0.51 (0.41-0.63)]. CONCLUSION: Routine ingestion by hypertensive patients of ≥1 prescribed BP-lowering medications at bedtime, as opposed to upon waking, results in improved ABP control (significantly enhanced decrease in asleep BP and increased sleep-time relative BP decline, i.e. BP dipping) and, most importantly, markedly diminished occurrence of major CVD events. TRIAL REGISTRATION: ClinicalTrials.gov, number NCT00741585.

Caveolin-1 Expression in the Dorsal Striatum Drives Methamphetamine Addiction-Like Behavior.

Dopamine D1 receptor (D1R) function is regulated by membrane/lipid raft-resident protein caveolin-1 (Cav1). We examined whether altered expression of Cav1 in the dorsal striatum would affect self-administration of methamphetamine, an indirect agonist at the D1Rs. A lentiviral construct expressing Cav1 (LV-Cav1) or containing a short hairpin RNA against Cav1 (LV-shCav1) was used to overexpress or knock down Cav1 expression respectively, in the dorsal striatum. Under a fixed-ratio schedule, LV-Cav1 enhanced and LV-shCav1 reduced responding for methamphetamine in an extended access paradigm compared to LV-GFP controls. LV-Cav1 and LV-shCav1 also produced an upward and downward shift in a dose-response paradigm, generating a drug vulnerable/resistant phenotype. LV-Cav1 and LV-shCav1 did not alter responding for sucrose. Under a progressive-ratio schedule, LV-shCav1 generally reduced positive-reinforcing effects of methamphetamine and sucrose as seen by reduced breakpoints. Western blotting confirmed enhanced Cav1 expression in LV-Cav1 rats and reduced Cav1 expression in LV-shCav1 rats. Electrophysiological findings in LV-GFP rats demonstrated an absence of high-frequency stimulation (HFS)-induced long-term potentiation (LTP) in the dorsal striatum after extended access methamphetamine self-administration, indicating methamphetamine-induced occlusion of plasticity. LV-Cav1 prevented methamphetamine-induced plasticity via increasing phosphorylation of calcium calmodulin kinase II, suggesting a mechanism for addiction vulnerability. LV-shCav1 produced a marked deficit in the ability of HFS to produce LTP and, therefore, extended access methamphetamine was unable to alter striatal plasticity, indicating a mechanism for resistance to addiction-like behavior. Our results demonstrate that Cav1 expression and knockdown driven striatal plasticity assist with modulating addiction to drug and nondrug rewards, and inspire new strategies to reduce psychostimulant addiction.

Balanced by iron. Hereditary hemochromatosis and celiac disease.

We present the case of a healthy 14-year-old adolescent who was referred to our hospital for an incidental alteration of the iron profile (Fe 225 ug/dl, transferrin 186 mg/dl, IST 63.93 %, ferritin 253 ng/ml). The blood count, proteinogram and renal, lipid and liver function tests were in the normal range. Abdominal ultrasound was requested with no findings of interest. The genetic analysis for hereditary hemochromatosis (HH) confirmed that the patient was homozygous for the C282Y mutation.

Acute hepatocellular drug-induced liver injury probably caused by doxazosin.

Drug-induced liver injury (DILI) is a diagnostic challenge, due to the hepatotoxic potential of drugs, herbs and dietary supplements, the variety of pathological phenotypes and the absence of specific biomarkers.

MEF2D haploinsufficiency downregulates the NRF2 pathway and renders photoreceptors susceptible to light-induced oxidative stress.

Gaining mechanistic insight into interaction between causative factors of complex multifactorial diseases involving photoreceptor damage might aid in devising effective therapies. Oxidative stress is one of the potential unifying mechanisms for interplay between genetic and environmental factors that contribute to photoreceptor pathology. Interestingly, the transcription factor myocyte enhancer factor 2d (MEF2D) is known to be important in photoreceptor survival, as knockout of this transcription factor results in loss of photoreceptors in mice. Here, using a mild light-induced retinal degeneration model, we show that the diminished MEF2D transcriptional activity in Mef2d+/- retina is further reduced under photostimulation-induced oxidative stress. Reactive oxygen species cause an aberrant redox modification on MEF2D, consequently inhibiting transcription of its downstream target, nuclear factor (erythroid-derived 2)-like 2 (NRF2). NRF2 is a master regulator of phase II antiinflammatory and antioxidant gene expression. In the Mef2d heterozygous mouse retina, NRF2 is not up-regulated to a normal degree in the face of light-induced oxidative stress, contributing to accelerated photoreceptor cell death. Furthermore, to combat this injury, we found that activation of the endogenous NRF2 pathway using proelectrophilic drugs rescues photoreceptors from photo-induced oxidative stress and may therefore represent a viable treatment for oxidative stress-induced photoreceptor degeneration, which is thought to contribute to some forms of retinitis pigmentosa and age-related macular degeneration.

Does Timing of Antihypertensive Medication Dosing Matter?

PURPOSE OF REVIEW: Current hypertension guidelines do not provide recommendation on when-to-treat. Herein, we review the current evidence on ingestion-time differences of hypertension medications in blood pressure (BP)-lowering effects and prevention of cardiovascular disease (CVD) events. RECENT FINDINGS: The vast (81.6%) majority of the 136 published short-term treatment-time trials document benefits, including enhanced reduction of asleep BP and increased sleep-time relative BP decline (dipping), when hypertension medications and their combinations are ingested before sleep rather than upon waking. Long-term outcome trials further document bedtime hypertension therapy markedly reduces risk of major CVD events. The inability of the very small 18.4% of the published trials to substantiate treatment-time difference in effects is mostly explained by deficiencies of study design and conduct. Our comprehensive review of the published literature reveals no single study has reported better benefits of the still conventional, yet scientifically unjustified, morning than bedtime hypertension treatment scheme.

SCH23390 Reduces Methamphetamine Self-Administration and Prevents Methamphetamine-Induced Striatal LTD.

Extended-access methamphetamine self-administration results in unregulated intake of the drug; however, the role of dorsal striatal dopamine D1-like receptors (D1Rs) in the reinforcing properties of methamphetamine under extended-access conditions is unclear. Acute (ex vivo) and chronic (in vivo) methamphetamine exposure induces neuroplastic changes in the dorsal striatum, a critical region implicated in instrumental learning. For example, methamphetamine exposure alters high-frequency stimulation (HFS)-induced long-term depression in the dorsal striatum; however, the effect of methamphetamine on HFS-induced long-term potentiation (LTP) in the dorsal striatum is unknown. In the current study, dorsal striatal infusion of SCH23390, a D1R antagonist, prior to extended-access methamphetamine self-administration reduced methamphetamine addiction-like behavior. Reduced behavior was associated with reduced expression of PSD-95 in the dorsal striatum. Electrophysiological findings demonstrate that superfusion of methamphetamine reduced basal synaptic transmission and HFS-induced LTP in dorsal striatal slices, and SCH23390 prevented this effect. These results suggest that alterations in synaptic transmission and synaptic plasticity induced by acute methamphetamine via D1Rs could assist with methamphetamine-induced modification of corticostriatal circuits underlying the learning of goal-directed instrumental actions and formation of habits, mediating escalation of methamphetamine self-administration and methamphetamine addiction-like behavior.

Problems with a prophylactic non-expulsive pancreatic stent.

We appreciate the advice and comment of Drs. García Cano and Viñuelas about the best plastic stent for the prevention of post-endoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis. We are aware of the benefit of placing a plastic stent in cases where the pancreatic duct is incorrectly and accidentally canalized in an attempt to access the biliary tree, as shown in their original paper.

Acute pancreatitis secondary to a plastic prophylactic pancreatic prosthesis.

Plastic pancreatic prosthesis are indicated in the prophylactic of post-ERCP pancreatitis. But paradoxically, these prosthesis can cause pancreatitis if they are not expelled in a short period of time.

Hemorrhagic complications following paracentesis.

Paracentesis is a common and well accepted technique for its diagnostic-therapeutic profitability. This procedure is considered rapid, minimally invasive and safe, but we must not forget that it can lead to severe complications. In this letter we present two patients with hemorrhagic complications following paracentesis. Both cases were treated by percutaneous transarterial embolization. Likewise, in the absence of consensus on the prevention of complications and on their optimal management, we make some recommendations.

Percutaneous hepatic biopsy under propofol sedation. A safe and effective procedure.

INTRODUCTION: the percutaneous hepatic biopsy is a necessary procedure for the diagnosis of liver diseases which can cause complications and psychological discomfort for the patient. AIMS: to determine the safety profile of propofol in percutaneous hepatic biopsy, the complications of the technique per se and patients satisfaction once completed. METHODS: a retrospective observational study was performed via the acquisition of data of tolerance and perceived quality by the patients using a transversal survey. RESULTS: ninety-seven patients were included with an average propofol dose of 170.46 mg. Of the complications resulting from the sedation, there were six slight desaturations (6.2 %) resolved with a forehead maneuver (50 %) or cessation of the propofol infusion pump (50 %) and eleven hypotension episodes (11.3 %) resolved without intervention (82.82 %) or with fluid replacement (18.18 %). Of the complications resulting from the technique, there were three cases of early-onset pain (3.1 %) and one delayed (1.03 %); all were resolved with 1 g of intravenous paracetamol. All patients were discharged with oral tolerance and without the need for analgesia 24 hours after the procedure. General satisfaction, as well as psychological discomfort, were evaluated as "very good/excellent" in 100 % of the patients. DISCUSSION: propofol demonstrated a favorable safety profile in hepatic biopsy, aiding in the ultimate success of the procedure and tolerance for the patient. We propose the expansion of the use of sedation with propofol to this procedure.

Spanish online survey on informed consent for the performance of paracentesis. Do we have it? Do we use it?

INTRODUCTION: informed consent is necessary for invasive procedures as a document that guarantees the ethical health relationship and patient safety. AIMS: to analyze whether we have and use informed consent documents for paracentesis in our hospitals and to obtain data on the technique. METHODS: a descriptive observational study was performed during December 2019, via a cross-sectional survey disseminated through social networks, aimed at specialists and residents of gastroenterology. RESULTS: two hundred and three anonymous surveys were included (55.2 % gastroenterologist and 44.8 % residents) from 74 hospitals in 34 Spanish provinces. Ninety respondents (44.3 %) stated that they had the document in their centers. Of these, 29 (32.2 %) always provided it, 31 (34.4 %) provided it sometimes and 21 (23.3 %) never. Seventy-two professionals (35.5 %) answered that they did not have it and 41 (20.5 %) selected "unknown". Of these, 77 (68.1 %) considered it was necessary to create this document, 31 (27.4 %) did not think it was necessary and five (4.4 %) did not answer. With regards to the technique, 173 (85.2 %) performed paracentesis under direct visualization and 30 (14.8 %) were eco-guided on most occasions. One hundred and nine (53.7 %) always applied local anesthetic, 80 (39.4 %) sometimes and 14 (6.9 %) did not. One hundred and sixty-seven respondents (82.3 %) considered it to be a simple technique versus 36 (17.7 %) who thought that it was of intermediate complexity. In terms of risk, 150 (73.5 %) considered it was low and 52 (25.6 %), medium. Ninety-nine (48.8 %) experienced minor complications and 37 (18.2 %) experienced major complications. CONCLUSIONS: paracentesis is a common technique in digestive services and could be associated with complications, even though it is considered to be simple and safe. Due to the important intra- and inter-hospital variability that this technique presents, we consider standardized training in this technique is necessary, as well as the creation, spread and use of informed consents.

NitroSynapsin for the treatment of neurological manifestations of tuberous sclerosis complex in a rodent model.

Tuberous sclerosis (TSC) is an autosomal dominant disorder caused by heterozygous mutations in the TSC1 or TSC2 gene. TSC is often associated with neurological, cognitive, and behavioral deficits. TSC patients also express co-morbidity with anxiety and mood disorders. The mechanism of pathogenesis in TSC is not entirely clear, but TSC-related neurological symptoms are accompanied by excessive glutamatergic activity and altered synaptic spine structures. To address whether extrasynaptic (e)NMDA-type glutamate receptor (NMDAR) antagonists, as opposed to antagonists that block physiological phasic synaptic activity, can ameliorate the synaptic and behavioral features of this disease, we utilized the Tsc2+/- mouse model of TSC to measure biochemical, electrophysiological, histological, and behavioral parameters in the mice. We found that antagonists that preferentially block tonic activity as found at eNMDARs, particularly the newer drug NitroSynapsin, provide biological and statistically significant improvement in Tsc2+/- phenotypes. Accompanying this improvement was correction of activity in the p38 MAPK-TSC-Rheb-mTORC1-S6K1 pathway. Deficits in hippocampal long-term potentiation (LTP), histological loss of synapses, and behavioral fear conditioning in Tsc2+/- mice were all improved after treatment with NitroSynapsin. Taken together, these results suggest that amelioration of excessive excitation, by limiting aberrant eNMDAR activity, may represent a novel treatment approach for TSC.

Characterization of triple-negative breast cancer preclinical models provides functional evidence of metastatic progression.

Triple-negative breast cancer (TNBC), an aggressive, metastatic and recurrent breast cancer (BC) subtype, currently suffers from a lack of adequately described spontaneously metastatic preclinical models that faithfully reproduce the clinical scenario. We describe two preclinical spontaneously metastatic TNBC orthotopic murine models for the development of advanced therapeutics: an immunodeficient human MDA-MB-231-Luc model and an immunocompetent mouse 4T1 model. Furthermore, we provide a broad range of multifactorial analysis for both models that could provide relevant information for the development of new therapies and diagnostic tools. Our comparisons uncovered differential growth rates, stromal arrangements and metabolic profiles in primary tumors, and the presence of cancer-associated adipocyte infiltration in the MDA-MB-231-Luc model. Histopathological studies highlighted the more rapid metastatic spread to the lungs in the 4T1 model following a lymphatic route, while we observed both homogeneous (MDA-MB-231-Luc) and heterogeneous (4T1) metastatic spread to axillary lymph nodes. We encountered unique metabolomic signatures in each model, including crucial amino acids and cell membrane components. Hematological analysis demonstrated severe leukemoid and lymphoid reactions in the 4T1 model with the partial reestablishment of immune responses in the immunocompromised MDA-MB-231-Luc model. Additionally, we discovered ß-immunoglobulinemia and increased basal levels of G-CSF correlating with a metastatic switch, with G-CSF also promoting extramedullary hematopoiesis (both models) and causing hepatosplenomegaly (4T1 model). Overall, we believe that the characterization of these preclinical models will foster the development of advanced therapeutic strategies for TNBC treatment, especially for the treatment of patients presenting both, primary tumors and metastatic spread.

Occurrence and genetic diversity of Enterocytozoon bieneusi (Microsporidia) in owned and sheltered dogs and cats in Northern Spain.

Enterocytozoon bieneusi is an obligate intracellular protist-like fungi parasite that infects numerous mammal hosts including humans, raising concerns of zoonotic transmission. There is little information available on the presence and diversity of E. bieneusi genotypes in companion animals. Here, we determined the occurrence and genetic diversity of E. bieneusi in domestic dogs and cats from Northern Spain. A total of 336 genomic DNA samples extracted from canine (n = 237) and feline (n = 99) faecal specimens were retrospectively investigated. The presence of E. bieneusi was assessed by PCR of the rRNA internal transcribed spacer (ITS) gene. The parasite was detected in 3.0% (3/99) and 0.8% (2/237) of the cats and dogs examined, respectively. All three feline positive samples were from stray cats living in an urban setting, whereas the two canine samples were from owned dogs living in rural areas. Sequence analysis revealed the presence of two genotypes in dogs, BEB6 and PtEb IX, and two genotypes in cats, D and Peru11. The identification of Peru11 in a cat and BEB6 in a dog constitutes the first report of those genotypes in such hosts as well as first report in Spain. This is also the first evidence of genotype D in cats and PtEb IX in dogs in Spain. Three out of the four genotypes, BEB6, D and Peru11, have been previously reported as human pathogens and are potentially zoonotic indicating that dogs and cats need to be considered potential sources of human infection and environmental contamination.