Serratia endocarditis, uncommon organism, with significant complications.

Serratia marcescens is an aerobic, Gram-negative bacillus predominantly seen in patients with intravenous drug use, immunosuppression, previous antibiotic exposure, and indwelling catheterization. Gram-negative organism causing infective endocarditis (IE) is rare. Serratia marcescens IE is uncommon and is reported to be seen in 0.14% of all cases. In this report, we discuss in detail about a 38-year-old man with a history of intravenous drug abuse presenting with S. marcescens related prosthetic valve IE.

Identification and characterization of long non-coding RNA and their response against citrus bark cracking viroid infection in Humulus lupulus.

Long non-coding RNAs (lncRNAs) are a highly heterogeneous class of non-protein-encoding transcripts that play an essential regulatory role in diverse biological processes, including stress responses. The severe stunting disease caused by Citrus bark cracking viroid (CBCVd) poses a major threat to the production of Humulus lupulus (hop) plants. In this study, we systematically investigate the characteristics of the lncRNAs in hop and their role in CBCVd-infection using RNA-sequencing data. Following a stringent filtration criterion, a total of 3598 putative lncRNAs were identified with a high degree of certainty, of which 19% (684) of the lncRNAs were significantly differentially expressed (DE) in CBCVd-infected hop, which were predicted to be mainly involved in plant-pathogen interactions, kinase cascades, secondary metabolism and phytohormone signal transduction. Besides, several lncRNAs and CBCVd-responsive lncRNAs were identified as the precursor of microRNAs and predicted as endogenous target mimics (eTMs) for hop microRNAs involved in CBCVd-infection.

Discovery of microRNA-like Small RNAs in Pathogenic Plant Fungus Verticillium nonalfalfae Using High-Throughput Sequencing and qPCR and RLM-RACE Validation.

Verticillium nonalfalfae (V. nonalfalfae) is one of the most problematic hop (Humulus lupulus L.) pathogens, as the highly virulent fungal pathotypes cause severe annual yield losses due to infections of entire hop fields. In recent years, the RNA interference (RNAi) mechanism has become one of the main areas of focus in plant-fungal pathogen interaction studies and has been implicated as one of the major contributors to fungal pathogenicity. MicroRNA-like RNAs (milRNAs) have been identified in several important plant pathogenic fungi; however, to date, no milRNA has been reported in the V. nonalfalfae species. In the present study, using a high-throughput sequencing approach and extensive bioinformatics analysis, a total of 156 milRNA precursors were identified in the annotated V. nonalfalfae genome, and 27 of these milRNA precursors were selected as true milRNA candidates, with appropriate microRNA hairpin secondary structures. The stem-loop RT-qPCR assay was used for milRNA validation; a total of nine V. nonalfalfae milRNAs were detected, and their expression was confirmed. The milRNA expression patterns, determined by the absolute quantification approach, imply that milRNAs play an important role in the pathogenicity of highly virulent V. nonalfalfae pathotypes. Computational analysis predicted milRNA targets in the V. nonalfalfae genome and in the host hop transcriptome, and the activity of milRNA-mediated RNAi target cleavage was subsequently confirmed for two selected endogenous fungal target gene models using the 5' RLM-RACE approach.

The Genome of the Mimosoid Legume Prosopis cineraria, a Desert Tree.

The mimosoid legumes are a clade of ~40 genera in the Caesalpinioideae subfamily of the Fabaceae that grow in tropical and subtropical regions. Unlike the better studied Papilionoideae, there are few genomic resources within this legume group. The tree Prosopis cineraria is native to the Near East and Indian subcontinent, where it thrives in very hot desert environments. To develop a tool to better understand desert plant adaptation mechanisms, we sequenced the P. cineraria genome to near-chromosomal assembly, with a total sequence length of ~691 Mb. We predicted 77,579 gene models (76,554 CDS, 361 rRNAs and 664 tRNAs) from the assembled genome, among them 55,325 (~72%) protein-coding genes that were functionally annotated. This genome was found to consist of over 58% repeat sequences, primarily long terminal repeats (LTR-)-retrotransposons. We find an expansion of terpenoid metabolism genes in P. cineraria and its relative Prosopis alba, but not in other legumes. We also observed an amplification of NBS-LRR disease-resistance genes correlated with LTR-associated retrotransposition, and identified 410 retrogenes with an active burst of chimeric retrogene creation that approximately occurred at the same time of divergence of P. cineraria from a common lineage with P. alba~23 Mya. These retrogenes include many biotic defense responses and abiotic stress stimulus responses, as well as the early Nodulin 93 gene. Nodulin 93 gene amplification is consistent with an adaptive response of the species to the low nitrogen in arid desert soil. Consistent with these results, our differentially expressed genes show a tissue specific expression of isoprenoid pathways in shoots, but not in roots, as well as important genes involved in abiotic salt stress in both tissues. Overall, the genome sequence of P. cineraria enriches our understanding of the genomic mechanisms of its disease resistance and abiotic stress tolerance. Thus, it is a very important step in crop and legume improvement.

Infections precipitating Takotsubo cardiomyopathy, an uncommon complication of a common infection.

Takotsubo cardiomyopathy (TTC) is a non-ischemic cardiomyopathy precipitated by stress. Various infections are reported to precipitate this form of cardiomyopathy. We report a patient presenting with TTC secondary to influenza.  In this article, we also discuss the various infections reported to precipitate this form of reversible cardiomyopathy in literature. We have also included the recent reports of TTC among patients with COVID-19.

Coronavirus disease 2019 and mechanical circulatory support devices: a comprehensive review.

Coronavirus disease (COVID-19) can cause circulatory shock refractory to medical therapy. Such patients can be managed with mechanical circulatory support (MCS) devices like IABP, Impella, VA ECMO, and Left Ventricular Assist Devices (LVADs). Moreover, patients on long-term durable LVADs are a special population having increased susceptibility and mortality to COVID-19 infection. In this narrative review, we searched PubMed and Medline for studies on COVID-19 patients on short-term MCS devices. We found 36 papers with 110 patients who met our review criteria, including 89 LVAD patients and 21 COVID-19 patients who needed MCS device therapy. These studies were used to extract patient demographics, clinical presentation, MCS device details, management, and outcomes. Mean age of patients with COVID-19 infection on LVADs was 60, 73% were male, and HeartMate 3 was the most common device (53%). Most patients (77.5%) needed hospitalization, and mortality was 23.6%. Among the 21 reported cases of critically ill COVID-19 patients who required MCS, the mean age was 49.8 years, 52% were women, and the most common MCS device used was VA ECMO (62%) in conjunction with an Impella for LV venting. Comorbidities were not present in 43%, but 71% had abnormal ventricular function on echocardiography. MCS is a viable option for managing severe COVID-19 infection with shock, with many reported cases of favorable outcomes.

Molecular insights into the role of plant transporters in salt stress response.

Salt stress disturbs the cellular osmotic and ionic balance, which then creates a negative impact on plant growth and development. The Na+ and Cl- ions can enter into plant cells through various membrane transporters, including specific and non-specific Na+ , K+ , and Ca2+ transporters. Therefore, it is important to understand Na+ and K+ transport mechanisms in plants along with the isolation of genes, their characterization, the structural features, and their post-translation regulation under salt stress. This review summarizes the molecular insights of plant ion transporters, including non-selective cation transporters, cyclic nucleotide-gated cation transporters, glutamate-like receptors, membrane intrinsic proteins, cation proton antiporters, and sodium proton antiporter families. Further, we discussed the K+ transporter families such as high-affinity K+ transporters, HAK/KUP/KT transporters, shaker type K+ transporters, and K+ efflux antiporters. Besides the ion transport process, we have shed light on available literature on epigenetic regulation of transport processes under salt stress. Recent advancements of salt stress sensing mechanisms and various salt sensors within signaling transduction pathways are discussed. Further, we have compiled salt-stress signaling pathways, and their crosstalk with phytohormones.

Endocrinological abnormalities and Takotsubo cardiomyopathy.

Dear Editor, We read with much excitement in the article "Takotsubo syndrome and pheochromocytoma: an insidious combination" published by Maffé et al. in your esteemed journal...

Pneumothorax and pneumomediastinum in COVID-19 acute respiratory distress syndrome.

COVID-19 has involved numerous countries across the globe and the disease burden, susceptible age group; mortality rate has been variable depending on the demographical profile, economic status, and health care infrastructure. In the current clinical environment, COVID-19 is one of the most important clinical differential diagnoses in patients presenting with respiratory symptoms. The optimal mechanical ventilation strategy for these patients has been a constant topic of discussion and very importantly so, since a great majority of these patients require invasive mechanical ventilation and often for an extended period of time. In this report we highlight our experience with a COVID-19 patient who most likely suffered barotrauma either as a result of traumatic endotracheal intubation or primarily due to COVID-19 itself. We also aim to highlight the current literature available to suggest the management strategy for these patients for a favorable outcome. The cases described are diverse in terms of age variance and other comorbidities. According to the literature, certain patients, with COVID-19 disease and spontaneous pneumothorax were noted to be managed conservatively and oxygen supplementation with nasal cannula sufficed. Decision regarding need and escalation to invasive mechanical ventilation should be taken early in the disease to avoid complications such as patient self-inflicted lung injury (P-SILI) and barotrauma sequelae such as pneumothorax and pneumomediastinum Recent systematic review further supports the fact that the use of non-invasive ventilation (NIV) in certain patients with COVID-19 pneumonia may give a false sense of security and clinical stabilization but has no overall benefit to avoid intubation. While invasive mechanical ventilation may be associated with higher rates of barotrauma, this should not mean that intubation and invasive mechanical ventilation should be delayed. This becomes an important consideration when non-intensivists or personnel with less experience provide care for this vulnerable patient population who may rely too heavily on NIV to avoid intubation and mechanical ventilation.

Aortic root fistula complicating Austrian syndrome.

Austrian syndrome occurs in 1.2% of all patients with pneumococcal infective endocarditis. It presents with the triad of meningitis, pneumonia, and endocarditis. It is commonly seen in elderly males with a history of alcohol abuse, an immunocompromised state, or recent valve surgery. We present a case of Austrian syndrome presenting with paravalvular complications in the form of aortic root fistula. In this report, we describe the second patient with the community-acquired, pneumococcal, native, aortic valve, endocarditis with Austrian syndrome complicated by the development of an aortic fistula.

Elimination of Viroids from Tobacco Pollen Involves a Decrease in Propagation Rate and an Increase of the Degradation Processes.

Some viroids-single-stranded, non-coding, circular RNA parasites of plants-are not transmissible through pollen to seeds and to next generation. We analyzed the cause for the elimination of apple fruit crinkle viroid (AFCVd) and citrus bark cracking viroid (CBCVd) from male gametophyte cells of Nicotiana tabacum by RNA deep sequencing and molecular methods using infected and transformed tobacco pollen tissues at different developmental stages. AFCVd was not transferable from pollen to seeds in reciprocal pollinations, due to a complete viroid eradication during the last steps of pollen development and fertilization. In pollen, the viroid replication pathway proceeds with detectable replication intermediates, but is dramatically depressed in comparison to leaves. Specific and unspecific viroid degradation with some preference for (-) chains occurred in pollen, as detected by analysis of viroid-derived small RNAs, by quantification of viroid levels and by detection of viroid degradation products forming "comets" on Northern blots. The decrease of viroid levels during pollen development correlated with mRNA accumulation of several RNA-degrading factors, such as AGO5 nuclease, DICER-like and TUDOR S-like nuclease. In addition, the functional status of pollen, as a tissue with high ribosome content, could play a role during suppression of AFCVd replication involving transcription factors IIIA and ribosomal protein L5.

Integrated Proteo-Transcriptomic Analyses Reveal Insights into Regulation of Pollen Development Stages and Dynamics of Cellular Response to Apple Fruit Crinkle Viroid (AFCVd)-Infection in Nicotiana tabacum.

Tobacco (Nicotiana tabacum) pollen is a well-suited model for studying many fundamental biological processes owing to its well-defined and distinct development stages. It is also one of the major agents involved in the transmission of infectious viroids, which is the primary mechanism of viroid pathogenicity in plants. However, some viroids are non-transmissible and may be possibly degraded or eliminated during the gradual process of pollen development maturation. The molecular details behind the response of developing pollen against the apple fruit crinkle viroid (AFCVd) infection and viroid eradication is largely unknown. In this study, we performed an integrative analysis of the transcriptome and proteome profiles to disentangle the molecular cascade of events governing the three pollen development stages: early bicellular pollen (stage 3, S3), late bicellular pollen (stage 5, S5), and 6 h-pollen tube (PT6). The integrated analysis delivered the molecular portraits of the developing pollen against AFCVd infection, including mechanistic insights into the viroid eradication during the last steps of pollen development. The isobaric tags for label-free relative quantification (iTRAQ) with digital gene expression (DGE) experiments led us to reliably identify subsets of 5321, 5286, and 6923 proteins and 64,033, 60,597, and 46,640 expressed genes in S3, S5, and PT6, respectively. In these subsets, 2234, 2108 proteins and 9207 and 14,065 mRNAs were differentially expressed in pairwise comparisons of three stages S5 vs. S3 and PT6 vs. S5 of control pollen in tobacco. Correlation analysis between the abundance of differentially expressed mRNAs (DEGs) and differentially expressed proteins (DEPs) in pairwise comparisons of three stages of pollen revealed numerous discordant changes in mRNA/protein pairs. Only a modest correlation was observed, indicative of divergent transcription, and its regulation and importance of post-transcriptional events in the determination of the fate of early and late pollen development in tobacco. The functional and enrichment analysis of correlated DEGs/DEPs revealed the activation in pathways involved in carbohydrate metabolism, amino acid metabolism, lipid metabolism, and cofactor as well as vitamin metabolism, which points to the importance of these metabolic pathways in pollen development. Furthermore, the detailed picture of AFCVd-infected correlated DEGs/DEPs was obtained in pairwise comparisons of three stages of infected pollen. The AFCVd infection caused the modulation of several genes involved in protein degradation, nuclear transport, phytohormone signaling, defense response, and phosphorylation. Intriguingly, we also identified several factors including, DNA-dependent RNA-polymerase, ribosomal protein, Argonaute (AGO) proteins, nucleotide binding proteins, and RNA exonucleases, which may plausibly involve in viroid stabilization and eradication during the last steps of pollen development. The present study provides essential insights into the transcriptional and translational dynamics of tobacco pollen, which further strengthens our understanding of plant-viroid interactions and support for future mechanistic studies directed at delineating the functional role of candidate factors involved in viroid elimination.

Mapping the Gene Expression Spectrum of Mediator Subunits in Response to Viroid Infection in Plants.

The mediator (MED) represents a large, conserved, multi-subunit protein complex that regulates gene expression through interactions with RNA polymerase II and enhancer-bound transcription factors. Expanding research accomplishments suggest the predominant role of plant MED subunits in the regulation of various physiological and developmental processes, including the biotic stress response against bacterial and fungal pathogens. However, the involvement of MED subunits in virus/viroid pathogenesis remains elusive. In this study, we investigated for the first time the gene expression modulation of selected MED subunits in response to five viroid species (Apple fruit crinkle viroid (AFCVd), Citrus bark cracking viroid (CBCVd), Hop latent viroid (HLVd), Hop stunt viroid (HSVd), and Potato spindle tuber viroid (PSTVd)) in two model plant species (Nicotiana tabacum and N. benthamiana) and a commercially important hop (Humulus lupulus) cultivar. Our results showed a differential expression pattern of MED subunits in response to a viroid infection. The individual plant MED subunits displayed a differential and tailored expression pattern in response to different viroid species, suggesting that the MED expression is viroid- and plant species-dependent. The explicit evidence obtained from our results warrants further investigation into the association of the MED subunit with symptom development. Together, we provide a comprehensive portrait of MED subunit expression in response to viroid infection and a plausible involvement of MED subunits in fine-tuning transcriptional reprogramming in response to viroid infection, suggesting them as a potential candidate for rewiring the defense response network in plants against pathogens.

COVID-19 and clinical mimics. Correct diagnosis is the key to appropriate therapy.

As of 29 April 2020, across the globe, there are 3,216,353 confirmed Coronavirus disease 2019 (COVID-19 disease) with 227,894 deaths. The health care infrastructure of most of the countries is overwhelmed due to the gigantic upsurge of the new cases within a short time period. Most of the beds in the regular wards and critical care units are currently occupied by either people under investigation (PUI) or COVID-19 confirmed cases. We hereby discuss the challenges faced while approaching any case of shortness of breath, or other common upper respiratory symptoms during the current COVID-19 pandemic era.

Gram-negative infective endocarditis: a retrospective analysis of 10 years data on clinical spectrum, risk factor and outcome.

Infective endocarditis (IE) is a significant cause of morbidity and mortality. Underlying congenital heart disease and acquired valvular disease significantly increases the IE risk, which is still prevalent in developing countries. Gram-negative organism related IE prevalence appears to be rising with limited data on their presentation and outcomes. This study hopes to shed further light on this subject. This retrospective cross-sectional study occurred in a tertiary care center in South India. A retrospective cross-sectional study performed in a single tertiary care center in South India. All patients with IE from 2006 to 2016 were included in this study. The details of clinical presentation, laboratory investigations, clinical course, microbiology, and outcomes were obtained. Patients fulfilling the modified Duke's criteria and a culture-proven diagnosis of gram-negative IE were eligible for inclusion. A total of 27 patients were enrolled from Jan 2006 to Dec 2016, among whom 78% were male. Prior structural heart disease was common in our cohort (41%) with renal (55%) and embolic (51%) complications being the most common systemic complications. A comparison of mortality with survivors found that congenital and acquired structural heart disease had a higher risk of mortality. Non-fermenting GNB accounted for 52% of the cohort, with Pseudomonas accounting for 19%. E. coli was the most common bacilli isolated, constituting 37% of the cohort. Assessment of risk factors for adverse outcomes found that renal dysfunction and intravascular device were significant with multivariate-logarithmic analysis showing renal dysfunction as an independent risk factor. In-hospital mortality in this series was 30%. In conclusion, gram-negative IE was more prevalent among males. Underlying structural heart disease was the most common risk factor associated with the disease. Renal dysfunction and embolic complications were the most common complications in this cohort. E. coli and NFGNB accounted for 70% of the offending organisms. In-hospital mortality was similar to patients with IE secondary to common organisms. The presence of renal dysfunction was an independent risk factor for an adverse outcome.

Quantifying and reporting cardiac findings in imaging of COVID-19 patients.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection continues to be a public health emergency and a pandemic of international concern. As of April 31st,  the reported cases of COVID-19 are three million in 186 countries. Reported case fatality has crossed 200 thousand among which more than fifty thousand has been in the USA. Most patients present with symptoms of fever, cough, and shortness of breath following exposure to other COVID-19 patients. Respiratory manifestations predominate in patients with mild, moderate, severe illness. Imaging of patients with COVID-19 consistently reports various pulmonary parenchymal involvement. In this article we wanted to reinforce and review the various reported imaging patterns of cardiac and mediastinal involvement in COVID-19 patients. Among patients with COVID 19 who underwent various imaging of chest various cardiac findings including pericardial effusion, myocarditis, cardiomegaly has been reported. Most of these findings have been consistently reported in patients with significant acute myocardial injury, and fulminant myocarditis. Acute biventricular dysfunction has also been reported with subsequent improvement of the same following clinical improvement. Details of cardiac MRI is rather limited. In a patient with clinical presentation of acute myocarditis, biventricular myocardial interstitial edema, diffuse biventricular hypokinesia, increased ventricular wall thickness, and severe LV dysfunction has been reported. Among patients with significant clinical improvement in LV structure and function has also been documented. With increasing number of clinical cases, future imaging studies will be instrumental in identifying the various cardiac manifestations, and their relation to clinical outcome.

COVID-2019: update on epidemiology, disease spread and management.

With each passing day, more cases of Coronavirus disease (COVID-2019) are being detected and unfortunately the fear of novel corona virus 2019 (2019-nCoV) becoming a pandemic disease has come true. Constant efforts at individual, national, and international level are being made in order to understand the genomics, hosts, modes of transmission and epidemiological link of nCoV-2019. As of now, whole genome sequence of the newly discovered coronavirus has already been decoded. Genomic characterization nCoV-2019 have shown close homology with bat-derived severe acute respiratory syndrome (SARS)-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21. Structural analysis of the receptor binding site has confirmed that 2019-nCoV binds with the same ACE 2 receptor protein as human SARS virus. Compared to the previous coronavirus outbreaks, the overall mortality rate is relatively low for COVID-2019 (2-3%). Suspected cases must be quarantined till their test comes positive or they clear infection. At present, treatment of COVID-2019 is mostly based on the knowledge gained from the SARS and MERS outbreaks. Remdesivir, originally develop as a treatment for Ebola virus disease and Marburg virus infections, is being studied for it effectiveness against 2019-nCoV infection. Many other antiviral agents and vaccines are being tested but most of them are in phase I or II and hence unlikely to be of any benefit immediately with regards to current outbreak. Hence, the standard infection control techniques and preventive steps for healthy individuals and supportive care for the confirmed cases is the best available strategy to deal with current viral outbreak. .

COVID-19 and restrictive lung disease: A deadly combo to trip off the fine balance.

Coronavirus Disease (COVID-19) pandemic has so far led to innumerable deaths worldwide. The risk factors so far that have been most studied as poor prognostic factors are old age, individuals with multiple comorbidities and immunocompromised patients. Amongst the chronic lung diseases, most patients with COVID-19 reported so far had asthma, chronic obstructive pulmonary disease (COPD), and interstitial lung disease. Herein, we discuss the significance of restrictive lung disease during the COVID-19 pandemic as a potential risk factor via an example of a patient with kyphoscoliosis who succumbed to death due to COVID-19 pneumonia.

Cerebrovascular events in COVID-19 patients.

Neurological manifestations in patients with COVID-19 are more frequently being reported. Cerebrovascular events have been reported in around 3% of patients. In this review we summarize the published literature on cerebrovascular events in patients with COVID-19 as available on the PubMed database. So far, 3 studies have reported cerebrovascular events. Cerebrovascular events were identified on screening patients with decreased consciousness or in the presence of focal neurological deficits. These events were common in elderly, critically ill patients and in patients with prior cardio-cerebrovascular comorbidities. The diagnosis of cerebrovascular events was confirmed with computed tomography of the brain in most studies reporting neurological events. Multiple pathological mechanisms have been postulated regarding the process of neurological and vascular injury among which cytokine storm is shown to correlate with mortality. Patients with severe illness are found to have a higher cardio- cerebrovascular comorbidity. With an increasing number of cases and future prospective studies, the exact mechanism by which these cerebrovascular events occur and attribute to the poor outcome will be better understood.