Intravenous thrombolysis for multi-ethnic Asians with acute ischaemia stroke in Malaysian public primary stroke centres versus acute stroke ready hospitals: Comparison of real-world clinical outcomes

INTRODUCTION

Intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator is beneficial in acute ischaemic stroke (AIS). We aim to compare the realworld clinical outcomes and service efficiency of IVT in Malaysian primary stroke centres (PSCs) versus acute stroke ready hospitals (ASRHs).

MATERIALS AND METHODS

We conducted a multi-centre cohort study involving 5 PSCs and 7 ASRHs in Malaysia. Through review of medical records of AIS patients who received IVT from 01 January 2014 to 30 June 2021, real-world data was extracted for analysis. Univariate and multivariate regression models were employed to evaluate the role of PSCs versus ASRHs in post-IVT outcomes and complications. Statistical significance was set at p<0.05.

RESULTS

A total of 313 multi-ethnic Asians, namely 231 from PSCs and 82 from ASRHs, were included. Both groups were comparable in baseline demographic, clinical, and stroke characteristics. The efficiency of IVT delivery (door-toneedle time), functional outcomes (mRS at 3 months post- IVT), and rates of adverse events (intracranial haemorrhages and mortality) following IVT were comparable between the 2 groups. Notably, 46.8% and 48.8% of patients in PSCs and ASRHs group respectively (p=0.752) achieved favourable functional outcome (mRS≤1 at 3 months post-IVT). Regression analyses demonstrated that post-IVT functional outcomes and adverse events were independent of the role of PSCs or ASRHs.

CONCLUSION

Our study provides real-world evidence which suggests that IVT can be equally safe, effective, and efficiently delivered in ASRHs. This may encourage the establishment of more ASRHs to extend the benefits of IVT to a greater proportion of stroke populations and enhance the regional stroke care.

An analog-AI chip for energy-efficient speech recognition and transcription

Models of artificial intelligence (AI) that have billions of parameters can achieve high accuracy across a range of tasks1,2, but they exacerbate the poor energy efficiency of conventional general-purpose processors, such as graphics processing units or central processing units. Analog in-memory computing (analog-AI)3-7 can provide better energy efficiency by performing matrix-vector multiplications in parallel on 'memory tiles'. However, analog-AI has yet to demonstrate software-equivalent (SWeq) accuracy on models that require many such tiles and efficient communication of neural-network activations between the tiles. Here we present an analog-AI chip that combines 35 million phase-change memory devices across 34 tiles, massively parallel inter-tile communication and analog, low-power peripheral circuitry that can achieve up to 12.4 tera-operations per second per watt (TOPS/W) chip-sustained performance. We demonstrate fully end-to-end SWeq accuracy for a small keyword-spotting network and near-SWeq accuracy on the much larger MLPerf8 recurrent neural-network transducer (RNNT), with more than 45 million weights mapped onto more than 140 million phase-change memory devices across five chips.

Membrane disruptive action of cationic anti-bacterial peptide B1CTcu3

A twenty-two-residue peptide Brevinin1 Clinotarsus curtipus-3 (B1CTcu3), identified from the skin secretion of frog Clinotarsus curtipes of the Western Ghats, exhibited a broad range of antibacterial activity against Gram-negative and Gram-positive bacteria, including the methicillin-resistant Staphylococcus aureus (MRSA). It showed anti-biofilm activity even at sub-Minimum Inhibitory Concentration (sub-MIC) against Pseudomonas aeruginosa and Staphylococcus aureus. Analysis of the scanning electron microscopic (SEM) images, confocal images, flow cytometric data and the effect of salt concentration on antibacterial potency suggests that the killing action of the peptide is through the membranolytic process. Single channel electric recording confirmed that the peptide elicited pores on the bacterial cell membrane as it induces a heterogeneous channel in the lipid bilayer.  It also showed cytotoxicity against MDA-MB-231 breast cancer cell with IC50 of 25µM. B1CTcu3 peptide could serve as the template for next-generation antibacterial agents, particularly against antibiotic resistant pathogenic bacteria.

Novel small synthetic HIV-1 V3 crown variants: CCR5 targeting ligands

The CC chemokine receptor 5 (CCR5) antagonism represents a promising pharmacological strategy for therapeutic intervention as it plays a significant role in reducing the severity and progression of a wide range of pathological conditions. Here we designed and generated peptide ligands targeting the chemokine receptor, CCR5, that were derived from the critical interaction sites of the V3 crown domain of envelope protein glycoprotein gp120 (TRKSIHIGPGRAFYTTGEI) of HIV-1 using computational biology approach and the peptide sequence corresponding to this region was taken as the template peptide, designated as TMP-1. The peptide variants were synthesized by employing Fmoc chemistry using polymer support and were labelled with rhodamine B to study their interaction with the CCR5 receptor expressed on various cells. TMP-1 and TMP-2 were selected as the high-affinity ligands from in vitro receptor-binding assays. Specific receptor-binding experiments in activated peripheral blood mononuclear cells and HOS.CCR5 cells indicated that TMP-1 and TMP-2 had significant CCR5 specificity. Further, the functional analysis of TMP peptides using chemotactic migration assay showed that both peptides did not mediate the migration of responsive cells. Thus, template TMP-1 and TMP-2 represent promising CCR5 targeting peptide candidates.

Olfactory dysfunction amongst children and adolescents with laboratory confirmed coronavirus disease 2019: a systematic review

BACKGROUND

Despite the rapidly emerging reports of olfactory dysfunction amongst adult patients with coronavirus disease 2019, cases involving children and adolescents are scarcely reported. The literature was reviewed to elucidate olfactory dysfunction amongst children and adolescents with coronavirus disease 2019.

METHODS

A search of the literature published from 1 December 2019 to 30 April 2021 was conducted using four databases, based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. The search was performed over one month (May 2021).

RESULTS

Only 9 articles were identified, with a total of 316 laboratory confirmed coronavirus disease 2019 positive children and adolescents, of whom 156 reported olfactory dysfunction. Four studies reported olfactory dysfunction based on subjective tests; four studies carried out objective assessment. Most studies reported on olfaction recovery.

CONCLUSION

The literature review revealed an olfactory dysfunction rate of 49 per cent amongst children and adolescents with coronavirus disease 2019. Persistence of olfactory dysfunction was reported in 7.1 per cent of the patients. Further studies involving objective measures need to be carried out in children and adolescents with coronavirus disease 2019.

Aberrantly low STAT3 and STAT5 responses are associated with poor outcome and an inflammatory gene expression signature in pediatric acute myeloid leukemia

The relapse rate for children with acute myeloid leukemia is nearly 40% despite aggressive chemotherapy and often stem cell transplant. We sought to understand how environment-induced signaling responses are associated with clinical response to treatment. We previously reported that patients whose AML cells showed low G-CSF-induced STAT3 activation had inferior event-free survival compared to patients with stronger STAT3 responses. Here, we expanded the paradigm to evaluate multiple signaling parameters induced by a more physiological stimulus. We measured STAT3, STAT5 and ERK1/2 responses to G-CSF and to stromal cell-conditioned medium for 113 patients enrolled on COG trials AAML03P1 and AAML0531. Low inducible STAT3 activity was independently associated with inferior event-free survival in multivariate analyses. For inducible STAT5 activity, those with the lowest and highest responses had inferior event-free survival, compared to patients with intermediate STAT5 responses. Using existing RNA-sequencing data, we compared gene expression profiles for patients with low inducible STAT3/5 activation with those for patients with higher inducible STAT3/5 signaling. Genes encoding hematopoietic factors and mitochondrial respiratory chain subunits were overexpressed in the low STAT3/5 response groups, implicating inflammatory and metabolic pathways as potential mechanisms of chemotherapy resistance. We validated the prognostic relevance of individual genes from the low STAT3/5 response signature in a large independent cohort of pediatric AML patients. These findings provide novel insights into interactions between AML cells and the microenvironment that are associated with treatment failure and could be targeted for therapeutic interventions.

Maturational Changes in Mouse Cutaneous Touch and Piezo2-Mediated Mechanotransduction

The age of studied animals has a profound impact on experimental outcomes in animal-based research. In mice, age influences molecular, morphological, physiological, and behavioral parameters, particularly during rapid postnatal growth and maturation until adulthood (at 12 weeks of age). Despite this knowledge, most biomedical studies use a wide-spanning age range from 4 to 12 weeks, raising concerns about reproducibility and potential masking of relevant age differences. Here, using mouse behavior and electrophysiology in cultured dorsal root ganglia (DRG), we reveal a decline in behavioral cutaneous touch sensitivity and Piezo2-mediated mechanotransduction in vitro during mouse maturation but not thereafter. In addition, we identify distinct transcript changes in individual Piezo2-expressing mechanosensitive DRG neurons by combining electrophysiology with single-cell RNA sequencing (patch-seq). Taken together, our study emphasizes the need for accurate age matching and uncovers hitherto unknown maturational plasticity in cutaneous touch at the level of behavior, mechanotransduction, and transcripts.

Crystal structure determination of two pyridine derivatives: 4-[(E)-2-(4-methoxyphenyl)ethenyl]-1-methylpyridin-1-ium hexafluoro-λ6-phosphane and 4-[(E)-2-[4-(dimethylamino)phenyl]ethenyl]-1-phenyl-1λ5-pyridin-1-ylium hexafluoro-λ6-phosphane

In both title pyridine derivatives, (I) and (II), the cation adopts an E configuration with respect to the C=C. In compound (I), the PF₆⁻ anion is disordered with occupancy factors of 0.614 (7):0.386 (7). In both the compounds, the crystal packing is stabilized by C—H⋯F inter­molecular inter­actions results into two-dimensional mol­ecular sheets, which are formed by (14) ring motifs in compound (I), (40) ring motifs in compound (II). In addition to that, the crystal packing is further stabilized by P—F⋯π inter­actions in compound (I) and π–π in compound (II).

The title mol­ecular salts, C₁₆H₁₆NO⁺·PF₆⁻, (I), and C₂₁H₂₁N₂⁺·PF₆⁻, (II), are pyridine derivatives. In compound (I), the cation comprises a methyl N-substituted pyridine ring and a meth­oxy-substituted benzene ring connected by a C=C double bond. The F atoms of the PF₆⁻ anion are disordered over two sets of sites with refined occupancy factors of 0.614 (7):0.386 (7). In compound (II), the cation comprises a pyridine ring attached to unsubstituted phenyl ring and a di­methyl­aniline ring, which are connected by a C=C double bond. The anion is PF₆⁻. In both salts, the cation adopts an E configuration with respect to the C=C bond. The pyridine ring makes a dihedral angle of 9.86 (12)° with the meth­oxy-substituted benzene ring in compound (I) and 11.2 (3)° with the di­methyl­amine-substituted benzene ring in compound (II). In compound (I), the crystal packing is stabilized by weak C—H⋯F inter­molecular inter­actions which result in R⁴₃(14) ring motifs, forming mol­ecular sheets running parallel to (03). These are further stabilized by weak P—F⋯π interactions. In compound (II), the crystal packing is stabilized by C—H⋯F inter­actions, which result in R⁶₆(40) ring motifs, forming mol­ecular sheets running parallel to (101) and these are further connected by π–π inter­actions.

Myotubularin related protein-2 and its phospholipid substrate PIP2 control Piezo2-mediated mechanotransduction in peripheral sensory neurons

Piezo2 ion channels are critical determinants of the sense of light touch in vertebrates. Yet, their regulation is only incompletely understood. We recently identified myotubularin related protein-2 (Mtmr2), a phosphoinositide (PI) phosphatase, in the native Piezo2 interactome of murine dorsal root ganglia (DRG). Here, we demonstrate that Mtmr2 attenuates Piezo2-mediated rapidly adapting mechanically activated (RA-MA) currents. Interestingly, heterologous Piezo1 and other known MA current subtypes in DRG appeared largely unaffected by Mtmr2. Experiments with catalytically inactive Mtmr2, pharmacological blockers of PI(3,5)P₂ synthesis, and osmotic stress suggest that Mtmr2-dependent Piezo2 inhibition involves depletion of PI(3,5)P₂. Further, we identified a PI(3,5)P₂ binding region in Piezo2, but not Piezo1, that confers sensitivity to Mtmr2 as indicated by functional analysis of a domain-swapped Piezo2 mutant. Altogether, our results propose local PI(3,5)P₂ modulation via Mtmr2 in the vicinity of Piezo2 as a novel mechanism to dynamically control Piezo2-dependent mechanotransduction in peripheral sensory neurons.

We often take our sense of touch for granted. Yet, our every-day life greatly depends on the ability to perceive our environment to alert us of danger or to further social interactions, such as mother-child bonding. Our sense of touch relies on the conversion of mechanical stimuli to electrical signals (this is known as mechanotransduction), which then travel to brain to be processed. This task is fulfilled by specific ion channels called Piezo2, which are activated when cells are exposed to pressure and other mechanical forces. These channels can be found in sensory nerves and specialized structures in the skin, where they help to detect physical contact, roughness of surfaces and the position of our body parts.

It is still not clear how Piezo2 channels are regulated but previous research by several laboratories suggests that they work in conjunction with other proteins. One of these proteins is the myotubularin related protein-2, or Mtmr2 for short. Now, Narayanan et al. – including some of the researchers involved in the previous research – set out to advance our understanding of the molecular basis of touch and looked more closely at Mtmr2.

To test if Mtmr2 played a role in mechanotransduction, Narayanan et al. both increased and reduced the levels of this protein in sensory neurons of mice grown in the laboratory. When Mtmr2 levels were low, the activity of Piezo2 channels increased. However, when the protein levels were high, Piezo2 channels were inhibited. These results suggest that Mtmr2 can control the activity of Piezo2. Further experiments, in which Mtmr2 was genetically modified or sensory neurons were treated with chemicals, revealed that Mtmr2 reduces a specific fatty acid in the membrane of nerve cells, which in turn attenuates the activity of Piezo2.

This study identified Mtmr2 and distinct fatty acids in the cell membrane as new components of the complex setup required for the sense of touch. A next step will be to test if these molecules also influence the activity of Piezo2 when the skin has become injured or upon inflammation.

Crystal structures of three 1-oxo-1,2-dihydronaphthalene derivatives: dimethyl 4-(4-methoxyphenyl)-2-(4-methylphenyl)-1-oxo-1,2-dihydronaphthalene-2,3-dicarboxylate, dimethyl 1-oxo-2-(pyren-4-yl)-4-(thiophen-2-yl)-1,2-dihydronaphthalene-2,3-dicarboxylate and ethyl 1-oxo-2-phenyl-2,4-bis(thiophen-2-yl)-1,2-dihydronaphthalene-3-carboxylate

In the title 1-oxo-1,2-di­hydro­naphthalene derivatives, the cyclo­hexa-1,3-diene rings of the 1,2-di­hydro­naphthalene ring systems adopt half-chair, boat and half-chair conformations, respectively. In the crystal of the methyl­phenyl compound, the mol­ecules are linked via C—H⋯O, C—H⋯π and π–π inter­actions, forming a double-chain structure, while in the crystals of the other two compounds, mol­ecules are linked by π–π inter­actions, forming a chain structure.

In the title 1-oxo-1,2-di­hydro­naphthalene derivatives, C₂₈H₂₄O₆, (I), C₃₄H₂₂O₅S, (II), and C₂₇H₂₀O₃S₂, (III), the cyclo­hexa-1,3-diene rings of the 1,2-di­hydro­naphthalene ring systems adopt half-chair, boat and half-chair conformations, respectively. The carbonyl O atoms attached to the di­hydro­naphthalene ring systems are each significantly deviated from the mean plane of the 1,2-di­hydro­naphthalene ring system, by 0.6162 (12) Å in (I), 0.6016 (16) Å in (II) and 0.515 (3) Å in (III). The mean planes of the 1,2-di­hydro­naphthalene ring systems make dihedral angles of 85.83 (3), 88.19 (3) and 81.67 (8)°, respectively, with the methyl­phenyl ring in (I), the pyrene ring in (II) and the phenyl ring in (III). In (I), the mol­ecular structure is stabilized by an intra­molecular C—H⋯O hydrogen bond, generating an S(6) ring motif. In the crystal of (I), mol­ecules are linked by an inter­molecular C—H⋯O hydrogen bond, which generates a C(8) zigzag chain running along [100]. Adjacent chains are further connected by C—H⋯π and offset π–π inter­actions [centroid–centroid distance = 3.6572 (9) Å], forming a double-chain structure. In the crystals of (II) and (III), mol­ecules are linked into chain structures by offset π–π inter­actions with centroid–centroid distances of 3.5349 (12) and 3.8845 (13) Å for (II) and 3.588 (2) Å for (III). In (II) and (III), the thio­phene rings are orientationally disordered over two sites, with occupancy ratios of 0.69:0.31 for (II), and 0.528 (4):0.472 (4) and 0.632 (5):0.368 (5) for (III).

Nocistatin sensitizes TRPA1 channels in peripheral sensory neurons

The ability of sensory neurons to detect potentially harmful stimuli relies on specialized molecular signal detectors such as transient receptor potential (TRP) A1 ion channels. TRPA1 is critically implicated in vertebrate nociception and different pain states. Furthermore, TRPA1 channels are subject to extensive modulation and regulation - processes which consequently affect nociceptive signaling. Here we show that the neuropeptide Nocistatin sensitizes TRPA1-dependent calcium influx upon application of the TRPA1 agonist mustard oil (MO) in cultured sensory neurons of dorsal root ganglia (DRG). Interestingly, TRPV1-mediated cellular calcium responses are unaffected by Nocistatin. Furthermore, Nocistatin-induced TRPA1-sensitization is likely independent of the Nocistatin binding partner 4-Nitrophenylphosphatase domain and non-neuronal SNAP25-like protein homolog 1 (NIPSNAP1) as assessed by siRNA-mediated knockdown in DRG cultures. In conclusion, we uncovered the sensitization of TRPA1 by Nocistatin, which may represent a novel mechanism how Nocistatin can modulate pain.

Crystal structures of three carbazole derivatives: 12-ethyl-7-phenylsulfonyl-7H-benzofuro[2,3-b]carbazole, (1), 2-(4,5-dimethoxy-2-nitrophenyl)-4-hydroxy-9-phenylsulfonyl-9H-carbazole-3-carbaldehyde, (2), and 12-phenyl-7-phenylsulfonyl-7H-benzofuro[2,3-b]carbazole, (3)

The three title compounds, C26H19NO3S, (1), C27H20N2O8S, (2), and C30H19NO3S, (3), are carbazole derivatives, where (1) and (3) are heterocycle-containing carbazoles with a benzofuran moiety fused to a carbazole unit. In (2), a dimethoxynitrophenyl ring is attached to the carbazole moiety. In the three derivatives, a phenylsulfonyl group is attached to the N atom of the carbazole unit. Compound (1) crystallizes with two independent molecules in the asymmetric unit (AandB). The carbazole skeleton in the three compounds is essentially planar. In compound (1), the benzene ring of the phenylsulfonyl moiety is almost orthogonal to the carbazole moiety, with dihedral angles of 85.42 (9) and 84.52 (9)° in moleculesAandB, respectively. The benzene ring of the phenylsulfonyl group in compounds (2) and (3) are inclined to the carbazole moiety, making dihedral angles of 70.73 (13) and 81.73 (12)°, respectively. The S atom has a distorted tetrahedral configuration in all three compounds. In the crystals, C—H...O hydrogen bonds give rise toR22(12) inversion dimers for compound (1), and toR22(24) inversion dimers andR44(40) ring motifs for compound (2). The crystal packing in (1) also features C—H...π and π–π interactions [shortest intercentroid distance = 3.684 (1) Å], leading to supramolecular three-dimensional aggregation. In the crystal of compound (2), the combination of the various C—H...O hydrogen bonds leads to the formation of a three-dimensional network. In the crystal of compound (3), molecules are linked by C—H...O hydrogen bonds, forming chains running parallel to theaaxis, and the chains are linked by C—H...π interactions, forming corrugated sheets parallel to theabplane.

Crystal structures of two new carbazole derivatives: 12-(4-nitrophenyl)-7-phenylsulfonyl-7H-benzofuro[2,3-b]carbazole and 2-methyl-4-(4-nitrophenyl)-9-phenylsulfonyl-9H-thieno[2,3-b]carbazole

The title compounds are carbazole derivatives, with a benzo­furan ring system in (I) and a methyl­thio­phene ring in (II) fused with the respective carbazole moiety. In the crystals of both compounds, mol­ecules are linked via C—H⋯O hydrogen bonds, forming sheets lying parallel to (10).

The title compounds, C₃₀H₁₈N₂O₅S, (I), and C₂₇H₁₈N₂O₄S₂, (II), are carbazole derivatives with a phenyl­sulfonyl group and a nitro­phenyl group attached to the carbazole moiety in identical positions in both mol­ecules. A benzo­furan ring system in (I) and a methyl­thio­phene ring in (II) are fused with the respective carbazole moieties on the same sides. The mean plane of the carbazole ring system makes a dihedral angle of 3.17 (7)° with the benzo­furan ring system in (I) and a dihedral angle of 3.39 (11)° with the methyl­thio­phene ring in (II), implying that both fused units are essentially planar. The mean planes of the carbazole ring systems in both the compounds are almost orthogonal to the respective nitro-substituted phenyl rings, making dihedral angles of 75.64 (10) and 77.63 (12)° in compounds (I) and (II), respectively. In (I), the phenyl­sulfonyl ring system is positionally disordered with a refined occupancy ratio of 0.63 (2):0.37 (2). In both compounds, the mol­ecular structures are stabilized by intra­molecular C—H⋯O hydrogen bonds, generating S(6) ring motifs with the sulfone group O atoms. In the crystal of compound (I), mol­ecules are linked by pairs of C—H⋯O hydrogen bonds, which generate R₂²(18) inversion dimers, and inter­connected by C(14) chains running along the c-axis direction, whereas in compound (II), the C—H⋯O hydrogen bonds generate R₄³(37) ring motifs. In the crystals of both compounds, C—H⋯O hydrogen-bonded sheets are formed lying parallel to (10-1). In addition, C—H⋯π and offset π–π inter­actions [inter­centroid distance = 3.7158 (14) Å in (I) and 3.9040 (15) Å in (II)] are also present in the crystals of both compounds.

Native Piezo2 Interactomics Identifies Pericentrin as a Novel Regulator of Piezo2 in Somatosensory Neurons

The ability of somatosensory neurons to perceive mechanical stimuli relies on specialized mechanotransducing proteins and their molecular environment. Only recently has the identity of a major transducer of mechanical forces in vertebrates been revealed by the discovery of Piezo2. Further work has established its pivotal role for innocuous touch in mice. Therefore, Piezo2 offers a unique platform for the molecular investigation of somatosensory mechanosensation. We performed a mass spectrometry-based interactomics screen on native Piezo2 in somatosensory neurons of mouse dorsal root ganglia (DRG). Stringent and quantitative data analysis yielded the identity of 36 novel binding partners of Piezo2. The biological significance of this data set is reflected by functional experiments demonstrating a role for Pericentrin in modulating Piezo2 activity and membrane expression in somatosensory neurons. Collectively, our findings provide a framework for understanding Piezo2 physiology and serve as a rich resource for the molecular dissection of mouse somatosensation.

Comparison of nested-multiplex, Taqman & SYBR Green real-time PCR in diagnosis of amoebic liver abscess in a tertiary health care institute in India

BACKGROUND & OBJECTIVES

Amoebiasis is a common parasitic infection caused by Entamoeba histolytica and amoebic liver abscess (ALA) is the most common extraintestinal manifestation of amoebiasis. The aim of this study was to standardise real-time PCR assays (Taqman and SYBR Green) to detect E. histolytica from liver abscess pus and stool samples and compare its results with nested-multiplex PCR.

METHODS

Liver abscess pus specimens were subjected to DNA extraction. The extracted DNA samples were subjected to amplification by nested-multiplex PCR, Taqman (18S rRNA) and SYBR Green real-time PCR (16S-like rRNA assays to detect E. histolytica/E. dispar/E. moshkovskii). The amplification products were further confirmed by DNA sequence analysis. Receiver operator characteristic (ROC) curve analysis was done for nested-multiplex and SYBR Green real-time PCR and the area under the curve was calculated for evaluating the accuracy of the tests to dignose ALA.

RESULTS

In all, 17, 19 and 25 liver abscess samples were positive for E. histolytica by nested-multiplex PCR, SYBR Green and Taqman real-time PCR assays, respectively. Significant differences in detection of E. histolytica were noted in the real-time PCR assays evaluated ( P<0.0001). The nested-multiplex PCR, SYBR Green real-time PCR and Taqman real-time PCR evaluated showed a positivity rate of 34, 38 and 50 per cent, respectively. Based on ROC curve analysis (considering Taqman real-time PCR as the gold standard), it was observed that SYBR Green real-time PCR was better than conventional nested-multiplex PCR for the diagnosis of ALA.

INTERPRETATION & CONCLUSIONS

Taqman real-time PCR targeting the 18S rRNA had the highest positivity rate evaluated in this study. Both nested multiplex and SYBR Green real-time PCR assays utilized were evaluated to give accurate results. Real-time PCR assays can be used as the gold standard in rapid and reliable diagnosis, and appropriate management of amoebiasis, replacing the conventional molecular methods.

Alternatively Spliced Isoforms of KV10.1 Potassium Channels Modulate Channel Properties and Can Activate Cyclin-dependent Kinase in Xenopus Oocytes

K_V10.1 is a voltage-gated potassium channel expressed selectively in the mammalian brain but also aberrantly in cancer cells. In this study we identified short splice variants of K_V10.1 resulting from exon-skipping events (E65 and E70) in human brain and cancer cell lines. The presence of the variants was confirmed by Northern blot and RNase protection assays. Both variants completely lacked the transmembrane domains of the channel and produced cytoplasmic proteins without channel function. In a reconstituted system, both variants co-precipitated with the full-length channel and induced a robust down-regulation of K_V10.1 current when co-expressed with the full-length form, but their effect was mechanistically different. E65 required a tetramerization domain and induced a reduction in the overall expression of full-length K_V10.1, whereas E70 mainly affected its glycosylation pattern. E65 triggered the activation of cyclin-dependent kinases in Xenopus laevis oocytes, suggesting a role in cell cycle control. Our observations highlight the relevance of noncanonical functions for the oncogenicity of K_V10.1, which need to be considered when ion channels are targeted for cancer therapy.

Modulation of nociceptive ion channels and receptors via protein-protein interactions: implications for pain relief

In the last 2 decades biomedical research has provided great insights into the molecular signatures underlying painful conditions. However, chronic pain still imposes substantial challenges to researchers, clinicians and patients alike. Under pathological conditions, pain therapeutics often lack efficacy and exhibit only minimal safety profiles, which can be largely attributed to the targeting of molecules with key physiological functions throughout the body. In light of these difficulties, the identification of molecules and associated protein complexes specifically involved in chronic pain states is of paramount importance for designing selective interventions. Ion channels and receptors represent primary targets, as they critically shape nociceptive signaling from the periphery to the brain. Moreover, their function requires tight control, which is usually implemented by protein-protein interactions (PPIs). Indeed, manipulation of such PPIs entails the modulation of ion channel activity with widespread implications for influencing nociceptive signaling in a more specific way. In this review, we highlight recent advances in modulating ion channels and receptors via their PPI networks in the pursuit of relieving chronic pain. Moreover, we critically discuss the potential of targeting PPIs for developing novel pain therapies exhibiting higher efficacy and improved safety profiles.

Crystal structures and conformations of two Diels-Alder adduct derivatives: 1,8-bis-(thio-phen-2-yl)-14-oxa-tetra-cyclo-[6.5.1.0(2,7).0(9,13)]tetra-deca-2(7),3,5-trien-10-one and 1,8-diphenyl-14-oxa-tetra-cyclo[6.5.1.0(2,7).0(9,13)] tetra-deca-2,4,6-trien-10-one

The title compounds, C21H16O2S2 (I) and C25H20O2 (II), are products of a tandem 'pincer' Diels-Alder reaction consisting of [2 + 2] cyclo-additions between benzo[c]furan and cyclo-penta-none. Each comprises a fused tetra-cyclic ring system containing two five-membered rings (in envelope conformations with the O atom as the flap) and six-membered rings (in boat conformations). In addition, two thio-phene rings in (I) and two phenyl rings in (II) are attached to the tetra-cyclic ring system. The cyclo-penta-none ring adopts a twisted conformation in (I) and an envelope conformation in (II). In (I), the thio-phene rings are positionally disordered over two sets of sites, with occupancy ratios of 0.901 (2):0.099 (2) and 0.666 (2):0.334 (2). In (II), the oxygen atom of the cyclo-penta-none ring is rotationally disordered over two sites with an occupancy ratio of 0.579 (4):0.421 (4). The mol-ecular structure of (I) is stabilized by an intra-molecular C-H⋯O hydrogen bond, which generates an S(7) ring motif. In the crystal, the mol-ecules are linked via weak C-H⋯O hydrogen bonds, which generate R (2) 2(16) ring motifs in (I) and C(8) chains in (II). In both structures, the crystal packing also features C-H⋯π inter-actions. The crystal studied of compound (I) was twinned by non-merohedry. The twin component is related by the twin law [-1 0 0 -0.101 1 -0.484 0 0 -1] operated by a twofold rotation axis parallel to the b axis. The structure of (I) was refined with a twin scale factor of 0.275 (2).

A case of pediatric acute lymphoblastic leukemia with invasive candidiasis: short review

Mortality rate associated with invasive fungal infections is very high. Early suspicion for fungal infections is important during intensive chemotherapy for acute leukemia. Empirical treatment with antifungals amphotericin B or caspofungin should be started if patient is not responding to broad spectrum antibiotics and if expected duration of neutropenia is prolonged. We are reporting a 3 years old girl child with diagnosis of pre-B acute lymphoblastic leukemia who developed invasive candidiasis with typical clinical and radiological findings during induction chemotherapy. Candida non-albicans was isolated and she was treated with amphotericin B followed by caspofungin. Patient deteriorated after initial response and succumbed to death. Species identification and sensitivity pattern of fungus can help in selecting appropriate antifungal drug.

Crystal structure of 2,9-diphenyl-17λ6-thiatetracyclo[8.7.0.03,8.011,16]heptadeca-1(10),2,4,6,8,11(16),12,14-octaene-17,17-dione

The title compound, C₂₈H₁₈O₂S, is composed of a naphthalene ring system fused with a benzo­thio­phene ring and attached to two phenyl rings. The phenyl rings make dihedral angles of 70.92 (8) and 79.23 (8)° with the essentially planar naphthalene ring system (r.m.s. deviation = 0.031 Å). There is an intra­molecular C—H⋯π inter­action present. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds which generate C(7) zigzag chains running parallel to [10-1]. The chains are linked via further C—H⋯π inter­actions, forming a three-dimensional structure.

3,10,14,21-Tetra-kis(4-meth-oxy-phen-yl)penta-cyclo-[11.8.0.0(2,11).0(4,9).0(15,20)]henicosa-1(21),2,4(9),5,7,10,13,15(20),16,18-decaen-12-one chloro-form monosolvate

The asymmetric unit of the title compound, C₄₉H₃₆O₆·CHCl₃, contains half an organic mol­ecule, the complete mol­ecule being generated by the operation of a crystallographic twofold rotation axis, and half a highly disordered chloro­form mol­ecule. The contribution to the diffraction pattern of the latter was removed using the program SQUEEZE in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155]; the unit-cell characteristics take into account the presence of CHCl₃. The dihedral angles between the planes of the naphthalene ring system and the meth­oxy­benzene rings are 71.05 (7) (syn to the central C=O group) and 57.27 (6)° (anti to the central C=O group). In the crystal, mol­ecules are linked by C—H⋯O inter­actions, generating C(12) chains running parallel to the b axis.

Afro Middle East Asian symposium on cancer cooperation

This manuscript captures the discussion and recommendations that came out of a special Afro Asian symposium involving 13 countries. Unmet needs and cost-effective solutions with special emphasis on training form the backbone of practical next steps.

2-(4,5-Dimeth-oxy-2-nitro-phen-yl)-4-meth-oxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde

In the title compound, C₂₈H₂₂N₂O₈S, the carbazole ring system is roughly planar, with a maximum deviation of 0.084 (3) Å for the C atom connected to the 4,5-dimeth­oxy-2-nitro­phenyl ring. The dihedral angle between the carbazole system and the dimeth­oxy-substituted nitro­phenyl ring is 57.05 (10)°. The aldehyde C atom deviates by 0.164 (5) Å from its attached carbazole ring system. The mol­ecular structure is stabilized by C—H⋯O inter­actions which generate two S(6) and one S(7) ring motif. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, forming R₃³(15) ring motifs, which are further crosslinked by R₃²(19) ring motifs, resulting in (002) layers. The crystal packing also features C—H⋯π inter­actions.

Methyl 3′-(2,5-dimethylbenzyl)-1′-methyl-2-oxo-4′-phenylspiro[indoline-3,2′-pyrrolidine]-3′-carboxylate chloroform monosolvate

In the title solvate, C₂₉H₃₀N₂O₃·CHCl₃, the dihedral angle between the indole ring system (r.m.s. deviation = 0.050 Å) and the 4-methyl­pyrrolidine ring is 88.88 (8)°. The latter ring adopts an envelope conformation with the N atom as the flap. Its mean plane makes dihedral angles of 86.94 (11) and 42.08 (9)° with the phenyl and di­methyl­benzene rings, respectively. The mol­ecular conformation is stabilized by intra­molecular C—H⋯O hydrogen bonds, which generate S(6) and S(9) ring motifs. The chloro­form solvent mol­ecule is linked to the organic mol­ecule by a C—H⋯O hydrogen bond involving the carbonyl O atom of the carboxyl­ate group. In the crystal, mol­ecules are linked via bifurcated N—H⋯(N,O) and C—H⋯O hydrogen bonds, forming chains propagating along [001].

Methyl 3′-benzyl-4′-(2,4-dichlorophenyl)-1′-methyl-2-oxospiro[indoline-3,2′-pyrrolidine]-3′-carboxylate

In the title compound, C₂₇H₂₄Cl₂N₂O₃, the indole ring system is essentially planar, with a maximum deviation of 0.082 (2) Å for the carbonyl C atom. It makes a dihedral angle of 88.53 (6)° with the mean plane of the 4-methyl­pyrrolidine ring, which adopts an envelope conformation with the N atom at the flap position. The mol­ecular structure is stabilized by intra­molecular C—H⋯O hydrogen bonds, which generate S(6) and S(7) ring motifs, and an intra­molecular π–π inter­action involving the benzyl and di­chloro-substituted benzene rings [centroid–centroid distance = 3.6291 (11) Å]. In the crystal, mol­ecules are linked via N—H⋯O hydrogen bonds, forming C(7) chains running parallel to [10-1].

2-(4,5-Dimethoxy-2-nitrophenyl)-4-methoxy-3-methyl-9-phenylsulfonyl-9H-carbazole

In the title compound, C₂₈H₂₄N₂O₇S, the carbazole system is essentially planar, with a maximum deviation of 0.0644 (19) Å for the C atom connected to the 4,5-dimeth­oxy-2-nitro­phenyl group. The dihedral angle between the carbazole moiety and the dimethoxy-substituted nitrophenyl ring is 58.55 (7)°. The sulfonyl group forms two intra­molecular C—H⋯O bonds with the adjacent carbazole system, forming two cyclic S(6) motifs. In the crystal, mol­ecules are linked along the a axis in bands consisting of cyclic R₃³(15) motifs through two further C—H⋯O hydrogen bonds.

2-(4,5-Di-chloro-2-nitro-phen-yl)-4-meth-oxy-3-methyl-9-phenyl-sulfon-yl-9H-carbazole

In the title compound, C₂₆H₁₈Cl₂N₂O₅S, the carbazole ring system is essentially planar with a maximum deviation of 0.0498 (16) Å for the N atom. The carbazole ring system is almost orthogonal to the phenyl­sulfonyl and di­chloro-substituted nitro­phenyl rings, making dihedral angles of 84.23 (7) and 85.46 (12)°, respectively. The mol­ecular structure features intra­molecular C—H⋯O inter­actions, which generate two S(6) ring motifs. In the crystal, mol­ecules are linked by C—Cl⋯O halogen bonds [3.016 (3) Å, 166.63 (5)°], which generate infinite C(8) chains running parallel to [010].

2-(4-Chloro-2-nitrophenyl)-4-methoxy-9-phenylsulfonyl-9H-carbazole-3-carbaldehyde

In the sterically hindered title compound, C₂₆H₁₇ClN₂O₆S, the carbazole ring has a maximum deviation from planarity of 0.067 (4) Å for the C atom connected to the aldehyde group. The carbazole moiety forms a dihedral angle of 72.8 (1)° with the nitro-substituted benzene ring. The O atom of the meth­oxy group deviates by 0.186 (1) Å from the adjacent carbazole moiety. The phenyl­sulfonyl group forms intra­molecular C—H⋯O bonds between sulfone O atoms and the carbazole moiety, resulting in two S(6) rings. In the crystal, the nitrated benzene rings are linked via C—H⋯O inter­actions forming infinite C(7) chains along [100]. The crystal packing is also characterized by C—H⋯π inter­actions, which result in inversion dimers.

Association between proinflammatory cytokines and lipid peroxidation in patients with severe dengue disease around defervescence

OBJECTIVES

Proinflammatory cytokines and the oxidative stress response are reported to be involved in dengue viral disease. The present study investigated the correlation of proinflammatory cytokines and lipid peroxidation with dengue severity.

METHODS

Clinical samples from 27 dengue fever (DF) cases, 30 dengue haemorrhagic fever (DHF) cases, and 24 dengue shock syndrome (DSS) cases were studied around defervescence, along with samples from 30 healthy controls. Plasma samples were analysed for tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) by ELISA and for malondialdehyde (MDA) by thiobarbituric acid assay.

RESULTS

Dengue-infected individuals had significantly higher levels of TNF-α, IFN-γ, and MDA in comparison to controls. The ratio of TNF-α to IFN-γ was significantly higher in DHF and DSS than in DF. A TNF-α/IFN-γ ratio value of 5.69 around defervescence predicted DHF and DSS with moderate accuracy and thus may serve as an indicator to study dengue severity. The study observed a significant positive correlation of lipid peroxides with TNF-α levels and the TNF-α/IFN-γ ratio in severe dengue cases.

CONCLUSIONS

We propose that the oxidative stress response induced by the dengue virus may trigger the inflammatory cytokine responses in dengue severity and thereby contributes to the pathogenesis of the disease; however the interplay between the oxidative response and inflammatory activity in disease virulence needs further study.

rac-4-(4-Chloro-phen-yl)-2-methyl-amino-3-nitro-5,6,7,8-tetra-hydro-4H-chromen-5-one

The title compound, C16H15ClN2O4, contains a chiral centre and crystallizes as a racemate. The methyl-ene group β-positioned to the carbonyl group is partially (21%) disordered. It flips to the opposite sides of the corresponding six-membered carbocycle by -0.304 (3) and 0.197 (11) Å, producing alternative envelope conformations. The planes of the pyran and chloro-phenyl rings form a dihedral angle of 86.25 (9)°. The mol-ecular structure is characterized by an intra-molecular N-H⋯O inter-action, which generates an S(6) ring motif. The corresponding amino N atom deviates from the plane of the pyran ring by 0.1634 (19) Å. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming C(8) chains running parallel to the b-axis direction. The crystal structure also features C-H⋯π inter-actions.

(4S*)-2-Methyl-amino-3-nitro-4-(4-nitro-phen-yl)-5,6,7,8-tetra-hydro-4H-chromen-5-one

The title compound, C16H15N3O6, is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The six-membered carbocyclic ring adopts an envelope conformation with the central CH2 C atom as the flap. The amine N atom deviates from the mean plane of the pyran ring by 0.1365 (15) Å. The nitro-phenyl ring is almost orthogonal to the pyran ring and the mean plane of the six-membered carbocyclic ring, the dihedral angle between their mean planes being 88.30 (7) and 87.61 (8)°, respectively. The mol-ecular structure is stabilized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming infinite bands lying parallel to (-110) and composed of alternate R 2 (2)(24) and R 2 (4)(12) graph-set ring motifs. The crystal structure is further stabilized by C-H⋯π inter-actions, forming a three-dimensional structure.

4-(4-Bromo-phen-yl)-2-methyl-amino-3-nitro-5,6,7,8-tetra-hydro-4H-chromen-5-one

In the title compound, C₁₆H₁₅BrN₂O₄, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the disordered methyl­ene C atom as the flap. The pyran ring is almost orthogonal to the chloro­phenyl ring, making a dihedral angle of 87.11 (12)°. The amine-group N atom deviates significantly from the pyran ring [0.238 (3) Å]. The mol­ecular structure is stabilized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, which generate C(8) chains running parallel to the b axis. The chains are linked by C—H⋯π inter­actions. The methyl­ene-group C atom of the chromene system that is disordered, along with its attached H atoms and the H atoms on the two adjacent C atoms, has an occupancy ratio of 0.791 (7):0.209 (7).

Rapid plasticity of motor corticospinal system with robotic reach training

Goal-directed reaching is important for the activities of daily living. Populations of neurons in the primary motor cortex that project to spinal motor circuits are known to represent the kinematics of reaching movements. We investigated whether repetitive practice of goal-directed reaching movements induces use-dependent plasticity of those kinematic characteristics, in a manner similar to finger movements, as had been shown previously. Transcranial magnetic stimulation (TMS) was used to evoke upper extremity movements while the forearm was resting in a robotic cradle. Plasticity was measured by the change in kinematics of these evoked movements following goal-directed reaching practice. Baseline direction of TMS-evoked arm movements was determined for each subject. Subjects then practiced three blocks of 160 goal-directed reaching movements in a direction opposite to the baseline direction (14 cm reach 180° from baseline direction) against a 75-Nm spring field. Changes in TMS-evoked whole arm movements were assessed after each practice block and after 5 min following the end of practice. Direction and the position of the point of peak velocity of TMS-evoked movements were significantly altered following training and at a 5-min interval following training, while amplitude did not show significant changes. This was accompanied by changes in the motor-evoked potentials (MEPs) of the shoulder and elbow agonist muscles that partly explained the change in direction, mainly by increase in agonist MEP, without significant changes in antagonists. These findings demonstrate that the arm representation accessible by motor cortical stimulation under goes rapid plasticity induced by goal-directed robotic reach training in healthy subjects.

Retropharyngeal abscess - A complication of laryngeal mask airway

Retropharyngeal or parapharyngeal abscesses developing after intubation are rare. This can present as surgical emergency post extubation. We report a case of retropharyngeal abscess that probably occurred as a complication of laryngeal mask insertion.

4-(2-Benzoyl-benzoyl)-N,N-diphenyl-aniline

The asymmetric unit of the title compound, C₃₂H₂₃NO₂, comprises two crystallographically independent mol­ecules. In both mol­ecules, the geometries about the N atoms deviate significantly from the ideal trigonal–planar geometry with bond-angle sums about the N atom of 359.32° in one mol­ecule and 359.86° in the other. The O atoms of the carbonyl groups are deviated significantly from the central benzene rings by 0.6747 (14) and −1.1223 (13) Å in one molecule and −0.6230 (13) and 1.1559 (12) Å in the other. In the diphenyl­aniline units, the terminal phenyl rings are almost orthogonal to each other, with dihedral angles of 89.79 (9) and 89.76 (9)°. The crystal structure features C—H⋯O and C—H⋯π inter­actions.

{2-[(9,9-Dihexyl-fluoren-2-yl)carbon-yl]phen-yl}(4-meth-oxy-phen-yl)methanone

In the title compound, C₄₀H₄₄O₃, the fluorene ring system is essentially planar, with a maximum deviation of 0.075 (3) Å, and forms dihedral angles of 70.62 (8) and 70.31 (8)° with the mean planes of the central benzene ring and the meth­oxy­phenyl ring, respectively. Both the hexyl side chains have different conformations, i.e. an anti–gauche–anti–gauche conformation with C—C—C—C torsion angles of −169.3 (2), 74.2 (4), −178.0 (3) and −76.0 (6)° for one hexyl side chain and an anti–anti–anti–gauche conformation with C—C—C—C torsion angles of −177.9 (2), −176.5 (3), 171.7 (4) and 80.4 (9)° for the other. Four C atoms in one and two C atoms in the other hexyl side chains are each disordered over two sets of sites, with occupancy factors of 0.761 (3):0.239 (3) and 0.660 (6):0.340 (6). In the crystal, mol­ecules are via pairs of C—H⋯O hydrogen bonds, forming inversion dimers and resulting in R₂²(28) graph-set motifs.

5-Methoxy-3-[(5-methoxy-1H-indol-3-yl)(phenyl)methyl]-1H-indole

In the title compound, C₂₅H₂₂N₂O₂, the indole rings are individually almost planar [with maximum deviations of 0.0116 (19) and 0.0113 (18) Å] and are almost orthogonal to each other, making a dihedral angle of 84.49 (6)°. The benzene ring is inclined at 72.83 (9) and 80.85 (9)° with respect to the indole rings. In the crystal, mol­ecules are linked by N—H⋯O inter­actions into chains running parallel to the c axis. The crystal structure is further stabilized by C—H⋯π inter­actions.