CRISPR-induced exon skipping of ß-catenin reveals tumorigenic mutants driving distinct subtypes of liver cancer.

CRISPR/Cas9-driven cancer modeling studies are based on the disruption of tumor suppressor genes by small insertions or deletions (indels) that lead to frame-shift mutations. In addition, CRISPR/Cas9 is widely used to define the significance of cancer oncogenes and genetic dependencies in loss-of-function studies. However, how CRISPR/Cas9 influences gain-of-function oncogenic mutations is elusive. Here, we demonstrate that single guide RNA targeting exon 3 of Ctnnb1 (encoding ß-catenin) results in exon skipping and generates gain-of-function isoforms in vivo. CRISPR/Cas9-mediated exon skipping of Ctnnb1 induces liver tumor formation in synergy with YAPS127A in mice. We define two distinct exon skipping-induced tumor subtypes with different histological and transcriptional features. Notably, ectopic expression of two exon-skipped ß-catenin transcript isoforms together with YAPS127A phenocopies the two distinct subtypes of liver cancer. Moreover, we identify similar CTNNB1 exon-skipping events in patients with hepatocellular carcinoma. Collectively, our findings advance our understanding of ß-catenin-related tumorigenesis and reveal that CRISPR/Cas9 can be repurposed, in vivo, to study gain-of-function mutations of oncogenes in cancer. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

A 10-year systematic review and meta-analysis of determinants of postpartum depression in the Association of Southeast Asian Nations countries.

INTRODUCTION: Postpartum depression (PPD) is a mental and emotional condition that can affect women during their first postnatal year and concern globally. This study aimed to determine the overall prevalence and determinants of postpartum depression (PPD) in Association of Southeast Asian Nations (ASEAN) countries. MATERIALS AND METHODS: A systematic search of observational studies conducted in ASEAN countries between 1 January 2010 and 31 December 2020 was performed in the Medline, PubMed and Google Scholar databases. The quality of studies was evaluated based on The Joanna Briggs Institute Checklist. The analysis was performed with Review Manager software version 5.4. Metaanalysis of the estimates from primary studies was conducted by adjusting for possible publication bias and heterogeneity. RESULTS: Twenty-five studies including 19924 postnatal mothers were included in this review. The pooled prevalence of PPD is 22.32% (95% CI: 18.48, 26.17). Thailand has the highest prevalence of PPD with a pooled prevalence of 74.1% (95% CI: 64.79, 83.41). The prevalence of PPD was highest when the assessment for PPD was conducted up to 6 weeks postpartum with a pooled prevalence of 25.24% (95% CI: 14.08, 36.41). The identified determinants of PPD were unplanned pregnancy, term pregnancy, lack of family support and physical violence. There were limited studies done and high heterogeneity in terms of quality, methodology, culture, screening method and time of PPD measurement. CONCLUSIONS: Approximately one in five postpartum women in ASEAN countries had PPD. The risk factor that lowers the risk of PPD is unplanned and term pregnancies, while women with a lack of family support and experienced physical violence increase the risk of PPD. Robust prevalence studies are needed to assess the magnitude of this problem in ASEAN countries.

Development, validation, and evaluation of allergic rhinitis symptoms and impact assessment (ARSIA) questionnaire.

INTRODUCTION: Allergic rhinitis (AR) is an inflammatory disease of the nasal mucosa. It is among the most common diseases globally and usually persists throughout life. Allergic Rhinitis and Its Impact on Asthma (ARIA) is a wellestablished guideline applicable to AR and was updated regularly since 2001, aiming to improve the care for AR patients. We proposed a new questionnaire that addresses the severity of allergic rhinitis symptoms, specifically nasal symptoms, and its impact on quality of life in terms of specific vital activities such as sleeping, working, school performance, leisure, or sport, based on the ARIA guideline. The objective was to develop, validate and evaluate Allergic Rhinitis Symptoms and Impact Assessment (ARSIA) questionnaire among allergic rhinitis patients in Hospital Sultan Abdul Halim, Sungai Petani (HSAH), and Hospital Universiti Sains Malaysia (HUSM). MATERIALS AND METHODS: This is a prospective observational study to develop, validate and evaluate the ARSIA questionnaire based on ARIA guidelines. The sample will be obtained from the list of patients under follow-up in the ORL clinic HSAH and HUSM with ages of 18 to 60 years, patients clinically diagnosed with allergic rhinitis, and with positive skin prick test. RESULTS: A total of 150 patients with a positive skin prick test participated in this study. In the 'nasal symptom' and 'impact on daily activities' domains, calculated Cronbach's alpha shows a value of 0.878 and 0.811 respectively. The inter-item correlation was calculated to analyse internal consistency reliability. Items B3 and B4 were dropped from the questionnaire as both showed a low correlation with other items. New Cronbach's alpha for the daily activities domain was 0.830, which showed better internal consistency reliability. All of the items were analysed for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Clinician diagnosis from the proforma was used as a comparison to the participant's responses. In the analysis, a cut-off points of 12 was used to classify the patient's nasal symptoms into intermittent or persistent, with a sensitivity of 75%, specificity of 86%, PPV of 95%, and NPV of 51%. Whereas, a cut-off point of 15 was used to classify the rhinitis impact on daily activities into mild or moderate/severe, with a sensitivity of 58%, specificity of 100%, PPV of 100%, and NPV of 42%. The only item in the 'control' domain has been dropped out following a consensus of experts and judgement as it has not been used in the clinician diagnosis and thus, is unable to test for sensitivity, specificity, PPV, and NPV. CONCLUSION: This newly developed, validated, and evaluated questionnaire is a good tool for the evaluation of allergic rhinitis symptoms and their impact on daily activities. It is important to understand that AR symptoms could have a significant impact on daily activities. Although further study and testing are needed, it provides an initial means for evaluating the patient condition and control level, as well as patients' perception of their rhinitis control.

Cryo-EM structures of prion protein filaments from Gerstmann-Sträussler-Scheinker disease.

Prion protein (PrP) aggregation and formation of PrP amyloid (APrP) are central events in the pathogenesis of prion diseases. In the dominantly inherited prion protein amyloidosis known as Gerstmann-Sträussler-Scheinker (GSS) disease, plaques made of PrP amyloid are present throughout the brain. The c.593t > c mutation in the prion protein gene (PRNP) results in a phenylalanine to serine amino acid substitution at PrP residue 198 (F198S) and causes the most severe amyloidosis among GSS variants. It has been shown that neurodegeneration in this disease is associated with the presence of extracellular APrP plaques and neuronal intracytoplasmic Tau inclusions, that have been shown to contain paired helical filaments identical to those found in Alzheimer disease. Using cryogenic electron microscopy (cryo-EM), we determined for the first time the structures of filaments of human APrP, isolated post-mortem from the brain of two symptomatic PRNP F198S mutation carriers. We report that in GSS (F198S) APrP filaments are composed of dimeric, trimeric and tetrameric left-handed protofilaments with their protomers sharing a common protein fold. The protomers in the cross-ß spines consist of 62 amino acids and span from glycine 80 to phenylalanine 141, adopting a previously unseen spiral fold with a thicker outer layer and a thinner inner layer. Each protomer comprises nine short ß-strands, with the ß1 and ß8 strands, as well as the ß4 and ß9 strands, forming a steric zipper. The data obtained by cryo-EM provide insights into the structural complexity of the PrP filament in a dominantly inherited human PrP amyloidosis. The novel findings highlight the urgency of extending our knowledge of the filaments' structures that may underlie distinct clinical and pathologic phenotypes of human neurodegenerative diseases.

Interfaces with the peripheral nervous system for the control of a neuroprosthetic limb: a review.

The field of prosthetics has been evolving and advancing over the past decade, as patients with missing extremities are expecting to control their prostheses in as normal a way as possible. Scientists have attempted to satisfy this expectation by designing a connection between the nervous system of the patient and the prosthetic limb, creating the field of neuroprosthetics. In this paper, we broadly review the techniques used to bridge the patient's peripheral nervous system to a prosthetic limb. First, we describe the electrical methods including myoelectric systems, surgical innovations and the role of nerve electrodes. We then describe non-electrical methods used alone or in combination with electrical methods. Design concerns from an engineering point of view are explored, and novel improvements to obtain a more stable interface are described. Finally, a critique of the methods with respect to their long-term impacts is provided. In this review, nerve electrodes are found to be one of the most promising interfaces in the future for intuitive user control. Clinical trials with larger patient populations, and for longer periods of time for certain interfaces, will help to evaluate the clinical application of nerve electrodes.

Migrant children's health problems, care needs, and inequalities: European primary care paediatricians' perspective.

BACKGROUND: Primary care paediatricians' perception of migrant children's health in Europe has not been explored before. Our aim was to examine European paediatricians' knowledge on migrant children's health problems, needs, inequalities, and barriers to access health care. METHODS: European primary care paediatricians were invited by the European Academy of Paediatrics Research in Ambulatory Setting Network country coordinators to complete a web-based survey concerning health care of migrant children. A descriptive analysis of all variables was performed. RESULTS: The survey was completed by 492 paediatricians. Sixty-three per cent of the respondents reported that the general health of migrant children is worse than that of nonmigrants, chronic diseases cited by 66% of the respondents as the most frequent health problem. Sixty-six per cent of the paediatricians reported that migrant children have different health needs compared to nonmigrant children, proper oral health care mentioned by 86% of the respondents. Cultural/linguistic factors have been reported as the most frequent barrier (90%).to access health care. However, only 37% of providers have access to professional interpreters and cultural mediators. Fifty-two per cent and 32% do not know whether one or more of the family members are undocumented and whether they are refugees/asylum seekers, respectively. Updated guidelines for care of migrant children are available for only 35% of respondents, and 80% of them have not received specific training on migrant children's care. CONCLUSIONS: European primary care paediatricians recognize migrant children as a population at risk with more frequent and specific health problems and needs, but they are often unaware of their legal state. Lack of interpreters augments the existing language barriers to access proper care and should be solved. Widespread lack of guidelines and specific providers' training should be addressed to optimize health care delivery to migrant children.

Bending of the BST-2 coiled-coil during viral budding.

BST-2/tetherin is a human extracellular transmembrane protein that serves as a host defense factor against HIV-1 and other viruses by inhibiting viral spreading. Structurally, BST-2 is a homo-dimeric coiled-coil that is connected to the host cell membrane by N and C terminal transmembrane anchors. The C-terminal membrane anchor of BST-2 is inserted into the budding virus while the N-terminal membrane anchor remains in the host cell membrane creating a viral tether. The structural mechanism of viral budding and tethering as mediated by BST-2 is not clear. To more fully describe the mechanism of viral tethering, we created a model of BST-2 embedded in a membrane and used steered molecular dynamics to simulate the transition from the host cell membrane associated form to the cell-virus membrane bridging form. We observed that BST-2 did not transition as a rigid structure, but instead bent at positions with a reduced interface between the helices of the coiled-coil. The simulations for the human BST-2 were then compared with simulations on the mouse homolog, which has no apparent weak spots. We observed that the mouse homolog spread the bending across the ectodomain, rather than breaking at discrete points as observed with the human homolog. These simulations support previous biochemical and cellular work suggesting some flexibility in the coiled-coil is necessary for viral tethering, while also highlighting how subtle changes in protein sequence can influence the dynamics and stability of proteins with overall similar structure.

Waste bones ash as an alternative source of P for struvite precipitation.

Struvite precipitation has been widely applied for the removal of ammonium-nitrogen (NH4-N) from wastewater. Due to the high cost of phosphorus (P) reagents, the current research trend was directed to find alternative sources of P, in order to maintain a sustainable NH4-N removal process. The current study investigated waste bones ashes as alternative sources of P. Different types of bones' ashes were characterized, in which the ash produced from waste fish bones was the highest in P content (17%wt.). The optimization of the factors affecting P extraction from ash by acidic leaching showed that applying 2M H2SO4 and 1.25 kg H2SO4/kg ash achieved the highest P recovery (95%). Thereafter, the recovered P was successfully used in struvite precipitation, which achieved more than 90% NH4-N removal and high purity struvite.

Risk factors for suicidal ideation, plans and attempts in Malaysia--results of an epidemiological survey.

OBJECTIVE: This is an epidemiological study to determine the prevalence of suicidal behavior and its association with generalised anxiety disorder (GAD) and major depressive disorder (MDD) in a nationally representative sample. METHOD: Suicidal ideation, plans and attempts were assessed in face-to-face interviews of respondents selected by a multistage probability sampling using items on suicidality from the WHO SUPRE-MISS questionnaire. The Mini International Neuropsychiatric Interview (MINI) was used to generate DSM-IV diagnoses of GAD and MDD. A total of 19309 subjects were studied. Multivariate regression analysis was conducted controlling for demographic characteristics such as age, gender and ethnicity. RESULTS: The prevalence estimates for suicide ideation, plans and attempts were 1.7% (95% CI: 1.4-1.9), 0.9% (CI: 0.7-1.1) and 0.5% (CI: 0.4-0.7) respectively. Younger people (16-24 years) had higher risk of suicidal behavior (OR: 2.6, CI: 1.08-6.2). Females (OR: 1.6, CI: 1.2-2.1) and Indians (OR: 3.3, CI: 2.2-4.9) also had higher risk. CONCLUSION: The prevalence of suicidal behavior in Malaysia is low, but it broadly corresponds to the pattern described in other countries. This national study confirms that Malaysians of Indian descent have much higher rates of suicidal behavior than other groups. The younger age group, females and the Indian ethnic group would need focused preventive efforts.

Radiation recall dermatitis in HER 2 positive breast cancer patients triggered by trastuzumab: A rare case report and review of literature.

INTRODUCTION AND IMPORTANCE: Radiation recall dermatitis (RRD) is a localized drug-induced inflammatory skin reaction occurring exclusively in a previously irradiated site months to years after discontinuation of ionizing radiation. The symptoms of RRD can range from mild redness to extensive dermatitis. Antineoplastic drugs such as doxorubicin, docetaxel, paclitaxel, and gemcitabine are most commonly associated with radiation recall reactions. These reactions can also occur with antibiotics and anti-tubercular drugs. CASE PRESENTATION: A 38-years-old woman with hormone receptor-negative, HER2-positive inflammatory breast cancer (right), clinical stage cT4dN1Mx, received neoadjuvant chemotherapy with AC > TH protocol at 3 weeks intervals (Anthracycline-Doxorubicin plus Cyclophosphamide X 4 cycles, then docetaxel plus Trastuzumab X 4 cycles) followed by modified radical mastectomy followed by adjuvant locoregional radiotherapy. She received the 5th cycle and 6th cycle trastuzumab monotherapy just before the start of surgery and radiotherapy, respectively. After 1 month of completion of radiotherapy, during her seventh cycle of Trastuzumab monotherapy, she developed mild edema with erythematous change over the previously irradiated area with fever. A skin biopsy was taken to exclude any recurrence; however, no evidence of malignancy was found. CLINICAL DISCUSSION: We diagnosed it as a case of RRD. We managed her conservatively. Later, she was rechallenged with the same dose in subsequent cycles with systemic steroid coverage, which she tolerated very well, except for the reappearance of mild erythema following each cycle of maintenance dose of Trastuzumab. CONCLUSION: Radiation recall dermatitis is an extremely rare phenomenon; hence, an acquaintance of clinicians with this rare entity is essential for timely diagnosis and appropriate management.

Trastuzumab-induced toxic epidermal necrolysis in a Her-2-positive metastatic breast cancer patient-A rare case report.

Toxic Epidermal Necrolysis (TEN) is a rare, but potentially fatal mucocutaneous reaction, that may occur due to an immunologic response to certain medications. However, TEN triggered by Trastuzumab is extremely rare. Early diagnosis, recognition, and prompt cessation of the offending drugs and initiation of steroid therapy with supportive management are the most important actions for managing TEN. Although rare, it is important to be vigilant about this potential adverse reactions associated with trastuzumab to ensure patient safety and contribute to better outcomes.

Cryo-EM structures of amyloid-ß and tau filaments in Down syndrome.

Adult individuals with Down syndrome (DS) develop Alzheimer disease (AD). Whether there is a difference between AD in DS and AD regarding the structure of amyloid-ß (Aß) and tau filaments is unknown. Here we report the structure of Aß and tau filaments from two DS brains. We found two Aß40 filaments (types IIIa and IIIb) that differ from those previously reported in sporadic AD and two types of Aß42 filaments (I and II) identical to those found in sporadic and familial AD. Tau filaments (paired helical filaments and straight filaments) were identical to those in AD, supporting the notion of a common mechanism through which amyloids trigger aggregation of tau. This knowledge is important for understanding AD in DS and assessing whether adults with DS could be included in AD clinical trials.

Suicide prevention program for at-risk groups: pointers from an epidemiological study.

OBJECTIVES: The aim of this paper is to identify at-risk groups for a focused suicide prevention program for Malaysia. METHODS: Data from 20,552 persons aged 16 years and above (males 45.9%), was obtained using stratified, random sampling in a national survey of psychiatric morbidity using locally validated General Health Questionnaire (GHQ-28) which included questions on suicidal ideation. RESULTS: The overall prevalence of suicidal ideation (SI) was 6.3%, CI 6.1-6.8 (n=1288). Logistic regression analysis was performed with age, ethnicity, gender, urban/rural residence, age group, marital status, household income, type of household, presence of chronic pain, social dysfunction, somatic, anxiety or depressive symptoms, obesity, and chronic medical illnesses as independent variables. Only Insomnia, Religion, Marital Status, Depression, Social Dysfunction and Anxiety were seen to be significant predictors. Prevalence of SI was significantly higher among Indians (11.0%, CI 9.5-12.5), especially those of the Hindu faith (12.2%, CI 10.5-14.0), Chinese (9.7%, CI 8.8-10.7) and those having depressive symptoms. CONCLUSION: In a developing country with competing priorities, prudent allocation of resources requires focusing suicide prevention efforts on treating depression in vulnerable groups.

Serotonin distinctly controls behavioral states in restrained and freely moving Drosophila.

When trapped in a physical restraint, animals must select an escape strategy to increase their chances of survival. After falling into an inescapable trap, they react with stereotypical behaviors that differ from those displayed in escapable situations. Such behaviors involve either a wriggling response to unlock the trap or feigning death to fend off a predator attack. The neural mechanisms that regulate animal behaviors have been well characterized for escapable situations but not for inescapable traps. We report that restrained vinegar flies exhibit alternating flailing and immobility to free themselves from the trap. We used optogenetics and intersectional genetic approaches to show that, while broader serotonin activation promotes immobility, serotonergic cells in the ventral nerve cord (VNC) regulate immobility states majorly via 5-HT7 receptors. Restrained and freely moving locomotor states are controlled by distinct mechanisms. Taken together, our study has identified serotonergic switches of the VNC that promote environment-specific adaptive behaviors.

Cross-ß helical filaments of Tau and TMEM106B in Gray and White Matter of Multiple System Tauopathy with presenile Dementia.

Background: The Microtubule-Associated Protein Tau (MAPT) is one of the proteins that are central to neurodegenerative diseases. The nature of intracellular tau aggregates is determined by the cell types whether neuronal or glial, the participating tau isoforms, and the structure of the amyloid filament. The transmembrane protein 106B (TMEM106B) has recently emerged as another significant player in neurodegeneration and aging. In the central nervous system, the composition of the gray and white matter differs considerably. The gray matter consists of nerve cell bodies, dendrites, unmyelinated axons, synaptic terminals, astrocytes, oligodendrocytes (satellite cells) and microglia. The white matter differs from the gray for the presence of axonal tracts as the only neuronal component and for the absence of nerve cell bodies, dendrites and synaptic terminals. Cryogenic electron microscopy (cryo-EM) studies have unveiled the structure of tau and TMEM106B, from the cerebral cortex, in several neurodegenerative diseases; however, whether tau and TMEM106B filaments from the gray and white matter share a common fold requires additional investigation. Methods: We isolated tau and TMEM106B from the cerebral cortex and white matter of the frontal lobes of two individuals affected by multiple system tauopathy with presenile dementia (MSTD), a disease caused by the MAPT intron 10 mutation +3. We used immunostaining, biochemical, genetics and cryo-EM methods to characterize tau and TMEM106B. Results: We determined that tau filaments in the gray and the white matter of MSTD individuals can induce tau aggregation and have identical AGD type 2 folds. TMEM106B amyloid filaments were also found in the gray and white matter of MSTD; the filament folds were identical in the two anatomical regions. Conclusions: Our findings show for the first time that in MSTD two types of amyloid filaments extracted from the gray matter have identical folds to those extracted from the white matter. Whether in this genetic disorder there is a relationship in the pathogenesis of the tau and TMEM106B filaments, remains to be determined. Furthermore, additional studies are needed for other proteins and other neurodegenerative diseases to establish whether filaments extracted from the gray and white matter would have identical folds.

Surveillance and genotype characterization of zoonotic trypanosomatidae in Didelphis marsupialis in two endemic sites of rural Panama.

Didelphis marsupialis has been reported as a competent reservoir for trypanosomatid parasites infections. The aim of this study was to measure Trypanosoma cruzi, T. rangeli, and Leishmania spp. infection rates and to characterize discrete typing units (DTUs) of T. cruzi in D. marsupialis from two Chagas disease endemic sites in Panama. Blood from 57 wild-caught D. marsupialis were examined from two rural communities, Las Pavas (N = 18) and Trinidad de las Minas (N = 39). Twenty-two (38.60%) opossums were positive for flagellates by general hemoculture. T. cruzi infection was confirmed by positive hemoculture and/or kDNA based PCR performed in 31/57 (54.39%) blood samples from opossums. T. rangeli infection was confirmed by hemoculture and/or TrF/R2-Primer PCR assay applied on 12/57 (21.05%) blood samples. Nine (15.79%) D. marsupialis harbored T. cruzi/T. rangeli coinfections. All opossums tested negative for Leishmania spp. by PCR assays based on kDNA and HSP70 gene amplification. There was a significant association between T. cruzi infection and site (Fisher exact test, p = 0.02), with a higher proportion of T. cruzi infected opossums in Las Pavas (77.78%, n = 14/18) compared to Trinidad de las Minas (43.59%, n = 17/39). A significant association was found between habitat type and T. cruzi infection in opossums across both communities, (X2 = 6.91, p = 0.01, df = 1), with a higher proportion of T. cruzi infection in opossums captured in forest remnants (76%, 19/25) compared to peridomestic areas (37.5%, 12/32). T. rangeli detection, but not T. cruzi detection, may be improved by culture followed by PCR. TcI was the only DTU detected in 22 T. cruzi samples using conventional and real-time PCR. Eight T. rangeli positive samples were characterized as KP1(-)/lineage C. Trypanosome infection data from this common synanthropic mammal provides important information for improved surveillance and management of Chagas disease in endemic regions of Panama.

Numerical study of nano-biofilm stagnation flow from a nonlinear stretching/shrinking surface with variable nanofluid and bioconvection transport properties.

A mathematical model is developed for stagnation point flow toward a stretching or shrinking sheet of liquid nano-biofilm containing spherical nano-particles and bioconvecting gyrotactic micro-organisms. Variable transport properties of the liquid (viscosity, thermal conductivity, nano-particle species diffusivity) and micro-organisms (species diffusivity) are considered. Buongiorno's two-component nanoscale model is deployed and spherical nanoparticles in a dilute nanofluid considered. Using a similarity transformation, the nonlinear systems of partial differential equations is converted into nonlinear ordinary differential equations. These resulting equations are solved numerically using a central space finite difference method in the CodeBlocks Fortran platform. Graphical plots for the distribution of reduced skin friction coefficient, reduced Nusselt number, reduced Sherwood number and the reduced local density of the motile microorganisms as well as the velocity, temperature, nanoparticle volume fraction and the density of motile microorganisms are presented for the influence of wall velocity power-law index (m), viscosity parameter [Formula: see text], thermal conductivity parameter (c4), nano-particle mass diffusivity (c6), micro-organism species diffusivity (c8), thermophoresis parameter [Formula: see text], Brownian motion parameter [Formula: see text], Lewis number [Formula: see text], bioconvection Schmidt number [Formula: see text], bioconvection constant (σ) and bioconvection Péclet number [Formula: see text]. Validation of the solutions via comparison related to previous simpler models is included. Further verification of the general model is conducted with the Adomian decomposition method (ADM). Extensive interpretation of the physics is included. Skin friction is elevated with viscosity parameter ([Formula: see text] whereas it is suppressed with greater Lewis number and thermophoresis parameter. Temperatures are elevated with increasing thermal conductivity parameter ([Formula: see text] whereas Nusselt numbers are reduced. Nano-particle volume fraction (concentration) is enhanced with increasing nano-particle mass diffusivity parameter ([Formula: see text]) whereas it is markedly reduced with greater Lewis number (Le) and Brownian motion parameter (Nb). With increasing stretching/shrinking velocity power-law exponent ([Formula: see text] skin friction is decreased whereas Nusselt number and Sherwood number are both elevated. Motile microorganism density is boosted strongly with increasing micro-organism diffusivity parameter ([Formula: see text]) and Brownian motion parameter (Nb) but reduced considerably with greater bioconvection Schmidt number (Sc) and bioconvection Péclet number (Pe). The simulations find applications in deposition processes in nano-bio-coating manufacturing processes.

The effects of molecular crowding and CpG hypermethylation on DNA G-quadruplexes formed by the C9orf72 nucleotide repeat expansion.

A nucleotide repeat expansion (NRE), (G4C2)n, located in a classically noncoding region of C9orf72 (C9), is the most common genetic mutation associated with ALS/FTD. There is increasing evidence that nucleic acid structures formed by the C9-NRE may both contribute to ALS/FTD, and serve as therapeutic targets, but there is limited characterization of these nucleic acid structures under physiologically and disease relevant conditions. Here we show in vitro that the C9-NRE DNA can form both parallel and antiparallel DNA G-quadruplex (GQ) topological structures and that the structural preference of these DNA GQs can be dependent on the molecular crowding conditions. Additionally, 5-methylcytosine DNA hypermethylation, which is observed in the C9-NRE locus in some patients, has minimal effects on GQ topological preferences. Finally, molecular dynamic simulations of methylated and nonmethylated GQ structures support in vitro data showing that DNA GQ structures formed by the C9-NRE DNA are stable, with structural fluctuations limited to the cytosine-containing loop regions. These findings provide new insight into the structural polymorphic preferences and stability of DNA GQs formed by the C9-NRE in both the methylated and nonmethylated states, as well as reveal important features to guide the development of upstream therapeutic approaches to potentially attenuate C9-NRE-linked diseases.

Molecular Identification of Parasites Causing Cutaneous Leishmaniasis in Panama.

Isolates from 475 cutaneous leishmaniasis (CL) patients from three endemic regions were studied by three typing techniques. The molecular analysis from lesion scrapings based on hsp70 PCR-restriction fragment length polymorphism (RFLP) showed that 78.1% (371/475) restriction patterns corresponded to Leishmania (Viannia) panamensis, 19% (90/475) to Leishmania (Viannia) guyanensis, and 3.0% (14/475) to Leishmania (Viannia) braziliensis. Promastigotes isolated by culture from lesions of 228 patients (48.0%, 228/475) were identified by multi-locus enzyme electrophoresis. Of them, 95.2% (217/228) were typified as L. (V.) panamensis, 1.3% (3/228) as L. (V.) guyanensis, 2.2% (5/228) as L. (V.) braziliensis, and 1.3% (3/228) as hybrids (L. [V.] braziliensis/L. [V.] panamensis). However, a partial sequencing analysis of the hsp70 gene from 77 selected samples showed 16.9% (13/77) typified as L. (V.) panamensis, 68.8% (53/77) as Leishmania (V.) sp., 1, 3.9% (3/77) as L. (V.) guyanensis, 1.3% (1/77) as L. (V.) braziliensis outlier, 2.6% (2/77) as Leishmania (Viannia) naiffi, 2.6% as (2/77) Leishmania (V.) sp., and 2 and 3.9% (3/77) hybrid isolates of L. (V.) braziliensis/L. (V.) guyanensis. These results confirm L. (V.) panamensis as the predominant species and cause of CL lesions in Panama and that L. (V.) guyanensis, L. (V.) braziliensis, and L. (V.) naiffi are circulating to a lower degree. Furthermore, the determination of parasite isolates belonging to atypical clusters and hybrid isolates suggests the circulation of genetic variants with important implications for the epidemiology and clinical follow-up of CL in Panama. No evidence of the existence of parasites of the Leishmania (Leishmania) mexicana complex in Panamanian territory was found in this study.