Publications by authors named "Nagi S"

To keep ahead of the evolution of resistance to insecticides in mosquitoes, national malaria control programmes must make use of a range of insecticides, both old and new, while monitoring resistance mechanisms. The outdoor-biting malaria vector Anopheles arabiensis is of increasing concern for malaria transmission because it is apparently less susceptible to many indoor control interventions, yet knowledge of its mechanisms of resistance remains limited. Furthermore, comparatively little is known in general about resistance to non-pyrethroid insecticides such as pirimiphos-methyl (PM), which are crucial for effective control in the context of globally high resistance to pyrethroids.

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Article Synopsis
  • FA2 tactile afferents, associated with Pacinian corpuscles, are specialized for detecting high-frequency vibrations, unlike other afferents that focus on lower frequencies.
  • In this study, researchers used methods to block local tactile input and tested how well FA2 afferents could still perceive flutter-range frequencies (~20 Hz) on different skin types.
  • Findings showed that even when local receptors were blocked, the perception of flutter-range frequencies remained consistent, indicating that FA2-PC systems can encode this type of frequency without relying on inputs from low-frequency receptors.
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The versatility of somatosensation arises from heterogeneous dorsal root ganglion (DRG) neurons. However, soma transcriptomes of individual human (h)DRG neurons-critical information to decipher their functions-are lacking due to technical difficulties. In this study, we isolated somata from individual hDRG neurons and conducted deep RNA sequencing (RNA-seq) to detect, on average, over 9,000 unique genes per neuron, and we identified 16 neuronal types.

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Background: POLIII-related leukodystrophies are a group of recently recognized hereditary white matter diseases with a similar clinical and radiological phenotype. No Tunisian studies have been published about POLIII-related leukodystrophy due to POLR3A variants. The aim of this study was to contribute to the clinical, radiological, and genetic characterization of POLR3A-related leukodystrophy in a Tunisian cohort.

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A major insecticide resistance mechanism in insect pests is knock-down resistance (kdr) caused by mutations in the voltage-gated sodium channel (Vgsc) gene. Despite being common in most malaria Anopheles vector species, kdr mutations have never been observed in Anopheles funestus, the principal malaria vector in Eastern and Southern Africa, with resistance mainly being conferred by detoxification enzymes. In a parallel study, we monitored 10 populations of An.

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Malaria control relies on insecticides targeting the mosquito vector, but this is increasingly compromised by insecticide resistance, which can be achieved by elevated expression of detoxifying enzymes that metabolize the insecticide. In diploid organisms, gene expression is regulated both in , by regulatory sequences on the same chromosome, and by acting factors, affecting both alleles equally. Differing levels of transcription can be caused by mutations in -regulatory modules (CRM), but few of these have been identified in mosquitoes.

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Schistosomiasis, caused by trematodes of genus Schistosoma, is among the most seriously neglected tropical diseases. Although rapid surveillance of risk areas for Schistosoma transmission is vital to control schistosomiasis, the habitat and infection status of this parasite are difficult to assess. Environmental DNA (eDNA) analysis, involving the detection of extra-organismal DNA in water samples, facilitates cost-efficient and sensitive biomonitoring of aquatic environments and is a promising tool to identify Schistosoma habitat and infection risk areas.

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Cranial retained surgical sponges, known as "gossypiboma" or "textiloma", represent a rare but potentially severe complication following surgical procedures. While it is infrequent, it poses a significant risk, particularly in delicate surgical settings such as neurosurgery. The inadvertent retention of cotton balls or surgical gauzes may cause localized inflammation, infection, abscess, or neurologic sequelae.

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The major malaria mosquitoes, and , are some of the most studied organisms in medical research and also some of the most genetically diverse. When designing polymerase chain reaction (PCR) or hybridisation-based molecular assays, reliable primer and probe design is crucial. However, single nucleotide polymorphisms (SNPs) in primer binding sites can prevent primer binding, leading to null alleles, or bind suboptimally, leading to preferential amplification of specific alleles.

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The nociceptive withdrawal reflex (NWR) is a protective limb withdrawal response triggered by painful stimuli, used to assess spinal nociceptive excitability. Conventionally, the NWR is understood as having two reflex responses: a short-latency Aβ-mediated response, considered tactile, and a longer-latency Aδ-mediated response, considered nociceptive. However, nociceptors with conduction velocities similar to Aβ tactile afferents have been identified in human skin.

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The primary control methods for the African malaria mosquito, Anopheles gambiae, are based on insecticidal interventions. Emerging resistance to these compounds is therefore of major concern to malaria control programs. The organophosphate (OP), pirimiphos-methyl, is a relatively new chemical in the vector control armory but is now widely used in indoor-residual spray campaigns.

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A major mechanism of insecticide resistance in insect pests is knock-down resistance () caused by mutations in the voltage-gated sodium channel () gene. Despite being common in most malaria vector species, mutations have never been observed in , the principal malaria vector in Eastern and Southern Africa. While monitoring 10 populations of in Tanzania, we unexpectedly found resistance to DDT, a banned insecticide, in one location.

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Aim Of The Study: Biliary atresia (BA) is an important cause of surgical jaundice. Although the precise etiology is unknown, β-amyloid (Aβ) has been observed around the bile ducts in BA livers. It is unclear whether Aβ plays a role in the pathogenesis of this disease.

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Aim Of The Study: To investigate whether serum ferritin and vitamin D levels before starting autoimmune hepatitis (AIH) treatment have a role in disease prognosis regarding a therapeutic response.

Material And Methods: The prospective study included 100 children diagnosed with AIH according to simplified criteria for diagnosis of AIH. They attended the Pediatric Hepatology Department, National Liver Institute, Menoufia University.

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Background: Community and individual participation are crucial for the success of schistosomiasis control. The World Health Organization (WHO) has highlighted the importance of enhanced sanitation, health education, and Mass Drug Administration (MDA) in the fight against schistosomiasis. These approaches rely on the knowledge and practices of the community to be successful; however, where the community knowledge is low and inappropriate, it hinders intervention efforts.

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One hundred years ago, Erlanger and Gasser demonstrated that conduction velocity is correlated with the diameter of a peripheral nerve axon. Later, they also demonstrated that the functional role of the axon is related to its diameter: touch is signalled by large-diameter axons, whereas pain and temperature are signalled by small-diameter axons. Certain discoveries in recent decades prompt a modification of this canonical classification.

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To keep ahead of the evolution of resistance to insecticides in mosquitoes, national malaria control programmes must make use of a range of insecticides, both old and new, while monitoring resistance mechanisms. Knowledge of the mechanisms of resistance remains limited in , which in many parts of Africa is of increasing importance because it is apparently less susceptible to many indoor control interventions. Furthermore, comparatively little is known in general about resistance to non-pyrethroid insecticides such as pirimiphos-methyl (PM), which are crucial for effective control in the context of resistance to pyrethroids.

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Purpose: Migrants may have elevated exposure to stressors, which can affect their physical and mental well-being. However, migrants often experience a healthy immigrant effect, the applicability of this phenomena to eating disorders is unknown. We aimed to synthesize the available literature and estimate a summary measure of prevalence odds ratio for eating disorders in migrant populations compared to local populations.

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Molecular mechanisms driving the escalation of pyrethroid resistance in the major malaria mosquitoes of Central Africa remain largely uncharacterized, hindering effective management strategies. Here, resistance intensity and the molecular mechanisms driving it were investigated in a population of from northern Cameroon. High levels of pyrethroid and organochloride resistance were observed in population, with no mortality for 1× permethrin; only 11% and 33% mortalities for 5× and 10× permethrin diagnostic concentrations, and <2% mortalities for deltamethrin and DDT, respectively.

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Malaria control faces challenges from widespread insecticide resistance in major species. This study, employing a cross-species approach, integrates RNA-Sequencing, whole-genome sequencing, and microarray data to elucidate drivers of insecticide resistance in complex and Findings show an inverse relationship between genetic diversity and gene expression, with highly expressed genes experiencing stronger purifying selection. These genes cluster physically in the genome, revealing potential coordinated regulation.

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Article Synopsis
  • The primary method for controlling malaria mosquitoes relies on insecticides, but rising resistance to these chemicals poses a challenge for malaria control efforts.
  • Researchers studied the organophosphate insecticide pirimiphos-methyl and discovered new resistance mechanisms in mosquito populations, linked to detoxification enzymes.
  • Their findings indicate a parallel evolution for resistance traits, particularly a specific copy number variant in a gene associated with resistance, which has significant implications for future malaria control strategies.
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Tactile discrimination has been extensively studied, but mechanical pain discrimination remains poorly characterized. Here, we measured the capacity for mechanical pain discrimination using a two-alternative forced choice paradigm, with force-calibrated indentation stimuli (Semmes-Weinstein monofilaments) applied to the hand and foot dorsa of healthy human volunteers. In order to characterize the relationship between peripheral nociceptor activity and pain perception, we recorded single-unit activity from myelinated (A) and unmyelinated (C) mechanosensitive nociceptors in the skin using microneurography.

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  • Healthy eating is crucial for bolstering nutrition and immunity, and a study in western Kenya explored its link to stunting in school-aged children in a region where infectious diseases are common.
  • Involving 260 children aged 9-17, researchers used food frequency questionnaires and anthropometric measurements to assess diet quality and stunting, while also factoring in school attendance, household wealth, and infections like Schistosoma mansoni.
  • Results showed that 15% of children were stunted and 76.2% were infected with S. mansoni, with better diet quality correlated with lower stunting risk, particularly in those with light or no infections.
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