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1.
PLoS Negl Trop Dis ; 18(6): e0011836, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38857289

ABSTRACT

The geographical range of schistosomiasis is affected by the ecology of schistosome parasites and their obligate host snails, including their response to temperature. Previous models predicted schistosomiasis' thermal optimum at 21.7°C, which is not compatible with the temperature in sub-Saharan Africa (SSA) regions where schistosomiasis is hyperendemic. We performed an extensive literature search for empirical data on the effect of temperature on physiological and epidemiological parameters regulating the free-living stages of S. mansoni and S. haematobium and their obligate host snails, i.e., Biomphalaria spp. and Bulinus spp., respectively. We derived nonlinear thermal responses fitted on these data to parameterize a mechanistic, process-based model of schistosomiasis. We then re-cast the basic reproduction number and the prevalence of schistosome infection as functions of temperature. We found that the thermal optima for transmission of S. mansoni and S. haematobium range between 23.1-27.3°C and 23.6-27.9°C (95% CI) respectively. We also found that the thermal optimum shifts toward higher temperatures as the human water contact rate increases with temperature. Our findings align with an extensive dataset of schistosomiasis prevalence in SSA. The refined nonlinear thermal-response model developed here suggests a more suitable current climate and a greater risk of increased transmission with future warming for more than half of the schistosomiasis suitable regions with mean annual temperature below the thermal optimum.


Subject(s)
Schistosoma haematobium , Schistosoma mansoni , Temperature , Animals , Humans , Schistosoma haematobium/physiology , Schistosoma mansoni/physiology , Africa South of the Sahara/epidemiology , Biomphalaria/parasitology , Schistosomiasis/transmission , Schistosomiasis/epidemiology , Schistosomiasis mansoni/transmission , Schistosomiasis mansoni/epidemiology , Bulinus/parasitology , Schistosomiasis haematobia/transmission , Schistosomiasis haematobia/epidemiology , Prevalence
2.
medRxiv ; 2024 May 21.
Article in English | MEDLINE | ID: mdl-38826336

ABSTRACT

The geographical range of schistosomiasis is affected by the ecology of schistosome parasites and their obligate host snails, including their response to temperature. Previous models predicted schistosomiasis' thermal optimum at 21.7 °C, which is not compatible with the temperature in sub-Saharan Africa (SSA) regions where schistosomiasis is hyperendemic. We performed an extensive literature search for empirical data on the effect of temperature on physiological and epidemiological parameters regulating the free-living stages of S. mansoni and S. haematobium and their obligate host snails, i.e., Biomphalaria spp. and Bulinus spp., respectively. We derived nonlinear thermal responses fitted on these data to parameterize a mechanistic, process-based model of schistosomiasis. We then re-cast the basic reproduction number and the prevalence of schistosome infection as functions of temperature. We found that the thermal optima for transmission of S. mansoni and S. haematobium range between 23.1-27.3 °C and 23.6-27.9 °C (95 % CI) respectively. We also found that the thermal optimum shifts toward higher temperatures as the human water contact rate increases with temperature. Our findings align with an extensive dataset of schistosomiasis prevalence in SSA. The refined nonlinear thermal-response model developed here suggests a more suitable current climate and a greater risk of increased transmission with future warming for more than half of the schistosomiasis suitable regions with mean annual temperature below the thermal optimum.

3.
PLoS One ; 18(9): e0290615, 2023.
Article in English | MEDLINE | ID: mdl-37703262

ABSTRACT

The human burden of environmentally transmitted infectious diseases can depend strongly on ecological factors, including the presence or absence of natural enemies. The marbled crayfish (Procambarus virginalis) is a novel invasive species that can tolerate a wide range of ecological conditions and colonize diverse habitats. Marbled crayfish first appeared in Madagascar in 2005 and quickly spread across the country, overlapping with the distribution of freshwater snails that serve as the intermediate host of schistosomiasis-a parasitic disease of poverty with human prevalence ranging up to 94% in Madagascar. It has been hypothesized that the marbled crayfish may serve as a predator of schistosome-competent snails in areas where native predators cannot and yet no systematic study to date has been conducted to estimate its predation rate on snails. Here, we experimentally assessed marbled crayfish consumption of uninfected and infected schistosome-competent snails (Biomphalaria glabrata and Bulinus truncatus) across a range of temperatures, reflective of the habitat range of the marbled crayfish in Madagascar. We found that the relationship between crayfish consumption and temperature is unimodal with a peak at ~27.5°C. Per-capita consumption increased with body size and was not affected either by snail species or their infectious status. We detected a possible satiation effect, i.e., a small but significant reduction in per-capita consumption rate over the 72-hour duration of the predation experiment. Our results suggest that ecological parameters, such as temperature and crayfish weight, influence rates of consumption and, in turn, the potential impact of the marbled crayfish invasion on snail host populations.


Subject(s)
Biomphalaria , Schistosomatidae , Humans , Animals , Astacoidea , Temperature , Predatory Behavior , Schistosoma
4.
Front Neurosci ; 17: 1197409, 2023.
Article in English | MEDLINE | ID: mdl-37378010

ABSTRACT

Functional seizures, a primary subtype of functional neurological disorder (FND), are a known cause of serious neurological disability with an increasing awareness of their impact amongst the neuroscience community. Situated at the intersection of neurology and psychiatry, FND is characterized by a range of alterations in motor, sensory or cognitive performance, such as abnormal movements, limb weakness, and dissociative, seizure-like episodes. Functional seizures are known, in part, to have psychological underpinnings; however, the lack of effective and consistent treatment options requires research and novel approaches to better understand the etiology, diagnosis and what constitutes a successful intervention. Ketamine, a selective blocker of the N-methyl-D-aspartate receptor, has a well-established safety and efficacy profile. In recent years, ketamine-assisted therapy has shown increasing potential for treating a broad range of psychiatric conditions, building on its demonstrated rapid-acting antidepressant effects. Here we present a 51-year-old female with refractory daily functional seizures leading to significant disability and a medical history significant for major depressive disorder (MDD) and posttraumatic stress disorder (PTSD). After unsuccessful treatment attempts, the patient underwent a novel protocol with ketamine-assisted therapy. After 3 weeks of ketamine-assisted therapy followed by 20 weeks of intermittent ketamine treatment and ongoing integrative psychotherapy, the patient's seizures were significantly reduced in frequency and severity. She experienced significant improvements in depressive symptoms and functional ability scores. To our knowledge, this is the first reported case describing improvement in functional seizures following ketamine-assisted therapy. While rigorous studies are needed, this case report encourages further investigation of ketamine-assisted therapy for functional seizures and other functional neurological symptoms.

6.
BMC Genomics ; 21(1): 723, 2020 Oct 19.
Article in English | MEDLINE | ID: mdl-33076839

ABSTRACT

BACKGROUND: Protein expression patterns underlie physiological processes and phenotypic differences including those occurring during early development. The Pacific oyster (Crassostrea gigas) undergoes a major phenotypic change in early development from free-swimming larval form to sessile benthic dweller while proliferating in environments with broad temperature ranges. Despite the economic and ecological importance of the species, physiological processes occurring throughout metamorphosis and the impact of temperature on these processes have not yet been mapped out. RESULTS: Towards this, we comprehensively characterized protein abundance patterns for 7978 proteins throughout metamorphosis in the Pacific oyster at different temperature regimes. We used a multi-statistical approach including principal component analysis, ANOVA-simultaneous component analysis, and hierarchical clustering coupled with functional enrichment analysis to characterize these data. We identified distinct sets of proteins with time-dependent abundances generally not affected by temperature. Over 12 days, adhesion and calcification related proteins acutely decreased, organogenesis and extracellular matrix related proteins gradually decreased, proteins related to signaling showed sinusoidal abundance patterns, and proteins related to metabolic and growth processes gradually increased. Contrastingly, different sets of proteins showed temperature-dependent abundance patterns with proteins related to immune response showing lower abundance and catabolic pro-growth processes showing higher abundance in animals reared at 29 °C relative to 23 °C. CONCLUSION: Although time was a stronger driver than temperature of metamorphic proteome changes, temperature-induced proteome differences led to pro-growth physiology corresponding to larger oyster size at 29 °C, and to altered specific metamorphic processes and possible pathogen presence at 23 °C. These findings offer high resolution insight into why oysters may experience high mortality rates during this life transition in both field and culture settings. The proteome resource generated by this study provides data-driven guidance for future work on developmental changes in molluscs. Furthermore, the analytical approach taken here provides a foundation for effective shotgun proteomic analyses across a variety of taxa.


Subject(s)
Crassostrea , Proteomics , Animals , Crassostrea/genetics , Gene Expression Profiling , Proteome , Temperature
7.
Clin Cancer Res ; 26(16): 4349-4359, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32439698

ABSTRACT

PURPOSE: Radiation and cetuximab are therapeutics used in management of head and neck squamous cell carcinoma (HNSCC). Despite clinical success with these modalities, development of both intrinsic and acquired resistance is an emerging problem in the management of this disease. The purpose of this study was to investigate signaling of the receptor tyrosine kinase AXL in resistance to radiation and cetuximab treatment. EXPERIMENTAL DESIGN: To study AXL signaling in the context of treatment-resistant HNSCC, we used patient-derived xenografts (PDXs) implanted into mice and evaluated the tumor response to AXL inhibition in combination with cetuximab or radiation treatment. To identify molecular mechanisms of how AXL signaling leads to resistance, three tyrosine residues of AXL (Y779, Y821, Y866) were mutated and examined for their sensitivity to cetuximab and/or radiation. Furthermore, reverse phase protein array (RPPA) was employed to analyze the proteomic architecture of signaling pathways in these genetically altered cell lines. RESULTS: Treatment of cetuximab- and radiation-resistant PDXs with AXL inhibitor R428 was sufficient to overcome resistance. RPPA analysis revealed that such resistance emanates from signaling of tyrosine 821 of AXL via the tyrosine kinase c-ABL. In addition, inhibition of c-ABL signaling resensitized cells and tumors to cetuximab or radiotherapy even leading to complete tumor regression without recurrence in head and neck cancer models. CONCLUSIONS: Collectively, the studies presented herein suggest that tyrosine 821 of AXL mediates resistance to cetuximab by activation of c-ABL kinase in HNSCC and that targeting of both EGFR and c-ABL leads to a robust antitumor response.


Subject(s)
Cetuximab/pharmacology , Genes, abl/genetics , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/radiotherapy , Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases/genetics , Animals , Cell Line, Tumor , Cetuximab/adverse effects , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/radiation effects , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Humans , Mice , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/radiotherapy , Proteomics , Radiation Tolerance/genetics , Signal Transduction/drug effects , Signal Transduction/radiation effects , Tyrosine/genetics , Xenograft Model Antitumor Assays , Axl Receptor Tyrosine Kinase
8.
Female Pelvic Med Reconstr Surg ; 20(2): 111-2, 2014.
Article in English | MEDLINE | ID: mdl-24566216

ABSTRACT

This is the case of a 45-year-old woman with a history of asthma and smoking who developed complete left lung and right upper lobe collapse secondary to mucus plugs that developed immediately postoperatively after an uncomplicated reconstructive pelvic surgery. This rare intraoperative complication was successfully treated in the recovery room with bedside fiber-optic bronchoscopy. This resulted in complete resolution of her pulmonary findings within 24 hours of bronchoscopy.


Subject(s)
Gynecologic Surgical Procedures/adverse effects , Intraoperative Complications/etiology , Mucus , Pelvic Organ Prolapse/surgery , Plastic Surgery Procedures/adverse effects , Pulmonary Atelectasis/etiology , Bronchoscopy/methods , Female , Humans , Middle Aged
9.
Female Pelvic Med Reconstr Surg ; 19(3): 181-3, 2013.
Article in English | MEDLINE | ID: mdl-23611939

ABSTRACT

BACKGROUND: Labial adhesions are most commonly described in prepubertal girls. Only a few cases have been reported in postmenopausal women presenting with incomplete voiding. CASE: This report describes a case of a 51-year-old postmenopausal woman who presented with incomplete voiding and urinary incontinence. On examination, she had complete labial fusion and intraoperative findings of distal vaginal stenosis due to a constriction band. The patient was surgically treated with lysis of the labial fusion, posterior vaginal advancement flap with complete resolution of her urinary symptoms. CONCLUSION: In this report, we present a case of a postmenopausal patient with complete labial fusion, distal vaginal stenosis, and incomplete voiding who underwent successful surgical management with good anatomical results and complete resolution of urinary symptoms.


Subject(s)
Abnormalities, Multiple , Urinary Retention/etiology , Vagina/abnormalities , Vulva/abnormalities , Female , Humans , Middle Aged
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