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31.
Mayaro virus (MAYV) is an emerging mosquito-borne arbovirus and public health concern. We evaluated the influence of temperature on Aedes aegypti responses to MAYV oral infection and transmission at two constant temperatures (20 °C and 30 °C). Infection of mosquito tissues (bodies and legs) and salivary secretions with MAYV was determined at 3, 9, 15, 21, and 27 days post ingestion. At both temperatures, we observed a trend of increase in progression of MAYV infection and replication kinetics over time, followed by a decline during later periods. Peaks of MAYV infection, titer, and dissemination from the midgut were detected at 15 and 21 days post ingestion at 30 °C and 20 °C, respectively. Mosquitoes were able to transmit MAYV as early as day 3 at 30 °C, but MAYV was not detectable in salivary secretions until day 15 at 20 °C. Low rates of MAYV in salivary secretions collected from infected mosquitoes provided evidence supporting the notion that a substantial salivary gland barrier(s) in Florida Ae. aegypti can limit the risk of MAYV transmission. Our results provide insights into the effects of temperature and time on the progression of infection and replication of MAYV in Ae. aegypti vectors. 相似文献
32.
Maen Abdelrahim Hadeel Al-Rawi Abdullah Esmail Jiaqiong Xu Godsfavour Umoru Fahad Ibnshamsah Ala Abudayyeh David Victor Ashish Saharia Robert McMillan Ebtesam Al Najjar Doaa Bugazia Maryam Al-Rawi Rafik M. Ghobrial 《Current oncology (Toronto, Ont.)》2022,29(5):3585
Background: The management of cholangiocarcinoma is continually reviewed on a current evidence basis to develop practice guidelines and consensus statements. However, the standardized treatment guidelines are still unclear for cholangiocarcinoma patients who are listed for liver transplantation. We aimed to validate and evaluate the potential efficacy of chemotherapy combination of Gemcitabine and Cisplatin as a neo-adjuvant treatment for cholangiocarcinoma patients before liver transplantation. Methods: In this prospective case series, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with a combination of neoadjuvant gemcitabine and cisplatin with no radiation. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center according to an open-labeled, and center-approved clinical management protocol. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. Results: Between 1 March 2016, and 15 March 2022, 10 patients (8 males and 2 females) with a median age of 62.71(interquartile range: 60.02–71.87) had a confirmed diagnosis of intrahepatic or hilar cholangiocarcinoma and underwent liver transplantation. Median days of neoadjuvant therapy for a given combination of gemcitabine and cisplatin were 181 (IRQ: 120–250). Nine patients (90%) were reported with no recurrence or metastasis, and only 1 patient had confirmed metastasis (10%); days for metastasis after transplantation were 612 for this patient. All patients received a combination of gemcitabine and cisplatin as neo-adjuvant while awaiting liver transplantation. The median days of follow-up were 851 (813–967). Overall survival was 100% (95% CI 100–100%) at both years one and two; 75% (95% CI 13–96%) at years three to five. One patient died at eight hundred and eighty-five days. No adverse events were reported after liver transplantation including the patient who was confirmed with recurrence. Conclusions: Our finding demonstrated that neo-adjuvant gemcitabine and cisplatin with no radiation prior to liver transplantation resulted in excellent outcomes for patients with cholangiocarcinoma. 相似文献
33.
Augmentation pharyngoplasty, in which tissue filler or grafts are used to augment the posterior nasopharynx, is an accepted option to treat velopharyngeal insufficiency. It is generally well tolerated and safe with limited side effects. In this study, we describe a case of a retropharyngeal abscess and Grisel syndrome following hyaluronic acid augmentation pharyngoplasty. Grisel syndrome is a serious condition that requires early diagnosis and prompt intervention to prevent further complications. 相似文献
34.
Mohammed S. Alqahtani Mohamed Abbas Mohammed Abdulmuqeet Abdullah S. Alqahtani Mohammad Y. Alshahrani Abdullah Alsabaani Murugan Ramalingam 《Materials》2022,15(14)
The COVID-19 pandemic has the tendency to affect various organizational paradigm alterations, which civilization hasyet to fully comprehend. Personal to professional, individual to corporate, and across most industries, the spectrum of transformations is vast. Economically, the globe has never been more intertwined, and it has never been subjected to such widespread disruption. While many people have felt and acknowledged the pandemic’s short-term repercussions, the resultant paradigm alterations will certainly have long-term consequences with an unknown range and severity. This review paper aims at acknowledging various approaches for the prevention, detection, and diagnosis of the SARS-CoV-2 virus using nanomaterials as a base material. A nanostructure is a material classification based on dimensionality, in proportion to the characteristic diameter and surface area. Nanoparticles, quantum dots, nanowires (NW), carbon nanotubes (CNT), thin films, and nanocomposites are some examples of various dimensions, each acting as a single unit, in terms of transport capacities. Top-down and bottom-up techniques are used to fabricate nanomaterials. The large surface-to-volume ratio of nanomaterials allows one to create extremely sensitive charge or field sensors (electrical sensors, chemical sensors, explosives detection, optical sensors, and gas sensing applications). Nanowires have potential applications in information and communication technologies, low-energy lightning, and medical sensors. Carbon nanotubes have the best environmental stability, electrical characteristics, and surface-to-volume ratio of any nanomaterial, making them ideal for bio-sensing applications. Traditional commercially available techniques have focused on clinical manifestations, as well as molecular and serological detection equipment that can identify the SARS-CoV-2 virus. Scientists are expressing a lot of interest in developing a portable and easy-to-use COVID-19 detection tool. Several unique methodologies and approaches are being investigated as feasible advanced systems capable of meeting the demands. This review article attempts to emphasize the pandemic’s aftereffects, utilising the notion of the bullwhip phenomenon’s short-term and long-term effects, and it specifies the use of nanomaterials and nanosensors for detection, prevention, diagnosis, and therapy in connection to the SARS-CoV-2. 相似文献
35.
Hammad Ahmed Shah Moncef L. Nehdi Muhammad Imtiaz Khan Usman Akmal Hisham Alabduljabbar Abdullah Mohamed Muhammad Sheraz 《Materials》2022,15(15)
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete. 相似文献
36.
37.
Al-Johar D Shinwari N Arif J Al-Sanea N Jabbar AA El-Sayed R Mashhour A Billedo G El-Doush I Al-Saleh I 《Phytotherapy research : PTR》2008,22(10):1311-1323
This study examined the chemopreventive effect of Nigella sativa and some of its antioxidant constituents on a number of colon cancer biomarkers in rats induced with azoxymethane (AOM). Sixty male Sprague-Dawley rats were randomly assigned into ten subgroups: vehicle (1-5) and experimental (6-10). The rats in each group were fed one of the following diets: basal diet, (200 mg/kg) Nigella sativa, (0.2 mg/kg) selenium, (1.2 mg/kg) all-trans-retinol plus (100 mg/kg) DL-alpha-tocopherol and (10 mg/kg) thymoquinone, respectively. Only rats in subgroups 6-10 were injected with AOM (15 mg/kg) once per week for 2 weeks. Both groups were fed their respective diets for 5 weeks. Then they were killed and examined for colonic aberrant crypt foci (ACF). Our result showed that only vitamin supplementation was effective on ACF. Nigella sativa revealed inhibitory effects only on DNA damage (day 34) in the AOM-treated rat group. Alternatively, selenium, thymoquinone and vitamins inhibited the MDA content in the liver. Although the exact mechanisms involved in the protective role of Nigella sativa against the initiation of colon carcinogenesis are not clearly understood, the results suggest that its inhibitory effects might depend on the combined competitive inhibition of various antioxidant constituents of this plant. 相似文献
38.
39.
Abdallah MA Abdullah HI Kang S Taylor DD Nakajima ST Gercel-Taylor C 《Fertility and sterility》2007,87(4):978-981
We describe our experience of over 300 cycles of preimplantation genetic diagnosis (PGD) and report clinical pregnancy rates (35%-67%) that support using this technology to screen for genetic disorders and chromosomal abnormalities. In clinical practice for over ten years, PGD offers couples the earliest form of genetic screening and may help improve ongoing pregnancy rates in poor-prognosis patients. 相似文献
40.
Doğanc T Yüksel Konuk BE Alpan N Konuk O Hämäläinen RH Lehesjoki AE Tekin M 《Clinical dysmorphology》2007,16(3):173-176
Mulibrey nanism is a rare autosomal-recessive disorder characterized by prenatal onset severe growth retardation and pericardial constriction associated with abnormalities of muscle, liver, brain and eye. More than 80% of previously reported patients are of Finnish origin in whom a founder mutation in the TRIM37 gene have been described. We report on a 7-year-old Turkish boy who presented with classical phenotypic features of mulibrey nanism. Mutation screening of the TRIM37 gene revealed that the proband had a homozygous two base pair deletion, c.1894_1895delGA, resulting in a frame-shift and a premature termination codon. Our proband is one of the rare examples of mulibrey nanism outside Finland and extends the mutation spectrum in this disorder. 相似文献