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BACKGROUND: Spina bifida is a type of neural tube defect (NTD); NTDs are developmental malformations of the spinal cord that result from failure of neural tube closure during embryogenesis and are likely caused by interactions between genetic and environmental factors. Arsenic induces NTDs in animal models, and studies demonstrate that mice with genetic defects related to folate metabolism are more susceptible to arsenic's effects. We sought to determine whether 25 single-nucleotide polymorphisms (SNPs) in genes involved in folate and arsenic metabolism modified the associations between maternal arsenic exposure and risk of spina bifida (a common NTD) among a hospital-based case-control study population in Bangladesh. METHODS: We used data from 262 mothers and 220 infants who participated in a caseâcontrol study at the National Institutes of Neurosciences & Hospital and Dhaka Shishu Hospital in Dhaka, Bangladesh. Neurosurgeons assessed infants using physical examinations, review of imaging, and we collected histories using questionnaires. We assessed arsenic from mothers' toenails using inductively coupled plasma mass spectrometry (ICP-MS), and we genotyped participants using the Illumina Global Screening Array v1.0. We chose candidate genes and SNPs through a review of the literature. We assessed SNP-environment interactions using interaction terms and stratified models, and we assessed gene-environment interactions using interaction sequence/SNP-set kernel association tests (iSKAT). RESULTS: The median toenail arsenic concentration was 0.42 µg/g (interquartile range [IQR]: 0.27-0.86) among mothers of cases and 0.47 µg/g (IQR: 0.30-0.97) among mothers of controls. We found an two SNPs in the infants' AS3MT gene (rs11191454 and rs7085104) and one SNP in mothers' DNMT1 gene (rs2228611) were associated with increased odds of spina bifida in the setting of high arsenic exposure (rs11191454, OR 3.01, 95% CI: 1.28-7.09; rs7085104, OR 2.33, 95% CI: 1.20-4.and rs2228611, OR 2.11, 95% CI: 1.11-4.01), along with significant SNP-arsenic interactions. iSKAT analyses revealed significant interactions between mothers' toenail concentrations and infants' AS3MT and MTR genes (p = 0.02), and mothers' CBS gene (p = 0.05). CONCLUSIONS: Our results support the hypothesis that arsenic increases spina bifida risk via interactions with folate and arsenic metabolic pathways and suggests that individuals in the population who have certain genetic polymorphisms in genes involved with arsenic and folate metabolism may be more susceptible than others to the arsenic teratogenicity.
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Background: Frontonasal dysplasia type-2(FND2), a rare phenotypically variable and heterogeneous developmental anomaly resulting from mutation of the ALX4 gene, is primarily characterized by malformation of the skull and facial skeleton. This study was designed to showcase a clinical, imaging, and genetic analysis of FND2 in a consanguineous family of Bangladeshi origin. Methodology: Clinical imaging and whole genome sequencing of mother, father and patient was done by using Nextera DNA flex library preparation kit (Illumina, USA) using Novaseq 6000 next generation sequencer to find out ALX4 mutation which causes FND2 in patient. Result: We report the clinical as well as molecular findings in an 8-year-old girl with FND2. The child presented with various characteristic features of skull and facial anomalies associated with FND 2 along with numerous other features many of which have not been described in previous literature. The parents also showed some key clinical, radiological, and genetic features of FND 2. The whole genome sequencing (WGS) revealed homozygosity for a 793C-T transition in the ALX4 gene, which resulted in premature termination at codon 265 (p.Arg265Ter). Both of her parents were heterozygous carriers of ALX4 mutation. Conclusions: This is the first report that associates clinical, imaging, and genomics analyses in a Bangladeshi patient for better understanding the disease FND2. These results will facilitate diagnosis and genetic counseling of the future FND2 patients.
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South Asia, consisting of Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka, spreads between the Himalayan base and the Indian Ocean and shares identical geophysical characteristics. With the inclusion of its newest member Afghanistan, these 8 member nations of the South Asian Association for Regional Cooperation (SAARC) share more or less a homogenous geographical, political, and historical background and cultural heritage, with a significant role in shaping the world. This densely populated area is home to around a quarter of the world's total population. From the ancient ages, the neurosurgical practice has paced relentlessly and in the last 100 years, it has reached its zenith. With modern advancements, neurosurgery has developed in its diagnostic and treatment modalities along with facilities for training and education. Despite falling behind owing to economic, educational, and geopolitical constraints, the pioneers of the SAARC region have established the fields of neurosurgery in their respective countries with command. No constraint could stop them from educating and training young physicians to make competent neurosurgeons to evolve the field of neurosurgery in their countries. Their firm determination and hard work paved the way to keep this field striving and thriving, to serve a substantial volume of the world population with their neurosurgical insight and skill. However, this region needs to go a long way as the number of neurosurgeons and facilities is still insufficient. This can be achieved with the guidance and collaboration among the neurosurgeons of the SAARC region as the youth here are talented and hardworking.
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BACKGROUND: Spina bifida, a developmental malformation of the spinal cord, is associated with high rates of mortality and disability. Although folic acid-based preventive strategies have been successful in reducing rates of spina bifida, some areas continue to be at higher risk because of chemical exposures. Bangladesh has high arsenic exposures through contaminated drinking water and high rates of spina bifida. This study examines the relationships between mother's arsenic exposure, folic acid, and spina bifida risk in Bangladesh. METHODS: We conducted a hospital-based case-control study at the National Institute of Neurosciences & Hospital (NINS&H) in Dhaka, Bangladesh, between December 2016 and December 2022. Cases were infants under age one year with spina bifida and further classified by a neurosurgeon and imaging. Controls were drawn from children seen at NINS&H and nearby Dhaka Shishu Hospital. Mothers reported folic acid use during pregnancy, and we assessed folate status with serum assays. Arsenic exposure was estimated in drinking water using graphite furnace atomic absorption spectrophotometry (GF-AAS) and in toenails using inductively coupled plasma mass spectrometry (ICP-MS). We used logistic regression to examine the associations between arsenic and spina bifida. We used stratified models to examine the associations between folic acid and spina bifida at different levels of arsenic exposure. RESULTS: We evaluated data from 294 cases of spina bifida and 163 controls. We did not find a main effect of mother's arsenic exposure on spina bifida risk. However, in stratified analyses, folic acid use was associated with lower odds of spina bifida (adjusted odds ratio [OR]: 0.50, 95% confidence interval [CI]: 0.25-1.00, p = 0.05) among women with toenail arsenic concentrations below the median value of 0.46 µg/g, and no association was seen among mothers with toenail arsenic concentrations higher than 0.46 µg/g (adjusted OR: 1.09, 95% CI: 0.52-2.29, p = 0.82). CONCLUSIONS: Mother's arsenic exposure modified the protective association of folic acid with spina bifida. Increased surveillance and additional preventive strategies, such as folic acid fortification and reduction of arsenic, are needed in areas of high arsenic exposure.
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Arsenic , Acide folique , Dysraphie spinale , Humains , Acide folique/usage thérapeutique , Bangladesh/épidémiologie , Dysraphie spinale/prévention et contrôle , Dysraphie spinale/épidémiologie , Dysraphie spinale/induit chimiquement , Études cas-témoins , Femelle , Arsenic/analyse , Nourrisson , Mâle , Adulte , Nouveau-né , Grossesse , Polluants chimiques de l'eau/analyse , Exposition maternelle , Jeune adulte , Eau de boisson/composition chimique , Eau de boisson/analyseRÉSUMÉ
OBJECTIVE: Reports on the management and survival of children with myelomeningocele defects in Bangladesh are limited. This study describes the characteristics and outcomes of these children, focusing on the timing of surgical repair and factors affecting survival. METHODS: We enrolled patients with myelomeningoceles in a case-control study on arsenic exposure and spina bifida in Bangladesh. Cases were subsequently followed at regular intervals to assess survival. Demographic, clinical, and surgical characteristics were reviewed. Univariate tests identified factors affecting survival. RESULTS: Between 2016 and 2022, we enrolled 272 patients with myelomeningocele. Postnatal surgical repair was performed in 63% of cases. However, surgery within 5 days after birth was infrequent (<10%) due to delayed presentation, and there was a high rate (29%) of preoperative deaths. Surgical repair significantly improved patient survival (P < 0.0001). Older age at time of surgery was also associated with improved survival rates, which most likely represents that those who survived to older ages prior to surgery accommodated better with their lesions. Patients who presented with ruptured lesions had lower survival rates. CONCLUSIONS: Timely neurosurgical repair of myelomeningoceles in Bangladesh is hindered by late patient presentation, resulting in a high preoperative patient death rate. Neurosurgical intervention remains a significant predictor of survival. Increased access to neurosurgical care and education of families and non-neurosurgical providers on the need for timely surgical intervention are important for improving the survival of infants with myelomeningoceles.
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Myéloméningocèle , Procédures de neurochirurgie , Humains , Bangladesh/épidémiologie , Myéloméningocèle/chirurgie , Mâle , Femelle , Procédures de neurochirurgie/méthodes , Nourrisson , Études cas-témoins , Nouveau-né , Enfant d'âge préscolaire , Délai jusqu'au traitement , Enfant , Résultat thérapeutique , Taux de survieRÉSUMÉ
Background: Spina bifida, a developmental malformation of the spinal cord, is associated with high rates of mortality and disability. Although folic acid-based preventive strategies have been successful in reducing rates of spina bifida, some areas continue to be at higher risk because of chemical exposures. Bangladesh has high arsenic exposures through contaminated drinking water and high rates of spina bifida. Methods: We conducted a hospital-based case-control study at the National Institute of Neurosciences & Hospital (NINS&H) in Dhaka, Bangladesh, between December 2016 and December 2022. Cases were infants under age one year with spina bifida and further classified using data from observations by neurosurgeons and available imaging. Controls were drawn from children who presented to NINS&H or Dhaka Shishu Hospital (DSH) during the same study period. Mothers reported folic acid use during pregnancy, and we assessed folate status with serum assays. Arsenic exposure was estimated in drinking water using graphite furnace atomic absorption spectrophotometry (GF-AAS) and in toenails using inductively coupled plasma mass spectrometry (ICP-MS). Results: We evaluated data from 294 cases of spina bifida and 163 controls. We did not find a main effect of mother's arsenic exposure on spina bifida risk. However, in stratified analyses, folic acid use was associated with lower odds of spina bifida (adjusted odds ratio [OR]: 0.50, 95% confidence interval [CI]: 0.25-1.00, p = 0.05) among women with toenail arsenic concentrations below the median, and no association was seen among mothers with toenail arsenic concentrations higher than median (adjusted OR: 1.09, 95% CI: 0.52-2.29, p = 0.82). Conclusions: Mother's arsenic exposure modified the protective association of folic acid with spina bifida. Increased surveillance and additional preventive strategies, such as folic acid fortification and reduction of arsenic, are needed in areas of high arsenic exposure.
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Background and Objectives: Juvenile nasopharyngeal angiofibroma (JNA) is an angiomatous hamartoma of the nasal cavity. It is a benign but locally aggressive vascular tumor of the nasopharynx affecting adolescent males. Many surgical procedures are in practice, but the extended endonasal endoscopic (EEE) approach for JNAs is a suitable and effective technique. Materials and Methods: Fifteen adolescent patients having JNA who underwent extended endonasal endoscopic (EEE) surgery from January 2010 to January 2022 were studied retrospectively. Patients having residual and recurrent JNAs and those who underwent surgery other than EEE were excluded. Results: The average age of the patients was 18.3 years of age. A total of six patients (40%) each had stage V and IV while three patients (20%) had stage III JNAs. Gross total removal was achieved in eight (53.3%) patients and seven (43.7%) had partial removal. There was no per or postoperative mortality. All the patients had at least 3 years of postoperative follow-up and during follow-ups, seven patients were found to have residual tumors, and two had recurrences. Discussion: During the last decades, the endoscopic approach for the resection of JNAs has gained increasing popularity due to its obvious advantages over transfacial approaches. The magnified and angled field of view "behind the corner" helping in a more complete inspection for the resection and shorter hospitalization time makes it a better choice than the other approaches. Conclusions: Endoscopy is an excellent approach for primary JNA. It allows well visualization and precise removal of the angiofibroma. An endoscopic multiangle, multicorridor skull base approach including Denker's anteromedial maxillotomy is suitable and preferable for the resection of extensive JNAs.
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Angiofibrome , Tumeurs du rhinopharynx , Adolescent , Mâle , Humains , Angiofibrome/chirurgie , Radiothérapie adjuvante , Études rétrospectives , Endoscopie , Tumeurs du rhinopharynx/radiothérapie , Tumeurs du rhinopharynx/chirurgieRÉSUMÉ
Label-free surface-enhanced Raman spectroscopy (SERS) has been proposed as a promising bacterial detection technique. However, the quality of the collected bacterial spectra can be affected by the time between sample acquisition and the SERS measurement. This study evaluated how storage stress stimuli influence the label-free SERS spectra of Pseudomonas syringae samples stored in phosphate buffered saline. The results indicate that when faced with nutrient limitations and changes in osmatic pressure, samples at room temperature (25 °C) exhibit more significant spectral changes than those stored at cold temperature (4 °C). At higher temperatures, bacterial communities secrete extracellular biomolecules that induce programmed cell death and result in increases in the supernatant SERS signals. Surviving cells consume cellular components to support their metabolism, thus leading to measurable declines in cell SERS intensity. Two-dimensional correlation spectroscopy analysis suggests that cellular component signatures decline sequentially in the following order: proteins, nucleic acids, and lipids. Extracellular nucleic acids, proteins, and carbohydrates are secreted in turn. After subtracting the SERS changes resulting from storage, we evaluated bacterial response to viral infection. P. syringae SERS profile changes enable accurate bacteriophage Phi6 quantification over the range of 104-1010 PFU/mL. The results indicate that storage conditions impact bacterial label-free SERS signals and that such influences need to be accounted for and if possible avoided when detecting bacteria or evaluating bacterial response to stress stimuli.
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Bactéries , Acides nucléiques , Bactéries/métabolisme , Analyse spectrale Raman/méthodes , Protéines/métabolisme , Acides nucléiques/métabolismeRÉSUMÉ
In this study, the concentrations of iodine in household salt samples (n = 690) were determined by following the iodometric titration method, and the health risks of Bangladeshi people were assessed based on the semi-probabilistic approach and the US Environmental Protection Agency (USEPA) deterministic model. After adjusting 20% of cooking losses, the iodine concentration (mean, range) in salt samples of Phultala, Dighalia, Terokhada, Rupsha, Batiaghata, Dumuria, Paikgacha, Koyra, Dacope, and KCC was (29.68 ± 8.67, 14.39-48.26), (31.05 ± 6.68, 15.24-43.18), (26.94 ± 5.57, 16.09-45.72), (24.33 ± 5.61, 12.70-37.26), (26.69 ± 6.73, 10.16-44.87), (27.20 ± 8.44, 9.31-53.34), (27.71 ± 8.09, 8.46-47.42), (28.39 ± 7.80, 11.01-46.57), (28.20 ± 7.97, 3.38-49.10), and (29.21 ± 6.62, 18.62-40.64) mg/kg, respectively. The iodine contents in 97.25% of samples were within the standard fortification level of Bangladesh (15-50 mg/kg), while 2.61% of samples were below this limit. The semi-probabilistic risk assessment studies showed that 80.14% of samples at a low ingestion rate could provide optimal nutrition (150-299 µg/day) to the whole population. Contrarily, at medium, moderate-high, and high consumption rates 34.93%, 65.22%, and 85.94% of samples, respectively, belonged to above the requirements to excessive exposure categories (300-1100 µg/day), which might cause iodine-induced diseases. The target hazard quotient (THQ) values for the adults in most of the samples were within the threshold risk limit (THQ < 1.0), whereas THQ values in 6.82% to 85.97% of samples for the children at low to high ingestion rates, respectively exceeded this limit, which revealed that the adults were almost safe, but the children might face non-carcinogenic health effects. Therefore, regular monitoring of iodine concentration in iodized salts should be done to prevent iodine deficiency or iodine-induced disorders.
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Iode , Chlorure de sodium alimentaire , Adulte , Enfant , Humains , Bangladesh/épidémiologie , Études transversales , Chlorure de sodium alimentaire/analyse , Chlorure de sodium , Appréciation des risquesRÉSUMÉ
Surface-enhanced Raman spectroscopy (SERS) has great potential as an analytical technique for environmental analyses. In this study, we fabricated highly porous gold (Au) supraparticles (i.e., â¼100 µm diameter agglomerates of primary nano-sized particles) and evaluated their applicability as SERS substrates for the sensitive detection of environmental contaminants. Facile supraparticle fabrication was achieved by evaporating a droplet containing an Au and polystyrene (PS) nanoparticle mixture on a superamphiphobic nanofilament substrate. Porous Au supraparticles were obtained through the removal of the PS phase by calcination at 500 °C. The porosity of the Au supraparticles was readily adjusted by varying the volumetric ratios of Au and PS nanoparticles. Six environmental contaminants (malachite green isothiocyanate, rhodamine B, benzenethiol, atrazine, adenine, and gene segment) were successfully adsorbed to the porous Au supraparticles, and their distinct SERS spectra were obtained. The observed linear dependence of the characteristic Raman peak intensity for each environmental contaminant on its aqueous concentration reveals the quantitative SERS detection capability by porous Au supraparticles. The limit of detection (LOD) for the six environmental contaminants ranged from â¼10 nM to â¼10 µM, which depends on analyte affinity to the porous Au supraparticles and analyte intrinsic Raman cross-sections. The porous Au supraparticles enabled multiplex SERS detection and maintained comparable SERS detection sensitivity in wastewater influent. Overall, we envision that the Au supraparticles can potentially serve as practical and sensitive SERS devices for environmental analysis applications.
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An improved understanding of bacterial inactivation mechanisms will provide useful insights for infectious disease control and prevention. We evaluated bacterial response to several inactivation methods using surface-enhanced Raman spectroscopy (SERS). The results indicate that changes in the SERS signal are highly related to cellular disruption and that cellular changes arising after cell inactivation cannot be ignored. The membrane integrity of heat and the combination of UV254 and free chlorine (UV254/chlorine) treated Pseudomonas syringae (P. syringae) cells were severely disrupted, leading to significantly increased peak intensities. Conversely, ethanol treated bacteria exhibited intact cell morphologies and the SERS spectra remained virtually unchanged. On the basis of time dependent SERS signals, we extracted dominant SERS patterns. Peaks related to nucleic acids accounted for the main changes observed during heat, UV254, and UV254/chlorine treatment, likely due to their outward diffusion from the cell cytoplasm. For free chlorine treated P. syringae, carbohydrates and proteins on the cell membrane were denatured or lost, resulting in a decrease in related peak intensities. The nucleobases were likely oxidized when treated with UV254 and chlorine, thus leading to shifts in the related peaks. The generality of the method was verified using two additional bacterial strains: Escherichia coli and Bacillus subtilis as well as in different water matrices. The results suggest that SERS spectral analysis is a promising means to examine bacterial stress response at the molecular level and has applicability in diverse environmental implementations.
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Infections à Escherichia coli , Analyse spectrale Raman , Bacillus subtilis , Chlore/pharmacologie , Escherichia coli , Humains , Analyse spectrale Raman/méthodesRÉSUMÉ
(1) Introduction: Primary intraosseous osteolytic meningiomas (PIOM) are non-dural-based tumors predominantly presenting an osteolytic component with or without hyperostotic reactions. They are a subset of primary extradural meningiomas (PEM). In this study, we present a peculiar case with a systematic literature review and propose a new classification considering the limitations of previous classification systems. (2) Materials and Methods: Using a systematic search protocol in Google Scholar, PubMed, and Scopus databases, we extracted all case studies on PIOM published from inception to December 2020. A 46-year-old female patient form Dhaka, Bangladesh, was also described. The search protocol was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. (3) Results: Here, we present a 46-year-old female patient with PIOM who successfully underwent bifrontal craniotomy and gross total removal (GTR) of the tumor. At 6-month follow-up, no tumor recurrence was shown. Including our new case, 55 total cases from 47 articles were included in the analysis. PIOMs were in closer frequency among males (56.4%) and females (43.6%). The most common tumor location was the frontal and parietal calvarium, most commonly in the frontal bone (29.1%). Surgical resection was the predominant modality of treatment (87.3%); only 1.8% of patients were treated with radiotherapy, and 5.4% received a combination of surgery and radiotherapy. Gross total resection (GTR) was achieved in 80% of cases. Extracranial extension was reported in 41.8% of cases, dural invasion in 47.3%, and recurrence in 7.3%. Whole-body 68 Ga-DOTATOC PET/CT has also been reported as a useful tool both for differential diagnosis, radiotherapy contouring, and follow-up. Current treatments such as hydroxyurea and bevacizumab have variable success rates. We have also suggested a new classification which would provide a simple common ground for further research in this field. (4) Conclusions: Surgical resection, especially GTR, is the treatment of choice for PIOM, with a high GTR rate and low risk of complications and mortality. More research is needed on the differential diagnosis and specific treatment of PIOM.
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BACKGROUND: Vascular injuries occur in approximately 25% of all penetrating neck traumas, with carotid artery injuries being particularly lethal. Penetrating neck injuries are potentially fatal. Vascular injuries occur in approximately 25% of cases, which can lead to the formation of arteriovenous fistulas. CASE DESCRIPTION: The authors present a case of delayed open surgery to repair a carotid-jugular fistula that resulted in an unprecedented complication, as well as a brief review of the condition's diagnosis and treatment options. CONCLUSION: This case report suggests us that, penetrating neck injuries should be thoroughly evaluated for arteriovenous fistulae. To avoid complications, common carotid-jugular fistulas must be treated as soon as possible. Postoperative complications can be effectively managed with prompt action.
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The impacts of the ongoing coronavirus pandemic highlight the importance of environmental monitoring to inform public health safety. Wastewater based epidemiology (WBE) has drawn interest as a tool for analysis of biomarkers in wastewater networks. Wide scale implementation of WBE requires a variety of field deployable analytical tools for real-time monitoring. Nanobiotechnology enabled sensing platforms offer potential as biosensors capable of highly efficient and sensitive detection of target analytes. This review provides an overview of the design and working principles of nanobiotechnology enabled biosensors and recent progress on the use of biosensors in detection of biomarkers. In addition, applications of biosensors for analysis of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus are highlighted as they relate to the potential expanded use of biosensors for WBE-based monitoring. Finally, we discuss the opportunities and challenges in future applications of biosensors in WBE for effective monitoring and investigation of public health threats.
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Objective Gliomas, the most frequent primary brain tumors, have various grades, among which grade II, III, and IV are diffusely infiltrating astrocytomas. As therapeutic approaches and outcome differ considerably, depending on the grade of these tumors, prediction is important regarding outcome. Magnetic resonance spectroscopy (MRS) can be of help in understanding of the biochemical changes of pathological state to study, monitor, predict grading and outcome of gliomas. Materials and Methods All the 30 patients in the study with intracranial diffusely infiltrating astrocytoma had MRS study using 1.5 Tesla MR scanner. The study population was divided into three groups on the basis of the grades of the tumor according to histopathology. Mean height of choline (Ch), N-acetyl aspartate (NAA), creatine (Cr) peak, and choline/creatine (Ch/Cr) ratio was documented. Mean value of each variable among three grades was analyzed and compared with analysis of variance (ANOVA) test (F-test). Results There was positive relationship regarding Ch/Cr ratio among astrocytomas grade II to IV and the result was significant ( p = 0.047). A positive relationship of Ch peak was also observed for grade II to IV astrocytoma, though the result was not significant ( p = 0.578). The result was nonsignificant for NAA ( p = 0.696) and Cr ( p = 0.740) peak also. Conclusion We recommend Ch/Cr ratio to be considered as a dependable MRS data to comment on low- or high-grade astrocytomas. MRS can be done as a routine investigation in the developing countries for astrocytomas where other facilities are less accessible for reliable prediction and counseling.
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Bacterial cellulose nanocrystals (BCNCs) are biocompatible cellulose nanomaterials that can host guest nanoparticles to form hybrid nanocomposites with a wide range of applications. Herein, we report the synthesis of a hybrid nanocomposite that consists of plasmonic gold nanoparticles (AuNPs) and superparamagnetic iron oxide (Fe3O4) nanoparticles supported on BCNCs. As a proof of concept, the hybrid nanocomposites were employed to isolate and detect malachite green isothiocyanate (MGITC) via magnetic separation and surface-enhanced Raman scattering (SERS). Different initial gold precursor (Au3+) concentrations altered the size and morphology of the AuNPs formed on the nanocomposites. The use of 5 and 10 mM Au3+ led to a heterogenous mix of spherical and nanoplate AuNPs with increased SERS enhancements, as compared to the more uniform AuNPs formed using 1 mM Au3+. Rapid and sensitive detection of MGITC at concentrations as low as 10-10 M was achieved. The SERS intensity of the normalized Raman peak at 1175 cm-1 exhibited a log-linear relationship for MGITC concentrations between 2 × 10-10 and 2 × 10-5 M for Au@Fe3O4@BCNCs. These results suggest the potential of these hybrid nanocomposites for application in a broad range of analyte detection strategies.
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Cellulose/composition chimique , Or/composition chimique , Nanoparticules de magnétite/composition chimique , Nanoparticules métalliques/composition chimique , Nanocomposites/composition chimique , Magenta I/analyse , Gluconacetobacter xylinus/composition chimique , Limite de détection , Étude de validation de principe , Analyse spectrale RamanRÉSUMÉ
Neurenteric cysts are rare congenital lesions of benign nature that can be encountered at any level of the neuraxis, starting from the cranium down to coccyx. Rewarding outcome can be achieved with early diagnosis and complete removal of these benign lesions. Here, we report a case of a huge neurenteric cyst in an 11-year-old boy at the ventral craniocervical junction, a rarely reported entity with literature review. In this article, we focus on the clinical presentation, pathogenesis, radiological findings, surgery, and surgical outcome of this benign lesion, as we succeeded to have gratifying result following surgery in our instance.
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Chronic periapical abscess drains through a sinus tract either intraorally or extraorally. However, intraoral drainage is more common than extraoral in both dentitions. Nevertheless, the simultaneous presentation of extraoral and intraoral sinus tract is very rarely reported in primary dentition. This case report discussed the management of a girl aged 7 years with a chronic periapical abscess of tooth no. 85 with both non-healing extraoral and intraoral sinus tract having multiple stomata. Non-vital pulpectomy using calcium hydroxide paste intracanal dressing was performed initially until 2 weeks without remarkable healing; then antibiotic dressing consisting of a mixture of ciprofloxacin, metronidazole and clindamycin was placed as an intracanal medicament for 1 week, which shows uneventful healing of both intraoral and extraoral sinus tract. This case report clearly indicates about how history, correct diagnosis and appropriate treatment of endodontic infection associated with sinus tract can be conservatively healed with endodontic treatment alone.