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A central and critical step in the molecular detection of soil-transmitted helminths from environmental sources is the extraction of DNA from the eggs. In this study, we investigated the yield of DNA extracted from known quantities (500, 100, 50, 20, 10 and 5) of Ascaris suum eggs, as well as directly from wastewater and sludge samples containing Ascaris spp. eggs, using six commercial DNA extraction kits. The amount of DNA extracted was quantified with NanoDrop, Qubit and Ct values from quantitative polymerase chain reaction (qPCR) assay using CFX96 Touch™ real-time PCR equipment. The PowerLyzer Ultraclean Microbial DNA isolation kit and PowerSoil DNA isolation kit gave the highest yield of DNA based on the NanoDrop, Qubit and Ct values. However, the qPCR results indicate that in some of the kits, PCR inhibitors may have been carried over to the PCR reaction. DNA extraction kits that incorporate a bead-beating step as well as other mechanical eggshell disruption steps were superior in extracting DNA from Ascaris spp. eggs. Additionally, for the accurate quantification of extracted DNA, the use of Ct values from qPCR and Qubit readings gives better results compared to the NanoDrop readings. For efficient downstream applications, the use of DNA extraction kits with superior inhibitor removal technology is essential, in addition to a high yield of DNA.
Background: The Endoscopic endonasal approach (EEA) has been gaining popularity in the past decade as an alternative to traditional transcranial and transorbital approaches. We have performed orbital apex decompression for a variety of pathological entities. Methods: We performed a retrospective chart review on patients who underwent EEA orbital apex decompression between January 1st 2010 and December 1st 2018 at McMaster University. Results: Eight patients underwent endoscopic endonasal orbital decompression at our center, including five male patients and three female patients. The mean age of our patients was 50.1 years. The different pathologies we treated included nasopharyngeal carcinoma, hemangioma, fibrous dysplasia, IgG4 disease, inverted papilloma, angioleiomyoma, and neuroendocrine paraganglioma. Five patients presented with visual symptoms. Postoperatively, one of these five patients improved to baseline, three had stable vision, another one had progressive visual decline despite surgical intervention. Conclusions: Endoscopic endonasal approach can be used as an alternative to decompress orbital apex pathologies in selected patients.
Background: The Endoscopic endonasal approach (EEA) has become increasingly popular in the treatment of suprasellar meningiomas, which often cause visual symptoms due to compression of the anterior optic apparatus. Methods: We performed a retrospective chart review on patients who underwent EEA optic nerve decompression and resection of suprasellar meningiomas between January 1st 2005 and December 1st 2018 at McMaster University. Results: The mean age of our patients was 59.8 years. We treated 9 male and 23 female patients, with a mean follow up of 6.29 years. 23 patients (71.9%) presented with visual symptoms, with a mean duration of 8.65 months. In our patient cohort, 95.5% had stable or improved visual acuity postoperatively. Less than six months of visual decline was more likely to be associated with postoperative improvement of visual acuity, with an odds ratio (OR) of 0.0222 (95% CI: 0.0017–0.289, p<0.05); as well as visual field (OR:0.0625; 95% CI, 0.0042–0.915, p<0.05). Additionally, the absence of RAPD was associated with improved postoperative visual acuity (OR: 0.0675; 95% CI, 0.0354–0.706, p<0.05). Conclusions: Endoscopic endonasal approach can achieve good visual outcome in patients harboring suprasellar meningiomas. Symptom duration of less than six months and absence of RAPD were positive predictor of postoperative visual outcome.
Background: Central neurocytoma’s are typically located in the lateral ventricles and are optimally treated with surgical resection. Surgical entry into the ventricles are associated with a number of complications, including subdural hygroma and shunt-dependent hydrocephalus. Methods: We report a patient who developed acute bilateral uncal herniation from progessively enlarging subdural hygromas following intraventricular tumour resection. Results: A 60-year-old female underwent minimally invasive transcortical transventricular resection of an intraventricular CN. The patient’s postoperative course was complicated by repeated presentations to the emergency department due to persistent and intractable nausea and headaches, without focal neurological deficits. Imaging demonstrated small bilateral subdural hygromas. The patient eventually presented with acute deterioration in her level of consciousness with clinical and radiologic evidence of bilateral uncal herniation, requiring urgent insertion of a subdural drain to treat elevated intracranial pressure (ICP). After insertion of a ventriculoperitoneal shunt, the patient was discharged in stable condition and is currently followed by the multi-disciplinary neuro-oncology team. Conclusions: Bilateral subdural hygroma could mask underlying external hydrocephalus post transventricular surgeries. Patients who are symptomatic from bilateral subdural hygromas after transventricular resection of tumors should be carefully monitored for radiographic or clinical progression, in order to avoid acute deterioration caused by elevated ICP.
We assessed the impact of personal protective equipment (PPE) doffing errors on healthcare worker (HCW) contamination with multidrug-resistant organisms (MDROs).
Prospective, observational study.
The study was conducted at 4 adult ICUs at 1 tertiary-care teaching hospital.
HCWs who cared for patients on contact precautions for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci, or multidrug-resistant gram-negative bacilli were enrolled. Samples were collected from standardized areas of patient body, garb sites, and high-touch environmental surfaces in patient rooms. HCW hands, gloves, PPE, and equipment were sampled before and after patient interaction. Research personnel observed PPE doffing and coded errors based on CDC guidelines.
We enrolled 125 HCWs; most were nurses (66.4%) or physicians (19.2%). During the study, 95 patients were on contact precautions for MRSA. Among 5,093 cultured sites (HCW, patient, environment), 652 (14.7%) yielded the target MDRO. Moreover, 45 HCWs (36%) were contaminated with the target MDRO after patient interactions, including 4 (3.2%) on hands and 38 (30.4%) on PPE. Overall, 49 HCWs (39.2%) made multiple doffing errors and were more likely to have contaminated clothes following a patient interaction (risk ratio [RR], 4.69; P = .04). All 4 HCWs with hand contamination made doffing errors. The risk of hand contamination was higher when gloves were removed before gowns during PPE doffing (RR, 11.76; P = .025).
When caring for patients on CP for MDROs, HCWs appear to have differential risk for hand contamination based on their method of doffing PPE. An intervention as simple as reinforcing the preferred order of doffing may reduce HCW contamination with MDROs.
Trait-specific characterization of rice landraces has significant potential for germplasm management, varietal identification and mining of novel gene/allele for various traits. In the current study, we have characterized 98 unique rice landraces collected from coastal regions of India, affected by submergence and salinity, based on Sub1 and Saltol quantitative trait loci (QTL) linked microsatellite markers. Among these genotypes, four genotypes (IC536558, IC536559, IC536604 and IC536604-1) collected from Kerala and two genotypes (AC34902 and IC324589) collected from West Bengal were identified with tolerance to submergence and salinity stress. A high level of genetic diversity of He = 0.349 and 0.529 at Sub1 and Saltol QTL region was detected by QTL-linked microsatellite markers, respectively. At Sub1 region one genotype, AC34902, was detected with maximum allelic similarity with FR13A, a known submergence tolerant variety. Besides, five genotypes (IC211188-1, IC536604-1, IC536604, IC536558 and IC536559) showed comparatively close genetic relationship with the salt tolerant variety FL478 for Saltol QTL and were clustered together in the neighbour joining dendrogram. Considering the haplotype structure, five genotypes (IC203801, IC203778, IC324584, IC413608 and IC413638) were identified which did not contain any common allele similar to FR13A but were still tolerant to submergence. These individuals need further characterization for identification of new alleles responsible for their tolerance.
Background: A surgical technique for foramen magnum decompression of Chiari malformation I in 11 patients is described. Methods: We used minimally invasive tubular retractors (METRx Quadrant) attached to a flexible arm to keep the retractor in a fixed position, while allowing flexible angulation under fluoroscopic guidance. Despite the small surgical opening, this approach allowed access to a wide working area, minimized soft tissue exposure, and optimized extent of decompression. For some patients, only the outer layer of dura was opened, but in cases where clinically indicated, a duraplasty was performed. Results: Postoperative CT head demonstrated satisfactory bony removal, and MRI with CSF flow study showed restoration, or significant improvement to CSF flow around the foramen magnum. There was a low incidence of post-operative complications, and the average length of hospital stay was around 1 day (1.2). For 10 out of 11 patients; their symptoms completely resolved on last follow-up, and for those who had syringomyelia, they demonstrated a radiological evidence of syrinx reduction or resolution. Conclusions: Based on our experience with this technique in foramen magnum decompression of Chiari malformation I, minimally invasive tubular retractor is a useful tool, providing the surgeon with enhanced visualization of the operative field, while reducing potential damage to tissue, and optimizing surgical outcomes.
Background: Multiple modalities have been used in the treatment of syringomyelia, including direct drainage, shunting into peritoneal, pleural and subarachnoid spaces. The authors report their experience of surgical treatment of syringomyelia in a minimally invasive fashion. Methods: We conducted a single-center retrospective chart review on our syringomyelia cases treated with minimally invasively using Metrx Quadrant retractor system since January 2011. Lateral fluoroscopy was used to guide the placement of the retractor onto the lamina of the corresponding level. This was followed by laminectomy and a small durotomy. Once the syrinx cavity was identified and the proximal end of the tubing was inserted into the syrinx cavity, the tubing was tunneled into the pleural incision subcutaneously. Insertion of the pleural end of the shunt was performed under the microscope, with removal of a small amount of the rib at its upper edge. Results: 10 procedures were performed in 7 patients by the senior author. Etiologies of syringomyelia included Chiari malformation, trauma, diastematomyelia and kyphoscoliosis. All patients improved neurologically. No patients had immediate postoperative complications. One patient underwent two revisions of syringopleural shunts due to multilobulated nature of syringomyelia. Conclusions: Our case series presents a novel, minimally invasive technique for shunting of syringomyelia with results comparable to open procedures.
Background: Microvascular decompression (MVD) is commonly used in the treatment of trigeminal neuralgia with positive clinical outcomes. Fully endoscopic microvascular decompression (E-MVD) has been proposed as a minimally invasive, effective alternative, but a comparative review of the two approaches in the literature has not been conducted. Methods: We performed a meta-analysis comparing patient outcome rates and complications for both techniques. From a pool of 1,039 studies, 22 articles were selected for review: 12 open MVD and 10 E-MVD. The total number of patients was 6,734. Results: Good pain relief was achieved in 81% of MVD and 88% of E-MVD patients, with a mean recurrence rate of 14% and 9% respectively. Average rates of complications in MVD versus E-MVD included facial paresis or weakness, 9%, 3%; -hearing loss, 4%, 1%; cerebrospinal leak, both 3%; cerebellar damage and infection, 2%, <1%; and mortality <1%, 0% respectively. Conclusions: The reviewed literature revealed similar clinical outcomes with respect to pain relief for both approaches. Recurrence rate and incidence of complications, notably facial paresis and hearing loss were higher for MVD. We concluded that E-MVD appears to offer at least as good a surgical outcome as MVD, with possibly a shorter operative time, smaller craniectomy and lower recurrence rates.
Background: The trigemino-cardiac reflex (TCR) is a sudden onset of bradycardia, hypotension, apnea or gastric hypermotility during stimulation of the trigeminal nerve. Methods: We conducted a MEDLINE search for surgical cases of TCR and herein describe a case seen recently at our institution. Results: A 60 year-old female underwent a left orbitozygomatic craniotomy for resection of a skull-base tumor. Pre-operative anesthesia evaluation was unremarkable and negative for a history of cardiovascular disease. Intra-operatively, retraction with moderate force of the temporalis muscle consistently produced asystole. Cessation of retraction resulted in immediate return of sinus rhythm. Otherwise, intra-operative heart rate was 60-90 BPM. Post-operatively, vital signs and clinical course were unremarkable. The patient experienced a similar phenomenon during an operation 6 years earlier, when manipulation of tumor near cranial nerves IX/X resulted in bradycardia. TCR is the result of a polysynaptic brainstem network involving the afferent trigeminal sensory nucleus, the reticular formation, and the efferent vagal motor nucleus. Conclusions: This is a case of exaggerated vagal response following manipulation of the temporalis muscle. Our report emphasizes the importance for neurosurgeons and anesthesiologists alike to be wary of TCR in order to avoid deleterious consequences when operating on structures associated with the trigeminal nerve.
Background: Post-craniotomy pain can be severe and undermanaged. While opioids are the mainstay treatment, they have the potential to interfere with neurological monitoring. The objectives of this review are: 1) to identify measures to provide opioid-free analgesia 2) to compare the effectiveness of non-opioid to opioid analgesia in post-craniotomy pain. Methods: A comprehensive search of EMBASE, MEDLINE, and the Cochrane Central Registry of Controlled Trials (CENTRAL) databases was conducted for RCTs evaluating the effect of opioid vs non-opioid pain control strategies in patients undergoing supratentorial craniotomy. Results: The literature search yielded 462 citations, 5 RCTs that met the inclusion criteria for a total of 250 patients. Scalp infiltration/block was found to provide equivalent analgesia to morphine1 and fentanyl.2 Morphine was associated with slightly higher postoperative nausea and vomiting. Paracetamol was less likely to induce nausea and vomiting,3,4 but provided inadequate pain relief compared to nalbuphine,3 tramadol,3 morphine4 and sufentanil.4 Dexmedetomidine5 provided similar analgesia to remifentanil but did delay the time to first dose of rescue analgesia with similar side effects. Conclusions: Based on the limited number of RCTs comparing opioid to non-opioid techniques, no definite recommendations can be made with regards to the optimal management of post-craniotomy pain. Considerations should be made for use of multimodal analgesia-including adjuvant analgesics.
The meteoroid ablation is an important source of upper atmosphere metal atoms. Many meteoroids ablate between 70 - 110 km and form an ionized plasma trail which is detected by radar technique. It is also known that the ablation heights of the meteors depend on various factors such as velocity, mass, and its composition, etc. The meteor ablation height provides new opportunities to gather information on the neutral atmosphere in the Mesosphere and Lower Thermosphere (MLT) region. In this study, we analysed the 11 years of meteor radar data (2005 - 2015), i.e., descending phase of solar cycle 23, and ascending phase of solar cycle 24, detected by all sky meteor radar at Thumba. We found that the solar activity influences the meteor ablation height, here, during the solar maxima meteor peak detection height rise to few hundred meters higher altitudes. We also examined the long term pattern of the meteor count rate which shows a decreasing trend and has good agreement with the sunspot number (SSN).
In the present paper, we analyzed the effects of magnetic field on the three dimensional flow of a nanofluid having the suspension of ferrous nano-particles within the framework of a non-uniformly thicked sheet in a slip flow regime. The sheet of variable thickness is assumed to be stretched in horizontal and transverse directions. The effects of thermophoretic forces and Brownian motion have also been incorporated into the governing equations. The RK-Fehlberg-integration scheme with shooting technique is employed to resolve the altered governing non-linear differential equations. Velocity, temperature and concentration profiles are presented and discussed for two cases namely uniform thickness stretching sheet UTSS (n = 1) and variable thickness stretching sheet VTSS (n ≠ 1), and skin friction coefficient, reduced Nusselt number and Sherwood number are computed and analyzed through tables. The results reveal that heat and mass transfer processes over slendering sheet matches with those over a flat sheet in the presence of slip flow regime.
Volumetric-modulated arc therapy (VMAT) is an advanced form of intensity-modulated radiation therapy that reduces treatment time without compromising plan quality. This study assessed acute toxicities in patients having carcinomas of oropharynx, larynx and hypopharynx treated with concomitant boost radiation therapy by VMAT.
Materials and methods
In this study, 30 patients of stages II–IVA disease were treated with concomitant boost radiation therapy using VMAT and those with stages III and IV also received concurrent chemotherapy with cisplatin 100 mg/m2 weekly thrice for two cycles. The total dose was 68·4 Gy/40 fractions/5.5 weeks (1·8 Gy/fraction/day to the large field for 28 fractions +1·5 Gy/fraction/day to boost field for the last 12 days of treatment). Radiation Therapy Oncology Group acute radiation morbidity scoring criteria was used to grade acute effects.
All patients completed scheduled treatment with median duration of 44 days. No grade 4 skin and mucosal toxicities were observed; grade 3 skin and mucosal toxicities seen in six (20%) and eight (26·67%) patients, respectively; grade 3 dysphagia and laryngeal toxicity in eight (26·67%) and three (10%) patients, respectively; two patients had grade 4 laryngeal toxicity. No grade 3 or grade 4 haematological toxicities were seen.
VMAT-based concomitant boost radiation therapy allows for dose escalation with good patient tolerance by limiting acute toxicities.
Multi–frequency Observations of Solar Microwave bursts recorded during solar maximum period 1980–81 are analysed and compared with x–ray data for studying the nature of microwave emissions from active regions. Most of the microwave burst spectra showed that the spectral index below the peak frequency is always less than 2.
The magneto-ionic conditions of the burst sources and the electron energies as obtained from these multi-frequency observations of the bursts showed that the centimetric and x-ray observations are satisfactorily explained, if the emitting regions are dense, hot and compact associated with strong magnetic fields of a few hundred gauss, suggesting that the thermal gyroresonance process is the most likely emission mechanism involved in the emission of microwave and x-ray radiations from the active regions of sun.
Difficult terrain and inclement weather limit our knowledge of large predators, such as the tiger Panthera tigris, in the Himalayas. A lack of empirical data on large carnivores can lead to mismanagement of protected areas and population declines. We used non-invasive genetic and remote sensing data to inform the management of such high-altitude protected areas. We used the tiger as a focal species to investigate prey preference and habitat suitability in India's Buxa Tiger Reserve, which encompasses several eco-geographical regions in the Himalayan and subtropical zones. During 2010–2013, 909 faecal samples were collected, of which 372 were confirmed, using genetic analysis, to be of tiger origin. Fourteen prey species/groups were identified in 240 tiger faecal samples, largely dominated by goats Capra spp. (26.59%), rhesus macaques Macaca mulatta (22.22%) and cattle Bos spp. (20.63%). Considering only the wild prey species for which survey data are available, however, and frequency of occurrence of prey in faecal samples, hog deer Axis porcinus, sambar deer Rusa unicolor and spotted deer Axis axis were the most preferred prey species. Using faecal sample locations to examine the relationship between tiger presence and environmental features indicated that the niche for tigers is narrower than the available protected area: c. 62% of core protected area is suitable, of which only 17% is highly suitable for tigers. Tigers prefer dense vegetation, open forests, riverine vegetation and areas close to water sources. Faecal sample-based studies have the potential to generate data that can help us understand the ecology of elusive carnivore species inhabiting high-altitude landscapes.
A total of 326 pearl millet accessions selected for fodder traits from the world collection at ICRISAT genebank, India were evaluated in rainy, postrainy and summer seasons to identify promising sources for fodder yield. In rainy season, majority of accessions grew significantly tall, produced thick stems, long and broad leaves compared with postrainy and summer seasons. Total tillers per plant were significantly more in rainy and summer seasons than in postrainy season. Significant (P = 0.05) positive correlations were observed among all traits in all seasons except total tillers, which showed significant negative correlation with all other traits but for a few cases. Accessions of cluster 1 flowered early and produced more tillers per plant, while those of cluster 3 flowered late, grew tall, produced thick stems, more leaves per plant, which were long and broad. Promising sources identified include IP 11839 and IP 11840 for plant height and number of leaves per plant, IP 15710, IP 15735 and IP 15752 for stem thickness and leaf width, and IP 3628, IP 15285, IP 15288, IP 15302, IP 15342, IP 15351, IP 15290, IP 20347 and IP 20350 for total tillers per plant. Further testing of these sources of fodder traits at different locations will be very useful.
Radio observations play a very important role in understanding the structure of the solar atmosphere. In this paper the quiet sun component of the solar radio emission has been investigated using data obtained from the Solar Indices Bulletin, National Geophysical Data Centre. By statistical method, the quiet sun component is estimated for 84 successive basic periods containing three solar rotations each using data obtained at different frequencies. From the quiet sun component we estimate the brightness temperature in each observing frequency.