bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of technological additive TsD-12 on the properties of heat-aggressive resistant rubber for sealing elements
Authors:   Chuvash State University  of I.N. Ulyanov, Spiridoniv Ivan S. , Ushmarin Nikolay F. ,   Chuvash State University  of I.N. Ulyanov, Semenova Nadezhda A. ,   Chuvash State University  of I.N. Ulyanov, Sandalov Sergey I. ,   Chuvash State University  of I.N. Ulyanov, Koltsov Nikolay I. ,   Chuvash State University  of I.N. Ulyanov
Published: February 2021

The article presents the results of a study of the effect of the technological active additive СD-12, which is a combination of zinc salts of fatty acids, on the physical and mechanical properties and resistance to aggressive media of rubber for sealing elements of packer-anchor equipment. The rubber mixture was prepared on the basis of hydrogenated nitrile-butadiene rubber Therban 3406, vulcanizing agent Novoperox BP-40, coagents for vulcanization of zinc monomethacrylate and oligoester acrylates MGF-9 and TGM-3, antioxidants Naugard 445 and agidol-2, fillers of technical carbon P 514 and T 900, filler dispersant stearic acid, rosin softener and other ingredients. To stabilize the physical and mechanical properties of vulcanizates, uniform dispersion of rubber components, reduce viscosity and improve vulcanization properties, a technological additive CD-12 was also introduced into the rubber mixture. The rubber mixture was prepared in a laboratory SKI-3L rubber mixer at a temperature not exceeding 70 °C for 7 min. The resulting mixture was vulcanized on a PV-100-2RT-2-PCD vulcanization press at a temperature of 150 °C for 60 minutes and then further vulcanized in a thermostat at a temperature of 160 °C for 6 hours. For the obtained vulcanizates, the physical and mechanical properties and resistance to the action of aggressive media were determined according to the standards existing in the rubber industry. On the basis of a rubber mixture heat-aggressive persistent sealing elements with a hardness of 70±5 Shore A units were made. These sealing elements as part of two sets of packer-anchor equipment were tested for tightness in a casing string simulator. The tests were carried out in an environment of PMS-200 polymethylsiloxane fluid at a temperature of 150 °C, an axial load of 6 tons and a pressure of 70 MPa. It is shown that both sets of packers have passed the tests and meet the requirements. The developed rubber mixture with a hardness of 70±5 Shore A units, containing the process additive СD-12, can be used for the manufacture of sealing elements for packers used in the oil and gas industry.
The effect of carbon additives on crystal structure of coal tar pitch
Authors:   Federal Research Center on Coal and Coal Chemistry, Popova Anna N.
Published: February 2021

The work is devoted to the study of changes in the basic structural characteristics of coal tar pitch during carbonization with various carbon additives that have different textural characteristics. An industrial medium-temperature coal tar pitch with a softening temperature of 87 °C was taken as a starting material, nanosized carbon material "Kemerit", nanotubes, activated carbon, and thermally expanded graphite are considered as carbon additives. It was found in the work that the entire range of considered carbon additives significantly increases the yield of coke residue, while it was noted that a decrease in the amount of released volatile products during the destruction of pitch during its thermal transformation was observed, which is very important for carcinogenic compounds. Of the selected series of carbon additives, the maximum amount of solid residue is formed when nanostructured carbon additives (nanotubes and nanosized carbon material "Kemerit") are introduced into coal tar pitch. The structural characteristics of coal tar pitch before and after the carbonization process, as well as all carbon additives considered in the work, were investigated by the complex of X-ray diffraction methods (X-ray phase and X-ray structural methods of analysis). It was revealed that the formed carbon material, when nanotubes and Kemerite are added to coal tar pitch, is characterized by a more disordered structure when compared with the structure of individual coal tar pitch. The addition of thermally expanded graphite into coal tar pitch promotes the formation of graphite-like structures during pitch carbonization and reduces the amount of volatile carcinogenic compounds during thermal destruction to a greater extent when compared with amorphous carbon additives.
Kábítószer és kábítószer-bűnözés Afganisztánban
Authors: Dely Péter
Published: February 2021

The author provides an overview of trends and developments in drug production and related activities in Afghanistan in 2001–2014.
A bizonyítási tilalmak
Authors: Horváth Georgina
Published: February 2021

The author provides a critical overview of exclusionary rules in the hungarian criminal procedural system.
Egy bírósági tárgyalás 1947-ben
Authors: Fórizs Sándor
Published: February 2021

The author provides an overview of the Hungarian perpetrators of a trial conducted by a Soviet military tribunal in 1947.
GASTROSCOPY WITH BIOPSY AND/OR SEROLOGICAL BIOPSY AS THE PRIMARY METHOD OF DIAGNOSIS OF GASTRIC MUCOSA CONDITION
Authors: Arkhipova A. A. , Anischenko V. V. , Mirsadikov R. R.
Published: February 2021

Nowadays formal programs for screening of early cancer and precancerous conditions of the gastric mucosa exist only in Japan and South Korea, where studies of the upper gastrointestinal are carried out in people at the age of 40 and older.

Objective of the study: to assess the condition of the gastric mucosa in 40-50 year-old patients by means of determination of pepsinogen 1 and pepsinogen 2 concentration ratio, and esophagogastroduodenoscopy complemented by biopsy.

Materials and methods. The analysis included examination results of 23 patients with the diagnosis: "unspecified dyspepsia". Gender distribution of patients: women – 12, men – 11, average age 46 + 3.6 years (M + m). It was a single-stage study. All patients underwent video esophagogastroduodenoscopy. There were also taken two biopsy samples, from the antrum and the body of the stomach, for a rapid urease test, and then the patients underwent blood sampling. Inclusion criteria: patients with dyspeptic symptoms who have not been previously examined and have not received any treatment; aged 40 to 50 years; voluntary informed consent for examination, positive result of rapid urease test. Withdrawal criteria: refusal to participate in the study, duodenal ulcer.

Results. Atrophic gastritis was identified during endoscopic and morphological examination in three patients (out of 23) with gastric ulcers, but the concentration ratio of pepsinogen 1 and pepsinogen 2 was higher than 3/1.

Conclusion. Our study has shown that determination of concentration ratio of pepsinogen 1 and pepsinogen 2 in patients under 50 does not reflect the presence of atrophic changes in the mucous membrane.
TYPE OF FUNDOPLICATION FOR LAPAROSCOPICHIATAL HERNIA REPAIR, COMPLICATED BY GASTROESOPHAGEAL REFLUX DISEASE
Authors: Grintcov A. G. , Ishenko R. V. , Sovpel I. V. , Sedakov I. E. , Sovpel O. V. , Balaban V. V.
Published: February 2021

Purpose. To analyze short-term and long-term outcomes of surgical treatment of the patients with hiatal hernia complicated by gastroesophageal reflux disease, depending on the choice of fundoplication method.

Materials and methods. A retrospective analysis of the short and long-term outcomes of the treatment of 171 patients suffering hiatal hernia complicated by gastroesophageal reflux disease was performed. All patients were underwent laparoscopic hiatal hernia repair supplemented by Nissen fundoplication - 109 patients or Toupet fundoplication – 62 patients.

Results. In the Nissen fundoplication group the incidence of intraoperative complications was 9.2% (11 patients), postoperative complications – 8.3% (9 patients), dysphagia in the early postoperative period was noted in 24 (22%) patients. In 5 years after surgery, gastroesophageal reflux was observed in 6 (5.5%) patients, anatomical recurrence in 13 (11.9%) patients. Dysphagia in the late postoperative period was noted in 7.3% (8 patients). In the Toupet fun doplication group the incidence of intraoperative complications was 11.3% (7 patients), the incidence of postoperative complications was 6.5% (4 patients), functional dysphagia in the early postoperative period was noted in 8 (12.9%) patients. In 5 years after surgery, gastroesophageal reflux was observed in 8 (12.9%) patients, anatomical relapse in 13 (11.9%) patients. Persistent long-term dysphagia in the late postoperative period was noted in 2(3.2%) patients.

Findings. The choice of fundoplication method did not significantly affect on the duration of surgery, the frequency of intraoperative and postoperative complications, duration hospital stay, the incidence of early functional postoperative dysphagia, the number of unsatisfactory results in the long term period, including recurrence and dysphagia.
IS THERE A FUTURE FOR SINGLE PORT LAPAROSCOPIC SURGERY?
Authors: Galimov O. V. , Prazdnikov E. N. , Khanov V. O. , Galimov D. O.
Published: February 2021

Aim.To identify a perspectives for using a single incision laparoscopic technologies in surgery.

Materials and methods:Today we have a several questions relating to a single incision laparoscopic surgery such as the possible spectrum of their application, safety and economic efficiency. The main is: does this technologies have a perspectives in future.

In paperwas performed a retro and prospective analysis of the data of modern literature and authors own experience in surgical treatment using a single incision laparoscopic technologies.

Results:The study included 74 patients who underwent: cholecystectomy – 64 (86,5%), nephrectomy – 4 (5,4%), ovarian cyst removal – 4 (5,4%), kidney resection – 2 (2,7 %), using various kind of ports: “X-Cone Karl Storz” (28), “Covidien” (18), “PPP” (7), and 21 cases of multi-trocar access.

Conclusions:Our opinion that the perspectives for the development of single incision laparoscopy, is the further development of endoscopic devices, including robotic ones, and we believe that it will be a real future and endoscopic surgeons should be ready for this.
Surfaces of (Nearly) Dormant Comets and the Recent History of the Quadrantid Meteor Shower
Authors: Kareta Theodore , Hergenrother Carl , Reddy Vishnu , Harris Walter M.
Published: February 2021

The parent of the Quadrantid meteor shower is the inactive solar system small body (196256) 2003 EH1. EH1 has likely only gone dormant in the past few hundred years, and may be related to the bright comet C/1490 Y1. Compared with the other best-studied inactive meteor shower parent (3200) Phaethon, EH1 has received comparatively minimal characterization of its surface properties. We present the first reflectance spectrum and additional photometry of EH1, as well as new spectra of the nuclei of three nearly dormant comets P/2006 HR30 (Siding Spring), 364P/Pan-STARRS, and 249P/LINEAR for comparison. We also present new short-term high-resolution orbital integrations of these bodies for context. EH1s spectrum is red in color below 0.8 μm in between C and D types, consistent with previous photometric measurements, but is blue beyond 0.8 μm until at least 1.02 μm. 249P and 364P have both red slopes consistent with C taxonomic types and HR30 has a classic comet nucleus D-type slope. If the downturn in EH1’s spectrum is due to an absorption feature, magnetite and olivine are plausible candidates, but more data are needed. 249P and 364P have similar recent and historical dynamical evolutions in addition to their similar surface properties. We discuss the interrelation between the dynamical histories and modern surfaces of these four objects and suggest avenues for further study to better constrain how the Quadrantids and Geminids were created.
Polarimetric Decomposition of Near-Earth Asteroids Using Arecibo Radar Observations
Authors: Hickson Dylan C. , Virkki Anne K. , Perillat Phil , Nolan Michael C. , Bhiravarasu Sriram S.
Published: February 2021

The polarization state of radar echoes from planetary bodies contains information about the scattering mechanisms present on the surface and thus the near-surface physical properties. Polarimetric radar scatter from complex surfaces, such as those observed for spacecraft-visited near-Earth asteroids (NEAs), is not well understood in terms of relating observed polarimetry to surface properties. Here we present an improved methodology for polarimetric analyses of ground-based radar observations of NEAs, extending techniques derived for larger bodies. We calculate the Stokes vector for delay-Doppler images of NEAs and use this to perform the m-chi decomposition and derive polarimetric products such as the degree of polarization, circular polarization ratio, and degree of linear polarization. We apply this methodology to radar observations of NEAs (53319) 1999 JM8, (101955) Bennu, and (33342) 1998 WT24 obtained by the Arecibo Observatory. We also perform numerical simulations of the m-chi decomposition for irregular boulders to augment the interpretation of the results for NEAs. Our analyses show that significant components of radar echoes are depolarized (random polarization) and linearly polarized. The numerical simulations confirm that depolarization is increased by single scattering from nonspherical wavelength-scale particles. Our analysis suggests that 1999 JM8 is possibly covered in regolith and that surface scatterers dominate the scattering properties of Bennu. The NEA 1998 WT24 displays diverse polarimetric properties, which we reconcile with optical and thermal observations by assuming a fine-grained regolith mantling a rugged, dense interior. In this work, we demonstrate the usefulness of radar polarimetry in characterizing the physical properties of planetary surfaces.
The synthesis and the antioxidant activity of 1-phenoxymethyl-4-aryl-5,6,7,8-tetrahydro-2a,4a,8a-triazacyclopenta[cd]azulene-3-carboxylic (or carbothionic) acid derivatives
Authors: Demchenko Sergii , Yeromina Hanna , Fedchenkova Yulia , Ieromina Zinaida , Yaremenko Vitaliy , Vislous Olha , Perekhoda Lina , Demchenko Anatolii
Published: February 2021

New 1-phenoxymethyl-4-aryl-5,6,7,8-tetrahydro-2а,4a,8a-triazacyclopenta[cd]azulene-3-carboxylic (or carbothionic) acid derivatives have been designed, synthesized and evaluated for their in vitro antioxidant activity under conditions of the artificial oxidative stress using ionol, ascorbic acid and α-tocopherol as the reference drugs. It has been found that 1-phenoxymethyl-4-aryl-5,6,7,8-tetrahydro-2а,4a,8a-triazacyclopenta[cd]azulene-3-carbothionic acid derivatives 9b, 9c, 9d, 9e, 9f, 9i and 1-phenoxymethyl-4-(41-chlorophenyl)-5,6,7,8-tetrahydro-2,2a,8-triazacyclopenta[cd]azulene-3-carboxylic acid phenylamide 10 reveal a high antioxidant activity and a good in silico pharmacokinetic profile. The data obtained allowed us to select the most promising objects from the substances synthesized for further pharmacological screening for the presence of the antioxidant activity in vivo.
Review of the Neotropical water scavenger beetle genus Tobochares Short & García, 2007 (Coleoptera, Hydrophilidae, Acidocerinae): new lineages, new species, and new records
Authors: Girón Jennifer C. , Short Andrew Edward Z.
Published: February 2021

The water scavenger beetle genus Tobochares Short & García, 2007 currently contains ten species, including one known but formally undescribed taxon. Although Tobochares was revised in 2017, ongoing fieldwork as well as an expanded concept of the genus has led to the recognition of numerous additional species. Here a combination of morphological and molecular data is presented to review this newly found Tobochares diversity. Fifteen new species are described from South America, bringing the total number of known species to 25: Tobochares akoeriosp. nov. (Suriname), T. arawaksp. nov. (Guyana), T. anthonyaesp. nov. (Venezuela: Bolívar), T. aturessp. nov., (Venezuela: Amazonas), T. benettiisp. nov. (Brazil: Amazonas), T. canaimasp. nov. (Venezuela: Bolívar), T. communissp. nov. (Brazil: Amapá and Roraima, Guyana, Suriname, Venezuela: Bolívar), T. fusussp. nov. (Brazil: Amapá, French Guiana), T. goiassp. nov. (Brazil: Goiás), T. kappelsp. nov. (Suriname), T. kolokoesp. nov. (Suriname), T. luteomargosp. nov. (Venezuela: Bolívar), T. micropssp. nov. (Suriname), T. pemonsp. nov. (Venezuela: Bolívar), and T. romanoaesp. nov. (Brazil: Roraima). Both morphological and molecular analyses support four clades within the genus, which are here diagnosed and described as species groups. New distributional records are provided for T. kusad Kohlenberg & Short, 2017 and T. sipaliwini Short & Kadosoe, 2011, both of which are recorded from Brazil for the first time. Previously restricted to the Guiana Shield region of South America, the distributional range of the genus is now broadly expanded to include localities as far south as the central Brazilian state of Goiás. Consistent with the biology of the previously described species, almost all the new species described here are associated with seepage and wet rock habitats. Remarkably, one species, T. fusussp. nov., was collected in both seepage habitats as well as in the rotting fruits of Clusia Linnaeus (Clusiaceae), making it one of the few known acidocerines with terrestrial habits outside of the genus Quadriops Hansen, 1999. High-resolution images of most species are included, as well as a key to species groups, species, and habitat photographs.
Four new West Palaearctic species and new distributional records of Hybotidae (Diptera)
Authors: Kanavalová Liliana , Grootaert Patrick , Kubík Štěpán , Barták Miroslav
Published: February 2021

Megagrapha starkiBarták & Grootaert,sp. nov.(Poland, Russia, Slovakia),Oedalea portugalicaBarták & Grootaert,sp. nov.(Portugal),Hybos conicusGrootaert & Barták,sp. nov.(Greece, Turkey), andPlatypalpus obscuroidesBarták & Grootaert,sp. nov.(Slovakia) are described and illustrated. Diagnostic characters are discussed. The female ofSyndyas merziShamshev & Grootaert, 2012 is described for the first time. New distributional records are presented:Megagrapha europaeaPapp & Földvári, 2001 is first reported from Slovakia andSyndyas merziShamshev & Grootaert, 2012 is first reported from Turkey.
MOLT: A Mobile Learning Tool That Makes Learning New Technical English Language Words Enjoyable
Authors: Ibrahim Dogan - , Cavus Nadire
Published: February 2021

There is an increase use of wireless technologies in education all over the world. In fact, wireless technologies such as laptop computers, palmtop computers, and mobile phones are revolutionizing education and transforming the traditional classroom based learning and teaching into anytime and anywhere education. This paper investigates the use of wireless technologies in education with particular reference to the potential of learning new technical English Language words using SMS text messaging. The system, developed by the authors, called Mobile Learning Tool (MOLT), has been tested with 45 first-year undergraduate students. Studentsâ?? opinions have been collected after the experiment. Our results show that students enjoyed and be happy used mobile phones to learn new technical English word. We believe that if we add the improvements or modifications students wish to see in the MOLT system, then using the MOLT system as an educational tool will contribute to motivation and success of students.
mLearning, the First Step in Learning Process Revolution
Authors: Conde González Miguel
Published: February 2021

The learning process is subject to continuous changes due to the changing needs of users. These changes are most often accompanied by new technologies which are constantly appearing in our modern computerized society. The Internet has allowed the optimization of the learning process through supported learning platforms, in addition to this, the dissemination of mobile devices such as P.D.A.´s allows for a new stage in this process, mLearning. This is based on the ability of the user to access their course information at any time and place without the restriction of needing to have a computer in their possession, this along with other characteristics will determine the direction of ubiquitous learning.
Long-term effect of acidic pH on the surface microhardness of ProRoot mineral trioxide aggregate, Biodentine, and total fill root repair material putty
Authors: Bayraktar Koral , Basturk Fatima Betul , Turkaydin Dilek , Gunday Mahir
Published: February 2021

Background:

The purpose of this study was to compare the microhardness values of ProRoot mineral trioxide aggregate (MTA), Biodentine, and total fill root repair material (TF-RRM) Putty at varying pH and times.

Materials and Methods:

In this laboratory experiment, materials were mixed and placed in cylinder blocks with internal dimensions of 6 mm × 4 mm. Ten samples of each material were soaked in buffered solutions of butyric acid with 4.4, 5.4, 6.4, and 7.4 pH values and stored at 37°C in 100% humidity. The samples were submitted to the microhardness test at the end of 1 week and then 1 month. Multivariate analysis of variance and Tukey honestly significant difference tests were carried out to compare the mean values at a significance level of P < 0.05.

Results:

Low pH caused a significant decrease in the microhardness values of all samples. Surface microhardness increased with time (P < 0.0001). The microhardness values of Biodentine were significantly greater than those of ProRoot MTA and TF-RRM putty (P < 0.0001). The lowest microhardness values were recorded for TF-RRM putty groups regardless of the pH of the environment and the evaluation time.

Conclusion:

An acidic environment impaired the surface microhardness of all root repair materials tested. Overall, the mean surface microhardness of TF-RRM Putty was lower than those of ProRoot MTA and Biodentine. Biodentine showed the greatest microhardness values at all pH values, regardless of the evaluation time.
Oral manifestations in inflammatory bowel disease
Authors: Khozeimeh Faezeh , Shakerin Hadi , Daghaghzadeh Hamed , Najarzadegan Fereshteh , Golestannejad Zahra , Adibi Peyman
Published: February 2021

Background:

Various systemic diseases can cause oral manifestations, such as inflammatory bowel disease (IBD). This study is designed to investigate the frequency of oral manifestations in patients with IBD referred to health centers and offices in Isfahan in 2018.

Materials and Methods:

This cross-sectional study was done among 161 patients suffering from IBD in Isfahan, Iran. They were chosen by the systematic randomized sampling. Finally, the data were analyzed using the logistic regression test in the SPSS software. Significance was assigned at P < 0.05.

Results:

The number of patients with ulcerative colitis and Crohn's syndrome was, respectively, 119 persons (73.9%) and 42 persons (26.1%). Oral manifestations were seen among 52 (32.3%) of the samples. The frequency of oral manifestations was 35.6% (31 cases) in males and 28.4% (21 cases) in females. Oral manifestations were seen in 29.4% of patients with ulcerative colitis and 40.5% of patients with Crohn's disease. Based on the logistic regression, there was a statistically significant relationship between the use of azathioprine and mesalazine with oral manifestations (P < 0.05), whereas the severity of disease and smoking were not statistically significantly related to oral manifestations (P > 0.05).

Conclusion:

The severity of the disease was not significantly correlated with oral manifestations, which are in agreement with the results of previous studies. It was also found that among patients with IBD, the oral aphthous ulcers can appear 1–3 years before the diagnosis of the disease. Besides that, some of the drugs used to treat the disease have a significant relationship with oral manifestations.
Relationship of pH and the viscosity of five different iron supplements with the absorption of iron ions and enamel discoloration in the anterior primary teeth (an in vitro study)
Authors: Babaei Navid , Molaei Tina , Belyad Saeid , Hekmatfar Somayeh
Published: February 2021

Background:

Various iron drops are prescribed to children to prevent iron-deficiency anemia. The current study aimed to evaluate and compare the physicochemical profile of iron drops and the effect of these medicines on the color of primary teeth.

Materials and Methods:

On the commencement of this experimental study, the pH and viscosity of five types of iron drops were measured. For the purpose of the current study, sixty healthy anterior deciduous teeth were provided; thereafter, they were assigned to five groups and then exposed to iron drops. The color and color difference of each specimen were measured by VİTA Easyshade Compact after 2 weeks. The amount of absorbed iron was determined by atomic absorption. The data were analyzed using two-way ANOVA and Tukey's test (P < 0.05).

Results:

As evidenced by the obtained results, all medications demonstrated acidic pH and discoloration. The viscosity values of iron drops were reported to be within the range of 2.07–33.58 cP. Based on the results of Pearson's correlation coefficient test, discoloration showed a correlation with pH and atomic absorption (P < 0.05).

Conclusion:

Analyzed iron drops displayed low pH and discoloration higher than 3.3 which can be easily distinguished with naked eyes. Medicine labels should include warning statements on the feasibility of dental discoloration and erosion.
Effect of different surface treatment with panaviaV5 on shear bond strength of metal brackets to silver amalgam
Authors: Alavi Shiva , Shirani Farzaneh , Zarei Zahra , Raji Seyed Amir Hossein
Published: February 2021

Background:

This study was conducted to compare the shear bond strength (SBS) of orthodontic brackets to amalgam surfaces by two surface treatment methods, two different adhesives, and one intermediate resin and also to evaluate surface roughness after two preparation methods as well as bond failure mode.

Materials and Methods:

In this in-vitro study forty-eight amalgam samples were randomly allocated to four groups. In Groups 1–3, specimens were sandblasted with 50 μm aluminum oxide, followed by application of Alloy primer in Groups 1 and 2. In Group 3 Alloy primer had not used. In Group 4, samples were prepared by silica coating using a silane coupling agent. Surface roughness analysis was performed in 10 additional samples after two surface treatments. The brackets in Group 1 were bonded with Transbond XT and those in other groups were bonded with Panavia V5. All specimens were examined for SBS following 5000 times thermocycling at 5°C–50°C. Modified adhesive remnant index was utilized for the bond failure mode. Data analysis was done by one-way analysis of variance, post hoc Tukey, Kruskal–Walli and Mann–Whitney U tests. Statistical significance was set at P < 0.05.

Results:

The findings indicated the mean SBS were low (ranged from 0.19 to 4.66 MPa) and significantly lower in Group 3 than in Group 4 (P = 0.009). Bond failure occurred in adhesive/amalgam interface in nearly all samples. Silica coating produced significantly lower roughness than sandblast (P = 0.009).

Conclusion:

Silica coating had a significant higher bond strength than sandblast without application of Alloy primer. However compared to sandblast with Alloy primer, silica coating did not significantly improve the bond strength. Chemical bond between PanaviaV5 and sandblasted amalgam was not considerable.
The impact of surgery on the survival of patients with recurrent glioblastoma
Authors: Sacko Oumar , Benouaich-Amiel Alexandra , Brandicourt Pierre , Niaré Mahamadou , Charni Saloua , Cavandoli Clarissa , Brauge David , Catalaa Isabelle , Brenner Adam , Moyal Elizabeth , Roux Franck-Emmanuel
Published: February 2021

Objective: The purpose of this study was to investigate the possible benefit of repeat surgery on overall survival for patients with recurrent glioblastoma multiforme (GBM). Methods: We performed a retrospective analysis of data from patients who presented with recurrent GBM over a 5-year period (n = 157), comparing baseline characteristics and survival for patients who had at least 1 new tumor resection followed by chemotherapy (reoperation group, n = 59) and those who received medical treatment only (no-reoperation group, n = 98) for recurrence. Results: The baseline characteristics of the two groups differed in terms of WHO performance status (better in the reoperation group), mean age (60 years in the reoperation group vs. 65 years in the no-reoperation group), mean interval to recurrence (3 months later in the reoperation group than in the no-reoperation group) and more gross total resections in the reoperation group. Nevertheless, the patients in the reoperation group had a higher rate [32.8%] of sensorimotor deficits than those of the no-reoperation group [14.2]. There was no significant difference in sex; tumor localization, side, or extent; MGMT status; MIB-1 labeling index; or Karnofsky Performance Status [KPS] score. After adjustment for age, the WHO performance status, interval of recurrence, and extent of resection at the first operation, multivariate analysis showed that median survival was significantly better in the reoperation group than in the no-reoperation group (22.9 vs. 14.61 months, P < 0.05). After a total of 69 repeat operations in 59 patients (10 had 2 repeat surgeries), we noted 13 temporary and 20 permanent adverse postoperative events, yielding a permanent complication rate of 28.99% (20/69). There was also a statistically significant (P = 0.029, Student's t-test) decrease in the mean KPS score after reoperation (mean preoperative KPS score of 89.34 vs. mean postoperative score of 84.91). Conclusion: Our retrospective study suggests that repeat surgery may be beneficial for patients with GBM recurrence who have good functional status (WHO performance status 0 and 1), although the potential benefits must be weighed against the risk of permanent complications, which occurred in almost 30% of the patients who underwent repeat resection in this series.
Epithelioid sarcoma of lumbar spine: A rare mesenchymal tumor masquerading as infection
Authors: Sudhir G , Jayabalan S , Ram Amith , Gadde Saikrishna , Kailash Karthik
Published: February 2021

Epithelioid sarcoma of the spine has been rarely reported in the literature. Its diagnosis is challenging due to nonspecific findings. We report a case of 42-year-old gentleman with back pain. Magnetic resonance imaging (MRI) revealed lesion in the L4 vertebral body extending into the spinal canal with pre and paravertebral involvement. He underwent posterior spinal decompression and instrumentation with biopsy. Histopathological examination was nonspecific. Considering clinical and radiological features, antitubercular treatment was initiated. The patient developed acute onset weakness of both lower extremities 1 month post-surgery. Repeat MRI and positron emission tomography (PET) computed tomography revealed an increase in the extent of lesion which required revision decompression. Histopathological examination showed cells with epithelioid appearance, positive for Vimentin, and epitheloid membrane antigen in immunohistochemistry. Radiotherapy was planned but the patient expired due to multiorgan dysfunction. Epithelioid sarcomas are rare soft-tissue neoplasms with poor prognosis. They can mimic infection and a high degree of suspicion is required in these cases to diagnose and treat them early.
A systematic review on the impact of the COVID-19 pandemic on neurosurgical practice and Indian Perspective
Authors: Sadhasivam Saravanan , Arora Rajnish , Rekapalli Rajasekhar , Chaturvedi Jitender , Goyal Nishant , Bhargava Pranshu , Mittal Radhey
Published: February 2021

Objective: The study objective was to systematically review the impact of the current pandemic on neurosurgical practice and to find out a safe way of practicing neurosurgery amid the highly infectious patients with COVID-19. Materials and Methods: A review of the PubMed and EMBASE databases was performed. The literature was systematically searched using keywords such as “COVID-19” and “Neurosurgery.” Results: Among the 425 records, 128 articles were found to be eligible for analysis. These articles described the perspectives of the neurosurgical departments during the pandemic, departmental models, and organizational schemes for triaging emergent and nonemergent neurosurgical cases for the optimal utilization of limited resources, and solutions to continue academic and research activities. Triaging systems help us to optimally utilize the limited resources available. Guidelines have been developed for safe neurosurgical practice and for the continuation of clinical and academic activities during this pandemic by various national and international neurosurgical societies. Key changes in the telemedicine regulatory guidelines would help us to continue to provide neurosurgical care. Videoconferences, online education programs, and webinars could help us to overcome the disadvantages brought upon the neurosurgical education by the social-distancing norms. Conclusion: In an unprecedented time like this, no single algorithm is going to clear the ethical dilemma faced by us. Individual patient triage is a way for maintaining our ethical practice and at the same time, for efficiently utilizing the limited resources. As the pandemic progresses, new guidelines and protocols will continue to evolve for better neurosurgical practice.
Optimizing Anticancer Therapy in Newly Diagnosed Metastatic Castration Sensitive Prostate Cancer
Authors: Thanos Anastasios
Published: February 2021

Historically, androgen deprivation therapy has been the standard of care in the management of metastatic castration sensitive prostate cancer (mCSPC). However, during the past 5 years, numerous different treatment options have become available and have been set under investigation. The addition of docetaxel or abiraterone acetate has improved outcomes for patients with mCSPC and has become a new standard of care. New drugs targeting androgen receptor axis, local therapy including surgery, radiotherapy, and brachytherapy as well as metastatic-directed treatments have also demonstrated promising outcomes. In this work, the available data on all treatment modalities employed in mCSPC are being reviewed.
Nevus Unius Lateris with Bilateral Oral Mucosal Lesions
Authors: Kaur Lovleen , Mahajan Bharat B. , Mahajan Mohita , Dhillon Shaminder Singh
Published: February 2021

Verrucous epidermal nevi (VEN) are cutaneous hamartomas characterized by keratinocytic hyperplasia. Majority are linear in distribution and tend to follow the Blaschko lines; however, some may have zosteriform (segmental) or systematized distribution involving widespread areas of skin. The systematized ones are further classified into “Nevus Unius Lateris” when one-half of the body is affected, and “Ichthyosis Hystrix” showing bilateral distribution, both being the uncommon forms. Although it can affect any body part, it rarely involves the head and neck region with seldom involvement of mucosae, scalp, and ear lobes. We saw a 6-year-old child with multiple hyperpigmented verrucous plaques predominantly present over left half of the body, ipsilateral alopecia scalp, and verrucous lesions involving mucosae of palate and tongue, which were present bilaterally. Previously, case reports of oral lesions related to VEN had demonstrated segmental, midline, or unilateral distribution. Hereby, we report this peculiar case of Nevus Unius Lateris with bilateral oral mucosal involvement, owing to its rarity.
Mycetoma due to Nocardia Africana/Nova Treated Successfully with Cotrimoxazole and Moxifloxacin
Authors: Bhandari Molisha , Kathuria Sushruta , Khunger Niti , Sharma Bhawna
Published: February 2021

Nocardia africana is a recently identified organism and has rarely been reported to cause mycetoma. Here we report the case of a 40-year-old woman who presented with discharging sinuses and nodules for the past 7 years along with few discrete axillary lymph nodes. Cultures and Maldi-TOF MS (Matrix-assisted laser desorption/ionization–time of flight mass spectrometry) method identified the causative organism as Nocardia africana/nova. The organism was acid-fast positive on modified Ziehl-Neelsen stain and Gram's stain revealed branched filamentous beaded gram-positive bacilli, while histopathology showed granulation tissue along with few ill-defined epithelioid cell granulomas, with giant cells. Based on the sensitivity report, the patient was started on tablet moxifloxacin and cotrimoxazole, and has shown considerable improvement at 2.5 months of follow-up.
Laparoscopic transabdominal preperitoneal repair in the management of Spiegelian hernia – A three-patient case series and review of the literature
Authors: Alpuche Héctor Alí Valenzuela
Published: February 2021

BACKGROUND:

Spiegel hernia (SH) is a rare type of primary ventral hernia. Surgery has been performed by open or minimally invasive means with no current gold standard due to a shortage of current evidence. We advocate for the transabdominal preperitoneal approach (TAPP) for its cost effective outcome. We present a series of 3 cases operated using the TAPP approach in the past 5 years, carried out by a single surgeon, and a review of the literature.

METHODS:

A retrospective analysis of a case series of 3 patients' operations between January 2015 and June 2020. TAPP repair was found to be a safe and effective anatomical repair with all the added benefits of laparoscopic surgery such as reduced hospital stay, quicker recovery, and fewer surgical site occurrences.

CONCLUSIONS:

Several operative techniques have been described to repair Spiegel hernia but in our particular practice we felt laparoscopic TAPP approach was the safest and with a more predictable outcome due to the authors familiarity with it.
Robotic transabdominal preperitoneal repair of complex inguinal hernias
Authors: Kudsi Omar Yusef , Bou-Ayash Naseem , Gokcal Fahri
Published: February 2021

BACKGROUND:

Complex inguinal hernia repairs (IHR) have been defined based on previous relative contraindications for their minimally invasive repair. In this study, we aim to describe outcomes after complex robotic IHR (rIHR) and the associated challenges.

MATERIALS AND METHODS:

A retrospective analysis was performed of patients who underwent complex rIHR in an elective setting between 2013 and 2020. Patients included into the study were those with a recurrence after posterior IHR, history of prostatectomy, large scrotal hernia, or irreducible hernia after anesthesia induction (incarcerated). Any patients with concomitant procedures or emergent repairs were excluded. Complications were assessed with the Clavien-Dindo (CD) and Comprehensive Complication Index (CCI®) scoring systems.

RESULTS:

A total of 88 patients were identified. Accounting for bilateral IHRs, the total number of complex rIHRs was 110. Although there were no conversions to an open approach, one patient required a hybrid procedure. The average length of stay (LOS) and follow-up period were 0.2 days and 33 months, respectively. A total of four major complications (CD-Grade III/IV) were observed. These included three seromas requiring drainage, one of which necessitated readmission, and 1 postoperative intensive care unit admission. No chronic pain or recurrence was observed. The CCI® scores were ranged between 0 and 42.4. In a univariate analysis, no statistically significant variable was found between patients with and without postoperative complications.

CONCLUSION:

Complex rIHR may be performed with minimal LOS, complications, and adverse long-term sequelae. A patient-tailored approach and adequate surgical training and knowledge are essential to attempt these procedures.
Abdominal intercostal hernia repair
Authors: Li Junsheng , Shao Xiangyu , Cheng Tao
Published: February 2021

Abdominal intercostal hernia (AIH) is a rare disease, may occur secondary to trauma or previous surgery, recently. There is no consensus on the best treatment of AIH. The aim of the present study is to report the repair of AIH in a male patient. The AIH in a 56-year-old male was repaired with the laparoscopic procedure; the patient characteristics and repair details were described. The computed tomography scan revealed an intercostal hernia containing omentum between the 9th rib and 10th rib. The laparoscopic repair with synthetic mesh was successfully performed, and the patients were absent of symptoms at 8-month follow-up. There is no consensus on the best treatment of AIH, tension-free prosthetic repair is recommended, and the laparoscopic approach has several advantages for AIH repair.
Long-term results of Progrip mesh for retromuscular repair of ventral hernia
Authors: Eltyeb Hazim A. , Dowker Frederick , Light Duncan
Published: February 2021

BACKGROUND:

An issue that has become apparent in using Progrip in ventral hernias is the restriction in the available sizes. The area of dissection for mesh placement can be variable. This report is based on a subgroup analysis of the cases in which a combination of Progrip meshes was used.

MATERIALS AND METHODS:

This was a retrospective review of our prospective database. Cases were identified of Progrip mesh used in ventral hernia repair from 2016 to 2020. Subgroup analysis was performed of cases which Progrip meshes were combined. Telephone follow-up was done in September 2020.

RESULTS:

Sixty-eight cases were identified. The mean age of patients was 63.13 (26–87). Thirty-three were female. The mean American Society of Anesthesiologists grade was 2 (range: 1–4). The procedure time was 164.35 min (45–490). The mean defect size was 7.23 (2–25 cm). The mean mesh size was a 20 cm × 15 cm mesh. Follow-up was achieved in 63/68 cases. Follow-up ranged from 1 to 4 years. Recurrence was found in 4 (6%). Nine had ongoing abdominal pain. Fifty-nine (93.65%) returned to normal activity. Three returned to theater for wound dehiscence and seromas. Twelve cases required 2 meshes to be combined. All cases involved a mesh size of 30 cm × 30 cm. The mean age was 64 (44–78 years). Six were male. The mean defect size was 9 cm. The operative time was 235 min (120–320). The mean postoperative stay was 5 days (4–60). Three cases required component separation (2 anterior component separation and 1 posterior component separation). There were no recurrences or further surgery. One had ongoing pain. Nine cases had full return to activity.

CONCLUSION:

Combining Progrip meshes in ventral hernia is an acceptable practice. Mesh may be sutured together or overlapped with equivalent results. Extending the product range to a 30 cm × 30 cm mesh would obviate the need for mesh overlap in our practice.
Validación de la estrategia Aprendizaje Basado en el Diseño (ABED) en el contexto de la Educación Rural en Chile
Authors: Palma Maritza Roxana , Navarrete Eliana Lucia
Published: February 2021

Actualmente en Chile, las aulas multigrado del sector rural presentan una baja eficiencia en los procesos de enseñanza y aprendizaje. Esta debilidad supone la implementación de nuevas metodologías, donde los estudiantes adquieren un papel activo en el proceso de formación escolar. La finalidad del estudio fue develar las percepciones de la comunidad educativa de las escuelas rurales de las regiones de Ñuble y Los Lagos para validar el modelo didáctico ABED. El estudio fue de corte cualitativo, siguiendo los principios de la teoría fundamentada. Los datos provenientes de las entrevistas evidencian la capacidad del modelo ABED para integrar los Objetivos de Aprendizaje Transversales de manera natural y su enfoque inclusivo. Asimismo, en el discurso de los diferentes actores, se valora la experiencia ABED, en base a una enseñanza centrada en las personas, la motivación, la creatividad y la contextualización de sus aprendizajes, desarrollando habilidades para una sociedad globalizada.
Relación funcional entre procrastinación académica y compromiso en estudiantes de educación superior: una propuesta de análisis
Authors: ASPEÉ JUAN , GONZÁLEZ JOSÉ , HERRERA YUDI
Published: February 2021

El compromiso estudiantil es el involucramiento del estudiante en su proceso formativo, para lo cual destina tiempo y energía a dicho proceso, mientras que la procrastinación en estudiantes implica aplazar la ejecución de los deberes y acciones del proceso formativo. Este estudio propone un modelo de relación funcional entre estos fenómenos. Dicha relación se aplica en una muestra de 412 estudiantes de una universidad regional chilena. Así, la mayor parte de los estudiantes se encuentran en el rango bajo y muy bajo de procrastinación (71,60% de la muestra). Los resultados evidencian que, si bien procrastinación y compromiso académico demuestran estar relacionados inversamente, no son estrictamente antagónicos. Asimismo, los niveles de procrastinación se muestran refractarios a los factores personales y de contexto, lo que lleva a la necesidad de analizar los factores psicológicos involucrados y de escudriñar nuevas relaciones entre el compromiso y la procrastinación académica.
Debilidad en la relación familia-escuela, evidencias desde la mirada de futuros docentes
Authors: Cárcamo Héctor , Jarpa-Arriagada Carmen
Published: February 2021

El objetivo es develar las representaciones que poseen los futuros profesores de educación primaria respecto de la implicación de las familias en el proceso de escolarización de niños y niñas. El estudio se realiza en dos regiones del centro-sur de Chile. Corresponde a una investigación cualitativa en la que se entrevistó a 40 estudiantes de pedagogía. Se aplica análisis semántico-estructural con base a tres categorías deductivas: naturaleza, nivel y espacio de implicación parental. Fruto del análisis se constata que las representaciones que tienen los futuros profesores se sustentan sobre una implicación parental fundada en la lógica de consumidor, valorando a aquellas familias que buscan informarse y colaborar con lo que la escuela demanda, especialmente cuando dicha colaboración es desde el hogar. Es fundamental problematizar desde la formación inicial docente la relación familia y escuela con el fin de proporcionar insumos para la reconfiguración de estas representaciones.
¿Cómo es el trabajo de los profesores de educación básica en tiempos de pandemia? Modalidades de aprendizaje y percepción del profesorado chileno sobre la educación a distancia
Authors: Villalobos Muñoz Katherine Daniela
Published: February 2021

La suspensión de clases presenciales a causa del COVID-19 ha supuesto uno de los mayores desafíos al transitar a una educación a distancia, lo que ha llevado a los colegios a implementar diferentes estrategias y recursos para dar continuidad al aprendizaje. A través de una metodología mixta, este estudio buscó indagar en la modalidad de trabajo y percepción del profesorado de primer ciclo de Chile sobre la educación remota. Se divulgó por correo electrónico una encuesta al profesorado del que se obtuvo 618 respuestas. Los resultados de este instrumento muestran diferencias en el tiempo de interacción síncrona y similitudes en las estrategias de enseñanza. Se detectan preocupaciones del profesorado sobre la efectividad en el aprendizaje, el acceso desigual a internet y la elevada sobrecarga laboral. Se discuten las diferencias en el acceso a las tecnologías y en la valorización del docente como sujeto mediador y de constante aprendizaje.