185 research outputs found
Hearing Loss in Patients with Nasopharyngeal Carcinoma after Chemotherapy and Radiation
In light of the possible adverse effects of radiation on hearing, we conducted a study to evaluate the long-term sensorineural hearing status following radiotherapy (RT) in patients suffering from nasopharyngeal carcinoma. Audiologic examinations were performed at regular intervals before and after RT. We also analyzed the effects of age, chemotherapy, pre-RT hearing status, and post-RT otitis media with effusion (OME) on post-RT hearing change. A total of 150 patients (261 ears) were enrolled in this study and followed up for a mean of 43.8 months. After RT, 8.9-28.8% of ears had at least a 10 dB loss in bone conduction threshold at speech frequency, which was defined as an average of hearing threshold at 0.5 kHz, 1 kHz, and 2 kHz, while the percentage was 18-34.2% at 4 kHz. Patient age was related to these changes at speech frequency, and the presence of post-RT OME was related to significant loss at both speech frequency and 4 kHz. Pre-RT hearing status and chemotherapy did not influence hearing change. To sum up, sensorineural hearing loss began as early as after completion of RT. Early changes may be transient, but the effect of radiation on hearing tended to be chronic and progressive
Cerebral Radionecrosis with Cystic Degeneration Following Radiotherapy for Nasal Cavity Squamous Cell Carcinoma: A Case Report
A 31-year-old man with nasal cavity squamous cell carcinoma was treated in our hospital with two courses of radiotherapy (120 Gy total dose) followed by surgical tumor resection. Three years after the last irradiation, he developed seizures as well as changes in behavior and consciousness. Medical therapy with diphenylhydantoin (Dilantin(r)) terminated the seizures. Dysphagia, unsteady gait, and right-side limb weakness developed 37 months after the onset of seizures. Magnetic resonance imaging showed a large, cystic mass in the left temporal lobe with left to right midline shift. Following craniotomy with decompression of the cystic mass, the patient improved clinically. No malignant cells were found in the specimen. No further progression of neurologic symptoms was noted after a 1-year follow-up. Cerebral radionecrosis is an uncommon late complication of radiotherapy and needs to be differentiated from tumor recurrence or metastasis if the irradiation field covers the cerebral region in patients with head and neck malignancies
Anatomical Variations of Recurrent Laryngeal Nerve During Thyroid Surgery: How to Identify and Handle the Variations With Intraoperative Neuromonitoring
Recurrent laryngeal nerve (RLN) palsy is the most common and serious complication after thyroid surgery. Visual identification of the RLN during thyroid surgery has been shown to be associated with lower rates of palsy, and although it has been recommended as the gold standard for RLN treatment, it does not guarantee success against postoperative vocal cord paralysis. Anatomical variations of the RLN, such as extra-laryngeal branches, distorted RLN, intertwining between branches of the RLN and inferior thyroid artery, and non-recurrent laryngeal nerve, can be a potential cause of nerve injury due to visual misidentification. Therefore, intraoperative verification of functional and anatomical RLN integrity is a prerequisite for a safe thyroid operation. In this article, we review the literature and demonstrate how to identify and handle the anatomical variations of the RLN with the application of intraoperative neuromonitoring in the form of high resolution photography, which can be informative for thyroid surgeons. Anatomical variations of the RLN cannot be predicted preoperatively and might be associated with higher rates of RLN injury. The RLN injury caused by visual misidentification can be rare if the nerve is definitely identified early with intraoperative neuromonitoring
The photometric observation of the quasi-simultaneous mutual eclipse and occultation between Europa and Ganymede on 22 August 2021
Mutual events (MEs) are eclipses and occultations among planetary natural
satellites. Most of the time, eclipses and occultations occur separately.
However, the same satellite pair will exhibit an eclipse and an occultation
quasi-simultaneously under particular orbital configurations. This kind of rare
event is termed as a quasi-simultaneous mutual event (QSME). During the 2021
campaign of mutual events of jovian satellites, we observed a QSME between
Europa and Ganymede. The present study aims to describe and study the event in
detail. We observed the QSME with a CCD camera attached to a 300-mm telescope
at the Hong Kong Space Museum Sai Kung iObservatory. We obtained the combined
flux of Europa and Ganymede from aperture photometry. A geometric model was
developed to explain the light curve observed. Our results are compared with
theoretical predictions (O-C). We found that our simple geometric model can
explain the QSME fairly accurately, and the QSME light curve is a superposition
of the light curves of an eclipse and an occultation. Notably, the observed
flux drops are within 2.6% of the theoretical predictions. The size of the
event central time O-Cs ranges from -14.4 to 43.2 s. Both O-Cs of flux drop and
timing are comparable to other studies adopting more complicated models. Given
the event rarity, model simplicity and accuracy, we encourage more observations
and analysis on QSMEs to improve Solar System ephemerides.Comment: 23 pages, 5 appendixes, 16 figures, 7 table
Polymorphism in COX-2 modifies the inverse association between Helicobacter pylori seropositivity and esophageal squamous cell carcinoma risk in Taiwan: a case control study
<p>Abstract</p> <p>Background</p> <p>Overexpression of Cyclooxygenase-2 (COX-2) was observed in many types of cancers, including esophageal squamous cell carcinoma (ESCC). One functional SNP, COX-2 -1195G/A, has been reported to mediate susceptibility of ESCC in Chinese populations. In our previous study, the presence of <it>Helicobacter pylori </it>(<it>H. pylori</it>) was found to play a protective role in development of ESCC. The interaction of COX-2 and <it>H. pylori </it>in gastric cancer was well investigated. However, literature on their interaction in ESCC risk is scarce. The purpose of this study was to evaluate the association and interaction between COX-2 single nucleotide polymorphism (SNP), <it>H. pylori </it>infection and the risk of developing ESCC.</p> <p>Methods</p> <p>One hundred and eighty patients with ESCC and 194 controls were enrolled in this study. Personal data regarding related risk factors, including alcohol consumption, smoking habits and betel quid chewing, were collected via questionnaire. Genotypes of the COX-2 -1195 polymorphism were determined by PCR-based restriction fragment length polymorphism. <it>H. pylori </it>seropositivity was defined by immunochromatographic screening test. Data was analyzed by chi-squared tests and polytomous logistics regression.</p> <p>Results</p> <p>In analysis adjusting for the covariates and confounders, <it>H. pylori </it>seropositivity was found to be inversely association with the ESCC development (adjusted OR: 0.5, 95% CI: 0.3 – 0.9). COX-2 -1195 AA homozygous was associated with an increased risk of contracting ESCC in comparison with the non-AA group, especially among patients with <it>H. pylori </it>seronegative (adjusted OR ratio: 2.9, 95% CI: 1.2 – 7.3). The effect was strengthened among patients with lower third ESCC (adjusted OR ratio: 6.9, 95% CI 2.1 – 22.5). Besides, <it>H. pylori </it>seropositivity conveyed a notably inverse effect among patients with COX-2 AA polymorphism (AOR ratio: 0.3, 95% CI: 0.1 – 0.9), and the effect was observed to be enhanced for the lower third ESCC patients (AOR ratio: 0.09, 95% CI: 0.02 – 0.47, <it>p </it>for multiplicative interaction 0.008)</p> <p>Conclusion</p> <p><it>H. pylori </it>seropositivity is inversely associated with the risk of ESCC in Taiwan, and COX-2 -1195 polymorphism plays a role in modifying the influence between <it>H. pylori </it>and ESCC, especially in lower third esophagus.</p
Efficacy of insect larval meal to replace fish meal in juvenile barramundi, Lates calcarifer reared in freshwater
The present experiment was conducted to evaluate the efficacy of dietary protein from black soldier fly, Hermetia illucens, larval meal (BSFL) to replace fish meal (FM) protein in juvenile barramundi, Lates calcarifer. Larvae of black soldier fly were fed with the underutilised crop, sesbania, Sesbania grandiflora. Five isonitrogenous (44% crude protein) and isocaloric (16.0 kJ available energy/g) experimental diets were formulated to replace FM using processed BSFL meal at 0 (control), 25% (BSFL25), 50% (BSFL50), 75% (BSFL75) and 100% (BSFL100). Data for proximate and amino acid analysis suggested BSFL meal as an inferior protein ingredient than FM, but parallel to soybean meal. At the end of 8 weeks of fish feeding trial, there were no significant differences in the average weight gain (WG) and specific growth rate among the group of fish-fed control, BSFL25 and BSFL50 diets (P < 0.05). Although numerical differences were recorded in the fish whole-body proximate composition, crude protein and moisture content were not much affected by the different dietary treatments. Essential amino acids including arginine, histidine, lysine and methionine were found to be higher in the whole body of fish-fed BSFL100 diet. Broken line regression analysis of average WG showed an optimum FM replacement level of 28.4% with BSFL meal. Therefore, the present experiment clearly demonstrates that the maximal dietary inclusion level of BSFL meal as FM protein replacer for the optimum growth of juvenile barramundi reared in freshwater could be greater than 28.4% but less than 50%, without any adverse effects on the fish whole-body proximate and amino acid composition
Obesity, clinical, and genetic predictors for glycemic progression in Chinese patients with type 2 diabetes:A cohort study using the Hong Kong Diabetes Register and Hong Kong Diabetes Biobank
The Origin of Minus-end Directionality and Mechanochemistry of Ncd Motors
Adaptation of molecular structure to the ligand chemistry and interaction with the cytoskeletal filament are key to understanding the mechanochemistry of molecular motors. Despite the striking structural similarity with kinesin-1, which moves towards plus-end, Ncd motors exhibit minus-end directionality on microtubules (MTs). Here, by employing a structure-based model of protein folding, we show that a simple repositioning of the neck-helix makes the dynamics of Ncd non-processive and minus-end directed as opposed to kinesin-1. Our computational model shows that Ncd in solution can have both symmetric and asymmetric conformations with disparate ADP binding affinity, also revealing that there is a strong correlation between distortion of motor head and decrease in ADP binding affinity in the asymmetric state. The nucleotide (NT) free-ADP (?-ADP) state bound to MTs favors the symmetric conformation whose coiled-coil stalk points to the plus-end. Upon ATP binding, an enhanced flexibility near the head-neck junction region, which we have identified as the important structural element for directional motility, leads to reorienting the coiled-coil stalk towards the minus-end by stabilizing the asymmetric conformation. The minus-end directionality of the Ncd motor is a remarkable example that demonstrates how motor proteins in the kinesin superfamily diversify their functions by simply rearranging the structural elements peripheral to the catalytic motor head domain
The Hubbard model within the equations of motion approach
The Hubbard model has a special role in Condensed Matter Theory as it is
considered as the simplest Hamiltonian model one can write in order to describe
anomalous physical properties of some class of real materials. Unfortunately,
this model is not exactly solved except for some limits and therefore one
should resort to analytical methods, like the Equations of Motion Approach, or
to numerical techniques in order to attain a description of its relevant
features in the whole range of physical parameters (interaction, filling and
temperature). In this manuscript, the Composite Operator Method, which exploits
the above mentioned analytical technique, is presented and systematically
applied in order to get information about the behavior of all relevant
properties of the model (local, thermodynamic, single- and two- particle ones)
in comparison with many other analytical techniques, the above cited known
limits and numerical simulations. Within this approach, the Hubbard model is
shown to be also capable to describe some anomalous behaviors of the cuprate
superconductors.Comment: 232 pages, more than 300 figures, more than 500 reference
Aberrant Expression of Oncogenic and Tumor-Suppressive MicroRNAs in Cervical Cancer Is Required for Cancer Cell Growth
MicroRNAs (miRNAs) play important roles in cancer development. By cloning and sequencing of a HPV16+ CaSki cell small RNA library, we isolated 174 miRNAs (including the novel miR-193c) which could be grouped into 46 different miRNA species, with miR-21, miR-24, miR-27a, and miR-205 being most abundant. We chose for further study 10 miRNAs according to their cloning frequency and associated their levels in 10 cervical cancer- or cervical intraepithelial neoplasia-derived cell lines. No correlation was observed between their expression with the presence or absence of an integrated or episomal HPV genome. All cell lines examined contained no detectable miR-143 and miR-145. HPV-infected cell lines expressed a different set of miRNAs when grown in organotypic raft cultured as compared to monolayer cell culture, including expression of miR-143 and miR-145. This suggests a correlation between miRNA expression and tissue differentiation. Using miRNA array analyses for age-matched normal cervix and cervical cancer tissues, in combination with northern blot verification, we identified significantly deregulated miRNAs in cervical cancer tissues, with miR-126, miR-143, and miR-145 downregulation and miR-15b, miR-16, miR-146a, and miR-155 upregulation. Functional studies showed that both miR-143 and miR-145 are suppressive to cell growth. When introduced into cell lines, miR-146a was found to promote cell proliferation. Collectively, our data indicate that downregulation of miR-143 and miR-145 and upregulation of miR-146a play a role in cervical carcinogenesis
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