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A high-sensitivity silicon microring (Si MRR) optical biosensor for detecting the nucleocapsid protein of SARS-CoV-2 is proposed and demonstrated. In the proposed biosensor, the surface of a Si MRR waveguide is modified with antibodies, and the target protein is detected by measuring a resonant wavelength shift of the MRR caused by the selective adsorption of the protein to the surface of the waveguide. A Si MRR is fabricated on a silicon-on-insulator substrate using a CMOS-compatible fabrication process. The quality factor of the MRR is approximately 20,000. The resonant wavelength shift of the MRR and the detection limit for the environmental refractive index change are evaluated to be 89 nm/refractive index unit (RIU) and 10−4 RIU, respectively. The sensing characteristics are examined using a polydimethylsiloxane flow channel after the surface of the Si MRR waveguide is modified with the IgG antibodies through the Si-tagged protein. First, the selective detection of the protein by the MRR sensor is experimentally demonstrated by the detection of bovine serum albumin and human serum albumin. Next, various concentrations of nucleocapsid protein solutions are measured by the MRR, in which the waveguide surface is modified with the IgG antibodies through the Si-tagged protein. Although the experimental results are very preliminary, they show that the proposed sensor has a potential nucleocapsid sensitivity in the order of 10 pg/mL, which is comparable to the sensitivity of current antigen tests. The detection time is less than 10 min, which is much shorter than those of other antigen tests. [ABSTRACT FROM AUTHOR]

Objectives: Intermittent administration of parathyroid hormone (PTH) increases systemic bone mass. However, the effect of PTH on osseous and soft tissue healing around implants in osteoporosis patients remains unclear. This study aimed to investigate the effects of PTH on tissue healing around implants in ovariectomized rats and to compare systemic and intraoral administration routes. Material and Methods: Implants were placed at the healed sites of ovariectomized rats 3 weeks after maxillary first molar extraction. Rats were randomly divided into two groups that received either daily systemic subcutaneous or local intraoral PTH administration. Maxillae were dissected to examine bone architectures with micro‐computed tomography images. Histomorphometric and immunohistochemical analyses were performed to evaluate osseous and soft tissue healing around the implants. Results: Regardless of the administration route, PTH significantly increased bone area and the numbers of osteoblasts, osteoclasts, and osteocytes in the first and second inside and outside areas of implant threads, in addition to decreasing the number of sclerostin+ osteocytes. However, the intraoral PTH administration route was superior to the systemic route by significantly improving bone quality and promoting collagen production in the connective tissue around implants. Conclusions: Parathyroid hormone administration promoted both osseous and soft tissue healing around implants, irrespective of administration route. Interestingly, intraoral administration improved the evaluated parameters more than systemic administration. Thus, the intraoral route could become a useful treatment strategy for implant treatment in osteoporosis patients. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the effects of early loads on bone quality and quantity around implants and to compare the effects of early loads on bone quality and quantity with the effects of conventional loads. Materials and Methods: Grade IV‐titanium implants with buttress threads were placed in rat maxillary bone 4 weeks after extraction of first molars. A controlled mechanical load (10 N, 3 Hz, 1800 cycles, 2 days/week) was started via the implants 1 and 3 weeks after implant placement for 2 weeks (early and conventional loads, respectively). Bone quality, defined as distribution of bone cells, types and orientation of collagen fibers, and production of semaphorin3A, its receptor neuropilin‐1, and sclerostin, were quantitatively evaluated. Results: Early loads substantially and positively affected bone quality by changing the preferential alignment of collagen fibers with increased production of type I and III collagens, semaphorin3A, and neuropilin‐1, increased osteoblast numbers, decreased production of sclerostin, and decreased osteoclast numbers both inside and outside the implant threads, when compared with non‐loaded conditions. Conventional loads changed bone quality around implants slightly. Interestingly, early loads had significantly stronger effects on bone quality and quantity based on the evaluation parameters than conventional loads. Conclusions: This is the first report to provide scientific evidence for load initiation time based on both bone quality and quantity around implants. These new findings show that implants with buttress threads transmitted early loads optimally to bone tissue by improving bone quality and quantity inside and outside the implant threads. [ABSTRACT FROM AUTHOR]

Preoperative imaging differentiation between ChRCC and RO is difficult with conventional subjective evaluation, and the development of quantitative analysis is a clinical challenge. Forty-nine patients underwent partial or radical nephrectomy preceded by MRI and followed by pathological diagnosis with ChRCC or RO (ChRCC: n = 41, RO: n = 8). The whole-lesion volume of interest was set on apparent diffusion coefficient (ADC) maps of 1.5T-MRI. The importance of selected texture features (TFs) was evaluated, and diagnostic models were created using random forest (RF) analysis. The Mean Decrease Gini as calculated through RF analysis was the highest for mean_ADC_value. ChRCC had a significantly lower mean_ADC_value than RO (1.26 vs. 1.79 × 10−3 mm2/s, p < 0.0001). Feature selection by the Boruta method identified the first-quartile ADC value and GLZLM_HGZE as important features. ROC curve analysis showed that there was no significant difference in the classification performances between the mean_ADC_value-only model and the Boruta model (AUC: 0.954 vs. 0.969, p = 0.236). The mean ADC value had good predictive ability for the distinction between ChRCC and RO, comparable to that of the combination of TFs optimized for the evaluated cohort. The mean ADC value may be useful in distinguishing between ChRCC and RO. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the time course of lower urinary tract symptoms (LUTS) after artificial urinary sphincter (AUS) implantation based on individual longitudinal changes of patient‐reported outcomes. Methods: This retrospective study included 66 male patients with severe urinary incontinence who were treated with primary AUS implantation between 2009 and 2019. International Consultation on Incontinence Questionnaire‐Short Form (ICIQ‐SF) and International Prostate Symptom Score (IPSS) questionnaires were used to evaluate continence status and LUTS preoperatively, 1, 3, and 12 months after activation, and then annually. The annual changes in scores were calculated with a linear mixed model. Results: Of the 66 patients, 63 (95%) achieved complete or social continence (number of pads used ≤1/d) at 1 month after activation. Mean preoperative ICIQ‐SF, IPSS, and IPSS‐quality of life (QOL) score were 18.9, 14.9, and 5.4, respectively; the corresponding scores at 1 month after activation were 4.5, 9.0, and 1.7 (all P <.001), respectively. During the mean follow‐up period of 36 months, the annual changes in the scores from 1 month after activation were 0.51 (P =.002), −0.30 (P =.184), and 0.19 (P <.001), respectively. As for individual IPSS items, while incomplete emptying, frequency, urgency, and weak stream improved significantly 1 month after activation, no significant changes from 1 month after activation were observed except for longitudinal deterioration of incomplete emptying score (0.08/y, P =.029). Conclusion: Continence status and QOL score markedly improved by AUS implantation immediately, but deteriorated over time. Improved LUTS were maintained without a worsening trend, however. [ABSTRACT FROM AUTHOR]

Dolphins are well known as excellent swimmers for being capable of efficient cruising and sharp acceleration. While studies of the thrust production and power consumption of dolphin swimming have been the main subject for decades, time-varying acceleration process during successive fluke beats still remains poorly understood. In this study, we quantified the time-varying kinematics of a dolphin (Lagenorhynchus obliquidens) by directly recording its burst-accelerating swimming before vertical jump in an aquarium with two synchronized high-speed video cameras. We tracked the three-dimensional trajectories of its beak, body sides, and fluke. We found that dolphin could quickly accelerate from 5.0 m s-1 to 8.7 m s-1 merely by 5 strokes (i.e. 2.5 fluke beats) in 0.7 seconds. During the strokes, it was further found that the dolphin demonstrated a great acceleration in downstroke but less acceleration or even a slight deceleration in upstroke. Hydrodynamic forces and thrust power for each stroke were further estimated based on the equation of body motion and a static hydrodynamic model. The drag coefficient of the dolphin was estimated through computational fluid dynamics (CFD) modeling of the steady flows around a realistic geometric model based on 3-D scan data. The thrust and thrust power were then calculated by combining the body kinematics and the drag coefficient, resulting in a maximum stroke-averaged thrust and power-to-mass ratio of 1.3 × 103 N and 90 W kg-1 at downstroke, and 3.3 × 102 N and 19 W kg-1 at upstroke, respectively. Our results point out the importance of asymmetric kinematics in burst acceleration of dolphin, which may be a useful mechanism for biomimetic design of high-performance underwater robots. [ABSTRACT FROM AUTHOR]

We herein propose a nomenclature for renal calices and anatomical classification of the renal pelvis for endoscopic surgery. We prospectively collected data on a total of 270 patients (540 kidneys) who underwent CT-urography. We then constructed three-dimensional images of the renal pelvis and examined their morphologic classification. Forty-eight kidneys were excluded from this study because of severe hydronephrosis or large renal cysts. The remaining 492 kidneys were included. We systematically categorized each minor calix into five levels: top, upper, middle, lower, and bottom. The upper, middle, and lower calices were typically found in pairs: anterior and posterior. The most common total number of minor calices was eight (51%), followed by seven (30%). We also classified the form of the pelvis into type I: single pelvis (58%) and type II: divided pelvis (42%), according to the branch patterns of the renal pelvis. In type II, the renal pelvis is always bifurcated into the upper branch (top and upper) and lower branch (middle, lower, and bottom). Type I was subclassified into three types: type Ia (43%), the standard type; type Ib (4%), with a wide pelvis; and type Ic (11%), with a narrow pelvis. This anatomical classification can divide the renal pelvis into two major types (subdivided into four types) and name each minor calix. This simple classification enables to share common intrarenal information, thus leading to the development of concrete treatment strategies. [ABSTRACT FROM AUTHOR]

Greater understanding and acceptance of the new concept “bone quality”, which was proposed by the National Institutes of Health and is based on bone cells and collagen fibers, are required. The novel protein Semaphorin3A (Sema3A) is associated with osteoprotection by regulating bone cells. The aims of this study were to investigate the effects of mechanical loads on Sema3A production and bone quality based on bone cells and collagen fibers around implants in rat maxillae. Grade IV-titanium threaded implants were placed at 4 weeks post-extraction in maxillary first molars. Implants received mechanical loads (10 N, 3 Hz for 1800 cycles, 2 days/week) for 5 weeks from 3 weeks post-implant placement to minimize the effects of wound healing processes by implant placement. Bone structures, bone mineral density (BMD), Sema3A production and bone quality based on bone cells and collagen fibers were analyzed using microcomputed tomography, histomorphometry, immunohistomorphometry, polarized light microscopy and birefringence measurement system inside of the first and second thread (designated as thread A and B, respectively), as mechanical stresses are concentrated and differently distributed on the first two threads from the implant neck. Mechanical load significantly increased BMD, but not bone volume around implants. Inside thread B, but not thread A, mechanical load significantly accelerated Sema3A production with increased number of osteoblasts and osteocytes, and enhanced production of both type I and III collagen. Moreover, mechanical load also significantly induced preferential alignment of collagen fibers in the lower flank of thread B. These data demonstrate that mechanical load has different effects on Sema3A production and bone quality based on bone cells and collagen fibers between the inside threads of A and B. Mechanical load-induced Sema3A production may be differentially regulated by the type of bone structure or distinct stress distribution, resulting in control of bone quality around implants in jaw bones. [ABSTRACT FROM AUTHOR]

ABSTRACT Telechelic polymers, macromolecules having two reactive end groups, can serve as building blocks for constructing polymers or polymeric materials that have complex architectures. Among the telechelic polymers, polymers bearing hydroxyl groups at two terminals have been used as components for preparation of functional materials. In the present study, RAFT polymerization of both N-acryloylmorphorin and N-succinimidyl acrylate by using a newly synthesized dithiobenzoate-type chain transfer agent bearing hydroxyl groups at both terminals (HECPHD) was reported. After the acryloylation of the hydroxyl terminals of the obtained polymer, gelation was observed. Furthermore, the polymer could react with a protein via the conjugation of the succinimidyl esters-containing polymers to the amino groups present on the protein surface. The results show that activated esters-bearing polymers with hydroxyl groups at both terminals can be used as building blocks for constructing polymeric materials for an immobilization of biomacromolecules. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1356-1365 [ABSTRACT FROM AUTHOR]