Effects of PCNL under the guidance of hologram technology on stress response and renal injury factors in patients with complex kidney stones.

Background: To investigate the effect of percutaneous nephrolithotomy (PCNL) guided by holographic image technology on stress response and renal injury factors in patients with complex renal calculi. Methods: A retrospective analysis was conducted on the clinical data of 70 patients admitted to our hospital between August 2022 and June 2023 who had complex kidney stones. The patients were divided into two groups, namely, group A and group B, based on whether they received guidance from preoperative holographic imaging technology. Group A consisted of forty patients who underwent PCNL after undergoing renal CT examination prior to surgery, while Group B included thirty patients who underwent PCNL guided by holographic imaging technology. Various indexes, including operative factors, stress response, inflammatory response, renal injury factors, renal function, complication rate, and the rate of achieving complete stone clearance in a single procedure, were compared between the two groups. Results: In group B, the puncture time and operation time of the target calyces were shorter compared to group A, additionally, the intraoperative blood loss in group B was lower than that in group A (P<0.05). 24 h after surgery, group B exhibited higher levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) compared to group A, additionally, the level of malondialdehyde (MDA) in group B was lower than that in group A (P<0.05). 24 h after surgery, group B exhibited lower levels of tumor necrosis factor a (TNF-a), interleukin-6 (IL-6), IL-1, and hypersensitive C-reactive protein (hs-CRP) compared to group A (P<0.05). Furthermore, group B showed lower levels of neutrophil gelatinase-associated lipid carrier protein (NGAL), inducible protein-8-like molecule 2 (TIPE2), and b2-microglobulin (b2-MG) than group A at the 7-day mark (P<0.05). 24 h after the operation, There was no statistically significant difference observed in the levels of SCr, BUN, between group A and group B group (P > 0.05); however, exhibited lower levels of CysC compared to group A (P < 0.05). Additionally, there were no significant differences in postoperative complications between group B and group A (P>0.05). Furthermore, one month after surgery, the one-time stone clearance rate in group B was significantly higher than that in group A (P<0.05). Conclusions: PCNL under the guidance of hologram technology can shorten the time of puncture target calyce and operation, reduce the amount of intraoperative blood loss, effectively reduce the postoperative stress reaction and inflammatory reaction of patients, reduce the level of renal injury factors, improve renal function, and increase the one-time stone clearance rate.

Size matters: Altering antigen specific immune tolerance by tuning size of particles.

Precisely co-delivering antigens and immunosuppressants via nano/microcarriers to antigen-presenting cells (APCs) to induce antigen-specific immune tolerance represents a highly promising strategy for treating or preventing autoimmune diseases. The physicochemical properties of nano/microcarriers play a pivotal role in regulating immune function, with particle size and surface charge emerging as crucial parameters. In particular, very few studies have investigated micron-scale carriers of antigens. Herein, various nanoparticles and microparticles (NPs/MPs) with diverse particle sizes (ranging from 200 nm to 5 µm) and surface charges were prepared. Antigen peptides (MOG35-55) and immunosuppressants were encapsulated in these particles to induce antigen-specific immune tolerance. Two emulsifiers, PVA and PEMA, were employed to confer different surface charges to the NPs/MPs. The in vitro and in vivo studies demonstrated that NP/MP-PEMA could induce immune tolerance earlier than NP/MP-PVA and that NP/MP-PVA could induce immune tolerance more slowly and sustainably, indicating that highly negatively charged particles can induce immune tolerance more rapidly. Among the different sizes and charged particles tested, 200-nm-NP-PVA and 3-µm-MP-PEMA induced the greatest immune tolerance. In addition, the combination of NPs with MPs can further improve the induction of immune tolerance. In particular, combining 200 nm-NP-PVA with 3 µm-MP-PEMA or combining 500 nm-NP-PEMA with 3 µm-MP-PVA had optimal therapeutic efficacy. This study offers a new perspective for treating diseases by combining NPs with MPs and applying different emulsifiers to prepare NPs and MPs.

Intervention strategies for management of comorbid depression among individuals with hypertension: a scoping review protocol.

INTRODUCTION: Hypertension and depression often coexisted, leading to poor health outcome and significant challenges in healthcare management. Since no guidelines or consensus are available for health professionals to manage this comorbidity, identifying interventions in current literature is crucial for gaining a clear picture of evidence and informing future research directions and clinical practice. This scoping review is designed to address this gap by systematically mapping the range of potential interventions for managing comorbid hypertension and depression. METHODS AND ANALYSIS: Following the Joanna Briggs Institute guidelines for scoping review, this review will comprehensively search databases including PUBMED, Embase, PsycINFO, CINAHL, Cochrane Library Databases, Chinese Biomedical Literature Database and Chinese National Knowledge Infrastructure. Grey literature will be sourced from Google Scholar. A year limit of January 2004-December 2023 will be applied to retrieve the most current peer-reviewed articles in English and Chinese language only. Two reviewers will individually screen and the process will be documented in Preferred Reporting Items for Systematic Reviews and Meta-Analyses for scoping reviews. This review will explore a range of non-pharmacological and multicomponent interventions including psychosocial support, educational programmes, telemedicine and integrated healthcare models. Data extraction will follow the Template for Intervention Description and Replication checklist to ensure detailed and standardised reporting of intervention components. The synthesis of findings will employ both quantitative and qualitative methods to provide a comprehensive overview of the intervention landscape. ETHICS AND DISSEMINATION: This scoping review, which involves secondary data analysis of publicly available sources, does not require ethical approval. Findings will be disseminated through peer-reviewed publications and presentations at relevant conferences. STUDY REGISTRATION: Open Science Framework registry (osf.io/j7gt8) in Centre for Open Science on 29 January 2024.

Communication behavior recognition using CNN-based signal analysis.

This article explores the technology of recognizing non-cooperative communication behavior, with a specific emphasis on analyzing communication station signals. Conventional techniques for analyzing signal data frames to determine their identity, while precise, do not have the ability to operate in real-time. In order to tackle this issue, we developed a pragmatic architecture for recognizing communication behavior and a system based on polling. The method utilizes a one-dimensional convolutional neural network (CNN) to segment data, hence improving its ability to recognize various communication activities. The study assesses the reliability of CNN in several real-world scenarios, examining its accuracy in the presence of noise interference, varying lengths of interception signals, interferences at different frequency points, and dynamic changes in outpost locations. The experimental results confirm the efficacy and dependability of the convolutional neural network in recognizing communication behavior in various contexts.

Large-scale Prospective Validation Study of a Multiplex RNA Urine Test for Noninvasive Detection of Upper Tract Urothelial Carcinoma.

BACKGROUND: Current approaches for diagnosis and monitoring of upper tract urothelial carcinoma (UTUC) are often invasive, costly, and not efficient for early-stage and low-grade tumors. OBJECTIVE: To validate a noninvasive urine-based RNA test for accurate UTUC diagnosis. DESIGN, SETTING, AND PARTICIPANTS: Urine samples were prospectively collected from 61 patients with UTUC and 99 controls without urothelial carcinomas, in five clinical centers between October 2022 and August 2023 prior to any invasive test (cystoscope or ureteroscope) or treatment. All samples were analyzed with a urine-based RNA test composed of eight genes (CA9, CCL18, ERBB2, IGF2, MMP12, PPP1R14D, SGK2, and SWINGN). The test results were presented with a risk score for each participant, which was applied to categorize patients into low- or high-risk groups. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The diagnosis of UTUC was based mainly on preoperative radiological examination criteria and confirmed by postoperative pathological results. The recursive feature elimination and support vector machine algorithms, χ2, and Student t test were used. RESULTS AND LIMITATIONS: The eight-gene urine test accurately detected UTUC patients and controls with an area under the curve (AUC) of 0.901 in a single-center testing cohort (n = 93) and an AUC of 0.926 in a multicenter clinical validation cohort (n = 66). In the merged validation cohort, the eight-gene urine test achieved high sensitivity of 90.16%, specificity of 88.89%, and overall accuracy of 89.38%. Remarkably, excellent performance was achieved in 11 low-grade UTUC patients with accuracy of 100%. However, this study collected the urine of UTUC patients only at a single preoperative time point and did not perform continuous tests during the pathological process of UTUC in the surveillance population. CONCLUSIONS: Our results demonstrated that the eight-gene urine test can differentiate accurately between UTUC and other urological diseases with high sensitivity and specificity. In clinical practice, it may be used for identifying UTUC patients effectively, leading to reduced reliance on ureteroscopy and blind surgery. PATIENT SUMMARY: In this study, we investigated a multiplex RNA urine test for noninvasive upper tract urothelial carcinoma (UTUC) diagnosis before treatment. We found that the risk scores derived from the multiplex RNA urine test differed significantly between UTUC patients and corresponding controls.

Regio- and Enantioselective Construction of Tetrazole Hemiaminal Esters and Related Prodrugs via Biocatalytic Dynamic Kinetic Resolution.

Enzyme-catalyzed dynamic kinetic resolution was applied to the one-pot regio- and enantioselective synthesis of 2,5-disubstituted tetrazole hemiaminal esters, among which 72% of the products were obtained in excellent enantiopurities (99% ees). Tunable stereoselectivity was achieved by using different types of enzymes during the synthesis of a key intermediate for a clinic drug candidate. Successful preparation of tetrazole ester prodrugs and high catalyst recyclability further demonstrated the potential practical application of this protocol.

Southern Hemisphere dominates recent decline in global water availability.

Global land water underpins livelihoods, socioeconomic development, and ecosystems. It remains unclear how water availability has changed in recent decades. Using an ensemble of observations, we quantified global land water availability over the past two decades. We show that the Southern Hemisphere has dominated the declining trend in global water availability from 2001 to 2020. The significant decrease occurs mainly in South America, southwestern Africa, and northwestern Australia. In the Northern Hemisphere, the complex regional increasing and decreasing trends cancel each other, resulting in a negligible hemispheric trend. The variability and trend in water availability in the Southern Hemisphere are largely driven by precipitation associated with climate modes, particularly the El Niño-Southern Oscillation. This study highlights their dominant role in controlling global water availability.

Evaluation of cross-immunity among major porcine circovirus type 2 genotypes by infection with PCV2b and PCV2d circulating strains.

There are three main genotypes of porcine circovirus type 2 (PCV2), namely PCV2a, PCV2b and PCV2d, of which PCV2b and PCV2d are currently the most common. There are antigenic differences between these different genotypes. To explore the effect of PCV2 antigen differences on the immune protection provided by vaccines, a cross-immune protection test was carried out in pigs. Three genotype strains, PCV2a-CL, PCV2b-MDJ and PCV2d-LNHC, were inactivated and emulsified to prepare inactivated vaccines to immunize pigs, who were then challenged with the circulating strains PCV2b-BY and PCV2d-LNHC. Immunoperoxidase monolayer assays (IPMAs) and micro-neutralization assays were used to detect antibodies against the three different genotypes of PCV2. The results showed that the three genotype vaccines induced pigs to produce antibodies against the same and different genotypes of PCV2, but the levels of IPMA and neutralizing antibodies against the same genotype were higher than those against different genotypes. Quantitative Polymerase Chain Reaction (qPCR), virus titration and immunohistochemistry were used to detect PCV2 genomic DNA, live virus and antigen, respectively, in inguinal lymph nodes of experimental pigs. Following challenge with the PCV2b-BY strain, the viral DNA load in the inguinal lymph nodes of pigs immunized with the three genotype vaccines was reduced by more than 99 % compared to the unimmunized group. Following challenge with the PCV2d-LNHC strain, the viral DNA loads in the inguinal lymph nodes of pigs immunized with PCV2a, PCV2b and PCV2d genotype vaccines were reduced by 93.8 %, 99.8 % and 98.3 %, respectively, compared to unimmunized controls. In addition, neither live PCV2 virus nor antigen were detected in the inguinal lymph nodes of pigs immunized with any of the genotype vaccines (0/18), but both were detected in the lymph nodes of experimental pigs in the unimmunized control group (6/6). These findings suggest that, although the antigenic differences of the three genotype strains induce significant differences in antibody levels, they seem to have little effect on cross-protection between different genotypes.

Impact of porcine circovirus type 2 on porcine epidemic diarrhea virus replication in the IPI-FX cell line depends on the order of infection.

Introduction: A study in 2006 showed that the clinical course of PEDV disease was markedly aggravated by transplacental infection of PCV2. Therefore, we investigated whether the small intestine supports PCV2 replication and the effect of PCV2 infection on PEDV replication in epithelial cells in vitro. Methods: To confirm the intestinal tropism of PCV2, the viral loads in the small-intestinal tissues after PCV2 infection were determined with virus titration, and the viral titers in the infected pig jejunum, ileum, ileocecal valve, and colon were 104.86, 104.09, 102.52, and 102.35 TCID50/g, respectively. We then determined the propagation characteristics of PCV2 in ileal epithelial cells (IPI-FX) and jejunal epithelial cells (IPEC-J2) with an immunoperoxidase monolayer assay, virus titration, and an immunofluorescence assay. Both IPI-FX and IPEC-J2 cells supported the replication of PCV2, with titers of 105.5 and 105.0 TCID50/ml, respectively. We established an infection model of PCV2 and PEDV in IPI-FX cells and found that PEDV and PCV2 infected the cells individually and together. The effects of PCV2 infection on PEDV replication were determined with reverse transcription-quantitative PCR (qPCR), western blotting, and virus titration. When PCV2 infected IPI-FX cells before PEDV, PCV2 significantly inhibited the replication of PEDV in a dose- and time-dependent manner and that the mRNAs of IFN-ß, TNF-α, IL1ß, and OASL were downregulated (detected with qPCR). Surprisingly, when IPI-FX cells were co-infected with PCV2 and PEDV, PCV2 promoted the replication of PEDV, the expression of the host IFN-ß, TNF-α, IL1ß, and OASL mRNAs was upregulated. Discussion: These findings demonstrate that the co-infection of IPI-FX cells with PCV2 and PEDV represents an excellent in vitro model in which to investigate their combined pathogenic mechanisms.

Enzyme-Catalyzed Dynamic Kinetic Resolution of 2-Formylbenzoic Acids for the Asymmetric Synthesis of Phthalidyl Esters and Related Prodrugs.

An enzyme-catalyzed dynamic kinetic resolution strategy was applied for the asymmetric synthesis of phthalidyl esters in high yields (up to 95%) and enantiomeric purities (up to 99% ee) through a direct one-pot procedure. Preparation of phthalidyl ester prodrugs and a scale-up reaction demonstrated the potential of this method for practical applications.

The relationship between round window and ear canal Cochlear microphonic.

Hypothesis: Cochlear microphonic recorded at ear canal (CM-EC) can be a substitute for the one recorded at round window (CM-RW). Background: Almost all clinics do not measure tone-burst evoked CM due to technical difficulty although it can provide more information than click evoked CM. Moreover, clinicians like the CM-EC more than that measured at CM-RW because CM-EC is non-invasive. There is difference between CM-RW and CM-EC, for example, CM-EC is less prominent than CM-RW, therefore, studying tone-burst evoked CM-EC and its relationship with CM-RW are highly significant and can promote the clinical application of CM-EC. Method: Nine guinea pigs were randomly allocated into three groups, group 1 was not exposed to noise, called normal control. group 2 and group 3 were exposed to the low- (0.5-2 kHz) and high-frequency band-noise (6-8 kHz) at 120 dB SPL for 1 h, respectively. It was difficulty to record low-frequency CM due to severe environmental interruption, in current study the recording technology of tone-burst evoked CM was optimized so that tone-burst evoked CM was measured across full speech frequency (0.5-8 kHz) in the presence of normal hearing and noise induced hearing loss (NIHL). Results: CM-RW and CM-EC were successfully recorded across speech frequency. Significant reduction in CM amplitude was observed at 0.5 and 2 kHz in group 2, at 6 and 8 kHz in group 3 as compared to group 1, p < .05, indicating that CM amplitude was sensitive to band-noise exposure. Significant correlation between CM-RW and CM-EC was also verified, p < .05. Conclusion: CM-EC is a useful objective test for evaluation of hearing function; the result of current study supports the clinical application of non-invasive CM-EC.

Optimizing the Measurement of 0.5-kHz Cubic Distortion Product Otoacoustic Emission.

BACKGROUND: The measurement of low-frequency cubic distortion product otoacoustic emission, for example, 0.5-kHz cubic distortion product otoacoustic emission, is often severely affected by background noise, and currently 0.5-kHz cubic distortion product otoacoustic emission is not commonly applicable in clinical setting. METHODS: The fundamental part of current study was the optimization of recording technology to reduce noise interference with the measurement of 0.5-kHz cubic distortion product otoacoustic emission and to establish the response patterns of cubic distortion product otoacoustic emission across speech frequencies from 0.5 to 8kHz in the presence of normal hearing and noise-induced hearing loss. RESULTS: After a series of optimization, a clinically applicable technology of measuring 0.5-kHz cubic distortion product otoacoustic emission was successfully completed via animal model. Cubic distortion product otoacoustic emission was recorded in 6 guinea pigs across speech frequencies from 0.5 to 8kHz before and after exposure to white bandnoise between 0.5 and 2 kHz. After noise exposure, significant reduction in the signal-to-noise ratio of cubic distortion product otoacoustic emission was found at 0.5 and 2 kHz, indicating our recording technology was sensitive and accurate. Other interesting finding was the reduction in cubic distortion product otoacoustic emiss ion-s ignal -to-n oise ratio at 4 and 6 kHz although the reduction was not statistically significant probably because of short exposure time. The result implied that the damaging effect induced by low-frequency noise exposure might spread upward to high-frequency region. CONCLUSIONS: Our recording technology was stable and reliable and had the great potentiality to be used in clinical setting.

Fragment-Based Dynamic Combinatorial Chemistry for Identification of Selective α-Glucosidase Inhibitors.

Efforts to combine advantages of fragment-based drug design (FBDD) and dynamic combinatorial chemistry (DCC) for the development of selective α-glucosidase inhibitors were described. Starting from 5 rationally designed fragments, two iterative dynamic combinatorial libraries (DCLs) comprising 29 acylhydrazone products were generated and screened using α-glucosidase and α-amylase as the templates. The optimal ligand identified showed substantial α-glucosidase inhibition with high selectivity over α-amylase as well as low cytotoxicity. Furthermore, inhibition type and detailed ligand/enzyme binding interactions were elucidated by the binding kinetic study and docking simulation, respectively.

Development of a performance measurement system for general practitioners' office in China's primary healthcare.

BACKGROUND: General practitioners are the main providers of primary care services. To better strengthen the important role of general practitioners in primary healthcare services, China is promoting the general practitioners' office system. There is a lack of well-accepted methods to measure the performance of general practitioner offices in China. We thus aim to develop a systematic and operable performance measurement system for evaluating the general practitioner's office. METHODS: We establish an index pool of the performance measurement system of general practitioners' offices by a cross-sectional study and the literature research method and adopt the focus group method to establish the preliminary system. The Delphi method is then used to conduct three rounds of consultation to modify indices, which aims to form the final indicator system. We determine the weight of each index by the analytic hierarchy process method, which together with the final indicator system constitutes the final performance measurement system. Finally, we select three offices from three different cities in Sichuan Province, China, as case offices to conduct the case study, aiming to assess its credibility. RESULTS: Our results show that the first office scored 958.5 points, the second scored 768.1 points, and the third scored 947.7 points, which corresponds to the reality of these three offices, meaning that the performance measurement system is effective and manoeuvrable. CONCLUSIONS: Our study provides support for standardizing the functions of China's general practitioner's office, improving the health service quality of generalists, and providing a theoretical basis for the standardization of the general practitioner's office.

Rapid detection of porcine circovirus type 2 by a red latex microsphere immunochromatographic strip.

To establish a rapid and specific antigen detection method for porcine circovirus type 2 (PCV2), monoclonal antibodies (mAbs) were produced against the PCV2 epidemic strains and a red latex microsphere immunochromatographic strip was established. A total of eight anti-PCV2b and four anti-PCV2d mAbs were produced, and seven mAbs were confirmed to react with PCV2a, PCV2b, and PCV2d strains using an immunoperoxidase monolayer assay. The results of micro-neutralization tests showed that the mAbs 2C8, 9H4, 10G7, 7B9, and 7C7 had good neutralizing activity, whereas the neutralizing activity of the mAbs 4B3, 4C9, 6H9, and 7E2 was lower than 50%. Three mAbs, 4B3, 7C7, and 9H4, and PCV2 pAb were selected for the establishment of a red latex microsphere immunochromatographic strip, and the combination of mAb 7C7 labeled with red latex microspheres and mAb 9H4 exhibited the greatest detection ability. The immunochromatographic strip had minimum detection limits of 102.5 TCID50/0.1 ml, 100.7 TCID50/0.1 ml, and 101.5 TCID50/0.1 ml for PCV2a/CL, PCV2b/MDJ, and PCV2d/LNHC, respectively. Furthermore, no cross-reactivity was found for African swine fever virus, classical swine fever virus, porcine respiratory and reproductive syndrome virus, porcine parvovirus, porcine pseudorabies virus, porcine circovirus type 1, transmissible gastroenteritis virus, porcine epidemic diarrhea virus, porcine rotavirus, or porcine deltacoronavirus using the immunochromatographic strip. Using PCR as a reference standard, the detection sensitivity, specificity, and overall coincidence rate of the immunochromatographic strip were 81.13%, 100%, and 90.00%. Additionally, the detection ability of the immunochromatographic strip was correlated with that of virus titration. The immunochromatographic strip was used to detect 183 clinical disease samples, and the average positive detection rate was 22.95%. In summary, this method has good sensitivity and specificity and is simple, convenient, and quick to operate. It has high application value for on-site diagnosis of PCV2 and virus quantification. KEY POINTS: • A red latex microsphere immunochromatographic strip for PCV2 detection was developed. • The method was not only simple to operate, but also takes less time. • The method had good sensitivity and specificity.

Development of Urease Inhibitors by Fragment-Based Dynamic Combinatorial Chemistry.

In this study, fragment-based dynamic combinatorial chemistry (DCC) was explored for the development of novel urease inhibitors. Based on a rationally designed fragment, two iteratively evolved dynamic combinatorial libraries (DCLs) were generated and screened in the presence of urease template. The best ligand identified revealed not only strong urease inhibition but also low cytotoxicity. Additionally, a possible inhibitory mechanism was elucidated in the binding kinetics study and docking simulation.

Specific inhibition of the interaction between pseudorabies virus DNA polymerase subunits UL30 and UL42 by a synthetic peptide.

Pseudorabies virus (PRV) is a ubiquitous and economically important swine alphaherpesvirus that causes devastating swine diseases worldwide. PRV-encoded DNA-dependent DNA polymerase, comprised of the catalytic subunit UL30 and the accessory subunit UL42, is essential for viral replication. PRV UL30 and UL42 act as a heterodimer with UL30 harboring inherent DNA polymerase activity and UL42 conferring processivity on the DNA polymerase holoenzyme. The formation of PRV UL30/UL42 heterodimer holoenzyme through protein-protein interactions is indispensable for viral replication. In work described here, we defined the key domains that mediate PRV UL30/UL42 interaction, and found that the 41 carboxy-terminal amino acids region of PRV UL30 is critical for its interaction with UL42. Intriguingly, a synthetic peptide corresponding to these 41 carboxy-terminal amino acid residues efficiently disrupted PRV UL30/UL42 interaction through competitively binding to UL42. These findings suggest that the peptides from the PRV DNA polymerase UL30/UL42 subunit interface may represent potential targets for designing a novel intervention strategy against PRV infection. This work further strengthens the concept that the herpesvirus DNA polymerase catalytic subunits utilize their extreme carboxy-terminal domains as a conserved mechanism to associate with their cognate accessory subunits, providing us the opportunity of designing novel antiviral agents against herpesvirus infection through disruption of the herpesvirus DNA polymerase subunit interactions.

Extensive hearing loss induced by low-frequency noise exposure.

Background: With little attention given to low-frequency traffic noise and our understanding that cochlear function may be highly susceptible to low-frequency noise, there is an urgent need to determine traffic noise-induced hearing loss (NIHL), not only the hearing loss at low frequency but also the possible high-frequency hearing loss. Methods: The current study aims to investigate the potential for extensive hearing loss induced by exposure to 0.063 kHz octave band noise (OBN), which is an important component of low-frequency traffic noise. The threshold of auditory brainstem response (ABR) was used to evaluate hearing function before and after noise exposure. Chinchillas were randomly assigned into seven different groups. Group 63-3 h/6 h, Group 2 k-3 h/6 h, and group 4 k-3 h/6 h were exposed for either 3 or 6 h to 0.063, 2, and 4 kHz OBN at 90 dB SPL, respectively. The control group was not exposed to noise. Results: Significant ABR threshold-shifts (TS) were observed at 0.88, 2, 4, and 5.7 kHz in Group 63-6 h, and at 2.8 and 4 kHz in Group 2 k-6 h, and at 5.7 kHz in Group 4 k-6 h. ABR-TS were consistent with outer hair cell (OHC) losses, exposure to 0.063 kHz OBN at 90 dB SPL for 6 h induced large-scale losses of OHC both in low- and high-frequency region. Conclusions: Exposure to 0.063 kHz low-frequency OBN at 90 dB SPL for 6 h leads to significant hearing loss over an extensive range from low to high frequencies.

Purification of Porcine Circovirus Type 2 Using an Affinity Chromatography Based on a Neutralizing Monoclonal Antibody against Viral Capsid Protein.

Porcine circovirus type 2 (PCV2) is a DNA virus without an envelope. The viral particle is icosahedral and has a diameter of approximately 17 nm. In order to obtain the purified virus, a broad-spectrum monoclonal antibody 3A5 against PCV2 was coupled to CNBr-activated SepharoseTM 4B, and an affinity chromatography was established for PCV2 purification. A total of 6.5 mg of purified PCV2a/LG with 97% purity was obtained from 120 mL of the viral culture medium, and only PCV2 was detected by electron microscopy. No significant changes in the antigenic characteristics of the purified virus were detected by a capture enzyme-linked immunosorbent assay (ELISA). Furthermore, the titer of the purified PCV2 was 100 times higher than that of the unpurified virus. This affinity chromatography method was also used to purify PCV2b/LN590516 and PCV2d/SD446F16, and the purified viruses were detected by electron microscopy, capture ELISA, and virus titration, respectively. The results showed that these two strains can be successfully purified, but the yield is lower than that of the PCV2a strain. In addition, the purified virus could be used to study the viral adsorption and invasion of PK15 cells using indirect immunofluorescence assays. A large number of PCV2 signals were detected to transfer from the cellular surface to the periphery of the nucleus of the PK15 cells after 30 min of adsorption of the PCV2 to the PK15 cells. The affinity chromatography is a simple and convenient tool to obtain PCV2 with high purity. It could be applied for virus structure analysis, antibody preparation, and viral adsorption and invasion research.