[Mechanism of noise induced hidden hearing loss based on proteomics]

Objective: To explore the mechanism of noise-induced hidden hearing loss by proteomics. Methods: In October 2022, 64 SPF male C57BL/6J mice were divided into control group and noise exposure group with 32 mice in each group according to random sampling method. The noise exposure group was exposed to 100 dB sound pressure level, 2000-16000 Hz broadband noise for 2 h, and the mouse hidden hearing loss model was established. Auditory brainstem response (ABR) was used to test the change of hearing threshold of mice on the 7th day after noise exposure, the damage of basal membrane hair cells was observed by immunofluorescence, and the differentially expressed proteins in the inner ear of mice in each group were identified and analyzed by 4D-Label-free quantitative proteomics, and verified by Western blotting. The results were statistically analyzed by ANOVA and t test. Results: On the 7th day after noise exposure, there was no significant difference in hearing threshold between the control group and the noise exposure group at click and 8000 Hz acoustic stimulation (P>0.05) . The hearing threshold in the noise exposure group was significantly higher than that in the control group under 16000 Hz acoustic stimulation (P<0.05) . Confocal immunofluorescence showed that the basal membrane hair cells of cochlear tissue in noise exposure group were arranged neatly, but the relative expression of C-terminal binding protein 2 antibody of presynaptic membrane in middle gyrus and basal gyrus was significantly lower than that in control group (P<0.05) . GO enrichment analysis showed that the functions of differentially expressed proteins were mainly concentrated in membrane potential regulation, ligand-gated channel activity, and ligand-gated ion channel activity. KEGG pathway enrichment analysis showed that differentially expressed proteins were significantly enriched in phosphatidylinositol 3 kinase-protein kinase B (PI3K-Akt) signaling pathway, NOD-like receptor signaling pathway, calcium signaling pathway, etc. Western blotting showed that the expression of inositol 1, 4, 5-trisphosphate receptor 3 (Itpr3) was increased and the expression of solute carrier family 38 member 2 (Slc38a2) was decreased in the noise exposure group (P<0.05) . Conclusion: Through proteomic analysis, screening and verification of the differential expression proteins Itpr3 and Slc38a2 in the constructed mouse noise-induced hidden hearing loss model, the glutaminergic synaptic related pathways represented by Itpr3 and Slc38a2 may be involved in the occurrence of hidden hearing loss.

[Progress in research of population size estimation by network scale-up method]

Network scale-up method is an indirect population size estimation method based on social network theory. It is widely used in estimating the hidden population size because it does not need to contact the target population. In order to provide reference for the further application of this method, this paper summarizes the traditional network scale-up method, the progress of this method and its combination with new survey techniques.

[Progress on the application of respondent-driven sampling in population size estimation]

Respondent-driven sampling (RDS) is a method of sampling specifically for hidden populations, often applied to transgender women, female sex workers, men who have sex with men, and other groups that are difficult to identify and contact because of stigma and legal constraints. However, this method is gradually applied to the general population. With the continuous improvement of RDS, studies find that the network size of RDS samples can be weighted to estimate the overall situation and population size. This article summarizes the current application progress of RDS in population size estimation and provides ideas for the development of RDS and the use of RDS to carry out relevant research.

[Preliminary observation on the differential expression of metformin in preventing noise-induced hearing loss in inner ear protein group of rats]

Objective: To study the protective effects of metformin on noise-induced hearing loss (NIHL) and its differential protein omics expression profile. Methods: In January 2021, 39 male Wistar rats were randomly divided into control group, noise exposure group and metformin+noise exposure group, with 13 rats in each group. Rats in the noise exposure group and metformin+noise exposure group were continuously exposed to octave noise with sound pressure level of 120 dB (A) and center frequency of 8 kHz for 4 h. Rats in the metformin+noise exposure group were treated with 200 mg/kg/d metformin 3 d before noise exposure for a total of 7 d. Auditory brainstem response (ABR) was used to test the changes of hearing thresholds before noise exposure and 1, 4, 7 d after noise exposure in the right ear of rats in each group. Tandem mass tag (TMT) quantitative proteomics was used to identify and analyze the differentially expressed protein in the inner ear of rats in each group, and it was verified by immunofluorescence staining with frozen sections. Results: The click-ABR thresholds of right ear in the noise exposure group and metformin+noise exposure group were significantly higher than those in the control group 1, 4, 7 d after noise exposure (P<0.05) . The click-ABR threshold of right ear in the metformin+noise exposure group were significantly lower than that in the noise exposure group (P<0.05) . Compared with the noise exposure group, 1035 up-regulated proteins and 1145 down-regulated proteins were differentially expressed in the metformin+noise exposure group. GO enrichment analysis showed that the significantly differentially expressed proteins were mainly involved in binding, molecular function regulation, signal transduction, and other functions. Enrichment analysis of KEGG pathway revealed that the pathways for significant enrichment of differentially expressed proteins included phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway, focal adhesion, diabetic cardiomyopathy, mitogen, and mitogen-activated protein kinase (MAPK) signaling pathway. Immunofluorescence experiments showed that compared with the noise exposure group, the fluorescence intensity of insulin-like growth factor 1 receptor (IGF1R) in the metformin+noise exposure group was increased, and the fluorescence intensity of eukaryotic translation initiation factor 4E binding protein 1 (eIF4EBP1) was decreased. Conclusion: Noise exposure can lead to an increase in rat hearing threshold, and metformin can improve noise-induced hearing threshold abnormalities through multiple pathways and biological processes.

[Application and progress of capture-recapture method in population size estimation]

Capture-recapture method is an economical and straightforward method widely used in fields such as estimating population size and estimating and adjusting incidence or prevalence. This paper reviews the classical capture-recapture method and its improvement and application in population size estimation in referring the subsequent related work.

[Progress on application of spatial epidemiology in HIV/AIDS control and prevention]

Spatial epidemiology focuses on the use of geographic information systems and spatial analysis to study spatial distribution and change tendency of diseases and explore the health status of specific populations. In recent years, spatial epidemiology has been applied in the field of HIV/AIDS prevention and control. This review summarizes the progress in the application of spatial epidemiology in the analysis of spatiotemporal distribution, non-monitoring area data estimation, influencing factors of AIDS and health resource allocation and utilization to provide reference for its application in the prevention and control of AIDS in the future.

[Clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma]

Objective: To analyze the epidemiological, clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma (CCPRCC) based on Chinese patient population. Method: Patients with renal cell carcinoma diagnosed at Peking University First Hospital from June 2016 to June 2020 were included in this study based on the inclusion and exclusion criteria. All cases were grouped according to CCPRCC, clear cell renal cell carcinoma (ccRCC), and papillary renal cell carcinoma (pRCC), and the general clinical, postoperative pathological and follow-up data of the patients were retrospectively analyzed. Result: A total of 18 CCPRCC patients were enrolled in this study, accounting for 0.44% (18/4 110) of the postoperative pathologically confirmed renal cell carcinoma cases in our hospital during this time period. The age range of the included patients was 28-86 years old, with a median age of 49.5 years old. There were 11/18 males and 7/18 females. All CCPRCC patients had no family history of renal malignant tumors. Among them, only one patient with CCPRCC had related clinical symptoms, that was intermittent waist and abdomen pain, while the other 17 cases were found by physical examination without any related symptoms. Compared with ccRCC and pRCC, there was no significant difference in their end stage renal disease history(χ²_ccRCC=0.291, χ²_pRCC=1.161,all P>0.05). The maximum diameter of CCPRCC tumor was smaller than pRCC (χ²=-2.280,P =0.027) but not significantly different from ccRCC (χ²=-0.579,P =0.565). The majority of patients with CCPRCC were in pT1, their pathological stage was earlier than the other two types, and their overall survival was better than ccRCC and pRCC (P<0.05). Conclusion: CCPRCC is a type of renal cell carcinoma with unique epidemiology, clinicopathology and prognostic characteristics. Patients with this subtype have an earlier clinical stage and a better prognosis than ccRCC and pRCC.

Patterns of COVID-19 on computed tomography imaging

PURPOSE

As the designated tertiary referral centre for infectious diseases in Hong Kong, our hospital received the city's first group of patients diagnosed with coronavirus disease 2019 (COVID-19). Herein, we studied the earliest patients admitted to our centre in order to clarify the typical radiological findings, particularly computed tomography (CT) findings, associated with COVID-19.

METHODS

From 22 January 2020 to 29 February 2020, 19 patients with confirmed COVID-19 underwent high-resolution or conventional CT scans of the thorax in our centre. The CT imaging findings of these patients with confirmed COVID-19 in Hong Kong were reviewed in this study.

RESULTS

Ground-glass opacities (GGO) with peripheral subpleural distribution were found in all patients (100%). No specific zonal predominance was observed. All lobes were involved in 16 (84.2%) patients, focal subsegmental consolidations were observed in 14 (73.7%) patients, and interlobular septal thickening was present in 12 (63.2%) patients. No mediastinal lymph node enlargement, centrilobular nodule, or pleural effusion was detected in any of the patients. Other imaging features present in several patients include bronchial dilatation, bronchial wall thickening, and crazy-paving patterns.

CONCLUSIONS

Peripheral subpleural GGO without zonal predominance in the absence of centrilobular nodule, pleural effusion, and lymph node enlargement were consistent findings in patients with confirmed COVID-19. The observed radiological patterns on CT scans can help identify COVID-19 and assess affected patients in the context of the ongoing outbreak.

Transient glacial incision in the Patagonian Andes from ~6 Ma to present

We report a mountain-scale record of erosion rates in the central Patagonian Andes from >10 million years (Ma) ago to present, which covers the transition from a fluvial to alpine glaciated landscape. Apatite (U-Th)/He ages of 72 granitic cobbles from alpine glacial deposits show slow erosion before ~6 Ma ago, followed by a two- to threefold increase in the spatially averaged erosion rate of the source region after the onset of alpine glaciations and a 15-fold increase in the top 25% of the distribution. This transition is followed by a pronounced decrease in erosion rates over the past ~3 Ma. We ascribe the pulse of fast erosion to local deepening and widening of valleys, which are characteristic features of alpine glaciated landscapes. The subsequent decline in local erosion rates may represent a return toward a balance between rock uplift and erosion.

P3129Rheumatic heart diseases screening in Bornean Malaysia: a pilot echocardiography study

Background

Rheumatic heart disease is a major public health issue in developing countries including Malaysia. RHD is a preventable disease. Early detection and appropriate treatment may decrease the disease burden to the society. Rheumatic heart disease screening using portable echocardiography may improve early detection among school children in vulnerable community. This is a pilot study of rheumatic heart disease screening using Vscan among primary school students in the Bornean state of Sabah Malaysia.

Purpose

To evaluate the resources required for RHD screening, prevalence of RHD among school children and awareness among the parents and teachers.

Methods

A cohort of 211 students from a primary school were recruited in 2017–2018. Parental consents were obtained. Seven sessions were conducted at the school. Echocardiography was performed by 2–3 experienced ultrasonographers. Image interpretation as per the 2012 WHF RHD echocardiographic diagnostic criteria.

Results

Of the 211 students, 50% female, age range 7–12 year-old. Ethnic groups include Kadazandusun (87%), Rungus (2.4%), Lundayeh (2%), Chinese (2%). Overall, the average number of student scanned was 4.6 students/device/hour. There was a learning curve observed, whereby initial session only scanned 2 students/device/hour which improved to a maximum of 5.9 students/device/hour. Preliminary findings noted probable RHD among 36% (n=76) of screened subjects. Incidental diagnosis of congenital heart disease among 5 students. The suspected RHD cases were referred for formal echocardiography in the tertiary centre for confirmation. Thus far, 12 students were diagnosed with borderline RHD; the main diagnostic criteria in these cases were at least two morphological features of RHD of the MV without pathological MR or MS. Secondary prophylaxis with antibiotic, dental hygiene and patient education were given.

Conclusion

This is a pilot RHD screening using portable Vscan echocardiography among primary school students in Malaysia. Our study showed it is feasible to conduct RHD screening in the field using portable Vscan. The number of students screened improved with practice. Our preliminary finding suggest RHD is prevalent in this population in Sabah, Malaysia.

Is ultrasonography-guided modified coaxial core biopsy of the breast a better technique?

OBJECTIVE

To compare the diagnostic rate, patient comfort, and complications of ultrasonography-guided breast biopsy using a modified coaxial technique with ultrasonography-guided fine needle aspiration and traditional core biopsy. A secondary objective was to describe the use of the coaxial technique for the biopsy of breast lesions and our initial experience.

DESIGN

Retrospective study.

SETTING

A regional hospital in Hong Kong.

PATIENTS

Patients, who were referred for ultrasonography-guided fine needle aspiration or biopsy from 23 November 2007 to 19 March 2008, were divided into three groups. For breast lesions of 8 mm or smaller, fine needle aspirations were performed. For breast lesions larger than 8 mm, the patients were randomly divided into groups receiving traditional core biopsies and coaxial biopsies. The pathological reports were reviewed.

MAIN OUTCOME MEASURES

Diagnostic rate, patient comfort assessed in terms of pain, and any procedural complications.

RESULTS

A total of 45 ultrasonography-guided fine needle aspirations or biopsies of breast lesions were performed. All core biopsies using the traditional core technique (n=15) and coaxial technique (n=16) were diagnostic. While for fine needle aspirations, three (21%) of 14 were not diagnostic and repeat biopsies were undertaken for the corresponding patients. Except for one breast lesion biopsied with the coaxial technique that revealed invasive ductal carcinoma, all others yielded benign lesions. The average pain score for coaxial biopsies was 2.2, while for traditional core biopsies and fine needle aspirations, average scores were 3.7 and 3.8, respectively (P=0.022). No procedure-related complication was documented with either of the three techniques.

CONCLUSION

Modified coaxial core biopsy of the breast has an optimal diagnostic rate and hence avoids the need for repeat biopsies. It is associated with better patient comfort and no increase in the risk of complications.

Malignant rhabdoid tumour of the oesophagus: a case report

Malignant extrarenal rhabdoid tumour (MERT) of the gastrointestinal tract is rarely reported in the literature. This report describes the clinical and pathological features of a malignant rhabdoid tumour of the oesophagus in a Chinese man. Ivor-Lewis oesophagectomy had been performed. The tumour behaved aggressively and the patient died from disseminated malignancy one year later. This is only the second case report of a malignant rhabdoid tumour affecting the oesophagus.

The C282Y mutation of the HFE gene is not found in Chinese haemochromatotic patients: multicentre retrospective study

OBJECTIVE

To detect two novel mutations (C282Y and H63D) of the HFE gene in Chinese patients with hepatic iron overload.

DESIGN

Multicentre retrospective study.

SETTING

Four public hospitals, Hong Kong.

PARTICIPANTS

Fifty Chinese patients who presented from January 1987 through December 1999 with hepatic iron overload from various causes.

MAIN OUTCOME MEASURES

The DNA from liver biopsy samples was tested for HFE mutations by restriction fragment length polymorphism analysis.

RESULTS

The sample DNA quality was unsatisfactory for analysis of the C282Y mutation in one case and the H63D mutation in nine cases. The C282Y mutation was not detected in any of the 49 satisfactory samples. Three of the 41 samples were heterozygous for the H63D mutation and only one was homozygous, giving an allele frequency of 6.1%. Of the three H63D-heterozygotes, one had beta-thalassaemia major, one had beta-thalassaemia minor, and one had hereditary spherocytosis. None of the 12 patients who were presumed to have primary haemochromatosis were positive for either mutation.

CONCLUSIONS

The classical form of human leukocyte antigen-linked hereditary haemochromatosis appears to be absent form this locality. The H63D mutation is found in a minority (9.8%) of the patients, in whom it may act synergistically with an erythropoietic factor.

Clinical and radiological features of biliary papillomatosis

Biliary papillomatosis is a rare disease with strong potential for malignant degeneration. Diagnosis is often not easy and most are made intraoperatively. In the present study, five patients with biliary papillomatosis admitted between 1990 and 1997 were reviewed. Their clinical presentation, radiological and biochemical findings were analysed. The aim of the study was to discern a set of characteristic features that would enable an early diagnosis. All of the five patients presented with recurrent episodes of acute cholangitis and epigastric pain with raised serum alkaline phosphatase. Imaging modalities including ultrasound, CT, endoscopic retrograde cholangio-pancreatogram, MRI and magnetic resonance cholangio-pancreatogram were reviewed. Salient imaging features included a dilated biliary tree with multiple ill-defined and fuzzy filling defects or endoluminal frond-like mass lesions. In conclusion, biliary papillomatosis is a rare but important cause of biliary obstruction with relapsing cholangitis and obstructive jaundice. With a healthy index of suspicion, the diagnosis can be reached when the above features are available.

Pulmonary arteriovenous malformation. Progressive enlargement with replacement of the entire right middle lobe in a patient with concomitant mitral stenosis

OBJECTIVE

To present a case of pulmonary arteriovenous malformation (AVM) that showed progressive enlargement in a patient with concomitant rheumatic mitral stenosis.

CLINICAL FEATURES

A 73-year-old woman first presented eight years ago because of an uncomplicated acute myocardial infarction. She was noted to have rheumatic mitral stenosis. Six years later, she developed symptomatic sick sinus syndrome for which a permanent pacemaker was implanted. Chest x-ray revealed new development of an opacity in the middle zone of the right lung. Two years later, she was admitted to hospital because of progressive dyspnoea. Chest x-ray showed further increase in size of the right middle zone opacity.

OUTCOME

She died of cardiopulmonary failure on the 18th day in hospital. Autopsy revealed a pulmonary AVM, replacing the entire right middle lobe.

CONCLUSION

The elevated pulmonary vascular resistance caused by mitral stenosis may have increased the preferential flow of blood through the AVM, leading to its rapid enlargement. Patients with concomitant pulmonary AVM and mitral stenosis need to be recognised, as close follow-up and early treatment may be desirable.

Hepatic angiomyolipomas with a deceptive trabecular pattern and HMB-45 reactivity

We report two cases of giant hepatic angiomyolipoma with a prominent component of epithelioid smooth muscle cells exhibiting a distinctive trabecular arrangement. These cells possessed peripherally vacuolated and centrally condensed hyaline cytoplasm. The nuclei were eccentrically placed in the cytoplasm. Immunohistochemically, they expressed HMB-45 intensely in the central condensed cytoplasm and actin in a perimembranous fashion. Staining for desmin, myoglobin and vimentin was negative. HMB-45 may prove to be a sensitive marker for angiomyolipoma with epithelioid cells. Hepatocellular carcinoma and other hepatic tumours with polygonal clear cells can be readily distinguished by these means.

Disseminated Penicillium marneffei infection in HIV-infected subject

Penicillium marneffei is a rare human pathogen predominantly affecting residents of South-east Asia. We report four fatal cases from Hong Kong in human immunodeficiency virus-infected patients. The diagnosis was established by histological examination and confirmed by isolation of the fungus. The infection was disseminated with involvement of lymph nodes, liver, spleen, lung, intestine and bone marrow. The involved organs showed an exclusively anergic tissue reaction characterized by a diffuse infiltrate of fungi-laden macrophages, multiple co-existing opportunistic infections and lymphoid cell depletion. This organism has to be distinguished from Histoplasma capsulatum and Pneumocystis carinii. Establishment of the diagnosis is important not only because this infection is potentially curable, but also it is a likely indicator disease of AIDS in South-east Asia. Penicilliosis marneffei should be suspected in any symptomatic HIV-positive patient who comes from or has visited endemic areas of South-east Asia.

Fine needle aspiration diagnosis of Penicillium marneffei infection

A disseminated infection with Penicillium marneffei, a rare human pathogen that may infect both healthy and immunocompromised patients, was diagnosed by fine needle aspiration cytology in a patient infected with the human immunodeficiency virus. The presence of yeast-form organisms with an eccentric or central dot and occasional septate and elongated forms highly suggested the diagnosis, which was confirmed on culture. Establishment of the diagnosis is important because this infection is potentially curable.

Fine needle aspiration diagnosis of pilomatrixoma. A monomorphic population of basaloid cells with squamous differentiation not to be mistaken for carcinoma

In a case of pilomatrixoma, an initial fine needle aspiration (FNA) biopsy of a skin lesion yielded only a monomorphic population of mitotically active basaloid cells with squamous differentiation, without anucleated ghost cells, chronic inflammatory cells or foreign-body giant cells. These findings suggested a metastatic squamous-cell carcinoma or a malignant tumor of adnexal skin. The correct diagnosis was made by repeat FNA, which yielded the basaloid cells and ghost cells characteristics of pilomatrixoma; the FNA diagnosis was confirmed by subsequent excisional biopsy. This case demonstrates that pilomatrixoma should be considered in the differential diagnosis of skin aspirates that contain a dominant population of basaloid cells. The differentiation of pilomatrixoma from malignant lesions of the head and neck region is discussed.