An integrated framework of mobile crowd estimation for the 2019, July 1st rally in Hong Kong.

Traditional approach of mobile crowd estimation involves counting a group of individuals at a specific place, manually, in real-time. It is a laborious exercise that can be physically and mentally demanding. In Hong Kong, a large rally can last more than six hours, making the manual count method susceptible to human errors. While crowd counting using object detection and tracking has been well-established in computer vision, such application has remained relatively small scale within a controlled indoor setting (e.g. counting people at fixed gateways in a mall). No attempt to date has applied the automatic crowd counting method to count hundreds of thousands of people along an open stretch of rally route within the complex urban outdoor landscape. This research proposed an integrated approach that combines the capture-recapture method in statistics and a Convolutional Neural Network (CNN) method in computer vision to count the mobile crowd. The research teams implemented the integrative approach and counted 276,970 people with a 95% confidence interval of 263,663 to 290,276 in the 2019, July 1st Rally in Hong Kong. This work counted the attendance of a large-scale rally as a proof of concept to fill in a gap in the empirical studies. The intellectual merits and research findings shed useful insights to improve mobile population estimation and leverage alternative data sources to support related scientific applications.

Differentiation of patient-specific void urine-derived human induced pluripotent stem cells to fibroblasts and skeletal muscle myocytes.

Cell-based therapy is a major focus for treatment of stress urinary incontinence (SUI). However, derivation of primary cells requires tissue biopsies, which often have adverse effects on patients. A recent study used human induced pluripotent stem cells (iPSC)-derived smooth muscle myocytes for urethral sphincter regeneration in rats. Here, we establish a workflow using iPSC-derived fibroblasts and skeletal myocytes for urethral tissue regeneration: (1) Cells from voided urine of women were reprogrammed into iPSC. (2) The iPSC line U1 and hESC line H9 (control) were differentiated into fibroblasts expressing FSP1, TE7, vinculin, vimentin, αSMA, fibronectin and paxillin. (3) Myogenic differentiation of U1 and H9 was induced by small molecule CHIR99021 and confirmed by protein expression of myogenic factors PAX7, MYOD, MYOG, and MF20. Striated muscle cells enriched by FACS expressed NCAM1, TITIN, DESMIN, TNNT3. (4) Human iPSC-derived fibroblasts and myocytes were engrafted into the periurethral region of RNU rats. Injected cells were labelled with ferric nanoparticles and traced by Prussian Blue stain, human-specific nuclear protein KU80, and human anti-mitochondria antibody. This workflow allows the scalable derivation, culture, and in vivo tracing of patient-specific fibroblasts and myocytes, which can be assessed in rat SUI models to regenerate urethral damages and restore continence.

Different types of visual cells in the photoreceptor layer of the retinae of the treeshrew (Tupaia belangeri chinensis) as revealed by scanning microscopy.

BACKGROUND: The retinae of treeshrew have never been evaluated by scanning electron microscopic studies. MATERIALS AND METHODS: This work described the visual cells in the photoreceptor layer of the retinae of treeshrew (Tupaia belangeri chinensis) living on the high plateau of Yunnan, China, via scanning electron microscopy. RESULTS: Results indicated five morphologically different types of cones, two of which contain oil droplets in their inner segments. To our knowledge, no prior studies have reported oil droplets in the visual cells of higher mammals, only in lower vertebrate and primitive mammals. In addition, this study revealed one type of degenerative visual cell without outer segments. CONCLUSIONS: The findings signal the needs for additional studies to understand the physiological functions and phylogenetic relationships of the diversity of visual cells in this group of mammal.

Outcomes of adolescents with acute lymphoblastic leukaemia.

INTRODUCTION: Compared with young children who have acute lymphoblastic leukaemia (ALL), adolescents with ALL have unfavourable disease profiles and worse survival. However, limited data are available regarding the characteristics and outcomes of adolescents with ALL who underwent treatment in clinical trials. The aim of this study was to investigate the causes of treatment failure in adolescents with ALL. METHODS: We retrospectively analysed the outcomes of 711 children with ALL, aged 1-18 years, who were enrolled in five clinical trials of paediatric ALL treatment between 1993 and 2015. RESULTS: Among the 711 children with ALL, 530 were young children (1-9 years at diagnosis) and 181 were adolescents (including 136 younger adolescents [10-14 years] and 45 older adolescents [15-18 years]). Compared with young children who had ALL, adolescents with ALL were less likely to have favourable genetic features and more likely to demonstrate poor early response to treatment. The 10-year overall survival and event-free survival rates were significantly lower among adolescents than among young children (77.9% vs 87.6%, P=0.0003; 69.7% vs 76.5%, P=0.0117). There were no significant differences in the 10-year cumulative incidence of relapse, but the 10-year cumulative incidence of treatment-related death (TRD) was significantly greater among adolescents (7.2%) than among young children (2.3%; P=0.002). Multivariable analysis showed that both younger and older adolescents (vs young children) had worse survival and greater incidence of TRD. CONCLUSION: Adolescents with ALL had worse survival because they experienced a greater incidence of TRD. There is a need to investigate optimal treatment adjustments and novel targeted agents to achieve better survival rates (without excessive toxicity) among adolescents with ALL.

Space-Time Cluster's Detection and Geographical Weighted Regression Analysis of COVID-19 Mortality on Texas Counties.

As COVID-19 run rampant in high-density housing sites, it is important to use real-time data in tracking the virus mobility. Emerging cluster detection analysis is a precise way of blunting the spread of COVID-19 as quickly as possible and save lives. To track compliable mobility of COVID-19 on a spatial-temporal scale, this research appropriately analyzed the disparities between spatial-temporal clusters, expectation maximization clustering (EM), and hierarchical clustering (HC) analysis on Texas county-level. Then, based on the outcome of clustering analysis, the sensitive counties are Cottle, Stonewall, Bexar, Tarrant, Dallas, Harris, Jim hogg, and Real, corresponding to Southeast Texas analysis in Geographically Weighted Regression (GWR) modeling. The sensitive period took place in the last two quarters in 2020 and the first quarter in 2021. We explored PostSQL application to portray tracking Covid-19 trajectory. We captured 14 social, economic, and environmental impact's indices to perform principal component analysis (PCA) to reduce dimensionality and minimize multicollinearity. By using the PCA, we extracted five factors related to mortality of COVID-19, involved population and hospitalization, adult population, natural supply, economic condition, air quality or medical care. We established the GWR model to seek the sensitive factors. The result shows that adult population, economic condition, air quality, and medical care are the sensitive factors. Those factors also triggered high increase of COVID-19 mortality. This research provides geographical understanding and solution of controlling COVID-19, reference of implementing geographically targeted ways to track virus mobility, and satisfy for the need of emergency operations plan (EOP).

Primary anorectal malignant melanoma: A clinical, radiology and pathology correlation.

INTRODUCTION: Primary gastrointestinal melanomas are mucosal malignancies that arise from melanocytes in the oropharynx, rectum, and anus. Anorectal malignant melanoma (ARMM) are exceedingly rare, accounting for less than 1% of all melanomas, 0.1% of all rectal malignancies and 4% of anal malignancies. Diagnosis is frequently delayed as these lesions are often mistaken for haemorrhoids. Histological evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Due to the aggressive nature, 61% of patients with ARMM would already have lymph node involvement or distant metastases, by the time of diagnosis. Prognosis is usually poor with 5-year survival rate of <20%. We report a case of metastatic ARMM in an elderly lady who presented with symptoms and signs mimicking a haemorrhoid. CASE REPORT: A 69-year-old lady presented with one year history of intermittent rectal bleed and an anorectal mass that was initially treated as haemorrhoid. Colonoscopy showed a hyperpigmented mass in the anorectal region which was confirmed as malignant melanoma on histopathological examination. Imaging with CT and MRI demonstrated locally advanced tumour with distant metastases to the liver and lung. Patient was referred for palliative management. CONCLUSION: ARMM is a rare malignancy and often presented with non-specific clinical signs. Diagnosis is frequently delayed without high index of suspicion. MRI pelvis is the imaging of choice to assess local extent of disease. Histologic evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Prognosis is poor despite surgical and chemotherapeutic interventions.

Brain death in children: a retrospective review of patients at a paediatric intensive care unit.

PURPOSE: Among patients in paediatric intensive care units (PICUs), death is sometimes inevitable despite advances in treatment. Some PICU patients may have irreversible cessation of all brain function, which is considered as brain death (BD). This study investigated demographic and clinical differences between PICU patients with BD and those with cardiopulmonary death. METHODS: All children who died in the PICU at a university-affiliated trauma centre between October 2002 and October 2018 were included in this retrospective study. Demographics and clinical characteristics were compared between patients with BD and patients with cardiopulmonary death. RESULTS: Of the 2784 patients admitted to the PICU during the study period, 127 died (4.6%). Of these 127 deaths, 22 (17.3%) were BD and 105 were cardiopulmonary death. Length of PICU stay was shorter for patients with cardiopulmonary death than for patients with BD (2 vs 8.5 days, P=0.0042). The most common mechanisms of injury in patients with BD were hypoxic-ischaemic injury (40.9%), central nervous system infection (18.2%), and traumatic brain injury (13.6%). The combined proportion of accident and trauma-related injury was greater in patients with BD than in patients with cardiopulmonary death (27.3% vs 3.8%, P<0.001). Organ donation was approved by the families of four of the 22 patients with BD (18.2%) and was performed successfully in three of these four patients. CONCLUSIONS: These findings emphasise the importance of injury prevention in childhood, as well as the need for education of the public regarding acceptance of BD and support for organ donation.

Fatal spontaneous rupture of splenic artery aneurysm in third trimester pregnancy.

INTRODUCTION: Unforeseen emergency in late pregnancy can be catastrophic and cause unexpected maternal and foetal demise. Moreover, lack of awareness and failure of prompt treatment raise mortality rate. Such fatalities warrant a forensic autopsy as it may raise redundant medico-legal concerns. CASE REPORT: We report a case that revealed significant intra-abdominal haemorrhage at autopsy. The source of haemorrhage was at the spleen hilum and histology established rupture of splenic artery aneurysm. There was no associated obstetric cause found. CONCLUSION: Knowledge of spontaneous rupture of splenic artery aneurysm in late pregnancy is essential for monitoring maternal and foetal, morbidity and mortality. However, in the eventuality of death a comprehensive forensic autopsy is the only investigation to recognise such calamity and clear clinical confusion.

Treatment of cutaneous angiosarcoma of the scalp and face in Chinese patients: local experience at a regional hospital in Hong Kong.

INTRODUCTION: Angiosarcoma is a rare aggressive sarcoma that occurs mostly in the skin of the head and neck in the elderly population. The optimal management is dubious and most studies are from Caucasian populations. We aimed to examine the treatment and outcome of this disease in Chinese patients. METHODS: Data of patients with histopathologically verified cutaneous angiosarcoma of the head and neck during December 1997 to September 2016 were retrieved from our hospital cancer registry. The demographic data, clinicopathological information, modality of treatment, and outcomes were reviewed. RESULTS: During the study period, 17 Chinese patients were treated. Their median age was 81 years. The tumours were present in the scalp only (n=11), face only (n=4), or both scalp and face (n=2). Only two patients had distant metastases. The modalities of treatment were surgery (n=6), surgery and adjuvant radiotherapy (n=1), palliative radiotherapy (n=5), or palliative chemotherapy (n=3). The remaining two patients refused any treatment initially. Of the seven patients treated surgically, there were four local and two regional recurrences. The median time to relapse was 7.5 months. Overall, 16 patients had died; causes of death were disease-related in 12 whereas four other patients died of inter-current illnesses. One patient was still living with the disease. The median overall survival was 11.1 months and the longest overall survival was 42 months. CONCLUSION: The outcome of angiosarcoma in our series is poor. A high index of suspicion is mandatory for prompt diagnosis. Adjuvant radiotherapy is recommended following surgery. The benefit and role of systemic treatment in various combinations with surgery or radiotherapy require further study.

Mesh erosion to urinary bladder causing fistulation to abdominal wall resulting in necrotizing fasciitis: A case report of late complication of incisional hernia.

INTRODUCTION: Incisional hernia is not an uncommon complication after abdominal operation, and laparoscopic ventral hernia repair with mesh is commonly performed nowadays. It is thought to have less complication compare to the traditional open repair, yet late complication is still observed occasionally and can be disastrous. CASE REPORT: We hereby report a case of abdominal wall necrotizing fasciitis 21 months after laparoscopic incisional hernia repair in lower midline with dual mesh, due to mesh migration and erosion into urinary bladder, resulting in fistulation between bladder and abdominal wall. Repeated debridement and removal of mesh was required for sepsis control and the patient required intensive care support due to multi-organ failure. Subsequent repair of urinary bladder and abdominoplasty was performed after condition stabilized. CONCLUSION: This case was the first reported incident with bladder erosion by dual mesh causing vesico-cutaneous fistula complicated with necrotizing fasciitis. Although dual mesh theoretically reduces the risk of mesh erosion, mesh erosion to viscera can still happen and cause severe complication. Its risk should be balanced and discussed with patient with full consent.

Filariasis in axillary lymph node.

A case of adult filarial worms detected in an axillary lymph node of an asymptomatic patient. A 64 year-old Indian female underwent a mammogram and was incidentally found to have punctate microcalcifications in the upper outer quadrant of the left breast with left axillary lymphadenopathy. She has underlying hypertension and diabetes mellitus on oral medications. She has no family history of breast malignancy. Fine needle aspiration of the left axillary lymph node was suggestive of reactive lympha-denitis. Histopathological examination of excisional biopsy of left breast lump showed fibrocystic disease; no evidence of malignancy was detected whereas excisional biopsy of left axillary lymph node showed reactive lymphoid hyperplasia, featuring variably sized lymphoid follicles with intact mantle zone. No expansion of marginal zone was noted. Occasional pigment-laden macrophages were seen. One of the lymph node showed presence of calcified serpinginous tubular bodies, in keeping with non viable parasite organisms with intact outlines of the structures. There were no eosinophilic infiltrates. The possibility of filarial infestation was suspected. Histopathological sample was sent for further identification and confirmed the presence of adult filarial worm.