Emergency attendances and hospitalisations for complications after transrectal ultrasound-guided prostate biopsies: a five-year retrospective multicentre study.

INTRODUCTION: Transrectal ultrasound-guided (TRUS) prostate biopsy is an established procedure for diagnosis of prostate cancer. Complications after TRUS biopsy are not well reported in Hong Kong. This study evaluated the 5-year incidences of TRUS biopsy complications and potential risk factors for those complications. METHODS: This was a retrospective review of biopsies performed from 2013 to 2017 in two local hospitals, using data retrieved from electronic medical records. The primary outcome was the occurrence of complications requiring either emergency attendances or hospitalisations within 30 days after biopsy. Potential risk factors were examined using multiple logistic regression analysis. RESULTS: In total, 1699 men were included (mean age ± standard deviation: 67 ± 7 years; median prostate-specific antigen level: 7.9 µg/L [interquartile range, 5.5-12.6 µg/L]); 4.3% had pre-biopsy bacteriuria. Overall, 5.7% and 3.8% of post-biopsy complications required emergency attendances and hospitalisations, respectively. Gross haematuria and rectal bleeding requiring emergency attendances developed in 2.1% and 0.4% of men; 0.8% and 0.4% required hospitalisations. Furthermore, 1.5% of men developed acute urinary retention requiring hospitalisations; 1.9% and 1.2% had post-biopsy infections requiring emergency attendances and hospitalisations, respectively, and 0.9% had urosepsis requiring hospitalisations. Prostate volume >48 cc was associated with an increased risk of post-biopsy retention (odds ratio 2.75, 95% confidence interval: 1.23-4.17). CONCLUSIONS: The rate of overall complications after TRUS biopsy was low. The most common complications requiring emergency attendances and hospitalisations were gross haematuria and acute urinary retention, respectively. Prostate volume >48 cc increased the risk of post-biopsy urinary retention.

Statistical evaluation of bioretention system for hydrologic performance.

Long-term retention performance is a common performance indicator for low-impact development practices, such as rain barrels, rain gardens, and green roofs. This paper introduces a numerical approach for the estimation of annual retention ratios of stormwater by bioretention. The annual retention ratio is taken as the ratio of the annual accumulated volume of stormwater retained by bioretention over the total volume of runoff draining into the system. The hydrologic model Storm Water Management Model (SWMM) is used to simulate the relevant flows of a bioretention system with parametric variations of the watershed area ratio and hydraulic conductivity of the soil media. Under these two dominant performance-governing parameters, retention ratios are calculated using the 10-year (2004-2013) rainfall record in Hong Kong at 1-min intervals. This indicator can be readily applied to estimate the long-term retention performance of a bioretention using particular values of watershed area ratio and hydraulic conductivity of soil media under the climate of Hong Kong. The study also analyzes the influence of variation of annual precipitation on the estimated retention performance. Flow data monitored on a pilot-scale physical model of bioretention during a number of rainfall events are used to validate the numerical simulation.

Investigation of the shape change of bio-flocs and its influence on mass transport using particle image velocimetry.

In this laboratory study, an advanced flow visualization technique - particle image velocimetry (PIV) - was employed to investigate the change of shape of activated sludge flocs in water and its influence on the material transport characteristics of the flocs. The continuous shape change of the bio-flocs that occurred within a very short period of time could be captured by the PIV system. The results demonstrate that the fluid turbulence caused the shift of parts of a floc from one side to the other in less than 200 ms. During the continuous shape change, the liquid within the floc was forced out of the floc, which was then refilled with the liquid from the surrounding flow. For the bio-flocs saturated with a tracer dye, it was shown that the dye could be released from the flocs at a faster rate when the flocs were swayed around in water. The experimental results indicate that frequent shape change of bio-flocs facilitates the exchange of fluid and materials between the floc interior and the surrounding water. This mass transfer mechanism can be more important than molecular diffusion and internal permeation to the function and behavior of particle aggregates, including bio-flocs, in natural waters and treatment systems.

A curvelet-based morphological segmentation of abdominal CT images.

This paper presents a segmentation methodology of abdominal axial CT images. The aim of the study is to determine the location of mesenteric area from the axial images so the organs enclosed within can be localized precisely for diagnostic purposes. The challenge confronted here is that there is no a certain deterministic shape of abdominal organs. The methodology implemented here utilizes a curvelets stage followed by morphological image processing to achieve a contour emphasized segmentation from the gestalts of surrounding organs. This paper gives a detailed analysis of approach taken with the problems faced and a brief comparison wrt to other wavelet approaches.

Laparoscopic radical prostatectomy: single centre experience after 5 years.

OBJECTIVE: To summarise our experience of laparoscopic radical prostatectomy in a single centre in Hong Kong over 5 years. DESIGN: Retrospective study. SETTING: Urology Division, Department of Surgery, Tuen Mun Hospital, Hong Kong. PATIENTS: A total of 87 patients who underwent laparoscopic radical prostatectomy from March 2002 to May 2007. MAIN OUTCOME MEASURES: Peri-operative data and follow-up information. RESULTS: The operative procedure used entailed Montsouris technique and its modifications, including the latest method involving the extraperitoneal descending technique. In all, 87 patients underwent the operation; in two, the procedure was converted to open surgery. Peri-operative parameters which showed improvement included: operating time, blood loss, resort to blood transfusions, and the complication rate. There was no operation-related mortality. In organ-confined disease, a clear surgical margin was achieved in 93% of the patients, but in those whose disease was not organ-confined, the positive margin rate was 87%. Among patients with organ-confined disease, 13% had evidence of biochemical recurrence. Hormonal therapy was started in five patients, none of whom died during the follow-up period (mean, 24 months). Continence recovered in 69% of the patients by 6 months and in 92% by 12 months post-surgery. Assessment of erectile function before and after the surgery was problematic and estimated to be 20% among patients having the nerve-sparing procedure performed. CONCLUSION: Although Hong Kong has a relatively low incidence for prostate cancer, it was possible to develop laparoscopic radical prostatectomy with acceptable early results. Further follow-up is warranted before formulating definitive conclusions about this procedure.

'Street ketamine'-associated bladder dysfunction: a report of ten cases.

Ten young ketamine abusers presented with lower urinary tract symptoms to two regional hospitals in Hong Kong. Investigations demonstrated contracted bladders and other urinary tract abnormalities. These types of findings have never been reported before in ketamine abusers. The possible aetiology is also discussed.

Chemotaxis in Mycoplasma gallisepticum.

Boyden-type chemotactic chambers were used to demonstrate that Mycoplasma gallisepticum (MG) was capable of migrating into chemotactic membranes. Scanning electron microscopy was used to confirm that MG could penetrate the membranes. To further demonstrate the invasive ability of MG, MG was deposited on the shell membranes of 9-day-old chicken embryos, and after 6 days of incubation, the presence of MG DNA in the allantoic fluids was detected by polymerase chain reactions. These results indicate that MG can penetrate cellular membrane, possibly by going through the porous cellular surface.

Morphologic changes in chicken cells after in vitro exposure to Mycoplasma gallisepticum.

Mycoplasma gallisepticum (MG) was used to expose chicken peripheral blood lymphocytes (PBLs), red blood cells (RBCs), heterophils, and chicken tumor cells (MSB-1 and HD-11 cells). Incubation of PBLs with MG for 3 hr resulted in extensive clumping of lymphocytes. Incubation of the MSB-1 cells with MG also caused clumping of the cells, with many of the cells showing perforations and others showing capping of the surface projections. Incubation of RBCs with MG resulted in an altered cell surface morphology, a decrease in cell size, and perforation. There were no discernible changes on the surface of the heterophils and the HD-11 cells. However, the HD-11 cells appeared to have a decreased ability to attach to the surface of the plastic and to have a decreased ability to respond to chemoattractant fMLP after 24 hr of incubation. These results suggest that, under the conditions used, MG caused certain damage to peripheral blood cells and a significant decrease in chemotactic response in the HD-11 cells.

Mycoplasma meleagridis-induced lesions in the tarsometatarsal joints of turkey embryos.

Mycoplasma meleagridis (MM) has the ability to cause bone deformity in turkey poults. However, few pathological lesions have been described and no evidence of MM-induced damage to the bones has been shown. In this study, 17-day-old turkey embryos were inoculated with MM into the allantoic cavity. On the 27th day, eight of the 22 embryos presented with curved toes. Scanning electron microscopy of the tarsometatarsal joints showed fissures in the cartilage. Histological sections of the joints revealed only the infiltration of cells with eosinophilic granules. Immunohistochemical staining (IHS) showed the presence of MM in the aggregates of the bone marrow cells and the cells with eosinophilic granules. Some of these cells were harvested by laser capture microdissection (LCM), lysed, and used as template DNA. With a pair of MM-specific primers in a conventional polymerase chain reaction (PCR), a gene product was amplified, and it comigrated with the MM DNA, which indicates that these captured cells contained MM DNA. Thus, this research shows that inoculation of MM into the turkey embryos produced joint lesions and caused cellular infiltration within the bones.

Mycoplasma gallisepticum--induced alterations in cytokine genes in chicken cells and embryos.

Mycoplasma gallisepticum (MG) was used to infect the MSB-1 cells, the HD-11 cells, and chicken embryos. The RNA from these cells and the embryonic spleen cells were extracted and assayed for the expression of cytokine genes using reverse transcription-polymerase chain reaction. The results showed that MG infection suppressed the expression of the IL-8 gene in the MSB-1 cells and enhanced the expression of the IL-8 and IL-6 genes in the HD-11 cells; a slightly increased expression of macrophage inflammatory protein-1beta (MIP-1beta) in MG-infected spleen cells was noted. Because of the divergent response in cytokine expression in different cell types, more work needs to be done before a correlation between the cytokine gene expression and the pathogenesis of a disease can be made.

Pathogenicity of Mycoplasma meleagridis for chicken cells.

Mycoplasma meleagridis (MM) is a known pathogen for turkeys only. In this study, MM was used to inoculate chicken embryos and tumor cells to assess its pathogenic potential for chickens. In chicken embryos, it caused abnormal-shaped toes and severely denuded tracheae. In chicken tumor cells, MM reduced the cellular capacity to release a chemoattractant that causes the migration of heterophils. MM also caused death and/or a reduced growth rate in chicken HD-11 cells, a macrophage-monocyte-derived cell line. Thus, the data show that MM is a potential pathogen for chicken embryos and chickens cells. Further exploration to determine the pathogenicity in chickens may be warranted.

Interactions between the membranes of turkey cells and Mycoplasma meleagridis.

We used Myoplsma meleagridis (MM) to infect the RP-9 cells and the eggshell membranes and scanning electron microscopy (SEM) and confocal microscopy to study the interactions between the organisms and the cell surfaces. The surface of the RP-9 cells contained numerous projections. After 24 hr of infection with MM, those projections were either lost or aggregated to the side; MM-like particles could be seen on the surface of the cells, and surface fluorescence could be detected by confocal microscopy. On the surface of MM-infected shell membranes were necrotic fibrous tissues and cells detected by SEM and an intense surface fluorescence detected by confocal microscopy. These results indicate that MM infection of the cell surface can result in cellular damage.

Infection of the turkey embryonic trachea with Mycoplasma meleagridis.

Mycoplasma meleagridis was used to infect turkey embryos and tracheal explants. In the embryonic trachea, there was a decrease in the number of cilia and the sloughing of epithelial cells. In the tracheal explants, the deciliation was more severe and erosion of the tracheal surface was also evident; additionally, the cells of the trachea showed prominent perforation. These results indicate that M. meleagridis infection can result in damage to cells and to the surface of the trachea, which may have pathological consequences.

Mycoplasma gallisepticum-induced alterations in chicken red blood cells.

Incubation of Mycoplasma gallisepticum with washed chicken red blood cells for 1 hr or 5 hr resulted in altered red blood cell surface morphology and perforations of the cells.

Scanning electron microscopic studies of Mycoplasma gallisepticum infection in embryonic tracheae.

Mycoplasma gallisepticum (MG) was used to infect chicken embryos, and scanning electron microscopy was used to examine the morphologic changes in the tracheae. Tracheae harvested from embryos infected with MG for 5 days showed extensive deciliation, surface erosion, and inflammatory cell infiltration. Embryonic tracheal explants infected with MG for 6 hr showed the same deciliation and surface erosion. The damage to the tracheal surface caused by MG at the embryonic stage might play a role in the pathogenesis of MG infection.

Newcastle disease virus-induced damage to embryonic tracheae and red blood cells.

Newcastle disease virus (NDV)-induced damage to the embryonic chicken trachea, the tracheal explants, and red blood cells (RBCs) was studied by scanning electron microscopy. In the tracheae, NDV caused deciliation and depletion of the epithelial cells. In the tracheal explants, the same pathologic changes could be seen within 6 hr of virus infection. In RBCs, a perforation and a change in surface morphology were observed.

Chemotactic response of lymphocytes in chicken embryos infected with Mycoplasma gallisepticum.

A prominent feature of Mycoplasma gallisepticum (MG) infection is a lymphoproliferative response at the site of infection. In this study, artificial air cells (AACs) were made in eggs containing 16-day old chicken embryos. An MG culture and supernates from MG-infected RP-9 cells, HD-11 cells and monocytes were separately deposited on the membranes of the AAC. After incubation for 5 days, the eggs were opened and the AAC membranes were collected for histopathological examinations. Immunolabelling of MG-infected membranes showed a massive infiltration of lymphocytes possessing CD3 surface markers and the presence of cells that secreted lymphotactin, a chemokine. The supernates from MG-infected cells caused the infiltration of comparatively small numbers of lymphocytes. The culture medium-inoculated AACs had no obvious abnormalities of the membranes. It is suggested, therefore, that MG infection of the embryonic membranes causes the embryos to secrete lymphotactin, which induces the migration and accumulation of lymphocytes to the sites of infection.

The cytolytic effects of Salmonella enterica serovar Typhimurium on chicken heterophils.

Mixing of chicken heterophils and Salmonella enterica serovar Typhimurium resulted in a rapid disappearance of heterophils when examined by scanning electron microscopy and trypan blue dye exclusion test. This disappearance appeared to be caused by a rapid degranulation of heterophils.

The macrophage inflammatory protein-1beta in the supernatants of Mycoplasma gallisepticum-infected chicken leukocytes attracts the migration of chicken heterophils and lymphocytes.

Chicken monocytes, macrophages, heterophils and thrombocytes were infected with Mycoplasma gallisepticum, and their supernatants were collected and tested for the presence of chemotactic activities. The supernatants from MG-infected monocytes and macrophages were able to attract the migration of both heterophils and lymphocytes. The chemotactic activity in these supernatants could be abolished by antibodies prepared against the 10 amino acid peptides of the macrophage inflammatory protein (MIP)-1beta, indicating that the released chemoattractant was a MIP-1beta-like compound. The supernatant from MG-infected heterophils was also able to attract the migration of chicken lymphocytes, but its activity could not be neutralized by the antibody to MIP-1beta, indicating that the chemoattractant is not related to MIP-1beta. The supernatants from both control and MG-infected thrombocytes were able to attract the migration of lymphocytes. These results indicate that there is more than one chemotactic factor that is released by these cells; one of the chemoattractants has been identified as a MIP-1beta. These results also show that MIP-1beta may play a role in the recruitment and accumulation of heterophils and lymphocytes to the sites of mycoplasma infection.

alpha-1 antitrypsin phenotypes by isoelectric focusing in a metropolitan southern Chinese population.

AIMS/BACKGROUND: alpha-1 antitrypsin (alpha1AT) is an abundant protease inhibitor in human plasma. Its phenotypic variability has been reported to be associated with pulmonary emphysema and chronic liver diseases. However, alpha1AT deficiency is an uncommon condition in the Chinese population. The aim of this study was to describe the phenotypic distribution of alpha1AT in a southern Chinese population. METHODS: A total of 1085 healthy blood donors underwent alpha1AT phenotyping by isoelectric focusing. RESULTS: Two thirds (66.1%) were homozygous for either M1 or M2, whereas 32.6% were heterozygous for two different M phenotypes. The frequency of allelic variants was only 0.007, and deficiency variants were absent. Compared with earlier studies on southern Chinese populations, this study found a lower frequency of M2, and a higher number of allelic variants, including E, L, N, P, and S. This phenomenon can be attributed to population migration and mixing. CONCLUSIONS: An understanding of the alpha1AT pattern is important for evaluating the predisposition of the population to selected clinical diseases.