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.

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.

Impaired host defense against XC cell-induced tumors in thymectomized and in bursectomized chickens.

XC cells originally derived from the tumor of a rat previously inoculated with the Prague strain of Rous sarcoma virus were used to induce tumors in chickens surgically thymectomized or bursectomized in the newly hatched period. Thymectomized chickens had a significantly higher incidence of tumors, larger tumors, and a higher tumor mortality, compared with control chickens, when both groups were given 5 X 10(6) XC cells into the wing webs. Bursectomy could significantly influence the tumor size only. It appeared that the capacity of XC cells to induce tumors and the growth of such tumors were subject to immunological influence, with the thymus playing a major and the bursa of Fabricus a minor role under the conditions used.

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.

Evaluation of human cytomegalovirus gene expression in thoracic organ transplant recipients using nucleic acid sequence-based amplification.

BACKGROUND: Human cytomegalovirus (CMV) infection is a major cause of morbidity in transplant patients. Early diagnosis and treatment have been shown to improve outcome. We evaluated the suitability of CMV immediate early, early, and late gene expression detected by nucleic acid sequence-based amplification (NASBA) as markers of CMV infection. METHODS: Blood samples were taken immediately before transplant and every one to two weeks after transplantation for 12 weeks from 50 patients undergoing thoracic organ transplantation. CMV-NASBA was performed and results compared with serology, CMV pp65 antigenaemia (CMV-AG) and the development of clinical CMV infection. Patients received "preemptive" anti-CMV therapy with ganciclovir based on the CMV-AG results. RESULTS: CMV immediate early and early gene expression were detected in 87 and 47%, respectively, of patients without other evidence of CMV infection. CMV late gene expression had a sensitivity of 97% for infection (compared with 83% for CMV-AG P=0.06) and a specificity of 93% (compared with 100% P=NS). Late gene expression occurred at the same time as CMV antigenaemia but 1.1 weeks earlier than the threshold of antigenaemia (CMV-AG>10) used to initiate preemptive therapy. CONCLUSION: NASBA provided a standardized tool for the detection of CMV transcripts with a greater sensitivity than the standard antigenemia test. Detection of immediate early and early gene transcripts was not specific for subsequent infection. CMV late gene expression determined by NASBA was an accurate and early marker of CMV infection. Detection of CMV late gene expression could be used to trigger "preemptive" anti-CMV therapy.

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.

Chemotactic activities of avian lymphocytes.

Chicken lymphocytes, enriched chicken T and B lymphocytes, and a turkey B-lymphoblastoid cell line, the RP-9 cells, are used in the studies of chemotaxis in a Boyden-type chamber assay. The chemoattractants used are lipopolysaccharide, fMLP, interleukin-8, MIP1-beta, rabbit anti-chicken IgG and IgM. The results indicate that all these cells can migrate into the polycarbonate membranes in the absence of chemoattractants. When the chemoattractants are present, the numbers of migrating cells are greatly increased. It is, therefore, concluded that avian lymphocytes have the ability to migrate, and can respond to chemical signals which result in chemotaxis and accumulation of lymphocytes at the sites where the signals originate.

Significance of reverse transcription polymerase chain reaction in the detection of human cytomegalovirus gene transcripts in thoracic organ transplant recipients.

BACKGROUND: Cytomegalovirus disease is a major cause of morbidity in transplant recipients. We have evaluated the clinical value of detecting viral mRNA transcripts for the diagnosis of active infection leading to disease in recipients of thoracic organ transplants. METHODS: Blood samples from 10 transplant recipients were analyzed before transplantation and weekly after transplantation for 12 weeks. The profile of viral immediate-early, early, and late gene expression was determined by the reverse transcription polymerase chain reaction and compared with cytomegalovirus (pp65) antigenemia and host antibody status (serologic study). RESULTS: Two patients showed no active cytomegalovirus infection, one had asymptomatic infection detected serologically and seven patients had development of symptomatic infection with a significant serologic change. Viral immediate-early mRNA transcript was detectable in all 10 patients, including the two with no active infection. Early and late gene expression occurred in seven patients who were all antigenemia positive and in whom disease developed. Of the seven patients with development of antigenemia, six showed viral early and late gene expression before pp65 antigenemia, whereas one patient showed antigenemia before early and late gene expression. CONCLUSION: We have shown that the detection of viral early and late gene expression by reverse transcription polymerase chain reaction can act as diagnostic markers of cytomegalovirus disease with expression of early gene preceding the detection of antigenemia in most cases. In contrast, viral immediate early gene expression did not correlate with clinical infection. This diagnostic approach could be useful in the treatment of thoracic organ transplant recipients.

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.

Immunomagnetic separation of Cryptosporidium parvum oocysts using MACS MicroBeads and high gradient separation columns.

We evaluated the MACS immunomagnetic separation (IMS) system for concentrating Cryptosporidium parvum. Oocysts were first labeled with fluorescein isothiocyanate (FITC) or rabbit anti-C. parvum antibodies, then linked to MicroBeads coated with anti-FITC or anti-rabbit IgG, and separated through a high gradient separation column. Results indicated that over 95% of oocysts were recovered and their fluorescence and infectivity were retained. The presence of MicroBeads showed no effect on genomic DNA extraction and subsequent polymerase chain reaction (PCR)-based analyses, as sensitivity of PCR (10 oocysts) and the band pattern of randomly amplified polymorphic DNA (RAPD) were identical to those using DNAs extracted from normally purified oocysts. IMS-PCR consistently detected as few as 10 oocysts from 100 ml of apple juice or homogenized milk and IMS-IFA could detect 100 oocysts from 1 g of deer manure, demonstrating the efficiency of IMS in recovering oocysts from environmental and food samples. Our results suggest that the MACS IMS system could be used for multiple applications in Cryptosporidium research.

Intestinal obstruction and gastrointestinal bleeding due to systemic amyloidosis in a woman with occult plasma cell dyscrasia.

A 60-year-old woman presented to our hospital with repeated vomiting. Upper gastrointestinal endoscopy revealed a 1 cm diameter ulcer with clean base on the roof of the gastric antrum. Histological examination of gastric biopsies revealed abundant amorphous eosinophilic deposits in the submucosa. Congo red stain for amyloid was positive. A barium follow-through study revealed a mass in the jejunum causing incomplete obstruction. Urine for Bence Jones protein was negative. Serum protein electrophoresis did not reveal any abnormal band and serum immunoelectrophoresis did not detect any monoclonal immunoglobulin. Bone marrow examination, however, revealed an increased proportion of plasma cells. Subsequent immunohistochemical staining demonstrated monoclonal lambda light chains in the marrow plasma cells, thereby confirming a plasma cell dyscrasia. Amyloidosis involving the gastrointestinal tract can produce a wide variety of non-specific symptoms and signs. A high index of suspicion is necessary to arrive at an early diagnosis. Management consists of supportive therapy for the gastrointestinal tract as well as treatment of the underlying condition.

Cytomegalovirus in transplantation: new developments.

The control of cytomegalovirus infection and disease continues to be a major problem in transplantation and different strategies have been developed to reduce its incidence. Early diagnosis of infection soon after transplantation, using molecular tools such as the polymerase chain reaction, have resulted in successful clinical trials using the strategy of pre-emptive therapy. Adoptive transfer of immune cells, which are predominantly the cytomegalovirus-specific cytotoxic T lymphocytes, into transplant recipients has been shown to restore effective immunity. A vaccine preparation has been in development aimed at preventing primary infections in allograft recipients though effective protection has yet to be shown. The mechanisms of viral pathogenesis in chronic graft rejection remain unclear; however, recent contributions from the field of cell biology have increased our understanding of possible processes which have the potential for application in the field of gene therapy for the treatment of disease.

Apoptosis in chicken embryo fibroblasts caused by Newcastle disease virus.

The GB strain of Newcastle disease virus (NDV) was used to infect chicken embryo fibroblasts (CEF). At various times after infection, CEF were harvested and processed for DNA extraction, flow cytometry and electron microscopy. Agarose gel electrophoresis of the DNA at 12 h after infection, showed a laddering pattern, indicating fragmentation of cellular DNA. Flow cytometry analysis of the infected cells showed an increase in the population of smaller cells (apoptotic cells). Electron microscopic examination showed extensive cellular necrosis, but also showed some other cells with condensed chromatin and with extensive perinuclear fragmentation of chromatin; apoptotic bodies could also be readily seen. These data suggest that NDV infection of CEF causes apoptosis, in addition to necrosis.

A cytotoxicity test for the detection of Campylobacter jejuni toxin.

A 7-h 51Cr-release cytotoxicity assay has been developed to detect the presence of Campylobacter jejuni toxin in the culture supernatant. Some of the culture supernatants have cytotoxic effects against labeled chicken lymphocytes, while some others do not have this effect. There is no direct correlation between the pathogenicity of the organisms and the presence of the toxin. The supernatant of C. jejuni retains its cytotoxicity after heating at 100 degrees C for 10 min.; therefore, it is a heat stable toxin.

Resistance of chickens immunized against Mycoplasma gallisepticum is mediated by bursal dependent lymphoid cells.

Newly hatched chickens were significantly protected against challenge by the virulent S6 strain of Mycoplasma gallisepticum after vaccination with the TS 100 mutant. Removal of the thymus did not abolish the protective effect of the vaccine, but removal of the bursa of Fabricius did. The results suggest that the resistance induced by vaccine is mediated by the bursal-dependent lymphoid cells.

Vaccination of cyclophosphamide-treated chickens against Newcastle disease virus infection.

Newly-hatched chickens were treated with 3 mg of cyclophosphamide (CY) per day for 4 consecutive days. At 2 weeks of age, these chickens, together with a group of untreated controls, were vaccinated intranasally or subcutaneously with the La Sota strain of Newcastle disease virus (NDV). All chickens were challenged intranasally with the GB strain of NDV 2 weeks later. CY-treated, intranasally vaccinated chickens were highly resistant to NDV challenge, yet none of the chickens produced any detectable humoral antibodies to NDV; antibodies to NDV were detectable in the tracheal washings, however.

Induction of lymphocyte agglutination and lysis by Newcastle disease virus.

Five strains of Newcastle disease virus (NDV) were tested for their ability to agglutinate and lyse chicken lymphocytes. All 5 strains agglutinated lymphocytes, and the agglutination was inhibited by anti-NDV sera. All 5 strains also caused a different degree of direct virus-induced lysis of 51Cr-labeled chicken lymphocytes. This direct lymphocyte cytotoxicity was lost after heating at 56 degrees C for 30 min, or after treatment with a high concentration of formalin (1:100 dilution). Neither a low concentration of formalin (1:5000) nor trypsin treatment had any effect on cytotoxicity.