Kidney Transplantation Outcomes From Uncontrolled Donation After Circulatory Death: A Systematic Review and Meta-analysis

BACKGROUND

Uncontrolled donation after circulatory death (uDCD) is a potential additional source of donor kidneys. This study reviewed uDCD kidney transplant outcomes to determine if these are comparable to controlled donation after circulatory death (cDCD).

METHODS

MEDLINE, Cochrane, and Embase databases were searched. Data on demographic information and transplant outcomes were extracted from included studies. Meta-analyses were performed, and risk ratios (RR) were estimated to compare transplant outcomes from uDCD to cDCD.

RESULTS

Nine cohort studies were included, from 2178 uDCD kidney transplants. There was a moderate degree of bias, as 4 studies did not account for potential confounding factors. The median incidence of primary nonfunction in uDCD was 12.3% versus 5.7% for cDCD (RR, 1.85; 95% confidence intervals, 1.06-3.23; P = 0.03, I2 = 75). The median rate of delayed graft function was 65.1% for uDCD and 52.0% for cDCD. The median 1-y graft survival for uDCD was 82.7% compared with 87.5% for cDCD (RR, 1.43; 95% confidence intervals, 1.02-2.01; P = 0.04; I2 = 71%). The median 5-y graft survival for uDCD and cDCD was 70% each. Notably, the use of normothermic regional perfusion improved primary nonfunction rates in uDCD grafts.

CONCLUSIONS

Although uDCD outcomes may be inferior in the short-term, the long-term outcomes are comparable to cDCD.

Systematic Review of Preoperative Prognostic Biomarkers in Perihilar Cholangiocarcinoma

Perihilar cholangiocarcinoma (pCCA) is an uncommon malignancy with generally poor prognosis. Surgery is the primary curative treatment; however, the perioperative mortality and morbidity rates are high, with a low 5-year survival rate. Use of preoperative prognostic biomarkers to predict survival outcomes after surgery for pCCA are not well-established currently. This systematic review aimed to identify and summarise preoperative biomarkers associated with survival in pCCA, thereby potentially improving treatment decision-making. The Embase, Medline, and Cochrane databases were searched, and a systematic review was performed using the PRISMA guidelines. English-language studies examining the association between serum and/or tissue-derived biomarkers in pCCA and overall and/or disease-free survival were included. Our systematic review identified 64 biomarkers across 48 relevant studies. Raised serum CA19-9, bilirubin, CEA, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and tumour MMP9, and low serum albumin were most associated with poorer survival; however, the cutoff values used widely varied. Several promising molecular markers with prognostic significance were also identified, including tumour HMGA2, MUC5AC/6, IDH1, PIWIL2, and DNA index. In conclusion, several biomarkers have been identified in serum and tumour specimens that prognosticate overall and disease-free survival after pCCA resection. These, however, require external validation in large cohort studies and/or in preoperatively obtained specimens, especially tissue biopsy, to recommend their use.

Evolution of laparoscopic pancreaticoduodenectomy at Westmead Hospital

BACKGROUND

Despite its proposed benefits, laparoscopic pancreaticoduodenectomy (LPD) has not been widely adopted due to its technical complexity and steep learning curve. The aim of this study was to report a single surgeon's experience in the stepwise implementation of LPD and evolution of technique over a nine-year period in a moderate-high volume unit.

METHODS

Carefully selected patients underwent LPD initially by hybrid approach (laparoscopic resection and open reconstruction), which evolved into a total LPD (laparoscopic resection and reconstruction). Data was prospectively collected to include patient characteristics, intraoperative data, evolution of technique and postoperative outcomes.

RESULTS

A total of 25 patients underwent hybrid LPD (HLPD) and 20 patients underwent total LPD (TLPD). There was no 90-day mortality. Three patients developed a postoperative pancreatic fistula (POPF), all of which occurred in patients undergoing HLPD. There was no POPF in 20 consecutive TLPD. There was no evidence of anastomotic strictures in the hepaticojejunostomy in patients undergoing TLPD at long term follow up.

CONCLUSION

A gradual and cautious progression from HLPD to TLPD is essential to ensure safe implementation into a unit. LPD should only be considered in carefully selected patients, with outcomes subjected to regular and rigorous independent audit.

Outcomes of endovascular, open surgical and autotransplantation techniques for renal artery aneurysm repair: a systematic review and meta-analysis

BACKGROUND

Renal artery aneurysms (RAA) can be repaired with endovascular exclusion (EVR), open repair (OR), or ex-vivo repair with renal autotransplantation (ERAT). This systematic review compares repair indications, aneurysm characteristics, and complications following these interventions.

METHODS

A systematic review of databases including MEDLINE, PUBMED, and EMBASE by two independent reviewers for studies from January 2000-November 2022. All studies evaluating repair indications, RAA morphology, morbidity and mortality following EVR, OR, and ERAT were included.

RESULTS

A total of 38 studies were included with 1540 EVR, 2377 OR and 109 ERAT subjects. Increasing aneurysm size, or diameters >20 mm, were the most common repair indications across EVR and OR (n = 537; 48%), and ERAT (n = 23; 52%). All ERAT repairs were at or distal to renal artery bifurcations (n = 46). Meta-analyses demonstrated significantly shorter length of stay (LOS) with EVR compared to OR (mean difference -4.06, 95% confidence interval (CI) -5.69 to -2.43, P < 0.001). No significant differences were found in mean aneurysm diameter (P = 0.23), total complications (P = 0.17), and mortality (P = 0.85). Major complications (Clavien-Dindo ≥III) across studies most commonly included acute renal failure (EVR 4.9% vs. OR 7.0%). Nephrectomy was the most common major complication in ERAT (5.5%).

CONCLUSIONS

Outcomes following EVR and OR of RAAs are comparable. EVR offers a shorter LOS, with no difference in morbidity or mortality. ERAT is currently only utilized for distal RAAs, however carries higher risk of infarction and nephrectomy necessitating specialized expertise or algorithms to assist appropriate selection of repair methods.

Outcomes of live renal donors with a history of nephrolithiasis; A systematic review

The clinical outcomes of kidney donors with a prior history of nephrolithiasis are poorly defined. We conducted a systematic review assessing the post-donation clinical outcomes of kidney donors with a history of nephrolithiasis. Electronic databases (Ovid and Embase) were searched between 1960 and 2021 using key terms and Medical Subject Headings (MeSH) - nephrolithiasis, renal stones, renal transplantation and renal graft. Articles included conference proceedings and journal articles and were not excluded based on patient numbers. Primary outcome was donor stone-related event. Secondary outcomes were renal function upon follow-up or post-operative nephrectomy complications. In summary, 340 articles were identified through database search. We identified 14 studies (16 cohorts) comprising 432 live donors followed up for a median of 26 months post live kidney donation. Six donors donated the stone-free kidney whilst 23 live donors had bilateral stones. Mean stone size was 4.2 ± 1.4 mm (1-16) with average follow up duration of 21.1 months (1-149). Twelve studies provided primary outcome (n = 138 patients) and eight (n = 348) for secondary outcomes. One donor had a stone-related event upon follow up. A total of 195 patients had eGFR <60 upon follow up. However, they were not significantly different when compared to renal function of live donors that didn't have pre-donation nephrolithiasis. Many of the studies couldn't provide long term follow up, coupled with limited data regarding the nature of the pre-donation stone disease. In conclusion, this systematic review shows that we have very limited information upon which to base recommendation regarding pre-donation risk of post-donation complications. Longer term follow up is required and lifelong follow up with live donor registries will aid further understanding.

Utilizing the same incision for staged renal transplant in patients with polycystic kidney disease requiring hand-assisted laparoscopic nephrectomy

BACKGROUNDS

Many autosomal dominant polycystic kidney disease (ADPKD) patients undergo nephrectomy and subsequent renal transplantation. We report our outcomes after hand-assisted laparoscopic nephrectomy (HALN) where a Rutherford-Morrison incision is used as a hand-port site and kidney extraction site, as well the future incision site for staged transplantation.

METHODS

A retrospective review was performed on all adult nephrectomies for ADPKD by the Transplant Surgery department at Westmead Hospital between June 2011 and June 2021. Outcomes were compared between HALN, laparoscopic nephrectomy (LN) and open nephrectomy (ON) including operation time, hospital length of stay (LOS), post-operative complications, subsequent transplantation and post-transplantation wound complications.

RESULTS

Twenty-two HALN, 8 LN and 5 ON were performed during the study period. Median kidney weights for HALN, LN and ON were significantly different (1575, 403, 3420 g respectively, P = 0.001). There was a significant difference in LOS between the HALN and ON (5.8 versus 9.8 days, P = 0.04), but not between HALN and LN (5.8 versus 5.1, P = 0.06). There was no significant difference for operation time (P = 0.34) and major complication rates (P = 0.58). There were 8 HALN, 5 LN and 2 ON who have had subsequent renal transplantation with one wound complication, an incisional hernia in the HALN group.

CONCLUSION

Our HALN is associated with a shorter LOS and similar complication rate to ON and can be efficiently performed for significantly larger kidneys than LN without a significant difference in operation time or LOS. The same Rutherford-Morrison incision site can be used for transplantation.

Transplant Outcomes From Deceased Donors Dying With Burns Injury, a Systematic Review

AIM

The ever-expanding organ supply and demand gap necessitates alternate sources of organ donors. Initially thought to be a contraindication, organ procurement from nonsurvivable burns patients is possibly an additional organ donor source. We aimed to conduct a systematic review investigating the prevalence and outcomes of the use of burn victims as a source of organ donation for transplantation.

METHODS

Medline and EMBASE were searched between 1990 and 2020, using the following keywords: organ procurement, organ donation, organ transplantation, and burns. Studies were not excluded based on patient numbers and included both published abstracts/conference proceeding and journal articles. Studies were excluded if specific organs were not identified or if posttransplant outcomes were not recorded. Primary and secondary outcomes of interest were post-transplantation organ function and complications respectively.

RESULTS

Six manuscripts met study inclusion criteria. Fourteen burns donors were identified, including both donation after circulatory death and donation after brain death pathways. The total body surface area of burn ranged from 4% to 90%. A total of 4 hearts, 2 lungs, 8 livers, 1 pancreas, and 24 kidneys were transplanted with varying duration of follow-up and outcomes.

CONCLUSION

A very small number of studies have reported the posttransplant outcomes of organs derived from victims of burn injury, including very limited information regarding graft function in the short or long term. Hence, recommendations for the utilization of organs from victims of burn injury should remain guarded and subject to surveillance.

Using Probability Estimates to Evaluate a Patient With Weakness

In this case report, we review how probabilistic reasoning can be implemented in retrospect to refine the diagnostic process. A 67-year-old female with a history of polymyalgia rheumatica (PMR) and a recent dental procedure presented with weakness, falls, and chills ongoing for two weeks. She reported pain in her shoulders and lower back. On presentation, she was febrile, and labs were notable for leukocytosis with neutrophilic predominance and an elevated erythrocyte sedimentation rate (ESR). Chest radiograph revealed a left lower lung opacity, which was not seen on a repeat film. She was treated with antibiotics for community-acquired pneumonia and steroids for an exacerbation of PMR. After eight days of hospitalization, she was transferred to a subacute rehabilitation facility. A month later, she was readmitted with worsening lower back pain and right lower extremity weakness. Imaging revealed discitis and osteomyelitis at L1-L2. A spinal epidural abscess was present, leading to severe compression of the cauda equina nerve roots. Aspirate was positive for group B streptococcus. With antibiotic treatment alone, she recovered with resolution of her weakness.

In reviewing the literature, it becomes evident where improvements could have been made in the diagnostic process. Fever, leukocytosis, and neurological weakness are not commonly associated with PMR exacerbations. Lack of cough or shortness of breath, a persistently elevated erythrocyte sedimentation rate and C-reactive protein despite antibiotic treatment, and a repeat chest radiograph without an opacity suggest an alternative diagnosis to pneumonia. Persistent back pain with an insidious onset is a feature of untreated spinal epidural abscess. Steroid use and dental procedures are possible risk factors for spinal epidural abscess. By shedding light on how probabilities should be estimated, we hope to encourage probabilistic thinking to improve diagnostic accuracy. As with the best political forecasters, making precise probability estimates and frequently updating them may improve diagnostic accuracy for clinicians.

Renal allograft compartment syndrome: a review

Renal allograft compartment syndrome (RACS) is the result of extrinsic compression resulting in graft dysfunction and loss due to ischaemia. A literature review was performed by computerized searches from the following data sources Medline, EMBASE, PubMed and Cochrane Library databases. Risk factors include size mismatch between graft and recipient. Intraoperative suspicion should be exercised if there is poor tissue turgor, cyanosis and loss of urine output upon fascial closure. Doppler ultrasound is the modality of choice amongst the literature to aid in diagnosis of RACS. From our study, the accepted form of treatment is early detection and appropriate surgical intervention. Nevertheless, it is clear from the paucity of literature that further investigation into this area of transplantation is necessary.

A diagnostic and management conundrum in a rare case of a small renal mass UTUC with IVC and bilateral renal vein tumour thrombus

Upper Tract Urothelial Carcinomas (UTUC) are generally uncommon, accounting for approximately 5% of all urinary tract tumours. This report describes a unique Case of a 52-year-old-male with no known risk factors or symptoms of UTUC, who presented with bilateral sub-massive pulmonary embolus (PE). Subsequent computed tomography (CT) demonstrated a small (<2cm) right cortical based mass a discordant venous tumour thrombus (VTT) extending in the IVC, up to the level of the hepatic vein and bilateral renal veins. The patient had surgical excision in the form of right radical nephroureterectomy, IVC resection with bovine pericardial graft reconstruction and left renal autotransplant.

How to repair a donor renal vein injury with an inferior vena cava patch

Shortage of supply of organs for donation means that every viable organ should be given the best chance possible for transplantation. As such, we present a method of renal vein reconstruction of a deceased donor kidney following injury during the organ recovery process.

Expansion of dysfunctional CD56-CD16+ NK cells in chronic hepatitis B patients

BACKGROUND & AIMS

Natural killer (NK) cells are primary innate effector cells that play an important role in the control of human viral infections. During chronic viral infection, NK cells undergo significant changes in phenotype, function and subset distribution, including the appearance of CD56-CD16+ (CD56-) NK cells, previously identified in chronic human immunodeficiency virus (HIV) and hepatitis C virus infection. However, the presence of CD56- NK cells in the pathogenesis of chronic hepatitis B (CHB) remains unknown.

METHODS

Phenotype and function of CD56- NK cells from patients with CHB (n = 28) were assessed using flow cytometry and in vitro stimulation with HBV antigen.

RESULTS

CHB patients had a higher frequency of CD56- NK cells compared to healthy controls in peripheral blood (6.2% vs 1.4%, P < .0001). Compared to CD56+ NK cells, CD56- NK cells had increased expression of inhibitory receptors, and reduced expression of activating receptors, as measured by MFI and qPCR. CD56- NK cells were less responsive to target cell and cytokine stimulation compared to their CD56+ counterparts. In addition, CD56- NK cells demonstrated defective dendritic cells (DCs) interactions resulting in reduced DCs maturation, lower expression of NK CD69 and impaired capacity of NK cells to eliminate immature DCs in co-culture studies. Finally, frequency of CD56- NK cells was positively correlated with serum HBV DNA levels.

CONCLUSION

Chronic HBV infection induces the expansion of highly dysfunctional of CD56- NK cells that likely contribute to inefficient innate and adaptive antiviral immune response in chronic HBV infection.

Successful Expectant Management of Nonocclusive Thrombosis in Simultaneous Pancreas-Kidney Transplantation

BACKGROUND

Simultaneous pancreas-kidney (SPK) transplantation can be complicated by thrombosis in the early post-transplant period.

METHODS

We performed a single-center retrospective study examining risk factors, management, and outcomes of modern era SPK transplants. We reviewed 235 recipients over 10 years (January 1, 2008, to September 1, 2017). We used multivariate analysis to examine donor, recipient, and operative risk factors for thrombosis.

RESULTS

Forty-one patients (17%) had a thrombosis diagnosed on postoperative imaging, but 61% of these patients (n = 25/41) did not lose their graft secondary to the thrombosis. Nine patients (22%) were managed with watchful waiting and serial imaging, 12 (29%) were managed with therapeutic anticoagulation, and 4 (10%) required laparotomy and graft thrombectomy. Sixteen of 235 pancreas grafts (6.8%) required pancreatectomy, and 10 of these cases occurred in the first half of the study, before 2012. The risk of thrombosis leading to graft loss increased 11.2-fold in recipients with a body mass index (calculated as weight in kilograms divided by height in meters squared) > 25 compared with others (odds ratio, 11.2; 95% CI, 1.1-116.7; P = .043).

CONCLUSIONS

The majority of SPK transplants (61%) complicated by thrombosis of the pancreatic graft were salvaged by use of imaging, anticoagulation, and in select cases, laparotomy and graft thrombectomy.

Day-only elective cholecystectomy: early experience and barriers to implementation in Australia

BACKGROUND

Day-only laparoscopic cholecystectomy (DOLC) has been shown to be safe and feasible yet has not been widely implemented in Australia. This study explores the introduction of routine DOLC to Westmead Hospital, and highlights the barriers to its implementation.

METHODS

Routine day-only cholecystectomy protocol was introduced at Westmead Hospital in 2014. A retrospective review of patients who underwent elective laparoscopic cholecystectomy during a 12-month period in 2014 was compared to a 12-month period in 2018, to examine the changes in practice after implementation of a unit protocol. Data were collected on patient demographics, admission category, outcomes and re-presentations.

RESULTS

A total of 282 patients were included in the study, of these 169 were booked as day procedures, with 124 (73%) successfully discharged on the same day. There was a significant increase in the proportion of patients booked as day-only from 2014 to 2018 (48% versus 73%, P < 0.001). Day-only failure rates (unplanned overnight admissions), readmissions and complication rates were comparable between the two periods. The most common reason for unplanned overnight admissions were due to intraoperative findings (n = 28/45).

CONCLUSION

Routine DOLC can be adopted in Australian hospitals without compromise to patient safety. Unplanned overnight admission is predominantly due to unexpected surgical pathology and can be reduced by protocols for the use of drains and planned outpatient endoscopic retrograde cholangiopancreatography. Unplanned outpatient review can be minimized by optimizing both intra- and post-operative pain management. Individual surgeon and anaesthetist preferences remain an obstacle to a standardized protocol in the Australian setting.

An aptamer-based drug delivery agent (CD133-apt-Dox) selectively and effectively kills liver cancer stem-like cells

Liver cancer has no effective therapies, hence a poor survival. Cancer stem-like cells not only contribute to cancer initiation and progression, but also to drug resistance, cancer metastasis, and eventually treatment failure. Hence, any approaches that can effectively kill cancer stem-like cells hold a great potential for cancer treatment. CD133 is a robust marker for liver cancer stem-like cells. We developed a specific aptamer against CD133 (CD133-apt), and then loaded this aptamer with an anticancer drug doxorubicin (CD133-apt-Dox). The efficacy of CD133-apt-Dox in targeting liver cancer stem-like cells and its overall effect in treating liver cancer were investigated using multiple in vitro and in vivo studies including in patients-derived liver cancer organoids. We have observed that CD133-apt could preferably delivered doxorubicin to CD133-expressing cells with efficient drug accumulation and retention. CD133-apt-Dox impaired the self-renewal capacity of liver cancer stem-like cells and attenuated their stem-ness phenotypes in vitro or in vivo. CD133-apt-Dox significantly inhibited the growth of liver cancer cells and patients-derived organoids and reduced the growth of xenograft tumours in nude mice inhibited the growth of DEN-induced liver cancer in immunocompetent mice. Hence, aptamer-mediated targeting of CD133 is a highly promising approach for liver cancer therapy.

Paediatric kidney transplants from donors aged 1 year and under: an analysis of the Australian and New Zealand Dialysis and Transplant Registry from 1963 to 2018

Kidneys from very small donors have the potential to significantly expand the donor pool. We describe the collective experience of transplantation using kidneys from donors aged ≤1 year in Australian and New Zealand. The ANZDATA registry was analysed on all deceased donor kidney transplants from donors aged ≤1 year. We compared recipient characteristics and outcomes between 1963-1999 and 2000-2018. From 1963 to 1999, 16 transplants were performed [9 (56%) adults, 7 (44%) children]. Death-censored graft survival was 50% and 43% at 1 and 5 years, respectively. Patient survival was 90% and 87% at 1 and 5 years, respectively. From 2000 to 2018, 26 transplants were performed [25 (96%) adults, 1 (4%) children]. Mean creatinine was 73 µmol/l ±49.1 at 5 years. Death-censored graft survival was 85% at 1 and 5 years. Patient survival was 100% at 1 and 5 years. Thrombosis was the cause of graft loss in 12% of recipients in the first era from 1963 to 1999, and 8% of recipients in the second era from 2000 to 2018. We advocate the judicious use of these small paediatric grafts from donors ≤1 year old. Optimal selection of donor and recipients may lead to greater acceptance and success of transplantation from very young donors.

How to do it: a robotic kidney autotransplant

We describe Australia's first reported case of robotic kidney autotransplantation for a complex renal artery aneurysm. It is potentially a safe, minimally invasive method of salvaging renal parenchyma and preservation of renal function in patients with complex renovascular conditions. This technique shows promise in carefully selected patients performed in centres with surgeons experienced in both kidney transplantation and the robotic platform.

Pharmacologic targeting of renal ischemia-reperfusion injury using a normothermic machine perfusion platform

Normothermic machine perfusion (NMP) is an emerging modality for kidney preservation prior to transplantation. NMP may allow directed pharmacomodulation of renal ischemia-reperfusion injury (IRI) without the need for systemic donor/recipient therapies. Three proven anti-IRI agents not in widespread clinical use, CD47-blocking antibody (αCD47Ab), soluble complement receptor 1 (sCR1), and recombinant thrombomodulin (rTM), were compared in a murine model of kidney IRI. The most effective agent was then utilized in a custom NMP circuit for the treatment of isolated porcine kidneys, ascertaining the impact of the drug on perfusion and IRI-related parameters. αCD47Ab conferred the greatest protection against IRI in mice after 24 hours. αCD47Ab was therefore chosen as the candidate agent for addition to the NMP circuit. CD47 receptor binding was demonstrated by immunofluorescence. Renal perfusion/flow improved with CD47 blockade, with a corresponding reduction in oxidative stress and histologic damage compared to untreated NMP kidneys. Tubular and glomerular functional parameters were not significantly impacted by αCD47Ab treatment during NMP. In a murine renal IRI model, αCD47Ab was confirmed as a superior anti-IRI agent compared to therapies targeting other pathways. NMP enabled effective, direct delivery of this drug to porcine kidneys, although further efficacy needs to be proven in the transplantation setting.

Survival outcomes of hepatic resections in Bismuth-Corlette type IV cholangiocarcinoma

BACKGROUND

Surgical resection for Bismuth-Corlette type IV (BC-IV) hilar cholangiocarcinomas, also termed Klatskin tumours are technically challenging and were once considered unresectable tumours. Following advances in hepatobiliary imaging and surgical techniques, emerging evidence suggests that surgical resection is a viable avenue for long-term survival. We aimed to identify factors affecting survival outcomes of hepatic resections for BC-IV cholangiocarcinomas.

METHOD

A systematic review was performed across multiple databases and several clinical trial registries. Two reviewers independently screened and selected papers that contained survival data on BC-IV cholangiocarcinoma after hepatic resections.

RESULTS

Of 13 499 papers from our search result, 21 papers satisfied the inclusion criteria. The median post-operative survival was 30.8 months. The average 1- and 5-year post-operative survivals were 61.6 and 33.3%, respectively. Predictors of long-term survival included achievement of R0 margins, minimisation of operative time and reduction intra-operative blood loss.

CONCLUSION

Our analysis demonstrates improving post-operative outcomes and survival in surgical resection of BC-IV cholangiocarcinoma and suggests that radical surgical resection is a valid treatment option for the disease.

Macrophage Coordination of the Interferon Lambda Immune Response

Lambda interferons (IFN-λs) are a major component of the innate immune defense to viruses, bacteria, and fungi. In human liver, IFN-λ not only drives antiviral responses, but also promotes inflammation and fibrosis in viral and non-viral diseases. Here we demonstrate that macrophages are primary responders to IFN-λ, uniquely positioned to bridge the gap between IFN-λ producing cells and lymphocyte populations that are not intrinsically responsive to IFN-λ. While CD14⁺ monocytes do not express the IFN-λ receptor, IFNLR1, sensitivity is quickly gained upon differentiation to macrophages in vitro. IFN-λ stimulates macrophage cytotoxicity and phagocytosis as well as the secretion of pro-inflammatory cytokines and interferon stimulated genes that mediate immune cell chemotaxis and effector functions. In particular, IFN-λ induced CCR5 and CXCR3 chemokines, stimulating T and NK cell migration, as well as subsequent NK cell cytotoxicity. Using immunofluorescence and cell sorting techniques, we confirmed that human liver macrophages expressing CD14 and CD68 are highly responsive to IFN-λ ex vivo. Together, these data highlight a novel role for macrophages in shaping IFN-λ dependent immune responses both directly through pro-inflammatory activity and indirectly by recruiting and activating IFN-λ unresponsive lymphocytes.

Intraoperative detection of aberrant biliary anatomy via intraoperative cholangiography during laparoscopic cholecystectomy

BACKGROUND

Laparoscopic cholecystectomy (LC) is the standard of treatment for symptomatic cholelithiasis. Although intraoperative cholangiography (IOC) is widely used as an adjunct to LC, there is still no worldwide consensus on the value of its routine use. Anatomical studies have shown that variations of the biliary tree are present in approximately 35% of patients with variations in right hepatic second-order ducts being especially common (15-20%). Approximately, 70-80% of all iatrogenic bile duct injuries are a consequence of misidentification of biliary anatomy. The purpose of this study was to assess the adequacy of and the reporting of IOCs during LC.

METHODS

IOCs obtained from 300 consecutive LCs between July 2014 and July 2016 were analysed retrospectively by two surgical trainees and confirmed by a radiologist. Biliary tree anatomy was classified from IOC films as described by Couinaud (1957) and correlated with documented findings. The accuracy of intraoperative reporting was assessed. Biliary anatomy was correlated to clinical outcome.

RESULTS

A total of 95% of IOCs adequately demonstrated biliary anatomy. Aberrant right sectoral ducts were identified in 15.2% of the complete IOCs, and 2.6% demonstrated left sectoral or confluence anomalies. Only 20.4% of these were reported intraoperatively. Bile leaks occurred in two patients who had IOCs (0.73%) and two who did not (7.4%).

CONCLUSION

Surgeons generally demonstrate biliary anatomy well on IOC but reporting of sectoral duct variation can be improved. Further research is needed to determine whether anatomical variation is related to ductal injury.

Aortic Versus Dual Perfusion for Retrieval of the Liver After Brain Death: A National Registry Analysis

There is lack of consensus in the literature regarding the comparative efficacy of in situ aortic-only compared with dual (aortic and portal venous) perfusion for retrieval and transplantation of the liver. Recipient outcomes from the Australia/New Zealand Liver Transplant Registry (2007-2016), including patient and graft survival and causes of graft loss, were stratified by perfusion route. Subgroup analyses were conducted for higher-risk donors. A total of 1382 liver transplantation recipients were analyzed (957 aortic-only; 425 dual perfusion). There were no significant differences in 5-year graft and patient survivals between the aortic-only and dual cohorts (80.1% versus 84.6% and 82.6% versus 87.8%, respectively) or in the odds ratios of primary nonfunction, thrombotic graft loss, or graft loss secondary to biliary complications or acute rejection. When analyzing only higher-risk donors (n = 369), multivariate graft survival was significantly less in the aortic-only cohort (hazard ratio, 0.49; 95% confidence interval, 0.26-0.92). Overall, there was a trend toward improved outcomes when dual perfusion was used, which became significant when considering higher-risk donors alone. Inferences into the ideal perfusion technique in multiorgan procurement will require further investigation by way of a randomized controlled trial, and outcomes after the transplantation of other organs will also need to be considered.

Molecular and clinical characterization of citrin deficiency in a cohort of Chinese patients in Hong Kong

Background and objectives: This retrospective study analysed a case series of subjects with citrin deficiency, and aims to present the molecular and clinical characterization of this disease in the Hong Kong Chinese population for the first time. Patients and Methods: Data from medical records of eighteen patients with citrin deficiency (years 2006–2015) were retrieved. Demographic data, biochemical parameters, radiological results, genetic testing results, management, and clinical outcome were collected and analysed. Results: Eighteen patients with diagnosis of citrin deficiency were recruited. All 18 patients carried at least one common pathogenic variant c.852_855delTATG in SLC25A13. Prolonged jaundice (neonatal intrahepatic cholestasis caused by citrin deficiency, NICCD) was the most common presenting symptom, in conjunction with elevated plasma citrulline, threonine, alkaline phosphatase, and alpha-fetoprotein levels. The abnormal biochemical parameters including liver derangement returned to normal range in most of the cases by 6 months of age after the introduction of a lactose-free formula. There were a few cases with atypical presentations. Two subjects did not present with NICCD, and were subsequently diagnosed later in life after their siblings presented with symptoms of citrin deficiency at one month of age and subsequently received a molecular diagnosis. One patient with citrin deficiency also exhibited multiple liver hemangioendotheliomas, which subsided gradually after introduction of a lactose-free formula. Only one patient from this cohort was offered expanded metabolic screening at birth. She was not ascertained by conducted newborn screening and was diagnosed upon presentation with cholestatic jaundice by 1 month of age. Conclusion: This is the first report of the clinical and molecular characterization of a large cohort of patients with citrin deficiency in Hong Kong. The presentation of this cohort of patients expands the clinical phenotypic spectrum of NICCD. Benign liver tumors such as hemangioendotheliomas may be associated with citrin deficiency in addition to the well-known association with hepatocellular carcinoma. Citrin deficiency may manifest in later infancy period with an NICCD-like phenotype. Furthermore, this condition is not always ascertained by expanded newborn metabolic screening testing.

HBeAg levels at week 24 predict response to 8 years of tenofovir in HBeAg-positive chronic hepatitis B patients

BACKGROUND

Hepatitis B e antigen (HBeAg) seroconversion is a treatment endpoint for HBeAg-positive CHB, and a necessary precursor to HBsAg loss. Biomarkers that predict serological outcomes would be useful.

AIM

To evaluate the utility of measuring HBeAg levels for predicting HBeAg seroconversion and HBsAg loss under long-term tenofovir (TDF) therapy.

METHODS

A total of 266 patients were enrolled into a phase III study of TDF vs adefovir (ADV) for 48 weeks in HBeAg-positive patients, followed by open-label TDF up to 384 weeks. Serum HBeAg levels were measured for subjects with samples available at both baseline and week 24 of treatment (n = 200). Analysis compared subjects who achieved HBeAg seroconversion by week 384 vs no HBeAg seroconversion.

RESULTS

HBeAg seroconversion rate was 52% by week 384. Time to HBeAg seroconversion was 80 weeks (IQR: 36-162). HBeAg decline at week 24 was associated with HBeAg seroconversion (1.63 vs 0.90 log₁₀ PEIU/mL, P = .002). The optimal threshold for identifying HBeAg seroconversion was HBeAg decline ≥2.2 log₁₀ PEIU/mL at week 24, with HBeAg seroconversion achieved by 76% of patients, compared to 44% if HBeAg decline <2.2 log₁₀ (P < .0001). HBeAg decline ≥2.2 log₁₀ PEIU/mL at week 24 was associated with HBsAg loss in genotype A or D patients (38% vs 15%, P = .03). Precore/basal core promotor variants were associated with lower baseline HBeAg levels, but not HBeAg seroconversion.

CONCLUSION

Decline in HBeAg levels by week 24 was associated with HBeAg seroconversion and HBsAg loss in HBeAg-positive chronic hepatitis B patients treated with long-term TDF.

Extra-corporeal normothermic machine perfusion of the porcine kidney: working towards future utilization in Australasia

BACKGROUND

The ongoing supply-demand gap with respect to donor kidneys for transplantation necessitates the increased use of higher kidney donor profile index and/or donation after circulatory death (DCD) kidneys. Machine perfusion (MP) preservation has become increasingly popular as a means to preserve such organs. Human data regarding normothermic kidney MP (NMP) is in its infancy, and such a system has not been established in the Australasian clinical setting.

METHODS

Modified cardio-pulmonary bypass technology was utilized to develop a viable NMP kidney perfusion system using a porcine DCD model. System development and optimization occurred in two stages, with system components added in each experiment to identify optimal perfusion conditions.

RESULTS

Device functionality was demonstrated by the successful perfusion of and urine production by, eight porcine kidneys. Urine production diminished in the presence of colloid in the perfusate. Pressure-controlled (compared with flow-controlled) perfusion is preferable as a safe perfusion pressure range can be maintained. More physiologic perfusion conditions are achieved if oxygenation is provided by an oxygen/carbon dioxide mixture compared to 100% oxygen.

CONCLUSION

A viable and reproducible NMP system was established and tested in porcine kidneys, which was able to simulate graft function extra-corporeally. Further work is required to identify the most optimal perfusion conditions. Prior to its utilization in clinical transplantation, the system should be tested in non-transplanted human kidneys.

In Vivo Plasminogen Deficiency Reduces Fat Accumulation

Obesity and non-insulin dependent diabetes are associated with a decrease in fibrinolysis, which is mediated by the plasminogen system. The purpose of the current study was to investigate the role of the plasminogen system in the reduced body weight of the plasminogen deficient (Plg−/−) mice. In this study we have found that the reduced body weight in Plg−/− mice is due to a reduced rate of the adipose tissue (25% less) and whole body fat (30% less) accumulation during growth in Plg−/− compared to wild-type (WT) littermates. When the mice are fed a high fat-lipogenic diet, adipose tissue accumulation increases in the Plg−/− mice indicating that the capacity for lipid filling of cells was not blocked. In addition, glycerol phosphate dehydrogenase, a marker of late differentiation, was not different in the depots from WT and Plg−/− mice. The number of stromal cells (number × 105/g adipose tissue), isolated from inguinal (Plg−/− 3.4 ± 1.2, n = 6; WT 0.17 ± 0.07, n = 7, p < 0.02) and gonadal (Plg−/− 11.0 ± 0.4, n = 6; WT 3.1 ± 0.7, n = 7, p < 0.05) fat depots, was markedly higher in the depots from the Plg−/− mice than WT mice. Differentiation of stromal cells in culture from the Plg−/− mice was reduced compared to cells from WT mice. These results suggest that differences in the stromal cell population are responsible for the reduced adipose tissue accumulation in the Plg−/− mice, and that the plasminogen system plays an important role in adipose tissue accumulation.

Imaging modalities in the diagnosis of pancreatic adenocarcinoma: A systematic review and meta-analysis of sensitivity, specificity and diagnostic accuracy

BACKGROUND

Pancreatic cancer, primarily pancreatic ductal adenocarcinoma (PDAC), accounts for 2.4% of cancer diagnoses and 5.8% of cancer death annually. Early diagnoses can improve 5-year survival in PDAC. The aim of this systematic review was to determine the sensitivity, specificity and diagnostic accuracy values for MRI, CT, PET&PET/CT, EUS and transabdominal ultrasound (TAUS) in the diagnosis of PDAC.

METHODS

A systematic review was undertaken to identify studies reporting sensitivity, specificity and/or diagnostic accuracy for the diagnosis of PDAC with MRI, CT, PET, EUS or TAUS. Proportional meta-analysis was performed for each modality.

RESULTS

A total of 5399 patients, 3567 with PDAC, from 52 studies were included. The sensitivity, specificity and diagnostic accuracy were 93% (95% CI=88-96), 89% (95% CI=82-94) and 90% (95% CI=86-94) for MRI; 90% (95% CI=87-93), 87% (95% CI=79-93) and 89% (95% CI=85-93) for CT; 89% (95% CI=85-93), 70% (95% CI=54-84) and 84% (95% CI=79-89) for PET; 91% (95% CI=87-94), 86% (95% CI=81-91) and 89% (95% CI=87-92) for EUS; and 88% (95% CI=86-90), 94% (95% CI=87-98) and 91% (95% C=87-93) for TAUS.

CONCLUSION

This review concludes all modalities, except for PET, are equivalent within 95% confidence intervals for the diagnosis of PDAC.

Dual kidney transplant techniques: A systematic review

BACKGROUND

Dual kidney transplantation (DKT) was developed to improve outcomes from transplantation of extended criteria donors (ECD). This study examined which surgical techniques have been reported for DKT and whether any technique had superior patient and graft survival.

METHOD

Electronic databases were searched for published studies mapping to MESH terms: "kidney or renal" AND "transplan*" AND "dual or double." Single case reports, studies of patients less than 18 years old, studies which did not describe the surgical technique, and studies that did not report patient or graft survival were excluded.

RESULTS

Fifteen reports of 434 DKT recipients were identified. Three techniques were described: bilateral placement; unilateral placement with separate anastomoses; and unilateral placement with patch anastomoses. Patient survival across all three techniques was over 95% at 1 year, and graft survival was also similar at over 90%. Rates of delayed graft function were between 20% and 30% across all techniques.

CONCLUSION

The three techniques have equivalent delayed graft function as well as patient and graft survival rates. This is an encouraging result as it means that the surgeon can choose to use the technique which is most appropriate for their own skills and for the patient.

Laparoscopic partial cholecystectomy: A way of getting out of trouble

Aims: Laparoscopic cholecystectomy (LC) is currently the standard treatment for symptomatic gallstones. In the presence of moderate to severe inflammation when dissection of the cholecystohepatic triangle cannot be safely achieved, laparoscopic partial cholecystectomy (LPC) has been proposed as an alternative to open conversion to prevent bile duct injuries. The aim of this study is to review our experience of the technique. Materials and Methods: A retrospective review of all patients who underwent laparoscopic cholecystectomy under the upper gastrointestinal surgical unit at Westmead Hospital was undertaken. The study included all emergency and elective cases during a period from February 2012 to February 2014. Demographic, clinical, operative and postoperative characteristics including operative technique, placement of a drain, complications, length of hospital stay and histopathology were collected. Results: A total of 404 patients underwent LC during the two year study period of which 23 were LPC's. Patients who underwent LPC tended to be older and more likely of the male gender. These patients were also more likely to be an emergency operation and have a higher ASA grade compared to the LC group. Length of stay and operative time tended to be longer. There were five (22%) bile leaks postoperatively and all were successfully managed with postoperative ERCP and stenting. The major complication rate was 35% (8/23) with no bile duct injury or perioperative mortality. Conclusion: This current case series adds further evidence to suggest that LPC is a viable alternative to conversion in cases of difficult LC.

Percutaneous vs. endoscopic pre-operative biliary drainage in hilar cholangiocarcinoma - a systematic review and meta-analysis

BACKGROUND

The strategy for preoperative management of biliary obstruction in hilar cholangiocarcinoma (HCCA) patients with regards to drainage by endoscopic (EBD) or percutaneous (PTBD) methods is not clearly defined. The aim of this study was to investigate the utility, complications and therapeutic efficacy of these methods in HCCA patients, with a secondary aim to assess the use of portal vein embolization (PVE) in patients undergoing drainage.

METHODS

Studies incorporating HCCA patients undergoing biliary drainage prior to curative resection were included (EMBASE and Medline databases). Analyses included baseline drainage data, procedure-related complications and efficacy, post-operative parameters, and meta-analyses where applicable.

RESULTS

Fifteen studies were included, with EBD performed in 536 patients (52%). Unilateral drainage of the future liver remnant was undertaken in 94% of patients. There was a trend towards higher procedure conversion (RR 7.36, p = 0.07) and cholangitis (RR 3.36, p = 0.15) rates in the EBD group. Where specified, 134 (30%) drained patients had PVE, in association with a major hepatectomy in 131 patients (98%). Post-operative hepatic failure occurred in 22 (11%) of EBD patients compared to 56 (13%) of PTBD patients, whilst median 1-year survival in these groups was 91% and 73%, respectively.

DISCUSSION

The accepted practice is for most jaundiced HCCA patients to have preoperative drainage of the future liver remnant. EBD may be associated with more immediate procedure-related complications, although it is certainly not inferior compared to PTBD in the long term.

Short duration of lamivudine for the prevention of hepatitis B virus transmission in pregnancy: lack of potency and selection of resistance mutations

This study sought to assess the antiviral efficacy of lamivudine (LMV) administered during third trimester to reduce maternal viraemia and to identify the emergence of LMV resistance. A prospective observational analysis was performed on 26 mothers with high viral load (>10⁷ IU/mL). Twenty-one women received LMV (treated group) for an average of 53 days (range 22-88 days), and the remaining five formed the untreated control group. Serum samples from two time points were used to measure HBV DNA levels and antiviral drug resistance. The LMV-treated women achieved a median HBV DNA reduction of 2.6-log10 IU/mL. Although end-of-treatment (EOT) HBV DNA in four (18%) LMV-treated women remained at >10(7) IU/mL (± 0.5 log IU/mL), no mother-to-baby transmission was observed. In contrast, a baby from the untreated mother was HBsAg positive at 9 months postpartum. Four technologies were used for drug resistance testing. Only ultra-deep pyrosequencing (UDPS) was sufficiently sensitive to detect minor viral variants down to <1%. UDPS showed that LMV therapy resulted in increased viral quasispecies diversity and positive selection of HBV variants with reverse transcriptase amino acid substitutions at sites associated with primary LMV resistance (rtM204I/V and rtA181T) in four (19%) women. These viral variants were detected mostly at low frequencies (0.63-5.92%) at EOT, but one LMV-treated mother had an rtA181T variant that increased from 2.2% pretherapy to 25.59% at EOT. This mother was also infected with the vaccine escape variant (sG145R), which was inhibited by LMV treatment. LMV therapy during late pregnancy only reduced maternal viraemia moderately, and drug-resistant viral variants emerged.

Molecular virology of hepatitis B virus, sub-genotype C4 in northern Australian Indigenous populations

Indigenous Australians experience a significant health burden from chronic hepatitis B infection; however, the strain of hepatitis B virus (HBV) found among Indigenous Australians has not been well characterized. Blood samples were collected from 65 Indigenous Australians with chronic HBV infection from across the Top End of Australia's Northern Territory. Phylogenetic analysis of HBV from these samples revealed that 100% of the isolates were genotype C, sub-genotype C4, expressing the serotype ayw3. This strain is a divergent group within the HBV/C genotype, and has only been described in Indigenous Australians. Evidence of recombination was suggested by discordant phylogenetic clustering of the C4 sequences when comparing the full genome to the surface region and confirmed by recombination analysis which showed the surface gene region to be most closely related to genotype J, while the remaining regions of the genome were most similar to genotype C sequences. Mutational analysis revealed the presence of multiple mutations that have been linked with more rapid liver disease progression and an increased risk of hepatocellular carcinoma. These mutations were detected in the majority of sequences examined. Variants associated with vaccine failure were detected as the predominant viral quasi-species in 3/35 samples. In summary, the HBV C4 variant found in this population has a high potential to cause advanced liver disease and to escape vaccination programs. Further in vitro functional and natural history studies are warranted in order to determine the clinical and public health consequences of infection with the HBV C4 variant in these communities.

High frequency of lamivudine resistance mutations in Brazilian patients co-infected with HIV and hepatitis B

This study analyzed the genotype distribution and frequency of lamivudine (LAM) and tenofovir (TDF) resistance mutations in a group of patients co-infected with HIV and hepatitis B virus (HBV). A cross-sectional study of 847 patients with HIV was conducted. Patients provided blood samples for HBsAg detection. The load of HBV was determined using an "in-house" real-time polymerase chain reaction. HBV genotypes/subgenotypes, antiviral resistance, basal core promoter (BCP), and precore mutations were detected by DNA sequencing. Twenty-eight patients with co-infection were identified. The distribution of HBV genotypes among these patients was A (n = 9; 50%), D (n = 4; 22.2%), G (n = 3; 16.7%), and F (n = 2; 11.1%). Eighteen patients were treated with LAM and six patients were treated with LAM plus TDF. The length of exposure to LAM and TDF varied from 4 to 216 months. LAM resistance substitutions (rtL180M + rtM204V) were detected in 10 (50%) of the 20 patients with viremia. This pattern and an accompanying rtV173L mutation was found in four patients. Three patients with the triple polymerase substitution pattern (rtV173L + rtL180M + rtM204V) had associated changes in the envelope gene (sE164D + sI195M). Mutations in the BCP region (A1762T, G1764A) and in the precore region (G1896A, G1899A) were also found. No putative TDF resistance substitution was detected. The data suggest that prolonged LAM use is associated with the emergence of particular changes in the HBV genome, including substitutions that may elicit a vaccine escape phenotype. No putative TDF resistance change was detected after prolonged use of TDF.

Effect of hyaluronidase on ocular motility and eyelid function in sub-Tenon's anaesthesia: randomised controlled trial

PURPOSE

To assess the effect of hyaluronidase on eye and eyelid movements when used as an adjunct in sub-Tenon's anaesthesia.

METHODS

A total of 60 patients who had sub-Tenon's anaesthesia prior to phacoemulsification surgery were divided into two equal groups in a double-masked randomised controlled fashion. Of these, Group A had 4 ml lignocaine 2%, while Group B had 4 ml lignocaine 2% with the addition of sodium hyaluronidase 75 IU/ml. Ocular motility, levator, and orbicularis oculi function were measured in all patients at 5 and 8 min. Levator function was scored from 0 (no function) to 3 (complete function) while orbicularis function was scored from 0 to 2. The score for ocular motility was the sum in four positions of gaze, each position scoring from 0 to 2. Results were compared using a nonparametric test.

RESULTS

Group B achieved significantly better ocular and lid akinesia than Group A both at 5 and 8 min with P<0.01. The median scores for levator function at 5 and 8 min were 2 for Group A and 0 for Group B. For orbicularis function, the median scores at both time intervals were 2 for Group A and 1 for Group B. For ocular motility, the median score for Group A at 5 min was 3 and at 8 min was 2.5; for Group B at 5 min was 0.5 and at 8 min was 0.

CONCLUSIONS

The addition of hyaluronidase in sub-Tenon's anaesthesia has a significant effect in improving ocular and lid (levator and orbicularis) akinesia.

Chronic hepatitis B: recommendations for therapy based on the natural history of disease in Australian patients

BACKGROUND

Chronic hepatitis B infection (CHB) is a major health problem in Australia and worldwide. CHB is associated with significant long-term morbidity and mortality. Well tolerated treatment is now available, however the development of resistance is common and the optimal timing of treatment is yet to be determined. Identifying the factors that influence the natural history of CHB may help determine which patients need treatment and when to start it.

OBJECTIVE

To determine the demographics, clinical features and virological profile of Australian patients infected with CHB and the influence of these factors on disease activity and severity.

STUDY DESIGN

Review of prospectively collected demographic, clinical and virological features of all patients positive for hepatitis B surface antigen (HBsAg) for more than 6 months who were referred to St. Vincent's Hospital liver clinics. Age, sex and ethnicity were correlated with hepatitis B e antigen status (HBeAg), HBV replication status (ALT and HBV DNA), genotype and liver histology.

RESULTS

703 chronic hepatitis B surface antigen positive patients were identified. The patients were predominantly male with an average age of 44. Eighty two percent of patients were born overseas, primarily from Asian (65%) and Mediterranean countries (14%). Two thirds (426) had an elevated ALT (median 79) at presentation. HBeAg was positive in 37%. Active viral replication, defined as abnormal ALT or positive HBVDNA, was present in 74%, 48% of whom were HBeAg negative. In a subset of 103 patients genotyped, 8% had genotype A, 29% B, 41% C and 22% D. Genotype correlated with ethnicity; patients infected with genotypes A were predominantly Caucasian, B and C were Asian, and D were Mediterranean. Of 296 (42%) patients who underwent liver biopsy, 76 (27%) had advanced fibrosis. Advanced fibrosis was associated with increasing age and Mediterranean ethnicity.

CONCLUSION AND RECOMMENDATIONS

Perinatal or early childhood transmission is predominant mode of infection in Australia. Two thirds of this cohort had active replication and were at increased risk of developing cirrhosis and/or hepatoma. Advanced disease was associated with age and ethnicity. HBeAg negative CHB accounts for almost half of all those with active viral replication. This parallels the rise in this form of CHB in Asia and the Mediterranean basin. Screening should be offered to people born in, or with parents born in areas of high endemnicity. To detect the development of active disease, patients with positive HBsAg but normal ALT should have liver function tests done 6 monthly and those with elevated ALT should be referred for consideration of therapy, irrespective of HBeAg status.

Microfracture and changes in energy absorption to fracture of young vertebral cancellous bone following physiological fatigue loading

STUDY DESIGN

Fifty-five human thoracolumbar vertebrae were randomly fatigue loaded and analyzed.

OBJECTIVES

The purpose of this study was to explore the relationship between fatigue loading, trabecular microfracture, and energy absorption to fracture in human cadaveric thoracolumbar vertebrae.

BACKGROUND

Although trabecular microfractures are found in vivo and have been produced by fatigue loading in vitro, the effect of the level of physiologic fatigue loading on microfracture and energy absorption has not been investigated.

METHODS

Fifty-five human thoracolumbar vertebrae (T11-L4) were randomly divided into 5 groups: 1) control (no loading, n = 6); 2) axial compression to yield (n = 7); and 3-5) 20,000 cycles of fatigue loading at 2 Hz (each n = 14). The level of fatigue loading was determined as a proportion of the yield load of Group 2 as follows: 10% (Group 3), 20% (Group 4), and 30% (Group 5). Half of the specimens in groups 3 to 5 were used for radiographic and histomorphometric analysis to determine microfracture density and distribution, whereas the other half were tested to determine the energy absorption to yield failure.

RESULTS

No radiographic evidence of gross fracture was found in any of the groups following fatigue loading. A mean 7.5% increase in stiffness was found in specimens subject to cyclic loading at 10% of yield stress (Group 3). Fatigue at 20% (Group 4) and 30% of yield stress (Group 5) caused significantly higher (P < 0.05) increases in mean stiffness of 23.6% and 24.2%, respectively. Microfracture density increased from 0.46/mm in Group 3 to 0.66/mm in Group 4 and 0.94/mm in Group 5 (P < 0.05). The energy absorbed to failure decreased from 21.9 J in Group 3 to 18.1 J and 19.6 J in Groups 4 and 5, respectively (P < 0.05).

CONCLUSIONS

Fatigue loading at physiologic levels produced microfractures that are not detectable by radiography. Increased fatigue load results in an increase in microfracture density and decrease energy absorbed to fracture, indicating a reduced resistance to further fatigue loading.

In vivo plasminogen deficiency reduces fat accumulation

Obesity and non-insulin dependent diabetes are associated with a decrease in fibrinolysis, which is mediated by the plasminogen system. The purpose of the current study was to investigate the role of the plasminogen system in the reduced body weight of the plasminogen deficient (Plg-/-) mice. In this study we have found that the reduced body weight in Plg-/- mice is due to a reduced rate of the adipose tissue (25% less) and whole body fat (30% less) accumulation during growth in Plg-/- compared to wild-type (WT) littermates. When the mice are fed a high fat-lipogenic diet, adipose tissue accumulation increases in the Plg-/- mice indicating that the capacity for lipid filling of cells was not blocked. In addition, glycerol phosphate dehydrogenase, a marker of late differentiation, was not different in the depots from WT and Plg-/- mice. The number of stromal cells (number x 10(5)/g adipose tissue), isolated from inguinal (Plg-/- 3.4 +/- 1.2. n = 6; WT 0.17 +/- 0.07, n = 7, p < 0.02) and gonadal (Plg-/- 11.0 +/- 0.4, n = 6; WT 3.1 +/- 0.7, n = 7, p < 0.05) fat depots. was markedly higher in the depots from the Plg-/- mice than WT mice. Differentiation of stromal cells in culture from the Plg-/- mice was reduced compared to cells from WT mice. These results suggest that differences in the stromal cell population are responsible for the reduced adipose tissue accumulation in the Plg-/- mice, and that the plasminogen system plays an important role in adipose tissue accumulation.

Plasminogen binding is increased with adipocyte differentiation

The purpose of this study was to examine the role of the plasminogen system in the development of adipose tissue. Plasminogen binding capacity was determined in differentiated and undifferentiated cells from adipose tissue of plasminogen deficient mice and 3T3 cells, a well-characterized tissue culture model. In 3T3 cells, plasminogen binding was fivefold higher in differentiated cells compared to the undifferentiated cells. Inhibition of binding by carboxyl-terminal lysine analogs was similar for the differentiated and undifferentiated cells with tranexamic acid > EACA > lysine. The binding of plasminogen was concentration-dependent and approaches saturation in the both cell types. The number of plasminogen binding sites was tenfold higher in the differentiated compared to the undifferentiated cells. In isolated mature fat cells and stromal cell cultures from mouse adipose tissue, plasminogen binding was also higher in the differentiated mature fat cells and differentiated stromal cells compared to undifferentiated stromal cells. Plasminogen binding was elevated in the differentiated cells from the Plg-/- mice compared to cells from the WT mice. These results suggest that the plasminogen system plays an important role in adipose tissue development.

High level excretion of Norwalk-like virus following resolution of clinical illness

We report the case of an elderly woman excreting high levels (about 5 x 10(5) virions per gram of faeces) of Norwalk-like virus (NLV) in the absence of any clinical symptoms of gastroenteritis. Analysis by reverse transcription, polymerase chain reaction and DNA sequencing was carried out on a 342-nucleotide region of open reading frame 1. This indicated that the NLV belonged to genogroup 2 and was more closely related to the Camberwell subgroup, the most common circulating in southeast Australia at present, than to the Norwalk and Mexico viruses.

Primary sarcoma of the ribs in a large, mixed breed dog

A 9-year-old, 30-kg, neutered male, mixed breed dog was referred for en bloc resection of a tentatively diagnosed costal chondrosarcoma. Light microscopic examination of the excised mass confirmed osteosarcoma. Adjuvant chemotherapy with 4 treatments with carboplatin was initiated. There have been no signs of metastases 5 months postsurgery.