Comparable outcomes in donation after cardiac death and donation after brainstem death: a matched analysis of renal transplants.

Donation after cardiac death (DCD) donors provide a valuable source of grafts for renal transplantation. They are exposed to an initial warm ischemic insult, which can affect early function. We sought to compare our initial DCD experience in renal transplantation with a case-matched donation after brain death (DBD) cohort from the same period. We included all DCD transplantations in the first 5 years of the program. A control DBD group was matched with a variety of donor and recipient factors. We demonstrated a significantly increased early dysfunction (DGF and primary nonfunction). DCD graft function was poorer than the DBD equivalent at 1- and 3-years. However, medium-term recipient and graft outcomes were comparable. DCD grafts continue to play a vital role in renal transplantation despite evidence of early graft dysfunction.

Predicting donor asystole following withdrawal of treatment in donation after cardiac death.

Donation after cardiac death donation allows donor pool expansion. The period between withdrawal of treatment and donor a systole is extremely variable; its prolongation often results in unsuccessful organ procurement. We sought to assess a variety of donor variables to determine whether they predicted successful organ retrieval. We included all Donation after Cardiac Death (DCD) retrievals between 2002 and 2009, which were grouped as successful (n = 104) versus unsuccessful (n = 42). Factors that predicted unsuccessful organ procurement included older donor age, donor history of hypertension, higher at withdrawal, and absence of inotropic support. On multivariate analysis, mean arterial pressure retained its significance. Prediction of withdrawal-to-asystole time is complex, but our analysis suggested that donor blood pressure at withdrawal is an important predictor of whether retrieval would be successful.

Impact of cold ischemia on renal transplant outcomes following donation after cardiac death.

Donation after cardiac death (DCD) provides grafts in renal transplantation but is associated with increased early graft dysfunction. Cold ischemia time (CIT) is a factor that is thought to affect outcomes in renal transplantation. We sought to assess the impact of the length of CIT among our DCD cohort of renal transplants performed between April 2002 and December 2009. Since the median CIT was 15.5 hours, we formed two groups CIT < 15.5 (n = 100) and CIT > 15.5 hr (n = 98). We demonstrated an increased incidence of DGF among the extended CIT group, but the long outcomes and the mean graft function were otherwise comparable. In conclusion, CIT affects early graft function; every effort should be made to minimize it in renal transplantation using DCD kidneys.

Impact of age matching of donors to recipients on renal transplant outcomes following donation after cardiac death.

Organ donation after cardiac death (DCD) provides a valuable supply of grafts for renal transplantation. Age matching of donors to recipients is often used. We sought to determine the impact of age matching on the outcomes among our cohort of DCD renal transplant recipients. Using our institutional database, we gathered information on all DCD renal transplants performed between April 2002 and December 2009. We divided the cohort into two groups based upon the donor:recipient age ratio: age-matched (between 25th and 75th percentiles, n = 99) and non-age-matched (<25th percentile and >75th centile, n = 100). We failed to demonstrate any significant difference between the two groups in terms of early complications or long-term outcome or function. Age matching did not appear to affect graft outcomes, particularly for young donors, but may have a role in older donors.

Sequential transplant of paired kidneys following donation after cardiac death: impact of longer cold ischemia time on the second kidney on graft and patient outcome.

The United Kingdom has no national sharing scheme for kidneys received from donation after cardiac death (DCD). Therefore, both kidneys retrieved by a transplant team are implanted at a single unit, often sequentially. This study analyzes the impact of a prolonged cold ischaemia time on the second transplanted kidney and the effects on short-term and long-term outcomes in all our DCD renal implants from 2002 to 2009. Cold ischaemia time was significantly longer with the second kidney (P = .04) as was delayed graft function (P = .02). Acute rejection was increased in the first transplanted kidney (P < .001). Five-year patient survival was comparable between groups, but 5-year graft survival was higher in the second transplanted group (P = .04). The results confirm that, provided recipient centers are willing to accept higher initial rates of delayed graft function, it is acceptable to transplant DCD grafts sequentially without jeopardizing long-term graft or recipient outcome.

Outcomes following renal transplantation after multiorgan retrieval versus kidney-only retrieval in donation after cardiac death donors.

With the increase of donation after cardiac death (DCD) now including procurements for not only kidney but also liver, pancreas, and lung transplantations, we analyze whether multiorgan DCD retrievals have a negative impact on immediate and short-term renal transplant outcomes due to increased length of time of explantation of the kidney from the donor and the associated risks of re-warming. We performed a retrospective study of all DCD donors from 2002 to 2009 at a single unit. Immediate and short-term outcomes between kidney-only versus multiorgan retrieval were compared. Cold ischaemia was significant between the two groups (P = .04), but all other variables were nonsignificant. The results show that immediate graft function, rates of acute rejection and graft/recipient survival are comparable when DCD allografts are procured from both multiorgan and kidney-only donors. The comparable outcomes from kidney-only and multiorgan donations in this study may be due to by the highly selective use of donors for multiorgan DCD donation. This selectivity may explain the "better" quality of kidney for these cases in which patients were able to tolerate potentially injurious rewarming.

Renal transplantation following donation after cardiac death: impact of duration from withdrawal to asystole.

Donation after cardiac death (DCD) allows for expansion of the donor pool, however, the process for DCD donation can lead to a donor's physiological instability before asystole. This may have a detrimental effect on graft and patient outcomes. We analyzed all 201 DCD donations at our unit from 2002 to 2009 and compared short versus long durations to asystole around the median time (20 min). Delayed graft function was comparable between the groups (P = .13), primary nonfunction was increased in the long duration to asystole group (P < .0001), and acute rejection was increased in the short duration group (P < .001). Five year patient survival was comparable (P = .6). In conclusion, long duration asystole may have an immediate effect on graft survival, but it has no overall detrimental effect on longer-term outcomes. Further studies are required to investigate the acceptable time to wait from withdrawal to asystole.

Transplantation of adult-sized kidneys in low-weight pediatric recipients achieves short-term outcomes comparable to size-matched grafts.

Low-weight pediatric recipients are disadvantaged by scarcity of size-matched donors. ASK have been successfully used for pediatric recipients. We report the results of renal transplantation using ASK in low-weight pediatric recipients and compare outcomes in weight-matched and unmatched donor-recipient pairs. The outcomes of renal transplants using ASK grafts in low-weight (<20 kg) recipients from a single center over a 10-yr period were reviewed. Two groups, comprising recipients of grafts from weight-matched and mismatched donors, were compared. Primary outcome was one-yr graft survival. Secondary outcomes were one- and two-yr calculated eGFR, changes in recipient body weight, perioperative cardiovascular stability, rates of AR and DGF. Twenty-three low-weight recipients were transplanted. Eleven received ASK grafts from high-weight donors and 12 grafts from low-weight donors. One patient in each group had early graft loss. No significant difference was observed in rates of DGF, AR, one-yr graft or patient survival and perioperative cardiovascular parameters. ASK with considerable donor:recipient weight discrepancies can be safely transplanted into small pediatric recipients with comparable outcomes to grafts with less weight discrepancy.

Minimally invasive, video-assisted thyroidectomy: first experience from the United Kingdom.

INTRODUCTION: Minimally-invasive, video-assisted thyroidectomy (MIVAT) was developed to reduce scarring/trauma associated with cervical incisions used in open thyroidectomy. Results from various centres have been published internationally but none from the UK. This study reports the first results from the UK and compares them with other centres. We also aim to compare the results of a single-surgeon experience in a small/moderately-sized hospital to those of larger tertiary centres. PATIENTS AND METHODS: Retrospective analysis of a single surgeon experience in a district general hospital RESULTS: The cohort was 55 patients (52 female, 3 male), mean age 48 years (range, 21-77 years) who had 64 MIVAT procedures. There were 49 hemithyroidectomies (HTs), 2 isthmusectomy, 4 total thyroidectomies (TTs) and 9 completion thyroidectomies (CTs) with median operating time of 86 min (IQR 66-110 min). Individual operating times were HT 85 min (IQR 60-110 min); TT 130 min (IQR 100-140 min) and CT 77 min (IQR 70-98 min). Median operating time was shorter in the second half of this series (76 min vs 92 min; P < 0.001). Length of stay was < 1 day in 92%. Conversions occurred in 6.3% with no haematoma or re-operation. Transient voice change was present in 7 (11%), permanent unilateral recurrent laryngeal nerve palsy in 2 (3%), and transient hypocalcaemia in 2 (3%). CONCLUSIONS: The first results from the UK are similar to those of other international centres. A single-surgeon practice can obtain results comparable to larger tertiary centres provided there is sufficient case-load. MIVAT is safe and effective, but has a steep learning curve with rapid improvement observed within first 30 cases. Future studies should focus on objective assessment of scar/cosmesis and cost-effectiveness. MIVAT is an acceptable alternative to open surgery in highly selected patients.

A blinded, randomised, controlled trial of stapled versus tissue glue closure of neck surgery incisions.

INTRODUCTION: Cosmetic acceptability of scar and neck mobility are important outcomes after collar line incision for neck surgery. This randomised, controlled trial compares these parameters in closures using tissue glue (Dermabond, Ethicon, UK) and skin staples. PATIENTS AND METHODS: Patients requiring a collar line incision were randomised to receiving tissue glue or staples for skin closure. Time for closure to be completed was recorded. Mobility of the neck was assessed using a visual analogue scale at 48 h and 1 week after surgery. At 6 weeks, cosmetic appearance was assessed using a linear 1-10 visual analogue scale by the patient, surgeon and an independent blinded assessor. Results were compared using appropriate statistical tests. RESULTS: Glued (n = 14) and stapled (n = 15) closures were performed for hemithyroidectomy (n = 8 versus 6), sub-total thyroidectomy (n = 2 versus 4), total thyroidectomy (n = 1 versus 4) and parathyroidectomy (n = 3 versus 1). Closure with tissue glue took significantly longer than with staples (mean, 95 versus 28 s; P < 0.001). Neck mobility scores were comparable at 48 h and 1 week (mean, 4.8 versus 4.4; P = 0.552: and 2.7 versus 2.6; P = 0.886). Cosmetic appearance at 6 weeks was comparable when patient (mean, 1.7 versus 1.8; P = 0.898), surgeon (mean, 2.6 versus 2.3; P = 0.633) and independent assessment (mean, 1.4 versus 1.9; P = 0.365) was performed. CONCLUSIONS: The use of glued skin closure may increase the duration of surgery but acceptable neck mobility and wound cosmesis can be achieved by the more rapid application of stapled skin closure in cervicotomy incisions.

Primary endoluminal stenting of transplant renal artery stenosis from cadaver and non-heart-beating donor kidneys.

This study evaluated the efficacy of primary endovascular stenting in cases of transplant renal artery stenosis (TRAS) from cadaver and non-heart-beating donor kidneys. Patients with TRAS (n = 13) from a single-centre transplant population (n = 476) were treated by primary percutaneous angioplasty and endovascular stenting. The short-term efficacy of this intervention is demonstrated in terms of serum creatinine, glomerular filtration rate (GFR) biochemical, anti-hypertensive medications and mean arterial blood pressure control. Stenting for TRAS was performed in male (n = 10) and female (n = 3) recipients. The median age at transplantation was 55 yr (range 10-67 yr). Stenting occurred at a median duration of 410 d post-transplantation (range 84-5799 d). Mean serum creatinine (pre, 247 micromol/L; post, 214 micromol/L; p = 0.002), GFR (pre, 82.6 mL/min; post, 100.9 mL/min; p < 0.001), arterial blood pressure (pre, 104 mmHg; post, 97 mmHg; p = 0.036) and the number of anti-hypertensive medications required (pre, 3.4; post, 3.0; p = 0.002) showed significant improvement after post-endovascular therapy. There were no serious complications encountered. Primary endovascular stenting of TRAS produces a significant improvement in biochemical parameters of renal graft function and in blood pressure stability, with the benefit of low patient morbidity and single arterial puncture. Primary endoluminal stenting of TRAS is a safe and effective procedure for the treatment of TRAS.

Reassessing models of hepatic extraction.

The aim of this investigation is to compare different mathematical models of the liver in the context of in vitro-in vivo correlation. We reanalyze drugs from the Houston reviews [1, 2], and compare the mathematical models. For the well-stirred model, a particular form of the distributed tubes model, and the dispersion model, fits are done to in vitro and in vivo intrinsic clearance data from microsomal and hepatocyte experiments. The distributed and dispersion models have decreased residuals as compared to the well-stirred model, but neither is to be clearly preferred over theother. It seems likely that drug-specific factors have a major impact on the quality of IVIVC correlations. While new experiments are needed to validate IVIVC models, our results indicate that improved correlation of in vitroand in vivo data is possible for high clearance drugs by using either a dispersion or distributed tube model rather than a well-stirred model.

Increased heterologous protein production in Aspergillus niger fermentation through extracellular proteases inhibition by pelleted growth.

The dependence of filamentous fungal protease secretion on morphology was investigated by employing the recombinant Aspergillus niger strain AB4.1[pgpdAGLAGFP] which contains a gene for the glucoamylase-GFP (green fluorescence protein) fusion protein. Different inoculum levels were used to obtain different sizes of pellet or free mycelia. The extracellular protease activity of the cultures varied with the pellet size and decreased dramatically when the morphology was changed from free mycelia to pellets. The culture with an optimal pellet size of 1.6 mm was obtained from an inoculum of 4 x 10(6) spores/mL. It resulted in a specific protease activity of 158 units/L, only one-third of that in free mycelial growth, and a maximum specific GFP yield of 0.98 mg/g (cell mass) compared to 0. 29 mg/g for free mycelial growth with an inoculum of 10(7) spores/mL. The results indicate that this bioprocessing strategy can be effectively used to inhibit protease activity in filamentous fungal fermentation and thereby to enhance heterologous protein production.

The logic of causation and the risk of paralytic poliomyelitis for an American child.

Beginning in January 1997, American immunization policy allowed parents and physicians to elect one of three approved infant vaccination strategies for preventing poliomyelitis. Although the three strategies likely have different outcomes with respect to prevention of paralytic poliomyelitis, the extreme rarity of the disease in the USA prevents any controlled comparison. In this paper, a formal inferential logic, originally described by Donald Rubin, is applied to the vaccination problem. Assumptions and indirect evidence are used to overcome the inability to observe the same subjects under varying conditions to allow the inference of causality from non-randomized observations. Using available epidemiologic information and explicit assumptions, it is possible to project the risk of paralytic polio for infants immunized with oral polio vaccine (1.3 cases per million vaccinees), inactivated polio vaccine (0.54 cases per million vaccinees), or a sequential schedule (0.54-0.92 cases per million vaccinees).

Stable production of a human growth hormone antagonist from CHO cells adapted to serum-free suspension culture.

Human growth hormone (hGH) is a polypeptide with 191 amino acids and a molecular mass of 22 kDa. An hGH analogue was created with a single amino acid substitution (glycine[G] 120 to arginine[R]) in the third alpha-helix of the hGH molecule. This hGH analogue, named hGHG120R, was found to be an hGH antagonist. It is a parenteral drug candidate for treating conditions in which hGH levels are abnormally high, as found in type I diabetics. Previously, a genetically engineered anchorage-dependent mouse L cell line was created that produced and secreted hGHG120R in culture media (Dulbecco's modified Eagle's medium, DMEM) supplemented with 5% NuSerum IV. A multistep downstream process was developed to purify hGHG120R. The process consisted of cell clarification, salt precipitation, membrane ultrafiltration, size exclusion chromatography, reversed phase high-performance liquid chromatography, phase separation, and lyophilization. Here, we present the development of a superior eukaryotic system using a proper combination of genetic elements, cell line, and media formulation. This system is suitable for the large-scale production of the recombinant protein and is superior to the previously developed system in that it increases the specific production rate and at the same time eases the burden of the purification process, in both time and efficiency. Dihydrofolate reductase mutant (DHFR-) Chinese hamster ovary (CHO) cells were used that were stably transfected with an expression vector in which the hGHG120R gene is driven by the relatively strong human cytomegalovirus-early gene regulatory region. The hGHG120R tested to be biologically active. These cells were then adapted to grow in suspension in CHO-S-SFM (serum-free media). High cell densities, typically 2.0 x 10(6) cells/mL were obtained from spinner flask cultures. Partial purification of hGHG120R from CHO cell cultured media revealed that the level of impurities in SFM was significantly lower than the serum-supplemented DMEM. This suggests that the salt precipitation and the SEC step need not be employed in the purification of hGHG120R from SFM. This would result in a reduction of the operating time by 50 h and boost the recovery yield of hGHG120R to 75%.

No-fault vaccine insurance: lessons from the National Vaccine Injury Compensation Program.

During the first eight years of the National Vaccine Injury Compensation Program (NVICP), 786 contested claims were resolved through published judicial opinions. The likelihood of compensation dependent in part on the closeness of the match between the described injury and a specified list of acknowledged untoward vaccine side effects. In addition, the chances of applicant success were influenced by the applicant's choice of attorney and expert witnesses, by the assignment of the Special Master to decide the case, and increasingly over time, by the applicant's ability to comply with procedural requirements. The majority of contested claims arose from pertussis immunizations. For pertussis claims, the goal of insulating manufacturers from product liability suits has been achieved by granting compensation to applicants whose injuries are not scientifically recognized effects of the vaccine. In spite of (or because of) this jarring contradiction between the legal and medical understanding of causation, vaccine availability and childhood immunization rates improved during the early years of the plan. The apparent success of the program may encourage the substitution of no-fault compensation plans for tort-based consumer protection for other products, both medical and nonmedical.

Disputed claims for pertussis vaccine injuries under the National Vaccine Injury Compensation Program.

BACKGROUND: The National Vaccine Injury Compensation Program (NVICP) provides no-fault compensation to victims of serious untoward vaccine reactions under the supervision of the Department of Health and Human Services (HHS). Special Masters of the Court of Federal Claims settle compensation disputes that arise between applicants and program administrators. The majority of published NVICP claim decisions concern disputes over the cause of neurologic illness or unexpected infant death following pertussis vaccination. METHODS: Information was collected from the published decisions to determine the medical characteristics of cases in which injuries were legally attributed to pertussis vaccination. Because of practical and statutory restrictions on the application process and the evolving nature of HHS claim denials, vaccinees in the disputed cases are not representative of all vaccine casualties, or of all NVICP applicants. RESULTS: Injuries were blamed on pertussis vaccine in 542 claims disputed by HHS. Claims asserted that pertussis vaccine caused seizure disorders (333 claims, 189 were awarded compensation), anaphylaxis (7 claims, 6 awards), hypotonic/hyporesponsive episodes or other injuries leading to early death (107 claims, 73 awards), and long-term neurologic disease (51 claims, 18 awards). CONCLUSIONS: Assertions that pertussis vaccine caused unexpected infant death (other than anaphylaxis), seizure disorders, and long-term neurologic damage are inconsistent with epidemiological research. Findings of legal causation may contribute to popular perceptions that pertussis vaccine is a dangerous biological product. By providing compensation for these claimants, however, the NVICP may reduce the number of successful civil suits and thus protect the nation's vaccine supply.

Overexpression of MARCKS, but not protein kinase C-alpha, increases phorbol ester-stimulated synthesis of phosphatidylcholine in human SK-N-MC neuroblastoma cells.

To investigate the regulation of phorbol ester-stimulated synthesis of phosphatidylcholine (PtdCho), myristoylated alanine-rich protein kinase C substrate (MARCKS) and the alpha-isoform of protein kinase C (PKC-alpha) were overexpressed in a human neuroblastoma (SK-N-MC) cell line that does not increase PtdCho synthesis in response to 4beta-12-O-tetradecanoylphorbol 13-acetate (TPA). In five clones with a less than fivefold increase in MARCKS protein level, the synthesis of PtdCho from [methyl-3H] choline was stimulated 1.88-2.34-fold in the presence of 100-200 nM TPA. In clones overexpressing PKC-alpha (30-40-fold increased level of protein) or in mock-transfected vector controls, TPA had much less of a stimulatory effect (1.04-1.43 fold) on PtdCho synthesis. TPA caused translocation of PKC-alpha and increased phosphorylation of MARCKS, indicating that both overexpressed proteins responded to stimulation. Thus, in SK-N-MC cells, MARCKS is required for TPA-stimulated synthesis of PtdCho and PKC-alpha alone is insufficient for supporting enhanced synthesis.