Randomised trial of vitamin A supplementation in pregnant women in rural Malawi found to be anaemic on screening by HemoCue

OBJECTIVE

To assess the effects of vitamin A supplementation in women with anaemia during pregnancy.

DESIGN

Single-centre randomised controlled trial.

SETTING

Rural community in southern Malawi, central Africa.

POPULATION

Seven hundred women with singleton pregnancies at 12-24 weeks measured by ultrasound scan and with haemoglobin <11.0 g/dl by HemoCue screening method. Analysis was by intention to treat. All received iron and folate, and sulphadoxine/pyrimethamine for antimalarial prophylaxis.

METHODS

Women were randomised to receive oral supplementation with daily 5000 or 10,000 iu vitamin A, or placebo.

MAIN OUTCOME MEASURES

Anaemia, as assessed by Coulter counter, severe anaemia, iron status and indices of infection.

RESULTS

Vitamin A deficiency was, in this rural population, less common than predicted. Vitamin A supplementation had no significant impact on anaemia, severe anaemia, iron status and indices of infection. Vitamin A stores were less likely to be depleted at the end of pregnancy in supplemented groups.

CONCLUSIONS

Vitamin A supplementation programmes to reduce anaemia should not be implemented in similar antenatal populations in rural sub-Saharan Africa unless evidence emerges of positive benefit on substantive clinical outcomes. Introducing public health interventions of unknown benefit and with unclear biological mechanisms can divert scarce resources from clinical and social interventions more likely to impact maternal mortality.

Current practices of donor pancreas allocation in the UK: future implications for pancreas and islet transplantation*

Recent refinements in technique mean islet cell transplantation offers the chance of a cure to an increasing patient cohort with diabetes. Such developments put pressure upon the scarce resource of donor organs, with potential competition between the modalities of cellular and solid organ transplantation. This questionnaire based study examines current patterns of donor pancreas procurement and use. Reasons for non procurement are studied together with the attitudes of transplant professionals to pancreas allocation. The minority of potentially useful pancreata are currently made available to either whole pancreas or islet transplant programs. Whilst professionals appreciate the role of each modality, there is a need to define criteria for pancreas allocation to avoid under use of donor organs.

Ischaemic preconditioning in transplantation and major resection of the liver

BACKGROUND

Ischaemia-reperfusion injury (IRI) contributes significantly to the morbidity and mortality of transplantation and major resection of the liver. Its severity is reduced by ischaemic preconditioning (IP), the precise mechanisms of which are not completely understood. This review discusses the pathophysiology and role of IP in this clinical setting.

METHODS

A Medline search was performed using the keywords 'ischaemic preconditioning', 'ischaemia-reperfusion injury', 'transplantation' and 'hepatic resection'. Additional articles were obtained from references within the papers identified by the Medline search.

RESULTS AND CONCLUSION

The mechanisms underlying hepatic IRI are complex, but IP reduces the severity of such injury in several animal models and in recent human trials. Increased understanding of the cellular processes involved in IP is of importance in the development of treatment strategies aimed at improving outcome after liver transplantation and major hepatic resection.

Endovascular Management of Arterial Conduit Pseudoaneurysm after Liver Transplantation: A Report of Two Cases

We describe two cases of pseudoaneurysms in liver-transplant iliac artery conduits, which were successfully treated with endovascular stent grafting.

Progress in living donor liver transplantation

Living donor liver transplantation (LDLT) has the capacity to reduce the current discrepancy between the number of patients on the transplant waiting list and the number of available organ donors. For pediatric patients, LDLT has clearly reduced the number of waiting list deaths, providing compelling evidence for an increase in LDLT programs. This review discusses many of the recent advances in LDLT.

The surgical management of peritoneal dialysis catheters

Peritoneal dialysis is a safe and effective form of renal-replacement therapy. Its use is increasing as the gap widens between the number of patients waiting for renal transplants and the number of available organs. This article reviews the surgical considerations and complications of peritoneal dialysis that may present to general surgeons.

Reproductive health in rural Malawi: a population-based survey

OBJECTIVES

To assess pregnancy outcome, maternal mortality and health-seeking behaviour in a rural African population and to assess the effects on these of women's education, distance from a health centre and household type.

DESIGN

Descriptive population-based study.

SETTING

A rural community in southern Malawi.

POPULATION

All women living in the catchment area of a rural health centre.

METHODS

Interviews with women in 20,649 households using structured questionnaires.

MAIN OUTCOME MEASURES

Pregnancy outcome, the effect of women's education, distance from a health centre and household type on pregnancy outcome, maternal morbidity and estimates of maternal and perinatal mortality.

RESULTS

Educational level was lower for women than for men. A significant association was found between educational level and fertility. Women aged 45-49 reported an average of six pregnancies with four resulting in currently living children. Successful pregnancy outcome was more likely with increased education and if the woman lived closer to the health centre. Despite living an average of 5 km from the health centre, over 90% of women attended antenatal clinic with a mean of five visits. Assistance at delivery by a trained health care worker was more likely as education increased and was less likely as distance from the health centre increased. Maternal mortality was reported at 413 per 100,000 deliveries (95% CI 144-682). The perinatal mortality rate in this population was estimated at 30 per 1000. An increased perinatal mortality was noted for women who were delivered by a female relative. Perinatal mortality rates were similar for delivery by a traditional birth attendant or a trained nurse-midwife. Education and proximity to the health centre were both associated with improved outcome.

CONCLUSIONS

Many women in this rural community suffer the consequences of high pregnancy loss. Maternal and perinatal mortality are high. Improved education and skilled assistance at delivery can result in improved pregnancy outcome. Proximity of any household to a health centre has an effect on outcomes.

Fibrosis-associated gene expression in renal transplant glomeruli after acute renal allograft rejection

BACKGROUND

Acute allograft rejection is thought to be a risk factor for chronic allograft nephropathy, the cardinal features of which are vasculopathy, interstitial fibrosis and glomerulosclerosis. Fibrosis-associated genes might act as ad interim surrogate markers for chronic allograft nephropathy. The aim of this study was to determine mRNA expression of fibrosis-associated genes in glomeruli plucked from protocol renal transplant biopsies, in patients with or without a history of acute rejection.

METHODS

A consecutive series of 52 patients (31 male, 21 female) was assessed. Donor categories were cadaveric, living related or asystolic. Transplant recipients received either cyclosporin- or tacrolimus-based immunosuppression. Patients routinely underwent percutaneous needle-core renal transplant biopsy at 1 week, and 3 and 6 months. Acute rejection episodes were confirmed histologically and treated with intravenous methylprednisolone, or antithymocyte globulin if steroid resistant. Individual glomeruli were plucked and total mRNA was extracted. Fibrosis-associated genes were amplified by reverse transcriptase-polymerase chain reaction (PCR) and quantified by enzyme-linked immunosorbent assay.

RESULTS

The expression of both collagen type III (mean 0.42 versus 0.31 arbitrary units of PCR products corrected for a housekeeping gene) and collagen IV (mean 0.46 versus 0.42 arbitrary units) at 6 months did not differ between recipients who experienced acute rejection episodes and those who were free from rejection. There was also no significant difference between groups in terms of mRNA expression of collagen IValpha2, matrix metalloproteinase 2, tissue inhibitor of matrix metalloproteinases 1 and 2, transforming growth factor beta or tenascin.

CONCLUSION

These results suggest that acute rejection episodes do not increase the expression of fibrosis-associated genes in glomeruli from renal transplant biopsies.

Non-heart beating donor kidneys with delayed graft function have superior graft survival compared with conventional heart-beating donor kidneys that develop delayed graft function

Delayed graft function may have an association with reduced graft survival, and nonheart-beating donor (NHBD) kidneys have higher rates of delayed graft function (DGF) than heart-beating donor (HBD) kidneys. This study compared outcome of renal transplants from HBDs who developed DGF, with NHBDs who developed DGF. All recipients of HBD and NHBD kidneys who developed DGF were identified during a 10-year period. All patients with graft primary nonfunction were excluded from analysis. Four hundred and fifty-six functioning transplants were performed. Delayed graft function occurred in 69 (17%) HBD and 55 (93%) NHBD kidneys. The grafts developing DGF were well matched for donor and recipient age. The rate of acute rejection was similar; [n = 16/69 (23%) HBD vs. n = 13/55 (24%) NHBD]. Cold ischaemia was 21 h in the HBD group and 17 h in NHBD group (p > 0.05). Serum creatinine was similar for both groups at 1.3 and 6 years (p > 0.05 for all time points). Graft survival in the NHBD recipients with DGF was significantly better at 3 years (84%) compared with recipients of a HBD renal transplant that developed DGF (73%) (p < 0.05), and at 6 years (62% survival for HBDs and 84% survival for NHBDs). This study shows that graft survival was better for NHBD kidneys up to 6 years after transplantation.

Idiopathic chronic ulcerative enteritis--the role of radical surgical resection

Idiopathic chronic ulcerative enteritis is uncommon. It is a term that describes ulceration of the small bowel in the absence of a recognisable cause. Patients mainly present with a surgical abdomen and their management often proves to be a therapeutic challenge. Our series describes three such cases: the first patient presented with a tender left iliac fossa mass and rectal bleeding, the second with peritonitis and pneumoperitoneum, the third with severe acute colitis. All three patients needed urgent surgical intervention with further laparotomies due to recurrent ulceration, perforation and fistula formation in addition to intensive supportive measures such as inotropes and total parenteral nutrition. The importance and challenges of idiopathic chronic ulcerative enteritis are therefore discussed.

Pancreatic Islet Cell Transplantation

Pancreatic islet cell transplantation as a treatment for diabetes has hitherto been confined to small patient cohorts with limited success. This article summarizes the results of islet cell transplantation before and after the advent of the new 'Edmonton protocol' of immunosuppression and management of the donor pancreas. Adopting this regimen has achieved unprecedented success and renewed interest in this potential cure for diabetes. Central to recent improvements in the technique has been the transplantation of an adequate islet mass. Improved methods to procure, isolate, and purify islets for clinical use are now being adopted as a new 'gold standard'. The use of new immunosuppressive drugs has further improved clinical results. Corticosteroid sparing-based regimens, and agents such as humanized monoclonal antibodies, are likely to form the mainstay of immunosuppressive protocols with the aim of achieving donor-specific tolerance. Alternative sources of islet cells are also required to expand the technique in an era of reduced numbers of donor pancreata. Manipulation of stem cells and xenotransplantation may yet yield sufficient islets to overcome the problem of donor shortage. Islet cell transplantation now forms the basis of a prospective multicenter trial under the aegis of the Immune Tolerance Network. The results of this are awaited, but it appears that islet cell transplantation may yet emerge as an effective treatment option for some members of the diabetic population.

Unexplained fitting in three parturients suffering from postdural puncture headache

We present the cases of three women who, within a 6-month period, suffered post-partum generalized tonic-clonic seizures. All had received an epidural in labour for analgesia and were subsequently diagnosed as suffering from postdural puncture headache. All were treated for that headache with Synacthen and one also received sumatriptan before her seizures. All made satisfactory recoveries and were discharged home. None displayed classical patterns suggestive of pre-eclampsia, meningitis, cortical venous thrombosis or any other pathological process that might explain these events adequately, and the specific precipitating factors were left unidentified.

Color coding of sutures in laparoscopic perforated duodenal ulcer: a new concept

A simple modification for securing the omental patch during laparoscopic oversewing of perforated duodenal ulcers is presented. This new concept uses color coding of sutures to prevent confusion and suture "cut-out" during the tie-over of the omental patch. The concept of suture color-coding may be applicable to other laparoscopic procedures where identification of "suture pairs" is difficult.

NMR analysis of helix I from the 5S RNA of Escherichia coli

The structure of helix I of the 5S rRNA from Escherichia coli has been determined using a nucleolytic digest fragment of the intact molecule. The fragment analyzed, which corresponds to bases (-1)-11 and 108-120 of intact 5S rRNA, contains a G-U pair and has unpaired bases at its termini. Its proton resonances were assigned by two-dimensional NMR methods, and both NOE distance and coupling constant information have been used to calculate structural models for it using the full relaxation matrix algorithm of the molecular dynamics program XPLOR. Helix I has A-type helical geometry, as expected. Its most striking departure from regular helical geometry occurs at its G-U, which stacks on the base pair to the 5' side of its G but not on the base pair to its 3' side. This stacking pattern maximizes interstrand guanine-guanine interactions and explains why the G-U in question fails to give imino proton NOE's to the base pair to 5' side of its G. These results are consistent with the crystal structures that have been obtained for wobble base pairs in tRNAPhe [Mizuno, H., & Sundaralingam, M. (1978) Nucleic Acids Res. 5, 4451-4461] and A-form DNA [Rabbinovich, D., Haran, T., Eisenstein, M., & Shakked, Z. (1988) J. Mol. Biol. 200, 151-161]. The conformations of the terminal residues of helix I, which corresponds to bases (-1)-11 and 108-120 of native 5S RNA, are less well-determined, and their sugar puckers are intermediate between C2' and C3'-endo, on average.

Two-stage subtotal hepatectomy for metastatic adrenal adenocarcinoma, a case report

Adrenal adenocarcinoma is a rare tumor with a poor prognosis. We present a case of recurrent adrenal adenocarcinoma with synchronous bilobar liver metastases that was treated by a two-stage subtotal hepatectomy. A formal right hemihepatectomy was performed with cryotherapy to a left lobe metastasis that was subsequently resected after a period of hepatic regeneration.

Endoscopic-assisted intrathoracic oesophagogastrostomy without thoracotomy for tumours of the lower oesophagus and cardia

AIMS

This study aimed to evaluate the efficacy of a novel technique enabling a trans-hiatal oesophagectomy with intrathoracic anastomosis under direct vision, without thoracotomy.

METHODS

Trans-hiatal dissection of the oesophagus was performed using direct and laparoscopic visualization. The oesophagus was transected above the tumour with a linear endo-GIA-2 60 mum stapler. The stomach was transected and a gastric tube fashioned. The anvil of an appropriately sized CEEA circular stapler was modified enabling it to flatten. It was attached to a novel delivery system introduced under direct vision along a guidewire into the stapled oesophagus. The anvil was realigned to its original position in the distal oesophagus, docked with the body of the stapler and an intrathoracic anastomosis performed.

RESULTS

Ten patients (female n=3, male n=7) aged from 39--77 years (mean age 65 years), ASA 2--3 with distal third tumours were treated. Duration of procedure ranged from 2--5 hours (mean 4 hours). One patient suffered a post-operative chest infection and an anastomotic leak treated successfully with a self-expanding metal stent. Hospital stay ranged from 6--28 days (mean 17 days). There was no mortality.

CONCLUSION

This technique allows a safe intrathoracic anastomosis to be performed trans-hiatally under direct vision, avoiding the need for thoracotomy in patients with high comorbidity.

The "open" and "closed" structures of the type-C inorganic pyrophosphatases from Bacillus subtilis and Streptococcus gordonii

Recently, a new class of soluble inorganic pyrophosphatase (type-C PPase) has been described that is not homologous in amino acid sequence or kinetic properties to the well-studied PPases (types A and B) found in many organisms from bacteria to humans and thought to be essential to the cell. Structural studies of the type-C PPases from Streptococcus gordonii and Bacillus subtilis reveal a homodimeric structure, with each polypeptide folding into two domains joined by a flexible hinge. The active site, formed at the interface between the N and C-terminal domains, binds two manganese ions approximately 3.6 A apart in a conformation resembling binuclear metal centres found in other hydrolytic enzymes. An activated water molecule bridging the two metal ions is likely poised for nucleophilic attack of the substrate. Importantly, the S. gordonii and B. subtilis enzymes have crystallised in strikingly different conformations. In both subunits of the S. gordonii crystal structure (1.5 A resolution) the C-terminal domain is positioned such that the active site is occluded, with a sulphate ion bound in the active site. In contrast, in the B. subtilis structure (3.0 A resolution) the C-terminal domain is rotated by about 90 degrees, leaving the active site wide open and accessible for substrate binding.

Use of non-heart-beating donors in renal transplantation

The rate of renal transplantation has plateaued and is now limited by the number of donor organs available. In the past all donor kidneys came from living donors or controlled non-heart beating donors. It was not until the introduction of brainstem death criteria that cadaveric heart beating donors became the main source. Recently, there has been renewed interest in non-heart beating donors, who have already suffered cardiorespiratory arrest. Kidneys from these donors have a unique set of problems associated with increased duration of warm ischaemia. To minimise this, the kidneys are cooled in situ using an intra-aortic balloon catheter and are perfused with cold hyperosmolar citrate. Retrieval can then proceed in the normal fashion. Despite a higher level of delayed graft function, the results from non-heart beating renal transplantation are good, with long term function comparable to cadaveric organs. If used safely, they enable significant expansion of the donor pool. Techniques in the future, such as machine perfusion preservation, may further improve the results from non-heart beating programmes.

The heterotrimer of the membrane-peripheral components of transhydrogenase and the alternating-site mechanism of proton translocation

Transhydrogenase undergoes conformational changes to couple the redox reaction between NAD(H) and NADP(H) to proton translocation across a membrane. The protein comprises three components: dI, which binds NAD(H); dIII, which binds NADP(H); and dII, which spans the membrane. Experiments using isothermal titration calorimetry, analytical ultracentrifugation, and small angle x-ray scattering show that, as in the crystalline state, a mixture of recombinant dI and dIII from Rhodospirillum rubrum transhydrogenase readily forms a dI(2)dIII(1) heterotrimer in solution, but we could find no evidence for the formation of a dI(2)dIII(2) tetramer using these techniques. The asymmetry of the complex suggests that there is an alternation of conformations at the nucleotide-binding sites during proton translocation by the complete enzyme. The characteristics of nucleotide interaction with the isolated dI and dIII components and with the dI(2)dIII(1) heterotrimer were investigated. (a) The rate of release of NADP(+) from dIII was decreased 5-fold when the component was incorporated into the heterotrimer. (b) The binding affinity of one of the two nucleotide-binding sites for NADH on the dI dimer was decreased about 17-fold in the dI(2)dIII(1) complex; the other binding site was unaffected. These observations lend strong support to the alternating-site mechanism.

Learning to communicate

Of the few animal groups that learn their vocalizations, songbirds are uniquely amenable to molecular, physiological, and behavioral analyses of the neural features responsible for vocal learning. In order to communicate effectively as an adult, a young songbird recognizes and memorizes a model of his species-specific song during a developmentally critical period called sensory acquisition. Factors are now emerging that contribute to the length and strength of this learning phase. In a second critical period, known as sensorimotor learning, the young bird uses auditory feedback to perfect his motor performance, creating a match to the memorized model. New studies show that motor matching can persist beyond sensorimotor learning, and thus a role for the acquired model might also persist into adulthood. Fascinating in their own right, songbirds also provide optimism that mature brains have recourse to plasticity.