Microsurgical reconstruction of complicated extended latissimus dorsi flap donor sites: a report of three cases

The latissimus dorsi (LD) flap and its extended version are popular choices for reconstruction of the breast after mastectomy. Donor site complications such as seroma and wound dehiscence are relatively common with these flaps; however, severe donor site healing problems requiring major surgical intervention are not reported in the literature. We report three breast reconstructions with extended LD flaps in which the patients had severe healing problems of the donor site. Simpler, routine measures failed and free tissue transfer was necessary to achieve healing.

Phenytoin-induced gingival overgrowth

Gingival overgrowth is a common adverse effect of therapy with Phenytoin, having important medical and cosmetic implications. Poor periodontal hygiene is an important risk factor for severity of Phenytoin-induced gingival overgrowth (PIGO), which is a time-dependent process. There is complex interplay of altered fibroblast biology, connective tissue turnover, inflammatory processes, and growth factors on a background of genetic susceptibility to produce increase in various components of interstitial matrix in PIGO tissue. Treatment options have included change of PHT to another anti-seizure drug, measures to improve periodontal hygiene and gingivectomy. There is conclusive evidence that folic acid supplementation significantly decreases the incidence of PIGO.

Folic acid supplementation prevents phenytoin-induced gingival overgrowth in children

OBJECTIVE

Gingival overgrowth is an important adverse effect of phenytoin (PHT) therapy, occurring in about half of the patients. This study aimed to evaluate the effect of oral folic acid supplementation (0.5 mg/day) for the prevention of PHT-induced gingival overgrowth (PIGO) in children with epilepsy aged 6-15 years on PHT monotherapy for 6 months.

METHODS

This was a randomized, double-blind, placebo-controlled trial conducted at a tertiary level hospital from May 2008 to June 2009. Children aged 6-15 years started on PHT monotherapy within last 1 month were eligible for inclusion. Preexisting gingival overgrowth, use of other folic acid antagonists, and macrocytic anemia were exclusion criteria. Trial subjects were randomized to receive either folic acid or placebo. The primary outcome measure was incidence of any degree of gingival overgrowth after 6 months of PHT monotherapy. The trial was registered with clinicaltrials.gov (NCT00781196).

RESULTS

A total of 120 children were recruited, 62 and 58, respectively, in folic acid and placebo arms. The 2 arms were comparable at baseline. Twenty-one percent of patients in the folic acid arm developed PIGO, as compared with 88% receiving placebo (p < 0.001). Absolute risk reduction of PIGO by folic acid was 67% (95% confidence interval 54%-80%), and relative risk reduction was 0.76.

CONCLUSIONS

Oral folic acid was found to decrease the incidence of PIGO in children on PHT monotherapy, in a statistically significant and clinically relevant manner.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that folic acid supplementation, 0.5 mg/day, is associated with prevention of gingival overgrowth in children taking PHT monotherapy.

Technological Development for Commercialization of Amorphous Silicon Based Multijunction Modules

Some of the significant steps in technological development for large-scale commercialization of amorphous silicon (a-Si:H) based multijunction photovoltaic modules are presented. These developments are establishing a high quality baseline process for manufacturing large-area ( ˜ 8 ft2) a-Si:H/a-SiGe:H tandem junction modules with improved stabilized conversion efficiency, throughput, yield, and reduced materials usage.

The effect of estrone on thrombin generation may explain the different thrombotic risk between oral and transdermal hormone replacement therapy

BACKGROUND

The metabolism of estrogen contained within hormone replacement therapy (HRT) is influenced by the route of administration, and this may affect the risk of venous thromboembolism. Thrombin generation, a global coagulation assay, is a marker of hypercoagulability and is of potential use in determining the thrombotic risk associated with particular HRT administration routes.

OBJECTIVES

To determine whether any effect of oral and transdermal HRT on thrombin generation is related to the plasma estrogen profile.

METHODS

We investigated the effects of oral, transdermal and no HRT (controls) in 52, 39 and 52 postmenopausal women, respectively, on thrombin generation, standard markers of thrombophilia, estradiol level and estrone level.

RESULTS

All parameters of thrombin generation were altered in women using oral HRT as compared with controls (P<0.001 for all comparisons). No such differences were found in women using transdermal HRT. Estrone levels correlated with peak thrombin generation (R=0.451, P<0.001) in women using oral HRT, but there was no correlation in women using the transdermal route.

CONCLUSIONS

Thrombin generation is significantly increased in women who use HRT administered by the oral route. This is probably mediated by the hepatic first-pass metabolism of estrone, the main metabolite of oral estradiol, which is avoided by the transdermal route. The effect of estrone on thrombin generation may provide the explanation for the higher thrombotic risk seen in women using oral rather than transdermal HRT.

The use of an exclusion-based risk-assessment model for venous thrombosis improves uptake of appropriate thromboprophylaxis in hospitalized medical patients

BACKGROUND

Venous thromboembolism is a common condition in hospitalized medical patients. Numerous studies have demonstrated that low molecular weight heparin significantly reduces this risk but, despite this, the use of thromboprophylaxis remains poor.

AIM

To evaluate the use of an exclusion based risk-assessment model (RAM) for venous thrombosis in improving the uptake of appropriate thromboprophylaxis in hospitalized medical patients.

DESIGN

A survey with a subsequent audit cycle of three separate audits over 36 months.

METHODS

497 hospitalized patients with acute medical conditions on general medical wards were audited at a secondary care centre in London, UK. The survey and subsequent audits were performed by reviewing the notes and medication charts of medical patients, prior to the launch of the RAM and at 12, 28 and 36 months following its introduction.

RESULTS

Prior to launching the RAM, 49% of hospitalized medical patients received appropriate thromboprophylaxis. This did not change 12 months after the RAM was introduced but increased significantly to 71% following formal education of the health care professionals involved in thromboprophylaxis prescription. This improvement was maintained as demonstrated by a subsequent audit 8 months later (75.9%).

CONCLUSION

The introduction of a simple exclusion-based RAM for venous thrombosis in medical patients significantly improved delivery of thromboprophylaxis. The successful uptake of the RAM appears to have been dependent on direct education of those health carers involved in its use. A similar exclusion-based model used nationally could have a significant impact on the burden of VTE currently experienced in the UK.

Frequency, demographics and risk (according to tumour type or site) of cancer-associated thrombosis among patients seen at outpatient DVT clinics

Venous thromboembolism (VTE) is a clinically important complication for both hospitalised and ambulatory cancer patients. In the current study, the frequency, demographics and risk (according to tumour site) of VTE were examined among patients seen at outpatient DVT (deep-vein thrombosis) clinics. Of 10,015 VTE cases, 1,361 were diagnosed with cancer, for an overall rate of cancer-associated VTE of 13.6% in this outpatient population. Patients with cancer-associated VTE were significantly older than cancer-free VTE cases (66.4 +/- 12.7 vs. 58.8 +/- 18.5 years; p<0.0001). The frequency of cancer-associated VTE peaked earlier among females than males, occurring in the sixth (137/639, 21.4% vs. 98/851, 11.3%; p<0.001) and seventh decades (213/980, 21.7% vs. 197/1096, 18%; p=0.036). VTE was described most frequently in common cancers - breast, prostate, colorectal and lung (56.1% of cases). The risk of VTE varied widely across 17 cancer types. Calculating odds ratios (OR) to assess the effect size of cancer type on VTE risk, the highest odds were observed for patients with pancreatic cancer (OR 9.65, 95% confidence interval [CI] (5.51-16.91). Tumours of the head and neck had higher odds than previously reported (OR 8.24, 95% CI 5.06-13.42). Reduced risk estimates were observed for skin cancers (melanoma and non-melanoma: OR 0.89, 95% CI 0.42-1.87; OR 0.74, 95% CI, 0.32-1.69, respectively). We conclude that outpatients have a similar rate of cancer-associated VTE as VTE patient populations previously reported, that cancer-associated VTE occurs in an older age group and earlier in females and that outpatients exhibit distinct tumour site-specific risk from that described among hospitalised cancer patients.

Association between variants in the genes for adiponectin and its receptors with insulin resistance syndrome (IRS)-related phenotypes in Mexican Americans

AIMS/HYPOTHESIS

The aim of this study was to examine whether genetic variation in ADIPOQ, ADIPOR1 and ADIPOR2 may contribute to increased susceptibility to components of the insulin resistance syndrome (IRS).

MATERIALS AND METHODS

We genotyped single-nucleotide polymorphisms (SNPs) in ADIPOQ, ADIPOR1 and ADIPOR2 in Mexican American subjects (N=439) and performed an association analysis of IRS-related traits.

RESULTS

Of the eight SNPs examined in the ADIPOQ gene, rs4632532 and rs182052 exhibited significant associations with BMI (p=0.029 and p=0.032), fasting specific insulin (p=0.023 and p=0.026), sum of skin folds (SS) (p=0.0089 and p=0.0084) and homeostasis model assessment of insulin sensitivity (HOMA-%S) (p=0.015 and p=0.016). Two other SNPs, rs266729 and rs2241767, were significantly associated with SS (p=0.036 and p=0.013). SNP rs7539542 of ADIPOR1 was significantly associated with BMI, SS and waist circumference (p=0.025, p=0.047 and p=0.0062). Fourteen of the ADIPOR2 SNPs were found to be significantly (p<0.05) associated with fasting plasma triglyceride concentrations. Four of these SNPs (rs10848569, rs929434, rs3809266 and rs12342) were in high pairwise linkage disequilibrium (r (2)=0.99) and were strongly associated with fasting triglyceride levels (p=0.00029, p=0.00016, p=0.00027 and p=0.00021). Adjusting for the effects of BMI and HOMA-%S on triglyceride concentrations increased significance to p=0.000060 for SNP rs929434. Bayesian quantitative trait nucleotide analysis was used to examine all possible models of gene action. Again, SNP rs929434 provided the strongest statistical evidence of an effect on triglyceride concentrations.

CONCLUSIONS/INTERPRETATION

These results provide evidence for association of SNPs in ADIPOQ and its receptors with multiple IRS-related phenotypes. Specifically, several genetic variants in ADIPOR2 were strongly associated with decreased triglyceride levels.

Sharp dissection versus electrocautery for radial artery harvesting

Radial arteries have been increasingly used during the last decade as conduits for coronary artery revascularization. Although various harvesting techniques have been described, there has been little comparative study of arterial damage and patency. A radial artery graft was used in 44 consecutive patients, who were randomly divided into 2 groups. In the 1st group, the radial artery was harvested by sharp dissection and in the 2nd, by electrocautery. These groups were compared with regard to radial artery free flow, harvest time, number of clips used, complications, and endothelial damage. Radial artery free flow before and after intraluminal administration of papaverine was significantly greater in the electrocautery group (84.3 +/- 50.7 mL/min and 109.7 +/- 68.5 mL/min) than in the sharp-dissection group (52.9 +/- 18.3 mL/min and 69.6 +/- 28.2 mL/ min) (P=0.003). Harvesting time by electrocautery was significantly shorter (25.4 +/- 4.3 min vs 34.4 +/- 5.9 min) (P=0.0001). Electrocautery consumed an average of 9.76 clips, versus 22.45 clips consumed by sharp dissection. The 2 groups were not different regarding postoperative complications, except for 3 cases of temporary paresthesia of the thumb in the electrocautery group; histopathologic examination found no endothelial damage. We conclude that radial artery harvesting by electrocautery is faster and more economical than harvesting by sharp dissection and is associated with better intraoperative flow and good preservation of endothelial integrity.

Incidence of genital Chlamydia trachomatis infection in the male partners attending an infertility clinic

Chlamydia trachomatis is an important pathogen in the aetiology of pelvic inflammatory disease, resulting in female infertility. If all female infertility patients are screened for silent genital chlamydia infection, should the male partners of these patients also be screened to decrease the risk of re-infection? To determine the incidence of current and present male infection with C. trachomatis, we carried out a prospective clinical study. We studied 100 consecutive new male partners of patients seen in the infertility clinic. The infertility was of at least 12 months duration. We used polymerase chain reaction detection of C. trachomatis in urine specimens and microimmunofluorescence serology was performed to detect both past and current infection. The female partners were also screened for chlamydia infection by cervical swabs and serology. In five male patients (5%) C. trachomatis DNA was detected in the urine specimen by polymerase chain reaction. Microimmunofluorescence serology was positive in five patients (5%). One of the subjects had positive serology and urine polymerase chain reaction testing. The proportion of male partners with current or previous C. trachomatis infection was therefore 9% (95% CI 3.39 - 14.60). Seven female patients had positive serology results (7%), one of whom also had a positive cervical swab result indicating current infection with the pathogen. In four cases, both the male and female partner had positive serology results. The cost of screening for C. trachomatis is cheaper than treating the complications of undiagnosed genital Chlamydia infection, which is implicated in tubal disease leading to infertility. The results suggest that routine screening of male partners in an infertility setting may be justified.

Haemorrhagic bullae in a case of paroxysmal nocturnal haemoglobinuria

Paroxysmal nocturnal haemoglobinuria is a clonal stem cell disorder manifesting as haemolysis, bone marrow failure and thrombosis. We report a rare cutaneous manifestation on the trunk of a 40-year-old patient. Skin biopsy revealed the presence of fibrin thrombi in the capillaries. The eruption responded within days after commencing oral corticosteroids.

Power to localize the major gene for disease liability is increased after accounting for the effects of related quantitative phenotypes

We used the simulated general population data for Genetic Analysis Workshop 12 to test whether power to localize the major gene for liability to disease is increased after accounting for the effects of correlated quantitative phenotypes. We performed the multipoint variance-component linkage analyses for the discrete trait twice: first analysis with age, sex, and EF1 as covariates, and the second analysis with age, sex, EF1, and Q1-Q5 as covariates. Major locus heritability (h2q) (0.80 +/- 0.06) and lod score (6.4) averaged over the number of replicates used are significantly higher in the second analysis compared with the first analysis (h2q = 0.39 +/- 0.12, lod = 2.6). Thus, in the present analysis, power to detect linkage and localize the genes for liability to disease appears to be increased after accounting for the effects of five quantitative traits that are correlated with the liability.

Internal jugular vein thrombosis after assisted conception therapy

Superovulation therapy during assisted conception may result in a hypercoagulable state. Five cases of upper extremity venous thrombosis were identified in women who conceived after ovarian stimulation for in vitro fertilization (IVF). They presented between 7 and 10 weeks' gestation with neck pain and swelling. Three had been treated for ovarian hyperstimulation syndrome and two had evidence of inherited thrombophilia. Four patients received thromboprophylaxis before presentation. Although thrombosis is an uncommon complication of IVF, patients should be counselled before treatment. Thrombophilia screening may be considered for 'high-risk' patients, although current regimes for thromboprophylaxis remain suboptimal.

A major locus for fasting insulin concentrations and insulin resistance on chromosome 6q with strong pleiotropic effects on obesity-related phenotypes in nondiabetic Mexican Americans

Insulin resistance and hyperinsulinemia are strong correlates of obesity and type 2 diabetes, but little is known about their genetic determinants. Using data on nondiabetics from Mexican American families and a multipoint linkage approach, we scanned the genome and identified a major locus near marker D6S403 for fasting "true" insulin levels (LOD score 4.1, empirical P<.0001), which do not crossreact with insulin precursors. Insulin resistance, as assessed by the homeostasis model using fasting glucose and specific insulin (FSI) values, was also strongly linked (LOD score 3.5, empirical P<.0001) with this region. Two other regions across the genome were found to be suggestively linked to FSI: a location on chromosome 2q, near marker D2S141, and another location on chromosome 6q, near marker D6S264. Since several insulin-resistance syndrome (IRS)-related phenotypes were mapped independently to the regions on chromosome 6q, we conducted bivariate multipoint linkage analyses to map the correlated IRS phenotypes. These analyses implicated the same chromosomal region near marker D6S403 (6q22-q23) as harboring a major gene with strong pleiotropic effects on obesity and on lipid measures, including leptin concentrations (e.g., LOD(eq) for traits-specific insulin and leptin was 4.7). A positional candidate gene for insulin resistance in this chromosomal region is the plasma cell-membrane glycoprotein PC-1 (6q22-q23). The genetic location on chromosome 6q, near marker D6S264 (6q25.2-q26), was also identified by the bivariate analysis as exerting significant pleiotropic influences on IRS-related phenotypes (e.g., LOD(eq) for traits-specific insulin and leptin was 4.1). This chromosomal region harbors positional candidate genes, such as the insulin-like growth factor 2 receptor (IGF2R, 6q26) and acetyl-CoA acetyltransferase 2 (ACAT2, 6q25.3-q26). In sum, we found substantial evidence for susceptibility loci on chromosome 6q that influence insulin concentrations and other IRS-related phenotypes in Mexican Americans.

Chediak-Higashi syndrome--a case report

Chediak Higashi anomaly is a very rare disorder in which patients suffer frequent and severe pyogenic infections that are secondary to abnormal functions of polymorphonuclear leukocytes, associated with albinism and bleeding tendency. Blume RS and Wolff SM (1972) reported that only 59 cases were diagnosed after the first description of Chediak-Higashi Syndrome in 1943 by Cesar AB (cited by Wintrobe MM Clinical Haematology). As per recent literature available (Internet) last case was reported on 16th July, 1997.

Evidence for founder effect of the Glu104Asp substitution and identification of new mutations in triosephosphate isomerase deficiency

Triosephosphate isomerase (TPI) deficiency is an autosomal recessive disorder of glycolysis characterized by multisystem disease and lethality in early childhood. Among seven unrelated Northern European kindreds with clinical TPI deficiency studied, a single missense mutation at codon 104 (GAG;Glu-->GAC;Asp) predominated, accounting for 11/14 (79%) mutant alleles. In three families molecular analysis revealed compound heterozygosity for Glu104Asp and novel missense mutations. In two cases the second mutation was a Cys to Tyr substitution at codon 41 (TGT-->TAT) and in one an Ile to Val substitution at codon 170(ATT-->GTT). The origin of the Glu104Asp mutation was defined by haplotype analysis using a novel G/A polymorphism at nucleotide 2898 of the TPI gene. Cosegregation of the low frequency 2898A allele with the G-->C base change at nucleotide 315 supports a single origin for the Glu104Asp mutation in a common ancestor.

Temporal expression of tumor necrosis factor-alpha and nitric oxide synthase 2 in rat small intestine after endotoxin

Temporal changes in tumor necrosis factor-alpha (TNF-alpha) and nitric oxide synthase 2 (NOS 2) were evaluated in segments of duodenum, jejunum, and ileum removed from male Sprague-Dawley rats 30, 60, 120, 180, and 240 min after lipopolysaccharide (LPS), 5 mg/kg, intraperitoneally. Plasma was assayed for TNF-alpha and for nitrate/nitrite (NOx). Intestinal and plasma TNF-alpha were elevated by 60 min after LPS and were back to control levels by 180 min. For control rats, NOS 2 was detected in the ileum, but not in the duodenum or the jejunum. In rats treated with LPS, NOS 2 was detected in all areas of the intestine at 120 min and was greatest at 240 min. Plasma NOx was elevated at 120 min and continued to increase to 240 min. The time course of changes in intestinal TNF-alpha and NOS 2 were similar to those reported for other tissues and suggest that the early and late actions of the LPS on the intestine may involve both mediators.

Absence of lipophosphoglycan-like glycoconjugates in Entamoeba dispar

Invasive amoebiasis is the result of infection of Entamoeba histolytica. The closely related Entamoeba dispar can colonize the human gut but does not cause invasive disease. In this study, E. dispar was analysed for the presence of the lipophosphoglycan-like (LPG) glycoconjugate known to be present on the cell surface of E. histolytica. E. dispar cells were radio-isotope labelled with [3H]galactose or [3H]inositol. The acidic glycoconjugates were extracted and analysed by hydrophobic chromatography over phenyl-Sepharose and by sodium dodecyl sulphate polyacrylamide gel electrophoresis. No LPG-like molecules could be identified in E. dispar in contrast to E. histolytica, suggesting that these molecules may be absent in the non-pathogenic species.

Reversal of metabolic block in glycolysis by enzyme replacement in triosephosphate isomerase-deficient cells

Inherited deficiency of the housekeeping enzyme triosephosphate isomerase (TPI) is the most severe clinical disorder of glycolysis. Homozygotes manifest congenital hemolytic anemia and progressive neuromuscular impairment, which in most cases pursues an inexorable course with fatal outcome in early childhood. No effective therapy is available. Hitherto specific enzyme replacement has not been attempted in disorders of glycolysis. Primary skeletal muscle myoblasts and Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines generated from homozygous TPI-deficient patients were cultured in the presence of exogenous enzyme or cocultured with human K562 erythroleukemia cells as an exogenous source of TPI. Uptake of active enzyme by TPI-deficient cells resulted in reversal of intracellular substrate accumulation, with a reduction in dihydroxyacetone phosphate (DHAP) concentration to levels seen in TPI-competent cells. Evidence of successful metabolic correction of TPI deficiency in vitro establishes the feasibility of enzyme replacement therapy, and has important implications for the potential role of allogeneic bone marrow transplantation and gene therapy as a means of sustained delivery of functional enzyme in vivo.

Genetic variation in the population of Ibiza (Spain): genetic structure, geography, and language

A sample of 203 individuals from Ibiza (Balearic Islands, Spain) were tested for blood group and serum protein genetic variation and compared with other circum-Mediterranean populations. Allele frequencies were calculated for the following blood group and serum systems: ABO, Rh, MNSs, P, Lewis, Duffy, Kell, ORM, GC, TF, PI, and HP. The allele frequencies from Ibiza were compared with those from other Balearic Islands (Majorca and Minorca) and with related European and North African groups using an assortment of analytical methods (genetic distances, R matrix analysis, and Mantel tests). R matrix analysis revealed that Ibiza is genetically different from the other Balearic populations and, because of gene flow from Spain, clusters with European groups. The level of genetic microdifferentiation of the Mediterranean populations, measured by RST (average of the R matrix diagonal elements, rii), is 0.028. An examination of the relationship between genetic, geographic, and linguistic distances by Mantel tests revealed that genetic distances are significantly correlated with linguistic distances, whereas the genetic distances are not significantly correlated with geographic distances. The plot of mean per locus heterozygosity versus the genetic distance from the centroid of distribution revealed that all three Balearic Islands have experienced considerable gene flow but that Ibiza has been most affected by the action of stochastic processes.

Two novel mutations in the reduced nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase gene of a patient with generalized type, hereditary methemoglobinemia

Hereditary methemoglobinemia due to reduced nicotinamide adenine dinucleotide (NADH) cytochrome b5 reductase (b5R) deficiency is classified into two types, an erythrocyte (type I) and a generalized (type II). We investigated the b5R gene of a patient with type II from a white United Kingdom (UK) family and found that the patient was a compound heterozygote for two novel mutations. The first mutation was a C-to-A transversion changing codon 42 (TAC: Tyr) to a stop codon in the one allele. From this mutant allele, the product without the catalytic portion of the enzyme is generated. The second one was a missense mutation at codon 95 (CCC-->CAC) in the other allele with the result that Pro changed to His within the flavin adenine dinucleotide (FAD)-binding domain of the enzyme. To characterize effects of this missense mutation on the enzyme function, we compared glutathione S-transferase (GST)-fused b5R with the GST-fused mutant enzyme with the codon 95 missense mutation (P95H) expressed in Escherichia coll. The mutant enzyme showed less catalytic activity, less thermostability, and a greater susceptibility to trypsin than did the normal counterpart. The absorption spectrum of the mutant enzyme in the visual region differed from that of the wild-type. These results suggest that this amino acid substitution influences both secondary structure and catalytic activity of the enzyme. The compound heterozygosity for the nonsense and the missense mutations apparently caused hereditary methemoglobinemia type II in this patient.

Outcome in low risk pregnancies

AIMS

To determine the obstetric and neonatal outcomes of a cohort of very low risk pregnancies in hospital, that would be suitable for home delivery.

METHODS

A retrospective analysis was undertaken of computerised records covering five years from July 1988 to August 1993 of 32424 pregnant women who delivered at the North Staffordshire Maternity Hospital, Stoke on Trent, during that period.

RESULTS

Of 32424 deliveries, only 1314 (4%) fulfilled our criteria for being low risk. Sixty seven (5.1%) of the low risk group had an operative delivery, with Caesarean section accounting for 32 (2.4%) cases, 16 (23.9%) babies were resuscitated and three were intubated. A normal vaginal delivery occurred in 1245 women, but a paediatrician attended 122 births (9.22%), assisted ventilation was provided in 65 cases (5.2%), and five babies were intubated (0.4%). Fourteen babies in total were admitted to the neonatal unit and one died.

CONCLUSIONS

These results suggest that at least 5% of women suitable for delivery at home will require transfer in labour. Midwives attending home births must be skilled in bag and mask resuscitation as only rarely will an urgent intubation be required. The British Paediatric Association Working Party report on neonatal resuscitation suggests a need for resuscitation in only 0.2% of low risk deliveries: but these findings suggest that the need is greater.

Tucaresol increases oxygen affinity and reduces haemolysis in subjects with sickle cell anaemia

The primary pathophysiological event in sickling is the intracellular polymerization of deoxygenated haemoglobin S. Tucaresol (589C80;4[2-formyl-3-hydroxyphenoxymethyl] benzoic acid), a substituted benzaldehyde, was designed to interact with haemoglobin to increase oxygen affinity and has been shown to inhibit sickling in vitro. We administered tucaresol to sickle cell patients in the steady state to examine the anti-sickling effect in vivo. Oral doses of tucaresol or placebo were given to nine stable sickle cell patients (aged 17-39 years; tucaresol, six; placebo, three) for 10 d. The first two patients on tucaresol were scheduled to receive a loading dose of 800 mg or 1200 mg (depending on bodyweight) for the first 4 d, followed by maintenance doses of 200 or 300 mg for the next 6 d. Due to concerns over the sharp rise in haematocrit in one patient, subsequent cohorts received 300 mg tucaresol daily throughout the dosing period. The oxygen affinity of haemoglobin S was increased in all patients receiving tucaresol, with between 10% and 24% of the haemoglobin modified, dependent on dose. In all patients on tucaresol, haemolysis was reduced with rises in haemoglobin of 0.9- 3.7 g/dl (mean 2.2 g/dl), falls in lactate dehydrogenase of 16-52%, and a halving of the irreversibly sickled cell counts. These effects were apparent within a few days and persisted for 1-2 weeks following discontinuation of the drug. Three of the six patients on tucaresol developed fever and cervical lymphadenopathy, with onset between days 7 and 11 from start of drug. Further evaluation of the tolerability and efficacy of tucaresol in sickle cell patients is necessary.

Prenatal diagnosis of triosephosphate isomerase deficiency

First-trimester prenatal diagnosis was undertaken by chorionic villus DNA analysis in two unrelated families with the inherited glycolytic disorder triosephosphate isomerase (TPI) deficiency. The propositus in each family was shown to be homozygous for a missense mutation (GAG --> GAC) at codon 104 of the TPI gene. In the first case the fetus was heterozygous for the codon 104 mutation and therefore clinically unaffected. Prenatal diagnosis in the second case showed the fetus to be homozygous for the codon 104 mutation and thus affected by TPI deficiency. This represents the first molecular diagnosis during early pregnancy of a human glycolytic enzyme disorder.

Retinopathy in haemoglobin C trait

Retinopathy associated with sickle-C and sickle cell disease is well described. Sickle trait and haemoglobin C trait are generally considered benign conditions, with infrequent systemic manifestations. Rare cases of retinopathy in sickle trait, in the presence of contributory factors, exist and we recently reported three such patients. The occurrence of retinopathy in haemoglobin C trait is even less well documented. Haemoglobin C does not cause red blood cell sickling but is known to decrease erythrocyte plasticity and increase blood viscosity. We report three cases in which haemoglobin C trait was associated with significant peripheral vascular occlusion and seafan formation (confirmed by fluorescein angiography) similar to that seen in sickle retinopathy. Two patients had coexistent systemic disease (hypertension and diabetes mellitus). Vitreous haemorrhage was the presenting feature in two patients. It is evident that haemoglobin C trait may be associated with sight-threatening complications.

Hereditary red cell enzymopathies

The hereditary red cell enzymopathies are an uncommon but important cause of chronic haemolytic anaemia. Their clinical diversity is mirrored by increasingly evident heterogeneity at the molecular level. The structure, function, and expression of the genes encoding red cell enzymes and the nature of the gene defects in the deficient state are examined.

Bipolar hemiarthroplasty in femoral neck fractures

Thirty-two elderly patients with a femoral neck fracture treated by bipolar hemiarthroplasty and 36 patients (matched for age) with an Austin-Moore hemiarthroplasty were followed-up and compared. Bipolar replacement resulted in a higher percentage of satisfactory results, less postoperative pain, greater range of movement, more rapid return to unassisted activity, fewer unsatisfactory results and no acetabular erosion. The device functioned as bipolar in all the cases studied for inner-bearing motion.

Screening for ophthalmic manifestations of sickle cell disease in the United Kingdom

There are marked variations in the manifestations of sickle disease in different populations. The ocular complications of this condition amongst the Afro-Caribbeans living in the United Kingdom have not previously been reported. We present the preliminary results of an ophthalmic screening programme at King's College Hospital, London. One hundred eyes of 50 patients with sickle cell disease were assessed. Full ocular examination was performed including fundus fluorescein angiography. We have looked at the haematological and clinical profile of the patients involved as well as the number of days spent in hospital during the year preceding the eye examination. The incidence of grade II retinopathy was found to be significantly higher than grade I in SC disease. This concurs with the results of the Jamaican screening and confirms that these patients are at higher risk of visual impairment than those with SS disease. Our results also agree with the Jamaican experience which suggest that visual morbidity is mostly due to complications of proliferative sickle retinopathy (PSR). However, the findings in patients without proliferative changes are different; in particular, angioid streaks leading to disciforms are an important cause of visual loss in Jamaica, but were not seen in any of the 98 eyes examined in this study. No correlation was found between the grade of retinopathy and age, sex, systemic complications and various haematological parameters except for the percentage of haemoglobin F, which was significantly higher in patients with grade I (7.6) compared with grade II (4.2) retinopathy (p = 0.0127).

Rapid synthesis and introduction of a protected EDTA-like group during the solid-phase assembly of peptides

A simple two-step procedure is reported for the synthesis of a tert-butyl ester protected form of an EDTA-like bifunctional chelating agent. This reagent can be easily introduced on any available amino group during the assembly of peptides on solid-phase supports. Using the model tetradecapeptide OVA(323-336), we have introduced an EDTA group at the N-terminus of this T-cell epitope and confirmed that the EDTA group is present on the molecule, can chelate metals, and does not affect the biological activity of the peptide.

The role of selective beta 1-blocker in the preoperative preparation of thyrotoxicosis: a comparative study with propranolol

Subtotal thyroidectomy was performed for hyperthyroidism on 130 patients; 95 treated before surgery with propranolol (Group I) and 35 given only metoprolol before surgery (Group II). These patient groups were compared with reference to preoperative medication, operative and immediate postoperative course, and late results with follow-up for one to five years. Clinical response was 100% in group II and 94.7% in group I. The median length of preoperative treatment was 7.96 +/- 1.84 days in group I and 6.25 +/- 1.73 days in group II (P less than 0.05). There were no serious adverse effects of the drugs in either treatment group. No anaesthesiologic or cardiovascular complication occurred during operation in either group. Ten patients in group I (10.5%) and six patients in group II (11.4%) observed hyperthyroid manifestations in the immediate postoperative period, eliminated by the administration of the propranolol/metoprolol, and no case of thyroid storm occurred. One patient in group II developed clinical hypocalcaemia. Two patients, one in each group, presented temporary unilateral recurrent laryngeal nerve paralysis. There were two recurrences of toxicity in group I (2.1%) and none in group II. Hypothyroidism occurred in 3 patients (2.3%) two of them were from group I and one was from group II. The postoperative hospital stay was 4.62 +/- 1.61 days in group I and 2.81 +/- 1.32 days in group II (P less than 0.05). One patient from group I died on the third postoperative day due to pulmonary oedema. The results suggest that metoprolol can be safely used and offers the advantages of desired clinical response, shorter preoperative preparation time, simplicity of dosage and shorter postoperative hospital stay in comparison to propranolol for preoperative treatment of hyperthyroidism.