Provision of long-term vascular access for haemodialysis in a patient with exhausted superficial arm veins

Prospective randomized multicentre trial comparing stapled with open haemorrhoidectomy (Br J Surg 2001; 88: 669–74)

Letter : M. Pescatori, Coloproctology Unit, Villa Claudia Hospital, Via Flaminia Nuova 280, 00191 Rome, Italy

Author's reply : D. F. Altomare, Department of Emergency and Organ Transplantation, General Surgery and Liver Transplantation Units, University of Bari, Policlinico, Piazza G. Cesare, 11–70124 Bari, Italy

Provision of long-term vascular access for haemodialysis in a patient with exhausted superficial arm veins (Br J Surgery 2001; 88: 484–5)

Letter : S. Sinha, A. K. Sharma, Sir Peter Medawar Unit, Royal Liverpool University Hospital, Liverpool L7 8XP, UK

Chronic pain and quality of life following open inguinal hernia repair (Br J Surgery 2001; 88: 1122–6)

Letter : W. Silen, Harvard Medical School, 710 Wellesley Street, Weston, Massachusetts 02493-1000, USA

One thousand consecutive gastrectomies without operative mortality

Letter : T. Sano, H. Katai, M. Sasako, K. Maruyama, Gastric Surgery Division, National Cancer Center Hospital, Tokyo 104–0045, Japan.

DNA vaccines: future strategies and relevance to intracellular pathogens

Increasing awareness of microbial threat has rekindled interest in the great potential of vaccines for controlling infectious diseases. The fact that diseases caused by intracellular pathogens cannot be overcome by chemotherapy alone has increased our interest in the generation of highly efficacious novel vaccines. Vaccines have proven their efficacy, as the immunoprotection they induce appears to be mediated by long-lived humoral immune responses. However, there are no consistently effective vaccines available against diseases such as tuberculosis and HIV, and other infections caused by intracellular pathogens, which are predominantly controlled by T lymphocytes. This review describes the T-cell populations and the type of immunity that should be activated by successful DNA vaccines against intracellular pathogens. It further discusses the parameters that need to be fulfilled by protective T-cell Ag. We then discuss future approaches for DNA vaccination against diseases in which cell-mediated immune responses are essential for providing protection.

Recombinant mycobacterial proteins future directions to improve protective efficacy

A large number of subunit vaccine candidates have recently been developed as alternatives to Mycobacterium bovis Bacillus Calmette-Guerin (BCG), which gives unpredictable and highly variable protection against tuberculosis. Immunological potential of various recombinant proteins against mycobacterial infections has been discussed. Further, strategies have been suggested, which include development of constructs coexpressing cytokines or regimens utilizing recombinant proteins for further improving the protective efficacy.

Knowledge amongst adult population regarding vectors of malaria in 21 states of India

Malaria is the world's most important tropical disease which kills more people than any other disease except tuberculosis. It is a public health problem in more than 90 countries, inhabited by a total of some 2400 million people, 40% of the world's population. More than 90% of all malaria cases are in sub Saharan Africa, with two thirds of the remainder concentrated in six countries viz. India, Brazil, Sri Lanka, Afghanistan, Vietnam and Columbia in decreasing order of prevalence. Even now the problem of malaria in India is grossly underestimated. A rough estimate of morbidity due to malaria made on the basis of consumption of antimalarials comes to 35.5 million episodes in addition to malaria cases treated by the National Anti Malaria Programme (NAMP). In addition to large scale morbidity and mortality, it affects agricultural and industrial produce causing great socioeconomic losses.

Lactoferrin-melanin interaction and its possible implications in melanin polymerization: crystal structure of the complex formed between mare lactoferrin and melanin monomers at 2.7-A resolution

The concentration of melanin determines the intensity of colors of the skin and hair of animals. Melanin pigments are tyrosine-based polymers formed in melanocytes within specialized organelles called melanosomes. In order to understand the mechanism of melanin polymerization, lactoferrin, a basic protein with a pI value of 9.0, has been used to produce melanin. Lactoferrin is a monomeric iron-binding protein with a molecular weight of 80 kDa. The crystals of lactoferrin were soaked in a solution containing dihydroxyphenylalanine (DOPA) and tyrosinase enzyme. These crystals were used for X-ray intensity data collection. The intensity data were collected to 2.7-A resolution to an overall completeness of 91% with an R(sym) of 0.071. The crystals belong to orthorhombic space group P2(1)2(1)2(1) with cell dimensions: a = 85.0 A, b = 99.8 A, c = 103.4 A. The structure was determined by molecular replacement method, using the model of diferric mare lactoferrin, and refined to an R-factor 0.215 (R(free) = 0.287) for all the data to 2.7-A resolution. The final model comprises 5,281 protein atoms from 689 amino acids, 2Fe(3+), 2CO(2-)(3) ions, 2 indole-5,6-quinone molecules (IQ), and 73 water molecules. Two IQ molecules, one in each lobe, bind to lactoferrin. In the C-lobe, the IQ binds in the iron-binding cleft, whereas in the N-lobe, it is located in the side pocket between two alpha-helices, filled with solvent molecules in the native iron-saturated mare lactoferrin. The IQ molecules interact with protein molecule mainly through glutamic acid in both lobes, without significant perturbation to the protein structure. The orientation of N- and C-lobes in the present structure is similar to that observed in the native iron-saturated protein. However, as a result of the binding of IQ molecules, the orientations of the domains N1, N2 and C1, C2 in the two cases differ slightly.

Citrus tissue culture employing vegetative explants

Citrus being a number one fruit of the world due to its high nutritional value, huge production of fruits and fruit products, the citrus industry may be considered a major fruit industry. Though citrus orchard area in India is comparable to USA, the produce is far less, while its export is nil. Biotechnology has played an outstanding role in boosting the citrus industry, e.g., in Spain, which is now the biggest exporter of citrus fruit with the application of micrografting. Amongst the fruit trees, perhaps the maximum tissue culture research has been done in citrus during the past four decades, however, the results of practical value are meagre. The shortfalls in citrus tissue culture research and some advancements made in this direction along with bright prospects are highlighted, restricting the review to vegetative explants only. Whilst utilization of nucellar embryogenesis is limited to rootstocks, the other aspects, like, regeneration and proliferation of shoot meristems measuring 200 microm in length--a global breakthrough--of two commercially important scion species, Citrus aurantifolia and C. sinensis and an important rootstock, C. limonia, improvement of micrografting technique, cloning of the same two scion species as well as some Indian rootstock species, employing nodal stem segments of mature trees, of immense practical value have been elaborated. A rare phenomenon of shift in the morphogenetic pattern of differentiation from shoot bud differentiation to embryoid formation occurred during the long-term culture of stem callus of C. grandis. Stem callus-regenerated plants of C. aurantifolia, C. sinensis and C. grandis showed variation in their ploidy levels and a somaclonal variant of C. sinensis, which produced seedless fruits was isolated. Tailoring of rooting in microshoots to a tap root-like system by changing the inorganic salt composition of the rooting medium, resulting in 100% transplant success, and germplasm preservation through normal growth culture of shoots of C grandis without loss of regeneration capacity during 31 years, observed so far, are some other significant results. Plants of C. aurantifolia and C. sinensis raised from shoot meristem and micrografting were grown in a nethouse and those from nodal stem segments in the field along with the in vitro-raised plants of rootstocks, namely, C. jambhiri, C. karna and C. limonia. All the plants showed normal healthy growth. Significantly enough, the meristem regenerated plants of C. aurantifolia attained the reproductive phase just in 1 year of transplantation to soil similar to those raised from nodal stem segments of mature trees, which also produced normal fruits in the subsequent year while growing under field conditions. Thus, a significant fundamental concept of a maturity factor, carried over through as small a shoot meristem as 200 microm in length to cloned plants has been demonstrated. The concept is of far-reaching significance in citrus industry besides production of pathogen-free orchards.

Three-year follow-up after intracoronary gamma radiation therapy for in-stent restenosis. Original WRIST. Washington Radiation for In-Stent Restenosis Trial

BACKGROUND

The Washington Radiation for In-Stent Restenosis Trial (WRIST) is a double-blinded randomized study evaluating the effects of intracoronary radiation therapy (IRT) in patients with in-stent restenosis (ISR).

METHODS

One hundred and thirty patients with ISR (100 native coronary and 30 vein grafts) underwent PTCA, laser ablation, rotational atherectomy, and/or additional stenting (36% of lesions). Patients were randomized to either Iridium-192 IRT or placebo, with a prescribed dose of 15 Gy to a 2-mm radial distance from the center of the source.

RESULTS

Angiographic restenosis (27% vs. 56%, P=.002) and target vessel revascularization (TVR; 26% vs. 66%, P<.001) were dramatically reduced at 6 months in IRT patients. Between 6 and 36 months, IRT compared to placebo patients had more target lesion revascularization (TLR; IRT=17% vs. placebo=2%, P=.002) and TVR (IRT=17% vs. placebo=3%, P=.009). At 3 years, the major adverse cardiac event (MACE) rate was significantly reduced with IRT (39% vs. 65%, P=.003).

CONCLUSIONS

In WRIST, patients with ISR treated with IRT using 192Ir had a marked reduction in the need for repeat target lesion and vessel revascularization at 6 months, with the clinical benefit maintained at 3 years.

Effects of 2-deoxy-D-glucose on DNA repair and mutagenesis in UV-irradiated yeast

We have studied the effects of 2-deoxy-D-Glucose (2-DG) on the recovery of potentially lethal damage (PLDR), repair of chromosomal DNA, cyclobutane pyrimidine dimers (CPDs), reverse mutation and gene-conversion in UVC (254 nm) irradiated yeast. As studied by pulsed-field gel electrophoresis, post-irradiation chromosomal DNA repair kinetics in a phosphate buffer (PB) with 10 mM glucose (G) was biphasic, where the first phase exhibited a decrease and the second phase showed an increase in the band intensities. A post-irradiation treatment in PB + G (10 mM) with 2-DG (10, 20, 50 mM) reduced the decrease in the DNA band intensities in the first phase of DNA repair. As compared to a post-irradiation (125 J/m2) treatment in PB + G (10 mM), a treatment in PB + G (10 mM) + 2-DG (10 mM) showed a decreased PLDR, but increased revertants and gene-convertants.

Behavioural responses of lion-tailed macaques (Macaca silenus) to a changing habitat in a tropical rain forest fragment in the Western Ghats, India

This study reports critical changes in the behaviour patterns of lion-tailed macaques (Macaca silenus) inhabiting a continuously changing and deteriorating rain forest fragment in the Western Ghats, India. The study area, a privately owned rain forest patch in a tea/coffee garden called Puthuthotam, has suffered two massive selective logging episodes. Over the years, the native rain forest trees have been largely replaced by non-native/pioneer species resulting in loss of canopy contiguity and significant changes in other vegetation parameters. The almost wholly arboreal lion-tailed macaque now spends a considerable amount of time on the ground in this area. The species has also experienced a major shift in its diet, ranging patterns and other activities.

External biliary fistula

A biliary fistula is almost invariably related to gallstone disease and commonly follows a hurried cholecystectomy by an inexperienced surgeon. This catastrophy which is largely preventable, often necessitates repeated surgical intervention and accrues an estimated 5-year mortality rate approaching 30%. Published series only show a slight increase in the incidence (one per 150-200) after laparoscopic cholecystectomy. The injury results from imprecise dissection and inadequate demonstration of the anatomical structures. The diagnosis is usually obvious and persistent tachycardia and hypotension inspite of an adequate intravenous infusion and a normal central venous pressure is another well known indicator of subhepatic collection of bile, which indicates an urgent ultrasonographic scanning of the upper abodmen. ERCP is a useful diagnostic and therapeutic tool when the continuity of the extra-hepatic biliary system has not been disrupted. An endobiliary stent can be placed across the defect in the same sitting, to tide over the immediate crisis and perhaps treat the patient on a permanent basis. Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive technique of outlining both the intra and extrahepatic biliary tree, which can provide a better road map of the fistula than an ERCP. The management has to be tailored to the patient's condition and the expertise available. A bilio-enteric anastomosis, performed 4 to 6 months after the initial surgery on a dilated common hepatic duct is more likely to succeed than an operation on a septic, hypoproteinemic patient with sodden, friable, non-dilated bile ducts. On the other hand, waiting for the ducts to dilate in a patient with a complete transection of the bile ducts with complete biliary diversion only leads to depletion of the bile acid pool, severe electrolyte derangement and nutritional failure, leading on to sepsis and death.

Diabetes mellitus is associated with a decrease in vasoactive intestinal polypeptide content of gastrointestinal tract of rat

Vasoactive intestinal polypeptide (VIP) is an inhibitory non-adrenergic, non-cholinergic transmitter, which mediate in the relaxation of sphincters of the gastrointestinal tract. The aim of this study was to determine whether there is a change in the pattern of innervation and tissue content of VIP in the rat gastroduodenum after the onset of streptozotocin (STZ)-induced diabetes mellitus. Diabetes was induced by a single intraperitoneal injection of STZ (60 mg Kg(-1)). Four weeks after the induction of diabetes mellitus, the rats were anaethetised and the pancreata were removed for further processing. VIP was localized and measured in normal and diabetic rat gastroduodenal tissues by immunohistochemistry and radioimmunoassay, respectively. VIP immunoreactivity was stronger in the ganglion cells of the submucosal and myenteric plexuses of the gastric antrum and duodenum of normal rats (n = 6) when compared to that of diabetic rats (n = 6). Moreover, the number of VIP-positive neurons was significantly lower in the gastrointestinal tract of diabetic rats compared to normal. The VIP content of the gastric antrum and duodenum of diabetic rat was significantly lower (p< 0.05) than that of normal rat. In contrast to the lower tissue levels of VIP in the gastroduodenal segment of diabetic rats, the plasma level of VIP was significantly higher (p< 0.04) in diabetic rat compared to normal. The plasma level of VIP in normal rats was comparable to that measured in normal human beings. A low tissue level of VIP in the gastroduodenal tract of diabetic rat may contribute in part to the abnormal gut motility observed in diabetic patients.

Ventricular septal defect and multiple aneurysms

A 41-year-old man with a small perimembranous ventricular septal defect (VSD) developed aneurysms and aortic elongation, tortuosity and dissecting aneurysm. The asymptomatic VSD, without pulmonary circulatory disturbance, was considered hemodynamically benign and too small to warrant surgical closure. However, prolonged strenuous sporting activities could have potentiated premature development of aortic sclerosis and the unusual vascular lesions secondary to the VSD, and an injury may have precipitated mural dissection in the vulnerable aortic wall. Clinicopathological analysis of the unusual complications associated with the VSD suggests that closure of the defect at an early age should be considered to possibly obviate premature degenerative, valvular and vascular changes in adulthood and also secondary endocardial infection.

Agenesis of the skull bones

Agenesis of the cranial bones, a rare condition usually incompatible with life, was seen in a neonate. Embryogenesis and management of the condition are discussed. The defect heals with conservative treatment.

Class I major histocompatibility complex anchor substitutions alter the conformation of T cell receptor contacts

An immunogenic peptide (GP2) derived from HER-2/neu binds to HLA-A2.1 very poorly. Some altered-peptide ligands (APL) of GP2 have increased binding affinity and generate improved cytotoxic T lymphocyte recognition of GP2-presenting tumor cells, but most do not. Increases in binding affinity of single-substitution APL are not additive in double-substitution APL. A common first assumption about peptide binding to class I major histocompatibility complex is that each residue binds independently. In addition, immunologists interested in immunotherapy frequently assume that anchor substitutions do not affect T cell receptor contact residues. However, the crystal structures of two GP2 APL show that the central residues change position depending on the identity of the anchor residue(s). Thus, it is clear that subtle changes in the identity of anchor residues may have significant effects on the positions of the T cell receptor contact residues.

Three-dimensional structure of a new form of mare lactoferrin in 70% PEG 400 at 3.8 A resolution

Three-dimensional (3D) structure of a new form of diferric mare lactoferrin has been determined at 3.8 A resolution. The protein was crystallized in a space group P2(1)2(1)2(1) with a = 80.1 A, b = 103.7 A, c = 112.2 A with a solvent content of 57%. The structure was solved by molecular replacement method using the model of native mare lactoferrin. The structure has been refined using X-PLOR to a final R-factor of 22.6% for all the data in 15.0-3.8 A resolution range. The final refined model comprises 5281 protein atoms, 2Fe3+ and 2CO3(2-) ions. The protein folds into two globular N- and C-lobes. The two lobes are further divided into two domains N1, N2 in the N-lobe and C1, C2 in the C-lobe. The overall folding of the protein is similar to that observed for the native protein. The superposition of Calpha traces of native mare lactoferrin and the present structure gives an r.m.s shift of 0.7 A. There is a slight variation in the orientation of two lobes but the domain orientations in the present structure are identical to those observed in the native mare lactoferrin.

Compartment syndrome of the foot in a child

We report a case of a 12-year-old boy with acute compartment syndrome of the foot following a road-traffic accident. Due to the rarity of the injury, there was a delay in diagnosing the injury. An emergency fasciotomy was performed 19 hours after the injury. The foot healed with a mild extension contracture of the second toe.

A simple bacterial turbidometric method for detection of S. aureus

A simple and rapid turbidometric method based on specificity of lysosotaphin to lyse S. aureus exclusively has been developed for detection of S. aureus contamination in foods.

Chromium(III)-induced structural changes and self-assembly of collagen

Rat tail tendon (RTT) collagen has been reacted with a homologous series of chromium(III) complexes viz., (H2O)(4)Cr(OH)(2)Cr(H2O)(4+)(4) 1 (dimer), Cr(3)(OH)(4)(H2O)(5+)(9) 2 (trimer), and Cr(4)(OH)(4)(O2)(H2O)(4+)(12) 3 (tetramer), and the structural alterations brought about by these complexes have been investigated through atomic force microscopy (AFM) and circular dichroism (CD) studies. Examination of Cr(III)-treated tendons using AFM revealed changes in the D-periodicity of collagen, which may arise due to differences in the topological distribution of various Cr(III) complexes. Evidence for organisation of monomeric collagen into quarter staggered fibrils in the presence of Cr(III) dimer, 1, has been obtained. The quaternary structural changes induced by chromium in the protein have been correlated to the conformational changes of collagen in the absence of denaturation.

Reassessing hemodialysis adequacy in children: the case for more

Several lines of evidence support an upward revision in pediatric hemodialysis dose guidelines: Although current recommendations are derived largely from studies of dialysis mortality and morbidity in adults, recent reports of improved growth and pubertal development with more intensive dialysis highlight the need for appropriate pediatric outcome measures in the assessment of dialysis adequacy, particularly in prepubertal patients. Even if adult studies can be extrapolated directly to younger patients, reappraisal of these data would appear to justify an increase in recommended dialysis clearances, based on higher dietary protein intake and accumulating evidence that adults, too, benefit from more intensive therapy. Suboptimal dialysis may also occur when dialysis dose is overestimated by urea kinetic models that fail to account for compartment effects and post-treatment urea rebound. Studies comparing the available models in pediatric patients have appeared recently, and a few models have been developed specifically for pediatric applications. These should permit more reliable estimates of solute clearance for a much-needed multicenter trial to clarify optimal dialysis therapy for growing children.

Effect of alpha-tocopherol supplementation on the ultrastructural abnormalities of peripheral nerves in experimental diabetes

Ultrastructural observations were made on myelinated fibers in the tibial nerves in order to investigate the beneficial effects of alpha-tocopherol administration in streptozotocin-diabetic rats. Male Wistar rats, aged 12 weeks and weighing between 250 g to 300 g were studied. Six onset control rats were used to obtain the baseline parameters for this strain and age. Further 3 groups--untreated diabetic animals, diabetic animals treated with alpha-tocopherol, and age-matched controls--were studied over a 3-month period. In the diabetic animal, administration of alpha-tocopherol resulted in a significant increase (p < 0.05) in total plasma vitamin E levels when compared with other groups. Myelinated fiber cross-sectional area (p < 0.05), axonal area (p < 0.01) and myelin sheath area (p < 0.05) were significantly less in the tibial nerve of diabetic animals than in age-matched controls, but not different from those of onset controls. In the alpha-tocopherol treated diabetic animals, the values for these parameters were intermediate without showing significant difference when compared with age-matched controls and untreated diabetics. The "g" ratio (axon to fiber area) did not differ between any experimental groups. The number of large myelinated fibers were less in the untreated diabetic animals, but in the alpha-tocopherol-treated diabetics, the values were significantly higher (p < 0.05) than with untreated diabetics and were similar to those of age-matched controls. In conclusion, this ultrastructural study reiterated the fact that structural abnormalities of myelinated fibers occur in experimental diabetes and that alpha-tocopherol administration may be useful in preventing the development of these abnormalities.

Benzyl ester prodrug of ibuprofen: pharmacological and toxicological profile

Prodrug approach is a promising way of overcoming gastrotoxicity associated with long term oral use of NSAIDs like ibuprofen. The candidature of benzyl ester prodrug of ibuprofen was examined to assess its ability to reduce gastrotoxicity without affecting pharmacological response. It gave highly promising activity profile in established animal models like carrageenan induced rat paw oedema and acetic acid induced writhing reflex assay. The effect of physicochemical properties like aqueous solubility, octanol-water partition coefficient, hydrolysis kinetics in human plasma and simulated gastric fluid, on activity profile has been investigated.