Cutting balloon angioplasty for aortic coarctation

BACKGROUND

Cutting balloon angioplasty (CBA) has improved outcomes for resistant stenotic vascular lesions in adult coronary artery disease. Application of this technique in coarctation of the aorta (CoA) in children has not been reported.

OBJECTIVE

We sought to review the safety, efficacy and outcomes of CBA in the setting of CoA.

METHODS AND RESULTS

Between February 2004 and October 2007, 8 children (4 males) underwent 10 procedures. The median age was 5.5 months (range: 2.5 months to 5 years) and median weight 7.5 kg (range: 4.1-13.3 kg). Two children had native CoA. CBA was employed due to a persistent waist after conventional balloon angioplasty (6 procedures) or as the primary dilatation (4 procedures). The cutting balloon diameter was a median 143% (range: 108-222%) of the diameter of the lesion. After dilatation, all children underwent further conventional balloon angioplasty. The CoA median diameter increased from 2.8 mm (range: 1.8-4 mm) to 4 mm (range: 2.9-6.7 mm; p = 0.0018), and the arm-to-leg blood systolic blood pressure gradient decreased from 38.5 mmHg (range: 2-70 mmHg) to 7 mmHg (0-30 mmHg; p < 0.0001). The median follow-up period was 4.6 months (range: 0.5-15.6 months), and 2 children required a second balloon dilatation. No aneurysm formation was observed acutely, although 2 children each developed a femoral arteriovenous fistula or a pseudoaneurysm.

CONCLUSION

This early experience suggests that CBA is acutely safe and can be effective in the management of recalcitrant coarctation lesions in the young.

On multiscale approaches to three-dimensional modelling of morphogenesis

In this paper we present the foundation of a unified, object-oriented, three-dimensional biomodelling environment, which allows us to integrate multiple submodels at scales from subcellular to those of tissues and organs. Our current implementation combines a modified discrete model from statistical mechanics, the Cellular Potts Model, with a continuum reaction-diffusion model and a state automaton with well-defined conditions for cell differentiation transitions to model genetic regulation. This environment allows us to rapidly and compactly create computational models of a class of complex-developmental phenomena. To illustrate model development, we simulate a simplified version of the formation of the skeletal pattern in a growing embryonic vertebrate limb.

A study of sutopsy findings in 62 cases of leptospirosis in a metropolitan city in India

BACKGROUND

Leptospirosis is an important sporadic zoonotic disease caused by the spirochete Leptospira icterohaemorrhagiae . The disease becomes a major public health problem, particularly during the monsoon months.

MATERIALS AND METHODS

Analysis of autopsy findings of 62 cases of clinically suspected leptospirosis was carried out to identify the pathology and determine the cause of death.

RESULTS

Most patients were young males who presented with fever, breathlessness, haemoptysis, bleeding, oliguria and icterus. They died after a brief stay in hospital. A post-mortem diagnosis of leptospirosis was made on the basis of characteristic organ findings, aided by results of serology, Levaditi's staining and / or immunohistochemistry (IHC) on kidney sections. Massive intra-alveolar haemorrhage (48 cases), acute interstitial nephritis and / or acute tubular necrosis (45 cases) and myocarditis (24 cases) were the main autopsy findings. Haemorrhage in various organs like the heart, gastrointestinal tract, brain, pancreas and adrenals were also seen. Thirty of 54 kidney sections were positive for leptospiral antigens by IHC. There was extensive haemorrhages in the lungs in 48 (77%) cases and that was the cause of death in most of these cases.

CONCLUSION

Bleeding into various tissues and organs is the main finding noted in this study. The post-mortem examination of patients dying of leptospirosis revealed that pulmonary haemorrhage was the cause of death in most individuals.

In vitro morphogenesis in zygotic embryo cultures of neem (Azadirachta indica A. Juss.)

Immature zygotic embryo cultures of neem yielded highly regenerative cultures, with the response varying with the embryo stage at culture. Early dicotyledonous stage embryos were the most responsive followed by torpedo stage embryos. The embryo cultures differentiated three types of regenerants: somatic embryos (SEs), shoot buds and neomorphs. SEs exhibited morphological abnormalities such as pluricotyledony, fusion of cotyledons and absence of cotyledons. Although these SEs showed secondary embryogenesis, the occurrence of normal dicotyledonous embryos was extremely rare. On MS basal medium 3% of SEs developed a long tap root but a plumular shoot did not appear. However, it was possible to regenerate plantlets from immature zygotic embryo cultures of neem via neomorph formation and adventitious shoot bud formation. The transplantation survival of these plants was more than 80%.

COMPUCELL, a multi-model framework for simulation of morphogenesis

MOTIVATION

CompuCell is a multi-model software framework for simulation of the development of multicellular organisms known as morphogenesis. It models the interaction of the gene regulatory network with generic cellular mechanisms, such as cell adhesion, division, haptotaxis and chemotaxis. A combination of a state automaton with stochastic local rules and a set of differential equations, including subcellular ordinary differential equations and extracellular reaction-diffusion partial differential equations, model gene regulation. This automaton in turn controls the differentiation of the cells, and cell-cell and cell-extracellular matrix interactions that give rise to cell rearrangements and pattern formation, e.g. mesenchymal condensation. The cellular Potts model, a stochastic model that accurately reproduces cell movement and rearrangement, models cell dynamics. All these models couple in a controllable way, resulting in a powerful and flexible computational environment for morphogenesis, which allows for simultaneous incorporation of growth and spatial patterning.

RESULTS

We use CompuCell to simulate the formation of the skeletal architecture in the avian limb bud.

AVAILABILITY

Binaries and source code for Microsoft Windows, Linux and Solaris are available for download from http://sourceforge.net/projects/compucell/

Production of haploids of neem (Azadirachta indica A. Juss.) by anther culture

Androgenic haploids of the neem tree (Azadirachta indica A. Juss.) were produced by anther culture at the early- to late-uninucleate stage of pollen. Haploid formation occurred via callusing. The best medium for inducing callusing in the anther cultures was Murashige and Skoog's basal medium (MS) (9% sucrose) supplemented with 1 microM 2,4-D, 1 microM NAA and 5 microM BAP, while anther callus multiplied best on MS medium supplemented with 1 microM 2,4-D and 10 microM Kn. These calli differentiated shoots when transferred to a medium containing BAP; 5 microM BAP was optimum for young calli (75% cultures differentiated shoots), but older calli showed the best regeneration with 7.5 microM BAP. Shoots elongated at a lower concentration of BAP-0.5 microM. These shoots were multiplied by forced axillary branching and rooted in vitro. The plants were subsequently established in soil. Of the plants that regenerated from anther callus 60% were haploid, 20% were diploid and 20% were aneuploid.

Alagille syndrome

Syndromic paucity of bile ducts or "Alagille syndrome" is characterized by peculiar facies, chronic cholestasis, posterior embryotoxon, butterfly-like vertebral arch defects and peripheral pulmonary artery hypoplasia or stenosis. We present a two-year-old female child with the 'partial' or 'incomplete' Alagille syndrome. The child had three of the five major features of the syndrome. A brief review of literature of the syndrome is presented.

Estrogen receptors in rat bone: their interaction with estrogen receptor modulators

Estrogen receptors (ER) were studied in rat bone cytosol using immunoprecipitation, and Western blot technique. Ligand specificity of bone ER was studied using various known modulators of ER. Competitive experiments were performed under exchange conditions in bone tissue obtained from one day old rats. ER alpha and beta subtypes were identified using immunoblotting experiments compared with that of ovarian and uterine tissues. In competitive binding assay, maximum inhibition in specific 3H-E2 binding was shown by E2 followed by tamoxifen and diethylstilbestrol. 7-Hydroxycentchroman and 85/287 also inhibited specific 3H-E2 binding but were less potent as compared to tamoxifen and diethylstilbestrol. However, 85/287 was less effective (81%) as compared to 7-hydroxycentchroman. Polyacrylamide gel electrophoresis of cytosol and Western blot analysis revealed the presence of 55 kD and 66 kD ER immunoreactive bands corresponding to alpha and beta subtypes, respectively, in bone as well as in uterus. Interestingly, the concentration of 55 kD ER was 3-fold higher than that of 66 kD ER. Ovarian cytosol revealed the presence of a 55 kD band only in Western blot analysis. These studies suggest the action of estrogens/ER modulators on osteoblasts which contain a limited number of classical alpha as well as beta sub types of ER that are known to be structurally different in their hormone-binding domains.

Cranial irradiation--an unusual cause for diabetes insipidus

Central diabetes insipidus frequently occurs due to tumours in the region of pituitary or hypothalamus or following surgical trauma to these regions. Rarely it has been reported following cranial irradiation. We report the case of a middle aged woman who underwent surgical removal of a frontal capillary hemangioblastoma and received cranial irradiation. She presented ten months later with features of diabetes insipidus which was confirmed to be of central origin. She responded well to desmopressin nasal spray. Radiation induced damage to the hypothalmo-pituitary axis presents usually with anterior pituitary hormone deficiencies, most commonly that of growth hormone. Presentation as central diabetes insipidus is very uncommon.

The delta-endotoxin proteins accumulate in Escherichia coli as a protein-DNA complex that can be dissociated by hydrophobic interaction chromatography

The insecticidal protein CryIAc accumulated to form inclusion bodies in Escherichia coli upon overexpression of the cloned gene. The solubilized inclusion bodies contained the delta-endotoxin in association with DNA fragments of about 25 kb. The protein-DNA complex could be dissociated and the delta-endotoxin purified by hydrophobic interaction chromatography on phenyl-Sepharose. The DNA was washed out in the high-salt buffer while the delta-endotoxin was bound to the matrix and was eluted at 4 degrees C by a stepwise decreasing potassium chloride gradient. The DNA-protein complex also contained plasmids harbored by the host strain. The plasmid DNA associated with the complex became competent to transform E. coli only after it was dissociated from the delta-endotoxin. The hydrophobic interaction chromatography provides an efficient method for the purification of DNA-free activated toxin.

Effect of light intensity on in vitro multiple shoot induction and regeneration of cotton (Gossypium hirsutum L. cv Khandawa-2)

Cotyledonary nodes taken alongwith shoot apex from seedlings of cotton (G. hirsutum) proliferated into shoots on nutrient agar medium supplemented with cytokinins. In the presence of optimal plant growth regulators, low light intensity enhanced the number of shoots initiated per explant in cotton. An average of 33.5 +/- 2.9 shoots were obtained from a single explant cultured for 8 weeks which is about four fold higher than the values reported in earlier protocols. The isolated shoots were rooted on nutrient agar medium supplemented with alpha-naphthalene acetic acid and transferred to soil after acclimatization. Regenerated plants were morphologically identical to the seed-germinated plants and were fertile.

Degradation and de novo synthesis of D1 protein and psbA transcript levels in Chlamydomonas reinhardtii during UV-B inactivation of photosynthesis and its reactivation

UV-B induces intensity and time dependent inhibition of photosynthetic O2 evolution and PS II electron transport activity in Chlamydomonas reinhardtii. The D1 and D2 proteins of chloroplast membranes are rapidly and specifically degraded in the course of irradiation of cells to UV-B. Continuous synthesis of the two proteins was essential for the repair of damaged PS II as chloramphenicol accelerated UV-B inactivation of photosynthesis and prevented photoreactivation. Northern analysis revealed that UV-B also affected the expression of psbA gene coding for the D1 protein. Cells showing 72% inhibition of PS II activity, revealed a modest net loss of 25% in the level of D1 protein. This shows that synthesis of D1 protein is not the only component involved in the recovery process. Our results indicate that besides affecting the synthesis of the D1 protein UV-B may impair certain post-translational events, which in turn may limit the repair of damaged PS II.

Antioxidant protection against iron toxicity: plasma changes during cardiopulmonary bypass in neonates, infants, and children

Cardiopulmonary bypass surgery is associated with the release of low molecular mass iron, which increases the saturation of plasma transferrin to over 50% in all adult patients treated. In a significant minority, however plasma transferrin becomes 100% iron saturated and non-transferrin bound iron can be detected in the plasma. An iron-saturated transferrin is also a common physiological finding in normal term and pre-term infants at a time when their plasma antioxidants, which protect against iron toxicity and radical scavenging, are profoundly different from those seen in adults. This study was conducted to assess the extent to which antioxidants, which protect against iron toxicity, are altered in neonates, infants, and children undergoing cardiopulmonary bypass surgery.