Double patch closure of ventricular septal defect with increased pulmonary vascular resistance

BACKGROUND: Closure of a large ventricular septal defect (VSD) in children with elevated pulmonary vascular resistance is associated with significant morbidity and mortality. Pulmonary hypertensive episodes continue to be a major cause of postoperative morbidity and mortality. We designed a fenestrated flap valve double VSD patch in an effort to decrease the morbidity and mortality associated with the closure of a large VSD with elevated pulmonary vascular resistance. METHODS: Eighteen children (mean age, 5.7 years) with a large VSD and elevated pulmonary vascular resistance (mean, 11.4 Wood units) underwent double patch VSD closure using moderately hypothermic cardiopulmonary bypass and cardioplegic arrest. The routine VSD patch was fenestrated (4 to 6 mm) and on the left ventricular side of the patch, a second, smaller patch was attached to the fenestration along its superior margin before closure of the VSD. RESULTS: All children survived operation and were weaned from inotropic and ventilator support within 48 hours postoperatively. Postoperative pulmonary artery pressures were significantly lower than preoperative values. One child died 9 months postoperatively. CONCLUSIONS: Closure of a large VSD in children with elevated pulmonary vascular resistance can be performed with low morbidity and mortality when a flap valve double VSD patch is used.     

Short-term results of scleral intraocular lens fixation in children

PURPOSE: To study the safety and efficacy of scleral intraocular lens (IOL) fixation in children. SETTING: A university practice. METHODS: This retrospective review evaluated the results and complications in 6 consecutive eyes of 3 children who had anterior vitrectomy, with or without lensectomy, and scleral IOL fixation to correct ectopia lentis or aphakia. RESULTS: At a mean follow-up of 17.3 months (range 13 to 21 months), all eyes had a stable and well-positioned posterior chamber IOL and good visual improvement. The only complication was asymptomatic pupillary capture of the IOL in 3 eyes. Reversal of the pupillary capture was achieved by pupil dilation with the patient in a supine position. CONCLUSIONS: The preliminary results of scleral IOL fixation in children are encouraging. The procedure's application in well-selected cases can be considered. However, its long-term safety and efficacy must be further assessed through studies with larger sample sizes and a longer follow-up.     

Nonsurgical infarctectomy in acute experimental myocardial infarction

This study examines whether a catheter mounted left intraventricular balloon may prevent left ventricular (LV) dysfunction following acute experimental myocardial infarction. In 10 anesthetized pigs, multiple coronary arterial ligations were applied around the apex of the heart. LV end-diastolic pressure (LVEDP), aortic flow (AF), and LV long and short axis fractional shortening (FS) were measured before and at 15 min intervals after ligations. At the 60th min after ligation, the LV long axis FS and AF decreased by 7.2 +/- 2.6% (p < 0.05) and 13.25 +/- 2.68% (p < 0.01), respectively, and the LVEDP increased by 4.3 +/- 1.1 mm Hg (p < 0.01) while no change was noted in the LV short axis FS. An intraventricular catheter mounted nonpulsating balloon was positioned over the endocardium of the infarcted area at the LV apex. Inflation of the nonpulsating balloon to an optimal volume, which was found to be equal to 8-10% of the LV end-diastolic volume, resulted in a reduction (by 3.8 +/- 1.2 mm Hg, p < 0.01) of the already increased LVEDP and in an increase (by 6.6 +/- 2.1%, p < 0.05) in the LV short axis FS while no statistically significant change was noted in the AF and LV long axis FS. It is concluded that an intraventricular catheter mounted balloon patch positioned over the endocardium of the infarcted area may ameliorate early LV dysfunction, possibly by interfering with the functional geometry of the LV contraction.     

Phospholipid pool, lipid peroxidation, and superoxide dismutase activity under various types of oxidative stress of the brain and the effect of low-energy infrared laser irradiation

The effect of low-energy infrared laser irradiation on the phospholipid pool, lipid peroxidation, and superoxide dismutase activity in the brain of white rats was studied in experimental ischemia, reperfusion, and acute edema. These models are characterized by oxidative stress; the contents of tri- and diphosphoinositides and sphingomyelins were lowered, whereas the levels of phosphatidylserine and phosphatidylethanolamine did not change, and the amount of phosphatidylcholine was increased. In acute brain edema, the contents of hydroperoxides and malonic dialdehyde in enzymatic and nonenzymic lipid peroxidation systems were increased in mitochondrial and microsomal fractions and the level of arachidonic acid was significantly elevated. Infrared laser irradiation contributes to the correction of the changes in the phospholipid pool; laser irradiation lowered the increased levels of hydroperoxides and malonic dialdehyde and elevated superoxide dismutase activity in the brain during ischemia, reperfusion, and acute edema of the brain. The data suggest that low-energy infrared laser irradiation has certain neuroprotective activity in various types of oxidative stress including ischemia, reperfusion, and acute edema of the brain.     

Receptors for calcitonin gene-related peptide (CGRP) in the rat adrenal cortex

We previously demonstrated the presence of adrenomedullin receptors in the rat adrenal cortex. There is evidence, however, that the actions of adrenomedullin may also be mediated by the CGRP receptor. The present study was designed to determine whether specific CGRP receptors are present in the rat adrenal cortex. Adrenal glands were, sectioned and immunostained with a primary antibody raised against the first intracellular loop of the CGRP-I receptor. Staining was visualised using alkaline phosphatase and vector red. Immunostaining for the CGRP-I receptor was found in the zona glomerulosa and the adrenal medulla, but not in the inner adrenocortical zones. ACTH treatment caused an increase in staining intensity in the glomerulosa. Ligand binding studies suggested the existence of two populations of CGRP binding sites, one with a Kd of 0.1 nM, the second of 37 nM. Only CGRP-I and adrenomedullin displaced labeled CGRP binding. These results suggest that the CGRP-I receptor is expressed in the adrenal zona glomerulosa and that a second class of binding site is also present. The CGRP-I receptor appears to be regulated by ACTH.     

Enteropathogenicity markers in Escherichia coli isolated from infants with acute diarrhoea and healthy controls in Rio de Janeiro, Brazil

Faeces from urban children < 2 years old with acute diarrhoeal illness and from non-diarrhoeal infants (controls) were examined for Escherichia coli and other enteropathogens. A total of 990 E. coli isolates from 100 patients and 50 controls was tested for enteropathogenic E. coli (EPEC) serotype (O:H), adherence to HEp-2 cells after incubation for 3 and 6 h, fluorescent actin staining (FAS), DNA hybridisation with EAF, eaeA, STh, STp and EAggEC probes and production of heat-labile enterotoxin (LT) and verocytotoxin (VT) with Y1 and Vero cells. EPEC were the most prevalent enteropathogens in patients (32.7%; and 14% in controls). Enteroinvasive E. coli (EIEC) and Vero cytotoxin-producing E. coli (VTEC) were not detected. The rate of isolation of enterotoxigenic E. coli (ETEC) was identical in both groups. Among the EPEC isolates the prevalent serotypes were O111:H2, O55:NM and O119:H6. Localised adherence (LA) was found significantly more frequently in isolates from patients (19.6%) than controls (2.1%). All LA-positive EPEC isolates were FAS+ and eaeA+, but only 75.2% of them hybridised with the EAF probe. Diffusely adhering E. coli (DAEC) and enteroaggregative E. coli (EAggEC) were found with equal frequency in patients and controls. Twenty-seven E. coli isolates were negative for EAF but positive for eaeA and FAS and produced LA in 6-h adherence tests. These EAF-/eaeA+ strains were the only putative enteropathogen identified in seven patients and were not found in controls. The ability of these strains to elicit ultrastructural cell alterations and cell-signalling events was evaluated in Caco-2 cells (human colon carcinoma cell line) by the gentamicin invasion assay and by transmission electron microscopy. The numbers of intracellular bacteria in cell invasion tests varied from 0.4% to 1.6% of the cell-associated bacteria after a 6-h incubation period. Tyrosine phosphorylation of host cell proteins was assessed in HEp-2 cells by immunofluorescence microscopy and all strains gave positive results. EAF-/eaeA+ E. coli strains express most of the virulence properties found among true EPEC strains and can be a relevant cause of infant diarrhoea in developing countries.     

Mutations in the glucokinase gene of the fetus result in reduced birth weight

Human papillomavirus (HPV) type 60 infection is histologically associated with characteristic homogeneous intracytoplasmic inclusion bodies. However, it remains unclear whether the virus is associated with cystic, pigmented or ridged plantar warts. We report a 51-year-old Japanese female with a HPV-60-induced plantar wart which showed the clinical appearance of both pigmented and ridged warts. Masson-Fontana staining revealed increased melanin granules in the epidermis of the wart. This observation suggests that HPV-60 may be associated not only with cystic warts but also with the specific morphology of ridged warts, and the biological disorder of hyperpigmentation may be controlled by additional unknown factors which differ from case to case.     

Transgenic models in renal tubular physiology

Animal transgenesis has proven to be useful for physiological as well as physiopathological studies. Besides the classical approach based on the random integration of a DNA construct in the mouse genome, gene targeting can be achieved using totipotent embryonic stem (ES) cells for targeted transgenesis. Transgenic mice are then derived from the transgenic ES cells. This allows the introduction of null mutations in the genome (so-called knock-out) or the control of the transgene expression by the endogenous regulatory sequences of the gene of interest (so-called knock-in). Development of these transgenic animals leads to a better understanding of the cellular function of many genes or to the generation of animal models for human diseases. The purpose of this short review is to describe animal models in renal tubular physiopathology. Recent progresses will allow the generation of animal models with conditional expression of the transgene of interest or with a conditional gene mutation. This permits spatial and temporal control of the expression of the transgene or of the mutation. This should allow the generation of models suitable for physiological analysis or closer to disease state.