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PubMed1999

[A case report of successful mitral valve replacement for congenital mitral stenosis associated with coarctation of the aorta and ventricular septal defect].

A 5-month-old infant with coarctation of the aorta, ventricular septal defect and mitral stenosis known as "Shone's anomaly" is presented. He underwent the repair of coarctation of the aorta by means of the extended aortic arch anastomosis and banding of the pulmonary trunk at 1 month of age and the patch closure of ventricular septal defect and debanding of the pulmonary trunk at 3 months of age in our institution. About 2 months after second surgery, he had been admitted to our institution due to developing tachypnea and he needed the support of mechanical ventilation. The chest X-ray showed pulmonary congestion and the echocardiography revealed only one papillary muscle of mitral valve and pressure gradient about 30 mmHg through mitral valve. Mitral stenosis due to parachute mitral valve was suspected and he was subjected to an emergent surgery. Initially we performed mitral valve repair for parachute mitral valve but echocardiography during the surgery revealed moderate grade of mitral regurgitation and a hemodynamics was not satisfactory. Eventually mitral valve replacement was successfully done with Carbo-Medics mechanical valve (19 mm in diameter) in the position of left atrial wall because his mitral annulus was so small as 10 mm in diameter. The postoperative course was uneventful and the patient has been doing well.

Aortic Coarctation↗
PubMed1999

[A new anatomical approach to congenital valve diseases by three-dimensional echocardiography].

Congenital valvular heart disease in childhood is often complex. Conventional echocardiography provides two-dimensional views which require mental reconstruction for three-dimensional assessment. This problem may be solved by the use of three-dimensional (3D) echocardiography which obtains images of valves comparable to those seen at surgery. This was confirmed by 4 cases of congenital valvular heart disease studied by 3D echocardiography: stenotic bicuspid aortic valve disease, parachute mitral valve and two cases of mitral regurgitation in patients with atrioventricular canal. The 3D views of the aortic valve showed the commissural opening after percutaneous balloon valvuloplasty of the bicuspid valve. The surface of the aortic orifice and the surface of the two mitral leaflets were measured from 3D reconstructions. The longitudinal 3D view analysed the extension of the single obstructive mitral papillary muscle of the parachute malformation. The 3D ventricular views allowed assessment of the extension of the cleft and the surface of the three mitral leaflets of the 2 cases of atrioventricular canal. In one of these cases, the results of surgical valvuloplasty were evaluated after 3D reconstruction of the valve. 3D echocardiography is not only a diagnostic tool for congenital heart disease but also a very useful complementary investigation for accurate evaluation of congenital valvular lesions to optimise possible valve repair.

Adolescent↗
PubMed1991

Spondylolysis and spondylolisthesis in military parachutists.

This paper reports on three cases of symptomatic low back pain in three paratroopers in association with bilateral L5 spondylolysis and L5 on S1 spondylolisthesis. The controversy regarding the etiology of this lesion as well as the problems of establishing causality when associated with parachuting injuries are discussed. These cases raise the issue of whether routine lumbar spine roentgenography should be performed as part of the pre-course medical screening prior to an individual undertaking basic parachutist training, and stress the need for further study of the relevance of these lesions in military parachuting.

Accidental Falls↗
PubMed1990

[Use of beta receptor blockers in performance sports].

The application of beta-blocking agents in endurance sports leads to deterioration of physical capacity because of negative influence of hemodynamics and metabolism. In sports with modest dynamic but high psychological strain it leads to an increase of physical capacity and decrease of stress caused by competition. The present paper summarizes changes in ski jumping, flying, motor car racing, parachute jumping, bob running and shooting. Significant decreases of heart rate, modest decreases in blood pressure as well as a reduction of occasionally appearing extrasystoles are found. Levels of glucose and lactate as well as cholesterol and triglycerides remain unchanged during beta-blockade, as do free fatty acids and free glycerol with placebo under beta-adrenolyse. Whereas ski and parachute jumpers display psychologic stress, bob runners and sport shooters were positively influenced. As a possible reason for an increased physical capacity after sympathicolysis, changes of cardiovascular parameters as well as central influences are conceivable. The application of beta-blocking agents should be regarded as "doping" because of the increases of physical capacity and should be avoided in healthy sportsmen.

Adrenergic beta-Antagonists↗
PubMed1990

[Mitral valve replacement in young children: a long-term follow-up].

The Authors report follow-up data (mean 60, range 13-101 months) from 4 patients under two years of age (mean 11.5 months) operated on for prosthetic mitral valve implantation. Two patients were male and two female. Pre-operative diagnosis was partial atrioventricular septal defect with parachute mitral valve in one case and isolated mitral valve anomaly in the others (1 parachute, 2 hammock valves). One bioprosthesis (Liotta n. 23) and three mechanical prostheses (Björk-Shiley) were implanted. Complications occurred in two patients: one case of endocarditis on the bioprosthesis, leading to substitution with a Björk-Shiley valve; one case of acute thrombosis 8 months after implantation in the only pt receiving aspirin as prophylactic therapy. This complication was resolved by intravenous thrombolytic agents. All the patients are alive, in I NYHA functional class and receiving oral anti-coagulants. Instrumental follow-up with eco-Doppler demonstrated normal functioning prostheses in all the patients. A sub-aortic gradient was found in the patient with partial atrioventricular septal defect. Prosthesis-patient mismatch was identified in a patient operated on when she was 6 months old who was followed-up for 5 years.

Bioprosthesis↗
PubMed1985

Physiological characteristics of elite sport parachutists.

The physiological characteristics of 10 male elite sport parachutists (31.6 +/- 3.69 years of age) were determined and compared to 10 male non-sport parachutist controls (30.2 +/- 4.31 years) and other selected elite athletes. The typical sport parachutist was a highly educated (16.4 +/- 2.41 years), first born (9 out of 10), and, more often than not, single individual. During their mean 10.8 years of sport parachuting, these individuals made an average total number of 1,950 jumps (range 980 to 3,100) with a mean of 237.5 jumps during each of the last three years. Mean total free fall time was 22 h and 40 min. Compared to the non-sport parachutist control group, the elite sport parachutists were significantly higher (p less than 0.05) in aerobic power (47.4 +/- 9.04 vs. 37.2 +/- 4.67 ml X kg-1 X min-1), vital capacity (5.27 +/- 0.49 vs. 5.05 +/- 0.31 L), maximum heart rate (203.2 +/- 9.2 vs. 190.1 +/- 7.4 bpm), and back hyperextension flexibility (21.12 +/- 4.1 vs. 18.41 +/- 2.4 in). The elite sport parachutist were also significantly lower (p less than 0.05) in relative (%) body fat when compared to the control group (15.7 +/- 4.51 vs. 20.1 +/- 2.12%). The two groups were not significantly different (p greater than 0.05) with respect to resting heart rate, absolute body weight, dominant hand-grip strength, or lower back/hamstring flexibility as measured by the sit-and-reach test. Regarding somatotype, the elite sport parachutist can be classified as a balanced mesomorph. Compared to other selected elite athletes, the sport parachutists were lower in aerobic power and higher in relative body fat, yet with a summation of triceps, suprailiac, and abdominal skinfolds in the acceptable range for male athletes. The elite sport parachutists were approximately mid-range in absolute body weight and lower back/hamstring flexibility when compared to other selected elite athletes. Based on the findings of this study, there is evidence to suggest that some form of regular aerobic exercise along with a stretching and flexibility program is advisable for those individuals considering frequent participation and desiring peak performance in sport parachuting.

Adult↗
PubMed1978

Permanent changes in the spines of military parachutists.

To investigate whether parachuting causes permanent changes in the spine, 50 military parachutists (mean number of jumps 490 per parachutist) and 50 matched controls were studied. In X-rays of parachutists and controls, the frequency of degenerative changes differed in the cervical spine (46 and 20%; p less than 0.01), and in the thoracic spine (62 and 28%; p less than 0.05) but not in the lumbar spine (44 to 36%; not significant). Parachutists suffered significantly more often from stiff neck, but the incidence of other neck and back symptoms was the same in the two groups. The increased frequency of degenerative changes in the spine in military parachutists is probably due to repeated traumata which parachutists sustain on landing and, possibly, during the training period before parachute jumps.

Adult↗
PubMed1993

Effects of psychological stress on plasma interleukins-1 beta and 6, C-reactive protein, tumour necrosis factor alpha, anti-diuretic hormone and serum cortisol.

The study was undertaken to determine whether psychological stress influences immunobiological functions and is an important preanalytical factor to be considered in connection with blood specimen collection. Two kinds of stress were applied, the Stroop colour conflict test and the thrill of a novice about to make the first jump with a parachute. In both test situations, the level of the stress indicators cortisol or anti-diuretic hormone rose significantly. The concentrations of the cytokines studied did not change significantly. However, in the parachute test significant positive correlations were found, e.g. between the changes of cortisol and C-reactive protein and between anti-diuretic hormone and interleukin-1 beta. This suggests that there is an interaction between the endocrine and the immune systems in the response to a psychological stress.

Adolescent↗
PubMed1997

Review of major injuries and fatalities in USAF ejections, 1981-1995.

Our laboratories are examining injuries and deaths resulting from mechanical forces applied to aircrew members in the course of Department of Defense aviation operations. In this paper we report only on bodily injuries sustained during ejection from US Air force, aircraft for the fiscal years 1981-1996, that is, major injuries and fatalities resulting directly from seat acceleration forces, from aerodynamic forces applied to crew members during escape through the effects of windblast and parachute opening shock; from direct contact: and from parachute landing injuries. Such injuries occur typically to the head, neck, cervical spine, thorax, thoracolumbar spine, ribs, pelvis, and the upper and lower extremities. Injuries are usually caused by anomalies in the ejection sequence or by delaying ejection until too close to the ground. Conversely, a planned ejection in a modern ejection seat in controlled, low speed flight imposes forces well below injury thresholds. In the USAF, 10-50 aircrew eject yearly, with a decline since 1991. We conclude that the risk of fatality is 0-11% and of major injury is 2-25%. Both are remarkably low and decreasing in the later years of this study period. The absolute number of head, neck, and spine injuries is 0-10 yearly and similarly decreasing. The results of this study are intended to provide a basis for estimating potential savings in deaths, injuries, and costs expected from the development of improved protective measures.

Accidents, Aviation↗
PubMed1987

Familial CHARGE syndrome: clinical report with autopsy findings.

We report on a patient with CHARGE syndrome, as manifested by a coloboma of the optic nerve head, congenital heart defect (ASD, VSD, and parachute mitral valve), choanal atresia, severe growth retardation, genital hypoplasia, abnormal ears, cleft lip and palate, and pectus carinatum. His chromosomes were normal. He died at 19 months. His mother was short and had hearing impairment, choanal atresia, and a coloboma. We suggest that this represents evidence for dominant transmission of this disorder in this family. Other familial cases from the literature are reviewed.

Abnormalities, Multiple↗
PubMed2003

N-cadherin is essential for retinal lamination in the zebrafish.

N-cadherin is one of the major Ca(2+)-dependent cell adhesion proteins in the developing nervous system. Here, we analyze eye development in the zebrafish N-cadherin loss-of-function mutant parachute(paR2.10) (pac(paR2.10)). The zebrafish visual system is fully developed by the time pac(paR2.10) mutants show lethality at day 5. Already at 24 hr postfertilization (hpf), mutant retinal cells are more disorganized and more rounded than in wild-type. At later stages, mutant retinae display a severe lamination defect with rosette formation (mostly islands of plexiform layer tissue surrounded by inner nuclear layer or photoreceptor cells), even though all major classes of cell types appear to be present as determined by histology. Of interest, electron microscopy reveals that the islands of plexiform layer tissue contain a normal amount of synapses with normal morphology. Although mutant photoreceptor cells are sometimes deformed, all typical structural components are present, including the membranous discs for rhodopsin storage. The lens fibers of the pac(paR2.10) mutants develop completely normally, but in some cases, lens epithelial cells round up and become multilayered. We conclude that cell adhesion mediated by N-cadherin is of major importance for retinal lamination and involved in maintenance of the lens epithelial sheet, but is not essential for the formation of photoreceptor ultrastructure or for synaptogenesis.

Animals↗
PubMed2005

End-labeled free-solution electrophoresis of DNA.

DNA is a free-draining polymer. This subtle but "unfortunate" property of highly charged polyelectrolytes makes it impossible to separate nucleic acids by free-flow electrophoresis. This is why one must typically use a sieving matrix, such as a gel or an entangled polymer solution, in order to obtain some electrophoretic size separation. An alternative approach consists of breaking the charge to friction balance of free-draining DNA molecules. This can be achieved by labeling the DNA with a large, uncharged molecule (essentially a hydrodynamic parachute, which we also call a drag-tag) prior to electrophoresis; the resulting methodology is called end-labeled free-solution electrophoresis (ELFSE). In this article, we review the development of ELFSE over the last decade. In particular, we examine the theoretical concepts used to predict the ultimate performance of ELFSE for single-stranded (ssDNA) sequencing, the experimental results showing that ELFSE can indeed overcome the free-draining issue raised above, and the technological advances that are needed to speed the development of competitive ELFSE-based sequencing and separation technologies. Finally, we also review the reverse process, called free-solution conjugate electrophoresis (FSCE), wherein uncharged polymers of different sizes can be analyzed using a short DNA molecule as an electrophoretic engine.

DNA↗
PubMed2004

Prenatal diagnosis of Shone's syndrome: parental counseling and clinical outcome.

OBJECTIVE: To describe a series of fetuses diagnosed as having Shone's syndrome, which includes four cardiac defects and for which there is a wide variety of clinical presentations, surgical treatments and outcomes, and to discuss the counseling strategy. METHODS: We reviewed retrospectively the records of four babies who were suspected prenatally to have Shone's syndrome. RESULTS: The mean age at diagnosis was 27.5 (range, 22-35) weeks. A small left ventricle, mitral and aortic annulus and ascending aorta were detected in three cases. In three fetuses there was an abnormal mitral valve apparatus and in two fetuses a sub-aortic membrane was detected. Coarctation of the aorta was an impending diagnosis in three babies. Following counseling, all parents decided to continue the pregnancy to term. Echocardiographic evaluation was performed soon after birth. The mean mitral valve annulus diameter was 8.2 (range, 7-10) mm, and that of the aortic valve annulus was 6 (range, 5-7) mm. The aortic valve was bicuspid in all babies with an additional sub-aortic membrane in two babies. Doppler ultrasound examination revealed high-velocity flow through the mitral valve in three babies; two of them had a parachute mitral valve. Coarctation repair was performed in two babies during the first week of life. One patient underwent mitral valvuloplasty followed by later mitral valve replacement. All patients were alive after a mean of 7.8 (range, 3.3-10.5) years' follow-up. CONCLUSION: When counseling families regarding fetal Shone's syndrome, it is important to emphasize the wide variety of clinical presentations and possible outcomes. Differentiation between hypoplastic left ventricle and Shone's complex is crucial and may influence the physician's attitude, the presentation of the case to the family and the family's final decision.

Counseling↗
PubMed1998

Oligomeric structure and tissue distribution of ficolins from mouse, pig and human.

Mouse plasma ficolin was purified by GlcNAc affinity and anion-exchange chromatography. Gel-filtration chromatography and gradient sedimentation indicated that mouse plasma ficolin is a 12-mer of approximately 35 kDa subunits, and electron microscopy showed the same parachute-like structure previously characterized for the pig ficolin 12-mer. Whereas the predominant form in pig plasma is a 24-mer, mouse and human plasma ficolin showed only the 12-mer form. We conclude that mouse plasma ficolin corresponds to the recently described ficolin A. We have identified a second mouse ficolin gene, ficolin B, which means that pig and mouse each have two ficolin genes, and human has three. One ficolin gene in all species is expressed in liver and is the primary source of plasma ficolin. Expression of this gene in other tissues, and expression of the second ficolin gene, appears to vary in different species.

Amidohydrolases↗
PubMed2002

Retinoids inhibit squamous cell carcinoma growth and intercellular communication.

BACKGROUND: Retinoids have been shown to inhibit the growth of squamous cell carcinoma and other malignancies. They have also been shown to alter gap junctional intercellular communication (GJIC) and the expression of connexins, the protein subunits of gap junctions. We report in this study that the alteration of GJIC by retinoids may be directly related to inhibitory effects on cell growth. MATERIALS AND METHODS: SCC-13 cells were treated with all-trans retinoic acid (tRA) and 13-cis retinoic acid (cRA) at 10(-7) and 10(-6) M concentrations in culture. No treatment and ethanol vehicle controls were included for each experiment. Serial cell counts of parallel cultures were performed to determine cell growth. The parachute technique was performed in combination with fluorescence activated cell sorting (FACS) analysis to determine GJIC. Northern and Western blot analysis were performed to assess connexin mRNA and protein expression. RESULTS: The growth rate was inhibited for cells treated with tRA (10(-6) M) (P < 0.05) and cRA (10(-6) M) (P = 0.068) vs. vehicle control. GJIC was significantly inhibited with both tRA (10(-7) and 10(-6) M) (P < 0.001) and cRA (10(-7) and 10(-6) M) (P < 0.001) at 24, 48, and 96 h as determined by FACS analysis. To correlate GJIC with cell growth, we studied the effect of glycyrrhetinic acid, a known inhibitor of GJIC. Glycyrrhetinic acid also significantly inhibited cell growth (P < 0.05) vs. control. Connexin 26 and connexin 43 mRNA and protein expression were not significantly altered after retinoid treatment. CONCLUSION: Retinoic acids inhibit both cell growth and GJIC in SCC-13 cells. Retinoids may inhibit cell growth through alteration of GJIC in SCC-13 cells.

Blotting, Northern↗
PubMed2001

Direct measurement of erythrocyte deformability in diabetes mellitus with a transparent microchannel capillary model and high-speed video camera system.

To measure erythrocyte deformability in vitro, we made transparent microchannels on a crystal substrate as a capillary model. We observed axisymmetrically deformed erythrocytes and defined a deformation index directly from individual flowing erythrocytes. By appropriate choice of channel width and erythrocyte velocity, we could observe erythrocytes deforming to a parachute-like shape similar to that occurring in capillaries. The flowing erythrocytes magnified 200-fold through microscopy were recorded with an image-intensified high-speed video camera system. The sensitivity of deformability measurement was confirmed by comparing the deformation index in healthy controls with erythrocytes whose membranes were hardened by glutaraldehyde. We confirmed that the crystal microchannel system is a valuable tool for erythrocyte deformability measurement. Microangiopathy is a characteristic complication of diabetes mellitus. A decrease in erythrocyte deformability may be part of the cause of this complication. In order to identify the difference in erythrocyte deformability between control and diabetic erythrocytes, we measured erythrocyte deformability using transparent crystal microchannels and a high-speed video camera system. The deformability of diabetic erythrocytes was indeed measurably lower than that of erythrocytes in healthy controls. This result suggests that impaired deformability in diabetic erythrocytes can cause altered viscosity and increase the shear stress on the microvessel wall.

Adult↗
PubMed1990

Single papillary muscle and ostium primum defect.

Parachute mitral valve (single papillary muscle) is commonly associated with complete atrioventricular (AV) canal. We report a case of ostium primum defect associated with single papillary muscle.

Echocardiography, Doppler↗
PubMed1986

Double mitral valve orifice.

A two-day-old baby with a type-I truncus arteriosus and double mitral valve orifice is reported. The double mitral valve orifice and additional lesions of each subdivision of the mitral valve were clearly shown by two-dimensional echocardiography. The medial orifice had a cleft leaflet and the lateral one a parachute-like disposition of the tension apparatus. This is the first report of double mitral valve orifice associated with truncus arteriosus, and the first in which anomalies of the subdivisions of the mitral valve were detected by two-dimensional echocardiography.

Echocardiography↗