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PubMed1994

Diamond flap anoplasty in infants and children with an intractable anal stricture.

After posterior sagittal anorectoplasty for imperforate anus a prolonged course of anal dilatations is necessary until the scar softens. Although rare, severe stricture after this procedure is difficult to resolve. Y-V plasty is not entirely satisfactory because the pedicle advanced into the anus has some tension, which tends to retract producing recurrent stricture. The authors performed a diamond-shaped island anoplasty in eight children with postoperative and strictures (one after an unsuccessful Y-V plasty), with prompt resolution of the stricture in five. The island flap anoplasty consists of a diamond-shaped flap of skin formed laterally, with complete separation of skin and subcutaneous attachments around the periphery of the flap. The skin island is supplied with blood from the deep tissue. An incision is made through the scarred anal ring and into the mucosa, a distance of half the length of the diamond, which is then advanced into the mucosal defect. The defect lateral to the advanced flap is sutured closed. The island of skin descends naturally into the anus, under no tension. The procedure can be performed simultaneously in the 3 o'clock and 9 o'clock positions, and can later be repeated anteriorly and posteriorly, although this has not been necessary. Two of the eight children have required no dilatation postoperatively, a distinct advantage in the 4-year-old patient. One segment in one child sloughed, resulting in repeat stricture that is responding to dilatation. The other seven children are doing well with their colostomies closed.

Anus, Imperforate↗
PubMed2005

Cardiac and CNS defects in a mouse with targeted disruption of suppressor of fused.

The hedgehog (Hh) pathway is conserved from Drosophila to humans and plays a key role in embryonic development. In addition, activation of the pathway in somatic cells contributes to cancer development in several tissues. Suppressor of fused is a negative regulator of Hh signaling. Targeted disruption of the murine suppressor of fused gene (Sufu) led to a phenotype that included neural tube defects and lethality at mid-gestation (9.0-10.5 dpc). This phenotype resembled that caused by loss of patched (Ptch1), another negative regulator of the Hh pathway. Consistent with this finding, Ptch1 and Sufu mutants displayed excess Hh signaling and resultant altered dorsoventral patterning of the neural tube. Sufu mutants also had abnormal cardiac looping, indicating a defect in the determination of left-right asymmetry. Marked expansion of nodal expression in 7.5 dpc embryos and variable degrees of node dysmorphology in 7.75 dpc embryos suggested that the pathogenesis of the cardiac developmental abnormalities was related to node development. Other mutants of the Hh pathway, such as Shh, Smo and Shh/Ihh compound mutants, also have laterality defects. In contrast to Ptch1 heterozygous mice, Sufu heterozygotes had no developmental defects and no apparent tumor predisposition. The resemblance of Sufu homozygotes to Ptch1 homozygotes is consistent with mouse Sufu being a conserved negative modulator of Hh signaling.

Animals↗
PubMed1998

Paravaginal repair of lateral vaginal wall defects by fixation to the ischial periosteum and obturator membrane.

OBJECTIVE: The aim of the study was to evaluate the anatomic basis, efficacy, and safety of a technique for correcting lateral wall vaginal defects. STUDY DESIGN: Phase I was cadaveric dissection carried out to ascertain the strength and position of structures likely to support lateral vaginal wall defects. The ischial periosteum just anterior to the ischial spine was found to be strong tissue, relatively free of nerves and vessels. In phase II, paravaginal defects were repaired by placing sutures through the arcus tendineus and underlying obturator fascia, obturator membrane, and ischial periosteum. Other defects and urinary incontinence were corrected within the same surgical setting. Forty patients were followed up for an average of 39 months (range 7-52 months). Preoperative evaluation consisted of an extensive history, cough stress test, spontaneous uroflowmetry, postvoid residual urine determination, urethral axis determination, site-specific pelvic floor defect evaluation, and multichannel urodynamic studies. After the operation patients underwent evaluations at 3 months, at 6 months, and then annually. RESULTS: Objective site-specific re-examination of the 40 patients revealed the following recurrences: lateral wall in 1 of 40 procedures, anterior wall in 3 of 35 procedures, posterior wall in 1 of 36 procedures, and apical wall in 1 of 27 procedures. Thirty-four of 36 women (94.4%) with urodynamically confirmed genuine stress incontinence or potential incontinence achieved cure (P <.001). CONCLUSIONS: (1) The ischial periosteum and obturator membrane are consistently strong reattachment sites. (2) Repair of paravaginal defects with these tissues is effective and safe. (3) Urodynamic parameters were unchanged after the operation except for measures of incontinence, which were improved (P <.001). (4) Performing other pelvic procedures did not negatively alter the success rates of paravaginal repair. (5) The urethral axis was favorably altered after the operation (P <.01).

Abdomen↗
PubMed2000

Heterotaxy with left atrial isomerism in a patient with deletion 18p.

We report on a female infant with partial deletion of the short arm of chromosome 18 (del 18p) and heterotaxy with left atrial isomerism. Congenital heart defect (CHD) is found in 10% of the literature reports. Interestingly, situs abnormalities have been diagnosed in four patients with del 18p, including ours. This finding could imply that a locus or loci involved in the development of normal body situs lies within this chromosomal region. Del 18p must be consid- ered when evaluating a patient with phenotypic anomalies and CHD in lateralization defects.

Chromosome Deletion↗
PubMed1990

Abnormal meiotic spindles cause a cascade of defects during spermatogenesis in asp males of Drosophila.

Since spermatogenesis in Drosophila is a series of interconnected and interdependent steps and most of the spermatogenic events take place in the absence of transcription, failures in a given stage can give rise to a cascade of defects later on. The asp locus of Drosophila melanogaster codes for a non-tubulin component implicated in proper spindle structure and/or function (Ripoll et al. 1985). Homozygous asp males exhibit abnormal meiotic spindles giving rise to altered segregation of chromosomes and mitochondria and failures in cytokinesis. Postmeiotic spermatogenic stages of asp males show a series of alterations that we interpret as due to the previously occurring defective meiosis because meiotic spindles are the only microtubular structure altered in mutant testes. The most conspicuous alterations are: (i) variable size of nuclei and nebenkerns of early spermatids, which are also multinucleate instead of having single and uniformly sized nuclei; (ii) elongating spermatids in which abnormal-sized mitochondrial derivatives elongate alongside more than one axoneme; (iii) failures in the individualization process, where abnormal spermatids remain syncytial, and seem to be eliminated during the coiling stage.

Animals↗
PubMed2006

Embryonic fibroblasts from mice lacking Tgif were defective in cell cycling.

Holoprosencephaly (HPE) is the most common structural anomaly of the human brain, resulting from incomplete cleavage of the developing forebrain during embryogenesis. Haploinsufficient mutations in the TG-interacting factor (TGIF) gene were previously identified in a subset of HPE families and sporadic patients, and this gene is located within a region of chromosome 18 that is associated with nonrandom chromosomal aberrations in HPE patients. TGIF is a three-amino-acid loop extension (TALE) homeodomain-containing transcription factor that functions both as a corepressor of the transforming growth factor beta (TGF-beta) pathway and as a competitor of the retinoic acid pathway. Here we describe mice deficient in Tgif that exhibited laterality defects and growth retardation and developed kinked tails. Cellular analysis of mutant mouse embryonic fibroblasts (MEFs) demonstrated for the first time that Tgif regulates proliferation and progression through the G1 cell cycle phase. Additionally, wild-type human TGIF was able to rescue this proliferative defect in MEFs. In contrast, a subset of human Tgif mutations detected in HPE patients was unable to rescue the proliferative defect. However, an absence of Tgif did not alter the normal inhibition of proliferation caused by treatment with TGF-beta or retinoic acid. Developmental control of proliferation by Tgif may play a role in the pathogenesis of HPE.

Animals↗
PubMed1999

Quantification of Viable Myocardium in Multivessel Coronary Disease: Effects of the Redistribution Time after Reinjection Of Thallium-201 and Comparison with Postrevascularization Defect Size.

Reinjection of 201Tl is used for improved detection of viable myocardium. Prospectively the effect of the redistribution time after injection for the quantification of the definitive perfusion defect size in multivessel coronary heart disease and severely impaired left ventricular function was examined. Thirty patients were included preoperatively before CABG. The study was performed with 80-90 MBq 201Tl-Cl and reinjection (40-50 MBq). Imaging was performed after an exercise test and 3 hours afterwards. Thereafter, the reinjection dose was given and repeated studies were performed 10 minutes, 2 hours, and 20 hours later. Defect sizes were compared with the 3-hour rest-study without reinjection. Imaging studies were repeated postoperatively. The defect size was expressed as % of left ventricular total myocardium. Perfusion defect sizes were as follows: post-stress study (27%), 3 hour rest-study (17%), post-reinjection-10 min (12%), 2 hours (9%), and 20 hours (7%). Compared with the 3 hour rest-study, the perfusion defect was reduced only in 7/30 patients in the study immediately after reinjection. In the delayed studies, defect sizes were markedly smaller (p < 0.05) both in studies 2 hours and 20 hours after reinjection. In 15/30 patients there was a marked reduction of 50% of defect sizes in the study 2 hours post-reinjection vs the 3 hour rest-study. The residual defects at 2 hours after reinjection were identical to the postoperative defect sizes (10%). Further prolongation of the redistribution time to 20 horus caused an additional small reduction in defect size only in two patients compared with the 2-hour post-reinjection images (n.s.). Using a marker as 201Tl with redistribution characteristics, the redistribution time after reinjection is of utmost importance to correctly identify the definitive size of the perfusion defect vs viable myocardium in patients with multivessel disease. A delay of 2 hours for redistribution after the reinjection most correctly corresponds to the postop defect size; a longer redistribution time did not provide additional advantages.

Journal Article↗
PubMed1999

Conserved requirement for EGF-CFC genes in vertebrate left-right axis formation.

Specification of the left-right (L-R) axis in the vertebrate embryo requires transfer of positional information from the node to the periphery, resulting in asymmetric gene expression in the lateral plate mesoderm. We show that this activation of L-R lateral asymmetry requires the evolutionarily conserved activity of members of the EGF-CFC family of extracellular factors. Targeted disruption of murine Cryptic results in L-R laterality defects including randomization of abdominal situs, hyposplenia, and pulmonary right isomerism, as well as randomized embryo turning and cardiac looping. Similarly, zebrafish one-eyed pinhead (oep) mutants that have been rescued partially by mRNA injection display heterotaxia, including randomization of heart looping and pancreas location. In both Cryptic and oep mutant embryos, L-R asymmetric expression of Nodal/cyclops, Lefty2/antivin, and Pitx2 does not occur in the lateral plate mesoderm, while in Cryptic mutants Lefty1 expression is absent from the prospective floor plate. Notably, L-R asymmetric expression of Nodal at the lateral edges of the node is still observed in Cryptic mutants, indicating that L-R specification has occurred in the node but not the lateral plate. Combined with the previous finding that oep is required for nodal signaling in zebrafish, we propose that a signaling pathway mediated by Nodal and EGF-CFC activities is essential for transfer of L-R positional information from the node.

Animals↗
PubMed2002

[Transposition of great arteries. Understanding its pathogenesis].

Transposition of the great arteries (TGA) is a frequent and severe cardiac defect. In patients with this malformation, diagnostic and surgical results and the long-term prognosis significantly improved in the last years. From the embryological point of view there are two main theories: 1) the anomalous infundibular rotation, and 2) the anomaly of the aortico-pulmonary septum. Both of them still present important limits. Moreover, TGA is difficult to reproduce by animal experiments, but interesting data, using retinoid acid in pregnant rats, are nowadays available, as well as there are interesting data from the epidemiologic studies on human teratologic agents. TGA is rarely associated with genetic syndromes and with additional extracardiac anomalies. A few cases are in relation with DiGeorge syndrome with deletion of chromosome 22q11. On the contrary TGA is significantly prevalent, in association with other cardiac and extracardiac anomalies, in children with lateralization defects, heterotaxy and asplenia syndrome (right isomerism). However in patients with heterotaxy and polysplenia syndrome (left isomerism) TGA is significantly more rare. In mice with mutation of Smad2 and NODAL, two genes involved in the lateralization process, some cases of TGA, with or without right isomerism of the lungs, were reported. Moreover, in families with heterotaxy some cases with congenitally corrected TGA were reported and a new gene associated with heterotaxy, CRYPTIC, can present mutations in patients with "isolated" TGA. A recent study on familiar recurrence of TGA shows in the same family some cases of TGA and of corrected TGA so that a monogenic inheritance (autosomic dominant or recessive) with variable phenotypic expression can be suggested. The normal righthand spiralization of the heart is genetically determined in cases of situs solitus and d-loop of the ventricles. This pattern is not present in cases of TGA presenting a parallel position of the great arteries. On the basis of these observations and according to new epidemiologic and genetic data some cases of TGA should be classified in the group of the anomalies of lateralization and ventricular loop. The mystery is still present but perhaps some gleams of light are appearing.

Animals↗
PubMed2003

Factors affecting capacitive current diversion with a uterine resectoscope: an in vitro study.

STUDY OBJECTIVE: To evaluate electrosurgical waveform, generator type, and electrode integrity as variables in capacitive induction of current on the external sheath of a resectoscope in open-circuit conditions. DESIGN: In vitro, laboratory, comparative study (Canadian Task Force classification CII-1). SETTING: Surgical laboratory. INSTRUMENTATION: Three ValleyLab radiofrequency (RF) electrosurgical generators (ESU), Force-2, Force-4, and Force-F/X; a resectoscope (Storz 50 series); and rollerball electrodes, both intact and with two types of standard insulation defects (lateral and circumferential) placed in two locations: distally, beyond the end of the telescope, and proximally, beside the distal aspect of the telescope. A Dynatek ESU analyzer was used to record current and wattage on electrodes and the external sheath. MEASUREMENTS AND MAIN RESULTS: With intact insulation, current was not disproportionately induced on the external sheath of the resectoscope regardless of ESU, power, or waveform. Proximally located electrode insulation defects allowed induction of most of the generator's output to the external sheath when high-voltage modulated outputs were used, and the risk varied somewhat with the ESU. There was no such induction at any power setting or with any insulation defect when low-voltage (cutting) outputs were tested. CONCLUSION: In the presence of proximal electrode defects, high-voltage currents may contribute to thermal injury to the lower genital tract during RF resectoscopic surgery.

Electric Capacitance↗
PubMed2007

Left-right asymmetry in vertebrate development.

Externally the vertebrate body plan presents a bilateral symmetry in relation to the midline. However, inside the body the distribution of the visceral organs follows a very particular pattern that is not symmetrical in relation to the midline. The last 10 years have seen remarkable advances in our understanding of how the internal asymmetries typical of the vertebrate body are established and controlled. The use of different development models has permitted to uncover fascinating ways of creating asymmetry, like the activity of the nodal cilia. A host of studies has also unravelled the involvement of many genes in the left right patterning pathway. Based on this knowledge the genetic basis of human laterality defects are beginning to be revealed. It is a major challenge now to understand how all these genes control left right development as well as the complex set of interactions established between them.

Animals↗
PubMed1996

Ongoing vascular laboratory surveillance is essential to maximize long-term in situ saphenous vein bypass patency.

PURPOSE: The purpose of this study was to assess the contribution of ongoing graft surveillance to maximize long-term patency of lower limb in situ saphenous vein bypasses. METHODS: From January 1981 to October 1994, 556 autogenous grafts were constructed in 499 patients. The distal anastomosis was at the popliteal level in 207 (37%) and the tibial level in 349 (63%). All patients were enrolled in a prospective surveillance protocol to identify lesions that compromise graft patency and were evaluated at 1 day, 1 week, 6 weeks, and 3 months. Surveillance studies were then obtained every 3 months for the first 2 postoperative years and every 6 months thereafter. RESULTS: Four-hundred-fifty abnormalities were detected in 236 grafts. The median interval from the initial procedure to detection of an abnormality was 12 months (range 0 to 113 months) and varied with the location of the defect. Later in the life of the graft, progression of atherosclerotic disease manifested as inflow obstruction at a median of 15 months, and outflow disease threatened the graft at a median of 29 months (r = 0.0003). Of the 450 surveillance abnormalities, 294 (65%) occurred within the first 2 years after operation, and 156 (35%) developed more than 2 years after operation. Of the 236 grafts that developed surveillance abnormalities, 50 (21%) developed the initial defect more than 2 years after the initial bypass procedure. Eleven percent of grafts remaining free of abnormality after 2 years went on to fail. Sixty-seven interventions were performed on 62 extremities after 24 months, with 30 involving previously unrevised grafts. CONCLUSIONS: Because lesions amenable to revision continue to develop years after vein bypass construction, perpetual surveillance is required to ensure optimal rates of graft patency.

Analysis of Variance↗
PubMed1993

Lateralized attentional abnormality in schizophrenia is correlated with severity of symptoms.

Numerous studies have demonstrated a lateralized impairment of attention in schizophrenia. In this study, attention in schizophrenia is investigated with a task that involves centering a rod while blindfolded. Symptoms were rated on the Brief Psychiatric Rating Scale (BPRS) for each of the 20 schizophrenic subjects. The more symptomatic patients demonstrated a right-sided hemineglect compared to the less symptomatic patients (p = 0.013). Furthermore, the difference between more and less symptomatic patients was even more distinct when they were categorized by the BPRS schizophrenia subscale alone (p = 0.0025). These findings support the hypothesis that the pathophysiology of schizophrenia involves a lateralized defect in the control of attention, and that this defect is associated with the severity of symptoms. This raises the possibility that effects of neuroleptic medication may be asymmetric, which could account for some of the inconsistencies in studies of hemispheric dysfunction in schizophrenia.

Adult↗
PubMed2005

Deficiency of SPAG16L causes male infertility associated with impaired sperm motility.

The axonemes of cilia and flagella contain a "9+2" structure of microtubules and associated proteins. Proteins associated with the central doublet pair have been identified in Chlamydomonas that result in motility defects when mutated. The murine orthologue of the Chlamydomonas PF20 gene, sperm-associated antigen 16 (Spag16), encodes two proteins of M(r) approximately 71 x 10(3) (SPAG16L) and M(r) approximately 35 x 10(3) (SPAG16S). In sperm, SPAG16L is found in the central apparatus of the axoneme. To determine the function of SPAG16L, gene targeting was used to generate mice lacking this protein but still expressing SPAG16S. Mutant animals were viable and showed no evidence of hydrocephalus, lateralization defects, sinusitis, bronchial infection, or cystic kidneys-symptoms typically associated with ciliary defects. However, males were infertile with a lower than normal sperm count. The sperm had marked motility defects, even though ultrastructural abnormalities of the axoneme were not evident. In addition, the testes of some nullizygous animals showed a spermatogenetic defect, which consisted of degenerated germ cells in the seminiferous tubules. We conclude that SPAG16L is essential for sperm flagellar function. The sperm defect is consistent with the motility phenotype of the Pf20 mutants of Chlamydomonas, but morphologically different in that the mutant algal axoneme lacks the central apparatus.

Animals↗
PubMed2002

Ivemark syndrome with agenesis of the corpus callosum: a case report with a review of the literature.

Asplenia associated with situs ambiguus, symmetric liver, bilateral trilobulated lungs, and a complex heart defect was diagnosed on autopsy in a 14-day-old infant. Furthermore, examination of the brain displayed agenesis of the corpus callosum (ACC) with pachygyria and hydrocephalus. The characteristic association of asplenia with visceroatrial heterotaxia is traditionally named after the Swedish pediatrician, Ivemark. Although exceptional, association of Ivemark syndrome with callosal agenesis has been reported recently. The concept of 'developmental fields' describes morphogenetically reactive units of the embryo determining and controlling the development of complex structures in a hierarchical manner. Lateralization defects such as situs inversus, asplenia or polysplenia due to defective left-right axis development, as well as decussation defects such as ACC, are considered as defects of the primary developmental field. Therefore, additional callosal agenesis in Ivemark syndrome may be a coherent and synchronic defect in the primary developmental field rather than a causally independent malformation.

Abnormalities, Multiple↗
PubMed1982

An injection impression technique for palatal defects.

A master cast suitable for fabricating a retentive flexible base using any of the materials and techniques previously mentioned is provided. The flexible extension fits snugly into the defect laterally and extends above the remnants of the soft palate posteriorly and into the nasal floor anteriorly on either side of the remnants of the nasal septum (Fig. 9). The use of a thin flexible extension such as Molloplast will provide a good chemical bond to the acrylic resin of the denture base, allows for easy cleaning, and will maintain flexibility for several years. Prostheses constructed with this technique are retained well. The technique described will provide increased mechanical retention of prostheses for defects of the palate by engaging undercuts around the borders of the defect with a flexible material. The impression is made by injecting an elastic impression material with a syringe through a hole prepared in the palate of the impression tray. This technique may not always be required, but is recommended where a retention problem is anticipated and there is difficulty in obtaining a satisfactory flow of the impression material to the appropriate undercut. A correct impression can be secured the first time, overcoming further discomfort and inconvenience to the patient.

Dental Impression Technique↗
PubMed2005

Paravaginal defects: a comparison of clinical examination and 2D/3D ultrasound imaging.

BACKGROUND: Paravaginal defects are often assumed to be the underlying anatomical abnormality in anterior compartment descent. Neither clinical examination nor ultrasound assessment are generally accepted diagnostic modalities. AIMS: To compare clinical examination and translabial 3D ultrasound in the detection of such defects. METHODS: Fifty-nine women without previous prolapse or incontinence surgery were seen prospectively. Clinical and ultrasound assessments were carried out in blinded fashion. 3D translabial ultrasound was undertaken after voiding and supine. Volumes were acquired at rest, on Valsalva and on levator contraction. Loss of paravaginal support ('tenting') in the axial plane was taken to signify paravaginal defects. RESULTS: Paravaginal defects were reported clinically in 14 cases on the left (24%), 19 times on the right (32%). Two 3D ultrasound examinations did not yield satisfactory volumes, leaving 57 for analysis. Neither midsagittal nor coronal views yielded data that correlated with clinical assessments. In the axial plane there was absence of tenting at rest in 32/57 (57%) patients, but this did not correlate with clinical findings. Loss of tenting on Valsalva was observed less often (21/57, 37%) and was weakly associated with clinically observed lateral defects (P = 0.036). CONCLUSIONS: Pelvic floor ultrasound in midsagittal, axial or coronal planes does not correlate well with clinical assessment for paravaginal defects. This could be due to poor clinical assessment technique or limitations of the ultrasound method. On the other hand, paravaginal defects may be uncommon or clinically irrelevant. On present knowledge, the paravaginal defect has to be regarded as an unproven concept.

Adult↗
PubMed2001

Long term neurodevelopmental and behavioral effects of perinatal life events in rats.

Modern neurosciences are now able to open new avenues concerning an experimental approach to clinical neurosciences and psychiatry. Detection and prediction of potential vulnerabilities such as behavioral disturbances and neurodegenerative diseases, are urgent tasks leading to prevention that must be encouraged in parallel to the enormous efforts displayed for treatments. Besides possible genetic origins of diseases, environmental factors are now coming under scrutiny, and especially deleterious and challenging life events and stress occurring during prenatal and postnatal critical periods may orient brain functions towards deleterious developments. The hypothesis that will be examined is that early events might be at the origin of pathological transformations and symptoms after long periods of apparent normal abilities and behavioral homeostasis. We used models of prenatal stress and postnatal manipulations such as cross-fostering. It will be demonstrated that such events induce long-term changes, cognitive and emotional modifications appearing first, when offspring are adults, followed by cognitive defects later in life. Increased sensitivity of the hypothalamic pituitary-adrenal axis (HPA), the endocrine system controlling the secretion of stress hormones (corticoids), appears to be a major element of pathogenesis. HPA axis dysfunction appears very early after birth (3 days) and lasts for months. Cumulative exposure to high levels of hormones seems to be detrimental for some brain regions, especially the hippocampus and major neurotransmitter systems such as dopamine neurons. We evidenced that neuronal modifications in hippocampal region are correlated with behavioral and cognitive defects, relating environment, stress in early life, hormonal changes, long-term neuropathological processes and impaired cognition in aging. Moreover appears in offspring, when adults, a proneness to engage in drug dependence. These data emphasize the need to consider early environmental life events as etiological factors for delayed neuropsychiatric disturbances, neurodegenerative defects included. Moreover, they strengthen the interest for a longitudinal approach to promote experimental psychopathology.

Journal Article↗