Communication issues in 22q11.2 deletion syndrome: children at risk.

PURPOSE: The purpose of this investigation is to describe the communication profile of children with the 22q11.2 deletion syndrome from infancy through school age and to examine the influence of other medical aspects, such as palate anomalies, learning disorders, and cardiac defects of the syndrome to communication. METHODS: Seventy-nine children were examined using standardized tests of speech and language and perceptual measures of resonance and voice. RESULTS: Results show significant delay in emergence of speech and language milestones with delay/disorder in speech-language processes persisting into the school aged years, including those children diagnosed with nonverbal learning disabilities. Persistent articulation and resonance disorders were also present, presumed to be related in part to palatal anomalies. No correlation was found between cardiac status, learning disorders, palate anomalies and communication disorders. CONCLUSION: The need for early identification and management of communication skills is crucial in the care of children with the 22q11.2 deletion.

Synthetic hybrid grafts for craniofacial reconstruction: sustained gene delivery using a calcium phosphate bone mineral substitute.

These experiments were performed to evaluate the efficacy of a biocompatible bone cement, Norian CRS, engineered as a hybrid graft for simultaneous bone matrix reconstruction and sustained, site-directed gene transfer using an adenoviral vector. Norian CRS was cured ex vivo by mixing a calcium source powder with a phosphate source solution to form a paste. To 1.0 ml of the cement was added 50 microl of a solution containing 1 x 10(8) plaque-forming units of a replication-deficient adenoviral vector containing a bacterial beta-galactosidase reporter gene (AdLacZ). In vitro, fragments of the hybrid Norian-AdLacZ construct were placed into 12-microm-pore culture plate inserts and cocultured with human fibroblasts. The same insert was transferred to a new well of fibroblasts every 48 hours for 30 days, and, after allowing 72 hours for gene expression, fibroblasts were examined for transgene expression by 5 bromo-4-chloro-3-indoyl-beta-D-galactosidase (X-gal) staining. In vivo, the Norian-AdLacZ hybrid was implanted into 10-mm frontal bone defects in 3-week-old piglets. The implant sites were harvested after 5 days and were examined for transgene expression by X-gal staining. X-gal staining of fibroblasts incubated with the hybrid Norian-AdLacZ construct was observed throughout the 30-day period. Transgene expression was also observed about the periphery of the calvarial defects treated with hybrid Norian-AdLacZ constructs. Thus, adenoviral vectors may be incorporated successfully into a synthetic calcium phosphate bone mineral substitute to provide effective, sustained local gene delivery.

Toward an understanding of nonsyndromic craniosynostosis: altered patterns of TGF-beta receptor and FGF receptor expression induced by intrauterine head constraint.

Although the etiology of nonsyndromic forms of craniosynostosis remains uncertain, recent experiments from our laboratory have demonstrated that fetal head constraint induces cranial suture fusion in mice through a process associated with altered patterns of transforming growth factor beta (TGF-beta) isoform expression. Other recent studies have highlighted the role of secreted signaling molecules, including members of the TGF-beta superfamily and the fibroblast growth factors (FGFs), as well as their receptors, in regulating suture development and fusion. The purpose of these experiments was to examine the potential role of TGF-beta receptors and FGF receptor 2 (FGFR2) in nonsyndromic craniosynostosis by determining their temporospatial patterns of expression during development complicated by intrauterine head constraint. This study consisted of two groups of C57BI/6J mice: an experimental group subjected to intrauterine constraint and a control unconstrained group. Fetal head constraint was induced by performing uterine cerclage on day 17.5 of gestation and allowing intrauterine fetal growth to continue 24 and 48 hours beyond the normal gestational period. Control animals underwent hysterotomy on day 17.5 and the nonconstrained pups were allowed to continue intra-abdominal fetal growth 48 hours beyond normal gestation. Expression of TGF-beta receptor types I and II, and FGFR2 in the calvarial tissue was determined by immunohistochemical analysis. In the unconstrained control animals, there was minimal immunoreactivity for both TGF-beta receptors and FGFR2 within the coronal suture. After 24 hours of constraint, however, there was a marked increase in immunoreactivity of TGF-beta receptors and FGFR2 in the osteoblasts along the osteogenic fronts and in the dural cells. After 48 hours, there was continued expression of both type I and type II receptors and FGFR2 within the midsutural mesenchyme of the coronal suture, in the osteoblasts, and in the dura. The authors demonstrated substantial upregulation of TGF-beta receptor types I and II and FGFR2 in coronal sutures subjected to in utero constraint. These results suggest an important role for TGF-beta/TGF-beta receptor, and FGF/FGFR signaling in the pathogenesis of constraint-induced craniosynostosis.

Cleft palate repair at 3 to 7 months of age.

We report the speech outcome in 90 children with complete unilateral cleft lip and palate who underwent soft palate repair either between 3 and 7 months of age (n = 40) or later than 7 months of age (n = 50). In all patients, palatoplasty was performed by one of two experienced surgeons using a modification of the Furlow technique, and speech evaluations were conducted using the Pittsburgh Weighted Values for Speech Symptoms Associated with Velopharyngeal Incompetence by two speech pathologists with high inter-rater reliability. There were no differences between the groups with respect to resonance, nasal air emission, and articulation. Velopharyngeal function, as measured by the total speech score, was similar between the two groups of patients, as were the rates of secondary pharyngoplasty. These results suggest that very early closure of the soft palate may not offer significant benefit over repair later in infancy with respect to speech outcome.

Cleft lip and palate.

The most common congenital deformity of the head and neck, cleft lip and palate, presents the surgeon with a unique esthetic and reconstructive challenge. The complexity of these deformities demands the skills of a multidisciplinary team of professionals to optimize surgical outcome. This article discusses the embryology, epidemiology, and genetics of cleft lip and palate and details the history and modern methods of their surgical correction, the proper goal of which is restoration of normal facial form and velopharyngeal function.

Treatment of pyogenic granuloma by shave excision and laser photocoagulation.

We present herein our technique for the management of pyogenic granulomas. Twenty such lesions were treated in 13 patients by shave excision followed by laser photocoagulation of the base. Recurrence was noted in just one case and was successfully treated by repeated laser treatment. The cosmetic results have been uniformly excellent. Shave excision followed by laser photocoagulation is an effective therapeutic alternative to excision and linear closure for the treatment of pyogenic granuloma, one that minimizes scar formation while preserving the ability to confirm the diagnosis.

Salvage of free flaps after secondary venous ischemia by local delivery of heparin.

Recent studies have demonstrated that heparin may protect against reperfusion injury through a direct effect on the microvascular endothelium that is independent of its effect on systemic coagulation. The purpose of this study was to determine whether local delivery of low-dose heparin has a role in the salvage of musculocutaneous flaps after secondary venous ischemia and revascularization. Cutaneous maximus musculocutaneous flaps were transplanted to the contralateral groin in adult Sprague-Dawley rats. All flaps were subjected to 2 hours of primary arteriovenous ischemia followed by 20 hours of reperfusion. The flaps were then subjected to a 6-hour secondary venous ischemic insult followed by anastomotic revision and reperfusion. Animals in group I received no adjunctive treatment. Those in group II were treated with low-dose heparin (5-6 U per kilogram per hour) infused systemically via the inferior epigastric vein. Those in group III received the same dose of heparin infused locally into the flap via the inferior epigastric artery. The dose of heparin used in groups II and III was insufficient to prolong the activated partial thromboplastin time above normal values. At 7 days, mean flap necrosis was 60.8% in group I and 62.1 in group II. Local heparin delivery (group III) resulted in complete survival of all flaps. Histological examination after 48 hours of reperfusion demonstrated improved microvascular patency and reduced neutrophilic infiltration in the flaps of group III animals. Thus, local infusion of low-dose heparin resulted in significantly improved flap salvage through a mechanism independent of its effect on systemic coagulation.

Cleft-palate repair by modified Furlow double-opposing Z-plasty: the Children's Hospital of Philadelphia experience.

Although the optimal technique of cleft-palate repair remains controversial, several small series have suggested that superior speech results may be obtained with the Furlow double-opposing Z-plasty. To examine speech outcome in a large series of Furlow palatoplasties performed at a single center, we retrospectively reviewed the records of 390 cleft-palate patients who underwent Furlow palatoplasty at The Children's Hospital of Philadelphia from 1979 to 1992. Speech outcome at 5 years of age or greater was available for 181 nonsyndromic patients and was scored using the Pittsburgh Weighted Values for Speech Symptoms Associated with Velopharyngeal Incompetence. No or mild hypernasality was noted in 93.4 percent of patients, with 88.4 percent demonstrating no or inaudible nasal escape and 97.2 percent demonstrating no errors in articulation associated with velopharyngeal incompetence. Secondary pharyngeal flap surgery was required in just 7.2 percent of patients. Age at palatoplasty, cleft type, and experience of the operating surgeon had no significant effect on speech results, although there was a trend toward better outcome in those undergoing palatal repair before 6 months of age and toward poorer outcome in those with Veau class I and II clefts. Overall, Furlow palatoplasty yielded outstanding speech results, with rates of velopharyngeal dysfunction that seem to improve upon those reported for other techniques.

The protective effect of L-arginine on ischemia-reperfusion injury in rat skin flaps.

The objective of this study was to examine whether the administration of L-arginine, a precursor of nitric oxide and substrate of nitric oxide synthase, prior to reperfusion could lead to decrease in neutrophil-mediated tissue injury and improved flap survival. Epigastric island skin flaps were elevated in 70 rats and rendered ischemic. Thirty minutes prior to reperfusion, the rats were treated with intraperitoneal saline (n = 15), L-arginine (n = 15), D-arginine (n = 15), or N omega-nitro-L-arginine methylester plus L-arginine in equimolar amounts (n = 15). Flap survival at 7 days and neutrophil counts at 24 hours were evaluated. Flap necrosis as expected in the sham group of animals (n = 10) was 0.0 percent, while the control (saline-treated) animals had 59.6 percent necrosis. Animals treated with L-arginine demonstrated a significant decrease in flap necrosis to 12.7 percent. This protective effect was almost completely negated by N omega-nitrol-L-arginine methylester, which significantly increased flap necrosis to 49.3 percent and was much less pronounced with D-arginine (28.6 percent). Neutrophil counts were significantly decreased in flaps from L-arginine-treated and sham animals versus both saline and N omega-nitro-L-arginine methylester-treated groups. We conclude that administration of L-arginine prior to reperfusion can significantly reduce the extent of flap necrosis and flap neutrophil counts due to ischemia-reperfusion injury. This protective effect is completely negated by nitric oxide synthase inhibition. Since L-arginine reduces the number of neutrophils within the flap and the extent of flap necrosis only in the presence of active nitric oxide synthase, we hypothesize that this protective effect of L-arginine on ischemia-reperfusion injury is secondary to a nitric oxide-mediated suppression of neutrophil-mediated injury.

Ischemia-reperfusion injury in myocutaneous flaps: role of leukocytes and leukotrienes.

Leukotriene B4 is a potent inflammatory mediator that is derived from the 5-lipoxygenase pathway of arachidonic acid metabolism and that has been implicated in the pathophysiology of polymorphonuclear leukocyte-dependent reperfusion injury in a variety of organ systems. The objectives of these investigations were to determine whether inhibition of leukotriene B4 attenuates postischemic polymorphonuclear leukocyte infiltration and subsequent injury in myocutaneous flaps. Anesthetized female Yorkshire pigs were randomized to receive normal saline (n = 8), the 5-lipoxygenase inhibitor diethylcarbamazine (n = 7), or the leukotriene B4 receptor antagonist SC-41930 (n = 7). All animals underwent 6 hours of rectus abdominis myocutaneous flap ischemia followed by 4 hours of reperfusion. In saline-treated controls, flap ischemia was associated with massive polymorphonuclear leukocyte infiltration at 1 and 4 hours of reperfusion (252 +/- 70 and 619 +/- 137 polymorphonuclear leukocytes per 25 high-power fields, respectively). Skeletal muscle neutrophil content was significantly attenuated by pretreatment with diethylcarbamazine (72 +/- 29 and 229 +/- 63 polymorphonuclear leukocytes per 25 high-power fields; p < 0.05) or SC-41930 (25 +/- 3 and 193 +/- 25 polymorphonuclear leukocytes per 25 high-power fields; p < 0.05). Wet-to-dry weight ratios of full-thickness flap biopsies were lower in the diethylcarbamazine and SC-41930 groups (2.98 +/- 0.15 and 2.90 +/- 0.26, respectively) than in the control group (4.13 +/- 0.23; p < 0.01), and mean muscle infarct size, as determined by nitroblue tetrazolium staining, diminished from 47.6 +/- 11.3 percent in controls to 25.1 +/- 6.5 percent in diethylcarbamazine-treated animals and 7.3 +/- 4.8 percent in SC41930-treated animals (p < 0.05). These data indicate that leukotriene B4 plays a critical role in mediating neutrophil-dependent injury in postischemic skeletal muscle flaps.

Reperfusion injury of postischemic skeletal muscle is attenuated by the 21-aminosteroids U-74389F and U-74500A independent of iron binding.

BACKGROUND: Lazaroids (21-aminosteroids) are a novel class of compounds that have been shown to limit experimental ischemic injury of varied causes. The mechanism of action is uncertain but may include scavenging of lipid peroxy radicals, iron binding, or direct membrane interaction. The purpose of these experiments was to evaluate the capacity of the lazaroids U-74500A and U-74389F to modify ischemia/reperfusion injury of skeletal muscle in a well-characterized model of high-grade partial ischemia. METHODS: Nonfasted male Sprague-Dawley rats were anesthetized, a tracheostomy tube was placed, and the carotid artery and jugular vein were cannulated. Animals received heparin (1 unit/gm) and crystalloid (1 ml/hr) intravenously. The baseline group (n = 6) was allowed a 30-minute equilibration period, after which resting transmembrane potential (Em) was measured in a hindlimb muscle. Muscle biopsy specimen was obtained; conjugated diene and thiobarbituric acid reactive substances were measured as indexes of lipid peroxidation. Spectrophotometric determination of plasma iron and unsaturated iron-binding capacity were performed (total iron-binding capacity and percent saturation were calculated). Animals received U-74389F (2 mg/kg, n = 7), U-74500A (2 mg/kg, n = 6), or vehicle only (0.02 mol/L citrate acid/citrate; n = 7) intraarterially before infrarenal aortic clamping was performed for 120 minutes. An additional group of animals received U-74389F (2 mg/kg, n = 7), U-74500A (2 mg/kg, n = 7), or vehicle (n = 11) intraarterially before infrarenal aortic clamping was performed for 120 minutes, followed by reperfusion for 30 minutes. RESULTS: Depolarization of resting Em was noted during ischemia, with partial repolarization on reperfusion, which was enhanced by either lazaroid. As expected, iron delocalization occurred during ischemia and persisted on reperfusion, with U-74500A effectively binding iron, whereas U-74389 did not. Vehicle but not the 21-aminosteroids inhibited lipid peroxidation. CONCLUSIONS: High-grade partial ischemia of skeletal muscle is associated with iron delocalization, which persists on reperfusion. Each lazaroid achieved a similar "membranoprotective" effect during reperfusion only despite lack of iron binding by U-74389F, suggesting a direct interaction with the cell membrane. These data support the concept that ischemic injury and reperfusion injury occur through fundamentally different mechanisms.

Ultraviolet excitation fluorescence spectroscopy: a noninvasive method for the measurement of redox changes in ischemic myocutaneous flaps.

In this report, we discuss application of the noninvasive technology of ultraviolet fluorescence spectroscopy to the metabolic analysis of normal and compromised myocutaneous flaps. Acute changes in tissue redox states during ischemia and reperfusion were determined analysis of changes in the fluorescence spectrum of reduced nicotinomide adenine dinucleotide (NADH). Analysis of the system for NADH fluorescence showed good correlation between excitation spectra recorded at 450 nm from pure beta-NADH and those recorded from porcine rectus abdominis myocutaneous flaps. Sequential measurements of surface fluorescence were obtained from six flaps subjected to 6 hours of warm arterial ischemia and 4 hours of reperfusion. Results were compared with spectra obtained from six contralateral nonischemic control flaps. A significant mean increase in NADH fluorescence (49 percent; p < 0.05) was demonstrated within 30 minutes of vascular occlusion. Fluorescence intensity continued to increase throughout the ischemic period, reaching 320.5 percent of baseline values at 6 hours. Reperfusion resulted in the prompt return of fluorescence intensity to baseline levels. These results show that fluorescence spectroscopy of endogenous NADH is a sensitive and reliable indicator of vascular occlusion in experimental myocutaneous flaps.

Neutrophil lipoxygenase activation and leukosequestration in postischemic myocutaneous flaps: role of LTB4.

Reperfusion of ischemic tissues leads to eicosanoid- and polymorphonuclear leukocyte (PMN)-dependent injury. The present experiments were undertaken to examine the effect of myocutaneous flap ischemia-reperfusion on neutrophil 5-lipoxygenase activity and to define the role of leukotriene B4 (LTB4) in postischemic PMN infiltration into such composite tissue grafts. Anesthetized Yorkshire pigs underwent 6 h of rectus abdominis myocutaneous flap ischemia or sham ischemia, and LTB4 generation was measured in calcium ionophore-stimulated neutrophils isolated from the circulation. At 30 min of reperfusion, neutrophil generation of LTB4 increased from a baseline value of 31.0 +/- 6.8 to 98.5 +/- 5.1 ng/5 x 10(6) PMN (P < 0.01) and was significantly greater than those neutrophils isolated from animals subjected to sham ischemia and reperfusion (54.3 +/- 4.1 ng/5 x 10(6) PMN; P < 0.01). Pretreatment of animals with the LTB4-receptor antagonist, SC-41930 (n = 5), significantly attenuated reperfusion-associated 5-lipoxygenase activation (60.3 +/- 11.6 ng LTB4/5 x 10(6) PMN; P < 0.01), suggesting the presence of a positive feedback mechanism for eicosanoid biosynthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Iron and cardiovascular dysfunction: mechanisms and therapeutic implications.

It has been recognized for over three decades that tissue hypoperfusion is associated with the appearance of increased levels of iron in the plasma. Experimental observations have documented the liberation of iron into the circulation following reperfusion of ischemic myocardium and small intestine, and into the urine following renal ischemia-reperfusion. Similarly, we have recently demonstrated that iron is delocalized during ischemia of skeletal muscle, via a process which persists upon reperfusion. Other studies have demonstrated delocalization of iron in the parenchyma of postischemic brain, myocardium, and kidney.

Iron delocalization occurs during ischemia and persists on reoxygenation of skeletal muscle.

Attenuation of oxidative reperfusion injury in skeletal muscle by the administration of iron-chelating compounds suggests that ischemia-reperfusion is associated with delocalization of iron with subsequent catalysis of hydroxyl radical generation. To test this hypothesis we examined the extent of iron liberation and lipid peroxidation in a well-established model of high-grade partial hindlimb ischemia and reperfusion. Laparotomy was performed on heparinized male Sprague-Dawley rats with isolation of the infrarenal aorta. Resting membrane potential (Em) and conjugated diene content in hindlimb skeletal muscle were determined along with plasma iron concentration and percent saturation of transferrin in five groups of animals. Baseline animals (n = 6) underwent a 30-minute postoperative stabilization period before data collection; Sham ischemia animals (n = 10) underwent aortic exposure without clamping for 120 minutes; ischemia animals (n = 8) underwent aortic clamping for 120 minutes; sham reperfusion animals (n = 8) underwent aortic exposure without clamping for 150 minutes; reperfusion animals (n = 8) underwent aortic clamping for 120 minutes followed by 30 minutes of reperfusion. Iron delocalization occurred during ischemia, as indicated by a significant rise in percent saturation of transferrin over that of the corresponding sham group (35% +/- 2% vs 25% +/- 2%; p < 0.05) and persisted during reperfusion (39% +/- 5% vs 27% +/- 3%; p < 0.05). Depolarization of resting Em was noted during ischemia (-75.7 +/- 1.7 mV vs - 92.6 +/- 0.4 mV in the corresponding sham group; p < 0.01), with only partial repolarization demonstrated after reperfusion (-82.2 +/- 1.7 mV; p < 0.01 vs all other groups).(ABSTRACT TRUNCATED AT 250 WORDS)