Cutting edge: impaired transitional B cell production and selection in the nonobese diabetic mouse.

Developing B cells undergo selection at multiple checkpoints to eliminate autoreactive clones. We analyzed B cell kinetics in the NOD mouse to establish whether these checkpoints are intact. Our results show that although bone marrow production is normal in NOD mice, transitional (TR) B cell production collapses at 3 wk of age, reflecting a lack of successful immature B cell migration to the periphery. This yields delayed establishment of the follicular pool and a lack of selection at the TR checkpoint, such that virtually all immature B cells that exit the bone marrow mature without further selection. These findings suggest that compromised TR B cell generation in NOD mice yields relaxed TR selection, affording autoreactive specificities access to mature pools.

Conversion Furlow palatoplasty: salvage of speech after straight-line palatoplasty and "incomplete intravelar veloplasty".

INTRODUCTION: The straight-line palatoplasty with intravelar veloplasty (IVVP) is one option for cleft palate repair. However, not all IVVPs are performed uniformly. Many IVVPs only address the medialmost portion of the levator muscle, an "incomplete IVVP," failing to completely dissect and adequately transpose the entire levator muscle, "complete IVVP." We believe that for optimal speech results, IVVPs should completely mobilize and posteriorly displace the levator. We propose that a conversion Furlow palatoplasty performed with a "complete IVVP" will correct postoperative velopharyngeal insufficiency (VPI) and alleviate the need for pharyngoplasty. METHODS: Nineteen patients with postoperative VPI, having had prior straight-line palatoplasty and reported "IVVP," underwent conversion Furlow palatoplasty. Those with a pre- and postoperative Pittsburgh Weighted Speech Scale (PWSS) value and no other history of palatal surgeries were included in this study. Statistical analysis was performed by using the Wilcoxon signed ranks test. RESULTS: Patients' median age was 5.5 years (range, 4-15 years), with 13 males and 7 females. The median preoperative PWSS score was 11.00 (range, 3-24.5), and the median postoperative was 1.00 (range, 0-5) (P < 0.001). All subcategories of the PWSS were also improved. Eight children had a preoperative fistula, and all were successfully corrected. At the time of conversion Furlow palatoplasty, all patients demonstrated no evidence of previous IVVP as the levator muscle was found to be scarred to the posterior edge of the hard palate. CONCLUSION: The conversion Furlow palatoplasty can be used to significantly improve VPI and salvage speech after a straight-line palatoplasty with an "incomplete IVVP." Patients with postoperative VPI should first be considered for conversion Furlow palatoplasty performed with a "complete IVVP" prior to progressing to pharyngoplasty.

Candidate genes for oral-facial clefts in Guatemalan families.

Nonsyndromic cleft lip +/- cleft palate (CL/P) is a complex trait of unknown etiology. Most genetic studies of CL/P define affection status in a way that ignores subtle subclinical manifestations, resulting in a potential loss of statistical power. This study investigated 10 candidate genes in 155 individuals from 25 Guatemalan CL/P families. High-resolution ultrasound images of the orbicularis oris (OO) muscle were obtained. CL/P was present in 28 family members; an additional 10 had subcutaneous OO muscle defects. Family-based association studies were performed for both narrow (CL/P only) and broad (CL/P plus OO muscle defects) definitions of affection status. PVRL1 was significantly associated under both definitions (P = 0.04, narrow; P = 0.02, broad). Association with JAG2 improved from P = 0.09 under the narrow definition to P = 0.04 under the broad definition. Broadening the oral-facial cleft phenotype to include subclinical variants may improve power in genetic studies.

Pectoralis muscle flap reconstruction of pediatric sternal wound infections.

Sternal wound infection (SWI) is a life-threatening complication in both the pediatric and adult population. The morbidity and mortality of SWIs have decreased with the use of muscle flap reconstruction of the chest wall. Although the pectoralis muscle flap is the most frequently used flap in adults for reconstruction after SWI, its use in children has not been well described. To review current experience with the use of the pectoralis muscle flap in a pediatric population, a retrospective review of 1,200 consecutive median sternotomies occurring at the Children's Hospital of Pittsburgh between 1992 and 1997 was performed. All cases of postoperative SWI were identified, and the operative management was performed by a single surgeon. Reconstruction was performed with the use of unilateral or bilateral pectoral muscle flap advancements. Sternal wound infections developed in nine patients (0.75% incidence). The mean duration from initial sternotomy to the time of presentation of deep SWI was 39.5 days. Eight patients underwent reconstruction using pectoralis muscle advancement flaps. Two patients (25%) were reconstructed with a unilateral pectoralis advancement flap, whereas six patients (75%) required bilateral advancement flaps. One patient was treated with conservative management. The average length of stay after reconstruction was 9 +/- 4 days. Duration of follow-up ranged from 3 to 42 months (mean: 16 +/- 12 months). All reconstructions ultimately resulted in well-healed wounds with satisfactory cosmesis. No developmental or functional deficits have been documented in follow-up visits. Sternal wound infection is a serious postoperative complication of median sternotomy. Aggressive operative management with the use of muscle flap reconstruction has helped to lower the morbidity and mortality of this infection. The successful use of pectoralis muscle flap advancement for functional and esthetic reconstruction of the chest wall in children is described.