A 360-kb interchromosomal duplication of the human HYDIN locus

The HYDIN gene located in human chromosome band 16q22.2 is a large gene encompassing 423 kb of genomic DNA that has been suggested as a candidate for an autosomal recessive form of congenital hydrocephalus. We have found that the human HYDIN locus has been very recently duplicated, with a nearly identical 360-kb paralogous segment inserted on chromosome 1q21.1. The duplication, among the largest interchromosomal segmental duplications described in humans, is not accounted for in the current human genome assembly and appears to be part of a greater than 550-kb contig that must lie within 1 of the 11 sequence gaps currently remaining in 1q21.1. Both copies of the HYDIN gene are expressed in alternatively spliced transcripts. Elucidation of the role of HYDIN in human disease susceptibility will require careful discrimination among the paralogous copies.

Canadian multicenter pilot trial of haploidentical donor transplantation

BACKGROUND

Canadian multicenter pilot study of haploidentical donor.

AIMS

To assess (1) ability to collect suitable graft (CD34+ > or = 5 x 10(6)/kg and CD3 < 1 x 10(5)/kg recipient body weight), (2) toxicity, (3) survival to day +100. ELIGIBILITY: All hematological malignancies and ages; accrual to end after 20 transplants of patients with AML in remission and age less than 55 years.

METHODS

Preparation: Modified Perugia regimen, chemotherapy alone; melphalan 140 mg/m2 day -9, thiotepa 10 mg/kg day -7, fludarabine 40 mg/m2 days -7 to -3, and ATG (Thymoglobulin, Sangstat) days -6 to -2 (total 10.5 mg/kg). Infection prophylaxis: Ganciclovir (GC) 5 mg/kg days 5-20 then x5/week until day +100 then x3/week until 210 (subjects 1-3), foscarnet (FC) 90 mg/kg days 4-21 then short course pre-emptive GC or FC (subjects 4-11); fluconazole; cotrimoxazole. Donors: G-CSF 16 microg/kg daily x5 until second pheresis day. T-cell depletion: CliniMACS (MiltenyiBiotec).

RESULTS

Eleven patients with AML have been transplanted from four centers, eight female, three male, median age 34 (range 19-60). Disease status, first CR 1/11, second CR 4/11, third CR1/11, relapse 5/11. Graft CD34+ > or = 5 x 10(6)/kg was achieved in all cases, median 13.72 x 10(6)/kg (Q1, Q3: 8.26, 17.72; min 5.59, max 22.22), and CD3+ was < 1 x 10(5)/kg in all cases, median of 0.49 x 10(4)/kg (Q1, Q3: 0.30, 2.20; min 0.22, max 4.10). Ten of the 11 patients have died, median survival 103.5 days (Q1, Q3: 61.0, 151.0; min 0, max 290.0). Survival to day +100 6/11 (55%). Four patients died of leukemic relapse, six of infection. Of six patients dying of infection, CMV was a definite cause in four. Of four dying with relapse, CMV was significant in one. Engraftment was assessed in 10 patients who survived >0 days. Granulocyte engraftment (> 0.5 x 10(9)/l) was achieved in all patients, median 11.5 days (Q1, Q3: 10, 17; min 8, max 70). Platelet engraftment (> 20 x 10(9)/l) was achieved in 8 of 10 patients, median 15 days (Q1, Q3: 9, 16; min 9, max 97). The two platelet non-engrafters died on days +45 and +61. Toxicity was low, with one toxic death (day 0), and the Bearman organ toxicity gradings were < or = grade 2 in all other patients. There were no instances of graft-vs.-host disease or graft rejection.

CONCLUSIONS

The problems of graft-vs.-host disease and graft rejection have been removed as barriers to haploidentical transplantation but the slow immune reconstitution limits its general application. Late referrals contribute to a high relapse rate and have delayed an optimal evaluation of the procedure.

The sequence and analysis of duplication-rich human chromosome 16

Human chromosome 16 features one of the highest levels of segmentally duplicated sequence among the human autosomes. We report here the 78,884,754 base pairs of finished chromosome 16 sequence, representing over 99.9% of its euchromatin. Manual annotation revealed 880 protein-coding genes confirmed by 1,670 aligned transcripts, 19 transfer RNA genes, 341 pseudogenes and three RNA pseudogenes. These genes include metallothionein, cadherin and iroquois gene families, as well as the disease genes for polycystic kidney disease and acute myelomonocytic leukaemia. Several large-scale structural polymorphisms spanning hundreds of kilobase pairs were identified and result in gene content differences among humans. Whereas the segmental duplications of chromosome 16 are enriched in the relatively gene-poor pericentromere of the p arm, some are involved in recent gene duplication and conversion events that are likely to have had an impact on the evolution of primates and human disease susceptibility.

Late sequelae of septic arthritis of the hip in infancy and childhood

We report a multicenter long-term follow-up study of patients with septic arthritis of the hip during infancy or childhood. Group I ("infantile") consisted of patients with onset before age 3 months, and Group II ("childhood") consisted of patients in whom onset occurred after age 3 months. Patients were specifically examined for this review. Generally, patients at follow-up had poor anatomic appearance radiographically and scored poorly on the Harris rating system. However, pain and activity restriction were minimal. Patients who were not treated operatively tended to function better than patients who underwent operative reconstruction.

Construction of a BAC contig map of chromosome 16q by two-dimensional overgo hybridization

We have used sequence-based markers from an integrated YAC STS-content/somatic cell hybrid breakpoint physical map and radiation hybrid maps of human chromosome 16 to construct a new sequence-ready BAC map of the long arm of this chromosome. The integrated physical map was generated previously in our laboratory and contains 1150 STSs, providing a marker on average every 78 kb on the euchromatic arms of chromosome 16. The other two maps used for this effort were the radiation hybrid maps of chromosome 16 from Whitehead Institute and Stanford University. To create large sequenceable targets of this chromosome, we used a systematic approach to screen high-density BAC filters with probes generated from overlapping oligonucleotides (overgos). We first identified all available sequences in the three maps. These include sequences from genes, ESTs, STSs, and cosmid end sequences. We then used BLASTto identify 36-bp unique fragments of DNA for overgo probes. A total of 906 overgos were selected from the long arm of chromosome 16. Hybridizations occurred in three stages: (1) superpool hybridizations against the 12x coverage human BAC library (RPCI-11); (2) two-dimensional hybridizations against rearrayed positive BACs identified in the superpool hybridizations; and (3) pooled tertiary hybridizations for those overgos that had ambiguous positives remaining after the two-dimensional hybridization. For the superpool hybridizations, up to 236 overgos have been pooled in a single hybridization against the 12x BAC library. A total of 5187 positive BACs from chromosome 16q were identified as a result of five superpool hybridizations. These positive clones were rearrayed on membranes and hybridized with 161 two-dimensional subpools of overgos to determine which BAC clones were positive for individual overgos. An additional 46 tertiary hybridizations were required to resolve ambiguous overgo-BAC relationships. Thus, after a total of 212 hybridizations, we have constructed an initial probe-content BAC map of chromosome 16q consisting of 828 overgo markers and 3363 BACs providing >85% coverage of the long arm of this chromosome. The map has been confirmed by the fingerprinting data and BAC end PCR screening.

Excessive strut wear allowing ball-poppet embolization in a DeBakey-Surgitool aortic valve prosthesis

Excessive cage strut wear allowing ball-poppet embolization caused the sudden death of a 47 year old lady in whom a DeBakey-Surgitool aortic prosthesis had been implanted nine years earlier. Patients with this type of prosthesis should have periodic valvular cine fluoroscopy with image intensification to allow visualization of significant strut wear or fracture, and appropriate prosthetic valve replacement.

A rapid, secure method of sternal closure

In 1977 Robicsek(1) described a method of sternal closure that involved a double wire on each side of the sternum, with appropriate circumferential wires. Shortly thereafter, we modified that procedure, as shown in Figure 1. Only one wire is used on each side of the sternum, and fewer circumferential wires are needed. This type of sternal closure can be performed as rapidly as the usual closure of simple circumferential wire sutures and is much more secure, because the circumferential wires cannot cut through the parasternal wire. After using this method in about 100 patients with either poor sternal bone or chronic lung disease, we have encountered no subsequent sternal separation.

Coronary arterial bypass operations without antibiotic coverage

In this study, six of 693 consecutive patients in 29 months who underwent only myocardial revascularization, without prophylactic systemic therapy with antibiotics, experienced infection of a clean wound. This incidence of infection (0.86 percent) in such patients is the lowest reported in the literature. Prevention of infection of clean mediastinal wounds in patients undergoing only myocardial revascularization is related to preoperative preparation of the skin and local antibiotic irrigation of the wound, rather than to prophylactic systemic therapy with antibiotics.

ASCENDING AORTIC ANEURYSM RESECTION EIGHT MONTHS AFTER TRIPLE CORONARY ARTERY BYPASS: CASE REPORT

This report involves the surgical treatment of a patient who underwent saphenous vein triple coronary artery bypass and subsequently developed an ascending aortic aneurysm and aortic insufficiency. Although the implantation of vascular structures into synthetic grafts is commonplace, this case is unique in that it involves the successful implantation of an aortic island containing the origin of the coronary arteries.

Postoperative chest wound infections in patients requiring coronary bypass. A controlled study evaluating prophylactic antibiotics

A controlled study investigating clean chest wound infections in 904 patients undergoing myocardial revascularization was performed. Four hundred fifty-one patients received systemic antibiotics before and after the operation, and 453 patients received no prophylactic systemic antibiotics. The infection rate was 1.10 per cent and 1.76 per cent, respectively, indicating no statistical difference between the two groups. Preoperative skin preparation and subsequent local antibiotic wound irrigation may be the most important factors in preventing clean wound infection.

Bilateral renal vein and inferior vena cava thrombosis with nephrotic syndrome treated by thrombectomy: case report with 3-year followup

A previously healthy 19-year-old woman taking anovulatory medication presented with symptoms of the nephrotic syndrome and lupus erythematosus. Diagnosis of inferior vena cava and bilateral renal vein thrombosis was made angiographically. The patient was treated successfully by thrombectomy and anticoagulation, and remains well 3 years later. Laboratory data indicate normal renal function and only mild proteinuria. This is the longest followup of a patient with this entity reported in the literature.

Complete obstruction of the left main coronary artery associated with congenital pulmonary valvular stenosis

The surgical treatment of the completely obstructed left main coronary artery is aortocoronary saphenous-vein bypass to the left coronary artery system. Without surgical intervention, this lesion has an exceedingly poor prognosis. This report describes a patient with atherosclerotic obstruction of the left main coronary artery and congenital pulmonary valvular stenosis, an unusual combination of lesions not previously documented together. The patient remains asymptomatic 22 months after aortocoronary saphenous-vein bypass and pulmonary valvotomy.

Traumatic fistula between left anterior descending coronary artery and right ventricle. Case report with successful surgical repair

Twelve traumatic coronary artery-cameral fistulas have been reported in the world's literature. Ten have been secondary to penetrating injuries and two have resulted from blunt chest trauma. This case report involves the successful diagnosis and surgical treatment of a patient with a left anterior descending coronary artery-right ventricular fistula. We also discuss similar arteriocameral fistulas previously reported.

Large anomalous fibrous sac in the right side of the heart

In an adult with atrial septal defect, an unusual conical-shaped fibrous sac resembling a closed windsock occupied the right ventricle and main pulmonary artery. The base of the sac being attached by fibrous strands to the right atrium suggests that the structure is derived from the right valve of the sinus venosus.

The sac is considered to have filled with blood, thereby reducing potential right ventricular diastolic volume.

It is probable that the sac emptied into the right atrium during right ventricular systole, thereby creating a functional state comparable to that of tricuspid insufficiency. Occupation of right ventricular space by the sac established a state somewhat comparable to that in Ebstein's anomaly of the tricuspid valve.