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Biomedical subjects

R B Winter

Publications and source records attributed to R B Winter.

At least 91 records · Page 5Linked to original sources
PubMed1988

Treatment of symptomatic flatback after spinal fusion.

Fifty-five patients who had loss of lumbar lordosis after spinal fusion and subsequently had corrective osteotomies were studied. When they were first seen, fifty-two patients (95 per cent) were unable to stand erect and forty-nine (89 per cent) had back pain. The previous use of distraction instrumentation with a hook placed at the level of the lower lumbar spine or the sacrum was the factor that was most frequently identified as leading to the development of the flatback syndrome. Sixty-six extension osteotomies were performed in these fifty-five patients. Nineteen patients (35 per cent) had an associated anterior spinal fusion. Thirty-three patients (60 per cent) had one or more complications, including pseudarthrosis, a dural tear, failure of hardware, neurapraxia, and urinary tract infection. The results of the operation were evaluated at follow-up by review of clinical records, radiographs, and questionnaires. At an average follow-up of six years (range, two to fourteen years), most patients felt that they had benefited from the corrective osteotomies. However, twenty-six patients (47 per cent) continued to lean forward and twenty patients (36 per cent) continued to have moderate or severe back pain. The failure to restore sagittal plane balance led to a higher rate of pseudarthrosis, which was associated with recurrent deformity. Anterior spinal fusion combined with posterior osteotomy resulted in greater maintenance of correction. The prevention of flatback syndrome is important, since its treatment is difficult. When a spinal fusion must be extended to the level of the lower lumbar spine or the sacrum, the use of distraction instrumentation should be avoided in order to prevent this deformity.

Adolescent↗
PubMed1988

Congenital scoliosis.

Congenital scoliosis, those scoliotic deformities owing to congenitally anomalous vertebrae, was for many years the least understood of the major causes of scoliosis. This was a result of the wide variety of anomalies, the variable natural history, the poor results of bracing, and the meager correction obtained at surgery. The past 20 years have, however, brought major understandings about the natural history and far better programs of treatment. This article provides a summary of these advances for the reader and defines the current state of understanding.

Abnormalities, Multiple↗
PubMed1987

The bacteriophage T4 dexA gene: sequence and analysis of a gene conditionally required for DNA replication.

We have cloned and sequenced a bacteriophage T4 EcoRI fragment that complements T4 del (39-56) infections of an optA defective Escherichia coli strain. Bacteria containing this recombinant plasmid synthesize two new proteins with molecular weights of 9 and 26 kilodaltons. We have identified the gene encoding the 26 kilodalton protein as essential for T4 infections of optA defective E. coli. Genetic and biochemical results are consistent with the identification of this protein as the product of the dexA gene, which encodes a 3' to 5' exonuclease.

Amino Acid Sequence↗
PubMed1987

Bacteriophage T4 regA protein binds to mRNAs and prevents translation initiation.

The bacteriophage T4 regA protein is a translational repressor of a subset of phage mRNAs. We show here that purified regA protein binds specifically to target mRNAs near the initiating AUG and occludes binding of ribosomes. Translational repression by regA protein diminishes expression of many genes whose mRNA sequences around the initiating AUG codons are different. A comparison of nucleotide sequences from several regA-repressed mRNAs suggests that the initiating AUG is an important, but not sufficient, sequence for regA binding.

Base Sequence↗
PubMed1987

Ankylosing spondylitis: experience in surgical management of 21 patients.

Between 1976 and 1984, twenty-one patients with ankylosing spondylitis were treated surgically. Eight patients with rigid thoracic kyphosis underwent a two-stage combined procedure. The average correction was 36 degrees. Eight patients underwent a single-stage lumbar osteotomy with Harrington compression instrumentation. The average correction was 31 degrees. Five patients presented with stress fractures and back pain. All underwent combined anterior and posterior surgery. The average correction was 9 degrees. Two patients underwent anterior decompression for progressive paraplegia. Both showed improvement in neurologic function. At follow-up, all but one patient had improvement in pain and spinal alignment. There have been no deaths or persistent neurologic problems from these procedures.

Adult↗
PubMed1987

Adult idiopathic scoliosis treated by anterior and posterior spinal fusion.

Twenty-six adults, ranging in age from nineteen to fifty-eight years old, were treated for idiopathic scoliosis by two-stage anterior and posterior spinal fusion. The goals of the combined procedure were to increase correction of the curve and decrease the rate of pseudarthrosis. Preoperatively, the major curves measured an average of 83 degrees, and on the best side-bend they averaged 59 degrees, a 29 per cent degree of flexibility. At the time of discharge from the hospital the curves had improved to an average of 44 degrees, a correction of the preoperative curve of 39 degrees or 47 per cent. At an average length of follow-up of forty-nine months, the major curves measured an average of 50 degrees, a 41 per cent correction compared with the initial curves. Twenty-three of the major curves were better than when they were measured on the preoperative radiograph of the best side-bend, by an average of 15 degrees, but eight curves were either the same or worse. No patient had pseudarthrosis or permanent neurological injury. It is our conclusion that a two-stage anterior and posterior fusion is of value for the treatment of the adult who has a rigid curve that requires maximum correction to allow the head, shoulders, and torso to be centered over the pelvis. We do not recommend the use of instrumentation for the anterior fusion as this did not increase the correction of the curve in this series of patients.

Adult↗
PubMed1986

Fusion to the sacrum for nonparalytic scoliosis in the adult.

This study is a retrospective review of 43 adult patients with idiopathic or congenital scoliosis who had spinal fusion from T11 or above to the sacrum. This study was prompted by the frustrations of the treating surgeons in attempting long fusions from the thoracic spine to the sacrum. Of 25 patients treated with a single-stage posterior fusion only 28% had a good result with a single procedure. Failures were due to pseudarthrosis, decompensation, or loss of lumbar lordosis. Ten patients treated with posterior fusion and subsequent 6-month augmentation had a 70% success rate. Eight patients treated with anterior followed by posterior fusion had a 75% success rate. The ideal answer to this clinical problem has not yet been found.

Adult↗
PubMed1986

Pelvic obliquity. Its causes and its treatment.

Pelvic obliquity can be caused by leg length inequality, contractures about the hips, as part of a structural scoliosis, or as a combination of two or more of these causes. Careful physical and radiologic evaluations are necessary to establish the correct diagnosis. Treatment is then directed toward the specific cause, ie, leg length balancing, release of hip contractures, or scoliosis correction. Structural scolioses with pelvic obliquity may be either congenital or paralytic. If a traction roentgenogram reveals the curve to be flexible enough that the pelvis can be fully leveled, then a posterior fusion only is necessary. If the pelvis will not level with traction, then anterior convex wedge excisions (discectomies for the paralytic, hemivertebra excision for the congenital) are necessary for achieving adequate correction. Posterior instrumentation and fusion must follow the anterior procedure. Various forms of internal correction and fixation devices are now available, and there is no single best procedure. Anterior internal fixation devices are being used less and less, while posterior segmental fixation with Luque rods are wires is being used more and more.

Adolescent↗
PubMed1986

Spinal deformities in patients with Charcot-Marie-tooth disease. A review of 12 patients.

Twelve patients with Charcot-Marie-Tooth disease and scoliosis, seven girls and five boys (average age at presentation, ten years), were investigated for an average of 49 months. All but one of the patients were ambulatory. The curve patterns were thoracic in two, thoracolumbar in four, and double thoracic and lumbar curves in six. There was an associated kyphosis in six. Three patients had brace treatment with curve control in two. Four patients underwent posterior spinal fusion with Harrington instrumentation, one with segmental sublaminar wires. Post-operative management consisted of a cast for one patient and a brace for the remaining three. Follow-up period in the surgical patients ranged from 19 to 45 months (average, 32 months). One patient had a superior mesenteric artery syndrome and two had a pseudarthrosis.

Adolescent↗
PubMed1985

Bacteriophage T4 regA protein. Purification of a translational repressor.

The bacteriophage T4 regA protein translationally regulates its own synthesis and the synthesis of several other T4 early proteins. In order to study the mechanism of translational regulation, we have purified the regA protein. Initially a mutant protein, incapable of autogenous repression, was placed under lambda PL transcriptional control and amplified to approximately 10% of total cell protein. The membrane-associated mutant protein was extracted with organic solvent mixtures and purified by reverse phase-high performance liquid chromatography. Polyclonal antibodies prepared against the mutant protein were used in Western blot assays to monitor purification of the wild-type protein from T4-infected cells. Phosphocellulose and poly(U)-agarose chromatography were important steps in its purification. The binding properties of regA protein to polyribonucleotides are discussed in relation to the mechanism by which the protein recognizes its mRNA targets.

Amino Acid Sequence↗
PubMed1985

Spinal arthrodesis for spinal deformity using posterior instrumentation and sublaminar wiring. A preliminary report of 100 consecutive cases.

One hundred consecutive patients with spinal deformity due to various diagnoses were treated by posterior spinal arthrodesis with instrumentation and multiple sublaminar wires. Both the Harrington and Luque rodding systems were used. A total of 1128 wire loops were passed. No patient developed paraparesis or paraplegia, but three had transient sensory disturbance. There were no cases of broken rods or wires. Forty-five of the patients had no postoperative support. This worked well for neuromuscular scolioses, but for idiopathic scoliosis there was a disturbing loss of correction in many cases. Fusion to the sacrum was best accomplished with the "Galveston" technique, other methods having a high rate of pseudarthrosis. The main benefits appeared to be the ability to stabilize neuromuscular patients without the use of external immbolization, and the correction of thoracic lordosis.

Adolescent↗
PubMed1985

Spinal deformities in patients with arthrogryposis. A review of 16 patients.

Sixteen patients with arthrogryposis having spinal deformities were reviewed. The age of diagnosis of scoliosis was from birth to 15 years. Many different curve patterns were seen. Five patients had decreased anterior-posterior thoracic diameter associated with decreasing vital capacity. One of them died at age 6 months of bronchopneumonia and one other at 16 years from cardiac arrest during surgery elsewhere. Eight patients had nonoperative treatment with an orthosis, and of these, three are still under orthotic care. For the remaining five, one had improved at the end of the treatment, and four had increased curvatures in the orthosis. Six patients underwent surgery, four from the group treated by bracing, and two having surgery as the primary treatment at this Center. One patient had posterior fusion without instrumentation, four had posterior fusion with instrumentation, and one had posterior instrumentation without fusion. Spinal problems can occur in arthrogryposis patients, are poorly controlled nonoperatively, and frequently require surgical treatment, especially if there is thoracic lordosis.

Adolescent↗
PubMed1985

Spinal deformities in patients with muscular dystrophy other than Duchenne. A review of 11 patients having surgical treatment.

Eleven patients diagnosed as having muscular dystrophy and who underwent posterior spinal fusion were reviewed: Becker dystrophy in one, limb girdle in two, facioscapulohumeral in one, myopathia unspecified in one, myotonia dystrophica in two, myotonia congenita in one, and hypotonia congenita in three. There were eight females and three males. The curve pattern was thoracic in four, thoracolumbar in three, double thoracic and thoracolumbar in three, and thoracolumbar lordosis in one. Scoliosis was associated with kyphosis in two, with lumbar lordosis in one, and thoracic lordosis in four patients associated with poor vital capacity and shortness of breath. Seven patients had nonoperative treatment, five showing increase of the curve, and two having control of the curve. All patients had posterior spinal fusion with instrumentation with a follow-up of 9-89 months (average, 41 months). Postoperative support was used in all but one. Major complications occurred in four patients: a symptom of vascular obstruction of the duodenum in two, extubation delayed until the 7th day postoperatively in one and pseudarthrosis in one resulting in an increasing curve and refusion. One patient (limb girdle), 6 years after surgery at 21 years died from cardiomyopathy. The second (limb girdle) lost ambulation at age 22 years, 6.6 years after spinal surgery. In conclusion, patients with muscular dystrophies other than Duchenne generally have slowly evolving curves, and the use of an orthosis in the juvenile years controlled the curve until the pubertal growth spurt, when progression occurred. Surgical treatment was successful in stabilizing the deformities.

Adolescent↗
PubMed1985

Molecular cloning of a pIP501 derivative yields a model replicon for the study of streptococcal conjugation.

We have previously constructed a derivative of the broad host range streptococcal plasmid pIP501, a conjugative plasmid designated pVA797, that confers chloramphenicol resistance and contains a unique EcoRI site in a non-essential region of the plasmid molecule. pVA797 (30.7 kb) when cloned in toto as an EcoRI fragment into the positive selection vector pOP203(A2+) gave a recombinant, pVA904 (37.7 kb), which was able to replicate in Escherichia coli and in streptococcal species. It can be phenotypically monitored in either genus by specific drug resistance markers (chloramphenicol resistance in streptococci, tetracycline resistance in E. coli). pVA904 segregates into E. coli minicells where it specifies the production of at least 13 polypeptides. Many of the polypeptides are missing in minicells containing a transfer-defective, deletion derivative of pVA904. pVA904 is an ideal model replicon for the study of streptococcal conjugation because it is a shuttle plasmid thus enabling manipulation using procedures established for E. coli. Specifically, it should be possible to define the genetic basis of streptococcal conjugation by coupling mutagenesis protocols and minicell protein analyses in E. coli with evaluation of transfer function in streptococci.

Bacterial Proteins↗
PubMed1985

The surgical treatment of congenital kyphosis. A review of 94 patients age 5 years or older, with 2 years or more follow-up in 77 patients.

Ninety-four patients with surgical treatment of congenital kyphosis have been reviewed. Of these, 77 had a follow-up of 2 years or more, with an average follow-up of 7 years. The average age at surgery was 15, and the average kyphosis was 75 degrees. Twenty-seven had posterior fusion only, and 48 had combined anterior and posterior fusion. (Two others had anterior fusion only). The average kyphosis in the two groups was the same, but the anterior and posterior group had a better correction and a better maintenance of correction than the posterior group alone. Kyphosis of less than 55 degrees in growing children often was stabilized successfully by posterior surgery only, but adults and patients with kyphosis greater than 55 degrees required both anterior and posterior fusion. Halo-femoral traction was responsible for two of the three paralyses in this review.

Adolescent↗