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J Conley

Publications and source records attributed to J Conley.

At least 19 recordsLinked to original sources

Mutant enzymes and tRNAs as probes of the glutaminyl-tRNA synthetase: tRNA(Gln) interaction.

This paper focuses on several aspects of the specificity of mutants of Escherichia coli glutaminyl-tRNA synthetase (GlnRS) and tRNA(Gln). Temperature-sensitive mutants located in glnS, the gene for GlnRS, have been described previously. The mutations responsible for the temperature-sensitive phenotype were analyzed, and pseudorevertants of these mutants isolated and characterized. The nature of these mutations is discussed in terms of their location in the three-dimensional structure of the tRNA(Gln).GlnRS complex. In order to characterize the specificity of the aminoacylation reaction, mutant tRNA(Gln) species were synthesized with either a 2'-deoxy AMP or 3'-deoxy AMP as their 3'-terminal nucleotide. Subsequent assays for aminoacylation and ATP/PPi exchange activity established the esterification of glutamine to the 2'-hydroxyl of the terminal adenosine; there is no glutaminylation of the 3'-OH group. This correlates with the classification of GlnRS as a class I aminoacyl-tRNA synthetase. Mutations in tRNA(Gln) are discussed which affect the recognition of GlnRS and the current concept of glutamine identity in E coli is reviewed.

Base Sequence

Metastatic melanoma to the facial nerve.

Isolated metastatic malignant melanoma to the facial nerve has never been reported. This presentation illustrates a primary melanoma of the helix of the ear that was treated by excisional biopsy and then wedge resection in 1983. The primary melanoma was Clark's level IV and 1.3 mm in thickness. In 1985, a facial paresis slowly developed. There was no gross evidence of recurrent melanoma in the ear or neck, but CT scan showed a mass in the region of the stylo mastoid foramen. A reoperation of the primary site revealed metastatic melanoma in the facial nerve, expanding it to approximately 10 times its normal size. A composite resection was done for the melanoma, and the paralyzed face was immediately rehabilitated by a masseter muscle transfer. The patient received 6000 rads to this area postoperatively and has remained free of disease to date, having returned to his profession as a dentist. A detailed study of all the specimens indicated that this represented a primary metastasis to the facial nerve.

Adult

Is melanoma changing?

Nine hundred ninety-five cases of melanoma of the head and neck were divided into two groups so that certain comparisons could be made concerning the behavior of melanoma over a 55-year period. One hundred twelve melanomas of the ocular system were excluded from this review. The first group consisted of 660 melanomas seen during a period from 1932 to 1972. The second group consisted of 223 melanomas seen during a period from 1973 to 1987. Thirteen parameters, including sex, age, distribution, pre-existing mole, amelanotic melanoma, delay in diagnosis, classification, levels, local recurrence, regional metastasis, systemic metastasis, morbidity, and survival, were studied to assess the behavior and the variations. There is no question that the most important aspect of the favorable changes that have occurred are because of earlier diagnosis and better management by a larger group of well-trained specialists. There are some subtler changes that could possibly indicate biologic alterations, but this requires more time and study to substantiate.

Adolescent

Sternocleidomastoid muscle transfer and superficial musculoaponeurotic system plication in the prevention of Frey's syndrome.

Parotidectomy may be associated with a significant depression in the retromandibular region and a significant incidence of gustatory sweating (Frey's syndrome). Superiorly and inferiorly based sternocleidomastoid flaps and posterior plication of the superficial musculoaponeurotic system were evaluated for their ability to ameliorate both consequences. Sixteen patients with sternocleidomastoid flaps and 16 patients with superficial musculoaponeurotic system plication were compared to a control group of 104 patients. The incidence of Frey's syndrome was 47.1% in the control group, 12.5% (P = 0.025) in the sternocleidomastoid flap group, and 0% (P = 0.005) in the superficial musculoaponeurotic system plication group. The surgical techniques are described. The prevalence of Frey's syndrome is discussed with respect to age, sex, radiation therapy, and the type of parotidectomy performed. The indications and contraindications of the three surgical techniques are described.

Fasciotomy

Squamous cell carcinoma and lingual thyroid.

This report represents the first known case of squamous cell carcinoma associated with lingual thyroid tissue. Clinical examination of an exophytic mass at the base of tongue, CT imaging and a preoperative biopsy established a diagnosis of squamous cell carcinoma of the midline base of tongue. The therapeutic options and management of this carcinoma by surgical resection, irradiation or combined modalities were analyzed. The surgical option was chosen. This was accomplished via a midline labiomandibulo glossal split and primary repair of the wound. The final pathology report revealed a squamous cell carcinoma of the mucosa of the base of tongue directly over a benign lingual thyroid mass. Post-operative thyroid function studies were consistent with hypothyroidism and a thyroid scan confirmed the absence of thyroid tissue.

Aged

Simultaneous 'dual system' rehabilitation in the treatment of facial paralysis.

Simultaneous dual system rehabilitation of facial paralysis involves using two independent reanimation techniques to optimize facial movement in both a quantitative and qualitative manner. These techniques involve the use of nerve grafting or crossover procedures combined with a dynamic muscle transfer. A group of 37 patients who underwent five different combinations of reanimation was analyzed. The techniques were evaluated using a standard rating scheme for judging success of reanimation procedures. The combination of a masseter muscle transfer to the lower region of the face and a cable graft of the upper facial nerve division appeared to offer excellent results in terms of independent motion of the upper and lower regions of the face and good eye closure, while allowing spontaneous mimetic function in 50% of cases. The advantages and disadvantages of the other techniques are described. The clinical situations in which these techniques have advantage over single reanimation techniques are outlined.

Facial Nerve

The melanocyte and melanoma.

This paper reviewed some of the interesting biological aspects of melanocytes and their relationship to the nevus and to melanoma. It also proposed a rationale for "adequate" surgery in the management of melanoma according to level, depth, margins, and trends in treatment. These propositions were derived from an analysis of 995 cases of melanoma of the head and neck.

Head and Neck Neoplasms

Escherichia coli glutaminyl-tRNA synthetase: a single amino acid replacement relaxes rRNA specificity.

We described previously the isolation, by genetic selection, of a mutant of Escherichia coli glutaminyl-tRNA synthetase that misaminoacylates supFtRNATyr with glutamine. The single amino acid change responsible for the mischarging phenotype was identified at amino acid 235 in the translated glnS gene. The mutant, called glnS7, has an Asp----Asn change, and studies with the purified glnS7 gene product show it may mischarge a number of presumably different tRNAs. We have carried out extensive homology searches that show E. coli glutaminyl-tRNA synthetase shares regions of homology with other aminoacyl-tRNA synthetases, although little apparent similarity at the site of the glnS7 mutation. In addition to the conserved 'HIGH' motif implicated in aminoacyl adenylate formation, there are regions of homology of glutaminyl-tRNA synthetase with other synthetases which may be involved in tRNA binding. These include short stretches of homology in sequences acting as a tRNA 'anchor' as well as homology of some aminoacyl-tRNA synthetases to a recently identified motif in ribonucleoproteins. Therefore, our results show that E. coli glutaminyl-tRNA synthetase may share with other aminoacyl-tRNA synthetases regions responsible for tRNA binding, while other regions of the protein, of which the glnS7 mutation may be a component, are responsible for tRNA discrimination.

Acylation

Facial nerve in recurrent benign pleomorphic adenoma.

Improvements in the treatment of benign and malignant tumors in the parotid gland have substantially reduced the incidence of recurrence. This has come about primarily be the abandonment of the enucleation techniques and the development of lateral lobectomy operation. The recurrence rate for benign mixed tumor in the parotid gland is variously reported in the ranges of 0.5% to 10%. Because the benign mixed tumor comprises approximately 65% of the tumors in this gland, this complication assumes an important and specific role. A review of this problem establishes the principles of management, extending from simple reexcision through total parotidectomy with preservation of the facial nerve, and radical parotidectomy with resection of the facial nerve and immediate nerve grafting.

Adenoma, Pleomorphic

Thread augmentation.

A review of thread augmentation has added helpful points to the technique and given an opportunity to assess the long-range results. It is obvious at this stage that there is no panacea for the wrinkling process. Each technique has advantages and disadvantages. The simplicity and low complication rate of thread augmentation supports this appeal. It is reasonable to state that the full application of the concept of this type of augmentation has not as yet been realized with this ongoing principle. This technique has been found of value when used as a single procedure or in combination with blepharoplasty or rhytidectomy.

Biocompatible Materials

Management of the eye socket in cancer of the paranasal sinuses.

There are several basic techniques for obtaining acceptable closure of the orbital defect following exenteration. The approach to reconstructing a socket in the method chosen should be the one that gives the best cosmetic result while not compromising the surgical excision and the possibility of cure. Few surgeons have attempted to correct the deformity of orbital exenteration so that an artificial eye can be worn. We have found that approximately 20% of those patients undergoing radical ablation of the orbit quality for simultaneous reconstruction of the eye socket. The technique of a cheek-eyelid-conjunctiva flap allows for immediate reconsturction of the eye socket and the fitting of a prosthesis.

Eye, Artificial

Surgical treatment of hypopharyngeal stenosis in children.

Five cases are presented of severe scarring, in the hypopharynx in children, which did not respond to conservative measures. These patients were treated by excision of the scar tissue and reconstitution of the area by Z-plasty, local mucosal flaps, regional chest flaps and colon transfer depending upon the severity of the problem. All had rehabilitation undertaken of the structural integrity of deglutive, respiratory, and vocal mechanisms. It is recommended that in this type of problem early rehabilitation is warranted rather than subjecting the child to prolonged gastrostomy and tracheotomy into puberty. When extended, the morbidity has a physical and psychological affect on these children.

Child

Sublabial approach to the nasal and nasopharyngeal cavities.

A sublabial transnasal degloving approach to the mid-face, nasal cavity, septum, paranasal sinuses, and nasopharynx is described. This approach provides adequate exposure and ample facility for management of tumors in these areas. The pterygomaxillary space and infratemporal fossa ard readily accessible for hemostasis and management of tumor extensions. Children, adolescents, and women with benign and low-grade malignant tumors of these areas are the ideal candidates for this procedure. Twenty-six patients have been managed in this fashion, with no major complication. The cosmetic results have been excellent. This approach to the mid-third of the face, nasal, paranasal, and nasopharyngeal cavities should receive more attention and use.

Adolescent

Thread augmentation for facial rhytides.

Thread augmentation, a subsurface technique for correcting facial rhytides, is especially applicable to perioral wrinkles, melolabial furrows, and frown lines about the forehead. It is basically an augmentation technique which places a volume of well-tolerated, slowly absorbable or nonabsorbable sutures underneath the wrinkle. These threads produce augmentation by their volume and the mild local reaction of edema, lymphocytic infiltration, and fibrosis. This process gradually progresses to internal scar formation as the suture material is dissolved by slow hydrolysis in the presence of tissue fluid over a period of months; the nonabsorbable suture remains as a permanent implant. A high level of patient satisfaction with minimal complications has proved the value of this technique in over 100 cases.

Absorption

Surgical approach to retromandibular parotid tumors.

Because of the anatomy of the deep lobe of the parotid and its restrictive boundaries, retromandibular tumors may be asymptomatic until reaching massive size. Removal by an intraoral approach may be not only disappointing but also disastrous, with disintegration of the tumor and generalized spillage in the wound. Our experience suggests that the best approach to any type of tumor in this region is through the upper lateral cervical tissues with consideration of a mandibular osteotomy if the tumor extends into the retropharynx or the nasopharynx. This review of 12 patients who required osteotomy describes a high success rate with minimal complications.

Adenoma, Pleomorphic

Hypoglossal-facial nerve anastomosis for reinnervation of the paralyzed face.

The hypoglossal-facial nerve crossover is a valuable surgical procedure for the treatment of certain types of facial paralysis. It is most effective when used as an integral part of a primary ablative operation for the treatment of cancer in this region. In the treatment of long-standing facial paralysis, its application requires an intact peripheral facial nerve system and some functioning mimetic muscles with an obliterated proximal facial nerve segment. It is recognized that other procedures are available for repair in patients who meet essentially these same criteria. The disadvantages are minimal intraoral crippling, mass movements of the face and, in some instances, hypertonia of the face. The advantages are improved facial tone, protection of the eye, intentional facial movements controlled by the tongue, and movements associated with physiological functions of the tongue.

Adolescent