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Biomedical subjects

S J Blackwell

Publications and source records attributed to S J Blackwell.

At least 19 recordsLinked to original sources
PubMed2001

Altered GLUT1 and GLUT3 gene expression and subcellular redistribution of GLUT4: protein in muscle from patients with acanthosis nigricans and severe insulin resistance.

Multiple isoforms of glucose transporters are found in muscle, the tissue that normally accounts for 85% of insulin-stimulated glucose uptake. Glucose uptake into muscle cells in the fasting state is mediated primarily by GLUT1 and GLUT3 glucose transporters, whereas postprandial (insulin-stimulated) and exercise-related increments in muscle glucose uptake are mediated primarily by GLUT4. To determine if glucose transporters are abnormally expressed in muscle from insulin-resistant subjects, muscle samples were obtained from 10 normal subjects and 6 obese, nondiabetic subjects with severe insulin resistance and acanthosis nigricans. Both GLUT4 total protein and mRNA were normal in the insulin-resistant subjects. Muscle GLUT3 protein and mRNA were lower than controls by 62% and 71%, respectively. GLUT1 mRNA was twice normal, whereas GLUT1 protein content was not significantly increased. GLUT4 protein was markedly redistributed to the muscle plasma membrane in subjects with severe insulin resistance compared with normals (92% v 40% GLUT4 in plasma membrane-enriched fractions, P <.001), whereas the percentage of GLUT1 and GLUT3 protein found in the plasma membrane-enriched fractions was not different from controls. These data document differences in the expression of genes for GLUT1 and GLUT3 in muscle from normal and insulin-resistant subjects. Further, insulin resistance with fasting hyperinsulinemia was associated with a redistribution of GLUT4 to the muscle cell surface with no change in total GLUT4 protein. These data suggest that glucose transporter gene expression and their basal distribution in human muscle are related to insulin resistance and could be determinants of whole body insulin responsiveness.

Acanthosis Nigricans↗
PubMed2001

Palatal fistulas: rare with the two-flap palatoplasty repair.

The purpose of this study was to examine the palatal fistula rate after repair with the two-flap palatoplasty technique. This is a retrospective review of 119 consecutive cleft-palate repairs performed over a 5-year interval by a single surgeon. The two-flap palatoplasty technique was used to provide tension-free, multilayer repairs. The age of these children at the time of repair ranged from 7 to 84 months (mode, 9 months). The initial follow-up visit occurred 2 to 12 weeks after the repair operation (mean, 4 weeks). The postoperative follow-up duration ranged from 7 to 48 months. This review of 119 cleft-palate repairs revealed a fistula rate of 3.4 percent (four fistulas in 119 repairs). This experience demonstrates the lowest reported palatal fistula complication rate with use of the two-flap palatoplasty technique.

Child↗
PubMed2001

Do not use epinephrine in digital blocks: myth or truth?

The purpose of this study was to examine the role for epinephrine augmentation of digital block anesthesia by safely prolonging its duration of action and providing a temporary hemostatic effect. After obtaining approval from the review board of the authors' institution, 60 digital block procedures were performed in a prospective randomized double-blinded study. The digital blocks were performed using the dorsal approach. All anesthetics were delivered to treat either posttraumatic injuries or elective conditions. Of the 60 digital block procedures, 31 were randomized to lidocaine with epinephrine and 29 to plain lidocaine. Of the procedures performed using lidocaine with epinephrine, one patient required an additional injection versus five of the patients who were given plain lidocaine (p = 0.098). The need for control of bleeding required digital tourniquet use in 20 of 29 block procedures with plain lidocaine and in 9 of 31 procedures using lidocaine with epinephrine (p < 0.002). Two patients experienced complications after plain lidocaine blocks, while no complications occurred after lidocaine with epinephrine blocks (p = 0.23). By prolonging lidocaine's duration of action, epinephrine may prevent the need for an additional injection and prolong post-procedure pain relief. This study demonstrated that the temporary hemostatic effect of epinephrine decreased the need for, and thus the potential risk of, using a digital tourniquet (p < 0.002). As the temporary vasoconstrictor effect is reversible, the threat of complication from vasoconstrictor-induced ischemia is theoretical.

Contraindications↗
PubMed1999

Another indication for liposuction: small facial lipomas.

The treatment of facial lipomas at times requires the use of incisions that are less than satisfactory in either size or location. In an effort to minimize scarring, the authors have been removing these lesions with liposuction. The purpose of this study was to review the authors' experience in treating small facial lipomas using liposuction. Over the last 10 years, the authors treated five patients with forehead lipomas by removal with liposuction through hair-bearing scalp incisions. All patients were evaluated after the procedure for bleeding, paresthesias, recurrence, scarring, and overall satisfaction with the procedure. All of these patients had lipomas that measured 4 cm or less at the time of surgery. No patient experienced hematoma, nerve injury, or recurrence. All patients were completely satisfied with their result and scar. The literature describes an advantage to using liposuction for the treatment of medium (4 to 10 cm) and large (>10 cm) lipomas. Because small lipomas (<4 cm) can be extracted through small incisions, the literature reports no advantage to removal with liposuction. However, favorable aesthetic results can be obtained by removing small facial lipomas with liposuction through strategically placed incisions.

Adult↗
PubMed1999

Langer's lines: to use or not to use.

Thirty-six differently named guidelines have developed as surgeons have searched for an ideal guide for elective incisions. Many surgeons prefer Langer's lines. These lines were developed by Karl Langer, an anatomy professor, from cadavers in rigor mortis. However, Kraissl preferred lines oriented perpendicular to the action of the underlying muscles. Later, Borges described relaxed skin tension lines, which follow furrows formed when the skin is relaxed and are produced by pinching the skin. However, these are only guidelines; there are many contributors to the camouflaging of scars, including wrinkle and contour lines. Borges's and Kraissl's lines (not Langer's) may be the best guides for elective incisions of the face and body, respectively.

Anatomy↗
PubMed1998

An emergency multisystem screw removal module.

There are several practical indications for the removal of screws and plates from the reconstructive patient. For the craniomaxillofacial surgeon there exists a wide array of screw and plating systems available. As patients relocate, it is unlikely that individual hospitals have the full collection of rigid fixation systems in their inventory. Therefore, a universal screw removal system was designed to facilitate the elective and emergency removal of all existing craniomaxillofacial fixation hardware. This system is a self-contained module containing a single handle and 12 interchangeable screwdriver blades. The universal screw and plate removal system has been used successfully in several patients--children as well as adults--in whom hardware was removed.

Bone Screws↗
PubMed1998

Creep vs. stretch: a review of the viscoelastic properties of skin.

Possessing viscous and elastic rheological properties, skin is viscoelastic. Mechanical creep, defined as the elongation of skin with a constant load over time beyond intrinsic extensibility, has been described as the vehicle harnessed for wound closure with presuturing, intraoperative tissue expansion, skin-stretching devices, and skin retraction with undermining. Resulting from the generation of new tissue due to a chronic stretching force, biological creep plays a role in conventional tissue expansion.

Biomechanical Phenomena↗
PubMed1998

Epinephrine in digital blocks: revisited.

Digital block anesthesia with epinephrine, ring technique, and digital tourniquet have been implicated in causing finger gangrene. An extensive review of the literature provided no case of finger gangrene attributed solely to the adjunctive use of epinephrine with lidocaine for digital block. By causing vasoconstriction, epinephrine complements the local analgesic by prolonging the duration of action and providing a temporary hemostatic effect. Epinephrine augmentation of digital block anesthesia was used in the treatment of 23 finger injuries without a complication.

Adolescent↗
PubMed1988

Treatment of burn alopecia with tissue expanders in children.

During the past 18 months, 60 tissue expanders were utilized in the reconstruction of 42 children with burn alopecia of the scalp not amenable to a single excision and primary closure at the Shriners Burns Institute in Galveston, Texas. The children were grouped according to the degree of alopecia. All patients with defects of 15 percent or less of the total hair-bearing scalp were able to obtain complete closure of their defects with two operations, i.e., one to place the expander and the second to remove the expander and advance the flaps. Some patients with defects up to 40 percent were closed with serial expansion. Patients with even larger defects had a significant reduction in the percentage of alopecia and benefited from re-creation of anterior hairlines. We have encountered a postoperative complication rate of 10 percent. When compared to previous methods of treating burn alopecia, tissue expansion allows a more rapid closure, fewer operations and coincident anesthetics, and decreased total length of hospitalization.

Adolescent↗
PubMed1988

Cosmetic surgery and criminal rehabilitation.

The contribution of physical appearance to criminal behavior has long been a matter of general interest. We investigated the influence of cosmetic surgery on recidivism rates in the Texas state prison system. The baseline prison population recidivism rates have been 14%, 32%, and 36% at one, two, and three years, respectively. The study group consisted of 253 inmates who had cosmetic procedures between 1982 and 1984 and who were released from prison between the time of operation and the end of 1986. The recidivism rates, calculated by life table analysis, were 8% at one year, 17% at two years, and 25% at three years. All were significantly less than baseline (P less than .01, P less than .001, P less than .01). The rates for those who had been incarcerated for violent crimes were 3.3%, 7.7%, and 15.0% (all P less than .001). We conclude that a positive relationship exists between cosmetic surgery and criminal rehabilitation, as measured by a decrease in recidivism.

Actuarial Analysis↗
PubMed1988

Amniotic band syndrome.

The amniotic band syndrome (ABS) refers to the infrequent occurrence of congenital deformities presumably due to fetal entanglement in strands of ruptured amniotic sac. The most commonly associated anomalies include amputations, constriction bands, syndactyly, craniofacial defects, club feet, and cleft lip. We present a typical case and short literature review of ABS. The infant reported also had a connective tissue nevus and a cutaneous striated muscle hamartoma.

Abdominal Injuries↗
PubMed1987

Routine use of a suction drain in facial rhytidoplasty.

The effectiveness of a suction drain in facial rhytidoplasty was evaluated in 46 women ranging in age from 41 to 78 years. The drain was placed on the left side of the face in 16 and on the right in 14, and no drain was used in 16 patients. The drain was removed in 24 hours regardless of the amount aspirated, which varied between 0 and 25 ml, with an average of 7.8 ml. Although none of these patients developed a hematoma while the drain was in place, a hematoma did occur in 1 patient on the drain side following its removal. Despite the variable quantities of fluid aspirated, there was no clinical difference in swelling noted around the face and neck area when the two sides were compared. Similarly, one could not distinguish this group of patients from those 16 who did not receive the drain. The routine use of continuous suction drains for patients undergoing rhytidoplasty is therefore probably unnecessary.

Adult↗
PubMed1986

Striated muscle hamartoma: description of two cases.

We saw two newborn infants with striated muscle hamartoma. One patient had numerous associated congenital anomalies. The clinical appearance of both lesions was that of a soft fibroma. Histologically, striated muscle fibers and nerve bundles were seen in the central core and also at the periphery of the lesion, below the epidermis. A marked number of sebaceous glands, vellus hair follicles, and eccrine glands were also present. We propose the term striated muscle hamartoma, which points out the most remarkable feature of these lesions.

Hamartoma↗
PubMed1985

Onlay cartilage graft of the alar lateral crus for cleft lip nasal deformities.

The onlay cartilage grafting technique is described for treatment of unilateral or bilateral cleft lip nasal deformities. The alar cartilage is exposed through rim and intercartilagenous incisions. The cephalic half of the alar cartilage is excised, similar to the technique of traditional tip rhinoplasty. The harvested cartilage is applied to the intact caudal cartilage in layered fashion and secured with absorbable sutures. If necessary, successive layers may be added. These grafts provide a sturdy, yet delicate framework for a more normal appearing alar rim. We have performed this procedure on 16 patients, ages 10 to 41. Follow-up intervals range from 13 to 40 months, with a mean of 19 months. Results have been rated good-to-excellent by patients and surgeons. There has been no recurrence of the deformity. The only complication has been one nasal vestibule synechia.

Adolescent↗
PubMed1978

Ten years of experience in managing patients with burn contractures of axilla, elbow, wrist, and knee joints.

An analysis of 625 patients who had sustained burns across the axillae, elbows, wrists, or knee joints indicates that the use of splints and pressure across these joints will not only greatly decrease the incidence of contractures but will also reduce the frequency and need for release operations. However, these appliances must be used for at least 6 months (longer, if possible), if substantial benefits are to be obtained.

Axilla↗
PubMed1978

Migration of silicone gel after the "squeeze technique" to rupture a contracted breast capsule. Case report.

While the squeeze capsulotomy is a simple and effective method for managing capsular contracture around a breast implant, with extreme force the rupture of the prostheses can occur. With the concomitant use of a pressure dressing and breast massage, there was distant migration of the extravasated gel in one case, so this should be considered as a potential complication of this technique.

Breast↗