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L G Phillips

Publications and source records attributed to L G Phillips.

86 records · Page 5Linked to original sources
PubMedDate not supplied

In vivo characterization of interleukin-4 as a potential wound healing agent.

Interleukin-4 increases the synthesis of extracellular matrix proteins, including types I and III collagen and fibronectin, by both human and rat fibroblasts. Because fibroblasts are the final common effector cells of most phases of tissue repair, this study set out to investigate the effects of interleukin-4 on the healing of three different types of wounds. Acute excisional and chronic granulating wounds inoculated with Escherichia coli and incisional wounds in streptozotocin-induced diabetic Sprague-Dawley rats were used. Recombinant murine or human interleukin-4 was applied topically to the open wounds at doses of 0.1, 1.0, or 10.0 microg/cm(2)/wound for 5 or 10 days. Incisional wounds received the same doses once-at the time of wounding. The time taken to achieve wound closure or wound breaking strength measurements of wounds was recorded and compared with relevant untreated control groups. Wound contraction was impaired in the presence of bacteria, and this was reversed by all doses of recombinant murine interleukin-4. Recombinant murine interleukin-4 had no effect on the wound closure of noncontaminated wounds; it reduced wound breaking strength in acute excisional wounds, except in a contaminated setting when wounds were treated with 1.0 pg/cm(2)/wound. Recombinant interleukin-4 (1.0 microg) improved breaking strength of both diabetic and normal incisional wounds. The apparent pleiotropic effect of interleukin-4 on wound breaking strength under different wound conditions may be related not only to the activity of the fibroblast but also the ratio of cross-linked collagen/total collagen content of wounds. This study suggests that interleukin-4 may be a useful agent for accelerating closure of wounds, particularly where healing is impaired.

Journal Article↗
PubMedDate not supplied

Negatively charged beads and transforming growth factor-beta1 stimulate bone repair in rabbits.

Previous studies have shown the osteogenic potential of negatively charged Sephadex beads when used to heal osseous defects in an animal model. The present study examined the effect of adding the growth factors transforming growth factor-beta1 and basic fibroblast growth factor to negatively charged Sephadex beads and neutral (non-osteogenic) Sephadex beads in a critical size calvarial defect in rabbits. New Zealand White rabbits were divided into six groups of five rabbits; 15 mm parietal defects were created and filled with either negatively charged Sephadex beads (three groups) or neutral Sephadex beads (three groups). Each group received either 2 microg of transforming growth factor-beta1, 1 microg of basic fibroblast growth factor, or buffer (control). Animals were killed at 5 weeks, and their calvaria were submitted to plain radiographic and histomorphometric analyses. Defects treated with negatively charged Sephadex beads produced significantly more new trabecular bone than neutral Sephadex beads (p < 0.01), whereas the neutral beads treated with transforming growth factor-beta1 formed significantly more bone than controls. The addition of transforming growth factor-beta1 to negatively charged beads resulted in near closure of the craniotomy defect. The application of transforming growth factor-beta1 to this model resulted in significantly more ectopic bone (p < 0.01) outside the defect on the dural and periosteal surfaces. Basic fibroblast growth factor, in the dose used, appeared to have an inhibitory effect on new bone formation fostered by negatively charged Sephadex beads. This study suggests that the addition of transforming growth factor-beta1 to the known osteoconductive matrix of negatively charged Sephadex beads may be therapeutically useful in nonhealing bony defects.

Journal Article↗
PubMedDate not supplied

The epidemiology of methicillin-resistant Staphylococcus aureus in a burn center.

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in a critical care facility creates a multifaceted epidemiological problem in uncovering the source of infection. This study was undertaken to determine the true etiology of MRSA burn wound infections. Patients with a 30% or greater TBSA burn had both burned and unburned skin surface cultured upon admission, using RODAC plates. All other body fluids were cultured when sepsis was suspected. Admission cultures of 14 patients who developed MRSA wound infections were examined for methicillin-resistant organisms. Both admission isolates and infection isolates were compared by antibiogram analysis. Of the 14 patients admitted who developed MRSA infections, 57.1% of these had methicillin-resistant staphylococci present on admission. However, the remaining 42.9% of the patients had methicillin-sensitive, B-lactamase positive staphylococci present on admission. Isolates of group D streptococci resistant to methicillin were isolated in 35.7% of the patients. This data suggests that burn wound infections caused by MRSA very likely arise from the endogenous flora present at the time of injury through conferring the resistant plasmid by conjugational transfer.

Burn Units↗
PubMedDate not supplied

Inventory of potential reconstructive needs in the patient with burns.

The rehabilitation and reconstruction of patients who survive large burns is an arduous task. To facilitate it we have devised an inventory form to accurately record the somatic abnormalities caused by burns and also the severity and location of burns. This form was used in the assessment of 25 pediatric patients with massive burns. It was found to be a very useful tool that allowed the identification of more specific functional and esthetic deformities than is possible with currently available forms. It also served as a template for the systematic planning of reconstructive procedures.

Burns↗
PubMedDate not supplied

Meshed Biobrane: a dressing for difficult topography.

Biobrane temporary biosynthetic skin substitute has been well demonstrated in the treatment of superficial and deep wounds. We have used this product nearly 1000 times. It has previously been shown to be ineffective for use in areas with convex or concave topographies or in areas along joint surfaces. The following study covers an attempt to adapt this dressing for use in these difficult areas. Ninety-eight applications of meshed Biobrane temporary wound dressing were placed in anatomic locations, which ranged from the head to the foot, with an 86% success rate.

Biocompatible Materials↗
PubMedDate not supplied

Long-term assessment of the effects of circumferential truncal burns in pediatric patients on subsequent pregnancies.

Longitudinal assessment of the long-term effects of pediatric circumferential truncal burns on subsequent pregnancies is poorly documented. Between December 1967 and August 1985, 75 female pediatric patients with circumferential truncal injuries were admitted to our institution. Twenty-two of these patients were available for long-term follow-up into early adulthood. Seven of these 22 patients had conceived. All seven patients had sustained flame-burn injuries. Mean age at injury was 7.66 +/- 2.12 years. Mean total body surface area of burns was 63.21% +/- 16.69%, with 44.21% +/- 17.54% of the injuries full thickness. Each patient was treated with excision and split-thickness skin grafting during initial hospitalization. In the group of seven patients there were 14 pregnancies. All infants were full term. There were 13 vaginal deliveries and one elective cesarean section. Prenatal complications were limited to one case in which a patient had sustained breakdown of scar tissue during the third trimester of pregnancy. There were no labor and delivery complications in this patient population. Circumferential truncal burns appear to have no impact on prenatal or labor and delivery complications.

Adult↗
PubMedDate not supplied

Burn and trauma units as sources of methicillin-resistant Staphylococcus aureus.

At the time that methicillin-resistant Staphylococcus aureus (MRSA) began to achieve clinical prominence, it was thought to be spread by exogenous vectors. Institution of rigorous infection control efforts, including isolation procedures, was found to have little effect on the frequency of MRSA colonization of burn wounds. It was later found that handwashing was sufficient to prevent cross-contamination. Subsequently, it has been shown that patients can be harboring MRSA at the time of admission to the burn unit and that multiple antimicrobial resistance can develop among organisms that reside in the patient through plasmid-mediated transfer of resistance genes. Excessive use of such agents as the synthetic penicillins and second- and third-generation cephalosporins has selected for the survival of these organisms. Currently, the only available agent for systemic treatment of MRSA infection is vancomycin, the use of which is expensive and associated with significant toxicity. Muciprocin is a topical antimicrobial that promises to be useful in the treatment of such infections. Other agents for systemic use are needed, since use of a single drug to combat MRSA infections seems likely to encourage the emergence of resistant organisms.

Burn Units↗
PubMedDate not supplied

Reconstruction of foot burn contractures in children.

Burn scar contractures of the foot cause significant morbidity. We reviewed 68 children in regard to number and rates of burn scar contracture recurrence, surgical techniques, and functional and aesthetic results. Two surgical techniques of foot burn scar contracture release have been used. Originally, an incision over the metatarsal heads perpendicular to the line of the metatarsals, which releases the longitudinal arch of the foot was used. More recently, additional releasing incisions parallel to the plane of the metatarsals to release the transverse metatarsal arch have been used. The time between burn injury and primary burn scar contracture release was 4.18 +/- 0.76 years, and the time until the first recurrence was 3.44 +/- 0.46 years. With release of only the longitudinal arch, recurrence of burn scar contractures occurred in 3.5 +/- 0.41 years and in 4.29 +/- 1.27 years in six patients who also received release of the transverse arch. Wound closure at the time of acute burn with split-thickness skin graft expansion ratios of 1:2 and 1:4 had burn scar contractures that required release in 4.21 +/- 0.70 and 2.29 +/- 0.52 years, respectively.

Burns↗
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A comparison of two different 2400 mOsm solutions for resuscitation of major burns.

The reduction of burn edema is a common goal in the resuscitation of patients with thermal injury. Initial infusion of a 2400 mOsm hypertonic 7.5% NaCl 6% dextran (HSD) has been shown to reduce volume needs, but elevated serum sodium levels limit the dose that can be safely used. This study tested the hypothesis that a 2400 mOsm solution of NaCl, amino acids, glucose, and 6% dextran (Isosal-D) would reduce similar volume requirements while maintaining normal plasma sodium levels. Hemodynamics, plasma sodium, fluid balance, and tissue water content were measured after an initial baseline period and during resuscitation of a large scald injury in 21 anesthetized sheep. Resuscitation was begun 30 minutes after the scald with infusion of 10 ml/kg of either lactated Ringer's (LR), Isosal-D, or HSD and was continued with LR to restore and maintain baseline oxygen delivery throughout the 8-hour period. Oxygen delivery, cardiac output, and mean arterial pressure were rapidly reestablished by all three solutions, although a persistent tachycardia was noted with Isosal-D. Net fluid requirements of both HSD (35 +/- 13 ml/kg) and Isosal-D (72 +/- 13 ml/kg) were significantly lower than in the LR group (203 +/- 39 ml/kg). Mean serum sodium increased 11 mEq with HSD to a peak after 4 hours of 152 +/- 5 mEq, whereas with LR sodium fell 7 mEq to 132 +/- 4. Isosal-treated animals had minimal change in serum sodium. HSD significantly decreased tissue water content in colon, liver, pancreas, and nonburned skin compared with LR, whereas Isosal-D reduced edema only in the colon. It is concluded that in this protocol Isosal-D was not as effective as HSD at reducing volume needs and edema and had unexpected chronotropic effects.

Animals↗
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Much ado about nothing: methicillin-resistant Staphylococcus aureus.

The pathogenic methicillin-resistant Staphylococcus aureus (MRSA) has received a voluminous amount of notoriety. The four major reasons are its morbidity, mortality rate, cost of treatment, and constant appearance in intensive care units. Both Staphylococcus aureus and S. epidermidis (MRSE) account for 82% of our gram-positive wound isolates, whereas the gram-negative account for 34% of all isolates. Therefore we compared the morbidity, mortality rate, and cost factors related to MRSA-MRSE and gram-negative infections for a 4-year period, assessing more than 214 documented infections. Morbidity and mortality rates were minor for MRSA. Pseudomonas aeruginosa and Escherichia coli accounted for 57.5% of the total gram-negative isolates. Gram-negative antimicrobial therapy usually requires two therapeutic drugs, which increases morbidity and costs, whereas the staphylococci usually can be treated by one antimicrobial. During this period there were 47 gram-negative infections requiring 10 to 15 additional days of hospital stay, with a daily antibiotic cost of $293.40. Costs for MRSA or MRSE are 28% less. Therefore our preoccupation with MRSA or MRSE infections is unwarranted and unsubstantiated.

Adolescent↗
PubMedDate not supplied

Trypanosoma manulis n. sp. from the Russian Pallas cat Felis manul.

The morphology of Trypanosoma manulis n. sp. is described from living and stained specimens obtained from the blood of a Pallas cat, Felis manul, from Kazakhstan. The cat was also infected with a Hepatozoon sp. and feline immunodeficiency virus. The morphology of the trypanosome most closely resembles that of Trypanosoma mpapuense Reichenow and Trypanosoma heybergi Rodhain found in bats. Trypanosoma manulis does not grow well in conventional media, but co-culture with African green monkey kidney cells in Eagle's Minimum Essential Medium supplemented with 10% fetal calf serum at approximately 27 degrees C resulted in luxuriant growth of trypanosomes. Under these growth conditions, epimastigotes adhered to the surface of the culture flask and to African green monkey kidney cells, as well as forming large rosettes. At 37 degrees C, although growth was poor, transformation of the epimastigotes into the bloodstream forms occurred. This represents the first report of a trypanosome of the subgenus Megatrypanum in a felid.

Animals↗
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Reconstructive options following mastectomy.

Reconstructive breast surgery is an option a woman may choose following breast loss due to disease, trauma, or congenital malformation. In choosing breast reconstruction a woman must decide on timing and type of procedure. Recent decisions by the Food and Drug Administration have severely limited the type of reconstructive procedure that can be performed. This article discusses all of the options recently available in order to give information to those treating patients who have had these procedures as well as to be encyclopedic in the event that these techniques become available again.

Female↗
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Reconstructive goals for children with burns: are our goals the same?

It is often difficult if not impossible to include a pediatric patient in the planning of burn reconstruction. To give the patient greater input into his or her reconstructive plan, we developed a survey tool to evaluate the different reconstructive goals of the patient, the parent, and the physician. Each patient, parent, and physician were requested to complete a separate goal form. Each form consisted of a simple line drawing of a child that shows both anterior and posterior views. The patient, the parent, and the physician were each asked to circle the desired reconstruction site or sites. The responses were collated and compared by sex, age, size of burn, and evaluator (patient, parent, or physician). Patients indicated fewer and different desired reconstruction sites than the physicians or the parents. Before reconstruction is planned, the patient should be consulted. The desires of the parents and the physician may differ significantly from those of the patient.

Adolescent↗