Toll-like receptor 3 upregulation by type I interferon in healthy and scleroderma dermal fibroblasts

Introduction

Increased levels of genes in the type I interferon (IFN) pathway have been observed in patients with systemic sclerosis (SSc), or scleroderma. How type I IFN regulates the dermal fibroblast and its participation in the development of dermal fibrosis is not known. We hypothesized that one mechanism by which type I IFN may contribute to dermal fibrosis is through upregulation of specific Toll-like receptors (TLRs) on dermal fibroblasts. Therefore, we investigated the regulation of TLR expression on dermal fibroblasts by IFN.

Methods

The expression of TLRs was assessed in cultured dermal fibroblasts from control and SSc patients stimulated with IFNα2. The ability of IFNα2 to regulate TLR-induced interleukin (IL)-6 and CC chemokine ligand 2 production was also assessed. Immunohistochemical analyses were performed to determine whether TLR3 was expressed in skin biopsies in the bleomycin-induced skin fibrosis model and in patients with SSc.

Results

IFNα2 increased TLR3 expression on human dermal fibroblasts, which resulted in enhanced TLR3-induced IL-6 production. SSc fibroblasts have an augmented TLR3 response to IFNα2 relative to control fibroblasts. Pretreatment of fibroblasts with transforming growth factor (TGF)-β increased TLR3 induction by IFNα2, but coincubation of TGF-β did not alter TLR3 induction by IFN. Furthermore, IFNα2 inhibits but does not completely block the induction of connective tissue growth factor and collagen expression by TGF-βin fibroblasts. TLR3 expression was observed in dermal fibroblasts and inflammatory cells from skin biopsies from patients with SSc as well as in the bleomycin-induced skin fibrosis model.

Conclusions

Type I IFNs can increase the inflammatory potential of dermal fibroblasts through the upregulation of TLR3.

Gigantomastia complicating mirror syndrome in pregnancy

BACKGROUND

Gigantomastia is a rare and dangerous condition in pregnancy. Although improvement after delivery is likely, postpartum aggravation is possible. To date, various pharmacological approaches have been tried, with only marginal effectiveness. Surgical intervention is often necessary.

CASE

A young woman presented at 32 weeks' gestation with mirror syndrome and gigantomastia. Two years earlier she had had reduction mammoplasty by free nipple transplant. She delivered by cesarean. Rapid postpartum progression of gigantomastia led to breast necrosis and sepsis. The clinical course was complicated by acute respiratory distress syndrome and renal failure. Emergent bilateral simple mastectomy was performed, with subsequent clinical improvement.

CONCLUSION

When this devastating condition occurs in pregnancy or postpartum, urgent surgical intervention may prevent potentially fatal complications.

Prognostic indicators in the elderly patient with burns

Elderly patients with burns present unique challenges to the burn team. The present study was designed to evaluate the impact of specific preinjury health conditions, mechanisms of injury, and postinjury complications on their survival. A retrospective review of 252 patients more than 55 years of age evaluated demographic information, premorbid medical conditions, burn characteristics, clinical management, complications, and survival during a 12-year period. For comparison, these individuals were divided into four age groups: I (55 to 65), II (66 to 75), III (76 to 85), and IV (86 to 96). Although burn size did not change with age, patients more than 75 years of age experienced a significantly higher mortality rate (60.1%, groups III, IV vs 33.9%, groups I, II, p < 0.05). Preinjury health problems were observed in more than two thirds of the patients, and when two or more were present, there was a higher incidence of complications (65.4% vs 45.3%, p < 0.05) and death (53.0% vs 33.5%, p < 0.01). The effect of premorbid health problems on outcome was most evident in the youngest age group. Prolonged hospital stays and lower survival rates were observed when more than one complication occurred during hospitalization (1 complication, 60.8% survival; 2 or more, 28.0%, p < 0.001). Older age groups more commonly had infections (IV, 76.2%) and a fatal outcome when systemic sepsis occurred (IV, 100%). The lower respiratory tract was the most common site of infection (24.6%) and carried the highest incidence of sepsis (15.1%) and death (13.1%). Certain predictors of poor outcome have been identified in elderly patients with burns, which will aid our treatment of this patient population and facilitate family counselling.

Changing patterns in the epidemiology and treatment of zygoma fractures: 10-year review

A ten year retrospective review of 259 zygoma fractures is presented to highlight changes in epidemiology and treatment. Motor vehicle-related trauma resulted in a majority of the injuries (80.6%), with a high incidence of multiple facial fractures (43.2%). The number of zygomatic and other facial fractures decreased over the duration of the study (by 50.0% and 20.1%, respectively, p < 0.05), perhaps reflecting lowered speed limits and the increased use of seat belts. The proportion of fractures receiving open reduction and internal fixation (ORIF) remained relatively constant (46.3%). At present, miniplate fixation is the preferred surgical treatment, accounting for 61.5% of cases in 1988 and 1989. There was a trend toward the use of multiple fixation sites and more frequent use of the lateral maxillary buttress (20.0% increase over the study period). The need for orbital floor exploration decreased by almost half, possibly reflecting improved preoperative radiologic evaluation. Despite the recent popularity of cranial bone grafting for facial reconstruction, silicone rubber was the preferred material for orbital floor repair (59.6% of cases). Although overall surgical complications were few (1.5%) there was a high incidence of associated ocular injuries (36.3%).

Academic consequences of a trauma system failure

Houston is served by only two trauma centers: Hermann Hospital (University of Texas Medical School at Houston [UTMSH]), and Ben Taub General Hospital (Baylor College of Medicine). In mid-1988, Hermann Hospital, prompted by a shortage of ICU nurses and +8.0 million/yr of uncollectible trauma charges, began to divert critically ill and injured patients to the already overburdened Ben Taub General Hospital. The academic consequences to UTMSH included a severe loss of clinical experience by the surgical residents and medical students and a severe reduction in faculty-generated billing. The lost billing from the trauma service and the other clinical services approximated +8.0 million/yr. This equated to an +13.5 million decrease in the anticipated billings for the year. Alternative revenue sources were not apparent. Other centers with a heavy trauma system commitment are at risk to suffer similar unsettling academic sequelae as our trauma systems fail.

Nasal surgery complications

This study examines the incidence of serious complications in nasal surgery and discusses the diagnosis and management of these complications. The authors review 259 consecutive cases performed between January 1, 1983, and August 31, 1988. One-hundred and ninety-five patients had septorhinoplasties, 29 had septoplasties, and 35 had rhinoplasties. Thirteen of these cases involved serious complications as follows: hemorrhage (5), perforation (4), infections (3), and pneumocephalus (1). All the patients with these serious complications had associated septal and/or turbinate surgery. The diagnosis and management of these complications will be discussed. In this small series of nasal surgery patients, the incidence of serious complications was 5.0 percent, with no fatalities reported. The higher incidence of serious complications occurred when associated septal and/or turbinate surgery was required. Awareness of these complications is essential because of the increasing number of patients presenting to plastic surgeons for nasal surgery in whom associated septal and/or turbinate surgery is necessary.

Timing of burn therapy in the pediatric patient

The physician embarking on the long-term management of burned children must have a very strong and honest relationship with the patient and family or guardians and must use all available resources, including physical and occupational therapists, social workers, and others, over the course of the effort. There is rarely an end-point in the rehabilitation of a burned child, and the surgeon must be aware of the effects of growth, have state-of-the-art knowledge of reconstructive techniques, and ideally have adequate experience to predict the effects of therapy over many years. This experience often can be gained only from senior surgical colleagues who have the advantage of experience following years of observing wounds heal and operations mature. The timing of many facets of pediatric burn care is, in many ways, abstract and based on intense clinical acumen and physical examination. However, it is imperative that the physician develop a treatment timetable based on the principles of contemporary burn care.

Post-trauma reconstruction with free tissue transfer--analysis of 442 consecutive cases

We reviewed 442 consecutive free flaps performed between July 1979 and December 1987 in 423 trauma patients. The ages ranged from 2 to 76 years. There were 339 males and 84 females. Soft-tissue coverage was the most frequent (56.3%) indication, followed by unstable wound, extensive bone loss, chronic osteomyelitis, insensate scar, loss of specialized tissue, and contour deformity. Most of the reconstructed defects (72.4%) were located in the lower extremity and the great majority (42.3%) involved the lower third of the leg. Motor vehicle accidents were the main (45.6%) cause of the defects followed by motorcycle injuries (28.6%), industrial accidents (15.1%), farming accidents (3.6%), and gunshot wounds (3.3%). Seventeen types of free vascularized cutaneous, myocutaneous, muscular, osseous, osteocutaneous, fascial, fasciocutaneous, sensate, and specialized tissue transfers were used. The latissimus dorsi free flap was the most frequently performed tissue transfer. Only 2.3% of the flaps were done within the first 48 hours post-trauma, although 76.5% of the transfers were completed within the first 2 weeks after injury. The overall success rate was 96.4% and the incidence of re-exploration was 14.7%. Free tissue transfers provide a very reliable method for dealing with difficult reconstructive problems in trauma patients.

Primary skin closure in large myelomeningoceles

Numerous reconstructive methods have been described for the soft tissue closure of large myelomeningoceles. Recent advances in techniques of soft tissue expansion provide yet another reconstructive option. Tissue expansion allows for primary closure of the defect with surrounding tissue, resulting in minimal donor site morbidity. This report illustrates the technique of tissue expansion in the closure of a large myelomeningocele.

Structured exercise circuit program for burn patients

A 10-station structured exercise circuit was developed for burn patients. This conditioning program was designed to accelerate overall functional mobility. The effectiveness of this structured exercise program (SEP) was examined with respect to length of hospitalization, number of outpatient occupational/physical therapy visits required over a three-month period following discharge, and number of days required to return to work post-discharge. Results showed no change in hospitalization. There was, however, a significant decrease in the number of outpatient therapy visits required post-discharge and an earlier return to work date for those patients enrolled in the SEP.

Optimal composition of burn resuscitation fluids

The hemodynamic, renal, and hematologic responses to fluid resuscitation with four different hydrating solutions (lactated Ringer's and hypertonic salt solutions, with and without albumin) administered in equal quantities were compared in an ovine burn model. Forty-five animals, including a sham group, were studied. The burn (40%, flame) was inflicted under anesthesia, but the animals were then studied while in the awakened state. Fluid resuscitation was begun one hour after the burn. While all animals survived the burn and disclosed reasonable hemodynamic stability throughout the experiment, those that received lactated Ringer's with albumin (LRA) restored their cardiac output to preburn values, by 24 h postinjury demonstrated higher serum albumin and colloid osmotic pressure levels, experienced no electrolyte or acid-base imbalances, and maintained serum osmolality within normal limits. In contrast to the other solutions, LRA did not induce edema in unburned tissues, and seemed optimal for burn resuscitation.

Managing the difficult airway in patients with burns of the head and neck

A five-phase defined protocol for airway security was developed and administered to a consecutive, selected series of surgical patients with burns to the head and neck that limited their mouth opening or neck mobility. The protocol uses fiberoptic light and scope systems to allow the anesthesia team to visually place the endotracheal tube properly before anesthesia is induced. The technique provides safe, efficient airway management for patients with burns to the head and neck and significantly diminishes patient risks.

Evaluation of a caloric requirement formula in burned children treated with early excision

This study was undertaken to evaluate the effectiveness of a standard caloric requirement formula, as determined by retrospective analysis of weight gain of patients treated by serial debridement, for patients treated by early excision. The caloric intakes of 61 patients with more than 40% third-degree burn, 27 treated with serial debridement of the burn wound and 34 treated with early massive excision, were reviewed and compared to their calculated requirements. Nutritional support in both groups was similar. Of the 48 survivors there was no difference in their age, % TBSA burn, and per cent meeting caloric requirement. The early excision survivors had a greater percentage third-degree burn and weight change but a decreased length of stay. It was concluded that even though the formula, previously developed at our institution, may lead to a slight overestimation in determination of the caloric needs of early excision patients, it is an acceptable means of determining their requirements.

Comparison of serial debridement and autografting and early massive excision with cadaver skin overlay in the treatment of large burns in children

Thirty-two children admitted from 1977 through 1981 were treated by serial debridement of their burn wounds with 1:1.5 to 3:1 meshed autografting of granulating tissue as it became available. Thirty-two burned children treated from 1981 to 1984 were treated by early total excision to fascia with application of 4:1 expanded autograft and cadaver skin for complete closure. The ages (6.8 +/- 0.6 years), sex distribution, and mean per cent third-degree burn (64 +/- 1%) were the same in both groups. There were seven deaths in each group. Overall operating time (10.3 +/- 0.8 hours) and units of blood loss (28.3 +/- 3.5) were indistinguishable in the survivors of both groups. The survivors of the early excision group underwent fewer operative procedures, (5.8 +/- 0.5 vs. 7.6 +/- 0.5) and had a greatly decreased length of hospital stay (57 +/- 5 vs. 97 +/- 8). The ultimate functional and aesthetic consequences of the two techniques must be compared.

Epithelial mediated wound contraction in experimental wounds--the purse-string effect

Wound contraction, a process whereby wound edges are drawn together, is thought to be mediated by the myofibroblast cell population. However, experimental wounds may close as much as 25% (surface area) before the onset of fibroplasia which is marked by the migration of fibroblasts and myofibroblasts into the wound bed 2 to 3 days after injury. This early phase of wound closure appears to be mediated by a contractile force produced by a circumferentially arranged band of fusiform-shaped epidermal cells situated in the wound margin. Cytoplasmic microfilaments in the epidermal cells, similar in size and configuration to actin filaments and/or tonofilaments, are found to be aligned with the long axis of the constitutive cells comprising the contractile band. The data suggest that contraction in experimental wounds is promoted by at least two distinct cell-mediated contractile events: an initial although brief phase effected by cells of the epidermis followed by an extended phase of soft connective tissue contraction produced vis à vis the myofibroblasts in the dermis.

The myofibroblast anchoring strand--the fibronectin connection in wound healing and the possible loci of collagen fibril assembly

Myofibroblast anchoring strands (MAS) are extracellular structures that connect the termini of actin bundles within myofibroblasts to collagen fascicles in the extracellular space of wound healing tissues. The strands appear to be primarily comprised of microfibrils of fibronectin 2-5 nm in diameter. They also embody parallel arrays of intermediary sized filaments (ISF) and an amorphous matrix of collagen. The MAS effectively translate the cellular contractile forces required for cell motility into the collagen filament/fiber deformations required for wound contraction. However, the primary function of the strands appears to be the assembly of ISF into collagen fibrils.

Monitoring, banking, and clinical use of amnion as a burn wound dressing

The preparation of human amniotic membrane obtained from cesarean delivery placentas for use in the treatment of acutely burned pediatric patients is presented. The technique of membrane harvesting and cleansing, bacteriological monitoring during various phases of preparation, and a method of ultracold long-term banking are described. A total of 187 membranes were stripped under aseptic conditions, cultured, treated in 0.025% sodium hypochlorite (NaOCl) for one minute and recultured. Fourteen organisms were recovered prior to NaOC1 treatment, and only 8 organisms after treatment. Amnions that grew any organism after hypochlorite treatment (23%) were deemed unsuitable for clinical use. Clinical experience with amniotic membranes in 36 acutely burned patients suggests that amnion is a cost-effective biological dressing, acceptable as an immediate dressing on superficial second-degree burns. It is also acceptable as an adjunct to meshed autograft over fascia, and as a temporary covering on recently excised wounds prior to autografting.

Surgical management of burn wound sepsis

Twenty-two burned pediatric patients were diagnosed as having wound sepsis confirmed histologically and microbiologically. The availability of histologic and quantitative microbiologic data based upon biopsy data has permitted an early, accurate method of detecting burn wound sepsis. The histologic data have been of greatest value because of their prompt availability and accuracy. All patients underwent tangential debridement or surgical excision to fascia based upon the assessment of the wound by the surgeon. Two patients died at two and five days postoperatively of sepsis attributable to the burn wound. A third patient died at 56 days of sepsis originating at a site other than the burn wound. Thus, the over-all mortality, including the third patient, was 14 per cent. Children surviving the septic episodes showed a marked improvement in the clinical course shortly after undergoing therapeutic surgical excision. Since initiation of surgical intervention in burn wound sepsis, the over-all mortality has decreased from an average annual rate of 11.2 to 2.8 per cent.

An objective method for early diagnosis of gram-negative septicemia in burned children

The present investigation was undertaken to standardize the early diagnosis of Gram-negative septicemia in burned children. Data were collected by means of a matrix which encompassed eight clinical variables routinely monitored by nursing personnel. These variables were evaluated according to their severity using a numerical scale of 0 to 3. A sepsis score was thus calculated for each of 243 burned patients, three times a day throughout their entire hospitalization. Eighty patients with suspiciously high scores (controls) were subjected to a battery of ten laboratory tests aimed at confirming the presence or absence of septicemia. During the 26 months of the study 16 patients (22 episodes) had clinical and laboratory evidence of Gram-negative septicemia. Multiple regression and discriminant analysis techniques were then used to develop statistical models for early diagnosis of septicemia. The two most practical and reliable of these are reported herein. Model I and II would have predicted the diagnosis of sepsis, 83% and 86% of the time, respectively, 1 day before the diagnosis was made using conventional methods. The false positive rates of Models I and II were 7% and 3%, respectively. On the basis of this information it seems possible and rewarding to utilize decision-making charts for monitoring and diagnosis of septicemia.

Ultrastructural evidence for the presence of "fibroclasts" and "myofibroclasts" in wound healing tissues

We have observed, by light and electron microscopy, fibroblast-like cells which appear to be involved in collagen fiber and filament degradation. These cells are most prominent in the dermis of mature hypertrophic scars which were clinically observed to be in the remodeling phase of wound repair. Total incorporation of collagen filaments within cellular vacuoles, as seen by TEM, appears to precede the enzymatic degradation of the collagen. Cytoplasmic contractile bundles and/or collagen filament remnants found within residual lysosomes were also seen in many of these cells. Evidence of structural reorganization within the tissue was observed by means of SEM. These cells appear to be similar to osteoclasts in function: thus we propose to name them "fibroclasts" and "myofibroclasts."

Outpatient breast surgery under intercostal block anesthesia

During the past 3 years, we have performed various breast operations in 320 patients under local anesthesia, using intercostal nerve block. The amount of local anesthetic solution required has been about 20 ml 1% lidocaine for blocking both sides, and an additional 24 ml of 0.5% lidocaine during the surgery. This dosage is well within safe limits. We have found that various breast operations, ranging from augmentation mammaplasty to a staged reconstruction after mastectomy, can be done with this method of anesthesia. The complications attributable to the nerve block were nil in our series.

Late problems in burns

In summary, the commonest late physical complications of the burn injury have been reviewed and an approach to their management described. An understanding of the pathophysiology of the conditions is invaluable in planning one's approach to these problems. The techniques to control and correct chronic wound and hypertrophic scar and contractural deformities have been described. We present only a brief summary of the techniques found most reliable in the management of a large group of burned children over many years.

Management of burns

An overview of the management of the acutely burned patient has been described. Adherence to the sound principles of early resuscitation, appropriate nutrition, wound management, and rehabilitation can provide hope for many of the victims of this tragic injury. Complications encountered throughout the burn illness present unique and perplexing problems for the physician, who must utilize all the clinical wisdom and facility available in the management of such complex problems.