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Biomedical subjects

W L White

Publications and source records attributed to W L White.

At least 91 records · Page 5Linked to original sources

Burns of the ocular adnexa.

Ocular and periocular burns continue to be very complicated problems to manage clinically. Significant contributions have been made over the last year regarding the care and rehabilitation of the patient with this type of injury. N-acetylglucose aminidase activity in burned corneoscleral tissues may prove to be a good clinical indicator to assess the severity of ocular burns. Tenonplasty and split-thickness dermal grafts offer alternatives to conjunctival flaps when the latter is not practical or possible. Split-thickness dermal grafts are useful for treating persistent corneoscleral defects when an environment conducive to free grafts exists. Tenonplasty is a useful procedure in patients with persistent corneoscleral defects in whom no conjunctiva is available and a free graft is not advisable. Oversized soft contact lenses may prove useful in the care of the burn patient predisposed to forniceal foreshortening. An algorithm has been presented to aid in the management of the patient with periocular burns. High-density porous polyethylene can be successfully utilized in the reconstruction of the facial skeleton in burn patients. Useful guidelines have been proposed for the use of tissue expanders in the lower face and neck in pediatric burn patients.

Burns, Chemical↗

Extent of vascularization as a prognostic indicator in thin (< 0.76 mm) malignant melanomas.

Angiogenesis in malignant melanoma (MM) was evaluated by comparing mean vessel number (MVN) in Spitz's nevi (SN), thick and thin MMs that metastasized, and thick and thin MMs with > or = 10-year survival. Vessels were identified with antibodies against factor VIII-related antigen (FVIII) and CD34 in 37 MMs (17 < or = 1.9 mm and 20 > or = 4.0 mm) with > or = 10-year follow-up and 10 SN from children (< or = 9 years old). Fields (x250) with the highest vessel density were counted by independent observers blinded to clinical outcome. There were no differences in MVN between SN versus MMs (P = 1.0), but the distribution of vessels was much more uniform in SN. Seven MM pairs (> or = 5.5 mm) and five pairs (< or = 0.75 mm) were matched by sex, age, site, stage, and primary treatment (paired t-test). In the pairs > or = 5.5 mm, there was no correlation with MVN with either metastasis or death (FVIII P = 0.98; CD34 P = 0.85). Among the thin paired lesions, high MVN (FVIII = 46, CD34 = 39) was significantly related not only to metastasis (FVIII P = 0.04, CD34 P = 0.03) but also to death (FVIII P = 0.04, CD34 P = 0.05). MVN does not separate SN versus MM nor predict outcome in thick (> or = 4.0 mm) MMs; however, high MVN (> or = 42 average) is predictive of metastasis and death in MMs < or = 0.75 mm. Larger matched studies are indicated to confirm this observation.

Adult↗

Production of granulocyte colony-stimulating factor in vitro by monocytes from preterm and term neonates.

We postulated that defective generation of granulocyte colony-stimulating factor (G-CSF) by cells of newborn infants might underlie their deficiencies in upregulating neutrophil production and function during bacterial infection. To test this, we isolated monocytes from the blood of preterm neonates, term neonates, and adults and, after stimulation with various concentrations of interleukin-1 alpha (IL-1 alpha) or lipopolysaccharide (LPS), quantified G-CSF concentrations in cell supernatants and G-CSF mRNA in cell lysates. When stimulated with plateau concentrations of IL-1 alpha for 24 hours, G-CSF concentrations were higher in supernatants of adult cells (8,699 +/- 5,529 pg/10(6) monocytes) than in those from term infants (2,557 +/- 442 pg, P < .05) or from preterm infants (879 +/- 348 pg, P < .05 v adults). When stimulated with plateau concentrations of LPS, supernatants of monocytes from preterm neonates had less G-CSF than did those from term neonates or adults. G-CSF mRNA content was low in cells from preterm infants, higher in those from term infants, and highest in those from adults. On the basis of the in vitro studies, we speculated that serum G-CSF concentrations might be less elevated in neutropenic neonates than in neutropenic adults. Indeed, serum concentrations were relatively low in all nonneutropenic subjects; 92 +/- 34 pg/mL (mean +/- SEM) in 10 preterm neonates, 114 +/- 21 pg/mL in 16 term neonates, and 45 +/- 13 pg/mL in 11 healthy adults. Serum concentrations were not elevated in 7 neutropenic neonates (39 +/- 17 pg/mL) but were in 8 neutropenic adults (2101 +/- 942 pg/mL, P < .05 v healthy adults). Other studies suggested that the lower G-CSF production in neonates is not counterbalanced by a heightened sensitivity of G-CSF--responsive progenitors to G-CSF. Therefore, we speculate that newborn infants, particularly those delivered prematurely, generate comparatively low quantities of G-CSF after inflammatory stimulation, and that this might constitute part of the explanation for their defective upregulation of neutrophil production and function during infection.

Adult↗

Diminished transcription of interleukin-8 by monocytes from preterm neonates.

Developmental delays, which impair antibacterial host defense, are present in the neutrophil system of human preterm neonates. We hypothesized that diminished production of interleukin-8 (IL-8), a neutrophil chemotactic peptide, might in part be responsible for these defects. To test this, monocytes from the blood of preterm neonates, term neonates, and adults were isolated immunologically by "negative panning" and subsequently stimulated with interleukin-1 alpha (IL-1 alpha), tumor necrosis factor alpha (TNF-alpha), or lipopolysaccharide (LPS), after which IL-8 levels in the supernatants were measured by ELISA. Total cellular RNA was extracted and IL-8 mRNA was assessed by Northern blotting and by competitive polymerase chain reaction (PCR) analyses. After stimulation with IL-1 alpha, IL-8 accumulation was lowest in supernatants of monocytes from preterm neonates, intermediate in supernatants of monocytes from term neonates and greatest from monocytes of adults. Similarly, when stimulated with TNF-alpha or LPS, monocytes from preterm neonates produced less IL-8 than cells from term neonates and adults. These differences in IL-8 concentrations paralleled differences in IL-8 mRNA expression.

Adult↗

Cutaneous changes of dermatomyositis in patients with normal muscle enzymes: dermatomyositis sine myositis?

BACKGROUND: Dermatomyositis sine myositis may have various connotations. Controversy exists as to nomenclature, degree of evaluation required, therapy, and course (e.g., does true dermatomyositis of the skin only exist?). OBJECTIVE: The purpose of this study was to assess prospectively patients with the clinicopathologic features of dermatomyositis and normal muscle enzyme serum levels to determine their course in terms of the onset of muscle disease. METHODS: Thirteen patients were studied by complete history and clinical examination, laboratory studies, electromyography, and skin and muscle biopsy. They were observed for 1 to 6 years. RESULTS: Patients were classifiable into three groups: (1) cutaneous changes only, (2) cutaneous changes only at baseline with subsequent development of myositis, and (3) cutaneous changes with normal muscle enzyme serum levels at baseline but with myositis demonstrated by electromyography and/or muscle biopsy specimens. CONCLUSION: Significantly different prognostic and therapeutic implications are present in patients with dermatomyositis with normal muscle enzyme serum levels depending on the results of electromyography, muscle biopsy, and clinical observation.

Adolescent↗

Management of lentigo maligna and lentigo maligna melanoma with paraffin-embedded tangential sections: utility of immunoperoxidase staining and supplemental vertical sections.

BACKGROUND: The use of frozen sections in the management of lentigo maligna and lentigo maligna melanoma has been the focus of some controversy. OBJECTIVE: Our purpose was to utilize paraffin-embedded tangential sections in the management of two cases of lentigo maligna and three cases of lentigo maligna melanoma. METHODS: A modification of Mohs micrographic surgery using rush paraffin-embedded sections with adjunctive immunoperoxidase staining (HMB-45) and supplemental vertical sections was employed. RESULTS: This method resulted in enhanced histologic evaluation of section margins and did not compromise the diagnosis of the primary invasive melanoma or Breslow measurements. CONCLUSION: Mohs micrographic surgery modified by the use of rush paraffin-embedded sections allows adjunctive immunoperoxidase staining and supplemental vertical sections that may be helpful in the management of lentigo maligna and lentigo maligna melanoma.

Aged↗

Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall.

Lipid-laden foamy macrophages are characteristic of xanthogranulomatous pyelonephritis (XGP). We have encountered a case of renal cell carcinoma (RCC), with extensive necrosis, in which confluent sheets of foamy macrophages were a dominant feature. We describe the case and discuss the potential frozen section diagnostic problem in attempting to distinguish between confluent sheets of xanthoma cells a "reactive" change in RCC and xanthoma cells as a fundamental component of XGP. We propose that awareness of that problem should prompt the pathologist to request additional samples.

Aged↗

The spectrum of normolipemic plane xanthoma.

Normolipemic plane xanthoma (NPX) is a well-characterized clinicopathologic entity distinct from necrobiotic xanthogranuloma (NXG). We present the case of a patient with the classic clinical course of NPX but with many histologic features in common with NXG, namely, multinucleated lipophages, cholesterol clefts, and degeneration of collagen with associated cellular necrosis (necrobiosis). We suggest that NPX and NXG represent part of a spectrum of xanthomatous dermal reactions associated with paraproteinemias and may be more closely related than previously recognized.

Aged↗

Self assessment.

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Acquired Immunodeficiency Syndrome↗

Candida endocarditis. A treatable form of pacemaker infection.

Fungal endocarditis is a rare complication of permanent pacemaker implantation. In all reports we have identified, this infection has been fatal, diagnosed postmortem. We present a patient in whom early echocardiographic diagnosis resulted in curative surgical and antimicrobial therapy. Fungal endocarditis is an unusual, but treatable complication of permanent pacemakers.

Candidiasis↗

Differential S100 beta expression in choroidal and skin melanomas: quantitation by the polymerase chain reaction.

PURPOSE: S100 beta, a member of a calcium-binding protein family (S100s), is an important clinical marker for skin melanoma. In contrast, uveal melanomas appeared to express S100 beta protein less frequently and to a lesser degree. This study was performed to verify and extend this finding to the mRNA level. METHODS: A quantitative polymerase chain reaction (PCR)-based method was used. A ratio, comparing the S100 beta PCR fragment to that of beta-actin (an internal reference gene), was generated to compare S100 beta mRNA expression among samples. RESULTS: The ratios for skin melanomas (1.2 to 3.9; three tissues and two cell lines) were significantly higher than that for choroidal melanomas (0.1 to 0.63; seven of eight primary tumors and four of four cell lines). Only one choroidal melanoma biopsy had a ratio greater than 1. The PCR products from choroidal melanoma were identical in size and sequence to the S100 beta, as determined by gel electrophoresis and RNA conformational polymorphism. Because the ratios were also low in choroidal melanoma cell lines, the S100 beta phenotype appears to be genetically stable. CONCLUSION: S100 beta is differentially expressed at the RNA and protein levels by skin and choroidal melanomas, which are derived from distinct populations of melanocytes. However, choroidal melanomas expressing little or no S100 beta were significantly stained by antiserum specific for the S100 protein family. Taken together, these data suggest that choroidal melanocytes express another, perhaps even novel, S100 protein(s).

Actins↗

Absence of human papillomavirus in squamous cell carcinomas of nongenital skin from immunocompromised renal transplant patients.

BACKGROUND AND DESIGN: Human papillomavirus (HPV) is accepted as a factor in the pathogenesis of genital squamous cell carcinomas. The incidences of both HPV infection and squamous cell carcinoma are increased in immunocompromised renal transplantation patients. The purpose of this study was to determine if HPV DNA is present in squamous cell carcinomas of nongenital skin in immunosuppressed patients. Amplification of HPV DNA was performed using the polymerase chain reaction. The sensitivity and specificity of the polymerase chain reaction was assessed on 19 positive and six negative control specimens. Twenty genital squamous cell carcinomas from nonimmunocompromised patients and 28 nongenital squamous cell carcinomas from renal transplantation patients were then analyzed. RESULTS: Human papillomavirus DNA was identified in 18 of 19 positive control specimens and zero of six negative control specimens. Human papillomavirus DNA was identified in four of 20 genital squamous cell carcinoma specimens. In comparison, no HPV DNA was identified in 28 nongenital squamous cell carcinomas from immunosuppressed hosts (Fisher's Exact Test, P < .025). CONCLUSIONS: These findings support a role for HPV in genital skin cancers and suggest that HPV does not play a role in the increased incidence of squamous cell carcinoma in renal transplantation patients.

Carcinoma, Squamous Cell↗

Periparotid lupus erythematosus panniculitis. Clinicopathologic correlation of two cases presenting as primary parotid disease.

Lupus erythematosus (LE) panniculitis, also called lupus profundus, is an uncommon but well-established manifestation of both chronic cutaneous (discoid) LE and systemic LE. Although LE panniculitis characteristically may involve the face, specific parotid and periparotid involvement has not, to the best of our knowledge, been previously reported. We describe the clinicopathologic correlation of two cases of LE panniculitis that presented as apparent primary parotid parenchymal disease; one as a neoplasm, the other as parotiditis. Failure to recognize LE panniculitis resulted in prolonged periods of inappropriate therapy and significant morbidity, including an unnecessary parotidectomy. Lupus erythematosus panniculitis has well-established histologic criteria that should be considered in the differential diagnosis of an unexplained parotid mass.

Adult↗

Congenital oculomotor nerve palsy, cerebellar hypoplasia, and facial capillary hemangioma.

We saw two infants with the unusual combination of oculomotor nerve palsy, facial capillary hemangioma, cerebellar hypoplasia, and apparent gaze palsy. Systematic imaging of children with congenital oculomotor nerve palsy may lead to the recognition of more associated neurologic abnormalities that are not clinically apparent, as was the case in our patients.

Capillaries↗

Arachidonic acid metabolites: effects on inflammation of fetal rabbit excisional wounds.

Uncovered fetal rabbit excisional wounds do not exhibit any classic signs of healing; wounds covered with an impermeable cover do contract, reepithelialize, and exhibit inflammation. Prostaglandin E2 (PGE2) is elevated in amniotic fluid, acting as an immunosuppressant at the maternal-fetal interface. Full-thickness excisional wounds were made on 25-day gestational age rabbit fetuses. Half the wounds were covered with an impermeable cover. Tissue from covered, uncovered, and nonwounded fetuses was examined 72 h after wounding for arachidonic acid metabolites. Uncovered wounds had significantly (P less than or equal to 0.05) elevated levels of PGE2, PGF2 alpha, and 12-HETE versus covered wounds and control tissue. Covered wounds had significantly elevated levels of 15-HETE compared to uncovered and control tissue. The elevated PGE2 in uncovered wounds may act as a fetal immunosuppressant; covered wounds (lower PGE2) developed cellular inflammation. Further investigations of these interactions may permit modulation of adult inflammation.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗