Estimation of carcass composition using rib dissection of calf-fed Holstein steers supplemented zilpaterol hydrochloride

A serial harvest was conducted every 28 d from 254 to 534 d on feed (DOF) to quantify changes in growth and composition of calf-fed Holstein steers (n = 115, initial body weight (BW) = 449.2 ± 19.9 kg). One-half were supplemented with the β-2 adrenergic agonist zilpaterol hydrochloride (ZH; 8.33 mg/kg 100% dry matter (DM) basis) during the final 20 d followed by a 3-d withdrawal prior to harvest; the remainder was fed a non-ZH control (CON) ration. Five steers were randomly selected and harvested after 226 DOF which served as a reference point for modeling purposes. Fabricated carcass soft tissue was ground, mixed, and subsampled for proximate analysis. Moreover, following the traditional method of rib dissection which includes the 9th, 10th, and 11th rib contained within the IMPS 103 primal, the relationship of carcass chemical composition to 9-10-11 rib composition was evaluated. Carcasses in this investigation had more (P < 0.01) separable lean, fat, ash, and moisture concomitant with less bone and ether extract than rib dissections. However, protein levels were similar (P = 0.27) between carcasses and rib dissections. Using regression procedures, models were constructed to describe the relationship of rib dissection (RD) composition including separable lean (RDSL), separable fat (RDSF), separable bone (RDSB), ether extract (RDEE), protein (RDP), moisture (RDM), and ash (RDA) with carcass composition. Carcass lean (CL), carcass fat (CF), and carcass bone (CB) were correlated (P < 0.01) with RDSL, RDSF, and RDSB with simple r values of 0.41, 0.71, and 0.50, respectively. Chemical composition of the rib and carcass, carcass ether extract (CEE), carcass protein (CP), carcass moisture (CM), and carcass ash (CA) were correlated (P ≤ 0.01) with simple r values of 0.75, 0.31, 0.66, and 0.37, respectively. Equations to predict carcass fatness from rib dissection variables and ZH supplementation status were only able to account for 50 and 56%, of the variability of CF and CEE, respectively. Overall, the relationships quantified and equations developed in this investigation do not support use of 9/10/11 rib dissection for estimation of carcass composition of calf-fed Holstein steers.

Objective biometric measurements of calf-fed Holstein steers fed in confinement

Understanding the maximum slaughter size for calf-fed Holstein steers based on hip-height has become a contemporary issue in the beef processing industry. Increased carcass size, in terms of both weight and length, has outpaced the ability of some abattoirs to handle the larger animals. Moreover, some abattoirs have begun rejecting animals that exceed 147.3 cm (58 inches) at the hip, creating a challenge for Holstein cattle feeders. The objective of this study was to quantify the skeletal growth rate of calf-fed Holstein steers fed in confinement. Hip-height of calf-fed Holstein steers ( ≤ 135) was measured every 28 d from 226 to 422 d on feed. Hip-height was a dependent variable modeled via linear regression procedures utilizing days of age and BW as independent variables. Additionally, logistic regression was used to estimate the probability of a steer exceeding a hip-height of 147.3 cm (58 inches) from independent variables of days of age and BW. The linear relationship of BW to hip-height had an adjusted value of 0.7112 (Hip-height, cm = [0.0593 × BW, kg] + 109.00) and on average the calf-fed Holstein steers grew 1.0 cm for each 16.9 kg of BW gain during the finishing phase. The 10%, 50%, and 90% probability of a steer exceeding 147.3 cm (58 inches) of hip-height was achieved at 563, 653, and 743 kg of BW, respectively. The linear relationship of days of age to hip-height had an adjusted value of 0.6687 (Hip-height, cm = [0.0937 × days of age] + 104.4) and the calf-fed Holstein steers grew 1.0 cm for each 10.7 d of age during the finishing phase. The 10%, 50%, and 90% probability of a steer exceeding 147.3 cm (58 inches) of hip-height was estimated to occur at 408, 459, and 510 d of age, respectively. Knowledge of Holstein steer growth rate in relation to BW and age may allow for more accurate sorting to prevent oversized cattle arriving at the abattoir and subsequent discounts or being rejected for slaughter.

Fabrication yields of serially harvested calf-fed Holstein steers fed zilpaterol hydrochloride

Holstein steers ( = 110) were fed zilpaterol hydrochloride (ZH) for 0 or 20 d before slaughter during a 280-d serial harvest study. Cattle were harvested every 28 d beginning at 254 d on feed (DOF) and concluding at 534 DOF. After slaughter, carcasses were chilled for 48 h and then fabricated into boneless closely trimmed or denuded subprimals, lean trim, trimmable fat, and bone. Inclusion of ZH increased cold side weight (CSW) by 10.3 kg ( < 0.01; 212.7 vs. 202.4 kg [SEM 1.96]) and saleable yield by 10.4 kg ( < 0.01; 131.9 vs. 121.5 kg [SEM 1.16]) in calf-fed Holstein steer carcasses. Additionally, saleable yield as a percentage of CSW increased ( ≤ 0.01) by 2.19% (62.64 vs. 60.45% [SEM 0.22]) for cattle supplemented with ZH. Subprimal weights were heavier ( ≤ 0.05) from cattle that received ZH except for the bottom sirloin ball tip, back ribs, and outside skirt regardless of slaughter endpoint. Yield of top round, bottom round, and knuckle was increased ( ≤ 0.01) following ZH supplementation by 0.37, 0.24, and 0.18%, respectively. Yield of the top sirloin butt, strip loin, and tenderloin was increased ( ≤ 0.01) concurrent with ZH supplementation by 0.18, 0.11, and 0.09%, respectively. Regarding the rib primal, the rib eye roll tended ( = 0.08) to had increased yield (2.80 vs. 2.72% [SEM 0.03]) with ZH supplementation; both back ribs and blade meat exhibited increased ( ≤ 0.04) yields of 0.04%. Relative to the chuck primal, increased ( ≤ 0.03) yields of shoulder clod, pectoral meat, and mock tender were observed (0.13, 0.07, and 0.04%, respectively). Yield changes for subprimal brisket, plate, and flank were limited to increased ( < 0.01) proportion of flank steak and elephant ear (cutaneous trunci), 0.07 and 0.04%, respectively. Feeding duration notably altered ( ≤ 0.01) weights and percentages of all subprimals except the brisket. Saleable yield increased ( ≤ 0.01) by 0.192 kg/d with additional DOF. Moreover, trimmable fat and bone increased ( ≤ 0.01) by 0.146 and 0.050 kg/d, respectively. These data illustrate improved saleable meat yields for calf-fed Holstein steers supplemented with ZH and provide the beef industry knowledge of fabrication yield changes throughout a wide range of harvest endpoints.

The effect of days on feed and zilpaterol hydrochloride supplementation on feeding behavior and live growth performance of Holstein steers

This experiment was designed to study the effect of days on feed (d 225-533) and zilpaterol hydrochloride (ZH) supplementation on Holstein steer ( = 110) performance and feeding behavior as part of a serial slaughter trial. Steers were randomly assigned to 1 of 11 harvest groups with 10 steers ( = 5 control and = 5 ZH; ZH at 8.33 mg/kg diet) harvested each 28 d. Steers were weighed every 28 d (d 225, 253, 281, 309, 337, 365, 393, 421, 449, 477, 505, and 533); individual daily meal consumption data for each steer were recorded using GrowSafe technology. In the pretreatment period, dry matter intake expressed a negative quadratic relationship with days on feed (DOF) {DMI = -5.7120 + (0.08370 x DOF)- (0.00011 x DOF); Adj. = 0.2574; RMSE = 0.25 75; 0.01}. A linear increase in BW ( < 0.01) occurred during the pretreatment 308 d period from 466 to 844 kg, {BWend = 137.61 + (1.4740 x DOF); Adj. = 0.8819; RMSE = 37.06; < 0.01}, whereas ADG and G:F decreased linearly. Dry matter intake per meal exhibited a quadratic relationship over days on feed and peaked ( < 0.01) during d 365 to 392 at 1.065 kg coinciding with the highest numerical daily DMI (11.19 kg). Daily consumption visit duration differed ( < 0.01) during the 308 d period, with a low of 52.29 min (d 337-364) and a high of 55.59 min (d 365-392). Consumption rate peaked at 714 g/min (d 337-364) and exhibited a quadratic relationship to DOF. The difference ( < 0.04) in DMI between control and ZH treated cattle across all 11 harvest groups averaged 0.575 kg. Moreover, ZH treatment resulted in decreased ( 0.01) DMI per meal event of 0.093 kg. Gain to feed tended to improve ( = 0.06) with ZH treatment by 0.017 kg gain per kg feed relative to the control cattle. Daily bunk, consumption, and meal visit durations were influenced by ZH during the 20 d treatment period ( = 0.01); the average difference between control and ZH supplemented cattle over the 308 d trial was 9.09, 8.71, and 11.39 min per d, respectively. The data collected in this trial indicate live growth performance and feeding behavior were impacted by both DOF and ZH supplementation.

Byproduct yields of serially harvested calf-fed Holstein steers fed zilpaterol hydrochloride

A 2 × 11 factorial treatment structure was applied in a completely randomized experimental design to investigate differences in noncarcass tissue among serially harvested Holstein steers. Steers ( = 110) were randomly assigned to 1 of 2 dietary treatments: a ration supplemented with zilpaterol hydrochloride (ZH) fed at a rate of 8.3 mg/kg DM for 20 d followed by a 3-d withdrawal or a control ration with no ZH included in the diet. Within treatment, steers were assigned to harvest groups of 254, 282, 310, 338, 366, 394, 422, 450, 478, 506, or 534 d on feed (DOF) prior to initiation of the trial. Cattle fed ZH realized an empty BW (EBW) increase ( ≤ 0.03) of 2.8% (644.2 vs. 626.4 kg [SEM 5.4]) and a HCW increase of 5.0% (429.1 vs. 408.4 kg [SEM 4.0]) with a concomitant 12% reduction (45.1 vs. 51.2 kg [SEM 3.1]) in gastrointestinal contents and 2.1 percentage unit increase in dressed carcass yield (62.1 vs. 60.0% [SEM 0.01]). Additionally, ZH supplementation decreased (P ≤ 0.03) the absolute weight of the liver and kidneys by 0.3 and 0.1 kg, respectively. When noncarcass components were expressed on an empty body basis (g/kg EBW), reductions ( ≤ 0.01) in the limbs (18.8 vs. 19.5 g/kg EBW [SEM 0.1]), hide (81.1 vs. 78.1 g/kg EBW [SEM 0.7]), liver (14.2 vs. 13.2 g/kg EBW [SEM 0.2]), kidneys (2.6 vs. 2.3 g/kg EBW [SEM 0.04]), small and large intestines (74.9 vs. 69.6 g/kg EBW [SEM 1.2]), and gastrointestinal tract (119.8 vs. 113.4 g/kg EBW [SEM 1.3]) were observed with ZH supplementation. Additionally, there was a tendency ( = 0.07) for the proportion of total offal to be reduced (253.2 vs. 247.4 g/kg EBW [SEM 2.5]) with ZH supplementation. Empty BW and HCW linearly increased ( < 0.01) by 1.16 and 0.758 kg/d ( < 0.01), respectively, with additional DOF. The weight of the liver and intestines linearly increased ( < 0.01) by 0.007 and 0.133 kg/d ( < 0.01), respectively, with additional DOF. These data indicate the magnitude of change in noncarcass tissues that can be expected when calf-fed Holstein steers are supplemented with ZH.

Carcass grading characteristics of serially harvested calf-fed Holstein steers fed zilpaterol hydrochloride

Serial harvests were conducted using Holstein steers ( = 110) fed zilpaterol hydrochloride (ZH) for 0 or 20 d prior to harvest. Steers were harvested in 28-d increments beginning at 254 d on feed (DOF) and ending at 534 DOF. After harvest and a 36-h chill period, carcasses were evaluated using grading methods standard for the United States (USDA), Canada (Canadian Beef Grading Association [CBGA]), and Japan (Japanese Meat Grading Agency [JMGA]). No ZH treatment differences ( = 0.81) were detected for 12th-rib fat thickness; however, additional DOF resulted in a daily linear increase ( < 0.01) of 12th-rib fat thickness by 0.004 cm/d. Longissimus muscle area was increased ( < 0.01) by 8.7 cm with ZH supplementation and linearly increased ( < 0.01) 0.08 cm2/d with additional DOF. Calculated USDA yield grade (YG) decreased ( < 0.01) 0.33 units due to ZH treatment and linearly increased ( < 0.01) 0.009 units/d. Steers supplemented with ZH exhibited increased ( < 0.01) CGBA LM width; however, no difference ( = 0.37) was detected in CGBA LM length. No ZH treatment differences ( = 0.64) were observed for CBGA fat class; however, CGBA fat class linearly increased ( < 0.01) by 0.01 units/d. No ZH differences ( ≥ 0.17) were detected for the CBGA estimated lean percentage or YG equations. Evaluation for JMGA occurs at the sixth and seventh rib interface; LM area was 4.6 cm2 greater ( = 0.02) for cattle supplemented with ZH and linearly increased ( < 0.01) by 0.07 cm2/d with additional DOF. Subcutaneous fat thickness was not different among ZH treatments ( = 0.10) but linearly ( < 0.04) increased ( < 0.01) by 0.005 cm/d with additional DOF using the JMGA grading method. No difference ( ≥ 0.21) was calculated between ZH treatments or DOF for JMGA estimated yield. No ZH treatment differences ( = 0.85) were detected in USDA marbling score; however, marbling linearly increased ( < 0.01) 0.07 units/d. These data illustrate the impact of ZH and increasing DOF on economically important carcass grading outcomes used in the USDA, CBGA, and JMGA grading programs.

Management of dental complications in a child with rhabdomyosarcoma

Radiotherapy treatment options can cause adverse dental sequelae, including xerostomia, dental radiation caries, abnormal tooth development, and osteoradionecrosis (ORN). Hyperbaric oxygen (HBO) therapy can be used prophylactically or therapeutically to treat or reduce the risk of ORN. The purpose of this paper was to describe a case involving a 5-year-old male with rhabdomyosarcoma of the left temporal fossa and a history of radiation therapy who presented with gross radiation caries and xerostomia. Full-mouth extractions of all primary teeth were performed under general anesthesia, with the patient receiving HBO therapy before and after the surgery. The child was monitored postoperatively, and healing occurred with minimal post-operative complications. Based on his results, it can be concluded that hyperbaric oxygen therapy is an effective supplement to consider when treating children who have undergone radiation therapy and require dental care.

Effect of polymer deposition method on thermoresponsive polymer films and resulting cellular behavior

Poly(N-isopropyl acrylamide) or pNIPAM is a thermoresponsive polymer that is widely studied for use in bioengineering applications. The interest in this polymer lies in the polymer's unique capability to undergo a sharp property change near physiological temperature, which aids in the spontaneous release of biological cells from substrates. Currently, there are many methods for depositing pNIPAM onto substrates, including atom-transfer radical polymerization (ATRP) and electron beam ionization. Each method yields pNIPAM-coated substrates with different surface characteristics that can influence cell behavior. In this work, we compare two methods of pNIPAM deposition: plasma deposition and codeposition with a sol-gel. The resulting pNIPAM films were analyzed for use as substrates for mammalian cell culture based on surface characterization (XPS, ToF-SIMS, AFM, contact angles), cell attachment/detachment studies, and an analysis of exocytosis function using carbon-fiber microelectrode amperometry (CFMA). We find that although both methods are useful for the deposition of functional pNIPAM films, plasma deposition is much preferred for cell-sheet engineering applications because of the films' thermoresponse, minimal change in cell density, and maintenance of supported cell exocytosis function.

Assignment of two loci for autosomal dominant adolescent idiopathic scoliosis to chromosomes 9q31.2-q34.2 and 17q25.3-qtel

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is the most common form of spinal deformity, affecting up to 4% of children worldwide. Familial inheritance of AIS is now recognised and several potential candidate loci have been found.

METHODS

We studied 25 multi-generation AIS families of British descent with at least 3 affected members in each family. A genomewide screen was performed using microsatellite markers spanning approximately 10-cM intervals throughout the genome. This analysis revealed linkage to several candidate chromosomal regions throughout the genome. Two-point linkage analysis was performed in all families to evaluate candidate loci. After identification of candidate loci, two-point linkage analysis was performed in the 10 families that segregated, to further refine disease intervals.

RESULTS

Significant linkage was obtained in a total of 10 families: 8 families to the telomeric region of chromosome 9q, and 2 families to the telomeric region of 17q. A significant LOD score was detected at marker D9S2157 Z(max) = 3.64 ( theta= 0.0) in a four-generation family (SC32). Saturation mapping of the 9q region in family SC32 defined the critical disease interval to be flanked by markers D9S930 and D9S1818, spanning approximately 21 Mb at 9q31.2-q34.2. In addition, seven other families segregated with this locus on 9q. In two multi-generation families (SC36 and SC23) not segregating with the 9q locus, a maximum combined LOD score of Z(max) = 4.08 ( = 0.0) was obtained for marker AAT095 on 17q. Fine mapping of the 17q candidate region defined the AIS critical region to be distal to marker D17S1806, spanning approximately 3.2 Mb on chromosome 17q25.3-qtel.

CONCLUSION

This study reports a common locus for AIS in the British population, mapping to a refined interval on chromosome 9q31.2-q34.2 and defines a novel AIS locus on chromosome 17q25.3-qtel.

Case-mix fails to explain variation in mastectomy rates: management of screen-detected breast cancer in a UK region 1997-2003

Wide variation in the surgical management of breast cancer exists at hospital, regional, national and international level. To demonstrate whether variation in surgical practice observed at aggregate level between breast units persists following adjustment for case-mix, individual patient-level data from the Trent Breast Screening Programme Quality Assurance database (1997–2003) was analysed. Expected case-mix adjusted mastectomy rates were derived by logistic regression using the variables tumour size, site and grade, patient age and year of presentation, employing the region's overall case-mix adjusted practice as the reference population. The region's 11 breast screening units detected 5109 (3989 invasive) surgically managed primary breast cancers over the 6-year period. A total of 1828 mastectomies (Mx) were performed (Mx rate 35.8%, 95% confidence interval: 34.5–37.1%). Significant variation in mastectomy rates were observed between units (range 25–45%, P<0.0001), and persists following case-mix adjustment (P<0.0001). Two-fold variation in observed to expected unit mastectomy rate coefficient is demonstrated overall (range 0.66–1.36), increasing to almost four-fold variation in cancers less than 15 mm diameter (range 0.55–1.95). Significant variation in surgery for screen-detected primary breast cancer is not explained by case-mix. Further research is required to investigate potential patient and professional causative factors.

Carcinoma with thymus-like differentiation arising in the dermis of the head and neck

Carcinoma exhibiting thymus-like differentiation (CASTLE) is a rare, distinct tumor of the thyroid gland or soft tissue of the head and neck that may simulate primary squamous cell carcinoma or lymphoepithelioma, and which contains features reminiscent of thymic differentiation including Hassall's corpuscles, occasional perivascular spaces, and the presence of lymphocytes. Ectopic thymic tissue may result from incomplete descent or persistence of the cervical portion of the thymus and may occur anywhere along the course of the embryonic descent from the angle of the mandible to the sternal notch. Herein, we report two cases of dermal extrathyroidal CASTLE. The differential diagnosis of squamoid carcinoma with features of thymic differentiation includes extrathyroidal CASTLE, a primary squamous cell carcinoma with thymic differentiation, lymphoepithelioma-like carcinoma of the skin, and metastatic squamous cell carcinoma of unknown primary. It is essential that the latter two be ruled out before accepting the diagnosis of an extrathyroidal carcinoma with thymus-like differentiation.

Cytoplasmic localization of the oncogenic protein Ski in human cutaneous melanomas in vivo: functional implications for transforming growth factor beta signaling

The oncogenic protein Ski associates with Smad proteins and counteracts their activation of gene expression and growth inhibition in response to transforming growth factor beta (TGF-beta). Here we show that Ski protein levels are increased in all 44 human melanoma tumor tissues analyzed in vivo. In addition, Ski subcellular localization changes from nuclear, in preinvasive melanomas (melanomas in situ), to nuclear and cytoplasmic in primary invasive and metastatic melanomas. Furthermore, Ski/Smad association in the cytoplasm seems to prevent Smad3 nuclear translocation in response to TGF-beta. The biological significance of Ski overexpression in melanomas was established by showing that down-regulation of Ski levels, by antisense Ski vectors, restored TGF-beta-mediated growth inhibition. Such inhibition is apparently mediated by up-regulation of the cyclin-dependent kinase-I p21(Waf-1) and inhibition of cyclin-dependent kinase 2 activity. Our results suggest that high levels of Ski in human melanomas produce a disruption of TGF-beta signaling phenotypically similar to that in cells harboring mutations in TGF-beta receptors or Smad proteins, and this may represent a significant event in the progression of melanomas in vivo.

S100A6 preferentially labels type C nevus cells and nevic corpuscles: additional support for Schwannian differentiation of intradermal nevi

BACKGROUND

Melanocytic nevi typically show a morphologic sequence of maturation from epithelioid "type A" cells to fusiform, Schwann cell-like "type C" cells with dermal descent. Nevi may also produce Wagner-Meissner-like structures (nevic corpuscles). Previous studies have shown that this maturation of intradermal nevi recapitulates intermediate stages in Schwann cell development. In intradermal nevi, we have evaluated the pattern of S100A6 protein, a form of S100 found in Schwann cells.

METHODS

Formalin-fixed, paraffin-embedded archival tissues were evaluated by immunohistochemistry using antibodies specific for S100A6 and S100B in 38 intradermal nevi (IDN). Ten neurofibromas (NF), 3 Schwannomas (SCH), 2 palisaded and encapsulated neuromas (PEN), and 2 granular cell tumors (GCT) were included as positive controls since these lesions have large numbers of Schwann cells.

RESULTS

Melanocytic nevi demonstrated preferential anti-S100A6 staining of "type C" cells (36/38; 28 strong, 8 weak) and nevic corpuscles (25/38; 19 strong, 6 weak) compared to "type A" cells (17/38; 17 weak) and "type B" cells (17/38; 4 strong, 13 weak). All NF, SCH, and PEN stained strongly with anti-S100A6. Both GCT were negative with anti-S100A6 but positive with anti-S100B.

CONCLUSIONS

The pattern of S100A6 expression in intradermal nevi further supports the hypothesis that maturation in these lesions recapitulates features of Schwann cell differentiation. The lack of S100A6 expression by both GCT suggests that these lesions have lost this feature of Schwann cells, which may play a role in their peculiar phenotypic appearance.

Loss of expression of protein kinase C beta is a common phenomenon in human malignant melanoma: a result of transformation or differentiation?

As with most cancers, the aetiology of human cutaneous melanoma is likely to be multifactorial and to include the accumulation of irreversible alterations in an unknown number of genes. Elucidating this molecular progression necessitates both the identification of genetic perturbations at each clinically relevant stage, and the assessment of their impact on the normal melanocyte. The observation that the epidermal melanocyte, in contrast to metastatic melanoma cells, requires activation of the protein kinase C (PKC) pathway to facilitate growth in vitro indicates that one or more isoforms (or substrates) of this large and complex family of proteins are among those that undergo alteration during the development of malignant melanoma. Consequently, a number of studies have investigated the expression of various PKC family members in both melanocyte and melanoma cell lines, without a consensus of opinion as to which isoforms are of biological significance in melanoma development and progression. The present study involved a comprehensive evaluation of the PKC profile in normal melanocytes and in 16 metastatic melanoma cell lines. The results show that the major difference in isoform expression between epidermal melanocytes and melanoma cells is the loss of PKCbeta protein expression in 90% of melanoma cell lines. Examination of PKCbeta in benign and malignant melanocytic lesions revealed that this protein is either downregulated or absent in both naevi and metastatic melanomas. We conjecture that, although the loss of PKCbeta expression is a common phenomenon in malignant melanocytes, it may be related more to a normal process of melanocytic differentiation than to malignant transformation.

S100A6 expression in fibrohistiocytic lesions

BACKGROUND

S100A6, an S100 calcium-binding protein, has been found in a variety of cutaneous and extracutaneous lesions including: melanocytic nevi, melanoma, some salivary gland and epithelial tumors, and malignant fibrous histiocytoma (MFH). Dermal dendrocytes (DD) in the papillary dermis of skin also express S100A6 protein. We evaluated a variety of cutaneous fibrohistiocytic lesions to determine if the immunophenotype of S100A6 positivity can be expanded to include some or all of these lesions.

METHODS

Formalin-fixed, paraffin-embedded tissues from fibrous papules (FP, 20), dermatofibromas (DF, 20), dermatofibrosarcoma protuberans (DFSP, 5), atypical fibroxanthomas (AFX, 5), oral fibromas (3), digital fibroma (1), and dermatomyofibroma (1) were evaluated with antibodies to S100A6, S100B, factor XIIIa, and MAC387 using a one-hour capillary action-based immunohistochemical procedure.

RESULTS

DD in 20/20 FP, 19/20 DF, and 4/4 fibromas stained positively with anti-S100A6 in a pattern similar to anti-factor XIIIa. No DFSP cases stained with anti-S100A6. Anti-S100A6 showed superior staining to anti-factor XIIIa in 4/5 AFX cases.

CONCLUSIONS

The immunophenotypes of some fibrohistiocytic lesions can be expanded to include S100A6 protein. With the exception of AFX, the use of anti-S100A6 does not appear to offer added benefit over anti-factor XIIIa in the differential diagnosis of fibrohistiocytic lesions.

GM-CSF regulates protein and lipid catabolism by alveolar macrophages

Metabolism of surfactant protein (SP) A and dipalmitoylphosphatidylcholine (DPPC) was assessed in alveolar macrophages isolated from granulocyte-macrophage colony-stimulated factor (GM-CSF) gene-targeted [GM(-/-)] mice, wild-type mice, and GM(-/-) mice expressing GM-CSF under control of the SP-C promoter element (SP-C-GM). Although binding and uptake of (125)I-SP-A were significantly increased in alveolar macrophages from GM(-/-) compared with wild type or SP-C-GM mice, catabolism of (125)I-SP-A was markedly decreased in GM(-/-) mice. Association of [(3)H]DPPC with alveolar macrophages from GM(-/-), wild-type, and SP-C-GM mice was similar; however, catabolism of DPPC was markedly reduced in cells from GM(-/-) mice. Fluorescence-activated cell sorter analysis demonstrated decreased catabolism of rhodamine-labeled dipalmitoylphosphatidylethanolamine by alveolar macrophages from GM(-/-) mice. GM-CSF deficiency was associated with increased SP-A uptake by alveolar macrophages but with impaired surfactant lipid and SP-A degradation. These findings demonstrate the important role of GM-CSF in the regulation of alveolar macrophage lipid and SP-A catabolism.

Acantholytic dermatosis of the vulvocrural area

Acantholytic dermatosis of the vulvocrural area is a rare skin disorder characterized by solitary or multiple skin-colored to white, smooth papules or plaques. Histopathological features of both Hailey-Hailey disease and Darler's disease are present. There is acantholysis, which may involve the full thickness of the epidermis, and dyskeratosis with corps ronds and grains. There may be marked hyperkeratosis and focal parakeratosis. We report a case of this rare disease and discuss its differential diagnosis and treatment.

Update of diagnostic and prognostic markers in cutaneous malignant melanoma

The biomolecules described in this article generally have been studied as possible diagnostic or clinically prognostic markers in the context of melanoma disease progression as measured by the gold standards of tumor thickness and development of metastasis. Most of the markers showed variations in expression phenotype only during the deeply invasive or metastatic stage of tumor progression and were thus predictive of clinical outcome only for these subgroups of patients. Some of the markers may have utility in identifying patients with deeply invasive primary tumors who are likely to develop metastasis and thus should receive earlier, more aggressive treatments. In addition, some of the markers may identify patients likely to respond better to a new type of therapy (e.g., anti-angiogenic therapy in a patient whose tumor is overexpressing VEGF or immunotherapy for a patient whose tumor is expressing high levels of MART-1). In the future, it will probably be possible to employ new techniques, such as laser-guided microdissection of tissues, to isolate individual melanocytes in order to identify the earliest stage-specific defects that contribute to an aggressive biological behavior. Identifying the subset of patients with superficially invasive melanomas who will develop metastatic disease will continue to provide a challenge.

Distinct changes in pulmonary surfactant homeostasis in common beta-chain- and GM-CSF-deficient mice

Pulmonary alveolar proteinosis (PAP) is caused by inactivation of either granulocyte-macrophage colony-stimulating factor (GM-CSF) or GM receptor common beta-chain (beta(c)) genes in mice [GM(-/-), beta(c)(-/-)], demonstrating a critical role of GM-CSF signaling in surfactant homeostasis. To distinguish possible phenotypic differences in GM(-/-) and beta(c)(-/-) mice, surfactant metabolism was compared in beta(c)(-/-), GM(-/-), and wild-type mice. Although lung histology in beta(c)(-/-) and GM(-/-) mice was indistinguishable, distinct differences were observed in surfactant phospholipid and surfactant protein concentrations and clearance from lungs of beta(c)(-/-) and GM(-/-) mice. At 1-2 days of age, lung saturated phosphatidylcholine (Sat PC) pool sizes were higher in wild-type, beta(c)(-/-), and GM(-/-) mice compared with wild-type adult mice. In wild-type mice, Sat PC pool sizes decreased to adult levels by 7 days of age; however, Sat PC increased with advancing age in beta(c)(-/-) and GM(-/-) mice. Postnatal changes in Sat PC pool sizes were different in GM(-/-) compared with beta(c)(-/-) mice. After 7 days of age, the increased lung Sat PC pool sizes remained constant in beta(c)(-/-) mice but continued to increase in GM(-/-) mice, so that by 56 days of age, lung Sat PC pools were increased three- and sixfold, respectively, compared with wild-type controls. After intratracheal injection, the percent recovery of [(3)H]dipalmitoylphosphatidylcholine and (125)I-recombinant surfactant protein (SP) C was higher in beta(c)(-/-) compared with wild-type mice, reflecting decreased clearance in the receptor-deficient mice. The defect in clearance was significantly more severe in GM(-/-) than in beta(c)(-/-) mice. The ratio of SP Sat PC to SP-A, -B, and -C was similar in bronchoalveolar lavage fluid (BALF) from adult mice of all genotypes, but the ratio of SP-D to Sat PC was markedly increased in beta(c)(-/-) and GM(-/-) mice (10- and 5-fold, respectively) compared with wild-type mice. GM-CSF concentrations were increased in BALF but not in serum of beta(c)(-/-) mice, consistent with a pulmonary response to the lack of GM-CSF signaling. The observed differences in surfactant metabolism suggest the presence of alternative clearance mechanisms regulating surfactant homeostasis in beta(c)(-/-) and GM(-/-) mice and may provide a molecular basis for the range in severity of PAP symptoms. surfactant metabolism; alveolar macrophage; granulocyte-macrophage colony-stimulating factor

Expression of the intermediate filament peripherin in extraskeletal myxoid chondrosarcoma

The embryologic histogenesis of cartilage is not well characterized. While cranial cartilage is believed to be derived from pluripotential precursor cells of the neural crest, chondrocytes found elsewhere in the body are thought to be derived from mesoderm. As such, soft tissue tumors with cartilaginous differentiation may be related to neural crest or mesoderm. Peripherin is an intermediate filament encoded on chromosome 12, involved in growth and development of the peripheral nervous system. Peripherin is apparently expressed exclusively in cells derived from the neural crest and neural tube. A group of six soft tissue tumor types was selected because they are either of controversial differentiation or cytogenetically related to chromosome 12. A total of 41 cases was evaluated with antibodies against the intermediate filament peripherin. A panel of neural and neuroendocrine differentiation markers was used in selected cases. Three of five extraskeletal myxoid chondrosarcomas showed strong cytoplasmic reactivity with anti-peripherin. No peripherin expression was noted in any of eleven epithelioid sarcomas, eight liposarcomas, seven conventional chondrosarcomas, four neurothekeomas, three alveolar soft part sarcomas, or three clear cell sarcomas. The finding of peripherin expression in some extraskeletal myxoid chondrosarcomas may suggest the ability of some tumors to demonstrate both neural and chondroid differentiation.

Granulocyte-macrophage colony-stimulating factor in the innate immune response to Pneumocystis carinii pneumonia in mice

Innate immunity plays an important role in pulmonary host defense against Pneumocystis carinii, an important pathogen in individuals with impaired cell-mediated immunity. We investigated the role of GM-CSF in host defense in a model of P. carinii pneumonia induced by intratracheal inoculation of CD4-depleted mice. Lung GM-CSF levels increased progressively during the infection and were significantly greater than those in uninfected controls 3, 4, and 5 wk after inoculation. When GM-CSF gene-targeted mice (GM-/-) depleted of CD4+ cells were inoculated with P. carinii, the intensities of infection and inflammation were increased significantly compared with those in CD4-depleted wild-type mice. In contrast, transgenic expression of GM-CSF directed solely in the lungs of GM-/- mice (using the surfactant protein C promoter) dramatically decreased the intensity of infection and inflammation 4 wk after inoculation. The concentrations of surfactant proteins A and D were greater in both uninfected and infected GM-/- mice compared with those in wild-type controls, suggesting that this component of the innate response was preserved in the GM-/- mice. However, alveolar macrophages (AM) from GM-/- mice demonstrated impaired phagocytosis of purified murine P. carinii organisms in vitro compared with AM from wild-type mice. Similarly, AM production of TNF-alpha in response to P. carinii in vitro was totally absent in AM from GM-/- mice, while GM-CSF-replete mice produced abundant TNF in this setting. Thus, GM-CSF plays a critical role in the inflammatory response to P. carinii in the setting of impaired cell-mediated immunity through effects on AM activation.

IL-4 increases surfactant and regulates metabolism in vivo

Mice that express interleukin (IL)-4 in Clara cells (CCSP-IL-4) develop chronic airway inflammation and an alveolar proteinosis-like syndrome. To identify the role of IL-4 in surfactant homeostasis, we measured lipid and protein metabolism in the lungs of CCSP-IL-4 mice in vivo. Alveolar saturated phosphatidylcholine (Sat PC) pools were increased 6.5-fold and lung tissue Sat PC pools were increased 4. 8-fold in the IL-4 transgenic mice. Whereas surfactant protein (SP) A was increased proportionately to Sat PC, SP-D was increased approximately 90-fold in the IL-4 mice compared with wild-type mice and was associated with 2.8-fold increase in SP-D mRNA. The incorporation of palmitate and choline into Sat PC was increased about twofold in CCSP-IL-4 mice. Although trace doses of radiolabeled Sat PC were cleared from the air spaces and lungs of CCSP-IL-4 mice more slowly than in wild-type mice, net clearance of Sat PC from the lungs of CCSP-IL-4 mice was sixfold higher in the IL-4 mice than in wild-type mice because of the larger Sat PC pool sizes. Expression of IL-4 in Clara cells increased surfactant lipid synthesis and clearance, establishing a new equilibrium with increased surfactant pools and an alveolar proteinosis associated with a selective increase in SP-D protein, demonstrating a previously unexpected effect of IL-4 in pulmonary surfactant homeostasis.

Divergent cellular differentiation pathways during the invasive stage of cutaneous malignant melanoma progression

Melanocytic nevus cells in the dermis adopt many morphological features of Schwann cells. These differentiation-related changes typically are not observed in melanomas. However, nevus cells do not fully recapitulate a Schwann cell phenotype, because they lack expression of mature myelin-associated proteins. In this study, melanocytic nevi and malignant melanomas were examined by immunohistochemistry for expression of low-affinity nerve growth factor receptor (p75NGFR), neural cell adhesion molecule (CD56/N-CAM), and growth-associated phosphoprotein-43 (GAP-43). These three proteins define the earliest stages of Schwann cell development but are not expressed in myelinated Schwann cells or normal melanocytes. p75NGFR was expressed in 25 of 25 (100%) and CD56/N-CAM and GAP-43 in 23 of 25 (92%) nevi, predominantly in type C nevus cells and nevic corpuscles. Most (84%) of the nevi expressed all three proteins. In primary invasive and metastatic melanoma, expression of each of the three proteins was limited to </=20% of lesions but was not observed in any melanoma in situ (chi(2 )P < 0.0001). None of the melanomas expressed all three proteins (ANOVA P < 0.0001). These data confirm and extend earlier studies by showing that terminal differentiation of melanocytes in the dermis recapitulates some aspects observed in the earliest stages of Schwann cell development and that invasive melanomas follow a divergent pathway. Studying these early differentiation events may help to identify specific defects in the relevant signaling pathways and establish tenable targets for therapy of advanced-stage melanoma.

Desmoplastic (sclerotic) nevus: an underrecognized entity that resembles dermatofibroma and desmoplastic melanoma

Desmoplastic (sclerotic) nevus, a benign melanocytic neoplasm characterized by predominantly spindle-shaped nevus cells within a fibrotic stroma, can be confused with fibrous lesions and other melanocytic proliferations, including desmoplastic melanoma. We compared the histologic and immunohistochemical features of 16 desmoplastic nevi, nine desmoplastic melanomas, four hypopigmented blue nevi, and six dermatofibromas. The similarities between desmoplastic nevi and dermatofibromas included epidermal hyperplasia (12 of 16), presence of keloidal collagen (15 of 16), hypercellularity (16 of 16), and increased numbers of factor XIIIa-positive dendritic cells (12 of 12). The absence of adnexal induction (0 of 16), the rarity of lesions with multinucleated cells (3 of 16) or epidermal hyperpigmentation (2 of 16), and the presence of S-100 immunoreactivity (16 of 16) and melanocytic proliferation (9 of 16) helped differentiate desmoplastic nevi from dermatofibromas. The similarities between desmoplastic nevi and desmoplastic melanomas included the presence of atypical cells (16 of 16) and HMB-45 expression in the superficial portion of the lesions (11 of 16). The infrequent location on the head or neck (1 of 16), the absence of mitotic figures (0 of 16), a significantly lower number of Ki-67-reactive cells, and a decrease in HMB-45 expression in the deep area of the lesions (8 of 11) helped distinguish desmoplastic nevi from desmoplastic melanoma. Desmoplastic nevi had overlapping features with hypopigmented blue nevi, but features tending to favor the latter included a predominance of ovoid nuclei, higher numbers of atypical cells, and homogeneous staining with HMB-45. We conclude that a combination of histologic and immunohistochemical criteria facilitates the reliable diagnosis of desmoplastic nevus from its simulators.

Update of diagnostic and prognostic markers in cutaneous malignant melanoma

The biomolecules described in this article generally have been studied as possible diagnostic or clinically prognostic markers in the context of melanoma disease progression as measured by the gold standards of tumor thickness and development of metastasis. Most of the markers showed variations in expression phenotype only during the deeply invasive or metastatic stage of tumor progression and were thus predictive of clinical outcome only for these subgroups of patients. Some of the markers may have utility in identifying patients with deeply invasive primary tumors who are likely to develop metastasis and thus should receive earlier, more aggressive treatments. In addition, some of the markers may identify patients likely to respond better to a new type of therapy (e.g., anti-angiogenic therapy in a patient whose tumor is overexpressing VEGF or immunotherapy for a patient whose tumor is expressing high levels of MART-1). In the future, it will probably be possible to employ new techniques, such as laser-guided microdissection of tissues, to isolate individual melanocytes in order to identify the earliest stage-specific defects that contribute to an aggressive biological behavior. Identifying the subset of patients with superficially invasive melanomas who will develop metastatic disease will continue to provide a challenge.

Aerosolized GM-CSF ameliorates pulmonary alveolar proteinosis in GM-CSF-deficient mice

Surfactant proteins and phospholipids accumulate in the alveolar spaces and lung tissues of mice deficient in granulocyte-macrophage colony-stimulating factor (GM-CSF), with pathological findings resembling the histology seen in the human disease pulmonary alveolar proteinosis (PAP). Previous metabolic studies in GM-CSF-deficient [GM(-/-)] mice indicated that defects in surfactant clearance cause the surfactant accumulation in PAP. In the present study, GM(-/-) mice were treated daily or weekly with recombinant mouse GM-CSF by aerosol inhalation or intraperitoneal injection for 4-5 wk. Lung histology, alveolar macrophage differentiation, and surfactant protein B immunostaining returned toward normal levels in the GM-CSF aerosol-treated mice. Alveolar and lung tissue saturated phosphatidylcholine and surfactant protein B concentrations were significantly decreased after treatment with aerosolized GM-CSF. Cessation of aerosolized GM-CSF for 5 wk resulted in increased saturated phosphatidylcholine pool sizes that returned to pretreatment levels. In contrast, PAP did not improve in GM(-/-) mice treated daily for 5 wk with larger doses of systemic GM-CSF. Aerosolized GM-CSF improved PAP in the GM(-/-) mice, demonstrating that surfactant homeostasis can be influenced by local administration of GM-CSF to the respiratory tract.

GM-CSF-deficient mice are susceptible to pulmonary group B streptococcal infection

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-targeted mice (GM-/-) cleared group B streptococcus (GBS) from the lungs more slowly than wild-type mice. Expression of GM-CSF in the respiratory epithelium of GM-/- mice improved bacterial clearance to levels greater than that in wild-type GM+/+ mice. Acute aerosolization of GM-CSF to GM+/+ mice significantly enhanced clearance of GBS at 24 hours. GBS infection was associated with increased neutrophilic infiltration in lungs of GM-/- mice, while macrophage infiltrates predominated in wild-type mice, suggesting an abnormality in macrophage clearance of bacteria in the absence of GM-CSF. While phagocytosis of GBS was unaltered, production of superoxide radicals and hydrogen peroxide was markedly deficient in macrophages from GM-/- mice. Lipid peroxidation, assessed by measuring the isoprostane 8-iso-PGF2alpha, was decreased in the lungs of GM-/- mice. GM-CSF plays an important role in GBS clearance in vivo, mediated in part by its role in enhancing superoxide and hydrogen peroxide production and bacterial killing by alveolar macrophages.

Adenovirus-mediated granulocyte-macrophage colony-stimulating factor improves lung pathology of pulmonary alveolar proteinosis in granulocyte-macrophage colony-stimulating factor-deficient mice

Mutation of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene by homologous recombination causes progressive pulmonary alveolar proteinosis (PAP) in GM-CSF-deficient mice (GM-/-). The present study tested whether adenovirus-mediated expression of GM-CSF alters the progression of PAP in GM-/- mice. Adult mice were pretreated with an anti-T cell receptor (TCR) antibody to block T cell-mediated immune response, followed by intratracheal instillation of deltaE1-E3 replication-deficient adenovirus expressing mouse GM-CSF (Av1mGM). Mice were killed 1, 3, and 5 weeks after treatment to assess lungs for GM-CSF, surfactant protein B (SP-B), alveolar macrophage maturation, and type II cell proliferation. GM-CSF was detected in BAL fluid from GM-/- mice 1 week after Av1mGM treatment, and GM-CSF mRNA was detected by RT-PCR through 5 weeks. Five weeks after Av1mGM treatment, PAP was improved and SP-B decreased as assessed by ELISA and immunostaining. Increased numbers of alveolar macrophages stained with alpha-naphthyl acetate esterase (alpha-NAE) following treatment with Av1mGM. Local expression of GM-CSF with a recombinant adenovirus ameliorated PAP in the GM-/- mice in association with enhanced maturation of alveolar macrophages.

Granulocyte-macrophage colony-stimulating factor and pulmonary surfactant homeostasis

Pulmonary surfactant lining the alveolus of the lung is critical to postnatal adaptation to air breathing. Precise concentrations of surfactant proteins and lipids are maintained in the alveolar space by a careful balance among synthesis, recycling, and catabolism. Pulmonary alveolar proteinosis is a rare pulmonary disease associated with accumulation of surfactant lipids and proteins in the alveolar spaces. Recent work with transgenic mice demonstrated that disruption of the production of granulocyte-macrophage colony-stimulating factor (GM-CSF) or the common beta-subunit of the GM-CSF receptor caused alveolar proteinosis that was histologically similar to that seen in human patients. The defect in surfactant homeostasis is caused by decreased surfactant clearance, mediated (at least in part) by dysfunction of the alveolar macrophage. Local production of GM-CSF corrects the alveolar proteinosis in the GM-CSF knockout mouse. Likewise, transplantation of wild-type bone marrow cells expressing the common beta-chain of the GM-CSF receptor restores surfactant homeostasis in the GM-CSF receptor knockout mouse. These studies demonstrate the previously unanticipated role of GM-CSF signaling in surfactant homeostasis, mediated (at least in part) by its actions on the clearance of surfactant lipids and proteins by the alveolar macrophage. These findings may have important implications for the diagnosis and treatment of pulmonary alveolar proteinosis syndromes in humans.

Demonstration of Kaposi's sarcoma-associated herpes virus cyclin D homolog in cutaneous Kaposi's sarcoma by colorimetric in situ hybridization using a catalyzed signal amplification system

Kaposi's sarcoma-associated herpes virus (KSHV)/human herpes virus 8 (HHV8) DNA sequences have been demonstrated in Kaposi's sarcoma (KS), as well as in some acquired immunodeficiency syndrome (AIDS)-related non-Hodgkin's lymphomas (NHL) and in multicentric Castleman's disease. Although KSHV DNA generally is abundant in KSHV-associated lymphomas, few copies of the virus are present in KS, a property that confounds detection by in situ methods. Previous in situ studies, which identified KSHV in lesions of KS, relied on the use of polymerase chain reaction (PCR) to amplify target DNA sequences before in situ hybridization (ISH) for localization or used ISH with radioactively-labeled probes to obtain adequate levels of detection sensitivity. In this study, a novel nonisotopic nucleic acid ISH method using catalyzed signal amplification and colorimetric detection without PCR-dependent target amplification was used to identify KSHV-specific sequences. The level of sensitivity was increased further by using a probe that detects viral cyclin D homolog transcripts, which are expressed at significant levels during latent viral infection. Thirty cutaneous lesions of KS (25 AIDS-related and five classical European type) were evaluated. AIDS-related NHL and cell lines derived from patients with AIDS-related NHL, all of which were known to harbor KSHV by Southern blot analysis, were used as positive controls. NHL and benign cutaneous vascular lesions not associated with AIDS were used as negative controls. For each of the 30 KS lesions studied, hybridization signals were detected in most of the spindle cells surrounding the atypical slit-like vascular channels and also were detected in some endothelial cells in well-formed blood vessels in the perilesional dermis. Plaque and nodular lesions generally contained more labeled cells than did early patch lesions. All AIDS-related NHL and cell lines contained KSHV-specific sequences; however, the non-AIDS-related NHLs and benign vascular lesions were negative. These results confirm the presence of KSHV sequences in cutaneous KS and provide in situ evidence of infection by this virus in early patch-stage lesions. This study also defines the in situ expression of the KSHV cyclin D homolog viral oncogene in cutaneous KS. The use of this sensitive nonisotopic ISH method should allow detection of other KSHV-specific gene products, further defining the pathobiology of this virus.

Increased numbers of mast cells in human middle ear cholesteatomas: implications for treatment

HYPOTHESIS

Because many of the biologic phenomena in which mast cells are involved also are observed in human cholesteatoma pathology, the authors hypothesized that mast cells may play a role in this disease. The first test of this hypothesis is to determine whether there are an increased number of mast cells associated with cholesteatomas.

BACKGROUND

The molecular and cellular defects that result in the pathologic features observed in acquired and congenital cholesteatomas are unknown. One common feature of cholesteatoma pathogenesis is the presence of bacteria and a numerous inflammatory cytokines expressed by host inflammatory cells. The interactions between inflammatory cells and cholesteatoma epithelium could result in the induction of other aberrant biologic features of cholesteatomas. Thus, it is critical to the understanding of the pathogenesis of cholesteatomas to define the specific role of each cell type involved in this disease. Connective tissue mast cells have a complex retinue of functions mediated via the secretion of a variety of cytokines and proteinases, and many of the biologic phenomena in which mast cells are involved also are observed in cholesteatoma pathology.

METHODS

The authors evaluated by immunohistochemistry 36 cholesteatomas of all types (e.g., primary and secondary acquired, recurrent, and congenital) and 23 specimens of normal tissues (e.g., tympanic membrane, canal wall skin, and postauricular skin) for the expression of tryptase, a mast cell-specific protease.

RESULTS

Cholesteatomas showed approximately threefold to sevenfold increase in the concentration of mast cells when compared with that of normal tissues. In addition, 19-34% of the mast cells were found within the suprabasal layers of the squamous epithelium of cholesteatoma subgroups, a phenomenon observed only in grossly inflamed tympanic membrane specimens, but not in other control tissues including minimally inflamed tympanic membranes.

CONCLUSIONS

The authors conclude from these data that mast cells may represent a previously unrecognized host inflammatory cell, which plays an important role in the development of one or more traits of cholesteatoma pathology.

A comparison of sonographic examinations for trauma performed by surgeons and radiologists

BACKGROUND

It has been demonstrated that surgeons and surgery residents, trained in the focused abdominal sonographic examination, are able to accurately and reliably evaluate trauma patients. Despite this, radiologists have objected to surgeon-performed sonography for several reasons. We set out to compare the accuracy of sonographic examinations performed by surgery residents and radiologists.

METHODS

A retrospective review of medical records of all trauma patients who received focused ultrasound examinations from January 1, 1995, through June 30, 1996, at one of two American College of Surgeons-verified Level I trauma centers in the same city was undertaken. Ultrasound examinations were performed by surgery residents at trauma center A (TCA) and by radiologists or radiology residents at trauma center B (TCB). Findings for each patient were compared with the results of computed tomography, diagnostic peritoneal lavage, operative exploration, or observation. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated for each group of patients. Comparison of patient charges for the trauma ultrasound examinations at each of the trauma centers was also made.

RESULTS

Patient populations at the two centers were similar except that the mean Injury Severity Score at TCB was higher than at TCA (11.74 vs. 9.6). Sensitivity, specificity, accuracy, or negative predictive value were not significantly different between the two cohorts. A significantly lower positive predictive value for examinations performed by surgery residents was noted and attributed to a lower threshold of the surgery residents to confirm their findings by computed tomography. Billing data revealed that the average charge for trauma sonography by radiologists (TCB) was $406.30. At TCA, trauma sonography did not generate a specific charge; however, a $20.00 sum was added to the trauma activation fee to cover ultrasound machine maintenance and supplies.

CONCLUSION

Focused ultrasound examination in the trauma suite can be as safely and accurately performed by surgery residents as by radiologists and radiology residents and should be a routine part of the initial trauma evaluation process.

Neosporosis-associated bovine abortion in Pennsylvania

Neospora caninum was found in fetal tissues of 34 of 688 cases of bovine abortion submitted to the Pennsylvania Animal Diagnostic Laboratory System during the period from May 1994 to November 1996. The aborted fetuses ranged in gestational age from 3 to 8 months. Microscopic lesions consisted primarily of encephalitis and myocarditis. A labeled (strept) avidin-biotin staining procedure using anti-N. caninum polyclonal rabbit serum revealed N. caninum organisms within the fetal brain (27 of 27), heart (10 of 13), placenta (5 of 6), kidney (2 of 2), liver (1 of 4) and skeletal muscle (1 of 1).

Expression of p53 protein in human middle ear cholesteatomas: pathogenetic implications

BACKGROUND

Cholesteatoma is a destructive lesion of the middle ear or mastoid process or both. The molecular and cellular defects that result in the clinical hallmarks of acquired and congenital cholesteatomas, namely invasion, migration, uncoordinated proliferation, altered differentiation, aggressiveness, and recidivism, are unknown. Determining the existence of defects in the normal biology, biochemistry, and genetic complement of the major cellular constituents comprising a cholesteatoma (i.e., fibroblasts and keratinocytes) is critical to the understanding of the pathogenesis of cholesteatomas. It has been speculated that the development of human cholesteatomas is due, in part, to the altered control of cellular proliferation, which tilts the balance toward the aggressive, invasive growth of squamous epithelium within the middle ear. However, whether this altered control is due to defects in the mechanisms and underlying genes that control proliferation, or to cytokines released from infiltrating inflammatory cells, or to some other mechanism is unknown. The nuclear phosphoprotein p53 tumor suppressor gene plays a critical regulatory role in cell cycle control and apoptosis. In the current article, the authors have analyzed congenital, primary and secondary acquired, and recurrent cholesteatomas for the altered expression of p53 and Ki-67, a marker of active proliferation.

METHODS

p53 and Ki-67 expression was determined by immunohistochemical assays using specific monoclonal antibodies.

RESULTS

The authors' results indicate that p53 is elevated 9- to 20-fold in all cholesteatomas when compared to the expression of p53 in normal postauricular skin or tympanic membrane. However, there is no concomitant increase in Ki-67 expression in cholesteatomas.

CONCLUSIONS

These data indicate a defect in cholesteatomas in the mechanisms that p53 engages (i.e., cell cycle control or apoptosis or both). In addition, these data further suggest that there is no intrinsic difference between any clinicopathologic group of cholesteatomas, at least with respect to p53-expression and, presumably, p53 function.

The neuropeptide/mast cell secretagogue substance P is expressed in cutaneous melanocytic lesions

Substance P (SP) is a neuropeptide found in both the central and peripheral nervous system. In the skin, SP-containing neurons stimulate the release of histamine from connective tissue mast cells (MC). SP also can potentiate neoangiogenesis and induce dermal fibrosis. MC-derived histamine has potent vasoactive effects, is angiogenic, and promotes tissue fibroplasia. In addition to histamine, MC contain many other angiogenic factors and a variety of cytokines, growth factors, and proteolytic enzymes implicated in tissue remodeling, and normal as well as tumor-associated neoangiogenesis. Many MC-derived factors, including histamine, can enhance melanoma cell growth directly. MC often concentrate around cutaneous melanomas which also frequently are associated with angiogenesis and peritumoral fibrosis. The precise mediators of these responses have not been well defined. We evaluated by immunohistochemistry cutaneous lesions representing stages of progression of malignant melanoma and its precursor lesions for the expression of SP. SP was expressed in 17/25 (68%) primary invasive malignant melanomas, 2/5 (40%) metastatic melanomas, 6/10 (60%) melanomas in situ, 7/12 (58%) atypical (dysplastic) nevi, and 4/10 (40%) spindle and epithelioid cell (Spitz) nevi, but was not detected in any (0/11, 0%) acquired benign melanocytic nevi (p<0.05). Invasive melanomas were immunolabeled in both the intraepidermal and the dermal components of the lesions. For those atypical and Spitz nevi which expressed SP, most of the immunoreactive melanocytes were located at the dermal-epidermal junction overlying areas of papillary dermal fibrosis. The results show differential expression of SP among cutaneous melanocytic lesions and suggest that the expression of this neuropeptide together with other factors may contribute to some of the host responses associated with these lesions.

Differential expression of the intermediate filament peripherin in cutaneous neural lesions and neurotized melanocytic nevi

Peripherin is an intermediate filament involved in growth and development of the peripheral nervous system, and is produced by neurons and the beta cells of the islets of Langerhans. Recently, malignant melanomas and some melanocytic nevi have been shown to express peripherin. It is unknown if Schwann cells, also derived from the neural crest, express peripherin. Expression of peripherin was evaluated by immunohistochemistry in cutaneous lesions characterized by a prominent Schwann cell component including 26 neurofibromas (NF), 10 schwannomas (SCH), seven granular cell tumors, and five palisaded encapsulated neuromas (PEN); 13 neurotized melanocytic nevi (NMN) also were evaluated because these lesions contain Wagner-Meissnerlike structures and type C nevus cells, which exhibit a "schwannian" phenotype. Peripherin was detected in the axons of normal peripheral nerves. NF and PEN contained numerous axons dispersed throughout the lesions, whereas only scattered small nerves were seen in GCT. In SCH, only rare axons were labeled, mostly at the periphery of the lesions. All other cells in these four types of lesions, therefore including Schwann cells, were not labeled. In most NMN, labeled axons were identified within the lesions. In a few cases, rare epithelioid melanocytes within the superficial portions of the nevi were labeled. The Wagner-Meissnerlike structures and type C nevus cells (schwannian) were not labeled in any lesion; however, numerous labeled axons invested these areas. Because there are different relative numbers of peripherin-labeled axons throughout NF, PEN, some nevi, and SCH, analysis of peripherin expression may be helpful in the diagnosis of these lesions. Neurons and some epithelioid melanocytes, in contrast to type C nevus cells and Schwann cells of NF and SCH, express peripherin, providing further evidence for a transition from a more neuronal to a more schwannian phenotype during the normal maturation sequence of melanocytes in nevi.