Influence of rib impact on thoracic gunshot trauma.

INTRODUCTION: The influence of rib impact on thoracic gunshot trauma remains unclear, despite its high occurrence. This study therefore investigates the effect of rib impact on a bullet's terminal properties and injury severity. METHODS: Two bullets were used: 5.56×45 mm (full charge and reduced charge) and 7.62×51 mm (full charge). For each bullet, three impact groups were tested: (1) plain 10% ballistic gelatin (control) conditioned at 4°C, (2) intercostal impact, and (3) rib impact, the latter two tested with samples of porcine thoracic walls embedded in gelatin. Analysis included penetration depth, trajectory change, yaw, fragmentation, velocity reduction, energy deposition and temporary and permanent cavity characteristics. RESULTS: No significant differences were observed for most variables. Differences were found between rib (and intercostal) impact and the control groups, suggesting that the inclusion of thoracic walls produces an effect more significant than the anatomical impact site. Effects were ammunition specific. For the 7.62×51 mm round, rib impact caused an earlier onset of yaw and more superficial permanent gelatin damage compared with plain gelatin. This round also formed a larger temporary cavity on rib impact than intercostal impact. Rib (and intercostal impact) created a smaller temporary cavity than the control for the 5.56×45 mm round. For the reduced-charge 5.56×45 mm round, rib and intercostal impact produced greater velocity reduction compared with plain gelatin. CONCLUSIONS: This study provides new insights into the role of rib impact in thoracic gunshot injuries, and indicates that the effects are ammunition dependent. Unlike the 5.56×45 mm rounds, rib impact with the 7.62×51 mm rounds increases the risk of severe wounding.

Adaptation of the adult Functional Mobility Assessment (FMA) into a FMA-Family Centred (FMA-FC) paediatric version.

AIM: The aims of this study were to adapt an adult wheeled mobility outcome measure, the Functional Mobility Assessment, for use with children (FMA-Family Centred) and establish the new measure's content validity, test-retest reliability, and internal consistency. BACKGROUND: Although several tools exist to measure a child's ability to operate and move a wheeled mobility device, none focus on the ability of the wheeled mobility device to support children and their families as they perform daily activities. METHODS: After adapting the FMA items with examples relevant to children aged 3-21, parent/caregiver and therapist stakeholder groups recommended adaptations relevant for families with children who cannot respond for themselves. RESULTS: Six of the initial FMA items were retained with child-appropriate examples, and 4 new items were developed. CONCLUSION: The content validity of the FMA-Family Centred was strongly supported, and internal consistency and test-retest reliability met accepted psychometric standards.

A randomised trial of skin photography as an aid to screening skin lesions in older males.

OBJECTIVES: We have previously shown that photographs assist in detection of change in skin lesions and designed the present randomised population based trial to assess the feasibility of photographs as an aid to management of skin cancers in older men. SETTING: 1899 men over fifty, identified from the electoral roll in two regions in New South Wales (NSW), Australia, were invited by mail to participate. METHODS: A total of 973 of 1037 respondents were photographed and randomised into intervention (participants given their photographs) or control groups (photographs withheld by investigators). At one and two years from the time of photography, all participants were advised to see their primary care practitioner for a skin examination. Those in the intervention group were examined with their photographs and those in the control group without their photographs. RESULTS: The results indicated that the practitioners were more likely to leave suspicious lesions in place for follow up observation (37% v 29%) (p=0.006) and less likely to excise benign non pigmented lesions (20 v 32%). There was little difference in excision rates for benign pigmented lesions (21% v 23%). Lesions excised were more likely to be non-melanoma skin cancer (58% v 42%) from patients who had photographs compared to those without photographs (p=0.005). The use of skin photography resulted in a substantial savings due to the reduced excision of benign lesions. CONCLUSIONS: These results suggest that it would be feasible to conduct a large scale randomised trial to evaluate the value of photography in early detection of melanoma and that such a trial could be cost effective due to the reduced excision of benign skin lesions.

Immune complex formation after xenotransplantation : evidence of type III as well as type II immune reactions provide clues to pathophysiology.

Rejection of renal and cardiac xenografts is initiated when natural antibodies of the recipient bind to donor endothelium, activating complement on the surface of endothelial cells. Pulmonary xenotransplants, however, reveal less evidence of antibody binding and complement activation and, in contrast to other xenografts, fare worse when the complement of the graft recipient is depleted. Accordingly, we asked whether distinct immunochemical reactions might occur after xenotransplantation of the lung and what implications such reactions might have for pulmonary pathophysiology. Analysis of serum from baboons after transplantation with porcine lungs revealed complexes containing baboon IgM and porcine von Willebrand factor. The baboon IgM in these complexes was specific for Galalpha1-3Gal. Immune complexes were also seen, albeit to a lesser extent, in the serum of kidney and heart xenotransplant recipients. Deposits of porcine von Willebrand factor and baboon C3 were detected in livers and spleens of transplanted baboons. These results indicate pulmonary xenotransplantation eventuates in formation of immune complexes and in the deposition of those complexes at distant sites. Immune complex formation could explain the peculiar fate of xenoreactive antibodies after pulmonary xenotransplantation and might contribute to the pathophysiology of the lung and systemic changes not previously considered a complication of xenotransplantation.

Analysis of a bone assemblage made by chimpanzees at Gombe National Park, Tanzania.

Chimpanzee hunting provides information on prey characteristics and constraints acting on a large-bodied primate lacking a hunting technology, and has important implications for modeling hunting by fossil hominids. Analysis of the remains of five red colobus monkeys captured and consumed by Gombe chimpanzees in a single hunting bout provides one of the first opportunities to investigate the characteristics of prey bones surviving chimpanzee consumption. Four of the five individuals (an older infant, two juveniles and one subadult) were preserved in the bone assemblage; a neonate was entirely consumed. Cranial and mandibular fragments had the highest survivorships, followed by the scapulae and long bones. Post-cranial axial elements had the lowest survivorships. A high percentage (80%) of the long bones and ribs surviving consumption were damaged, most commonly through crenulation and step fracturing of bone ends. One of two partially reconstructed crania preserves a canine puncture through its left parietal. Proposed characteristics of faunal assemblages formed through chimpanzee-like hunting include small modal prey size, limited taxonomic diversity, a high proportion of immature individuals and a high frequency of skull bones. These characteristics would not uniquely identify hunting by fossil primates in the geological record, necessitating a contextual approach to diagnose hunting by hominids not forming an archeological record. Hominid utilization of vertebrate tissue is first unambiguously documented at 2.5 m.y.a. Rather than representing a strict "scavenging phase" in the evolution of hominid-prey interactions, Oldowan hominid carnivory may represent the overlay of large mammal scavenging on a tradition of small mammal hunting having a low archeological visibility.

Structural basis for the substrate specificity of endo-beta-N-acetylglucosaminidase F(3).

Endo-beta-N-acetylglucosaminidase F(3) cleaves the beta(1-4) link between the core GlcNAc's of asparagine-linked oligosaccharides, with specificity for biantennary and triantennary complex glycans. The crystal structures of Endo F(3) and the complex with its reaction product, the biantennary octasaccharide, Gal-beta(1-4)-GlcNAc-beta(1-2)-Man-alpha(1-3)[Gal-beta(1-4)-GlcNAc-be ta(1-2)-Man-alpha(1-6)]-Man-beta(1-4)-GlcNAc, have been determined to 1.8 and 2.1 A resolution, respectively. Comparison of the structure of Endo F(3) with that of Endo F(1), which is specific for high-mannose oligosaccharides, reveals highly distinct folds and amino acid compositions at the oligosaccharide recognition sites. Binding of the oligosaccharide to the protein does not affect the protein conformation. The conformation of the oligosaccharide is similar to that seen for other biantennary oligosaccharides, with the exception of two links: the Gal-beta(1-4)-GlcNAc link of the alpha(1-3) branch and the GlcNAc-beta(1-2)-Man link of the alpha(1-6) branch. Especially the latter link is highly distorted and energetically unfavorable. Only the reducing-end GlcNAc and two Man's of the trimannose core are in direct contact with the protein. This is in contrast with biochemical data for Endo F(1) that shows that activity depends on the presence and identity of sugar residues beyond the trimannose core. The substrate specificity of Endo F(3) is based on steric exclusion of incompatible oligosaccharides rather than on protein-carbohydrate interactions that are unique to complexes with biantennary or triantennary complex glycans.

Heparanase expression in invasive trophoblasts and acute vascular damage.

Heparan sulfate proteoglycans play a pivotal role in tissue function, development, inflammation, and immunity. We have identified a novel cDNA encoding human heparanase, an enzyme thought to cleave heparan sulfate in physiology and disease, and have located the HEP gene on human chromosome 4q21. Monoclonal antibodies against human heparanase located the enzyme along invasive extravillous trophoblasts of human placenta and along endothelial cells in organ xenografts targeted by hyperacute rejection, both sites of heparan sulfate digestion. Heparanase deposition was evident in arterial walls in normal tissues; however, vascular heparan sulfate cleavage was coincident with heparanase enzyme during inflammatory episodes. These findings suggest that heparanase elaboration and control of catalytic activity may contribute to the development and pathogenesis of vascular disease and suggest that heparanase intervention might be a useful therapeutic target.

Expression of tissue factor mRNA in cardiac xenografts: clues to the pathogenesis of acute vascular rejection.

BACKGROUND: Acute vascular rejection destroys vascularized xenografts over a period of hours to days and is now considered the major hurdle to the clinical application of xenotransplantation. The hallmark of acute vascular rejection is diffuse intravascular coagulation; however, the pathogenesis of coagulation is a matter of controversy. One line of evidence points to activated endothelial cells and another to activated inflammatory cells as a source of tissue factor and thus as a primary cause of this lesion. The distinction between the two mechanisms inducing coagulation in the xenograft provides an opportunity for specific intervention. METHODS: To explore these mechanisms, we studied the expression of tissue factor mRNA by in situ reverse transcriptase-polymerase chain reaction in relation to the histopathologic manifestations of acute vascular rejection in guinea pig hearts transplanted into rats treated by cobra venom factor to avoid the hyperacute rejection. RESULTS: Three hours after transplantation and before the deposition of fibrin, tissue factor mRNA was expressed in the endothelial cells lining small and medium blood vessels and in smooth muscle cells of guinea pig cardiac xenografts. Sixteen hours after transplantation, while rat tissue factor mRNA was expressed only in occasional infiltrating cells, cardiac xenografts showed prominent deposits of fibrin in small vessels. Maximum expression of tissue factor on rat infiltrating cells was observed 48 hr after transplantation. CONCLUSIONS: These results suggest that in acute vascular rejection, coagulation is initiated on the donor vascular system, while the procoagulant characteristics of infiltrating cells may reflect a response to tissue injury rather than a cause.

Auditory responses in the vocal motor system of budgerigars.

Budgerigars (Melopsittacus undulatus) are small Australian parrots that can imitate novel sounds in adulthood and therefore serve as a convenient model system for the study of vocal learning in adult animals. Previous anatomical studies had indicated that known auditory regions in the telencephalon of budgerigars are connected, albeit indirectly and rather sparsely, to vocal motor nuclei. Physiological evidence for connections between the auditory and vocal motor systems in budgerigars had been lacking, however. Here, we show that neurons in a telencephalic vocal motor region, i.e., the central nucleus of the lateral neostriatum (NLc), are responsive to auditory stimuli in isoflurane-anesthetized budgerigars. These responses are highly variable from trial to trial and frequently have latencies in excess of 100 ms. Neurons in NLc generally respond better to a budgerigar's own contact call than to a white noise stimulus, but the response preferences of NLc neurons in budgerigars are generally weaker and more diverse than the response preferences of neurons in the high vocal center of songbirds, which is probably analogous to NLc. These data indicate that parrots and songbirds, which have evolved the ability to learn vocalizations independently of one another, have both evolved physiologically effective connections between their auditory and vocal motor systems. Interestingly, however, the anatomical pathways by which the auditory and vocal motor systems interact, and the physiological details of how they communicate, appear to be significantly different between the two taxa.

Participation of older males in a study on photography as an aid to early detection of melanoma.

OBJECTIVE: To examine the acceptability of photography as an aid to skin examinations in men over 50 years of age. METHODS: A randomised trial of men selected from the electoral roll. All participants were photographed, but only half received their photographs. Skin examinations by GPs at years one and two. RESULTS: 55% of men consented to have photographs taken and 51% did so. 86% of respondents had risk factors for melanoma (compared to 68% of non-responders) and 47% had two or more risk factors (compared to 23% of non-responders). At year one, 91% of participants remaining in study regions had been examined. Photographs were lost by only six participants. CONCLUSIONS: Men over 50 years of age respond to personalised health messages about melanoma and respondents include a high proportion of males with risk factors for melanoma. IMPLICATIONS: These initial results suggest that photography may be a logistically acceptable approach for assisting in the early detection of melanoma.

Current research on the late Pliocene and Pleistocene deposits north of Homa Mountain, southwestern Kenya.

The late Pliocene and Pleistocene sediments of the Homa Peninsula in southwestern Kenya are richly fossiliferous, preserve Early Stone Age archaeological traces and provide one of the few paleoanthropological data sets for the region between the branches of the East African Rift Valley. This paper presents preliminary results of our ongoing investigation of late Pliocene and Pleistocene deposits at the localities of Rawi, Kanam East, Kanam Central and Kanjera. While fossils have been collected from the peninsula since 1911, little systematic effort has been made to place them into a broader litho-and chronostratigraphic framework. This project has conclusively demonstrated that fossils occur in good stratigraphic context at all of the study localities and that claims of sediment slumping (Boswell, 1935) have been greatly overstated (Behrensmeyer et al., 1995; Plummer & Potts, 1989). A provisional chronostratigraphic framework based on magneto- and biostratigraphy is presented here. We have revised the Plio-Pleistocene stratigraphy of the Rawi and Kanam gullies to include three formations: the Rawi, Abundu and Kasibos Formations. Based on magneto- and biostratigraphy, these formations are dated between approximately three and one m.y.a. (Gauss Chron-Jaramillo Subchron) (Cande & Kent, 1995). The Apoko Formation unconformably overlies the others and may be middle to late Pleistocene in age. All formations contain rich patches of fossils, and Acheulean artifacts have been surface collected from the Abundu and Kasibos Formations. Deposition of the fossil- and artefact-bearing sediments at Kanjera North began in the early Pleistocene and continued into the middle Pleistocene. Deposition at Kanjera South began over one million years earlier than previously thought, at approximately 2.2 m.y.a., and continued into the Olduvai Subchron (1.770-1.950 m.y.a.; Cande & Kent, 1995). Excavations have recovered Oldowan artefacts in association with well-preserved fossil fauna near the base of the sequence, the oldest archaeological traces yet known from southwestern Kenya.

Research on late Pliocene Oldowan sites at Kanjera South, Kenya.

The late Pliocene is notable for the appearance of two new hominid genera as well as the first archaeological sites, generally attributed to the Oldowan Industrial Complex. However, the behavioral ecology of Oldowan hominids has been little explored, particularly at sites older than 2.0 Ma. Moreover, debates on Oldowan hominid foraging ecology and behavior have centered on data from only two regions, and often from single site levels. Here we describe the preliminary results of our investigation of Oldowan occurrences at Kanjera South. These occurrences preserve the oldest known traces of hominid activity in southwestern Kenya, and unlike most of the Oldowan sites in the 2.0-2.5 Ma time interval, artefacts are found in spatial association with a well-preserved fauna. In 1996 and 1997, this project initiated the first excavation program for Kanjera South. Magneto- and biostratigraphy indicate that deposition began approximately 2.2 Ma, substantially earlier than previously thought. At Excavation 1, artefacts were found in spatial association with a taxonomically diverse faunal assemblage in Beds KS-1 and KS-2. Excavation 2 yielded a partial hippopotamus axial skeleton with artefacts in KS-3. Cores from both sites were incidentally flaked and represent a Mode I lithic technology indistinguishable from the Oldowan. Approximately 15% of the artefacts were manufactured from non-local raw materials, indicating a flow of resources into the area. Stable isotopic analysis of KS-1 and KS-2 pedogenic carbonates suggests that the Excavation 1 assemblages formed in a relatively open (>75% C4 grass) habitat. The Excavation 1 and 2 faunas contain a high proportion of equids relative to Oldowan accumulations from Bed I Olduvai Gorge, Tanzania. Beds KS-1 and KS-2 thus preserve traces of Oldowan hominid activities in a more open setting than has been previously documented.

In situ hybridization detection of low copy nucleic acid sequences using catalyzed reporter deposition and its usefulness in clinical human papillomavirus typing.

In situ hybridization (ISH) detection of low copy DNA and RNA sequences using nonisotopic probes has been difficult in the past because of a lack of sensitivity. Several techniques, such as ISH with radioisotopic-labeled probes, in situ polymerase chain reaction, in situ reverse transcription polymerase chain reaction, self-sustained sequence replication, and chemiluminescence, have allowed increased sensitivity but have required specialized and often expensive equipment, lengthy protocols, and in the case of radioactive probes, there has been an associated increased health risk. Catalyzed reporter deposition (CARD) combined with ISH (CARD-ISH) increases the signal-generating potential of labeled hybridized probes and allows the detection of low copy sequences of nucleic acids in formalin-fixed, paraffin-embedded tissue sections. To determine the sensitivity of CARD-ISH to detect nucleic acids in routinely processed specimens, we analyzed the detection of HPV 16 and 18 infection in formalin-fixed, paraffin-embedded sections of cultured cell lines, including CaSki cells with 400-600 copies of HPV 16, HeLa 229 cells with 10-50 copies of HPV 18, and SiHa cells with 1-2 copies of HPV 16 using a conventional ISH method and by CARD-ISH. In addition, 20 cases of clinical specimens previously analyzed for HPV 6, 11, 16, 18, 31, 33, and 51 with the Enzo PathoGene kit (Enzo Diagnostics, Inc., Farmingdale, NY, U.S.A.) were reexamined with the CARD-ISH method. The CARD-ISH system detected one to two copies of HPV 16 in the SiHa cells whereas the conventional ISH method did not. Both methods detected HPV 16 and 18 in CaSki and HeLa 229 cells, respectively. Three clinical cases that were previously negative and two weakly positive cases of HPV infection were all strongly positive with the CARD-ISH system, a 25% increase in the detection of positive cases by CARD-ISH. We also showed for the first time that a cocktail of six biotinylated oligonucleotide probes was capable of detecting one to two copies of HPV 16 in SiHa cells. These results show that the CARD-ISH method increases the sensitivity of nonisotopic ISH to the level of detecting one to two copies of HPV DNA in formalin-fixed, paraffin-embedded tissue sections using biotinylated cDNA or oligonucleotide probes.

Overexpression of PNGase at from baculovirus-infected insect cells.

Peptide-N4-(N-acetyl-beta-d-glucosaminyl asparagine amidase) from Aspergillus tubigensis (PNGase At) was expressed in baculovirus-infected insect cells. The recombinant PNGase At was secreted and purified to homogeneity with a yield of 9.5 mg per liter of infected cell medium. Recombinant PNGase At migrated upon SDS-PAGE as a single-chain protein with a molecular mass of 78 kDa. This contrasts with the native Aspergillus enzyme which is "nicked" and migrates as two subunits each with a molecular weight about 43 kDa. Quantitation of total sugar by phenol-sulfuric acid suggests that the enzyme expressed in baculovirus-infected insect cells was substituted with 8-10 chains of carbohydrate of which 75% was released by Endoglycosidase F1. ESI-MS analysis of the oligosaccharides released from the recombinant PNGase At revealed similarity in the number of glycosylated residues but a significant difference in their composition, when compared to the carbohydrates of the native PNGase At. Despite differences in the primary structure and in the composition of glycan residues, the recombinant enzyme had the same specific activity as the native enzyme.