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The study was aimed to investigate the pathological changes of condemned lungs of dromedary camels in the Sudan abattoirs using conventional H & E and Zeihl Neelson (ZN) staining procedures. Proliferative granulomatous reaction was demonstrated in one H & E stained lung section which was characterized by focal fibrosis and infiltration of mononuclear cells resembled to tuberculous lesions. While ZN stained sections demonstrated acid fast rod in one pulmonary associated lymph node. These lesions were evidenced presence of tuberculous mycobacteria in camel tissues and recommended further deep investigation of tuberculosis among camels in the Sudan.

Allogenic bone graft has been considered the gold standard in connection with bone graft material in revision joint arthroplasty. However, the lack of osteogenic potential and the risk of disease transmission are clinical challenges. The use of osteoinductive materials, such as demineralized bone matrix (DBM), alone or in combination with allograft or commercially available human cancellous bone (CB), may replace allografts, as they have the capability of inducing new bone and improving implant fixation through enhancing bone ongrowth. The purpose of this study was to investigate the effect of DBM alone, DBM with CB, or allograft on the fixation of porous-coated titanium implants. DBM100 and CB produced from human tissue were included. Both materials are commercially available. DBM granules are placed in pure DBM and do not contain any other carrier. Titanium alloy implants, 10 mm long × 10 mm diameter, were inserted bilaterally into the femoral condyles of eight skeletally mature sheep. Thus, four implants with a concentric gap of 2 mm were implanted in each sheep. The gap was filled with: (a) DBM; (b) DBM:CB at a ratio of 1:3; (c) DBM:allograft at a ratio of 1:3; or (d) allograft (gold standard), respectively. A standardized surgical procedure was used. At sacrifice 6 weeks after implantation, both distal femurs were harvested. The implant fixation was evaluated by mechanical push-out testing to test shear mechanical properties between implant and the host bone and by histomorphometry. Non-parametric tests were applied; p

Systematics of R. darlingi Eastern R. darlingi, which includes the holotype of R. d. barbetonensis (TM 2476), are genetically distinct from western R. darlingi, the two groups occurring in different clades. Eastern R. darlingi is embedded in the fumigatus clade that includes R. fumigatus, R. eloquens and R. hildebrandtii. Western R. darlingi form a monophyletic clade which diverged from the fumigatus clade ~9.7 Mya (Figure 2). Furthermore, the percentage sequence divergence for cyt b within eastern R. darlingi (1.3%) and within western R. darlingi (2.1%) was much lower than between the two clades (8.1%). This percentage sequence divergence falls within the range used to distinguish other species of bats (3–27%; [20, 45]). This divergence was supported by differences in the size and shape of the bacula, characteristics which may act as crucial pre-zygotic reproductive barriers [60]. Ecological niche modelling showed substantial differences in the ecology of the two lineages. The distribution of the western lineage (damarensis; Figure 5) is restricted to the drier, hotter western half of the subcontinent (Figures 5b and 6b) characterisedbyanannualprecipitationof R. darlingi; Figure 5a) is restricted to the more mesic eastern half of the subcontinent (Figures 5a and 6a) suggesting a limited tolerance to arid conditions and a general absence from regions with an annual precipitationof 55% (Figure 6a). Thus, there are species level genetic differences supported by differences in bacula morphology as well as substantial ecological differences between R. darlingi in the east and R. darlingi in the west, suggesting that a taxonomic revision is required despite their substantial convergence in echolocation frequency and skull and post-cranial morphology. Since the type specimen of R. darlingi was collected in Zimbabwe (eastern part of the subcontinent) we retain the name R. darlingi for the eastern lineage (Figure 1). Henceforth we refer to individuals in the western lineage as R. damarensis because the holotype of R. d. damarensis (TM9474, locality Namibia; Table S2 and Appendix S 1 in File S1 Supporting Information) is associated with this group (Figure 3). The distribution of R. darlingi is restricted to the mesic eastern parts of the subcontinent (Figure 5a) and is described in detail in Monadjem et al. [42]. It appears to occupy mainly woodland and grassland biomes (Figure 5a; [41, 42]). The distribution of R. damarensis is restricted to the xeric regions from south-western Angola, through northern Namibia, southwards as far as Carnarvon in south-western South Africa and occupies mainly arid savanna, Succulent- and Nama-Karoo, shrubland and desert (Figure 5b; [41,42]). The eastern limits of the distribution of R. damarensis appears to be demarcated by the area around Taung, the eastern most locality for a specimen in R. damarensis (TM48040, Table S2 and Appendix S 1 in File S1 Supporting Information; Figure 1) and close to the boundary between the Savanna biome in the west and the Grassland biome in the east [41]. The R. damarensis clade comprises two lineages, a northern lineage restricted to the more mesic regions of northern Namibia and a southern lineage with a distribution across several biomes in central and north-western South Africa, extending as far north as central Namibia (Figure 1). The genetic differentiation between the two lineages in R. damarensis is of the same magnitude as that used to infer cryptic species in other rhinolophids e.g. R. arcuatus [61]. In combination with ecological divergence the genetic divergence reported here suggests that R. damarensis may itself consist of cryptic species and further taxonomic revision of both this clade and R. darlingi (sensu lato) is required. Morphological and acoustic convergence Despite the relatively ancient split (~9.7 Mya), marked genetic differentiation and the occupation of different biomes there was convergence in the cranial and post-cranial measurements of R. damarensis and R. darlingi (Figure 3, Table S1 and Appendix S 1 in File S1 Supporting Information) as well as in the noseleaf width and resting echolocation frequency (Table S1 and Appendix S 1 in File S1 Supporting Information). None of these parameters are thus taxonomically informative with respect to differentiating R. damarensis from R. darlingi. The phenotypic similarity between the two darlingi lineages is greater than that between any other pair of species in our analyses (Table 2). Furthermore, R. darlingi is more similar to R. damarensis in body size and echolocation frequency than it is to any of the other species in the fumigatus clade (Figure 2) which all have bigger body sizes and lower resting echolocation frequencies (than both R. darlingi and R. damarensis) ranging from 48–67 mm (forearm length) and 32– 54 kHz, respectively [31, 42]. They are also more similar to each other than either is to the ancestral character state at node B (Figure 2; forearm length = 58.7 mm; resting frequency = 60.1 kHz [39]). Such convergence involving morphology and echolocation in non-sibling species deviates from the pattern normally found in cryptic species of bats in general and rhinolophids in particular. All cryptic bat species uncovered so far have similar morphology but divergent echolocation frequencies which differed by up to 13 kHz (e.g. [19, 20, 62], however see 61). These cryptic species all co-occurred and such differences in sensory traits may be important isolating mechanisms between species [63] leading to resource partitioning and subsequent genetic divergence. At lower echolocation frequencies, where differences in frequency translate into large differences in wavelength [64], habitat and insect prey may be partitioned [27,36,65,66]. At higher frequencies, where differences are unlikely to equate to marked differences in wavelength, resource partitioning may be mediated by the selection for discrete frequency bands to facilitate intraspecific communication [29, 33, 34, 64]. The call frequency of one or more of the co-existing species may shift so that individuals are more sensitive, and will respond preferentially, to the calls of their own species [27, 29], facilitating intraspecific communication. Divergence in echolocation calls in sympatry may therefore be a consequence of competition leading to character displacement in at least one phenotypic trait that permits resource partitioning and coexistence. There is at least one example where sympatric bat lineages converge in both morphology and echolocation [61], attributed to either novel niche partitioning or recent contact. Here lineages within the rhinolophid R. arcuatus may have partitioned their niches in novel ways along dimensions not previously considered. Alternatively, convergence may have evolved in allopatry with the two lineages recently making contact [61]. Strong convergence in allopatry may be a consequence of lineages evolving in the absence of competition from ecologically similar species; their phenotypes being the result of neutral evolution or shaped by selection pressures resulting from occupying similar niches albeit in different biomes. The disjunct distribution of R. damarensis and R. darlingi may allow their morphology and echolocation to converge because they do not compete for foraging space, prey or discrete frequency bands. Such convergence may result from one or more of several processes including inheritance from a common ancestor, adaptation to similar local environments, random genetic drift and shared constraints [5, 67]. Inheritance from a recent common ancestor is unlikely to explain the phenotypic convergence between R. darlingi and R. damarensis. They are placed in different, albeit sister clades: R. damarensis in its own clade and R. darlingi in the fumigatus clade (Figure 2). The two lineages last shared a common ancestor ~9.7Mya, giving rise to numerous lineages comprising individuals that are bigger in size and echolocate at lower frequencies than either R. darlingi and R. damarensis viz. R. fumigatus, R. eloquens and R. hildebrandtii [42]. Similarly, the fact that there are species that share a common ancestor with R. damarensis but that are nevertheless divergent in both morphology and echolocation appears to exclude constraints as an explanation for the convergence. Local adaptation also appears to be an unlikely explanation for the convergence because the two species occur in different biomes and it would be expected that local adaptation would lead to divergence not convergence. It is therefore likely that convergence may be the result of random genetic drift especially since rates of convergence can be high when lineages are diverging only under the influence of genetic drift [6]. Testing this hypothesis would require thorough and integrated analyses of genetic and phenotypic variation in both the damarensis and the fumigatus clades (Figure 2). Nevertheless, there is some evidence that founder effect and random genetic drift may be implicated in the evolution of different body sizes during the diversification of the R. hildebrandtii species-complex [31], one of the lineages in the fumigatus clade – this clade also includes R. darlingi (Figure 2). If so, smaller body size in R. darlingi may have evolved through genetic drift resulting in the convergence of body size between it and R. damarensis, assuming that the ancestral body size of R. damarensis is similar to its current body size. Similar body sizes, coupled with the unique flutter-detection system of rhinolophids [68], would require similar detection distances and levels of flight manoeuvrability that could lead to convergence in wing morphology and echolocation frequency and possibly also insect prey types. This may be especially so given the well-established correlations between body size on the one hand and wing loading, echolocation frequency and bite force, on the other, in bats [63,69–71]. Bite force is in turn correlated with diet [70]. The split between the two damarensis lineages provides further insight into the role of random genetic drift in the evolution of rhinolophids in southern Africa. The split occurred ~5 Mya (Figure 2) which is similar to divergence times reported in many co-distributed taxa including the African four-striped mouse (Rhabdomys pumilio, [72]), the southern rock Agama (Agama atra, [73]) and the gecko, Pachydactylus rugosus [74]. Similarity in the timing of evolutionary diversification amongst co-distributed but diverse taxa is likely a consequence of vicariant evolution [75] and in southern Africa this has been attributed to climate change and subsequent vegetation shifts during the Plio-Pleistocene and Miocene [72–74,76] together with the Plio-Pleistocene uplift of southern Africa's great escarpment and interior plateau [77]. Diversification across these lineages coincided with a period of increased aridity in southern Africa as a result of the interaction in the Miocene between global cooling [78] and tectonic uplift that resulted in a topography which sloped from east to west causing a rainshadow effect across the region [79, 80]. This in turn resulted in an east-west gradient of rainfall and subsequent changes in vegetation which included the contraction of forests, and the expansion of savanna woodlands, grasslands and shrublands [81 – 83] towards the end of the Miocene (7–5Mya). Such climatic oscillations and habitat fluctuation/fragmentation promote diversification of lineages. The diversification of R. damarensis into two distinct mitochondrial lineages may have been caused by disruption to gene flow associated with these changes in biomes especially since the lineages currently occupy separate geographic regions. Given that rates of convergence can be high when lineages diverge under the influence of genetic drift [6] convergence in phenotype in the two damarensis lineages would not be surprising if drift was the dominant process acting during their initial divergence. Testing this hypothesis and the relative influence of the different processes that could bring about convergence can only be elucidated through thorough and integrated analyses of both genetic and phenotypic variation using multiple rapidly and slowly evolving genetic markers, within the context of historical biogeography. In conclusion, cryptic lineages in R. darlingi (sensu lato) appear to have arisen independently and in isolation of each other allowing convergence in both morphology and echolocation. Similarly, cryptic lineage diversification within R. damarensis also appears to have arisen more recently in response to changes in biome boundaries during the Miocene. Although this might be due to vicariant evolution the role of other processes such as adaptation as a result of occupying similar niches cannot be excluded at this stage., Published as part of David S. Jacobs, Hassan Babiker, Anna Bastian, Teresa Kearney, Rowen van Eeden & Jacqueline M. Bishop, 2013, Phenotypic Convergence in Genetically Distinct Lineages of a Rhinolophus Species Complex (Mammalia, Chiroptera), pp. 1-16 in PLoS ONE 8 (12) on pages 12-13, DOI: doi:10.1371/journal.pone.0082614, http://zenodo.org/record/4265355, {"references":["20. 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Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking skeletal bones. The osteoconductive properties of the composite might be improved by adding bone marrow aspirate (BMA), which can be harvested during surgery. Other alternatives to bone graft are demineralised bone matrix (DBM) and human cancellous bone (CB). DBM is prepared by acid extraction of human bone and includes bone collagen, morphogenetic proteins and growth factors. The combination of DBM with CB and with allograft might improve the healing potential of these grafts around non-cemented orthopaedic implants and thereby the implant fixation. Study I investigates the effect of HA/Collagen composite alone and in combination with BMA on the early fixation of porous coated titanium implants. In addition, the study compares also the effect of autograft with the gold standard allograft. By using a sheep model, the implants were inserted in the trabecular bone of femoral condyles. The test biomaterials were placed in a well defined peri-implant gap. After the observation period, the bone-implant specimens were harvested and evaluated mechanically by a destructive push-out test and analyzed histologically qualitatively and quantitatively. Study II investigates the effect of DBM alone and in combination with CB or allograft. The control group in study I and II was allograft. Study III is a methodological study and investigates the potential systematic bias by applying the traditional sampling method, which includes evaluating the mechanical fixation by using the superficial part and the histological analysis by using the profound part of the implant. The implants in this study were inserted in the proximal humerus and only allograft was used in the peri-implant gap. In study I, the mechanical testing showed failure by the preloading in the composite group with and without BMA. There were no bone ongrowth and sparely bone formation in the gap by the composite group. Adding BMA to the composite has no beneficial effect on implant fixation. No significant difference between autograft and allograft on mechanical fixation, bone ongrowth and bone formation. In study II the combination of DBM with CB or allograft showed no significant differences on the mechanical testing and histological analysis to the control group, whereas DBM alone showed significant low mechanical fixation, low bone ongrowth and low bone formation. Study III showed no significant difference between the sampling methods. In conclusion, HA/Collagen composite alone or in combination with BMA has no effect on the early fixation of porous coated titanium implants. Autograft has comparable effect on allograft with regard to early implant fixation. The combination of DBM with CB may represent an alternative to allograft. In study III, mechanical testing and histological analysis can be applied either from the superficial or the profound part of the implant. By applying the histological analysis from the superficial part and the mechanical testing from the profound part, an extra section is required.

Background: Neonatal screening programs for congenital hypothyroidism (CH) are now widespread in developed countries. Aim: Cord blood thyroid-stimulating hormone (TSH) was evaluated for the incidence of CH in Bahrain Defense Force hospital. Methods: Those neonates with cord blood TSH values >25 mU/l were recalled. Permanent CH was reported when the levels of TSH and free T4 (fT4) venous blood samples were ≥15 mU/l and

The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants IN SHEEP Ph.D. Student, Hassan Babiker; Associate Professor, Ph.D. Ming Ding; Professor, dr.med., Soren Overgaard. Department of Orthopaedic Surgery, Odense University Hospital, Odense, Denmark Background: Hydroxyapatite and collagen composites (HA/coll) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effect of newly developed HA/coll-composites with and without bone marrow aspirate (BMA) in order to enhance the fixation of bone implants. Materials and Methods:Titanium alloy implants were inserted into bilateral femoral condyles of 8 skeletally mature sheep, four in each sheep. The implant has a circumferential gap of 2 mm. The gap was filled with: HA/coll; HA/coll-BMA; autograft or allograft. Allograft was served as the control groups. The observation period was 5 weeks. The sheep were euthanized and both femurs were harvested. A push-out mechanical test was performed. A two sample t-test was used. The data are given as mean ± SD. Results:The mechanical testing results were presented as stiffness, shear strength, strain, and failure energy. Autograft/Allograft: Stiffness (MPa) 11.8 ±11.8/4.3 ±3.6 (P = 0.11); strength (MPa) 1.58 ±1.52/0.70 ±0.6 (P = 0.15); Strain (%) 42 ±14/45 ±15 (P = 0.25); Failure Energy kJ/m2 232 ±228/90.4 ±29.5 (P = 0.25) HA/coll and HA/coll-BMA composite were observed with fibrous tissue between the implant and bone. Thus, mechanical testing of these samples was impossible. The autograft group showed a clear trend for greater mechanical values than allograft group but the differences were not significant. This might represent a type two error due to the low number of animals included. Conclusion:We conclude that autogenous bone graft may be more efficient than allograft in the fixation of bone implants, a further study with larger sample size is suggested to reveal this issue. HA/coll composite has no effect on the early fixation of bone implants. Whether there is a long-term effect need to be investigated.

Introduction: Replacement of extensive local bone loss especially in revision joint arthroplasties is a significant clinical challenge. Autogenous and allogenic cancellous bone grafts have been the gold standard in reconstructive orthopaedic surgery, but it is well known that there is morbidity associated with harvesting of autogenous bone graft and limitations in the quantity of bone available. Disadvantages of allograft include the risk of bacterial or viral contamination and non union as well as the potential risk of disease transmission. Alternative options are attractive and continue to be sought. Hydroxyapatite and collagen composites have the potential in mimicking and replacing skeletal bones. Aim: This study attempted to determine the effect of hydroxyapatite/collagen composites in the fixation of bone implants. The composites used in this study is produced by Institute of Science and Technology for Ceramic (ISTEC), Faenza Italy. Material and method: Titanium alloy implants were inserted into the femoral condyles of mature 8 sheep. The implants were inserted extra-articularly into the medial and lateral femoral condyle. Thus four implants were inserted in each sheep. The implant device has a length of 10 mm and a diameter of 6 mm, a footplate and a top washer of 10 mm diameter. The circumferential gap around the cylinder is of 2 mm. The circumferential gaps were filled with the one of the following bone substitute: ISTEC, ISTEC mixed with bone marrow aspirate (BMA), autograft or allograft (control group). The bone marrow was harvested by aspiration from the proximal part of the tibia. Autologous bone graft harvested from the four drill holes in the femoral condyles. A standardised surgical procedure was used. After surgery the sheep were observed at the outdoor facilities of the Biomedical Laboratories, University of Southern Denmark, Odense. The observation period was 5 weeks. The sheeps were euthanized and both of femurs were harvested and sectioned in two parts by using a water-cooled diamond band saw. Specimens for mechanical testing were always taken from the most superficial part of the implant. Specimens are preserving now at - 20°C and wait for the push-out test which is destructive and will be performed on an 858 Bionex MTS hydraulic material testing machine (MTS system cooperation, Minneapolis, Minnesota, USA). The specimens for histological analysis were taken from the more profound part of the implant. They were dehydrated in graded series of ethanol (from 70% to 99%) containing 4% basic fuchin followed by embedding in methylmetacrylate. Sections for histomorphometric analysis using stereological methods in order to get unbiased estimates will be done following.