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Coelacanths were discovered in the Comoros archipelago to the northwest of Madagascar in 1952. Since then, these rare, ancient fish have been found to the south off Mozambique, Madagascar and South Africa, and to the north off Kenya and Tanzania — but it was unclear whether these are separate populations or even subspecies. Here we show that the genetic variation between individuals from these different locations is unexpectedly low. Combined with earlier results from submersible and oceanographic observations, our findings indicate that a separate African metapopulation is unlikely to have existed and that locations distant from the Comoros were probably inhabited relatively recently by either dead-end drifters or founders that originated in the Comoros. [ABSTRACT FROM AUTHOR]

Latimeria chalumnae, a 'living fossil,' is of great scientific interest, as it is closely related to the aquatic ancestors of land-living tetrapods. Latimeria show internal fertilization and bear live young, but their reproductive behaviour is poorly known. Here we present for the first time a paternity analysis of the only available material from gravid females and their offspring. We genotype two L. chalumnae females and their unborn brood for 14 microsatellite loci. We find that the embryos are closely related to each other and never show more than three different alleles per locus, providing evidence for a single father siring all of the offspring. We reconstruct the father's genotype but cannot identify it in the population. These data suggest that coelacanths have a monogamous mating system and that individual relatedness is not important for mate choice.

Background: The prognosis of patients with recurrent, platinum-resistant epithelial ovarian cancer (EOC) is poor. There is no standard treatment available. Emerging evidence suggests a major role for antiangiogenic treatment modalities in EOC, in particular in combination with the metronomic application of low dose chemotherapy. The novel, investigational oral antiangiogenic agent pazopanib targeting vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) and c-kit is currently being studied in different tumour types and is already used as first line therapy in recurrent renal cell carcinoma. A combined therapy consisting of pazopanib and metronomic oral cyclophosphamide may offer a well-tolerable treatment option to patients with recurrent, pretreated EOC., Methods/design: This study is designed as a multicenter phase I/II trial evaluating the optimal dose for pazopanib (phase I) as well as activity and tolerability of a combination regimen consisting of pazopanib and metronomic cyclophosphamide in the palliative treatment of patients with recurrent, platinum-resistant, pre-treated ovarian cancer (phase II). The patient population includes patients with histologically or cytologically confirmed diagnosis of EOC, cancer of the fallopian tube or peritoneal cancer which is platinumresistant or -refractory. Patients must have measurable disease according to RECIST criteria and must have failed available standard chemotherapy. Primary objectives are determination of the optimal doses for pazopanib (phase I) and the overall response rate according to RECIST criteria (phase II). Secondary objectives are time to progression, overall survival, safety and tolerability. The treatment duration is until disease progression or intolerability of study drug regimen (with a maximum of 13 cycles up to 52 weeks per subject)., Discussion: The current phase I/II trial shall clarify the potential of the multitargeting antiangiogenic tyrosinkinaseinhibitor GW 786034 (pazopanib) in combination with oral cyclophosphamide as salvage treatment in patients with recurrent, pretreated ovarian cancer.

Introduction: Unilateral optic neuropathy is commonly due to a prechiasmatic affliction of the anterior visual pathway, while losses in visual hemifields result from the damage to brain hemispheres. Here we report the unusual case of a patient who suffered from acute optic neuropathy following hemispherical subdural hematoma. Although confirmed up to now only through necropsy studies, our case strongly suggests a local, microcirculatory deficit identified through magnetic resonance imaging in vivo., Case Presentation: A 70-year-old Caucasian German who developed a massive left hemispheric subdural hematoma under oral anticoagulation presented with acute, severe visual impairment on his left eye, which was noticed after surgical decompression. Neurologic and ophthalmologic examinations indicated sinistral optic neuropathy with visual acuity reduced nearly to amaurosis. Ocular pathology such as vitreous body hemorrhage, papilledema, and central retinal artery occlusion were excluded. An orbital lesion was ruled out by means of orbital magnetic resonance imaging. However, cerebral diffusion-weighted imaging and T2 maps of magnetic resonance imaging revealed a circumscribed ischemic lesion within the edematous, slightly herniated temporomesial lobe within the immediate vicinity of the affected optic nerve. Thus, the clinical course and morphologic magnetic resonance imaging findings suggest the occurrence of pressure-induced posterior ischemic optic neuropathy due to microcirculatory compromise., Conclusion: Although lesions of the second cranial nerve following subdural hematoma have been reported individually, their pathogenesis was preferentially proposed from autopsy studies. Here we discuss a dual, pressure-induced and secondarily ischemic pathomechanism on the base of in vivo magnetic resonance imaging diagnostics which may remain unconsidered by computed tomography.

Purpose: This randomized, open-label, parallel-group, multicenter study was designed to compare the efficacy and safety of bendamustine and chlorambucil in previously untreated patients with advanced (Binet stage B or C) chronic lymphocytic leukemia (CLL)., Patients and Methods: Patients (

The impact of chromosome architecture in the formation of chromosome aberrations is a recent finding of interphase directed molecular cytogenetic studies. Also positive correlation of translocation frequencies and spatial proximity of chromosomes was described. Thus, disease specific chromosomal translocations could be due to tissue specific genomic organization. However, no three-dimensional interphase fluorescence in situ hybridization (FISH) studies for the nuclear architecture of bone marrow (BM) cells have previously been done. In this study, BM of three secondary acute myelogenous leukemia (AML) cases with trisomy 8 and otherwise normal karyotype were evaluated. Bone marrow cells of one AML and one ALL (acute lymphoblastic leukemia) case, peripheral blood lymphocytes and human sperm, all of them with normal karyotype, served as controls. Multicolor banding (MCB) probes for chromosomes 8 and 21 were applied in suspension-FISH (S-FISH). Interestingly, in myeloid bone marrow cells chromosomes 8 (di- and trisomic) and 21 tended to co-localize with their homologue chromosome(s), rather than to be separated. Thus, the co-localization of chromosomes 8 and 21 might promote a translocation providing a selective advantage of t(8;21) cells in AML-M2. In summary, the concept that tissue specific spatial proximity of chromosomes leads to enhanced translocation frequencies was further supported.

The role of different cytogenetic changes has been extensively evaluated in patients with acute myeloid leukemia (AML), and cytogenetic analysis of AML blasts is essential to form prognostic subgroups in order to stratify for the extent of therapy. Nevertheless, 40-45% of AML patients lack such cytogenetic markers, i.e., cytogenetically normal AML (CN-AML). In the past decade, different molecular aberrations were identified in AML and especially CN-AML can now be discriminated into certain prognostic subgroups. This review considers the latest advances to define the prognostic impact of molecular aberrations in AML and gives insights how such molecular markers can be applied for analysis of minimal residual disease. Furthermore, therapeutic implications as well as the potential role of new methodological techniques in analyzing expression patterns of AML blasts are discussed.

Acute myeloid leukemia (AML) is a heterogeneous disease with respect to clinical prognosis and acquired chromosomal aberrations. After routine banding cytogenetic analysis 45% of AML patients show a normal karyotype (NK-AML). For a better understanding of development and progression in AML, it is important to find markers which could be primary genetic aberrations. Therefore, in this study 31 patients with NK-AML were analyzed by new high resolution molecular cytogenetic approaches. A combination of multitude multicolor banding and metaphase microdissection-based comparative genomic hybridization revealed deletions of the subtelomeric regions in 6% of the studied cases. According to these results, locus-specific probes for the subtelomeric regions of chromosomes 5, 9, 11, 12 and 13 were applied on 22 of the studied 31 NK-AML cases. Surprisingly, 50% of them showed deletions or duplications. These aberrations occurred in the in vitro proliferating as well as in the non-proliferating cells. Meta-analysis of the aberrant regions revealed that they often include genes known to be associated with tumors, e.g. RASA3 on chromosome 13. These results implicate that aberrations in the subtelomeric regions of NK-AML occur quite often and may be considered as primary genetic changes, and should not be neglected in future diagnostic approaches.

Intraspecific group hunting has received considerable attention because of the close links between cooperative behaviour and its cognitive demands. Accordingly, comparisons between species have focused on behaviours that can potentially distinguish between the different levels of cognitive complexity involved, such as "intentional" communication between partners in order to initiate a joint hunt, the adoption of different roles during a joint hunt (whether consistently or alternately), and the level of food sharing following a successful hunt. Here we report field observations from the Red Sea on the highly coordinated and communicative interspecific hunting between the grouper, Plectropomus pessuliferus, and the giant moray eel, Gymnothorax javanicus. We provide evidence of the following: (1) associations are nonrandom, (2) groupers signal to moray eels in order to initiate joint searching and recruit moray eels to prey hiding places, (3) signalling is dependent on grouper hunger level, and (4) both partners benefit from the association. The benefits of joint hunting appear to be due to complementary hunting skills, reflecting the evolved strategies of each species, rather than individual role specialisation during joint hunts. In addition, the partner species that catches a prey item swallows it whole immediately, making aggressive monopolisation of a carcass impossible. We propose that the potential for monopolisation of carcasses by one partner species represents the main constraint on the evolution of interspecific cooperative hunting for most potentially suitable predator combinations., Competing Interests: Competing interests. The authors have declared that no competing interests exist.

Background: Anemia is a phenomenon frequently observed after kidney transplantation and differential diagnosis is broad., Case Report: A 39-year-old woman who had been transplanted a kidney of her father 11 months ago was admitted to the hospital because of severe and worsening anemia (hematocrit [Hct] 0.24). She was under a standard posttransplant immunosuppressive protocol consisting of tacrolimus, mycophenolate mofetil (MMF) and prednisolone. Kidney function was excellent (serum creatinine 118 micromol/l), clinical symptoms of anemia included vertigo, fatigue and low blood pressure. Striking laboratory features were reticulocytopenia (1 per thousand), high ferritin (3,486 microg/l) and low folic acid (4.8 nmol/l), other parameters remained in the normal or therapeutic range. Endoscopic examinations did not reveal any pathologic finding. Bone marrow biopsy, however, showed giant pronormoblasts and the missing of more mature forms as a possible hint to a lack of, e. g., vitamin B(12) (whose serum level was normal, though). After all, the most probable cause of the anemia seemed to be a toxic drug effect and MMF as a possible causative agent was significantly reduced. Nonetheless, the red blood cell count continued to fall (lowest Hct 0.18). On a later outpatient visit all of a sudden positive IgM and IgG antibodies against parvovirus B19 could be detected. Due to a high virus load short-term immunoglobulin treatment was instituted, after which Hct levels rose to normal and virus load decreased to a low degree although still detectable., Conclusion: An infection with parvovirus B19 should always be taken into account as a possible cause of anemia in immunosuppressed patients. Establishing the diagnosis in the acute stage of the disease can be difficult, as antibodies are often negative in these patients and viremia remains the only proof. In most cases a substantial reduction of immunosuppressive therapy is necessary, the infection's relevance for the development of a potentially life-threatening myocarditis is still a matter of debate.

We report on a 72-year-old patient with a clinically diagnosed plasmocytoma which developed to a plasma cell leukemia (PCL) with so far unrecorded complex translocations. As GTG-banding was not able to resolve all karyotypic changes, multiplex-fluorescence in situ hybridization (M-FISH) in combination with microdissection based comparative genomic hybridization (micro-CGH) and multicolor banding (MCB) have been done. Using these molecular cytogenetic approaches the karyotype of the PCL case can be described as: 51,XY,-1,-1,+3,+der(5)t(5;11;1)(5pter right curved arrow 5q13-q14::11q24 right curved arrow 11q25::1q12 right curved arrow 1qter),+7 or +der(7)t(7;1)(7qter right curved arrow 7p15::1p31.1 right curved arrow 1pter),+8,+der(9)t(1;9)(1qter right curved arrow 1q12::9q12 right curved arrow 9pter),der(11)t(1;11;1)(1pter right curved arrow 1p31.1::11p15.5 right curved arrow 11q25::1q12 right curved arrow 1qter),-13,der(14)t(X;14)(Xqter right curved arrow Xq21.3::14pter right curved arrow 14qter),+15,+18,der(19)t(9;19)(9qter right curved arrow 9q12::19q11 right curved arrow 19pter),+i(19)(q10). The case shows one of the most complex karyotypic rearrangements ever described in PCL and indicates two additional chromosomal regions which may contain genes of interest for the development of this hematological disorder: loss of 1p10-p31.1 material and gain of Xq21.3-qter.

We provide selected examples from the fish literature of phenomena found in fish that are currently being examined in discussions of cognitive abilities and evolution of neocortex size in primates. In the context of social intelligence, we looked at living in individualized groups and corresponding social strategies, social learning and tradition, and co-operative hunting. Regarding environmental intelligence, we searched for examples concerning special foraging skills, tool use, cognitive maps, memory, anti-predator behaviour, and the manipulation of the environment. Most phenomena of interest for primatologists are found in fish as well. We therefore conclude that more detailed studies on decision rules and mechanisms are necessary to test for differences between the cognitive abilities of primates and other taxa. Cognitive research can benefit from future fish studies in three ways: first, as fish are highly variable in their ecology, they can be used to determine the specific ecological factors that select for the evolution of specific cognitive abilities. Second, for the same reason they can be used to investigate the link between cognitive abilities and the enlargement of specific brain areas. Third, decision rules used by fish could be used as 'null-hypotheses' for primatologists looking at how monkeys might make their decisions. Finally, we propose a variety of fish species that we think are most promising as study objects.

The lizardCryptoblepharus boutoni cognatus was observed in Madagaskar. The animals descended daily into the intertidal zone to feed there on insects, crustaceans and fish (juvenilePeriophthalmus kohlreuteri). The pattern of activity of the animals is related to the movements of the tides.The lizards have a definite home range and migrate between intertidal feeding area and resting place on land along pathways established by experience. They return to their home even if released at about 200 m from their home range because they seem to acquire a knowledge of the surrounding by occasional exploratory visits. The tendency to establish a home range and homing behaviour are considered as adaptations for life in the intertidal zone, but the lizard remains a purely terrestial animal.