Organotypic hippocampal slice cultures (OHSCs) retain in vivo-like neuronal architecture, synaptic connections, and resident cell populations but gain in vitro advantages of accessibility to ...experimental manipulation and observation. This chapter describes how to prepare OHSCs from neonatal mice to study mechanisms of neuronal damage, including synapse loss and quantifying Aβ-containing axonal swellings from Alzheimer's disease transgenic mice.
•Zinc oxide thin films were prepared using reactive RF magnetron sputtering.•The surface topography was examined using atomic force microscopy (AFM).•Shadowing and surface diffusion, as well as facet ...stabilization, are key mechanisms in the production of the final texture at 100°C.•For the films grown at 250°C, structural misorientation during growth also plays an important role.
In this work, the evolution of the surface morphology of ZnO thin films deposited by reactive RF magnetron sputtering has been investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). All AFM images of the films were analyzed using scaling concepts. To study the growth evolution, different ZnO films with thicknesses of up to 1270nm were deposited at temperatures of 100 and 250°C. For the films grown at 100°C, AFM data show that the lateral length ξ evolves continuously while the temporal evolution of the root mean square roughness σ presents two distinct regimes. Early during the depositions, the morphology of the ZnO films is mainly characterized by granular structures. Beyond thickness of about 600nm, pyramid-like structures with {214} crystallographic facets start to develop. For the films grown at 250°C, however, only one growth regime was observed and for the thicker films, the surface morphology consisted of polygonal structures. For the films grown at 100°C, the growth exponents, β, and the exponent defining the evolution of the characteristic wavelength of the surface, p, were β1=0.70±0.02 and β2=0.26±0.2; and p=0.2±0.04. For the films grown at 250°C, the exponent values were β=0.78±0.02 and p=0.32±0.05. These values of the exponents indicate the occurrence of surface mechanisms, such as shadowing and surface diffusion, as well as facet stabilization at 100°C. For the films grown at 250°C, however, structural misorientation during growth also plays an important role.
The northern white rhino (Ceratotherium simum cottoni) is functionally extinct with only two females left alive. However, cryopreserved material from a number of individuals represents the potential ...to produce additional individuals using advanced reproductive and genetic rescue technologies and perhaps eventually a population to return to their native range. If this could and were done, how should it be done responsibly and thoughtfully. What issues and questions of a technical, bioethical, and societal nature will it raise that need to be anticipated and addressed? Such issues are explored in this article by an interdisciplinary team assembled to provide context to the northern white rhino project of the San Diego Zoo Global.
After ovulation, non-pregnant female giant pandas experience pseudopregnancy. During pseudopregnancy, non-pregnant females exhibit physiological and behavioral changes similar to pregnancy. ...Monitoring hormonal patterns that are usually different in pregnant mammals are not effective at determining pregnancy status in many animals that undergo pseudopregnancy, including the giant panda. Therefore, a physiological test to distinguish between pregnancy and pseudopregnancy in pandas has eluded scientists for decades. We examined other potential markers of pregnancy and found that activity of the acute phase protein ceruloplasmin increases in urine of giant pandas in response to pregnancy. Results indicate that in term pregnancies, levels of active urinary ceruloplasmin were elevated the first week of pregnancy and remain elevated until 20-24 days prior to parturition, while no increase was observed during the luteal phase in known pseudopregnancies. Active ceruloplasmin also increased during ultrasound-confirmed lost pregnancies; however, the pattern was different compared to term pregnancies, particularly during the late luteal phase. In four out of the five additional reproductive cycles included in the current study where females were bred but no birth occurred, active ceruloplasmin in urine increased during the luteal phase. Similar to the known lost pregnancies, the temporal pattern of change in urinary ceruloplasmin during the luteal phase deviated from the term pregnancies suggesting that these cycles may have also been lost pregnancies. Among giant pandas in captivity, it has been presumed that there is a high rate of pregnancy loss and our results are the first to provide evidence supporting this notion.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Population-based evidence on second cancer risk following autologous haematopoietic SCT (HCT) is lacking. We quantified second cancer risk for a national, population-based cohort of adult Australians ...receiving autologous HCT for cancer and notified to the Australasian Bone Marrow Transplant Recipient Registry 1992-2007 (n=7765). Cancer diagnoses and deaths were ascertained by linkage with the Australian Cancer Database and National Death Index. Standardized incidence ratios (SIRs) were calculated and Cox regression models were used to estimate within-cohort risk factors treating death as a competing risk. During a median 2.5 years follow-up, second cancer risk was modestly increased compared with the general population (SIR 1.4, 95% confidence interval 1.2-1.6); significantly elevated risk was also observed for AML/myelodysplastic syndrome (SIR=20.6), melanoma (SIR=2.6) and non-Hodgkin lymphoma (SIR=3.3). Recipients at elevated risk of any second cancer included males, and those transplanted at a younger age, in an earlier HCT era, or for lymphoma or testicular cancer. Male sex, older age (>45 years) and history of relapse after HCT predicted melanoma risk. Transplantation for Hodgkin lymphoma and older age were associated with lung cancer risk. Second malignancies are an important late effect and these results inform and emphasize the need for cancer surveillance in autologous HCT survivors.
Evolution of reproductive seasonality in bears SPADY, THOMAS J; LINDBURG, DONALD G; DURRANT, BARBARA S
Mammal review,
2007, 2007-01, January 2007, 2007-01-00, 20070101, Letnik:
37, Številka:
1
Journal Article
Recenzirano
1. Of the eight species of Ursidae, six are currently at risk of extinction and the remainder face significant risks to their future survival. One of the greatest threats to bears is human-imposed ...environmental alteration (e.g. global warming, chemical pollutants, deforestation). An examination of the reproductive biology and phylogeny of the Ursidae reveals reproductive seasonality as a probable adaptation to adverse environmental conditions. 2. Seven of the eight extant species exhibit distinct mating and birth seasons, with the most ancient species evolving facultative seasonality as an adaptation to the increasingly seasonal climate of the Pliocene. The remainder of the extant species evolved during the Pleistocene glaciations, under conditions of severe seasonal food restriction. Under these conditions, an obligate mode of seasonality emerged and persists to the present. 3. Knowledge of the natural history of seasonal reproduction in the ursids and how it evolved in response to global climatic change provides a context for understanding the ramifications of current environmental change on the reproduction of these important species.
Factors predictive of response to plasma exchange (PE) in treatment of transplantation-associated thrombotic microangiopathy (TA-TMA) are generally poorly understood. To determine any clinical or ...laboratory factors predictive of response to PE in treatment of TA-TMA, we retrospectively reviewed all 11 cases of TA-TMA treated with PE at out institution between December 2001 and March 2008. Response to PE was correlated with associated clinical conditions, grade of TA-TMA, TA-TMA index and lactate dehydrogenase (LDH) level at diagnosis. Overall response to PE was 27%, with three complete responses (CRs) and eight non-responses (NRs) seen. Response to PE was significantly associated with the absence of acute GVHD at TA-TMA diagnosis, with three CR in four patients without active acute GVHD, and NR in seven patients with acute GVHD (P=0.024). There was no significant association seen between response to PE grade of TA-TMA (P=0.179), TA-TMA index (P=0.25) or LDH measurements (P=0.31). Our experience in use of therapeutic PE for management of TA-TMA suggests that PE may indeed be effective in the treatment of this disorder, depending on the clinical circumstance in which it develops. PE is potentially efficacious in the absence of active acute GVHD, and ineffective when acute GVHD is manifest.
All species in the extant Rhinocerotidae family are experiencing increased threats in the wild, making captive populations essential genetic reservoirs for species survival. However, managed species ...face distinct challenges in captivity, resulting in populations that are not self-sustaining. Captive southern white rhinoceros (
) have low reproductive rates and presumed acyclicity is common among females. Although many females fail to ovulate, follicle growth may occur and ovulation can be hormonally induced. Female southern white rhino (
= 6), housed as a bachelorette group, were determined to be ovulatory (
= 1) or anovulatory (
= 5) by serial ultrasound and fecal progestagen analysis. When follicles reached pre-ovulatory size (~35 mm), females (
= 4) were induced to ovulate in 11 trials with a GnRH analog (4.5 mg, SucroMate™) via single intramuscular injection. Nine trials resulted in ovulation (81.8%), all between 36 and 48 hours post-treatment. Ovulations were confirmed by progestagen elevation above baseline coincident with visualization of a corpus luteum (CL). Luteal phases were characterized as short (<50 days) or long (≥50 days). Between short and long cycles, only the number of days of progestagen above baseline was significantly different (
< 0.05), while days with visible luteal structures was not significant (
= 0.11). Both cycle types were observed following both spontaneous and induced ovulations. Furthermore, we showed that longer cycle lengths do not necessarily indicate early pregnancy loss as none of the females were bred or inseminated during the study. While anovulation is common in the southern white rhino captive population, ovulation induction can be achieved efficiently and predictably for use in conjunction with artificial insemination or to facilitate natural breeding. This information will lead to more efficient use of assisted reproductive technologies to overcome reproductive challenges in this species and to generate genetically healthy captive populations as a hedge against extinction.
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