the chromosomes of the cynomolgus macaque macaca fascicularis

The Cynomolgus or crab-eating macaque, Macaca fascicularis (M. irus) has 42 chromosomes. The X chromosome is submetacentric and about 5 % in length of the complement. One of the X chromosomes is very late replicating in the female somatic cells. The other X is also relatively late replicating. The Y chromosome is a minute acrocentric. A short metacentric chromosome was also found to be late replicating. Chromosome no. 20 has an obvious secondary constriction which often associates in a characteristic way. The sex bivalent is identified at pachytene as a characteristic "sex vesicle". At diakinesis it shows an end-to-end association. The mean number of chiasmata per cell was 40 at diakinesis-first metaphase

STABILITY OF ABNORMAL KARYOTYPES IN CELL CULTURE1

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A Variational Perspective on Generative Flow Networks

Generative flow networks (GFNs) are a class of probabilistic models for sequential sampling of composite objects, proportional to a target distribution that is defined in terms of an energy function or a reward. GFNs are typically trained using a flow matching or trajectory balance objective, which matches forward and backward transition models over trajectories. In this work we introduce a variational objective for training GFNs, which is a convex combination of the reverse- and forward KL divergences, and compare it to the trajectory balance objective when sampling from the forward- and backward model, respectively. We show that, in certain settings, variational inference for GFNs is equivalent to minimizing the trajectory balance objective, in the sense that both methods compute the same score-function gradient. This insight suggests that in these settings, control variates, which are commonly used to reduce the variance of score-function gradient estimates, can also be used with the trajectory balance objective. We evaluate our findings and the performance of the proposed variational objective numerically by comparing it to the trajectory balance objective on two synthetic tasks

dna replication patterns of canine chromosomes in vivo and in vitro

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Immunological parameters in girls with Turner syndrome

Disturbances in the immune system has been described in Turner syndrome, with an association to low levels of IgG and IgM and decreased levels of T- and B-lymphocytes. Also different autoimmune diseases have been connected to Turner syndrome (45, X), thyroiditis being the most common. Besides the typical features of Turner syndrome (short stature, failure to enter puberty spontaneously and infertility due to ovarian insufficiency) ear problems are common (recurrent otitis media and progressive sensorineural hearing disorder). Levels of IgG, IgA, IgM, IgD and the four IgG subclasses as well as T- and B-lymphocyte subpopulations were investigated in 15 girls with Turners syndrome to examine whether an immunodeficiency may be the cause of their high incidence of otitis media. No major immunological deficiency was found that could explain the increased incidence of otitis media in the young Turner girls

Pro-apoptotic Bax is the major and Bak an auxiliary effector in cytokine deprivation-induced mast cell apoptosis

The process of apoptosis in immune cells like mast cells is essential to regain homeostasis after an inflammatory response. The intrinsic pathway of apoptosis is ultimately controlled by the pro-apoptotic Bcl-2 family members Bax and Bak, which upon activation oligomerize to cause increased permeabilization of the mitochondria outer membrane leading to cell death. We examined the role of Bax and Bak in cytokine deprivation-induced apoptosis in mast cells using connective tissue-like mast cells and mucosal-like mast cells derived from bax−/−, bak−/− and bax−/−bak−/− mice. Although both Bax and Bak were expressed at readily detectable protein levels, we found a major role for Bax in mediating mast cell apoptosis induced by cytokine deprivation. We analyzed cell viability by propidium iodide exclusion and flow cytometry after deprivation of vital cytokines for each mast cell population. Upon cytokine withdrawal, bak−/− mast cells died at a similar rate as wild type, whereas bax−/− and bax−/−bak−/− mast cells were partially or completely resistant to apoptosis, respectively. The total resistance seen in bax−/−bak−/− mast cells is comparable with mast cells deficient of both pro-apoptotic Bim and Puma or mast cells overexpressing anti-apoptotic Bcl-2. These results show that Bax has a predominant and Bak a minor role in cytokine deprivation-induced apoptosis in both connective tissue-like and mucosal-like mast cells