PD-1-Expressing SARS-CoV-2-Specific CD8+ T Cells Are Not Exhausted,but Functional in Patients with COVID-19

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Transplantation of cultured fetal human adrenal chromaffin cells to rat brain

Adrenal chromaffin cells, obtained from a therapeutically aborted human fetus of about 11 weeks gestation, were cultured for 3 weeks in vitro and then transplanted to the striatum of rats. Transplanted cells became established through strands of tissue growing into the host striatum. No signs of inflammation or rejection were observed up to the time of sacrifice one month post-transplantation. Histofluorescence examination of the implanted areas showed many clusters of cells having an intensely positive catecholamine fluorescence with some of the cells developing conspicuous processes. This study, showing survival of cultured human adrenal chromaffin cells transplanted into rat brain tissue, might indicate the feasibility of using cultured human material for future human neuronal transplantation studies as a therapeutic measure.     

Mouse homologues of the human AZF candidate gene RBM are expressed in spermatogonia and spermatids, and map to a Y chromosome deletion interval associated with a high incidence of sperm abnormalities

An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.      

A new method for assaying adhesion of cancer cells to the greater omentum and its application for evaluating anti-adhesion activities of chemically synthesized oligosaccharides

A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [³H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Galβ1,3[3OMeGalβ1,4GlcNAcβ1,6]αBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells.     

Enhancement of an inhibitory input to the feeding central pattern generator in Lymnaea stagnalis during conditioned taste-aversion learning

To study the neuronal mechanism of a conditioned taste-aversion (CTA) learning in the pond snail Lymnaea stagnalis, we examined the synaptic connection between the neuron 1 medial (N1M) cell and the cerebral giant cell (CGC), the former is an interneuron in central pattern generator for the feeding response and the latter is a regulatory neuron to the central pattern generator. Inhibitory postsynaptic potential (IPSP) which was evoked in the N1M cell by activation of the CGC was larger and lasted longer in the conditioned animal than that in the control animal. The electrical properties of the cell body of CGC and the responses of the CGC to the chemosensory inputs were not changed during the CTA learning. These results, together with the previous report indicating the existence of excitatory projection from the N1M cell to the feeding motoneuron, suggest that enhanced IPSP in the N1M cell may underlie the suppression of feeding responses in the Lymnaea CTA learning.     

Accumulation of somatic hypermutation and antigen-driven selection in rapidly cycling surface Ig+ germinal center (GC) B cells which occupy GC at a high frequency during the primary antihapten response in mice

Well-developed germinal centers (GC) contain rapidly dividing surface immunoglobulin-negative (sIg^-) B cells (centroblasts), and most of their progeny are sIg⁺ B cells (centrocytes) in a resting state. It has been predicted that somatic hypermutation occurs in centroblasts, whereas antigen-driven selection takes place in centrocytes. The present analysis indicates that murine GC B cells bearing sIg with specificity for an immunizing antigen are in a rapidly cycling state and increase exponentially in number to occupy spleen GC at high frequency during the 1st week after primary immunization; however, the number of these cells is significantly reduced in the 2nd week of immunization. During that period, these proliferating sIg⁺ GC B cells accumulate somatic hypermutations with nucleotide exchanges indicative of affinity maturation. These sIg⁺ GC B cells co-express B7-2, ICAM-1, and LFA-1, and have potent antigen-presenting activity which results in T cell activation in vitro. These observations indicate that the sIg⁺ GC B cells accumulate somatic hypermutations and undergo antigen-driven selection through proliferation, probably upon activation by T cells. This sIg⁺ GC B cell population may represent cell cycling centrocytes; however, the possibility that these may represent centroblasts undergoing re-expression of sIg could not be excluded.     

Ehrlich ascites cells activate the alternative pathway of the human complement system

Incubation of Ehrlich ascites cells with normal or C1q or C2 deficient human sera results in killing of the cells. Killing occurred also in the absence of free Ca++, which supported by the fact that factor B and C3 were cleaved, leads to the conclusion that the alternative pathway of the complement system is activated on the surface of the Ehrlich ascites cells.     

Clinical significance of unilateral sinusitis

In general, the etiologic factors of chronic paranasal sinusitis are systemic conditions such as nutrition, predisposition, allergy, and local factors such as nasal anatomic conditions. Among these factors, the development of unilateral sinusitis is a model case verifying the influence of local factors. In my study of 640 cases over a certain period of time, a comparison was made between 161 cases of unilateral sinusitis and 479 cases of bilateral sinusitis in order to verify the effects of local factors in the development of this disease. Patients with a history of previous sinus surgery or tumors were eliminated from the cases. 1. The male-female incidence rate, and the age distribution of the patients at the initial visit showed no prominent differences between unilateral and bilateral cases. 2. It was found that a larger number of cases of unilateral sinusitis had a duration of less than one year as compared to bilateral sinusitis which were longer than and year. Therefore it can be said that the duration of unilateral sinusitis is usually shorter than that of bilateral sinusitis. 3. In unilateral cases the patients with moderate to severe nasal septal deviation, one number of patients with septal deviation towards the diseased side was twice as high as that on the non-affected side. 4. The incidence rate of polyps occurring in the middle meatus was shown to be about twice as high in bilateral cases as in unilateral cases.(ABSTRACT TRUNCATED AT 250 WORDS)