A model for cleavage ofO-glycosidic bonds in glycoproteins

The present work investigated the possibility of cleavage of -linkages between mannose or galactose and serine/threonine residues by -mannosidase and -galactosidase. The study was carried out initially with model synthetic compounds imitating theO-glycosidic bond in glycoproteins, and further with glucoamylase. It was shown that -mannosidase and -galactosidase can hydrolyse these linkages after proteolytic digestion of glucosamylase.     

Nitrification,denitrification, and related functional genes under elevated CO2: A meta-analysis in terrestrial ecosystems

Global change may have profound effects on soil nitrogen (N) cycling that can induce positive feedback to climate change through increased nitrous oxide (N₂O) emissions mediated by nitrification and denitrification. We conducted a meta-analysis of the effects of elevated CO₂ on nitrification and denitrification based on 879 observations from 58 publications and 46 independent elevated CO₂ experiments in terrestrial ecosystems. We investigated the effects of elevated CO₂ alone or combined with elevated temperature, increased precipitation, drought, and N addition. We assessed the response to elevated CO₂ of gross and potential nitrification, potential denitrification, and abundances of related functional genes (archaeal amoA, bacterial amoA, nirK, nirS, and nosZ). Elevated CO₂ increased potential nitrification (+28%) and the abundance of bacterial amoA functional gene (+62%) in cropland ecosystems. Elevated CO₂ increased potential denitrification when combined with N addition and higher precipitation (+116%). Elevated CO₂ also increased the abundance of nirK (+25%) and nirS (+27%) functional genes in terrestrial ecosystems and of nosZ (+32%) functional gene in cropland ecosystems. The increase in the abundance of nosZ under elevated CO₂ was larger at elevated temperature and high N (+62%). Four out of 14 two-way interactions tested between elevated CO₂ and elevated temperature, elevated CO₂ and increased precipitation, and elevated CO₂ and N addition were marginally significant and mostly synergistic. The effects of elevated CO₂ on potential nitrification and abundances of bacterial amoA and nirS functional genes increased with mean annual temperature and mean annual precipitation. Our meta-analysis thus suggests that warming and increased precipitation in large areas of the world could reinforce positive responses of nitrification and denitrification to elevated CO₂ and urges the need for more investigations in the tropical zone and on interactive effects among multiple global change factors, as we may largely underestimate the effects of global change on soil N₂O emissions.     

Microbial nitrogen and phosphorus co-limitation across permafrost region

The status of plant and microbial nutrient limitation have profound impacts on ecosystem carbon cycle in permafrost areas, which store large amounts of carbon and experience pronounced climatic warming. Despite the long-term standing paradigm assumes that cold ecosystems primarily have nitrogen deficiency, large-scale empirical tests of microbial nutrient limitation are lacking. Here we assessed the potential microbial nutrient limitation across the Tibetan alpine permafrost region, using the combination of enzymatic and elemental stoichiometry, genes abundance and fertilization method. In contrast with the traditional view, the four independent approaches congruently detected widespread microbial nitrogen and phosphorus co-limitation in both the surface soil and deep permafrost deposits, with stronger limitation in the topsoil. Further analysis revealed that soil resources stoichiometry and microbial community composition were the two best predictors of the magnitude of microbial nutrient limitation. High ratio of available soil carbon to nutrient and low fungal/bacterial ratio corresponded to strong microbial nutrient limitation. These findings suggest that warming-induced enhancement in soil nutrient availability could stimulate microbial activity, and probably amplify soil carbon losses from permafrost areas.     

Synaptosomal non-mitochondrial ATPase activities and drug treatment

Energy-using non-mitochondrial ATPases were assayed in rat cerebral cortex synaptosomes and synaptosomal subfractions, namely synaptosomal plasma membranes and synaptic vesicles. The following enzyme activities were evaluated: Na⁺, K⁺-ATPase; high- and low-affinity Ca²⁺-ATPase; basal Mg²⁺-ATPase; Ca²⁺, Mg²⁺-ATPase. The evaluations were performed after four week-treatment with saline [controls] or -adrenergic agents (-yohimbine, clonidine), energymetabolism interfering compound (theniloxazine), and oxygen-partial pressure increasing agent (almitrine), in order to define the plasticity and the selective changes in individual ATPases. In rat cerebral cortex, the enzyme adaptation to four-week-treatment with -yohimbine or clonidine was characterized by increase in both high- and low-affinity Ca²⁺-ATPase activities. The action involves the enzyme form located in the synaptic plasma membranes. The enzyme adaptation to the subchronic treatments with theniloxazine or almitrine was characterized by increase in Na⁺, K⁺-ATPase or Mg²⁺-ATPase activities, respectively. The action involves the enzymatic forms located in the synaptic plasma membranes. Thus, the pharmacodynamic effects of the agents tested should also be related to the changes induced in the activity of some specific synaptosomal nonmitochondrial ATPases.     

Recognition of the Qa-2k tumor antigen by T cell receptor γ/δ of an immunopotentiator-induced tumoricidal T cell of mice

Tumor-specific expression of Qa-2^k antigen coded by the Q5^k gene on various mouse tumor cells and immunological response of the host mice to the antigen have been demonstrated [Seo et al. (1992) J Exp Med 175: 547; Tanino et al. (1992) Cancer Immunol Immunother 35: 230]. The possibility was examined that Qa-2 antigen is one of the recognition target molecules of immunopotentiator-induced, H-2-nonrestricted tumoricidal lymphocytes of Qa-2^– mice. Lymphocytes stimulated in vivo withP. acnes or culture-induced anomalous killers of B6.K1 mice did not exhibit significant in vitro cytotoxicity against B6.K1 lymphoblasts but lysed their Qa-2,3-congenic counterpart B6 lymphoblasts. To demonstrate the Qa-2 specificity of such cytotoxic cells more precisely, an L cell transformant clone (L^Q7b/Kb), which expressed the 1 and 2 domains of the Qa-2 antigen (Q7^b gene product), was generated by transfecting a cloned plasmid DNA containing a hybrid gene constructed from the 5 half of the Q7^b gene and the 3 half of the H-2K^b gene (pQ7^b/K^b). Using L^Q7b/Kb cells as the target cells and the nylon-wool-nonadherent fraction of lymphocytes fromP. acnes-stimulated (C3H/He × B6.K1)F1 mice (H-2^k, Qa-2^–) as the effector cells of the in vitro cytotoxicity reaction, the presence of cytotoxic cells that recognize the 1/2 region of the Q7^b gene product was demonstrated. The cytotoxic activity was dependent on T cells bearing T cell receptors of the / type (TCR/). The (C3H/He × B6.K1)F1 effector cells, as well as the B6.K1 effector cells also lysed BW5147 lymphoma cells (Qa-2^k+) derived from AKR mice (Qa-2^–, H-2^k). By target-competition experiments it was shown that some of the effector cells lytic to BW5147 were identical to those that lysed L^Q7b/Kb. Therefore some of the tumoricidal cells induced by the immunopotentiator interact with the target tumor cells through recognition of the 1/2 region of the Qa-2^k tumor antigen by TCR/.     

根系去除改变了毛竹林土壤酶活性对氮磷添加的响应

亚热带是我国氮和磷沉降的热点地区,森林生态系统碳（C）、氮（N）、磷（P）循环对N和P沉降的响应受到广泛关注。根系作为森林土壤碳和养分持续供给的重要来源,其输入变化在N和P沉降下通过影响土壤酶活性进而调控土壤碳和养分循环过程。以毛竹林为研究对象,选择硝酸铵和磷酸二氢钠分别进行N和P添加,共设置4个处理：对照、N添加、P添加和N+P添加,并结合壕沟处理,探究毛竹林土壤C、N、P循环相关酶活性对氮磷添加和根系去除的响应,并分析它们与土壤和细根化学性质之间的关系。结果表明：土壤C、N循环相关酶活性整体上对根系去除的响应比氮磷添加更敏感,这主要是因为根系去除显著降低土壤全氮和铵态氮含量,但短期氮磷添加并未显著改变调控土壤酶活性分异的土壤有机碳、全氮和铵态氮含量。与C、N循环相关酶活性不同,土壤P循环相关酶对根系去除和磷添加处理均呈现负响应,这可能是因为阻断根系P吸收和补充土壤P元素降低了微生物的P开采作用。但研究区土壤微生物仍受到P限制作用,这是因为在P缺乏毛竹林生态系统,根系比微生物具有更强的P吸收利用能力。研究结果强调了不同功能土壤酶活性对土壤养分添加和根系输入变化响应的敏感性差异,为预测低P毛竹林生态系统土壤C和养分循环提供依据。     

Immunogenicity,effectiveness and safety of COVID-19 vaccine in older adults living in nursing homes: A real-life study

IntroductionBNT162b2 (BioNTech and Pfizer) is a nucleoside-modified mRNA vaccine that provides protection against SARS-CoV-2 infection and is generally well tolerated. However, data about its efficacy, immunogenicity and safety in people of old age or with underlying chronic conditions are scarce.PurposeTo describe BNT162b2 (BioNTech and Pfizer) COVID-19 vaccine immunogenicity, effectiveness and reactogenicity after complete vaccination (two doses), and immunogenicity and reactogenicity after one booster, in elders residing in nursing homes (NH) and healthy NH workers in real-life conditions.MethodsObservational, ambispective, multicenter study. Older adults and health workers were recruited from three nursing homes of a private hospital corporation located in three Spanish cities. The primary vaccination was carried out between January and March 2021. The follow-up was 13 months. Humoral immunity, adverse events, SARS-CoV-2 infections, hospitalizations and deaths were evaluated. Cellular immunity was assessed in a participant subset.ResultsA total of 181 residents (mean age 84.1 years; 89.9% females, Charlson index ≥2: 45%) and 148 members of staff (mean age 45.2 years; 70.2% females) were surveyed (n:329). After primary vaccination of 327 participants, vaccine response in both groups was similar; ≈70% of participants, regardless of the group, had an antibody titer above the cut-off considered currently protective (260 BAU/ml). This proportion increased significantly to ≈ 98% after the booster (p < 0.0001 in both groups). Immunogenicity was largely determined by a prior history of COVID-19 infection. Twenty residents and 3 workers were tested for cellular immunity. There was evidence of cellular immunity after primary vaccination and after booster. During the study, one resident was hospitalized for SARS-CoV-2. No SARS-CoV-2-related deaths were reported and most adverse events were mild.ConclusionsOur results suggest that the BNT162b2 mRNA COVID-19 vaccine is immunogenic, effective and safe in elderly NH residents with underlying chronic conditions.     

Developing new hospital-at-home models based on Comprehensive Geriatric Assessment: Implementation recommendations by the Working Group on Hospital-at-Home and Community Geriatrics of the Catalan Society of Geriatrics and Gerontology

Last decade, the Government of Catalonia have urged an integrated care strategy for planning the care model to older populations living with frailty, multimorbidity and advanced illnesses. Based on international evidence that was reviewed by a group of experts from the Catalan Society of Gerontology and Geriatrics, we summarised some recommendation to adapt hospital-at-home care to older populations in our system. We defined Comprehensive Geriatric Assessment (CGA) hospital-at-home (HaH) as a specialised home hospitalisation service formed by interdisciplinary teams, characterised by using the clinical methodology of CGA, and by adapting geriatric units’ protocols for the provision of person-centred care at home. Main benefits of CGA-HaH in these populations are: response to heath crises according to individualised care plans based on the situational diagnosis carried out by Primary Care teams; provision of a comprehensive health and social approach tailored to the complexity of cases and situations; and adaptation of multipurpose hospitalisation, by working on different person-centred care, aspects, such as caregivers support on care provision, focusing on function or home adaptation.     

The water frogs of Greece: Bioacoustic evidence for a new species

The structure of the mating call of lake frogs (referred to as R. ridibunda) from 16 populations in Greece was analyzed for local variation using multivariate statistics. The populations of Thrace and of the island of Samothraki form a group giving the same type of mating call, whereas the mating call of the other populations differs in the degree of temperature dependence of four parameters, and specifically in the number of pulses/pulse group and pulse groups/call. Discriminant functions distinguish even single call series with a probability of 97%, intermediate mating calls are absent, and there is a significant, but slight differentiation of external morphological characters. These results have strong taxonomic implications. We conclude that the lake frogs of Greece comprise two species. The mating call of the lake frogs from Thrace resembles in all parameters that of the Rana ridibunda in the terra typica restricta (Guryev, CIS). Accordingly, the lake frogs of eastern Greece belong to R. ridibunda. The mating call of these lake frogs consists of 20 pulses/pulse group and of 7 pulse groups/call on the average. Most of Greece is inhabited by the second taxon, Rana balcanica sp. n. Its mating call is characterized by 27 pulses/pulse group and 4 pulse groups/call on the average. The two species in Greece do not differ with respect to coloration and size, but several standardized indices vary significantly: body length/digitus primus length; body length/callus internus length; body length/snout-eye distance; body length/tympanum diameter; tibia length/callus internus length; maximal head width/snout-eye distance.