Impact of feed supplement with alfa-amylase and beta-glucanase on ingestive-related biomarkers registered with real-time sensors

The aim of this study was to investigate the impact of feed supplements with alfa-amylase and beta-glucanase (Optipartum C+ 200) on ingestive-related behaviour biomarkers registered with real-time sensors: rumination behaviours and reticulorumen parameters (pH and temperature). Cows (n=20) in the treatment group (TG) were fed with Optipartum C+ 200 (Enzymes feed supplement: Alfa-Amylase 57 Units; Beta-Glucanase 107 Units) from 21 days before calving until 30 days after calving with a feeding rate of 200 g/cow/day. Cows (n=22) in the control group (CG) were fed a feed ration without feed supplement. Measurements started from 6 days before calving and continued until 21 days after calving. The following indicators were registered: with the RumiWatch System: Rumination time; Eating time; Drinking time; Rumination chews; Eating chews; Drinking gulps; Bolus; Chews per minute; Chews per bolus. With the SmaXtec system: the temperature, pH of the contents of the cows' reticulorumens, and cows' walking activity. According to our results, feed supplementation with alfa-amylase and beta-glucanase (Optipartum C+ 200) in the TG group resulted in increases in the following parameters: 9% rumination time and eating time, 19% drinking time, 11% rumination chews, 16% eating chews, 13% number of boluses per rumination, 5% chews per minute and 16% chews per bolus. The rumination time showed a strong, positive relation with rumination chews and bolus indicators in both groups (TG and CG) (p⟨0.001); while the rumination time in both groups of cows showed an opposite direction and was negatively related to eating time and eating chews (p⟨0.05). We found a 1.28 % lower reticulorumen pH and a 0.64 % lower reticulorumen temperature in cows fed with the supplement compared with cows in the control group. Cows in TG were 8.80% more active than those in the CG group. For improvement of ingestive-related behaviour we suggest adding a feed supplement with alfa-amylase and beta-glucanase (Optipartum C+ 200).

Drivers of Infectious Disease Seasonality: Potential Implications for COVID-19

Not 1 year has passed since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19). Since its emergence, great uncertainty has surrounded the potential for COVID-19 to establish as a seasonally recurrent disease. Many infectious diseases, including endemic human coronaviruses, vary across the year. They show a wide range of seasonal waveforms, timing (phase), and amplitudes, which differ depending on the geographical region. Drivers of such patterns are predominantly studied from an epidemiological perspective with a focus on weather and behavior, but complementary insights emerge from physiological studies of seasonality in animals, including humans. Thus, we take a multidisciplinary approach to integrate knowledge from usually distinct fields. First, we review epidemiological evidence of environmental and behavioral drivers of infectious disease seasonality. Subsequently, we take a chronobiological perspective and discuss within-host changes that may affect susceptibility, morbidity, and mortality from infectious diseases. Based on photoperiodic, circannual, and comparative human data, we not only identify promising future avenues but also highlight the need for further studies in animal models. Our preliminary assessment is that host immune seasonality warrants evaluation alongside weather and human behavior as factors that may contribute to COVID-19 seasonality, and that the relative importance of these drivers requires further investigation. A major challenge to predicting seasonality of infectious diseases are rapid, human-induced changes in the hitherto predictable seasonality of our planet, whose influence we review in a final outlook section. We conclude that a proactive multidisciplinary approach is warranted to predict, mitigate, and prevent seasonal infectious diseases in our complex, changing human-earth system.

Disrupted seasonal biology impacts health, food security and ecosystems

The rhythm of life on earth is shaped by seasonal changes in the environment. Plants and animals show profound annual cycles in physiology, health, morphology, behaviour and demography in response to environmental cues. Seasonal biology impacts ecosystems and agriculture, with consequences for humans and biodiversity. Human populations show robust annual rhythms in health and well-being, and the birth month can have lasting effects that persist throughout life. This review emphasizes the need for a better understanding of seasonal biology against the backdrop of its rapidly progressing disruption through climate change, human lifestyles and other anthropogenic impact. Climate change is modifying annual rhythms to which numerous organisms have adapted, with potential consequences for industries relating to health, ecosystems and food security. Disconcertingly, human lifestyles under artificial conditions of eternal summer provide the most extreme example for disconnect from natural seasons, making humans vulnerable to increased morbidity and mortality. In this review, we introduce scenarios of seasonal disruption, highlight key aspects of seasonal biology and summarize from biomedical, anthropological, veterinary, agricultural and environmental perspectives the recent evidence for seasonal desynchronization between environmental factors and internal rhythms. Because annual rhythms are pervasive across biological systems, they provide a common framework for trans-disciplinary research.

Genetic and phenotypically flexible components of seasonal variation in immune function

Animals cope with seasonal variation in environmental factors by adjustments of physiology and life history. When seasonal variation is partly predictable, such adjustments can be based on a genetic component or be phenotypically flexible. Animals have to allocate limited resources over different demands, including immune function. Accordingly, immune traits could change seasonally, and such changes could have a genetic component that differs between environments. We tested this hypothesis in genotypically distinct groups of a widespread songbird, the stonechat (Saxicola torquata). We compared variation in immunity during 1 year in long-distance migrants, short-distance migrants, tropical residents and hybrids in a common garden environment. Additionally, we investigated phenotypically flexible responses to temperature by applying different temperature regimes to one group. We assessed constitutive immunity by measuring hemagglutination, hemolysis, haptoglobin and bactericidal ability against Escherichia coli and Staphylococcus aureus. Genotypic groups differed in patterns of variation of all measured immune indices except haptoglobin. Hybrids differed from, but were rarely intermediate to, parental subspecies. Temperature treatment only influenced patterns of hemolysis and bactericidal ability against E. coli. We conclude that seasonal variation in constitutive immunity has a genetic component, that heredity does not follow simple Mendelian rules, and that some immune measures are relatively rigid while others are more flexible. Furthermore, our results support the idea that seasonal variability in constitutive immunity is associated with variability in environment and annual-cycle demands. This study stresses the importance of considering seasonal variation in immune function in relation to the ecology and life history of the organism of interest.

Clocks for the city: circadian differences between forest and city songbirds

To keep pace with progressing urbanization organisms must cope with extensive habitat change. Anthropogenic light and noise have modified differences between day and night, and may thereby interfere with circadian clocks. Urbanized species, such as birds, are known to advance their activity to early morning and night hours. We hypothesized that such modified activity patterns are reflected by properties of the endogenous circadian clock. Using automatic radio-telemetry, we tested this idea by comparing activity patterns of free-living forest and city European blackbirds (Turdus merula). We then recaptured the same individuals and recorded their activity under constant conditions. City birds started their activity earlier and had faster but less robust circadian oscillation of locomotor activity than forest conspecifics. Circadian period length predicted start of activity in the field, and this relationship was mainly explained by fast-paced and early-rising city birds. Although based on only two populations, our findings point to links between city life, chronotype and circadian phenotype in songbirds, and potentially in other organisms that colonize urban habitats, and highlight that urban environments can significantly modify biologically important rhythms in wild organisms.

An adaptive framework to differentiate receiving water quality impacts on a multi-scale level

The paradigm shift in recent years towards sustainable and coherent water resources management on a river basin scale has changed the subject of investigations to a multi-scale problem representing a great challenge for all actors participating in the management process. In this regard, planning engineers often face an inherent conflict to provide reliable decision support for complex questions with a minimum of effort. This trend inevitably increases the risk to base decisions upon uncertain and unverified conclusions. This paper proposes an adaptive framework for integral planning that combines several concepts (flow balancing, water quality monitoring, process modelling, multi-objective assessment) to systematically evaluate management strategies for water quality improvement. As key element, an S/P matrix is introduced to structure the differentiation of relevant 'pressures' in affected regions, i.e. 'spatial units', which helps in handling complexity. The framework is applied to a small, but typical, catchment in Flanders, Belgium. The application to the real-life case shows: (1) the proposed approach is adaptive, covers problems of different spatial and temporal scale, efficiently reduces complexity and finally leads to a transparent solution; and (2) water quality and emission-based performance evaluation must be done jointly as an emission-based performance improvement does not necessarily lead to an improved water quality status, and an assessment solely focusing on water quality criteria may mask non-compliance with emission-based standards. Recommendations derived from the theoretical analysis have been put into practice.

Attributiveness of a mass flow analysis model for integrated water resources assessment under data-scarce conditions

Nutrients in river systems originate from multiple emission sources, follow various pathways, and are subject to processes of conversion and fate. One approach to tackle this complexity is to apply balance-oriented models. Although these models operate on a coarse temporal and spatial scale, they are capable of assessing the significance of the different emission sources and their results can be the basis for developing integrated water quality management schemes. In this paper we propose and apply a methodology to evaluate the attributiveness of such model results with regard to the modelled emission pathways. The MONERIS (MOdelling Nutrient Emissions in RIver Systems) model is set up, assuming plausible ranges of emission levels from four principal sources. The sensitivity of model performance is computed and related to the contribution from the pathways. The approach is applied for a case study in the upper Western Bug catchment (Ukraine). Coefficient of determination (R(2)) is found insensitive against the model assumptions, at levels around 0.65 for nitrogen and 0.55 for phosphorous emissions. Relative mean absolute error is minimized around 0.2 for both nutrients, but with equifinal combinations of the varied emission pathways. Model performance is constrained by the ranges of the emission assumptions to a limited extent only.

Annual cycles of metabolic rate are genetically determined but can be shifted by phenotypic flexibility

Birds have adjusted their life history and physiological traits to the characteristics of the seasonally changing environments they inhabit. Annual cycles in physiology can result from phenotypic flexibility or from variation in its genetic basis. A key physiological trait that shows seasonal variation is basal metabolic rate (BMR). We studied genetic and phenotypic variation in the annual cycles of body mass, BMR and mass-specific BMR in three stonechat subspecies (Saxicola torquata) originating from environments that differ in seasonality, and in two hybrid lines. Birds were kept in a common garden set-up, under annually variable day length and at constant temperature. We also studied whether stonechats use the proximate environmental factor temperature as a cue for changes in metabolic rate, by keeping birds at two different temperature regimes. We found that the different subspecies kept in a common environment had different annual cycles of body mass, BMR (variance: Kazakh 4.12, European 1.31, Kenyans 1.25) and mass-specific BMR (variance: Kazakh 0.042, European 0.003, Kenyans 0.013). Annual variation in metabolic measures of hybrids was intermediate or similar to that of parental species. Temperature treatment did not affect the shape of the annual cycles of metabolic rate, but metabolic rate was higher in birds kept under the variable temperature regime. The distinct annual cycles in body mass and metabolic rate in stonechat subspecies kept in a common environment indicate different genetic backgrounds rather than merely a phenotypically flexible response to proximate environmental cues. Phenotypic effects of temperature are superimposed on this genetically orchestrated annual cycle.

IWRM decision support with material flow analysis: consideration of urban system input

A review of material flow analysis (MFA) tools, comparison of case studies and analysis of approximately 20 MFA tools (static, semi-empirical models) are performed. The evaluation of the quantification procedures revealed several deficits in the approaches. The following principal complications for a reliable quantification of inputs from the urban water system are identified: (1) frequently insufficient data for urban system model validation (e.g. combined sewer overflow (CSO) discharges); (2) the necessity for additionally quantifying diffuse sources in order to verify modelling results at basin scale, where both input pathways occur, and (3) the contradictions arising when describing the highly dynamic urban system with the help of static MFA models. However, a wise selection of appropriate calculation procedures with regard to the concrete systems characteristics and available data can minimize the model deviations significantly. Criteria and suggestions for designing adapted quantification procedures are given.

Wing pointedness associated with migratory distance in common-garden and comparative studies of stonechats (Saxicola torquata)

Migration promotes utilization of seasonal resources, and the distance flown is associated with specific morphologies, yet these relationships can be confounded by environmental factors and phylogeny. Understanding adaptations associated with migration is important: although migration patterns change rapidly, it is unclear whether migratory traits track behavioural shifts. We studied morphometrics of four stonechat populations representing a migratory gradient and raised under common-garden conditions. With multivariate analyses, we identified wing traits that differed clearly from general size trends, and used phylogenetic comparative methods to test the prediction that these traits correlated with migratory distance in captive and wild populations. Pointedness differed among populations, changed independently from overall body size, and was correlated with migration distance. Migration in stonechats may lead to deviations from allometric size changes, suggesting that birds may adapt morphologically to selection pressures created by their own behaviour in response to changing environmental conditions.

Risk factors for gallstone disease in the laparoscopic era

BACKGROUND

The risk factors for gallstone disease are well known, but they have not been updated to take the development of better ultrasound technology and the advent of laparoscopic surgery into consideration.

METHODS

We compared two groups of patients who underwent ultrasound-one group (n = 100) who underwent cholecystectomy after ultrasound revealed the presence of gallstones and a control group (n = 107) in whom no gallstones were shown on ultrasound.

RESULTS

Seven patients in the control group refused to participate in the study; otherwise, the groups are sequential. Age in the surgery group was 51 years (+/- 16) vs 50 (+/- 16) for the control group. The percentage of female patients was 59% and 52%, respectively (p = ns). Body mass index was 32 (+/- 8) and 28 (+/- 6), respectively (p = 0.013). Parity > 2 was 0.49% and 0.37%, respectively (p = 0.000001). The number who breast-fed at least one child was 17 (24%) and eight (12%), respectively (p = 0.03). Oral contraceptive use was 37 (52%) and 17 (22%), respectively (p = 0.0005). Primary relatives who had had gallbladder surgery was 0.68 (+/- 1) and 0.35 (+/- 0.6), respectively (p = 0.02).

CONCLUSION

Body mass index, breast-feeding, oral contraceptives, parity > 2, and family history were found to be risk factors for gallstone disease. Age and female sex were not, probably due to selection bias.

Differential expression of Rab3 isoforms in high- and low-secreting mast cell lines

The expression of several isoforms of the small-molecular-weight Rab3 GTP-binding proteins is a characteristic feature of all cell types undergoing regulated exocytosis, in which Rab3 proteins are considered to regulate the assembly/disassembly of a fusion complex between granule and plasma membrane in a positive and negative manner through interaction with effector proteins. The pattern of Rab3 protein expression may, therefore, provide a subtle means of regulating exocytosis. To investigate the relationship between Rab3 expression and secretory activity, we assessed the differential expression of individual Rab3 proteins in high- and low-secreting clones of the rat basophilic (RBL) cell line. mRNAs for Rab3 isoforms (a-d) were analyzed by constructing cDNA libraries of high- and low-secreting RBL clones. The relative abundance of mRNAs for Rab3 isoforms was initially determined from the clonal frequency of corresponding cDNA clones. RT-PCR using isoform-specific primers was successfully applied to the quantitation of Rab3a mRNA. The presence of individual Rab3 proteins was revealed by SDS-PAGE and immunoblotting, and also by in situ immunofluorescence confocal microscopy. We present evidence that Rab3a and Rab3c are expressed at high levels in the low-secreting variant, while Rab3d is predominant in the high secretor. Levels of the Rab3 effector proteins, Rabphilin and Noc2, are similar in both RBL cell lines. Subcellular fractionation of unstimulated high and low secretor RBL clones revealed that in both cell types Rab3a has a cytoplasmic location while Rab3d is present in a membrane/organelle fraction containing secretory vesicles. Differences in the pattern of expression of Rab3 isoforms in the two RBL cell lines and their localisation may influence the secretory potential. Furthermore, the presence of Rab3 and effector proteins indicates that the mechanism for regulated exocytosis in cells of mast cells/basophil lineage appears similar to that in pre-synaptic vesicles and pancreatic beta-cells.

[Bacillary angiomatosis of the liver, a suspected ultrasound diagnosis?]

Infections with Bartonella henselae or Bartonella quintana present with vasoproliferative lesions in skin and parenchymatous organs in immunocompromised patients. A case report of a 38-year-old patient with HIV infection and hepatitis B surface antigen status is described. The dominant clinical symptoms in our patient were fever and icterus. Ultrasonography of the abdomen showed a picture similar to that of liver cirrhosis. Irregular (echorich) nodes with hyper-vascularization were suspected to be hepatocellular carcinoma. Ultrasound guided puncture of one of these lesions and histological examination revealed the diagnosis of bartonella infection. Under antibiotic treatment with clarithromycin and doxycycline the fever and the hyperbilirubinemia decreased. The sonographically detectable lesions reduced in size. Vasoproliferative lesions in immunodeficient patients caused by bartonella infection show a characteristic slightly hyperechogenic irregular pattern at ultrasound. Typically, circumscribed hypervascularization might be shown by color Doppler imaging. Liver cirrhosis and diffuse tumor infiltration should be excluded.

Two-dimensional electrophoresis reveals differential protein expression in high- and low-secreting variants of the rat basophilic leukaemia cell line

The aim of this investigation was the identification of cellular proteins that confer a high secretory phenotype on subclones of the rat basophilic leukaemia (RBL) cell line as a model of mast cell regulated degranulation. Following protein separation by two-dimensional (2-D) electrophoresis and silver staining, more than 2000 polypeptide "spots" were resolved reproducibly. Higher sample loads and Coomassie blue staining facilitated the identification by delayed extraction-matrix-assisted laser desorption/ionization (DE-MALDI) mass spectrometry of several polypeptides that were differentially expressed in the high- and low-secreting clones. Several proteins were identified whose expression could contribute to the difference in secretory phenotype. Furthermore, silver-stained 2-D gel patterns suggested differential expression of proteins in the 20-25 kDa and the pI 4.5-7.5 range, characteristic of small guanosine 5'-triphosphate (GTP)-binding proteins. By a combination of "GTP overlay" and immunoblotting, we were able to demonstrate differential expression of small GTP binding-proteins, including Rab3 proteins, in high-and low-secreting clones. The sensitivity of this complementary approach facilitated the detection of some GTP binding and Rab3 proteins, whose expression was not evident in silver-stained 2-D gels.

Blocking of passive sensitization of human mast cells and basophil granulocytes with IgE antibodies by a recombinant human epsilon-chain fragment of 76 amino acids

The recombinant peptide corresponding to residues 301-376 at the junction of constant regions 2 and 3 of the human IgE epsilon chain blocked the in vivo passive sensitization of human skin mast cells and in vitro sensitization of human basophil granulocytes with human IgE antibodies. An injection of the recombinant peptide or E myeloma protein into normal skin sites 1 hr before sensitization with an allergic serum blocked passive sensitization. In this system, approximately 10-fold higher molar concentration of the recombinant peptide than E myeloma protein was required for 50% inhibition of Prausnitz-Küstner reactions. When the mononuclear cells of two normal individuals were preincubated with the recombinant peptide or E myeloma protein for 15 min before passive sensitization with the same allergic serum and the cells were challenged with an optimal concentration of an antigen, approximately 11- to 13-fold higher concentration of the recombinant peptide than E myeloma protein was required for 50% inhibition of antigen-induced histamine release. Further studies with several recombinant peptides indicated that amino acid resides 363-376 in the Fc epsilon-chain fragment are not essential for binding of the peptide to Fc epsilon-chain receptor I.

The B-cell binding site on human immunoglobulin E

Immunoglobulin E comprises the main immunoglobulin class associated with allergy. Its multifarious activities are mediated by two types of Fc receptors found on different cell populations, Fc epsilon R1 on mast cells and basophils, and Fc epsilon R2 on inflammatory cells (monocytes, eosinophils and platelets) and B lymphocytes. Recombinant epsilon-chain fragments synthesized in Escherichia coli have provided the means of mapping the receptor-binding sites on human IgE, and blocking IgE-receptor interactions. We have previously shown that the Fc epsilon R1 binding site is contained within a sequence (Gln 301-Arg 376) spanning the C epsilon 2 and C epsilon 3 domains. Here we show that Fc epsilon R2 can recognize a motif in the C epsilon 3 domain that is formed on dimerization of one or both of the flanking (C epsilon 2 and C epsilon 4) domains. Glycosylation of IgE is not required for the activity of either receptor.

The mast cell binding site on human immunoglobulin E

Antibodies of the immunoglobulin E isotype sensitize mast cells and basophils for antigen-induced mediator release by binding through the Fc portion to a high-affinity receptor (Fc epsilon R1, Ka = 10(9)M-1) on the cell surface causing the clinical manifestations of type I hypersensitivity. As the amino acid sequence of the human epsilon chain is now known, attempts have been made to map the Fc epsilon R1 binding site on IgE to a fragment smaller than Fc epsilon using proteolytic cleavage products, none of which proved to be active. Cleavage between the C epsilon 2 and C epsilon 3 domains released two inactive fragments, suggesting that the junction between these segments could be important in receptor binding. This region is protected against protease digestion in the rat IgE complex with the receptor of rat basophilic leukaemia cells. Here we report the mapping of the mast cell receptor binding site on human IgE to a sequence of 76 amino acids at the C epsilon 2/C epsilon 3 junction. Recombinant peptides containing this sequence inhibit passive sensitization of skin mast cells in vivo and sensitize mast cells to degranulation by anti-IgE in vitro almost as efficiently as a myeloma IgE. Fragments containing the separate domains are inactive. Additional sequences are required for rapid assembly of fragments into disulphide-linked dimers, suggesting that a single chain can form the active site. In a three-dimensional model of the human Fc epsilon, the two identical segments are far apart. Each folds to generate a cleft between the C epsilon 2 and C epsilon 3 domains on the surface of the Fc epsilon. The docking of IgE on to mast cells could take place within this cleft.

Sexual behavior and contraceptive use by adolescent pupils in the republic of bophuthatswana

Cluster sampling was used to identify thirty clusters from which a total random sample of 210 pupils aged thirteen to eighteen were drawn to assess their sexual and contraceptive behavior. The mean age of the sample was 15.2 with a mean age at menarche of 13.8, a mean age at first coital experience of 14.9 and a mean age at commencement of contraception of 15.6. One hundred and seventy-four (82.9%) of the respondents reported general knowledge about contraceptives that was obtained from a variety of sources, 101 (48.1%) reported to be sexually active and thirty-one (14.8%) to be using contraceptives. Although no statistically significant relationship was found between age and contraceptive use, a statistically significant correlation (p < .001) was found between age and age at first coitus.

Biological properties of a recombinant human immunoglobulin epsilon-chain fragment

A recombinant human immunoglobulin epsilon-chain gene expression product (rFc epsilon) was compared with a human E myeloma protein in the affinity for epsilon-chain Fc fragment receptors (Fc epsilon R) on cultured human basophils. The association-dissociation kinetics of the rFc epsilon-Fc epsilon R interaction are indistinguishable from that of E myeloma protein, indicating that rFc epsilon and IgE have identical affinity for the receptors. The recombinant gene product sensitizes cultured basophils for anti-IgE-induced histamine release. A dose-response curve of histamine release indicates that the gene product is equally efficient in transducing the signal for degranulation as the natural IgE. Both the rFc epsilon and IgE lost the affinity for Fc epsilon R by heating at 56 degrees C. Upon renaturation by passage through a solution of 6 M guanidine hydrochloride, rFc epsilon recovered both the affinity for Fc epsilon R and the original CD spectra. On the other hand, renaturation of heat-denatured IgE largely restored optical activity above 250 nm but restored neither the affinity for Fc epsilon R nor the CD spectrum below 220 nm. The results suggest that either the amino acid sequence or the carbohydrate present in the myeloma protein, but not the rFc epsilon, may interfere with refolding of the receptor-binding structures.

Inhibition of the Prausnitz-Küstner reaction by an immunoglobulin epsilon-chain fragment synthesized in E. coli

The Prausnitz-Küstner (P-K) reaction is a sensitive test for the presence and activity in the skin of immunoglobulin E, an important class of immunoglobulin mediating allergic reactions. A fragment of the human myeloma ND epsilon-chain gene, encoding the second, third and fourth domains of the IgE constant region (C epsilon 2-4) was assessed here for its ability to inhibit the P-K reaction in vivo. Injection of the fragment in skin sites of healthy human adults prevented subsequent sensitization with serum containing IgE antibody to ragweed antigen. Inhibition of the P-K reaction required a 200-fold molar excess of the C epsilon fragment over the IgE present in the sensitizing serum. The efficacy of the C epsilon fragment in inhibiting the P-K reaction compared favourably with that of natural myeloma IgE (PS) in terms of both blocking concentrations and duration of the blocking effect. The inhibition of the P-K reaction by C epsilon 2-4 fragments was specific and probably caused by the saturation of IgE receptors on mast cells by the recombinant gene product.

Properties of a human immunoglobulin epsilon-chain fragment synthesized in Escherichia coli

A fragment of the cloned gene for the human myeloma ND epsilon chain, coding for the second, third, and fourth domains of the immunoglobulin, has been coupled to the tryptophan control region of an expression plasmid and subcloned in Escherichia coli. Induction of gene expression results in the synthesis of the expected, antigenically active polypeptide of Mr 40,000, which constitutes 18% of total bacterial protein and yields 55 mg/liter of culture. The immunoglobulin, which is aggregated and packed into large inclusion bodies within the bacterial cell, can be dissolved by denaturing solvents and purified by affinity chromatography using anti-IgE Sepharose. Reduced monomeric chains assemble spontaneously into dimers. On assay to measure the inhibition of binding of 125I-labeled human E myeloma protein to Fc epsilon receptors on cultured human basophils, the cloned gene product exhibited 20% of the activity of the native protein.

Occurrence of a blood group A-like substance in eggs of the prosobranch snail Pomacea canaliculata

In the eggs of the prosobranch snails Pomacea canaliculata and Pomacea insularum a blood group A-like substance has been detected by anti-A from the snails Helix pomatia, Helix aspersa and Cepaea nemoralis.