Miracle-dz/UniFAR-FTUs huggingface dataset:
Noncovalent Immobilization of Streptavidin on In Vitro- and In Vivo-Biotinylated Bacterial Magnetic Particles

ABSTRACT Biotinylated magnetic nanoparticles were constructed by displaying biotin acceptor peptide (BAP) or biotin carboxyl carrier protein (BCCP) on the surface of bacterial magnetic particles (BacMPs) synthesized by Magnetospirillum magneticum AMB-1. BAP-displaying BacMPs (BAP-BacMPs) were extracted from bacterial cells and incubated with biotin and Escherichia coli biotin ligase. Then the in vitro biotinylation of BAP-BacMPs was confirmed using alkaline phosphatase-labeled antibiotin antibody. In contrast, BacMPs displaying the intact 149 residues of AMB-1 BCCP (BCCP-BacMPs) and displaying the COOH-terminal 78 residues of BCCP (BCCP78-BacMPs) were biotinylated in AMB-1 cells. The in vivo biotinylation of BCCP-BacMPs and BCCP78-BacMPs was thought to be performed by endogenous AMB-1 biotin ligase. Streptavidin was introduced onto biotinylated BacMPs by simple mixing. In an analysis using tetramethyl rhodamine isocyanate-labeled streptavidin, approximately 15 streptavidin molecules were shown to be immobilized on a single BCCP-BacMP. Furthermore, gold nanoparticle-BacMP composites were constructed via the biotin-streptavidin interaction. The conjugation system developed in this work provides a simple, low-cost method for producing biotin- or streptavidin-labeled magnetic nanoparticles. Various functional materials can be site selectively immobilized on these specially designed BacMPs. By combining the site-selective biotinylation technology and the protein display technology, more innovative and attractive magnetic nanomaterials can be constructed.
Plant Circadian Clocks Increase Photosynthesis, Growth, Survival, and Competitive Advantage

Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long– and short–circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control.
Production and characterization of polyclonal and monoclonal antibodies to rat brain L-glutamate decarboxylase.

Specific monoclonal and polyclonal antibodies to rat brain glutamate decarboxylase (GAD) were produced and characterized. Polyclonal antibodies against GAD were raised in rabbits by injecting a total of 70-210 micrograms of purified GAD i.m. The specificity of anti-GAD serum was established from a variety of tests including Ouchterlony immunodiffusion, immunoelectrophoresis, immunoprecipitation, dot immunoassay, ELISA tests and Western immunoblottings. In immunodiffusion and immunoelectrophoresis tests using partially purified GAD preparations and anti-GAD serum a single, sharp precipitin line corresponding to GAD activity was obtained. Quantitative immunoprecipitation of GAD activity was achieved using anti-GAD IgG and Staphylococcus aureus. Specificity of the antiserum was further indicated from a dot immunoassay and ELISA tests in which the intensity of the reaction product was proportional to the amount of GAD protein present. In the Western immunoblotting experiments using partially purified GAD preparations only two protein bands corresponding to the position of the two subunits of GAD were stained by anti-GAD IgG, further supporting the specificity of polyclonal antibodies against GAD. In addition to polyclonal antibodies, several specific GAD-antibodies-producing clones were also obtained by the hybridoma technique. The specificity of monoclonal antibodies against GAD were established from the following criteria: positive on ELISA test using homogeneous GAD as antigen; formation of GAD--anti-GAD IgG complex as indicated from gel filtration chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis; and specific recognition of GAD subunit in a partially purified GAD preparation in Western immunoblotting test. Monoclonal antibodies were further characterized by immunohistochemical localization of known GABAergic neurons and their processes in the cerebellum and retina.
Modulation of Estrogen Receptor α Function and Stability by Tamoxifen and a Critical Amino Acid (Asp-538) in Helix 12*

Estrogen receptor α (ER) is a ligand-activated transcription factor implicated in breast cancer growth. Selective estrogen receptor modulators (SERMs), such as tamoxifen (4-OHT), bind to the ER and affect the position of helix 12, thereby influencing coregulator binding and ER transcriptional activation. Previous studies have shown that a triple mutation in helix 12 (3m; D538A/E542A/D545A) caused a change in ER stability and obliterated 4-OHT action (Liu, H., Lee, E. S., de los Reyes, A., Zapf, J. W., and Jordan, V. C. (2001) Cancer Res. 61, 3632–3639). Two approaches were taken to determine the role of individual mutants (D538A, L540Q, E542A, and D545A) on the activity and stability of the 4-OHT·ER complex. First, mutants were evaluated using transient transfection into ER-negative T47D:C4:2 cells with an ERE3-luciferase reporter, and second, transforming growth factor α (TGFα) mRNA was used as a gene target in situ for stable transfectants of MDA-MB-231 cells. Transcriptional activity occurred in the presence of estrogen in all of the mutants, although a decreased response was observed in the L540Q, 3m, and D538A cells. The 3m and D538A mutants lacked any estrogenic responsiveness to 4-OHT, whereas the other mutations retained estrogen-like activity with 4-OHT. Unlike the other mutants, the ER was degraded in the D538A mutant with 4-OHT treatment. However, increasing the protein levels of the mutant with the proteasome inhibitor MG132 did not restore the ability of 4-OHT to induce TGFα mRNA. We suggest that Asp-538 is a critical amino acid in helix 12 that not only reduces the estrogen-like actions of 4-OHT but also facilitates the degradation of the 4-OHT·D538A complex. These data further illustrate the complex role of specific surface amino acids in the modulation of the concentration and the estrogenicity of the 4-OHT·ER complex.
Lipopolysaccharide Binding Protein Is a Potential Marker for Invasive Bacterial Infections in Children

Background: The aim of this study was to test the hypothesis that elevated lipopolysaccharide binding protein (LBP) serum concentration is a useful marker in the early diagnosis of invasive bacterial infection in children. We measured LBP in serum and cerebrospinal fluid (CSF) of children with proven invasive infection caused by Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis. Patients and Methods: Samples were collected from 39 children (aged 2 months to 17 years) with bacterial sepsis (n = 19) or meningitis (n = 20). Bacterial infection was diagnosed when a blood or CSF culture was positive and clinical signs of invasive infection were present. The control group consisted of serum (n = 60) and CSF (n = 19) samples from children with neurologic disease, juvenile idiopathic arthritis or viral infection. In 10 patients with bacterial infection, follow-up samples (24 and 48 hours) were available. LBP values were measured by an immunochemiluminescence analyzer (IMMULITE; DPC Biermann, Bad Nauheim, Germany) and compared with tumor necrosis factor-α and interleukin-8 concentrations. Results: The median LBP serum concentrations in patients with bacterial infection were markedly elevated compared with the control groups (45.0 [33.1–55.2] versus 8.3 [6.8–10.1] &mgr;g/mL [median and 5–95% confidence interval]; P < 0.0001). Follow-up serum values of LBP were persistently elevated despite adequate antibiotic treatment, whereas tumor necrosis factor-α and interleukin-8 concentrations decreased. In contrast, LBP concentrations in the CSF were below the detection limit of 0.5 &mgr;g/mL in 67% of patients with bacterial meningitis (median <0.5 &mgr;g/mL), whereas tumor necrosis factor-α and interleukin-8 levels were highly elevated. Conclusion: LBP serum concentration is elevated in serum of children with invasive bacterial infection and could be a promising diagnostic marker.
Selective Requirement for CD40-CD154 in Drug-Induced Type 1 Versus Type 2 Responses to Trinitrophenyl-Ovalbumin1

CD154 is transiently expressed by activated T cells and interacts with CD40 on B cells, dendritic cells, macrophages, and monocytes. This costimulatory receptor-ligand couple seems decisive in Ag-driven immune responses but may be differentially involved in type 1 vs type 2 responses. We studied the importance of CD40-CD154 in both responses using the reporter Ag popliteal lymph node assay in which selectively acting drugs generate clearly polarized type 1 (streptozotocin) or type 2 (D-penicillamine, diphenylhydantoin) responses to a constant coinjected Ag in the same mouse strain. Treatment of mice with anti-CD154 reduced characteristic immunological parameters in type 2 responses (B and CD4+ T cell proliferation, IgG1 and IgE Abs, and IL-4 secretion) and only slightly affected the type 1 response (small decrease in IFN-γ production, influx of CD11c+ and F4/80+ cells, and prevention of architectural disruption of the lymph node, but no effect on IgG2a Ab and TNF-α secretion or B and CD4+ T cell proliferation). The findings indicate that the CD40-CD154 costimulatory interaction is a prerequisite in drug-induced type 2 responses and is only marginally involved in type 1 responses. The observed expression patterns of CD80 and CD86 on different APC (B cells in type 2 and dendritic cells in type 1) may be responsible for this discrepancy.
Elaborated learning in undergraduate medical education

Summary. Southampton Medical School holds its major examination of basic knowledge after rather than before students enter their first clinical attachments. An interview survey investigated its educational effects, and found that students adopt one of four revision approaches. The most successful, not just in terms of examination grade but more particularly in students' subsequent ability to retrieve and use the knowledge gained, occurred when students related their preclinical revision to their clinical experiences. One of these approaches, an elaboration of knowledge, is considered to be essential for effective clinical thinking yet is probably rare elsewhere in medical education since it appears to be a consequence of a particular curricular arrangement. An explanation is given in terms of current thinking in cognitive psychology, and this challenges the theoretical assumptions on which other research in medical education has been uncritically based. Some implications for medical education and further research are discussed.
Male Reproductive Tract Lesions at 6, 12, and 18 Months of Age Following in Utero Exposure to Di(n-butyl) Phthalate

In utero exposure of male rats to the antiandrogen di(n-butyl) phthalate (DBP) leads to decreased anogenital distance (AGD) on postnatal day (PND) 1, increased areolae retention on PND 13, malformations in the male reproductive tract, and histologic testicular lesions including marked seminiferous epithelial degeneration and a low incidence of Leydig cell (LC) adenomas on PND 90. One objective of this study was to determine the incidence and persistence of decreased AGD, increased areolae retention, and LC adenomas in adult rats following in utero DBP exposure. A second objective was to determine whether AGD and areolae retention during the early postnatal period are associated with lesions in the male reproductive tract. Pregnant Crl:CD(SD)BR rats were gavaged with corn oil or DBP at 100 or 500 mg/kg/day, 10 dams per group. Three replicates of rats (n = 30 rats per replicate) were exposed from gestation day 12 to 21 and the male offspring allowed to mature to 6, 12, or 18 months of age. Gross malformations in the male reproductive tract and histologic lesions in the testes were similar to those previously described. However, testicular dysgenesis, a lesion of proliferating LCs and aberrant tubules that has not been previously described in DBP-exposed testes, was diagnosed. The incidence of this lesion was approximately 20% unilateral and 7—18% bilateral in the high-dose group and was similar among all ages examined, implicating a developmental alteration rather than an age-related change. AGD and areolae retention were found to be permanent changes following in utero exposure to 500 mg/kg/day of DBP. Decreased AGD was a sensitive predictor of lesions in the male reproductive tract, relatively small changes in AGD were associated with a significant incidence of male reproductive malformations. In utero DBP exposure induced proliferative developmental lesions, some of which would have been diagnosed as LC adenomas by the morphological criteria set forth by the Society of Toxicologic Pathology. However, these lesions were dissimilar to traditional LC adenomas as the LCs were poorly differentiated and the lesions contained aberrant seminiferous tubules. While the morphology and incidence of this DBP-induced testicular developmental lesion has been fully characterized by this study, the detailed pathogenesis warrants further investigation.
Identification of secernin 1 as a novel immunotherapy target for gastric cancer using the expression profiles of cDNA microarray

Despite the discovery of multiple TAAs, only a limited number is available for clinical application, particularly against epithelial malignancies. In this study we searched for novel TAAs using expression profiles of gastric cancer examined with cDNA microarray, and identified the SCRN1 gene as a candidate. SCRN1 was confirmed to be expressed in five out of seven gastric cancers with semiquantitative RT‐PCR. With Northern blot analysis, it was detected abundantly in the testis and ovary, but it was barely detectable in 14 other normal human adult organs. Colony formation assay revealed that its augmented expression is associated with promoted cell growth. As these expression profiles and functional features of SCRN1 appeared to be compatible with the characteristics of the hypothesized ideal TAAs, we examined whether SCRN1 protein contains antigenic epitope peptides restricted to HLA‐A*0201. We synthesized the candidate peptides derived from SCRN1, and tried to induce CTLs with each peptide. The CTL clones were successfully induced with a peptide SCRN1‐196 (KMDAEHPEL), and they lyzed not only the peptide‐pulsed targets but also the tumor cells expressing both SCRN1 and HLA‐A*0201 endogenously. These results strongly suggest that SCRN1‐196 is an epitope peptide restricted to HLA‐A*0201. Furthermore, we synthesized an anchor‐modified peptide SCRN1–9 V (KMDAEHPEV), in which leucine at position 9 was substituted for valine to increase the binding affinity to the HLA‐A*0201 molecules. The CTL clones induced by SCRN1–9 V also recognized tumor cells expressing its natural SCRN1 protein endogenously. These results strongly suggest that SCRN1 is a novel TAA and these peptides, both native and modified, may be applicable for cancer vaccines to treat gastric cancer. (Cancer Sci 2006; 97: 411–419)
Genetics of complex respiratory diseases: implications for pathophysiology and pharmacology studies

There has been a huge influx of data on the genetics and genomics of respiratory diseases in the last few years. Powered by large sample sizes from collaborations worldwide, recent genome‐wide association studies have convincingly implicated variants in different regions in the genome for association with complex respiratory traits. These new associations have the potential to offer invaluable insight into the pathophysiology of the normal and diseased respiratory system. The functional mechanisms underlying effects of both identified and novel variants will be the focus of research over the next few years. The identification of these mechanisms will not only increase our understanding of disease but may allow the development of new therapies to alleviate respiratory conditions. The implications of these approaches for studies of asthma and Chronic Obstructive Pulmonary Disease are covered in this review.
Ultrastructure of the embryonic snake skin and putative role of histidine in the differentiation of the shedding complex

The morphogenesis and ultrastructure of the epidermis of snake embryos were studied at progressive stages of development through hatching to determine the time and modality of differentiation of the shedding complex. Scales form as symmetric epidermal bumps that become slanted and eventually very overlapped. During the asymmetrization of the bumps, the basal cells of the forming outer surface of the scale become columnar, as in an epidermal placode, and accumulate glycogen. Small dermal condensations are sometimes seen and probably represent primordia of the axial dense dermis of the growing tip of scales. Deep, dense, and superficial loose dermal regions are formed when the epidermis is bilayered (periderm and basal epidermis) and undifferentiated. Glycogen and lipids decrease from basal cells to differentiating suprabasal cells. On the outer scale surface, beneath the peridermis, a layer containing dense granules and sparse 25–30‐nm thick coarse filaments is formed. The underlying clear layer does not contain keratohyalin‐like granules but has a rich cytoskeleton of intermediate filaments. Small denticles are formed and they interdigitate with the oberhautchen spinulae formed underneath. On the inner scale surface the clear layer contains dense granules, coarse filaments, and does not form denticles with the aspinulated oberhautchen. On the inner side surface the oberhautchen only forms occasional spinulae. The sloughing of the periderm and embryonic epidermis takes place in ovo 5–6 days before hatching. There follow beta‐, mesos‐, and alpha‐layers, not yet mature before hatching. No resting period is present but a new generation is immediately produced so that at 6–10 h posthatching an inner generation and a new shedding complex are forming beneath the outer generation. The first shedding complex differentiates 10–11 days before hatching. In hatchlings 6–10 h old, tritiated histidine is taken up in the epidermis 4 h after injection and is found mainly in the shedding complex, especially in the apposed membranes of the clear layer and oberhautchen cells. This indicates that a histidine‐rich protein is produced in preparation for shedding, as previously seen in lizard epidermis. The second shedding (first posthatching) takes place at 7–9 days posthatching. It is suggested that the shedding complex in lepidosaurian reptiles has evolved after the production of a histidine‐rich protein and of a beta‐keratin layer beneath the former alpha‐layer. J. Morphol. 251:149–168, 2002. © 2002 Wiley‐Liss, Inc.
Autocrine Human Growth Hormone Inhibits Placental Transforming Growth Factor-β Gene Transcription to Prevent Apoptosis and Allow Cell Cycle Progression of Human Mammary Carcinoma Cells*

Multiple cellular effects of human growth hormone (hGH) are mediated by an indirect mechanism requiring transcriptional activation of genes encoding protein effector molecules such as insulin-like growth factor-1. Such protein effector molecules then act directly to mediate the cellular functions of hGH. We report here that autocrine hGH production by mammary carcinoma cells specifically results in the transcriptional repression of the p53-regulated placental transforming growth factor-β (PTGF-β) gene. Transcriptional repression of the PTGF-β gene does not require the p53-binding sites in the PTGF-β promoter, and autocrine hGH also desensitized the response of thePTGF-β promoter to p53 overexpression. Transcriptional repression of the PTGF-β gene is accompanied by consequent decreases in its protein product, Smad-mediated transcription, and its cellular effects that include cell cycle arrest and apoptosis. PTGF-β specifically inhibited the autocrine hGH-stimulated expression of cyclin D1 required for autocrine hGH-stimulated mammary carcinoma cell cycle progression. Thus, one mechanism by which autocrine hGH promotes an increase in mammary carcinoma cell number is by transcriptional repression of protein effector molecules that promote cell cycle arrest and apoptosis. Such transcriptional repression of negative regulatory factors, such as PTGF-β, may also be requisite for direct stimulation of mammary carcinoma cell mitogenesis by hGH.
Ecological and molecular studies on emerging schistosomiasis mansoni in Dhofar Governorate, Sultanate of Oman

The recent detection of some cases of autochtonous schistosomiasis mansoni in Dhofar, Oman, prompted a search for the transmission sites. The five field surveys we conducted from November 2000 to February 2002 provided ecological data on schistosomiasis in Dhofar. Twenty‐eight water bodies situated within 8–160 km from Salalah, the largest city of Dhofar and at altitudes of up to 900 m, were surveyed for freshwater snails. Biomphalaria arabica was found in 15 of them. Three sites (Tibraq, Siginitti and Arazat) had Schistosoma infected snails, the first snails shedding cercariae of this parasite ever collected in Oman. The parasite from Dhofar was analysed by Random Amplified Polymorphic DNA comparisons using 11 primers and 167 polymorphic fragments and had 87–88% similarity with Schistosoma mansoni from Guadeloupe, but only 37–38% similarity with S. rodhaini from Burundi. Thus, it is a strain of S. mansoni. During the November 2000 survey, the prosobranch snail Melanoides tuberculata was associated with B. arabica in 10 of the 13 B. arabica sites. Cercariae from other species of Digenea emerged from five of the B. arabica sites, including the three named above. This paper presents the first finding of S. mansoni in the Dhofar Governorate and represents an initial study of the biology of S. mansoni transmission. This parasite and its cycle need further biological and molecular characterization, and the clarification of its epidemiological status in Dhofar Governorate is an urgent task.
Ductal epithelial proliferations of the breast: a biological continuum? Comparative genomic hybridization and high‐molecular‐weight cytokeratin expression patterns

According to current concepts, benign proliferative breast disease (BPBD) is a direct precursor of breast cancer, in a spectrum ranging from ductal hyperplasia to overtly invasive carcinoma. In this study, comparative genomic hybridization (CGH) was used to screen ductal hyperplasia and other BPBD lesions and ductal carcinoma in situ (DCIS) for common genomic abnormalities, to test the relationship between these hyperplastic and neoplastic lesions. Immunohistochemistry for cytokeratin 5/6 was used as a diagnostic adjunct to distinguish ductal hyperplasia from DCIS. A total of 42 cases of BPBD comprising ductal hyperplasia of the usual type (n=14), papilloma (n=22), tubular adenoma (n=3), and adenosis (n=3), as well as 52 cases of DCIS, were studied. All cases of BPBD consistently displayed the presence of a subpopulation of cytokeratin 5/6‐expressing basal‐type cells within the proliferative lesion, whereas all of the non‐high‐grade and most of the high‐grade DCIS lesions lacked cytokeratin 5/6‐positive cells. Whereas gross genomic alterations, as determined by CGH, were undetectable in BPBD, distinct genetic changes characterized all cases of DCIS, with one exception. These results confirm the usefulness of cytokeratin 5/6 immunohistology in the diagnosis of BPBD and neoplastic breast lesions and support the view that BPBD and DCIS are not closely related entities and that BPBD is not an obligate direct precursor of DCIS. Copyright © 2001 John Wiley & Sons, Ltd.