bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene autoregulation by 3’ UTR-derived bacterial small RNAs
Authors: Hoyos Mona , Huber Michaela , Förstner Konrad U , Papenfort Kai
Published: July 2020

Negative feedback regulation, that is the ability of a gene to repress its own synthesis, is the most abundant regulatory motif known to biology. Frequently reported for transcriptional regulators, negative feedback control relies on binding of a transcription factor to its own promoter. Here, we report a novel mechanism for gene autoregulation in bacteria relying on small regulatory RNA (sRNA) and the major endoribonuclease, RNase E. TIER-seq analysis (transiently-inactivating-an-endoribonuclease-followed-by-RNA-seq) revealed ~25,000 RNase E-dependent cleavage sites inVibrio cholerae, several of which resulted in the accumulation of stable sRNAs. Focusing on two examples, OppZ and CarZ, we discovered that these sRNAs are processed from the 3’ untranslated region (3’ UTR) of theoppABCDFandcarABoperons, respectively, and base-pair with their own transcripts to inhibit translation. For OppZ, this process also triggers Rho-dependent transcription termination. Our data show that sRNAs from 3’ UTRs serve as autoregulatory elements allowing negative feedback control at the post-transcriptional level.
Effects of Record Keeping on the Growth of Small Scale Enterprises in Abeokuta South Local Government Area, Ogun State, Nigeria
Authors: Olajide Muyiwa , Obialo Felix-Kingsley
Published: July 2020

The study seeks to find the effects of recordkeeping on the growth of small scale enterprises (SSEs) in Abeokuta Local Government Area, Ogun State, Nigeria. Survey design was used to purposively select 120 (53 males, 67 females) business owners from a population of 170 registered SSEs in the local government registry. A structured questionnaire with a reliability index of 0.76 (Cronbach Alpha) was used to elicit information from the respondents. The businesses were trading, manufacturing, fashion, telecommunications and agriculture. Data was analysed through descriptive statistics like simple percentages, mean and standard deviation. The results revealed that the highest age range of the respondents was 26- 30 years (26.7%) while there were two lowest age ranges< 25 years and 36-40 years (2.5% each). The businesses were mostly between 1- 5 years (68.3%) old, implying that they were mostly start-ups. 31.7% of the businesses were 6 years and above, meaning that the survival rate of older businesses was low.  Majority of the business owners were into manufacturing (35.8%). Despite SSEs owners having a positive attitude towards record keeping, 59.2% of them kept financial records manually by themselves without any professional help. Data also revealed that stock records influence sales growth. Income and expenditure record positively affect the profitability of small scale enterprises while debtors and creditors’ record enhance operational efficiency of SSEs. Consequently, small scale business owners should learn to keep proper financial records to forestall the collapse of their businesses by engaging professional accountants and by using different accounting software.
Effect of Company Strategies on Organisational Performance in Nigerian Construction Industry
Authors: Abel U. V. Alintah- , Iheama N. B. , Ugochukwu S. C.
Published: July 2020

Changes in the environment such as customers’ preferences and choices has put the companies on toes with each firm fighting for its survival and all is based on strategies choice and their implementation. Thus, Nigerian construction companies have to adopt and apply appropriate strategies to be more competitive in this industry and get success in their businesses. Hence, the aim of this study was to investigate the effect of company strategies on organisational performance in Nigerian construction industry. The conceptual framework was provided to give a guideline on how both independent and dependent variables will interact in other to get the impact of companies’ strategies on performance. Primary data with the aid of a structured questionnaire was used to elicit information from respondents. The data collected were analysed using both descriptive such as percentages and mean and inferential statistics of regression analysis was used to test the hypotheses. The findings revealed that construction companies adopt several company strategies at various levels; however, the strategies are generally applied moderately in the firms. The study deduced that both growth strategies and generic strategies have positive significant impact on performance. The study recommended that policy makers and the management of the construction firms should adopt a mix of the competitive strategies since both have positive impact on performance and there is need for companies to intensify their applications since it will spur performance in the organisation.
Spatial relationship between SH1 and the actin binding site on myosin subfragment‐1 surface
Authors: Yamamoto Keiichi , Sekine Takamitsu , Sutoh Kazuo
Published: July 2002

To examine the spatial relationship between SH1 thiol and actin binding site on subfragment‐1 surface, we studied the interaction with actin of subfragment‐1 whose SH1 was labeled with an iodoacetate derivative of biotin and covered with avidin. Subfragment‐1‐avidin complex bound F‐actin and its Mg2+ ATPase activity was activated by actin. Considering the size and the location of biotin binding site on avidin, our results suggest that SH1 is separated from the actin binding site on subfragment‐1 surface by at least 17–20 Å.
Amino acid composition of α‐ and β‐chains of yeast and wheat germ pyruvate decarboxylase
Authors: Zehender Hartmut , Ullrich Johannes
Published: July 2002

Thus, the recently isolated structural gene for yeast PDC cannot suffice for coding both chains.
The oxidation of exogenous cytochrome c by mitochondria
Authors: Wikström Mårten , Casey Robert
Published: July 2002

Several reports in the past have dealt with the oxidation of cytochrome c added to suspensions of rat liver mitochondria. Yet, it is generally believed that the cytochrome cannot penetrate the outer membrane. Probably it has been assumed that the permeability of the outer membrane to cytochrome c is very low but finite, and that fast oxidation may be observed if time is allowed for sufficient penetration before initiation of electron flow. Here we show that this view is false. The main fraction of rat liver mitochondria, as isolated by conventional procedures, does not catalyse any significant oxidation of added cytochrome c, even after prolonged incubation. The observed appreciable oxidation of added cytochrome c is catalysed by a very small fraction (5–12%) of the mitochondria that apparently has a damaged outer membrane. Consequently, the turnover of cytochrome oxidase is very high in this fraction during oxidation of added cytochrome c. This finding readily explains why Moyle and Mitchell (e.g., FEBS Lett. 88 (1978) 268‐272; 90 (1978) 361‐365) have failed to observe proton translocation by cytochrome oxidase during oxidation of ferrocytochrome c added to rat liver mitochondria, which has been their main reason for rejecting the proton‐pumping function of cytochrome oxidase.
Developmental and regional changes of cholecystokinin mRNA in rat brains
Authors: Hasegawa Makoto , Usui Hiroshi , Araki Kazuaki , Kuwano Ryozo , Takahashi Yasuo
Published: July 2002

Since the nucleotide sequence of cholecystokinin (CCK) cDNA was found in the rat gene, we applied cDNA to quantitate the CCK mRNA. The size of the mRNA for a CCK precursor was 850 nucleotides in length using brain cytoplasmic RNA. There were no bands except CCK mRNA by Northern blot analysis. We also examined the developmental changes and regional distribution of CCK mRNA in rat brains by dot‐blot and gel‐blot hybridization using CCK cDNA as a probe. CCK mRNA was barely detectable in the fetal brain, but started to increase postnatally and attained the plateau level after 20–30 days. Further, the level of CCK mRNA was highest in the frontal cortex, followed by those of the hippocampus and striatum. The cerebellum contained only negligible CCK mRNA. These results are in agreement with those of CCK concentration in the corresponding brain areas and suggest a transcriptional control of CCK concentration.
Time‐resolved measurements of fluorescence from reaction centres of Rhodopseudomonas sphaeroides R26.1
Authors: Hörber J.K.H. , Göbel W. , Ogrodnik A. , Michel-Beyerle M.E. , Cogdell R.J.
Published: July 2002

The fluorescence decay pattern of the emission from the ‘special pair’ in reaction centres from Rhodopseudomonas sphaeroides R26.1 was recorded with a time resolution of 1 ns. The decay kinetics were monitored in photochemically ‘open’ reaction centres and in reaction centres ‘closed’ either by chemical reduction of the ubiquinone or by prior removal of the ubiquinone. As previously noted with reaction centres from Rhodopseudomonas viridis three fluorescence decay phases have been resolved. The origin of these phases is described in terms of a model which assumes that some of the initial charge separation in the reaction centre occurs in the ‘M’ branch as well as in the ‘L’ branch and that putting a negative charge on the quinone electrostatically inhibits the forward rate of the charge separation.
The human osteosarcoma cell line U‐2 OS expresses a 3.8 kilobase mRNA which codes for the sequence of the PDGF‐B chain
Authors: Weich H.A. , Sebald W. , Schairer H.-U. , Hoppe J.
Published: July 2002

A cDNA clone of about 2500 base pairs was prepared from the human osteosarcoma cell line U‐2 OS by hybridizing with a v‐sis probe. Sequence analysis showed that this cDNA contains the coding region for the PDGF‐B chain. Here we report that the mitogen secreted by these osteosarcoma cells contains the PDGF‐B chain and is probably a homodimer of two B‐chains.
Finger proteins and DNA‐specific recognition: Distinct patterns of conserved amino acids suggest different evolutionary modes
Authors: Payre François , Vincent Alain
Published: July 2002

Finger proteins, the first example of which was Xenopus TFIIIA, share Zn2+ finger‐like folded domains capable of binding to nucleic acids. A large number of this type of protein have been characterised from diverse organisms, indicating a wide evolutionary spread of the DNA‐binding fingers. At least two classes of finger proteins may be distinguished. Class I proteins contain variable numbers of the tandemly repeating TFIIIA‐like finger motif, (Y/F‐X‐C‐X2–4‐C‐X3‐F‐X5‐L‐X2‐H‐X3‐H). Class II finger proteins display a single (C‐X2‐C‐X13‐C‐X2‐C) motif and a facultative second putative finger. The relation between the structure of finger proteins and their recognised DNA sequences is discussed.
Expression of phosphoglycerate mutase mRNA in differentiating rat satellite cell cultures
Authors: Castellà-Escolà J. , Ureña J. , Alterio J. , Carreras J. , Martelly I. , Climent F.
Published: July 2002

Poly (A)+ mRNA was isolated from rat satellite cell cultures and analyzed by Northern blot analyses for mRNA content of phosphoglycerate mutase (PGAM) isozymes. In non‐differentiating satellite cells only PGAM‐B mRNA was detected, but when cells were differentiated into myotubes, which undergo spontaneous contraction, mRNA for PGAM‐M muscle‐specific isozyme was also detected. This finding is in perfect concordance with the transition of PGAM isozymes encountered in the same cell cultures, and strongly supports a transcriptional control of PGAM expression throughout myogenesis independently of nerve influence.
Localization of aldolase C mRNA in brain cells
Authors: Popovici Théodora , Berwald-Netter Yoheved , Vibert Magdeleine , Kahn Axel , Skala Henriette
Published: July 2002

The expression of aldolase C and aldolase A mRNA was assessed by Northern blot hybridization using RNAs purified from cultured rat and mouse brain neurons and astroglial cells. Neurons were found to contain about 4‐fold more aldolase C mRNA and about twice as much aldolase A mRNA than astroglia. Analysis of the cellular localization of aldolase C mRNA by in situ hybridization to brain slices showed a predominantly neuronal labeling with an irregular distribution. A strong signal was observed in Purkinje cell somata and a weaker signal in subpopulations of neurons in cerebral cortex, striatum, hippocampus, hypothalamic nuclei and primary olfactory cortex.
Variability of polyadenylation sites in mRNAs from human fetal liver
Authors: Dmitrenko Vladimir V. , Kavsan Vadim M.
Published: July 2002

cDNA libraries of human fetal liver were constructed in pBR322 and λgt10 vectors. The libraries were screened for liver‐specific clones by differential hybridization. This procedure revealed 25 and 32 liver‐specific clones in plasmid and phage libraries, respectively. The majority of these clones were represented with serum albumin, fetal Gγ‐globin and Aγ‐globin cDNA inserts. Three types of 3′‐non‐coding region were found in 5 sequenced albumin cDNAs. In one type mRNA the distance between the AATAAA signal and polyadenylation site was 15 nucleotides, in 2 other types this distance was 10 and 6 nucleotides. The polyadenylation site in the Gγ‐globin cDNA was located 2 nucleotides further from AATAAA signal, while in the Aγ‐globin cDNA it was 2 nucleotides closer to the signal as compared with the results published previously.
Development and characterization of a protein kinase C β‐isozyme‐deficient T‐cell line
Authors: Kelleher Dermot , Long Aideen
Published: July 2002

In the human T‐cell lymphoma line, HuT 78, proliferation and phorbol ester‐induced growth arrest and differentiation were inhibited by the protein kinase C (PKC) inhibitor, staurosporine. By contrast, an alternative PKC inhibitor, H‐7, inhibited proliferation but not phorbol ester‐induced growth arrest. The cell line was found to contain both α and β isoforms of PKC by Western blot techniques. A cell line, K‐4, was cloned from HuT 78 in the presence of H‐7 and this clone was found to be positive for PKC‐α only. PKC‐β did not return on cultivation in the absence of H‐7. Proliferation of K‐4 was insensitive to inhibition with both H‐7 and staurosporine. However, phorbol ester‐induced growth arrest remained staurosporine sensitive. Phorbol‐stimulated IL‐2 secretion was minimal in the PKC‐β‐deficient cell line. These data suggest that PKC‐β may be a regulatory enzyme for proliferation and stimulated interleukin‐2‐secretion in HuT 78 cells. Heterogeneity of responses to PKC activation may reflect the use of different isozymes in different intracellular pathways. The K‐4 cell line should provide a useful tool in the dissection of involvement of PKC isozymes in cellular function.
Mechanism and site of action of a ribosome‐inactivating protein type 1 from Dianthus barbatus which inactivates Escherichia coli ribosomes
Authors: Prestle Jürgen , Hornung Ellen , Schönfelder Max , Mundry Karl-Wolfgang
Published: July 2002

A single chain ribosome‐inactivating protein with RNA N‐glycosidase activity, here named Dianthin 29, was isolated from leaves of Dianthus barbatus L. Incubation of intact Escherichia coli ribosomes with Dianthin 29 and subsequent aniline treatment of the isolated rRNA releases a rRNA fragment of 243 nucleotides from 23 S rRNA. Nucleotide sequence studies showed that the site of N‐glycosidic bond cleavage is at A‐2660 within the universally conserved sequence 5′‐AGUACGGAGGA‐3′ near the 3′‐end of 23/28 S rRNAs. To our knowledge, Dianthin 29 is the first ribosome‐inactivating protein which is shown to inactivate intact prokaryotic ribosomes in the same manner as eukaryotic ribosomes.
Elucidation of a conserved RNA stem‐loop structure in the packaging signal of human immunodeficiency virus type 1
Authors: Hayashi Takuma , Ueno Yoshio , Okamoto Takashi
Published: July 2002

A region of human immunodeficiency virus type 1 (HIV‐1) genomic RNA known to interact with the viral nucleocapsid protein is one of the crucial components for retroviral genomic RNA packaging. We have investigated the secondary structure for this RNA packaging signal of HIV‐1 using RNA mapping techniques and extensive computer analyses. Our results suggest that the RNA sequence containing the packaging signal conforms to a stable stem‐loop structure and that a portion of this structure is conserved among twenty independent HIV‐1 isolates. The heterogeneity of the RNA packaging sequence was not correlated with the amino acid sequence variability of the viral nucleocapsid protein. These findings have critical implication in understanding the viral maturation process.
Modulation of functional activities of the neurotoxin from black widow spider venom
Authors: Grishin E.V. , Himmelreich N.H. , Pluzhnikov K.A. , Pozdnyakova N.G. , Storchak L.G. , Volkova T.M. , Woll P.G.
Published: July 2002

We have studied the action of an α‐latrotoxin (α‐LTX) complex of two polypeptides (LTX 130 kDa and low molecular weight protein (LMWP) 8 kDa) and the action of a venom fraction containing LTX with excess LMWP on calcium influx into synaptosomes and PC 12 cells as well as on [14C[GABA release from synaptosomes. Both preparations considerably activate calcium influx and stimulate [14C]GABA release from synaptosomes. Preincubation of both preparations with antibodies against a 14 amino acid residue C‐terminal peptide of LMWP differentially modulates these effects. Antibodies inhibit induced calcium influx and enhance induced GABA release.
Protein translocation: Common themes from bacteria to man
Authors: Jungnickel Berit , Rapoport Tom A. , Hartmann Enno
Published: July 2002

Protein transport across the endoplasmic reticulum membrane in eukaryotes and across the cytoplasmic membrane in bacteria have turned out to be highly related. The core component of the translocation apparatus is the Sec61/SecYp complex; at least two of its subunits are conserved in evolution. The Sec61/SecYp complex is involved in both co‐ and post‐translational transport pathways. The two modes require probably distinct additional components.
Insulin‐like growth factors counteract the effect of interleukin 1β on type II phospholipase A2 expression and arachidonic acid release by rabbit articular chondrocytes
Authors: Berenbaum F. , Thomas G. , Poiraudeau S. , Béréziat G. , Corvol M.T. , Masliah J.
Published: July 2002

Interleukin 1β was found to stimulate arachidonic acid release, and the synthesis and secretion of type II phospholipase A2 by rabbit articular chondrocytes in vitro. Interleukin 1β had no effect on the level of cytosolic phospholipase A2 mRNA. Insulin‐like growth factors, which help stabilize the cartilage matrix, reduced the effect of interleukin 1β on type II phospholipase A2 activity and mRNA level, and decreased the Interleukin 1β‐stimulated arachidonic acid release to the basal values. This suggests that type II phospholipase A2 plays a key role in arachidonic acid release from rabbit articular chondrocytes and that insulin‐like growth factors counteract the effect of interleukin 1β. They may therefore be considered as potential antiinflammatory agents.
Redox control of gene expression involving iron‐sulfur proteins. Change of oxidation‐state or assembly/disassembly of Fe‐S clusters?
Authors: Beinert Helmut , Kiley Patricia
Published: July 2002

Attention is drawn to a mechanism of redox control of gene expression involving Fe‐S proteins which depends on the disassembly and reassembly of Fe‐S clusters rather than a change in oxidation state. Iron Regulatory Protein (IRP)/aconitase and FNR are discussed as examples for such a mechanism.
Aspirin induces apoptosis through mitochondrial cytochrome c release
Authors: Piqué Maria , Barragán Montserrat , Dalmau Mireia , Bellosillo Beatriz , Pons Gabriel , Gil Joan
Published: July 2002

Aspirin and other non‐steroidal anti‐inflammatory drugs induce apoptosis in many cell types. Although the involvement of caspases has been demonstrated, the mechanism leading to caspase activation remains unknown. We have studied the role of the mitochondrial pathway in aspirin‐induced apoptosis. The apoptotic effect of aspirin was analyzed in different cell lines (Jurkat, MOLT‐4, Raji and HL‐60) showing induction of mitochondrial cytochrome c release and caspases 9, 3 and 8 processing. Furthermore, early aspirin‐induced cytochrome c release was not affected by the caspase inhibitor Z‐VAD·fmk and preceded loss of mitochondrial membrane potential. Therefore, aspirin‐induced apoptosis involves caspase activation through cytochrome c release.
Inhibition of electron transport at the cytochrome b6f complex protects photosystem II from photoinhibition
Authors: Krieger-Liszkay A. , Kienzler K. , Johnson G.N.
Published: July 2002

Photoinhibition of photosystem II (PS II) activity was studied in thylakoid membranes illuminated in the presence of the inhibitor of the cytochrome b6f complex 2′iodo‐6‐isopropyl‐3‐methyl‐2′,4,4′‐trinitrodiphenylether (DNP‐INT). DNP‐INT was found to decrease photoinhibition. In the absence of DNP‐INT, anaerobosis, superoxide dismutase and catalase protected against photoinhibition. No effect of these treatments was observed in the presence of DNP‐INT. These data demonstrate that photoinhibition under these conditions is caused by reactive oxygen species which are formed most probably by the reduction of oxygen at photosystem I. The results are discussed in terms of the importance of photosynthetic control in protection against photoinhibition in vivo.
Failure to activate interleukin 1β‐converting enzyme‐like proteases and to cleave retinoblastoma protein in drug‐resistant cells
Authors: An Bing , Jin Jia-Rui , Lin Peggy , Dou Q.Ping
Published: July 2002

We previously found that retinoblastoma (RB) is cleaved at the initiation of apoptotic execution. Here we report that when an HL‐60 cell line resistant to cytosine arabinoside (Ara‐C) was exposed to this anticancer drug, neither RB cleavage nor apoptosis was detected. Consistent with that, processing of interleukin 1β‐converting enzyme (ICE) and CPP32 (an ICE‐like protease) was also prevented in these cells. In contrast, treatment of the HL‐60‐Ara‐C‐resistant cells with etoposide induced all of these apoptotic events. Furthermore, the etoposide‐induced RB cleavage was inhibited by a specific tetrapeptide ICE‐like inhibitor. Our results demonstrate that activation of the RB cleavage enzyme, an ICE‐like protease, is required for overcoming drug resistance.
Positively charged lysine at the N‐terminus of the signal peptide of the Escherichia coli alkaline phosphatase provides the secretion efficiency and is involved in the interaction with anionic phospholipids
Authors: Nesmeyanova Marina A , Karamyshev Andrew L , Karamysheva Zemphyra N , Kalinin Andrey E , Ksenzenko Vladimir N , Kajava Andrey V
Published: July 2002

© 1997 Federation of European Biochemical Societies.
Ubiquitination of Na,K‐ATPase α1 and α2 subunits
Authors: Coppi Maddalena Virginia , Guidotti Guido
Published: July 2002

Na,K‐ATPase, an essential transporter of mammalian cells, is an oligomeric transmembrane protein composed of two subunits, α and β, of which there are several isoforms. In this study, we demonstrate that the α1 and α2 isoforms of the Na,K‐ATPase α subunit are modified by the covalent attachment of ubiquitin polymers in COS‐7 cells. We propose that polyubiquitination of the Na,K‐ATPase α subunit may play a role in regulating its degradation.
Immunological identification of the alternative oxidase of Acanthamoeba castellanii mitochondria
Authors: Jarmuszkiewicz Wieslawa , Wagner Anneke M , Wagner Marijke J , Hryniewiecka Lilla
Published: July 2002

Mitochondria of the protozoa Acanthamoeba castellanii possess a cyanide‐insensitive oxidase cross‐reacting with monoclonal antibodies raised against the plant alternative oxidase. Immunoblotting revealed three monomeric forms (38, 35, and 32 kDa) and very low amounts of a single 65 kDa dimeric form. Cross‐linking studies suggest that while in plants the alternative oxidase occurs as a dimer, in amoeba it functions as a monomer. Immunologically detectable protein levels change with the age of amoeba cell culture. Increased amounts of the 35 kDa protein are accompanied by an increase in the activity of cyanide‐resistant respiration.
Periportal localization of glucagon receptor mRNA in rat liver and regulation of its expression by glucose and oxygen in hepatocyte cultures
Authors: Krones Anja , Kietzmann Thomas , Jungermann Kurt
Published: July 2002

Glucagon is the major hormone activating glycogenolysis and gluconeogenesis both localized in the periportal, more aerobic zone of the liver. Accordingly, the glucagon receptor (GcgR) mRNA was found to be predominantly expressed in this area. In hepatocyte cultures high glucose concentrations as reached after a meal induced GcgR mRNA under arterial but not venous pO2. The induction by glucose was partially antagonized by insulin and unaffected by glucagon. The modulation by O2 of the glucose‐dependent induction would contribute to the zonated expression of GcgR mRNA.
δ‐Atracotoxins from Australian funnel‐web spiders compete with scorpion α‐toxin binding on both rat brain and insect sodium channels
Authors: Little Michelle J , Wilson Harry , Zappia Cathy , Cestèle Sandrine , Tyler Margaret I , Martin-Eauclaire Marie-France , Gordon Dalia , Nicholson Graham M
Published: July 2002

δ‐Atracotoxins are novel peptide toxins from the venom of Australian funnel‐web spiders that slow sodium current inactivation in a similar manner to scorpion α‐toxins. To analyse their interaction with known sodium channel neurotoxin receptor sites we determined their effect on scorpion toxin, batrachotoxin and saxitoxin binding. Nanomolar concentrations of δ‐atracotoxin‐Hv1 and δ‐atracotoxin‐Ar1 completely inhibited the binding of the scorpion α‐toxin AaH II to rat brain synaptosomes as well as the binding of LqhαIT, a scorpion α‐toxin highly active on insects, to cockroach neuronal membranes. Moreover, δ‐atracotoxin‐Hv1 cooperatively enhanced batrachotoxin binding to rat brain synaptosomes in an analogous fashion to scorpion α‐toxins. Thus the δ‐atracotoxins represent a new class of toxins which bind to both mammalian and insect sodium channels at sites similar to, or partially overlapping with, the receptor binding sites of scorpion α‐toxins.
Spontaneous rearrangements in RNA sequences
Authors: Chetverina Helena V , Demidenko Alexander A , Ugarov Victor I , Chetverin Alexander B
Published: July 2002

The ability of RNAs to spontaneously rearrange their sequences under physiological conditions is demonstrated using the molecular colony technique, which allows single RNA molecules to be detected provided that they are amplifiable by the replicase of bacteriophage Qβ. The rearrangements are Mg2+‐dependent, sequence‐non‐specific, and occur both in trans and in cis at a rate of 10−9 h−1 per site. The results suggest that the mechanism of spontaneous RNA rearrangements differs from the transesterification reactions earlier observed in the presence of Qβ replicase, and have a number of biologically important implications.
GnRH agonist decreases endothelial nitric oxide synthase (eNOS) expression in leiomyoma
Authors: Gokdeniz R. , Ozen S. , Mizrak B. , Bazoglu N.
Published: July 2002

Objective: To define the effect of GnRH agonist (GnRHa) treatment on endothelial nitric oxide synthase (eNOS) expression in leiomyoma. As eNOS expression is more pronounced in leiomyoma compared to parental myometrium, we hypothesized that the mechanism(s) of tumor shrinkage by GnRHa may be due to decreased nitric oxide (NO) production in leiomyoma. Methods: Eleven patients with leiomyoma were operated for myoma enucleation by laparatomy. Six of them were treated with GnRHa every 28 days, three times before the operation. The remaining five patients who had no treatment prior to operation formed the control group. Blood was drawn from the patients before treatment and on the day of operation for the assay of serum estradiol (E2). Immunohistochemical localization of eNOS expression in leiomyoma and myometrium in treated patients, and in leiomyoma in the control group, was performed using monoclonal antibodies specific to eNOS. Results: All treated subjects showed a significant reduction of fibroid volume at the end of therapy. eNOS‐positive cells were localized primarily within the vascular endothelium and smooth muscle cells, but had weak expression in fibroid and myometrial muscle cells in the treated group. The immunoreactivity was similar for both the leiomyoma and myometrium (P>0.05). In contrast to this, the control group had shown strong expression in leiomyoma muscle cells (P<0.005) in addition to the vascular endothelium and smooth muscle cells. Conclusion: GnRHa‐induced tumor shrinkage should be due to diminished eNOS expression, most probably by lowering estrogen secretion.
Cytokine regulation of cartilage‐derived retinoic acid‐sensitive protein (CD‐RAP) in primary articular chondrocytes: suppression by IL‐1, bfGF, TGFβ and stimulation by IGF‐1
Authors: Kondo Seiji , Cha Steven H. , Xie Wei‐Fen , Sandell Linda J.
Published: July 2002

Cartilage‐derived retinoic acid‐sensitive protein (CD‐RAP) is a secreted protein identified in our laboratory by RT‐PCR and differential display [U.H. Dietz, L.J. Sandell. Cloning of a retinoic acid‐sensitive mDNA expressed in cartilage and during chondrogenesis. J. Biol. Chem. 271 (1996) 3311–3316]. It is synthesized by chondrocytes throughout development and down‐regulated by retinoic acid in coordination with type II collagen gene expression. To further explore the regulation CD‐RAP in primary articular chondrocytes, we examined effects of selected cytokines on CD‐RAP gene expression compared to their effects on type II collagen expression. Northern blot analysis showed that expression of CD‐RAP mRNA was suppressed by bFGF, IL‐1β and retinoic acid in coordination with type II collagen mRNA. TGF‐β decreased CD‐RAP expression while increasing type II collagen mRNA whereas both mRNAs were up‐regulated by IGF‐1. In chondrocytes dedifferentiated with retinoic acid, IGF‐1 induced re‐expression of both CD‐RAP and type II collagen mRNAs. The mechanism of stimulation of CD‐RAP by IGF‐1 was further investigated. An mRNA stability assay revealed that IGF‐1 had no effect on CD‐RAP or type II collagen mRNA half life, suggesting that the enhancement by IGF‐1 is due to increased gene transcription. To study the transcriptional mechanism, we used the 5′‐flanking region of the CD‐RAP gene fused to a promoter‐less reporter plasmid encoding luciferase. Deletion analysis of the CD‐RAP promoter indicated that an IGF‐1‐responsive element is present between nucleotides –475 and –458. These data indicate that CD‐RAP expression can be regulated by cytokines known to influence chondrocyte metabolism and that IGF‐1 up‐regulates CD‐RAP gene expression through a transcriptional mechanism. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Is Ukraine a Political Community?1
Authors: Zimmerman William
Published: July 2002

The effects of divergent historical experiences, of differential exposure to the world outside the former Soviet Union, and of divergent industrial structure–all point in the direction of enormous attitudinal and evaluative cleavages across the regions of Ukraine. When we compare regional differences in perspectives on the political economy in Ukraine and views about whether Russia and Ukraine should be separate states, these differences are readily discernible. By extending the scope of items examined and by making explicit comparisons between data from Ukrainian and Russian samples, however, we achieve a somewhat more optimistic view about the prospects for community building in Ukraine. The relatively consensual assessment of citizenship conditions and the wide range of foreign policy matters about which dispositions of Ukrainians are separable from those of persons from regions reported in this paper provide some evidence of an emerging Ukranian political community.
Simple and reliable method to simultaneously determine urinary 1- and 2-naphthol using in situ derivatization and gas chromatography-mass spectrometry for biological monitoring of naphthalene exposure in occupational health practice
Authors: Takeuchi Akito , Nakamura Sadao , Namera Akira , Kondo Tomoaki , Onuki Hiroyuki , Yamamoto Shinobu , Okamura Shingo , Nishinoiri Osamu , Endo Yoko , Miyauchi Hiroyuki , Endo Ginji
Published: July 2020

Objectives

The aim of this study was to develop and validate a simple and reliable gas chromatography-mass spectrometry (GC-MS) method to simultaneously determine urinary 1-naphthol (1-NAP) and 2-naphthol (2-NAP) for biological monitoring of occupational exposure to naphthalene.

Methods

NAPs were derivatized in situ with acetic anhydride after enzymatic hydrolysis, extracted with n-hexane, and analyzed using GC-MS. Validation of the proposed method was conducted in accordance with US Food and Drug Administration guidance. A final validation was performed by analyzing a ClinChek®-Control for phenolic compounds.

Results

The linearity of calibration curves was indicated by a high correlation coefficient (>0.999) in the concentration range 1-100 μg/L for each NAP. The limits of detection and quantification for each NAP were 0.30 and 1.00 μg/L, respectively. The recovery was 90.8%-98.1%. The intraday and interday accuracies, expressed as the deviation from the nominal value, were 92.2%-99.9% and 93.4%-99.9%, respectively. The intraday and interday precision, expressed as the relative standard deviation, was 0.3%-3.9% and 0.4%-4.1%, respectively. The ClinChek® values obtained using our method were sufficiently accurate.

Conclusions

The proposed method is simple, reliable, and appropriate for routine analyses, and is useful for biological monitoring of naphthalene exposure in occupational health practice.
Potential of Graphene–Polymer Composites for Ligament and Tendon Repair: A Review
Authors: Peixoto Tânia , Paiva Maria Conceição , Marques António T. , Lopes Maria A.
Published: July 2020

Tendon/ligament injuries are debilitating conditions that affect the life quality of a great percentage of the adult population. Several challenges still have to be addressed regarding the repair of these tissues, as current treatments show limited success. The use of biocompatible and biodegradable polymeric scaffolds potentially helps accomplish a complete and long‐term functional repair but, unfortunately, these materials lack adequate mechanical properties to be used in such demanding applications. Graphene is a subject of interest for tissue‐repair applications due to its electrical conductivity and mechanical properties. If incorporated adequately, it may significantly improve the physical properties of the composite, even at small loadings. Furthermore, graphene presents a biocompatible surface that may enhance cell adhesion, proliferation and differentiation and demonstrates promising outcomes in several in vitro and in vivo biological applications. Therefore, herein, the potential of graphene materials for the reinforcement of biodegradable polymers of interest for tendon/ligament repair is explored. The effect of graphene on relevant features such as mechanical properties, biodegradability, and biocompatibility is revised, to understand the feasibility of these composites to fulfill the requirements associated with these tissues and conclude how their applicability is extended to this field.
Inline Drift Detection Using Monitoring Systems and Machine Learning in Selective Laser Melting
Authors: Yadav Pinku , Singh Vibhutesh Kumar , Joffre Thomas , Rigo Olivier , Arvieu Corinne , Le Guen Emilie , Lacoste Eric
Published: July 2020

Direct metal laser sintering, an additive manufacturing technique, has a huge growing demand in industries like aerospace, biomedical, and tooling sector due to its capability to manufacture complex parts with ease. Despite many technological advancements, the reliability and repeatability of the process are still an issue. Therefore, there is a demand for inline automatic fault detection and postprocessing tools to analyze the acquired in situ monitoring data aiming to provide better‐quality assurance to the user. Herein, the treatment of the data obtained using the EOSTATE optical tomography monitoring system is focused. A balanced dataset is obtained with the help of computer tomography of the certified part (Stainless Steel CX cylindrical samples), through which a feature matrix is prepared, and the layers of the part are classified either having “Drift” or “No‐drift.” The model is trained with the feature matrix and tested on benchmark parts (Maraging Steel) and on an industrial part (knuckle, automotive part) manufactured in AlSi10Mg. The proposed semisupervised approach shows promising results for presented case studies. Thus, the semisupervised machine learning approach, if adopted, could prove to be a cost effective and fast approach to postprocess the in situ monitoring data with much ease.
Surgical management of adenocarcinoma of the transverse colon: What should be the extent of resection?
Authors: Roy Manas K. , Pipara Amrit , Kumar Ashok
Published: July 2020

Transverse colon, owing its origin to midgut and hindgut and harbouring a flexure at both ends, continues to pose a surgical challenge. When compared to the rest of the colon, transverse colon adenocarcinoma is relatively uncommon. These cancers usually present late and lie in close proximity to the stomach, omentum, and pancreas. Adequate lymphadenectomy entails dissection around and ligation of the middle colic vessels. Hence, resectional surgery for transverse colon carcinoma is considered difficult. This is more so because of the variation of arterial and venous anatomy. From this perspective, the surgeon is tempted to perform a more radical operation like extended right or left hemicolectomy to secure an adequate lymphadenectomy. Such a cancer has also been dealt with a more limited transverse colectomy with colo‐colic anastomosis. For all these reasons, patients with transverse colon adenocarcinoma were excluded from randomised trials which compared laparoscopic resection with traditional open operation. Surgical literature is yet to establish a definite operation for transverse colon cancer and the exact procedure is often dictated by surgeon's preference. This is primarily because this is an uncommon cancer. The rapid adoption of laparoscopic operation favoured extended colectomy as transverse colectomy can be difficult by minimally invasive technique. However, in the recent past, cohort studies and meta‐analyses have shown equivalent oncological outcome between transverse colectomy and extended colectomy. It is time to resurrect transverse colectomy and consider it equivalent to its radical counterpart for cancers around the mid‐transverse colon.
Low‐dose and long‐term azithromycin significantly decreases Staphylococcus aureus in the microbiome of refractory CRS patients
Authors: Renteria Axel E. , Maniakas Anastasios , Mfuna Leandra Endam , Asmar Marc‐Henri , Gonzalez Emmanuel , Desrosiers Martin
Published: July 2020

Background

The sinonasal microbiome is believed to play an important role in the pathophysiology of refractory chronic rhinosinusitis (CRS). We evaluated changes in the microbiome following a 4‐month course of low‐dose azithromycin. Assessing microbiome alterations following such a treatment may help identify underlying mechanisms of this drug.

Methods

A total of 48 adults with refractory CRS were enrolled in a double‐blind, randomized, placebo‐controlled trial. Patients were randomized to 250 mg of azithromycin or placebo 3 times weekly for 4 months. During this time, daily budesonide saline irrigations were continued. Sinonasal swabs were collected by endoscopically‐assisted method prior to treatment initiation and at the end of it, and sent for 16S ribosomal RNA gene sequencing. High‐resolution ANCHOR pipeline was used to infer and annotate putative species. The 2 patient groups were compared using DESeq2 differential abundance analysis.

Results

From initiation to the end of azithromycin treatment, patients showed a significant difference in beta diversity analysis (p = 0.0004) along with a significant decrease in 71 different operational taxonomic units (OTUs) of Staphylococcus aureus (false discovery rate [FDR] < 0.05) obtained from the differential abundance analysis. This was not observed in placebo‐treated patients. By the end of treatments, azithromycin‐treated patients had a significant decrease in 29 different OTUs of S. aureus (FDR < 0.05) when compared to placebo.

Conclusion

A 4‐month course of 250 mg of azithromycin 3 times weekly in patients with refractory CRS significantly decreases S. aureus abundance in the sinonasal microbiome. Considering the pathogenic role of S. aureus in the refractory CRS population, azithromycin may constitute an additional therapeutic option to help control this disease.
Anillin: The First Proofreading‐like Scaffold?
Authors: Morris Richard G. , Husain Kabir B. , Budnar Srikanth , Yap Alpha S.
Published: July 2020

Scaffolds are fundamental to many cellular signaling pathways. In this essay, a novel class of scaffolds are proposed, whose action bears striking resemblance to kinetic proofreading. Commonly, scaffold proteins are thought to work as tethers, bringing different components of a pathway together to improve the likelihood of their interaction. However, recent studies show that the cytoskeletal scaffold, anillin, supports contractile signaling by a novel, non‐tethering mechanism that controls the membrane dissociation kinetics of RhoA. More generally, such proof‐reading‐like scaffolds are distinguished from tethers by a rare type of cooperativity, manifest as a super‐linear relationship between scaffold concentration and signaling efficiency. The evidence for this hypothesis is reviewed, its conceptual ramifications are considered, and research questions for the future are discussed.
The history of the term pudendum: Opening the discussion on anatomical sex inequality
Authors: Draper Allison
Published: July 2020

The anatomical terminology for the female external genitalia, “pudendum,” was removed from the second edition of the Terminologia Anatomica (2019) in response to opposition of the Latin root of the word (pudēre meaning “to be ashamed”). This recent revision provides an opportunity to discuss sex inequality within the history of anatomy. This viewpoint article compares the evolution of modern anatomical terminology toward clarity and precision to the stagnant non‐descriptive naming of the “pudendum” to illuminate a long timeline of the societal misperception of women. Claudius Galen (129–216 BC) used the Greek αιδοίον/aidoion (from αἰδώς/aidos meaning shame, respect, or modesty) to describe both the male and female external genitalia, as he believed that men and women were isomorphic, the difference lying only in the positioning of the reproductive organs. Galen, however, was not always impartial in his comparisons, repeatedly describing the female as inferior to the male. Andreas Vesalius (1543), whose illustrations greatly influenced the study of anatomy, later drew the female genitalia as Galen described them, as internal equivalents of male genitalia, codifying female shame within anatomical terminology. While renaming “pudendum” is a noble step in support of women, changing one word will not undo generations of implicit bias and institutional oppression. We can, however, work to create culturally and psychosocially competent future physicians through the integrative study of sex and gender issues and anatomy. Through an understanding of historical context, physicians can refocus their actions on providing care in a way that leaves the patient feeling proud, not ashamed.
Wide distribution of central myelin segment along the facial nerve might explain hemifacial spasm with distal nerve compression
Authors: Nomura Kei , Ryu Hiroshi , Ohno Koji , Sato Kohji
Published: July 2020

Introduction

Many researchers have assumed that neurovascular compression of the facial nerve at the site covered by central myelin sheath causes hemifacial spasm. However, some cases do not correspond to this hypothesis. The aim of this study was to clarify the myelin histology in the facial nerve.

Materials and Methods

Histological analyses were conducted on 134 facial nerves from 67 cadavers. Three dimensions were measured in these sections: the length from the upper border of the medullopontine sulcus to the boundary between the central and peripheral myelin sheath along the anterior side; the length from the detachment point of the brain stem to the boundary along the posterior side; and the length of the transitional zone (TZ), known as the Obersteiner–Redlich zone.

Results

Of the 134 facial nerves, 41 were available for study. The length of the central myelin segment ranged from 4.62 to 12.6 mm (mean 8.06 mm; median 7.98 mm) along the anterior side and from 0.00 to 4.58 mm (mean 1.68 mm; median 1.42 mm) along the posterior side of the facial nerve, and the length of the TZ ranged from 0.00 to 2.76 mm (mean 1.51 mm; median 1.42 mm).

Conclusions

In this study, the length of the central myelin segment in the facial nerve was found to be longer than that previously reported.
Unconventional Biocatalytic Approaches to the Synthesis of Chiral Sulfoxides
Authors: Anselmi Silvia , Aggarwal Nandini , Moody Thomas S. , Castagnolo Daniele
Published: July 2020

Sulfoxides are a class of organic compounds that find wide application in medicinal and organic chemistry. Several biocatalytic approaches have been developed to synthesise enantioenriched sulfoxides, mainly by exploiting oxidative enzymes. Recently, the use of reductive enzymes such as Msr and Dms has emerged as a new, alternative method to obtain enantiopure sulfoxides from racemic mixtures. In parallel, novel oxidative approaches, employing nonclassical solvents such as ionic liquids (ILs) and deep eutectic solvents (DESs), have been developed as greener and more sustainable biocatalytic synthetic pathways. This minireview aims highlights the recent advances made in the biocatalytic synthesis of enantioenriched sulfoxides by employing such unconventional approaches.
Codeployment of a percutaneous edge‐to‐edge mitral valve repair device and a ventriculoseptal defect occluder device to address complex mitral regurgitation with leaflet perforation
Authors: Addis Dylan R. , Law Mark , von Mering Gregory , Ahmed Mustafa
Published: July 2020

An 80‐year‐old male with severe, complex mitral regurgitation (MR) after recent transcatheter aortic valve replacement presented in heart failure for percutaneous mitral valve repair and possible tricuspid valve repair. Transesopheageal echocardiography (TEE) demonstrated mixed Carpentier Types 1 and 2 components with annular dilation, two leaflet perforations, and excessive leaflet motion (P2 flail). There were three distinct MR jets appreciated reflecting a central coaptation defect and two posterior mitral valve leaflet perforations emanating from a cystic dilatation. Under TEE guidance transseptal puncture and percutaneous edge‐to‐edge mitral valve repair was performed with a MitraClip XTR device (Abbott, IL). A 10 mm Amplatzer Muscular VSD Occluder (Abbott, Abbott Park, IL) was deployed to close one of the perforations on the posterior leaflet with a significant reduction in MR severity. Attempts at crossing the remaining defect were unsuccessful and the procedure was concluded. The patient recovered uneventfully and transthoracic echocardiography on postoperative day (POD) 1 and again on POD 34 demonstrated normal systolic dominance on pulmonary venous Doppler interrogation, mild to moderate MR, and a mean transvalvular gradient of 5 mmHg. Both devices appeared firmly attached and stable. This is the first documented use of a VSD occluder device in this clinical scenario. Management of complex MR with an approach combining edge‐to‐edge repair for a central coaptation defect and leaflet flail with codeployment of a VSD occluder device to address a perforated leaflet is feasible and can achieve durable results.