bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Preservative Potential of Essential Oils of Ocimum gratissimum from Bambili of the North West and Mbonge of the South West Regions of Cameroon on Scomber scombrus
Authors: Ndasi Ngwasiri Pride , Angu Tsi Celestine , Ambindei Wilson Agwanande , Edouard Nantia Akono , Yimta Diane Youmbi , Pierre Eke , Nguti Kien Agatha Tanya , Valere Tsouh Fokou Patrick
Published: April 2021

Essential oils serve as a natural alternative to chemical or synthetic antimicrobials and antioxidants to fight against food borne pathogens or spoilage organisms, inhibiting lipid peroxidation and extending the shelf life of fish and other seafood. This study examines the antibacterial properties of essential oils from leaves of Ocimum gratissimum L. from two localities of the North West and South West of Cameroon on some pathogenic spoilage gram negative and positive bacteria isolated from mackerel, and their antimicrobial and antioxidant effectiveness on the fish quality during preservation for one month at -18oC. The plant materials were harvested from Bambili, the North West Region of Cameroon and from Mbonge, the South West Region of Cameroon and the essential oils extracted by hydro-distillation using Clevenger-type apparatus. Escherichia coli, Salmonella typhi and Staphylococcus aereus were isolated from mackerel by culture techniques and their susceptibility to the essential oils determined by well diffusion method. Psychrophilic bacteria and Enterobacteraceae counts were used to evaluate the microbiological quality of the fish during storage. Total volatile basic nitrogen and thiobarbituric acid reactive substance assays were used as indices to assess the biochemical quality of the fish during storage. Antibacterial susceptibility test showed that essential oils of O. gratissimum from the North West and South West Regions were active on all the tested microorganisms with different degree.The inhibitory diameters for essential oil from the South West Region were 28.0 mm, 27.2 mm and 26.0 mm while that for essential oil from the Bambili were 24.1 mm, 20.4mm and 21.9 mm for Staphylococcus aereus, Escherichia coli and Salmonella typhi respectively. At the end of storage periods, the values of Psychrotrophs plate counts, total volatile base nitrogen and thiobarbituric acid reactive substances for fish samples treated with essential oil from the Mbonge were 2.71log10cfu/g, 12.88 mgN/100g and 0.88 mgMDA/Kg, while that treated with North West essential oil were 3.00 log10cfu/g, 16.24 mgN/100g and 1.26 mgMDA/Kg respectively. From the obtained results, essential oil of O. gratissimum from the Mbonge was the most effective in preserving Atlantic mackerel.
Ecosystem and Ecological Services; Need for Biodiversity Conservation-A Critical Review
Authors: Oguh C. E. , Obiwulu E. N. O. , Umezinwa O. J. , Ameh S. E. , Ugwu C. V. , Sheshi I. M.
Published: April 2021

Biodiversity and ecosystems are closely related concepts. Biodiversity provides numerous ecosystem services that are crucial and important to human well-being at present and in the future. The review aim to explain the Ecosystem services, and need for conservation of biodiversity. Ecosystem services (also called environmental services or nature’s services) are benefits provided by ecosystems to humans, which contribute to making human life both possible and worth living. Human kind fully depends on the earth’s ecosystems and the services they provide, such as food, water, disease management, climate regulation, spiritual fulfillment and aesthetic enjoyment. Over the past 50 years, humans have changed these ecosystems more rapidly and extensively than ever before, so that growing demands for food, fresh water, timber, fiber and fuel can be met. Pollution through the discharge of municipal and industrial wastewater and solid waste (e.g. plastics) exacerbates the related problems. Environmental pollution results from mishandling, deliberate disposal, spilling and leakage of waste products, such as gasoline, lubricating oils, diesel fuel, heating oil’s, used or spent engine oils, animal wastes, human excreta, certain dissolved organic compound (e.g. urea, carbohydrate etc.), and organic salts such as nitrates, soap, phosphates of detergent, sodium, potassium, calcium and chloride ions. Under natural process most of the biodegradable pollutants of sewage are rapidly decomposed, but when they accumulate in large quantities, they create problems, i.e., when their input into environment exceeds the decomposition or disposal capacity. Ecosystem health is inherently linked to water management, sanitation and agriculture as these aspects influence water availability and quality. The loss of biodiversity can reduce the provision of ecosystem services essential for human well-being. Therefore, sustainable sanitation and water management is crucial for a more sustainable ecosystem management in the future.
Knowledge, Attitudes and Practices of Healthcare Providers on Covid-19 in Kisangani, Democratic Republic of Congo
Authors: Bassandja Ossinga , Yakusu Issa , Kampunzu Muyobela , Bokota Lofoli , Folo Baelongandi , Isongibi Gilbert Bokungu , Likwela Losimba
Published: April 2021

Objective: Our study aimed to determine the level of knowledge, attitudes and practices (KAP) of healthcare providers towards Covid-19 in general hospitals in the city of Kisangani.

Methods: A descriptive cross-sectional study was undertaken among the providers of these general hospitals. KAP on Covid-19 were assessed using a survey questionnaire.

Results: Female providers were predominant (64%). The majority of respondents were between 25 and 34 years old. 21 were general practitioners (16.7%). The majority had sufficient knowledge (92.2%) provided mainly by radio and television. 77 had a negative attitude towards the possibility of containing the disease; and 88.1% had good practices with regard to Covid-19.
Relational Analysis of Profile of Bt Cotton Growers with their Adoption of Integrated Pest Management for Controlling Pink Bollworm
Authors: Deshmukh J. M. , Ghuge B. Y.
Published: April 2021

Maharashtra state particular has faced the problem of control of pink bollworm in cotton as a more pronounced during last year and the incidence has been identified from the middle of crop season seriously damaging the cotton in late pickings. Hence the Pink bollworm of Bt. (Bacillus thuringiensis) otton is the major pest in observed in this state. So the present study was conducted in Beed district of Marathwada region from Maharashtra state. In Beed district and three tehsils namely Beed, Wadwani and Majalgaonwere randomly selected on the basis of area under Bt cotton. From each tehsils 4 villages were randomly selected and from each village 10 respondents were randomly selected to comprise 120 respondents. How profile characters affecting adoption of IPM in Bt Cotton was the major objective of the study. Regarding independent variables age had negative significant relationship with their adoption of Integrated Pest Management for controlling pink bollworm. Independent variables of: i) education, ii) occupation, iii) land holding, iv) annual income, v) social participation, vi) economicmotivation, vii) innovativeness, viii) ix) risk orientation, and x) knowledge had significant relationship withtheir adoption of Integrated Pest Management for controlling pink bollworm and extension mcontact had positive and highly significant relationship with their adoption of Integrated Pest Management for controlling pink bollworm.
Anatomical Description of the Bony Segments that Make Up the Skull of the Puma Concolor Species
Authors: Saldivia Manuel , Castro Leandro , Zapata Katherine , Cardenas P.
Published: April 2021

The Puma concolor is one of the largest carnivores present in Chile, although its size varies according to the geographical area in which it is found. It is increasingly common to find them outside their habitat and more in our environment. Its ecology, reproduction and nutritional aspects are known, but very little about its anatomy, which creates a challenge in the veterinary morphological area that needs strengthening.

The present study consisted of an anatomical description of the skull of five adult specimens of Puma concolor (2 female and 3 male) in the veterinary anatomy laboratory of the Santo Tomás University, of the Puerto Montt headquarters and the Austral University of Valdivia headquarters. , which allowed a detailed study on the bone conformation of each structure present in the skull of these specimens. This allowed us to achieve results of morphological interests and deepening in the anatomy of this species.
The Serological Basis of the Correlation between Iron Deficiency Anemia and Thyroid Disorders in Women: A Community Based Study
Authors: Islam Riazul , Akter Kazi Mahmuda , Rahman Atikur , Khanam Nurun Nahar , Azad Salauddin Al , Islam Md. Raihanul , Farjana Mithila , Rahman Mohammad Habibur , Badal Md. Nasir Uddin , Ahmed Sharmin , Assaduzzaman .
Published: April 2021

Objectives: Iron Deficiency Anemia (IDA), a global public health problem may have an inimical effect on thyroid function, especially in women and children. This study was conducted to inspect the correlation between IDA and thyroid disorders in women of Bangladesh.

Methods: A cross-sectional study was conducted among 452 women of different age groups in particular regions of Bangladesh presenting anemic symptoms and were confirmed anemic after testing of serum hemoglobin levels less than 12 g/dL. To identify the correlation between iron deficiency anemia and thyroid disorders; serum samples were tested quantitatively through standardized methods considering serum iron, total iron-binding capacity (TIBC), ferritin, thyroid-stimulating hormone (TSH), free thyroxin (FT4), and vitamin D levels as parameters. Post clinical diagnosis statistical analysis, graphical presentations of the complex clinical data was generated using advanced computer programming language and bio-analytical tools.  

Results: A positive correlation between hypothyroidism and IDA in women was discovered in this study as 24.69% of patients with IDA from 0-60 years were found suffering from hypothyroidism simultaneously; with the highest percentage (38.46%) amongst the 31-40 years of age and 26% of iron-deficient females of reproductive age (15-49 years) were suffering from hypothyroidism. Moreover, the association between congenital hypothyroidism and IDA was noticed in 50% of cases above all.

Conclusion: Hypothyroidism was found quite common among the women of different age groups who were previously reported with acute to chronic anemia symptoms due to iron deficiency.
Knowledge, Perception, Attitude, Practice, and Barriers towards COVID-19 Infection among Saudi Residents in the Period of Rapid Outbreak of the Disease: A Cross Sectional Survey
Authors: Ansari Md Salahuddin , Al-Otaibi Faisal
Published: April 2021

The adherences to protective actions are subjective to knowledge, perception, attitude, practice and barriers towards COVID-19 by Saudi residents. The self-design questionnaires were used as a cross-sectional online survey for assessed their social and behavioral parameters during the agonizing time. The cross-sectional study used data collected via an online self-reported questionnaire from 2216 Saudi residents. SPSS software and chi-square test were applied to analyze and categorize significant differences among sectional variables of the parameters. More than 95% of responders were well aware about the main clinical symptoms of COVID-19 infection and had sufficient knowledge about the protocols of five steps to stop the spread of coronavirus. Apositive perception towards COVID-19 was observed, about 55% participants strongly agreed that the coronavirus outbreak could impact the global economy and infection could be successfully controlled by imposing lockdown and by staying at home. The majority of respondents had good practices regarding COVID-19 infection. A high percentage of participants favored wearing masks, cleaning hands and frequently using hand sanitizer. A large number of participant (83.2%; n=1844) agreed that misinformation and rumors are spreading more quickly than the current outbreak of the new coronavirus. The findings suggested that Saudi residents are possessed good knowledge, optimistic attitudes, and appropriate practices towards COVID-19 during the rapid rise of the COVID-19 outbreak. Hopefully, under the combined efforts of WHO, Ministry of Health, Saudi Arabia, all Saudi residents surely will win the battle against COVID-19 very soon.
A Systematic Review of the Clinical Studies in Humans for the Treatment of Severe Acute Respiratory Syndrome Coronavirus 2: Clinical Manifestation, Diagnosis and Clinical Trials
Authors: Belachew Girum Tefera , Hanumanthaiah Paramesh , Namo Fekede Meshesha , Tekelemariam Bitaniya Abera
Published: April 2021

Background: In December 2019 Chinese higher officials have acknowledged a number of cases of pneumonia happened in Wuhan, China with those patients who used the seafood from market selling live animals. At the end of December 2019, a kind of new pneumonia feast quickly in Wuhan, China, a novel coronavirus (2019-nCov).

Objective: Systematic analysis of the completed clinical trials in humans due to coronavirus disease in 2019 between January 12, 2020, to May 30, 2020 in 11 countries and possibly to recommend the ways to overcome the COV-2 pandemic.

Methods: Clinical studies completed in humans for the treatment of coronavirus disease in 2019 were looked for two databases, namely PubMed and Scopus. Based on the search terms, a total of 369 articles were downloaded. Of the total 369 articles, 38 duplicate articles were removed and 331 articles were screened with objective criterion. From the 331 articles, 168 articles were screened for excluded based on abstract screening and left with 163. Based on the exclusion criteria, 82 review articles, 51 articles not related to SARSCOV- 2 and 4 articles not written in English, in total 137 articles were excluded. Eventually, 26 articles were reviewed with required parameters for conclusive remarks.

Results: Of all the completed human clinical trials conducted in 11 countries obtained from https://clinicaltrials.gov/, the total patients included in the clinical trials from January 12, 2020 to May 30, 2020 were 6130. Out of them 1060 (17.29%) were only females and the rest 5070 (82.71%) were both males and females. From all patients studied, 163 patients were 30-70 years old, 60 patients were 60 years old, 2531 patients were of all age groups and the rest 3376 patients were ≥ 18 years old. Of all the completed clinical trials in 11 countries, eight different interventional models and four study types were used.

Conclusion: From the analysis of segregated results it is apparent that there was inclusion of patients with varied age group in the studies conducted with very less amount of patients from ≤ 18 years old, old age group and only females. The prime reason for least percentage inclusion of different age groups could be the weaker inherent immune response for the pandemic. COVID-19 can cause a conceivably deadly infection in humans. The most typical clinical manifestations reported by patients with coronavirus disease in 2019 were fever, cough, and expectoration. Approval of vaccines for control of COVID-19 is yet to be officially done, although now few vaccines are administered. Knowing the way to enter the cell and the mechanism on how to escape the immune system can be the potential targets to develop a novel SARS-COV-2 treatment protocol.
Preliminary Phytochemical Analysis and Spectroscopic Analysis Methanolic Extract of Asteracantha Longifolia (Nees.)
Authors: Veerakumar D. , Muthulingam M.
Published: April 2021

The present investigation was focused on the preliminary phytochemical, UV-VIS spectrum and Fourier Transform Infrared Spectral analysis of Asteracantha longifolia. The Methanolic extract from the leaves of Asteracantha longifolia  were tested for the availability of alkaloids, flavonoids, tannins, saponins, proteins, Terpenoids, Phenols, Steroids, Glycosides and Carbohydrates. The UV-VIS profile demonstrated various peaks ranging from 400-700 nm with various Extract respectively. The FT-IR spectrum confirmed the presence of secondary alcohols, alkanes, alkynes, aromatics, alkenes, sulphur, phosphorus, esters, hydrocarbons, nitrogen compounds (amines) in methanolic extract. The results of this study offer a platform of using Asteracantha longifolia leaves as herbal alternative for various diseases including diabetic, cardiovascular etc. The results of this study offer a platform of using Asteracantha longifolia leaves as herbal alternative for various diseases including cancer and diabetic.
The Histopathological Study of Gastrointestinal Polyps
Authors: Subramanian Vidhya , Rao G. Bheema , Thanka J.
Published: April 2021

Polyps covered by non-neoplastic squamous epithelium may develop anywhere in the esophagus. Squamous polyps may be divided in to two types: Inflammatory polyps and squamous papillomas. To study the incidence and morphology of Gastro Intestinal Tract polyps from specimens received at Sree Balaji Medical College and Hospital, Chennai. To analyze the incidence and morphological features of malignancies associated with polyps. Of the 102 cases, intestinal cancer was found predominately 51(50%) followed by stomach. The ages ranged from 17 to 77 yrs and average was 44 yrs. The female ratio was 0.77.  Expression of P53 was varied with the property of the polyps and it could be a useful marker for determining the treatment regime.
Melittin‐induced fusion of acidic liposomes
Authors: Eytan Gera D. , Almary Taiser
Published: July 2002

Melittin‐induced fusion of acidic liposomes. Fusion was observed in the electron‐microscope and assayed as intermixing of both liposomes' contents and membranes. The melittin concentrations required for fusion induction were in the μM range compared to over 10 mM Ca2+ required for a comparable effect. It is suggested that the high efficiency of melittin is due to its amphipathic nature. Its hydrophobic moiety is probably anchored in one liposome while the positively charged hydrophilic moiety attracts another liposome.
Evidence for the glycoprotein nature of the crystalline cell wall surface layer of Bacillus stearothermophilus strain NRS2004/3a
Authors: Küpcü Zaruhi , März Leopold , Messner Paul , Sleytr Uwe B.
Published: July 2002

The surface layer of Bacillus stearothermophilus strain NRS2004/3a was isolated and chemically characterized. The results of these initial studies lead to the conclusion that the cell surface protein is glycosylated.
A high‐molecular‐mass cell wall protein released from Clostridium tyrobutyricum by heat treatment
Authors: Hayes Hélène , Commissaire Jacqueline , Bergere Jean-Louis
Published: July 2002

Clostridium tyrocutyricum Cell wall
Protein
Uric acid substantially enhances the free radical‐induced inactivation of alcohol dehydrogenase
Authors: Kittridge K.J. , Willson R.L.
Published: July 2002

Lactate dehydrogenase (LDH) and yeast alcohol dehydrogenase (YADH) are inactivated when attacked by hydroxy free radicals (OH·). Organic molecules with a high rate constant of reaction with OH· such as ascorbate or urate can compete with the enzymes for these strongly oxidising radicals. However, although 10−3 M ascorbate can substantially protect both LDH and YADH from OH· attack, in the presence of 10−3 M urate only LDH is protected. In the case of YADH an even greater degree of inactivation than with OH· occurs. The extent of inactivation is considerably reduced when oxygen is absent, in agreement with a urate peroxy radical perhaps being partly responsible for the increased inactivation of the enzyme.
A novel side‐chain‐linked antiparallel cyclic dimer of enkephalin
Authors: Schiller Peter W. , Nguyen Thi M.-D. , Lemieux Carole , Maziak Louise A.
Published: July 2002

The dimeric cyclic enkephalin analog, (was isolated as a second major component from the crude product obtained in a solid‒phase synthesis of the corresponding cyclic monomer,. In comparison with [Leu5]enkephalin the cyclic dimer is about equipotent in assays representative for μ‒opioid receptor interactions and
as potent at the δ‒receptor. The fact that the enkephalin dimer shows a receptor selectivity pattern distinct from that of the cyclic monomer and of the corresponding linear analog suggests that cyclodimerization via side‒chain linkages might be generally useful as a means to produce shifts in the activity profiles of peptide hormones and neurotransmitters.
1,4‐Thiomorpholine‐3,5‐dicarboxylic acid, a novel cyclic imino acid detected in bovine brain
Authors: Cavallini D. , Matarese R.M. , Pecci L. , Ricci G.
Published: July 2002

Gas‐liquid chromatography of enriched bovine brain extract revealed the occurrence of several sulfur‐containing compounds. By co‐chromatography with authentic product and by mass‐spectrometric analysis, one of these compounds has been identified as 1,4‐thiomorpholine‐3,5‐dicarboxylic acid (TMDA). The possible derivation of TMDA from lanthionine is discussed. This represents the second S‐containing cyclic imino acid so far discovered in a mammalian brain whose physiological significance has not yet been explored.
Structural evidence for three different types of glutathione transferase in human tissues
Authors: Ålin Per , Mannervik Bengt , Jörnvall Hans
Published: July 2002

Cytosolic glutathione transferase was purified from human placenta and human liver. Three different forms of the enzyme were obtained, the acidic (π), the near‐neutral (μ), and the basic (α‐ϵ) forms; two had free α‐amino groups (π,μ) and one had a blocked α‐amino group (α‐ϵ). N‐terminal sequence analyses and total compositions gave clearly different results for each form, although transferases π and μ showed 35% sequence homology in the N‐terminal regions, with a 1‐residue shift in starting position. Consequently, the proteins are concluded to be products of three discrete but related genes.
5‐Fluoroorotate: a new liposome‐dependent cytotoxic agent
Authors: Heath Timothy D. , Lopez Ninfa G. , Stem Walter H. , Papahadjopoulos Demetrios
Published: July 2002

The potency of 5‐fluoroorotate for inhibition of L929 or CV1‐P cell growth is increased by encapsulation in negatively charged liposomes. The optimal liposome composition is dipalmitoylphosphatidylglycerol: cholesterol, 67:33. Unextruded large unilamellar liposomes are the optimal size for delivery. This compound is the second transport‐negative drug which we have found to exhibit liposome‐dependent delivery.
Epidermolytic toxin from Staphylococcus aureus binds to filaggrins
Authors: Smith Thomas P. , Bailey Christopher J.
Published: July 2002

The affinity of epidermolytic toxin from Staphylococcus aureus for proteins from the target tissue has been tested by a Western blotting procedure. Particular proteins in a l M phosphate extract of epidermis reacted on nitrocellulose blots with a probe prepared by the conjugation of toxin with peroxidase. Protein extracted into 50 mM Tris‐HCl did not react. The probe detected profilaggrin, filaggrin and a smaller unidentified polypeptide. It is suggested that the interaction is relevant to the mode of action of the toxin.
Mechanism of o‐aminophenol metabolism in human erythrocytes
Authors: Tomoda Akio , Yamaguchi Jundo , Kojima Hisanori , Amemiya Hidemitsu , Yoneyama Yoshimasa
Published: July 2002

o‐Aminophenol was found to be rapidly metabolized to a brown compound in the presence of purified human oxy‐ and methemoglobin, coupled with the oxidation and reduction of these hemoglobins by o‐amino‐phenol. The final product of o‐aminophenol was identified as 2‐aminophenoxazine‐3‐one, by using spectrophotometry and HPLC. The metabolism of o‐aminophenol was also observed in human erythrocytes. The production rates of 2‐aminophenoxazine‐3‐one in the cells were very fast, but these were strongly decreased by bubbling carbon monoxide into the cell suspension when intracellular hemoglobin was in the ferrous state. The production of 2‐aminophenoxazine‐3‐one from o‐aminophenol in the cells was completely suppressed by cyanide and azide when intracellular hemoglobin was in the ferric state. These results suggest that oxy‐ and methemoglobin are involved in metabolism of o‐aminophenol to 2‐aminophenoxazine‐3‐one in human erythrocytes.
Stable transformation of Drosophila Kc cells to antibiotic resistance with the bacterial neomycin resistance gene
Authors: Maisonhaute Claude , Echalier Guy
Published: July 2002

By transfection with a plasmid containing the APH(3́) gene under control of the HSV I thymidine kinase promoter, independent series of stably transformed Drosophila cells were established and grown for more than one and a half years under highly selective pressure (2 mg G 418/ml). Analysis of transformed Drosophila cell DNAs shows that the APH(3́) gene was integrated into the genome. Neomycin phosphotransferase is constitutively expressed in transformed cells. This efficient selective system by a dominant marker makes it possible to introduce, by cotransfection, any DNA sequence of interest into the genome of cultured Drosophila cells.
Native and chemically modified porin channels from Salmonella typhi Ty2 in planar lipid bilayers
Authors: Labarca Pedro , Lobos Sergio , Calderón Inés , Mora Guido
Published: July 2002

Native porins, from Salmonella typhi Ty2 outer membrane, and porins alkylated with pyridoxal phosphate (Plp) were studied in planar lipid bilayers. The conductance of bilayers exposed to native or chemically modified porins increases in discrete jumps. Conductance histograms for native porins displayed two major peaks at 1.7 and 6.7 nS (in 0.5 M KCl). On the other hand, Plp‐treated porins exhibited a single major peak at 1 nS. The relation between bilayer conductance and native porin concentration was linear. However, this relation became logarithmic in the presence of modified porins. The results support the notion that alkaline reduction of S. typhi Ty2 porins with Plp dissociates porin channel trimers in a reversible fashion.
Electrogenic reduction of the secondary quinone acceptor in chromatophores of Rhodospirillum rubrum
Authors: Kaminskaya Olga P. , Drachev Lel A. , Konstantinov Alexander A. , Semenov Alexey Yu. , Skulachev Vladimir P.
Published: July 2002

Electron transfer QA → QB has been reconstituted with added Q‐10 in Rhodospirillum rubrum chromatophores associated with a phospholipid‐impregnated collodion film. Rapid kinetics measurements of laser flash‐induced ΔΨ generated in the chromatophores show that whereas electron transfer from Qa
− to QB upon the first flash is not electrogenic in dark‐adapted chromatophores, reduction of Q−
B to Qbh2 induced by the second flash gives rise to an electrogenic phase with τ = 250 μs at pH 7.5 which contributes about 10% to the total ΔΨ generated upon the flash. The electrogenic phase is ascribed to vectorial protonation of Q2−
B.
Occurrence of a novel glycolipid, 'trehalose 2,3,6'‐trimycolate' in a psychrophilic, acid‐fast bacterium, Rhodococcus aurantiacus (Gordona aurantiaca)
Authors: Tomiyasu Ikuko , Yoshinaga Junji , Kurano Fusako , Kato Yoshiko , Kaneda Kenji , Imaizun Sadao , Yano Ikuya
Published: July 2002

A new type of glycolipid possessing trehalose and mycolic acids has been identified in the lipids of Rhodococcus aurantiacus (Gordona aurantiaca), a psychrophilic acid‐fast bacterium. Gas Chromatographic and gas chromatographic‐mass spectrometric analysis of hydrolysis products of the most abundant glycolipid class (GM) (containing approx. 50% of the total lipids) showed that the hydrophilic moiety was composed essentially of trehalose, while the hydrophobic moiety contained C62‐74 polyunsaturated mycolic acids only. Permethylation study revealed that the new glycolipid possessed three mycolic acid residues for each trehalose molecule and was identified as trehalose 2,3,6'‐trimycolate.
The second pX product p27x‐III of HTLV‐1 is required for gag gene expression
Authors: Inoue Jun-ichiro , Seiki Motoharu , Yoshida Mitsuaki
Published: July 2002

The human T‐cell leukemia virus type‐1 (HTLV‐1) contains a unique pX region, which encodes the gene products p40
x
, p27
x‐III
and p21
x‐III
. p40
x
is required for transcriptional trans‐activation, whereas p27
x‐III
and p21
x‐III
have no such function. Transfection of pX expression plasmids containing different combinations for the three gene products into cells integrated with HTLV‐1 proviruses defective in pX expression revealed that both p40
x
and p27
x‐III
are required for expression of the gag protein and accumulation of gag mRNA. These observations suggest that the pX product p40
x
activates transcription and p27
x‐III
controls the level of gag mRNA by post‐transcriptional modulation.
Point mutations of human interleukin‐1 with decreased receptor binding affinity
Authors: MacDonald H.Robson , Wingfield Paul , Schmeissner Ursula , Shaw Alan , Clore G.Marius , Gronenborn Angela M.
Published: July 2002

Interleukin‐1 (IL‐1) is a monocyte‐derived polypeptide hormone that interacts with a plasma membrane receptor. We have used oligonucleotide‐directed mutagenesis to construct mutant human IL‐1 proteins. Three different point mutants in a unique histidine residue (position 30) exhibited varying degrees of reduced IL‐1 receptor binding affinity, whereas point mutants at five other residues behaved normally. Structural analysis of these mutant proteins by nuclear magnetic resonance spectroscopy detected no (or only minor) conformational changes relative to wild‐type IL‐1. These data suggest that the unique histidine residue influ‐ ences the architecture of the receptor binding site on human IL‐1.
Mode of inhibition of sodium azide on H+‐ATPase of Escherichia coli
Authors: Noumi Takato , Maeda Masatomo , Futai Masamitsu
Published: July 2002

Sodium azide inhibited multi‐site (steady‐state) ATPase activity of E. coli F1 more than 90%, but did not affect uni‐site (single‐site) ATPase activity. Thus azide inhibited multi‐site ATPase activity by lowering catalytic cooperativity. Consistent with this observation, azide changed the ligand‐induced fluorescence response of aurovertin bound to F1.
Demonstration of immunochemical identity between the synaptic vesicle proteins synaptin and synaptophysin/p38
Authors: Gaardsvoll Henrik , Obendorf Dieter , Winkler Hans , Bock Elisabeth
Published: July 2002

The synaptic vesicle proteins synaptin and synaptophysin/p38 were shown to be immunochemically identical. Western immunoblot analysis of Triton X‐100 extracts from rat brain showed that polyclonal polyspecific anti‐synaptin antibodies and monoclonal antibody SY38 against synaptophysin both reacted with a band of 38 kDa. In two‐dimensional immunoblots of chromaffin granule membranes from bovine adrenal medulla anti‐synaptin and anti‐synaptophysin antibodies also recognized the same component. Finally, in a Western immunoblotting experiment SY38 reacted with an immunoisolated synaptin antigen.
Heterogeneous expression of glutamine synthetase mRNA in rat liver parenchyma revealed by in situ hybridization and Northern blot analysis of RNA from periportal and perivenous hepatocytes
Authors: Gebhardt R. , Ebert A. , Bauer G.
Published: July 2002

Using radiolabeled specific cDNA glutamine synthetase mRNA could be detected by in situ hybridization exclusively within those few perivenous hepatocytes which stained immunocytochemically for glutamine synthetase. This localization of glutamine synthetase mRNA was recently reported by Moorman et al. [(1988) J. Histochem. Cytochem. 36, 751–755]. Biotinylated cDNA was not suitable for mRNA detection because of a very high background staining under the conditions of in situ hybridization. Dot blot and Northern blot analysis of RNA isolated from periportal and perivenous subfractions of hepatocytes also demonstrated the exclusive perivenous localization of two hybridizable glutamine synthetase mRNAs of length 2.8 and 1.6 kilobases. These results indicate that the unique heterogeneity of glutamine synthetase in rat liver parenchyma is controlled at the pretranslational level.
1,2‐sn‐Diacylglycerol accumulates in choline‐deficient liver
Authors: Blusztajn Jan Krzysztof , Zeisel Steven H.
Published: July 2002

Choline deficiency is associated with triacylglycerol accumulation in the liver, and is the only nutritional state known to trigger hepatic cancer spontaneously. In two different experiments, rats were pair‐fed for 6 weeks with control (0.2% choline), or choline‐deficient (CD) (0.002% choline) diets. Hepatic choline and phosphocholine declined in CD animals to 54% and 16% of control levels, respectively. In control livers, 1,2‐sn‐diacylglycerol (1,2‐sn‐DAG) concentration was (in nmol/g wet wt) 144 (± 25; mean ± SE); while in CD livers it was 792 (± 140) in the first experiment. In the second experiment the values were 375 (± 26) and 1147 (± 74), respectively. 1,2‐sn‐DAG, a precursor of triacylglycerol, is an endogenous activator of protein kinase C (PKC). PKC is the presumed site of action of the tumor‐promoting phorbol esters. We suggest that the 1,2‐sn‐DAG accumulating in CD liver could bind PKC, altering its activity, and thus contribute to the carcinogenic effect of CD diets.
Purification and crystallization of ferric enterobactin receptor protein, FepA, from the outer membranes of Escherichia coli UT5600/pBB2
Authors: Jalal M.A.F. , van der Helm D.
Published: July 2002

The ferric enterobactin receptor protein, FepA, was isolated and purified from the outer membranes of a genetically transformed strain of Escherichia coli (UT5600/pBB2) using anion‐exchange chromatography, chromatofocusing and gel filtration. The purified protein was found to crystallize from 25 mM sodium phosphate buffer in the presence of 0.8% β‐D‐octylglucoside under a range of conditions. The protein formed mostly small rods and needle‐shaped crystals in the hanging drop method.
A porin‐type protein is the main constituent of the cell envelope of the ancestral eubacterium Thermotoga maritima
Authors: Rachel Reinhard , Engel Alfred M. , Huber Robert , Stetter Karl-O. , Baumeister Wolfgang
Published: July 2002

Thermotoga maritima is an extremely thermophilic eubacterium and represents the deepest known branch and the most slowly evolving line within this kingdom. This bacterium possesses a sheath‐like envelope which forms characteristic balloons (the ‘toga’) around the cell poles. We have shown by electron microscopy in conjunction with image processing and by biochemical analyses that this sheath is essentially an outer membrane. Its predominant 42 kDa protein, which is regularly arrayed in vivo, has all the characteristics of the trimeric porins known from the phylogenetically very distant proteobacteria. This was an unexpected finding, which has some interesting evolutionary implications.
Finnish hereditary amyloidosis is caused by a single nucleotide substitution in the gelsolin gene
Authors: Maury C.P.J. , Kere J. , Tolvanen R. , de la Chapelle A.
Published: July 2002

The amyloid protein in Finnish hereditary amyloidosis is a fragment of the actin‐filament binding region of a variant gelsolin molecule. Here we demonstrate, using polymerase chain reaction and allele‐specific oligonucleotide hybridization analyses of genomic DNA, a single base mutation (G654 → A654) in the gelsolin gene segment encoding the amyloid protein. The mutation is responsible for the expression of the variant (Asn187) gelsolin molecule in Finnish hereditary amyloidosis. The nucleotide substitution was found in all five unrelated patients with Finnish amyloidosis studied, but not in 45 unrelated control subjects. The mutation co‐segregated with the disease phenotype in a family with Finnish amyloidosis. The results show that a single substitution in the gelsolin gene causes Finnish hereditary amyloidosis. The allele‐specific oligonucleotide hybridization method provides a simple and accurate means of detecting this mutation.
Treatment of human peripheral lymphocytes with concanavalin A activates expression of glutathione reductase
Authors: Arnold H.H. , Heinze H.
Published: July 2002

A cDNA clone corresponding to mRNA present only in proliferating cells was isolated and its nucleotide sequence determined. This cDNA is 723 nucleotides long and encodes a portion of the human glutathione reductase mRNA corresponding to the amino acids 77–318 of the mature protein. Expression of glutathione reductase mRNA was undetectable in resting human T‐lymphocytes and was induced shortly after cells had been triggered to proliferate by the treatment with concanavalin A. This result suggests that synthesis of glutathione reductase is generally activated in replicating cells which may indicate that this enzyme plays a functional role during cell proliferation.
DNA methylation and chromatin structure
Authors: Lewis Joe , Bird Adrian
Published: July 2002

Studies of the whole genome by molecular and cytogenetic methods have implicated DNA methylation in the formation of ‘inactive chromatin’. This has been confirmed by analysis of specific endogenous sequences, and has been mimicked by introducing methylated and non‐methylated sequences into cells. As well as affecting chromatin structure, DNA methylation also represses transcription. A protein (MeCP) which binds specifically to methylated DNA has been identified, The properties of MeCP could account for the effects of DNA methylation on both chromatin and transcription.
The 93 kDa protein gephyrin and tubulin associated with the inhibitory glycine receptor are phosphorylated by an endogenous protein kinase
Authors: Langosch Dieter , Hoch Werner , Betz Heinrich
Published: July 2002

The 93 kDa protein gephyrin is a tubulin binding peripheral membrane protein that is associated with the inhibitory glycine receptor and has been implicated in its anchoring at central synapses. Here, we demonstrate that gephyrin as well as co‐purifying tubulin are phosphorylated by a kinase activity which is endogenous to highly purified glycine receptor preparations. This kinase phosphorylates serine and threonine residues and utilizes ATP, but not GTP, as phosphate donor. Its activity is not affected by various activators and/or inhibitors of cyclic nucleotide‐dependent kinases, calcium/calmodulin‐dependent kinases, or protein kinase C. A five‐fold stimulation of kinase activity was, however, observed in the presence of poly‐lysine. Phosphorylation of gephyrin and/or tubulin might regulate receptor/cytoskeleton interactions at postsynaptic membrane specializations.
Visualization of the morphology of purple membrane surfaces by monoclonal antibody techniques
Authors: Yamaguchi Naoto , Jinbo Yumiko , Arai Masao , Koyama Koichi
Published: July 2002

A monoclonal antibody technique for determining the surface morphology of the purple membrane (PM) has been developed. Two types of antibodies for distinguishing the extracellular surface and the cytoplasmic surface of PM were produced by immunizing the corresponding synthetic peptides to mice. The Langmuir‐Blodgett (LB) method was employed to form a single‐layer two‐dimensional array of PM fragments on an electron microscope grid. The LB film was then treated with the antibodies which had been labeled with colloidal gold particles. Electron microscope observations visualized the morphology of the two surfaces of PM to be rough and smooth regions, respectively; thus the orientation of PM fragments was determined.
Superoxide enhances the spread of HIV‐1 infection by cell‐to‐cell transmission
Authors: Kameoka Masanori , Kimura Takuro , Ikuta Kazuyoshi
Published: July 2002

Oxidative stress is thought to be involved in the progression of human immunodeficiency virus type 1 (HIV‐1)‐induced disease. We examined the effect of Superoxide (O2
−) on HIV‐1 spread in cultured human CD4+ cell lines. The O2
− significantly enhanced cell‐to‐cell transmission of HIV‐1, although its effect on HIV‐1 replication was not evident, presumably due to its cytostatic activity. The effect was notable on the HIV‐1 transmission from macrophages to T lymphocytes by endogenous, macrophage‐generated O2
−. This amplification was specifically reduced to the steady‐state level by antioxidants, and further to the basal level by anti‐CD4 antibodies, indicating the specificity of O2
− for enhancing HIV‐1 spread by cell‐to‐cell transmission.
A survey of a functional amino acid of class Cβ‐lactamase corresponding to Glu166 of class A β‐lactamases
Authors: Nukaga Michiyoshi , Tanimoto Kyoko , Tsukamoto Kikuo , Imajo Seiichi , Ishiguro Masaji , Sawai Tetsuo
Published: July 2002

The class C β‐lactamase of Cltrobacter freundii GN346 is a typical cephalosporinase comprising 361 amino acids. The aspartic acid at position 217 and glutamic acid at position 219 in this β‐lactamase were, respectively, previously shown not to be the counterpart of Glu166 (ABL166) in class A β‐lactamases, even though sequence alignment of class A and C enzymes strongly suggested this possibility [(1990) FEBS Lett. 264, 211‐214; (1990) J. Bacteriol. 172, 4348‐4351]. We tried again to assign candidates for the counterpart of Glu166 through sequence alignment based on other criteria, the glutamic acids at positions 195 and 205 in the class C β‐lactamase being selected. To investigate this possibility, these two glutamic acids were changed to glutamine, lysine or alanine, respectively. All the mutant enzymes showed more than 50% of the activity of the wild‐type enzyme, indicating that the possibility was ruled out. These results strongly suggested the possibility that the class C β‐lactamase lacks a functional acidic residue corresponding to Glu166 in class A enzymes.
Phosphorylation of the L‐type calcium channel β subunit is involved in β‐adrenergic signal transduction in canine myocardium
Authors: Haase Hannelore , Karczewski Peter , Beckert Ralf , Krause Ernst Georg
Published: July 2002

Cyclic AMP‐mediated phosphorylation of calcium channel submits was studied in vitro and in vivo in preparations from dog heart. Calcium channels in native cardiac membranes were phosphorylated by cAMP‐dependent protein kinase (PKA) solubilized with digitonin and subsequently immunoprecipitated using a polyclonal antibody generated against the deduced carboxy‐terminal sequence of the cardiac β subunit. A 62 kDa protein was identified as the major PKA‐substrate in the immunoprecipitates. In the intact myocardium, this putative β subunit was found to be phosphorylated in response to cAMP elevating agents. In contrast, no phosphorylation of a protein with an electrophoretic mobility similar to the α1 subunit was detected, although 1,4‐dihydropyridine receptor sites were recovered in the immunoprecipitates. Thus, we suggest that PKA‐mediated phosphorylation of the β subunit is the major mechanism for β‐adrenergic regulation of cardiac L‐type calcium channel activity.
Exon/intron organization of the gene encoding the mouse epithelin/granulin precursor (acrogranin)
Authors: Baba Tadashi , Nemoto Hiromi , Watanabe Ken , Arai Yuji , Gerton George L.
Published: July 2002

Mouse genomic clones encoding the epithelin/granulin gene and its 5′‐ and 3′‐flanking regions have been isolated and sequenced. This gene was found to be a single‐copy gene, and contained 13 exons interrupted by 12 introns. Eight out of the 12 introns are classified as phase 0, and are located within the central part of each of the tandem repeats in the amino acid sequence of the epithelin/granulin precursor. The first intron is unique because of the interruption of the 5′‐untranslated region and its fairly large size (approximately 2.4 kbp). Consensus sequences for several of the potential regulatory elements are present in the 5′‐flanking sequence, including a common CCAAT sequence.
Recognition signal for the C‐terminal processing protease of D1 precursor protein in the photosystem II reaction center An analysis using synthetic oligopeptides
Authors: Taguchi Fumiko , Yamamoto Yumiko , Inagaki Noritoshi , Satoh Kimiyuki
Published: July 2002

Synthetic oligopeptides of different chain lengths of 11 to 38 amino acids, corresponding to the carboxyl‐terminal sequence of D1 precursor protein of the photosystem II reaction center, were subjected to a proteolytic cleavage by a processing enzyme isolated from spinach, in order to analyze the recognition signal. Practically the same K
m and V
max values were obtained for the oligopeptides consisting of more than 19 amino acids; a decrease in affinity, without affecting the V
max value, was observed for the peptide consisting of 16 amino acids; no detectable activity was found for the peptide with 11 amino acids. When Asp‐342 (12th residue from C‐terminus) was replaced with Asn, for the peptide consisting of 16 amino acids, the enzymatic activity was completely abolished. In contrast, replacing Asp‐342 with Glu had little effect. The efficiency of these oligopeptides as a substrate mentioned above, together with their effectiveness as an inhibitor, clearly demonstrated that the negative charge on Asp‐342 plays a crucial role in the recognition, i.e. binding and cleavage, of the substrate by the processing enzyme, and suggested that the carboxyl‐terminal extension consisting of 9 amino acids, by itself is not important in the binding.
Myelin membrane biogenesis by oligodendrocytes Developmental regulation of low molecular weight GTP‐binding proteins
Authors: Huber Lukas A. , Madison Dana L. , Simons Kai , Pfeiffer S.E.
Published: July 2002

Oligodendrocytes synthesize dramatic amounts of myelin membrane. We hypothesized that this requires unique aspects of vesicular trafficking. Specific stages of the oligodendrocyte lineage were assayed for low molecular weight GTP‐binding proteins implicated in the regulation of vesicular transport pathway (two dimensional gel electrophoresis, [α‐32P]GTP overlay). Consistent with the hypothesis, as oligodendrocytes differentiate from early progenitors to mature myelin‐producing cells, ≥≥ 12 small GTP‐binding proteins become up‐regulated. Myelin membrane also has a complex pattern of GTP‐binding proteins. Several of these proteins may be specific to oligodendrocytes, suggesting that oligodendrocytes may utilize cell‐type specific GTP‐binding proteins for biogenesis and maintenance of the myelin membrane.
Regulation by glucose of the biosynthesis of PC2, PC3 and proinsulin in (ob/ob) mouse Islets of Langerhans
Authors: Martin Sean K. , Carroll Raymond , Benig Michelle , Steiner Donald F.
Published: July 2002

The prohormone convertases PC2 and PC3 have been shown to catalyze the processing of proinsulin to insulin in pancreatic β‐cells. In these studies we have compared the effects of glucose on PC2 and PC3 biosynthesis in freshly isolated islets from normal and hyperglycemic (ob/ob) mice. In contrast to normal islets [Alarcón, et al. (1993) J. Biol. Chem. 268, 4276] the biosynthesis of both PC2 and PC3 is stimulated by glucose, parallel to the stimulation of proinsulin in the (ob/ob) islets. Inhibition of PC2 biosynthesis by glucose in normal islet non β‐cells may obscure stimulation of PC2 biosynthesis in normal islet β‐cells.
Effects of calcium ions on proteolytic processing of HIV‐1 gp160 precursor and on cell fusion
Authors: Moulard Maxime , Montagnier Luc , Bahraoui Elmostafa
Published: July 2002

Complete activation of human immunodeficiency virus type 1 (HIV‐1) requires the endoproteolytic cleavage by cellular protease of the envelope glycoprotein precursor (gp160) into the external glycoprotein gp120, and the transmembrane glycoprotein gp41. We report here the effect of depletion of cellular calcium ions on maturation of precursor gp160 and its concomitant effect on syncytium formation. We show that the cellular endoprotease activity responsible for gp160 maturation and the capacity for HIV‐1 to induce syncytium formation are calcium‐dependent. In addition, we show that endoproteolytic maturation is a key step in syncytium formation induced by HIV‐1.