bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutations in the Tryptophan Operon Allow PurF-Independent Thiamine Synthesis by Altering Flux In Vivo
Authors: Ramos Itzel , Vivas E. I. , Downs D. M. 
Published: June 2007

ABSTRACT

Phosphoribosyl amine (PRA) is an intermediate in purine biosynthesis and also required for thiamine biosynthesis in
Salmonella enterica
. PRA is normally synthesized by phosphoribosyl pyrophosphate amidotransferase, a high-turnover enzyme of the purine biosynthetic pathway encoded by
purF
. However, PurF-independent PRA synthesis has been observed in strains having different genetic backgrounds and growing under diverse conditions. Genetic analysis has shown that the anthranilate synthase-phosphoribosyltransferase (AS-PRT) enzyme complex, involved in the synthesis of tryptophan, can play a role in the synthesis of PRA. This work describes the in vitro synthesis of PRA in the presence of the purified components of the AS-PRT complex. Results from in vitro assays and in vivo studies indicate that the cellular accumulation of phosphoribosyl anthranilate can result in nonenzymatic PRA formation sufficient for thiamine synthesis. These studies have uncovered a mechanism used by cells to redistribute metabolites to ensure thiamine synthesis and may define a general paradigm of metabolic robustness.
A CASE OF CEREBRAL MUCORMYCOSIS DIAGNOSED IN LIFE, WITH EVENTUAL RECOVERY
Authors: Muresan Augustin 
Published: June 2007

A case of mucormycosis localized in the brain is reported in a subject aged 18 years who was not suffering from diabetes. As the patient displayed symptoms of cerebral compression he was operated upon and a cystic formation was excised.Microscopic examination disclosed the presence of hyphae, displaying the characteristics of mucor, in chronic granulation tissue. The mycelia had a tendency to develop in the vessels and to invade them, and a structure very similar to a sporangium could be observed. Some of the mycelia had undergone dystrophic calcification.The patient has been kept under medical supervision for two and a half years since the operation and appears to have completely recovered.
THE BACTERIOLOGY OF URINARY INFECTIONS IN PARAPLEGIA
Authors: Scott T. G. 
Published: June 2007

Two hundred and forty-seven strains of micro-organisms were isolated from the urinary tract of 121 patients with neurological complaints leading to paraplegia. The commonest infecting organism wasE. coliand the commonest type of Proteus wasP. mirabilis. Infections with more than one type of organism were present in 37% of urine specimens, and in such cases the incidence ofE. coliwas lower and that ofStrep. faecalishigher than the incidences in infections with only one type of organism.No evidence was found which might suggest that the various bacterial species encountered showed either an undue degree of synergism or of mutual antagonism.Coliforms were the commonest primary pathogens, butStrep. faecalisand Proteus species occurred with the same frequency as the coliforms when they were considered as secondary invaders.The variance between the incidences of various species as reported by different workers is considered to be due to the different illnesses and conditions which predispose to urinary tract infection. It appears that infections in the urinary tract by more than one type of organism at a time occur more frequently in those patients with the more chronic predisposing causes. (Some disparity in findings may also result from the differing taxonomic methods employed by different workers, but this is probably insufficiently important to account for the largest differences.)
THROMBOTIC THROMBOCYTOPENIC PURPURA
Authors: Bornstein B. , Boss J. H. , Casper J. , Behar M. 
Published: June 2007

A case of thrombotic thrombocytopenic purpura in a 50-year-old woman is described. Almost the whole course of the disease, lasting 18 months, was characterized by a bizarre neurological disorder, and the haematological manifestations first appeared at a late stage.In many organs a vast number of arterioles and capillaries contained plugs of a fibrinoid material, and fibrinoid was subendothelially accumulated in a few of these vessels; but, in addition, mediumsized arteries of the myocardium were also obstructed by this same material. There were also verrucal endocardiosis of the mitral valve and slight thickening of the glomerular basement membranes. The striking diffusion of a pathological substance through damaged cerebral vessel walls into the nervous tissue seems to be a significant contribution to the understanding of the pathogenesis of the vascular pathology of thrombotic thrombocytopenic purpura.
THE COLICINE TYPING OF COLIFORM BACILLI IN THE STUDY OF CROSS-INFECTION IN UROLOGY
Authors: Linton K. B. 
Published: June 2007

Three hundred and fourteen strains of coliform bacilli (79Klebsiellaand 235E. coli), mostly isolated from urine, were investigated for their production of, or sensitivity to, certain colicines.Only oneKlebsiellastrain showed colicine activity, but in 204 of theE. colistrains colicine production or sensitivity was demonstrated.Colicine typing was of considerable value in epidemiological investigations of post-operative urinary infections due toE. coli.
SERUM TRANSAMINASES AND ISOCITRIC DEHYDROGENASE IN KWASHIORKOR
Authors: Baron D. N. 
Published: June 2007

Serum glutamic oxalacetic transaminase (G-OT), glutamic-pyruvic transaminase (G-PT), and isocitric dehydrogenase (ICD) have been estimated in six groups of subjects, namely, normal British adults, normal Nigerian adults, undernourished Nigerian adults and children, Nigerian children with florid protein malnutrition (kwashiorkor), and cases of protein malnutrition after treatment.The normal range in Nigerian adults was apparently slightly lower than in European adults.A marked increase in serum enzyme activity was found in florid malnutrition, and a slight rise in undernutrition. In all cases serum G-PT showed lesser changes than G-OT and ICD.The causes of these abnormalities are discussed. The increased serum enzyme activity is thought to be derived primarily from the liver and possibly also from voluntary muscle. Estimation of serum enzymes is recommended in the investigation of protein malnutrition.
THE BUFFERED PERFORMIC-ACID-ALCIAN-BLUE-PERIODIC-ACID-SCHIFF METHOD FOR THE DIFFERENTIATION OF BASOPHILS IN THE HUMAN AND RAT PITUITARY
Authors: Swettenham K. 
Published: June 2007

The difficulty of using a single method for staining rat and human pituitary was investigated by testing separately and in different combinations the effects of the various components in the performic-acid-alcian-blue(P.F.A.B.)-periodic-acid-Schiff(P.A.S.) method (Adams and Swettenham, 1958). In this way the possibility of inhibiting or enhancing by one procedure the staining effects of the other could be assessed. The profound influence of fixation on these staining methods was demonstrated by employing the same set of staining methods on tissues fixed in different ways.The possibility that unbuffered performic acid might exert a considerable solvent action on certain proteins was considered to be related to the difficulty of applying the P.F.A.B.-P.A.S. method to the rat pituitary. Buffered performic acid has far less solvent action and the P.F.A.B.-P.A.S. method, modified by the replacement of buffered for unbuffered performic acid, proved to be successful in the demonstration of two types of basophil cells in both rat and man.
THE LATEX SLIDE TEST IN RHEUMATIC DISORDERS
Authors: Wilson J. V. , Morison R. A. H. , Wright V. 
Published: June 2007

The latex slide test (L.S.T.) has been shown to be simple to perform and easy to read. It gives results comparable with the more complicated serological procedures used in the diagnosis of rheumatoid arthritis.In 603 cases the L.S.T. and differential agglutination test gave a high degree of correlation. There were only four discrepancies between the two tests. The L.S.T. is the more practicable for routine laboratory use.The L.S.T. has been correlated with the duration, activity, and extent of rheumatoid arthritis, and also with the erythrocyte sedimentation rate, haemoglobin level, and radiographic appearances. The various serological tests are tabulated.
SERUM HAPTOGLOBINS IN HAEMOLYTIC STATES
Authors: Owen J. A. , de Gruchy G. C. , Smith H. 
Published: June 2007

Serum haptoglobin levels have been studied in patients with a number of haemolytic disorders.In general, serum haptoglobins were low in patients with increased haemolysis. Values were reduced irrespective of whether haemolysis occurred intravascularly or extravascularly.The reduction was related to the amount of haemoglobin destroyed per day.Serum haptoglobins may be raised in certain neoplasms and infections and during adrenocortical steroid hormone therapy. A rise in haptoglobins due to one of these factors may mask a fall due to haemolysis. Thus a normal or raised serum haptoglobin does not necessarily exclude a haemolytic process.
The rate of blood loss from skin punctures during the Ivy bleeding time test
Authors: Willoughby M. L. N. , Allington M. J. 
Published: June 2007

The rate of blood loss from skin punctures during the performance of the Ivy bleeding time test has been measured by a simple technique in normal individuals, in patients without defects of the haemostatic or coagulation system, and in patients with known haemorrhagic disorders.A wide range was found in normal individuals, but repeated tests on a single individual showed a smaller variation. Nearly half of the tests on patients with von Willebrand's disease, thrombocytopenia, `capillary type' of bleeding, or haemorrhagic renal failure gave abnormally high rates of blood loss. Haemophilic, Christmas disease, and Dinedevan-treated patients gave low volumes and rates of blood loss.A group of patients has been encountered in whom the bleeding time was normal but the rate of blood loss was increased. The majority of these had haemorrhagic symptoms and other evidence of a defective haemostatic or coagulation system. It is suggested that a consideration of the rate of blood loss in those patients with a normal bleeding time gives additional help in interpreting the Ivy test. A high rate may indicate the need for further investigation of the haemostatic and coagulation system.
A sensitive method for the colorimetric determination of urea
Authors: Beale R. N. , Croft D. 
Published: June 2007

A method is described for the direct colorimetric determination of urea in biological fluids. The method depends on the reaction (first described by Wheatley, 1948) between urea, diacetylmonoxime, and phenylanthranilic acid in the presence of controlled amounts of oxidant; chloride ions are included to sensitize the reaction; manganous ions stabilize the resultant colour; and phosphate enables reasonable reproducibility to be achieved.The method is rapid and suitable for routine analytical purposes. Precision and accuracy are good; sensitivity is high for an activated acid reagent up to about one week old, and thereafter decreases.A hypothetical mechanism for colour formation is presented.
Laboratory studies with the systemic trichononacide, metronidazole
Authors: Jennison R. F. , Stenton P. , Watt Leslie 
Published: June 2007

Laboratory studies with the trichomonacidal agent, metronidazole, show that 66 strains ofT. vaginaliswere killed in three days by concentrations of 0·0625 μg./ml. to 1 μg./ml.Estimations of serum and urine levels in nine volunteers, the serum levels in 31 women, and the urine levels in 33 women show that metronidazole is rapidly absorbed and excreted in high concentration in the urine.Development of resistance to metronidazole byT. vaginalishas not been demonstrated eitherin vivoorin vitro.No toxic effect was demonstrated in the blood, liver, or kidney.
Lipids in cadaver sera after fatal heart attacks
Authors: Enticknap J. B. 
Published: June 2007

Blood lipids have been measured in sera from 750 cadavers. All nine fractions measured show a remarkably consistent pattern of differences between the various gross morbid anatomical forms of ischaemic heart disease. The highest mean values are found when an obvious coronary thrombus is present and those in simple atheromatous occlusion are nearly as high. When there is recognizable necrosis the values are considerably more normal.The serum lipids show relatively little change due to autolysis, about one half of 1% per hour or less.Lipoprotein levels assayed withCl.welchiialpha toxin correlate well with disease states.
Hereditary elliptocytic anaemia
Authors: Davidson R. J. L. , Strauss W. T. 
Published: June 2007

A sibship with four cases of hereditary elliptocytic anaemia is described. The condition in this family may have arisen as a mutation in the mother of the sibship; affected members were unable to taste phenylthiocarbamide while normal members were tasters.Experiments with32P-orthophosphatein vitrodid not show any evidence of biochemical upset as found in hereditary spherocytosis; thus a combination of congenital spherocytosis and elliptocytosis cannot be supported as the cause of the haemolytic state. Clinical evidence of haemolytic disease was accompanied by a tendency to excessive lysisin vitro.Infection may play a part in the precipitation of anaemic crises in this as in other hereditary haemolytic anaemias.
Sodium, potassium, water, and haemoglobin in the packed red cells of severe thalassaemia
Authors: Choremis C. , Economou-Mavrou Cleopatra , Tsenghi Christina 
Published: June 2007

Sodium, potassium, water, and the mean corpuscular haemoglobin concentration were determined in the packed erythrocytes of children with severe thalassaemia. The concentration of sodium in the packed red cells was higher than normal in a significant proportion of children with thalassaemia whereas potassium in the packed cells and sodium and potassium in the plasma were normal.On average, the cell water content was a little higher and the mean corpuscular haemoglobin concentration a little lower than normal.The cation concentrations in the packed cells of thalassaemia are compared with those in other anaemias. Similarities are pointed out between the sodium concentrations in the packed cells of thalassaemia and those from the foetus and children suffering from malnutrition.
Sarcoma of breast, with particular reference to its origin from fibroadenoma
Authors: Curran R. C. , Dodge O. G. 
Published: June 2007

Thirty-nine sarcomas of breast are described. The patients' ages ranged from 26 to 78 years but most patients were middle-aged or elderly. Evidence is adduced that 16 of the tumours arose from pre-existing fibroadenomas and others very probably did so. Many tumours were adenosarcomas and one was a carcinosarcoma which preserved its structure in a lymph-node metastasis. Recurrences were mostly local, but a small group had a much graver prognosis. A pleomorphic and giant-cell structure usually meant a high degree of malignancy but the significance of cartilaginous or bony metaplasia, present in seven tumours, was less certain.It is wise to regard all `fibroadenomas' of the breast occurring in patients over 40 years of age as at least potentially malignant, and these should be examined histologically with care, particularly since sarcomatous change may be present in one part only and therefore easily overlooked.
A colorimetric method for the determination of carboxyhaemoglobin over a wide range of concentrations
Authors: Trinder P. , Harper F. E. 
Published: June 2007

A colorimetric technique for the determination of carboxyhaemoglobin in blood is described. Carbon monoxide released from blood in a standard Conway unit reacts with palladous chloride/arsenomolybdate solution to produce a blue colour. Using 0·5 to 2 ml. of blood, the method will estimate carboxyhaemoglobin accurately at levels from 0·1% to 100% of total haemoglobin and in the presence of other abnormal pigments.A number of methods are available for the determination of carboxyhaemoglobin; none is accurate below a concentration of 1·5 g. carboxyhaemoglobin per 100 ml. but for most clinical purposes this is not important. For forensic purposes and occasionally in clinical use, an accurate determination of carboxyhaemoglobin below 750 mg. per 100 ml. may be required and no really satisfactory method is at present available. Some time ago when it was important to know whether a person who was found dead in a burning house had died before or after the fire had started, we became interested in developing a method which would determine accurately carboxyhaemoglobin at levels of 750 mg. per 100 ml.
Morphology and functional cytology of the small intestinal mucosa in malabsorptive disorders and other diseases
Authors: Fry Lionel , McMinn R. M. H. 
Published: June 2007

Small intestinal biopsies from 98 patients have been studied macroscopically, histologically, and histochemically, and the results correlated with laboratory and clinical observations. Neither a convoluted nor a flat mucosa can be considered diagnostic for any specific disease. A flat mucosa was found in one adult with intestinal Hodgkin's disease and in another following total gastrectomy.Histochemically all specimens from subjects with coeliac disease and idiopathic steatorrhoea showed a deficiency of succinic dehydrogenase in the epithelial cells, and the histochemical test for this enzyme, although not specific, may be a useful aid to diagnosis, since the degree of deficiency in these diseases was usually grosser than that in any other conditions. Other but variable enzyme deficiencies that may be present in these two diseases showed no correlation with the reduction of succinic dehydrogenase activity, nor was there any correlation between reduced enzyme activities and the severity or otherwise of the clinical features.A number of specimens from patients with conditions other than coeliac disease and idiopathic steatorrhoea that had a normal macroscopic appearance showed some reduction of intracellular enzyme activities histochemically. This was not so in the control group, and if these deficiencies can be confirmed biochemically, then histochemical tests may give an earlier indication of disordered function than macroscopical or routine histological examination.At present neither the macroscopic appearance nor any single histological or histochemical test on the biopsy specimen is diagnostic for a particular disease. These findings must be considered with the clinical details and results of other investigations in establishing a diagnosis.
Benign familial polycythaemia
Authors: Geary C. G. , Amos H. E. , MacIver J. E. 
Published: June 2007

An English family suffering from thalassaemia minor is described. Three generations are affected, and all the affected members had a considerably raised red cell count in the presence of slight or moderate anaemia, obviously abnormal peripheral films, and only slightly reduced M.C.H.C. values; and each had a moderately raised haemoglobin A2level, though foetal haemoglobin levels were normal.The presentation of a family with erythrocytosis recalls the condition described in the older literature as benign familial polycythaemia which was, in some cases at least, thalassaemia minor. It is suggested that the presence of a raised red cell count is a more reliable distinguishing feature than the presence of target cells, or the serum iron level, in thalassaemia minor.
Comparison of three simple methods for the assessment of `free' thyroid hormone
Authors: Gimlette T. M. D. 
Published: June 2007

A dialysis method for estimating `free' thyroxine is compared with two indirect methods using the uptake of triiodothyronine by the red cells and by a Sephadex column. The three methods give results which correlate well and the Sephadex method is the simplest.The theoretical basis of such tests and their role in the assessment of thyroid status is briefly discussed.
Seronegative glandular fever
Authors: Penman H. G. 
Published: June 2007

Seven sporadic cases of `seronegative glandular fever' have been examined in detail; five of the patients were adults aged more than 30, two were children. None showed evidence of `incomplete' or heat-labile sheep cell agglutinins, but in three very weak, though otherwise typical, glandular fever agglutinins were detected. Three of the other four showed evidence of certain infections, but these infections probably accounted for no more than a part of each illness.It is suggested that some, and possibly most, sporadic cases of seronegative glandular fever are of the same disease as seropositive cases, the patients' ages influencing the serological response. Certain conditions of known aetiology may, however, be clinically and haematologically indistinguishable from seronegative glandular fever.
Determination of uric acid levels in uraemia by enzymatic and colorimetric techniques
Authors: Howorth P. J. N. , Zilva Joan F. 
Published: June 2007

Serum uric acid levels were determined by specific and non-specific methods in uraemia in order to investigate the correlation between non-specific chromogen and serum urea level. The correlation was moderate and the magnitude of the non-specific chromogen was smaller than had been reported previously. The ratio [Formula: see text] urate was found to be 0·85 in both acute and chronic renal failure, a ratio very similar to that previously reported for normal and gouty subjects.In chronic renal failure the true uric acid level is correlated with urea level and there is a suggestion that serum uric acid levels in chronic renal failure are lower for a given urea value than in acute renal failure.
An automated method for serum bilirubin determination
Authors: Simmons N. A. 
Published: June 2007

A method for the determination of both direct and indirect serum bilirubin on the AutoAnalyzer is described which has a number of advantages over the automated method that is currently recommended. It gives total bilirubin results which are similar to those obtained with the equivalent manual method and direct bilirubin results which are usually about 10% lower.The effect of haemolysis on estimations was investigated. It has little influence on the total, but significantly lowers the direct bilirubin results.Simple methods for the preparation of true bilirubin standards and a stable control serum are described.
Trimethoprim: laboratory and clinical studies
Authors: Darrell J. H. , Garrod L. P. , Waterworth Pamela M. 
Published: June 2007

Trimethoprim is a synthetic compound which arrests the step in bacterial purine synthesis immediately succeeding that interfered with by sulphonamides.Acting alone it inhibits the growth of a wide range of bacteria in generally much lower concentrations than sulphonamides. Its action with a sulphonamide is strongly synergic and bactericidal.Studies are described of suitable cultural conditions, methods of testing sensitivity, and acquired resistance.Some clinical results of its use are reported in respiratory tract infections, Gram-negative septicaemia, and urinary tract infections, and further therapeutic possibilities are discussed.
Tubular reabsorption of calcium in normal and hypercalciuric subjects
Authors: Peacock M. , Nordin B. E. C. 
Published: June 2007

Tubular reabsorption and excretion of calcium were studied at different levels of filtered calcium by means of calcium infusion in normal and hypercalciuric subjects and in patients with idiopathic nephrolithiasis.Calcium reabsorption and excretion rose linearly with filtered load and in no case was a maximum tubular reabsorptive capacity for calcium reached.No decrease in tubular reabsorption of calcium was found in hypercalciuric as compared with normocalciuric subjects, and no difference in tubular reabsorption was found between patients with idiopathic nephrolithiasis and normal subjects.Calcium excretion and reabsorption calculated from the endogenous creatinine clearance during calcium infusion were virtually identical with the corresponding values calculated from the inulin clearance.