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J H Hageman

Publications and source records attributed to J H Hageman.

At least 37 records · Page 2Linked to original sources
PubMed1984

Single, chemically defined sporulation medium for Bacillus subtilis: growth, sporulation, and extracellular protease production.

The composition and application of a single, chemically defined medium or growth and sporulation of Bacillus subtilis is described. At 37 degrees C cells grew with a doubling time of about 40 min; cultures attained near-maximal spore formation (70 to 80% by 12 h after the end of exponential growth and produced 1 X 10(9) to 2 X 10(9) heat-resistant free spores at 24 h. Dipicolinic acid production was completed between 7 and 11 h. Cells grown in the single, chemically defined medium excreted levels of serine and neutral proteases comparable to those excreted in nutrient broth medium.

Bacillus subtilis↗
PubMed1983

Bilharzial portal hypertension.

Schistosomiasis is a major world health problem that is being encountered more frequently in North America as the immigration patterns from endemic areas change. At Henry Ford Hospital in Detroit, only two admissions for active schistosomiasis were recorded before 1970, but since then there have been 43 such cases. Of these 45 patients, six required seven portasystemic shunts, primarily to treat the complication of esophageal variceal hemorrhage, which is associated with portal hypertension secondary to presinusoidal hepatic fibrosis. No operative deaths occurred, and follow-up averaging 6.6 years revealed no late deaths and minimal encephalopathy. These excellent results are attributed to successful portal decompression and the well-preserved liver function that is typical of these patients. Bilharzial portal hypertension should be suspected in immigrants from endemic areas who have bleeding esophageal varices.

Africa↗
PubMed1983

Bacillopeptidase F: two forms of a glycoprotein serine protease from Bacillus subtilis 168.

Bacillopeptidase F is a serine endopeptidase excreted by Bacillus subtilis 168 after the end of exponential growth. As a step toward discovering a physiological function for this protease, an enzymological and immunological study was undertaken. When bacillopeptidase F was purified at pH 10, a number of enzymically active, rapidly moving electrophoretic forms were observed, as had been previously reported. Rabbit antiserum was prepared against one form. When the enzyme was purified at pH 6.0 in the presence of the covalent inhibitor phenylmethylsulfonyl fluoride, using the rabbit antiserum to detect the bacillopeptidase F protein, no fast-moving electrophoretic forms were observed. Instead, only two forms of the enzyme were isolated. One form had a molecular weight of 33,000, and the other had a molecular weight of 50,000, as determined by equilibrium sedimentation methods. Both forms appeared to be glycoproteins, both contained compounds, released on acid hydrolysis, which cochromatographed with phosphoserine and galactosamine, and the two gave identical immunoprecipitin lines in Ouchterlony double-diffusion tests. The smaller form had a pI of 4.4, whereas the larger had a pI of 5.4. The data suggest that bacillopeptidase F is distinct from all other proteases of B. subtilis.

Amino Acids↗
PubMed1983

Production by Bacillis subtilis of brown sporulation-associated pigments.

The mode of production of the brown pigments of Bacillus subtilis 168 L-4, pigments frequently used as phenotypic markers for sporulation in this organism, has been studied. A defined liquid medium which promoted maximal pigment formation was developed. Five brown components, which could be resolved by thin-layer chromatography, were produced in the culture broth. Removal of cells from the medium at the end of logarithmic growth did not alter the type or amount of the pigments formed, indicating that the cells excreted pigment precursors into the medium during growth. Pigment formation from the precursors was found to occur by an oxygen-requiring, base-dependent, Mn2+-requiring, nonenzymatic pathway. Pigment production was also stimulated by the presence of tyrosine and histidine in the medium. The increases in extracellular pH often associated with spore formation in B. subtilis might be the cause of the concomitant appearance of brown pigments.

Bacillus subtilis↗
PubMed1981

Induction of Bacillus subtilis sporulation by nucleosides: inosine appears to be sporogen.

Inosine completely reversed the selective inhibition of sporulation in Bacillus subtilis 168 caused bym-aminobenzeneboronic acid; guanosine and adenosine, but not xanthosine, partially reversed inhibition, whereas pyrimidine nucleosides were slightly effective. In addition, 0.005 to 0.025 mM inosine caused a four- to fivefold stimulation of sporulation of B. subtilis grown in minimal salts medium. Ultraviolet and infrared spectra and other physical and chemical properties of inosine were markedly similar to those of "sporogen," a previously described endogenous sporogenesis factor present in sporulating Bacillus species.

Adenine↗
PubMed1980

Arterial embolization: problems of source, multiplicity, recurrence, and delayed treatment.

The clinical course of 225 patients who had experienced 309 arterial embolic episodes was reviewed with special reference to the problems of the identification of the source of embolization, multiplicity of involvement, significance of recurrence, and the effects of some therapeutic means, including anticoagulation, on the early and late results. The most common source of embolization was cardiac (in 85% of the cases). Persistent search, at times by complex diagnostic methods, uncovered the origin in all but 11% of the cases. Within a range of 8 hours to 7 days the effect of delayed treatment had a linear relationship to the severity of ischemic changes and the deterioration of favorable results. Angiography was helpful and often essential in the diagnosis of visceral embolism and in differentiating local thrombosis from embolism in the periphery. Recurrent embolization was common (in 28% of the cases), was often multiple, and had a grave prognosis. Permanent anticoagulant therapy, preferably with but even without the removal of the source of embolization, reduced the rate of recurrence and, in general, reduced early and late morbidity and mortality rates.

Adult↗
PubMed1978

Benzeneboronic acid selectively inhibits sporulation of Bacillis subtilis.

m-Aminobenzeneboronic acid at levels of 0.2 mM in nutrient broth medium selectively inhibited sporulation without appreciably altering vegetative growth. Significant inhibitory effects were seen even when it was added as late as 6 h after the end of logarithmic growth. The pH changes associated with growth and sporulation of Bacillus subtilis in nutrient broth were not significantly altered by the inhibitor. When it was present in cultures of actively growing cells, its inhibitory effect could not be reversed by simple dilution. The compound caused extensive clumping, of cells, which appeared not to be related to the ability of boronates to esterify to diols.

Bacillus subtilis↗
PubMed1978

Spinal cord damage in surgery of the abdominal aorta.

The incidence, etiology, and clinical manifestations of spinal cord damage after abdominal aortic operations and abdominal aortography are defined on grounds of the authors' experience and of a survey of the pertinent literature. In the authors' experience the incidence of cord damage was 0.25% (three of 3,164) after abdominal aortic operations and 0.01% (two of 17,494) after abdominal aortography. As regards postoperative cord complications in the authors' series, they occurred only in cases of aneurysm, were 10 times more common in ruptured than in unruptured aneurysms, and the neurological loss usually was complete flaccid paraplegia (five of eight or 62%) with high mortality (three of eight or 38%), and rare partial (two of eight or 25%) or complete (one of eight or 13%) recovery. Recovery was more likely the lesser than neurological loss. The cause of postoperative spinal cord damage was ischemia resulting from the interruption of a critical radicular artery at the lower thoracic or high lumbar vertebral levels in the presence of anomalously located greater radicular or infrarenal radicular arteries. High aortic clamping and hypotension increased the probability of this occurrence, which essentially was unpredictable and, therefore, unavoidable. In postartographic cases the cord damage is more variable in its extent, and its cause is a chemical insult brought about by flooding the anterior spinal artery with contrast medium to which the patient probably is hypersensitive. In both groups treatment of the established clinical picture (paraplegia) is confined to support and rehabilitation.

Aged↗
PubMed1978

Aneurysms of the renal artery: problems of prognosis and surgical management.

The clinical course of 29 patients bearing 36 renal artery aneurysms was reviewed. The majority of the lesions (30 of 36 or 83%) were detected incidentally in the course of angiographic examination, mostly in the study of peripheral atherosclerotic arterial disease. Twenty-five lesions 2.0 cm or less in diameter, treated conservatively and observed during a period of time of from 1 to 17 years, remained clinically silent. In 10 patients (with 11 lesions) surgical treatment was employed. For eight patients the surgical treatment consisted of reconstructive excision and repair, with excellent results in all cases but one for a period of observation of from 1 to 17 years. In one patient aneurysmal dilatation of a vein bypass graft resulted in nephrectomy 2 years following operation. In the remaining two patients nephrectomy was required. Unless hypertension or pregnancy complicates the clinical picture, renal arterial aneurysms 1.5 cm or less in diameter can be observed safely by periodic angiography. Surgical repair of an aneurysm is recommended regardless of size if pregnancy cannot be avoided and hypertension is uncontrolled, and in aneurysms 1.5 cm or less in diameter which show an increase in size. A number of reconstructive vascular procedures have proved successful. Ex vivo repair may be an organ-saving technical aid.

Adult↗
PubMed1977

Translumbar aortography: a study of its safety and usefulness.

We reviewed that clinical courses of 14,550 patients in whom translumbar aortography was performed. The principal aim of the survey was to determine the incidence of major and fatal complications attributable to this diagnostic study, as an index of its safety. We found that in this group, seven major (0.05%) and two fatal (0.014%) complications occurred. The corresponding incidences for transfemoral catheter aortography reported in the literature were found to be 1.34% and 0.06%, respectively. Translumbar aortography, when performed under the proper indications and appropriate conditions, has a degree of safety equal to or greater than that of transfemoral catheter aortography, and its diagnostic reliability within its technical scope is high.

Aortic Aneurysm↗
PubMed1976

Congenital arteriovenous anomalies of the limbs.

Observations in 33 patients with congenital arteriovenous fistulas described ten years ago have been extended with the addition of 49 other cases; the clinical, pathologic, and roentgenographic characteristics of these lesions in the entire group of 82 patients have been summarized. The findings in the entire group over the additional observation period have confirmed the conclusions previously reached, namely, that (1) these clinically extremely varied lesions have a unitary (developmental) cause; (2) for rational management, angiographic investigation is indispensable to establish their extent and complexity; (3) with few exceptions, their radical cure by surgical means is impossible; and (4) the large majority of patients do well on a carefully supervised conservative regimen, with surgical intervention reserved for individually defined instances.

Angiography↗
PubMed1975

Use of N-benzoyl-L-tyrosine thiobenzyl ester as a protease substrate. Hydrolysis by alpha-chymotrypsin and subtilisin BPN.

In the course of searching for specific chromogenic substrates which might be useful in screening for protease-deficient mutants of Bacillus subtilis, we have developed a method for the synthesis of N-benzoyl-L-tyrosine thiobenzyl ester (BzTyrSBzl) in good yield. Spontaneous base hydrolysis of this thiol ester is low, but several serine proteases hydrolyze it readily. Spectrophotometric measurement of the hydrolysis of the ester in the presence of 5,5'-dithiobis(2-nitrobenzoic acid) provides a continuous assay for chymotrypsin as sensitive as any assay reported in the literature. Serine proteases which hydrolyze this substrate may be detected in polyacrylamide disc gels by incubation in the presence of nitro blue tetrazolium. Apparent Km values of 0.02 and 7 mM and kcat values of 37 S-1 and 126 S-1 were observed for the hydrolysis of BzTyrSBzl by alpha-chymotrypsin and subtilisin BPN', respectively. Additionally, 5 mM indole was observed to behave as a strict competitive inhibitor of the alpha-chymotrypsin-catalyzed hydrolysis of BzTyrSBzl but was observed to increase the maximal rate of hydrolysis of p-nitrophenyl acetate by alpha-chymotrypsin by 30%, as previously described. These data, the published data of other workers, and results from studies with molecular models of trypsin and subtilisin BPN' are used as the basis for describing more fully a secondary hydrophobic binding pocket on alpha-chymotrypsin. The pocket is immediately adjacent to the active site serine and is tentatively suggested to be composed of 4 aliphatic side chain residues and 2 glycine residues.

Benzyl Compounds↗