Plasma fibronectin, von Willebrand factor antigen, and blood rheology. Association with diabetic microvascular disease

Plasma fibronectin might play a role in the pathogenesis and progression of diabetic microvascular disease. To test this hypothesis we measured plasma fibronectin, von Willebrand factor antigen, fibrinogen, erythrocyte filtrability, whole-blood viscosity, proteinuria and albuminuria in 25 control subjects and 29 diabetic patients with and without microvascular complications. Plasma fibronectin was significantly higher in the diabetic patients, especially in those with retinopathy and nephropathy. A significant correlation between fibronectin and von Willebrand factor antigen was found in both patients with and without microangiopathy (p less than 0.001). In diabetic patients with and without microvascular complications, several significant correlations were found between increased fibronectin levels and reduced erythrocyte filtrability (p less than 0.001) and between the increase of fibronectin and whole-blood viscosity (p less than 0.001). Furthermore, a significant correlation was found between plasma fibronectin levels, proteinuria (p less than 0.001) and albuminuria (p less than 0.001). The relationship between plasma fibronectin and changes of blood rheology may be important for the occurrence and progression of diabetic microangiopathy.

Characterization of the spo0A locus and its deduced product

The highly pleiotropic stage 0 sporulation locus of Bacillus subtilis, spo0A, has been cloned in bacteriophage lambda, subcloned in plasmids, and sequenced. The locus was found to code for a protein of 29,691 Da. Analysis of the in vivo transcripts from this region by nuclease S1 protection experiments located the start and stop of transcription of the locus. The transcription start site was preceded by a promoter resembling sigma 37-dependent promoters. Two mutations originally assigned to a second locus, spo0C, in this region because of their weakly pleiotropic phenotypes were cloned and sequenced. The mutations were found to be different missense alterations in the same base of the 10th codon preceding the carboxyl end of the Spo0A protein. These results, along with the finding that mutations in the spo0A gene product [Hoch, J. A., Trach, K., Kawamura, F. & Saito, H. (1985) J. Bacteriol. 161, 552-555] suppress the requirement for spo0B, spo0E, and spo0F gene products in transcription from sigma 28-dependent promoters, suggest that the Spo0A protein interacts directly with the transcription machinery to effect the initiation of sporulation. The deduced amino acid sequence of the Spo0A protein was highly related to that of the OmpR regulatory protein of Escherichia coli.

[Evaluation of the comparative relationship between HbA1 and HbA1c in subjects with OGTT type diabetes and in normal subjects]

The authors investigated if significantly high glycosylated hemoglobin and glycosylated hemoglobin c levels are present in patients with impaired glucose tolerance tested with oral glucose tolerance test. The patients with impaired glucose tolerance presented higher, but non significantly, glycosylated hemoglobin levels then normal subjects.

Demonstration of rabies viral antigen in paraffin tissue sections: comparison of the immunofluorescence technique with the unlabeled antibody enzyme method

The immunofluorescence technique and the peroxidase-antiperoxidase method were used to demonstrate rabies antigen in a retrospective study on formalin-fixed, paraffin-embedded brain tissues from 34 naturally infected wild and domestic animals. Rabies was confirmed with immunofluorescent staining on fresh brain tissue at the time of necropsy of the animals. There was a perfect correlation (serial sections from a given brain area were always positive by both methods), but the peroxidase-antiperoxidase technique was preferred, since no trypsin digestion was required. Twenty six of the 34 animals were immunohistochemically positive and had encephalitis, and in 21 of these 26, the hematoxylin and eosin-stained sections contained detectable intracytoplasmic inclusion bodies in at least 1 brain area. Of the remaining 8 animals (with no inflammatory lesions), 7 were positive for rabies antigen and 2 had no inclusion bodies. Rabies antigen was apparent in 62% of the brain areas in which inclusion bodies were not found in the corresponding hematoxylin and eosin stained sections. Thus, together with the inclusion body positive areas, which were all immunohistochemically positive, it was possible to diagnose rabies in a total 84% of the areas examined. Both techniques greatly facilitate the diagnosis of rabies and may be a reliable help to the diagnostic pathologist when only formalin-fixed tissues are available. However, the methods should not be considered substitutes for the immunofluorescence technique and the mouse inoculation test with fresh brain tissue.

Cloning of the neutral protease gene of Bacillus subtilis and the use of the cloned gene to create an in vitro-derived deletion mutation

The neutral protease gene of Bacillus subtilis has been cloned, and its nucleotide sequence has been determined. The cloned gene was used to create an in vitro-derived deletion mutation, which was used to replace the wild-type copy of the gene. This deletion, in combination with a deletion of the alkaline protease gene, completely abolished protease production. The loss of the proteases had no detectable effect on growth, morphology, or sporulation.

Replacement of the Bacillus subtilis subtilisin structural gene with an In vitro-derived deletion mutation

The entire subtilisin structural gene from Bacillus subtilis I168 has been cloned, and its nucleotide sequence has been determined. When expressed on a high-copy-number shuttle vector, a fivefold increase in serine protease activity was observed. The DNA sequence of the gene is 80% homologous to the Bacillus amyloliquefaciens subtilisin structural gene, and the translated mature coding sequence is 85% homologous to the published protein sequence of subtilisin BPN'. The chloramphenicol resistance determinant of a plasmid integrated at the subtilisin locus was mapped by PBS1 transduction and was found to be linked to glyB (83%) and argC (60%), but not with metC or purB . The chromosomal locus containing the wild-type subtilisin allele was replaced with an in vitro-derived allele of the gene (delta apr-684) that contained a 684-base-pair deletion. The technique used for introducing the deletion is a variation of the gene replacement methods used in Saccharomyces cerevisiae and Escherichia coli. When used in B. subtilis, deletion mutants could be directly screened among the transformants. Physiological characterization of the delta apr-684 mutation revealed no discernable effect on the formation of heat-resistant endospores, but strains carrying the mutation produced only 10% of wild-type serine protease activity. A model is presented that outlines the pathway for plasmid integration and deletion formation in B. subtilis.

Reduced triiodothyronine content in liver but not pituitary of the uremic rat model: demonstration of changes compatible with thyroid hormone deficiency in liver only

Intracellular thyroid hormone concentration and action were examined in the liver and the pituitary of a nephrectomized rat model (Nx); the results were compared with those obtained from control (C), thyroidectomized (Tx), and nephrectomized-thyroidectomized (NxTx) littermates. Based on the severity of the uremia, Nx rats were subdivided into Nx1 and Nx2 groups; the former included rats with serum urea nitrogen of less than 100 mg/dl and the latter rats with serum urea nitrogen greater than 100 mg/dl. A group of rats pair-fed to the Nx rats was also included (PF). In the liver, nuclear T3 content (picograms per g liver) and T3-receptor binding capacity (Cmax, picograms T3 per mg DNA) were measured. The respective results from all groups of rats were as follows (asterisks denote values differing from C with a P value less than 0.05): C, 308 +/- (SE) 45 and 121 +/- 11; Nx1, 245 +/- 43 and 85 +/- 15; Nx2, 163 +/- 19 and 74 +/- 7; Tx, 43 +/- 11 and 91 +/- 10; NxTx, 33 +/- 10 and 54 +/- 6; and PF, 237 +/- 20 and 121 +/- 9. T3 receptor binding affinity (Ka), ranging from 3.62-5.28 X 10(9) M-1, was not significantly different among the six groups of rats. In the pituitary, T3 content (picograms per mg pituitary) was reduced only in the Tx rats, being 3.13 +/- 0.89 as compared to 7.04 +/- 1.48 in the C rats (P less than 0.05). In the Nx1, Nx2, and PF rats, pituitary T3 contents were 9.81 +/- 3.22, 13.01 +/- 3.60, and 7.83 +/- 1.08, respectively, and were not different from the C rats. Serum TSH was reciprocally elevated only in the Tx rats. The reduction in hepatic nuclear T3 content and T3-Cmax in the Nx2 rats is consistent with the presence of selective tissue deficiency of thyroid hormone. This is in agreement with the observation of reduced activity of two liver enzymes known to be under thyroid hormone regulation. The pituitary, however, had normal T3 content, suggesting a dissociation in thyroid hormone-dependent metabolic status between a peripheral tissue (liver) and the pituitary. This explains the failure to observe an increase in the serum TSH level, a manifestation of reduced intracellular rather than serum T3 concentration. Decreased food intake appeared not to be the cause of thyroid hormone abnormalities observed in uremia, as PF rats failed to manifest the changes found in Nx rats.

Cloning, sequencing, and secretion of Bacillus amyloliquefaciens subtilisin in Bacillus subtilis

The subtilisin gene from B. amyloliquefaciens has been cloned and expressed under its own promoter on a high copy plasmid, pBS42, in Bacillus subtilis I-168 (Marburg strain). Greater than 95 percent of the expressed protease activity is secreted, and the activity is sensitive to inhibition by phenylmethylsulfonyl fluoride as expected for subtilisin. Bacillus subtilis transformants carrying the Bacillus amyloliquefaciens subtilisin gene in pBS42 (called pS4) secreted large amounts of a protein not seen in control pBS42 transformants. This protein migrated in SDS gels near the position of authentic subtilisin. The complete nucleotide sequence of the cloned gene has been determined using dideoxy sequencing methods. Ba131 exonuclease digestion studies at the 5' end of the gene have defined a 31 base pair stretch necessary for efficient expression of subtilisin. In addition to this putative promoter region, sequences have been assigned for ribosome binding, translation initiation, a signal peptide, the mature enzyme, and translation and transcription termination. A most interesting feature of the gene is a sequence of unknown function coding for roughly 75 amino acids between the signal sequence and the mature enzyme. It is proposed that this region serve as a pro-peptide as is commonly found in eukaryotic secreted proteases.

Changes of biological rhythms in primary headache syndromes

The circadian periodicity of some endocrine (PRL, cortisol, GH) and vegetative (oral temperature, blood pressure) functions has been studied in cluster headache, common migraine, atypical facial pain, and "mixed" headache. Changes in several biological rhythms have been found not only in cluster headache (CH) but also in other kinds of headache. Although a great individual variability of rhythometric changes has been observed, particularly in CH, the dysrhythmic condition seems to be more evident in chronic than in episodic CH. The clinical and chronobiological effects of lithium administration and of a short-term sleep deprivation have been studied in CH.

Chronobiological aspects of headache syndromes due to sellar or pituitary pathology

A chronobiological study was carried out in headache syndromes due to empty sella or to pituitary G.H.- and PRL-secreting adenomas. In the empty sella syndrome only the chrono-organization of G.H. secretion was disturbed, whereas pl. PRL exhibited the usual circadian pattern. The circadian rhythms of pl. G.H. and pl. PRL were abolished in G.H.- and PRL-secreting pituitary tumors, respectively, and were again detectable when patients were cured by selective transsphenoidal adenomectomy. A normal circadian rhythmicity of pl. cortisol was demonstrable in the empty sella syndrome and in pituitary adenomas, both before and after surgery.

Cloning structural gene sacB, which codes for exoenzyme levansucrase of Bacillus subtilis: expression of the gene in Escherichia coli

A clone bearing the structural gene sacB, coding for the exoenzyme levansucrase, was isolated from a library of Bacillus subtilis DNA that was cloned in phage lambda charon 4A on the basis of the transforming activity of the chimeric DNA. This lambda clone also was found to contain the sacR and smo loci. Subcloning the sacB-sacR region in plasmid pBR325 resulted in a clone which directed levansucrase synthesis in Escherichia coli. The nucleotide sequence coding for the secreted protein was localized on the physical map of the cloned DNA.

Hypoglycemic treatments and the fibrinolytic system in maturity-onset diabetes mellitus without thromboembolic manifestations

The fibrinolytic system was investigated in 115 patients with maturity-onset diabetes mellitus in good metabolic control and without thromboembolic manifestations. The patients were divided into 7 groups according to the hypoglycemic therapy: diet alone, tolbutamide, glibenclamide, phenformin, combination of the last two drugs, insulin, combination of insulin and phenformin. Our results indicate that in maturity-onset diabetes both fibrinolytic activity and inhibitors of fibrinolysis are increased. The enhanced fibrinolytic activity was not affected by different hypoglycemic drugs, whereas the main antiplasmins showed wide variations in the different treatment groups. In particular, a significant reduction of alpha 2M was observed in patients on glibenclamide therapy. In conclusion, our study showed that the high fibrinolytic state seems to be a constant element in diabetes, and that the different behaviors of the fibrinolytic system, reported by various authors in patients taking different hypoglycemic drugs, could be explained by the wide range of plasmin inhibitor levels observed in these conditions.

Ophthalmic herpes zoster with contralateral hemiparesis: a case report

Herpes zoster of the ophthalmic division of the left fifth cranial nerve with contralateral hemiparesis was observed in a 30-year-old man. Left carotid angiography showed segmental constrictions consistent with cerebral arteritis, possibly provoked by direct viral infection along the intracranial part of the ophthalmic nerve. An ischaemic lesion revealed by computed tomographic scan was considered secondary to arteritis and responsible for the hemiparesis. The presence of an immune response within the blood-CSF barrier was suggested by an increase of oligoclonal CSF IgG and IgA.

Molecular cloning of the spo0B sporulation locus in bacteriophage lambda

The stage 0 sporulation locus spo0B has been mapped by transformation between the pheA and spoIVF loci. Analysis of the behavior of alleles of the spo0B locus in trpE26 merodiploid strains indicates that all of the known alleles of this locus comprise a single complementation group. The spoIVF88 mutation was found to reside in a separate complementation group. The chromosomal region surrounding and including the spo0B locus was cloned in the lambda vector Charon 4A. Extensive restriction endonuclease analyses of the inserts in these phage revealed that an EcoRI fragment of DNA of 2.3 kilobases had transforming activity for spo0B mutations. Examination of the physical and genetic maps of the locus suggested that the entire spo0B locus is contained within this fragment. Subcloning of restriction endonuclease fragments of the lambda inserts and transformation analyses allowed assignment of surrounding genetic loci to specific DNA fragments.

Chromosomal location of a Bacillus subtilis DNA fragment uniquely transcribed by sigma-28-containing RNA polymerase

A fragment of the Bacillus subtilis chromosome containing a gene whose transcription is dependent on sigma-28-containing RNA polymerase has been genetically mapped by means of an integrable plasmid. This gene resides on the chromosome adjacent to the stage 0 sporulation locus spo0E between metC and citL. The gene was insertionally inactivated by cloning an internal EcoRI-HindIII fragment in the integrable plasmid pJH101 and by inserting the plasmid into the chromosome by transformation. Transformants bearing an inactivated gene were indifferent to this inactivation for both growth and sporulation.

Cloning and localization of the lepidopteran protoxin gene of Bacillus thuringiensis subsp. kurstaki

Bacillus thuringiensis subsp. kurstaki produces a proteinaceous crystalline inclusion that is toxic for lepidopteran larvae. There are several size classes of plasmids in this organism and the presence of one or more has been correlated with production of this protein, defined as a protoxin. DNA fragments of B. thuringiensis subsp. kurstaki, obtained by EcoRI digestion, were cloned into the vector Charon 4A. Recombinant phage were screened immunologically for the production of protoxin. Cells infected with one phage, C4K6c, produced antigen that was the same size as the protoxin and was toxic to Manduca sexta larvae. A 4.6-kilobase-pair (kbp) EcoRI fragment from C4K6c was subcloned into pBR328 and in both orientations in pHV33. Both Escherichia coli and Bacillus subtilis containing these recombinant plasmids produced antigen that crossreacted with antibody directed against the protoxin. The various sized plasmids of B. thuringiensis were purified and only an EcoRI fragment from the 45-kbp plasmid hybridized to phage C4K6c. One of the pHV33 subclones, pSM36, hybridized to the same size EcoRI/HindIII restriction fragments from plasmid or chromosomal DNA. The cloned EcoRI fragment contained a 0.9-kbp Pvu II fragment that was also present in chromosomal but not in plasmid digests. The original clone was therefore of chromosomal origin, although very similar or identical protoxin genes were present in both the 45-kbp plasmid and the chromosome. Several acrystalliferous nontoxic mutants have been isolated that lacked the 45-kbp plasmid and in some cases all plasmids. All of the mutants contained the chromosomal gene but did not produce protoxin antigen.

Adrenocortical responsiveness to the synthetic ACTH 1-17 analogue given at different circadian stages

The study concerns the adrenocortical glucocorticoid responsiveness to the ACTH 1-17 analogue given at different times of the day, namely near to the zenith and the nadir of the circadian curve of plasma cortisol. Two schedules of administration of the heptadecapeptide have been performed: a pulse i.v. injection of 4 microgram; b. i.m. injection of 100 microgram. Both the doses were given to the same subject in the morning and in the evening of different days. The chrono-sensitivity of the adrenal cortex to ACTH 1.17 analogue is well evident after pulse stimulation by a micro-dose of the heptadecapeptide; in fact the plasma cortisol increase from basal values is significantly higher in evening than in the morning (p less than 0.001). The cortico-stimulatory effect of the higher dose of ACTH 1.17 analogue lasts about 12 h. and then plasma and urinary glucocorticoids take the usual circadian pattern again.

Chronobiological study of pituitary adenomas and of the empty sella syndrome

A chronobiological study was carried out in pituitary GH- and PRL-secreting adenomas and in the empty sella syndrome. The circadian rhythms of plasma GH and plasma PRL were abolished respectively in GH- and PRL-secreting pituitary tumors, and they were again detectable after selective transsphenoidal adenomectomy. In the empty sella syndrome only the chrono-organization of GH secretion was disturbed, whereas plasma PRL exhibited the usual circadian pattern. A normal circadian rhythmicity of plasma cortisol was demonstrable in the 3 groups of patients. The diagnostic significance of the chronobiological findings obtained is discussed.

Neuroendocrinological aspects of depression and symptomatological picture

Cortisol and prolactin circadian rhythms were determined in a group of depressed hospitalized women who were submitted the next day to the dexamethasone suppression test. The depressed were classified as endogenous and non-endogenous according to symptomatological criteria. Some significant differences were found between the two groups when compared to control subjects in cortisol as well as prolactin biorhythms, and the cortisol suppression percentages were significantly lower in the endogenous than in the non-endogenous. This difference is abolished by benzodiazepine treatment.

Hypoglycemic therapy and hemostasis in maturity- onset diabetes mellitus: existence of an early prethrombotic state

We studied 115 patients with uncomplicated maturity-onset diabetes mellitus, 55 males and 60 females; patients were divided into 7 groups according to the hypoglycemic therapy (diet alone, tolbutamide, glibenclamide, phenformin, combination of the last two drugs, insulin, combination of insulin and phenformin). All patients were tested for a prethrombotic state by the simultaneous determination of the following parameters: ADP-induced platelet aggregation, Factor VIII as antigen and procoagulant activity and the plasma levels of fibrinogen and antithrobin III. Our results show that these parameters were markedly altered in diabetic patients when compared to apparently normal subjects of the same age; on the contrary, differences between groups of diabetic patients were very slight and hardly ever statistically significant. These results suggest that the prethrombotic alterations of hemostatic system are very similar in all groups of diabetic patients; this is true also for patients submitted to diet alone, i.e. with slight and usually recent-onset diabetes mellitus. In conclusion, our study suggests the opportunity, at least from the theoretical point of view, of systematic antiaggregant and/or anticoagulant treatment(s) in maturity-onset diabetes mellitus, whose severe and precocious prethrombotic alterations seem to be independent of the hypoglycemic treatment applied.

Enhanced antithrombotic mechanisms in patients with maturity-onset diabetes mellitus without thromboembolic complications

Some haemostatic parameters have been evaluated in a group of rigorously selected patients with maturity-onset diabetes mellitus without thromboembolic complications and in apparently normal subjects of the same age before and after the venous occlusion test (VOT). In basal conditions diabetics had higher levels of AT III as biological activity and higher fibrinolytic and antifibrinolytic activities than controls. After VOT, F VIII R:Ag increased significantly in both groups, more markedly in controls than in diabetics, while F VIII: C showed no modification. Also AT III R:Ag increased after the test, but such variation was significant only in diabetics; on the contrary, the biological activity of AT III was always significantly decreased after the test. After VOT there were also in both groups highly significant increases in the fibrinolytic and antifibrinolytic activities. Finally, HbA1c levels directly correlated with AT III as biological activity before VOT, but with no other parameter either before or after the test. These data suggest the existence in patients with diabetes mellitus without thromboembolic complications of an activated protective mechanism against intravascular clotting.

[The transmission of tick-borne encephalitis in Switzerland. An attempt at establishing a register of natural reservoirs for a seroepidemiologic examination of forest personnel in the middle of the country]

The aim of this investigation was to localize natural foci of tickborne encephalitis (TBE) in Switzerland by means of two approaches. (1) Sera of foresters, who are particularly exposed to TBE, were examined, restricting serum collection to the Plateau between the Lake of Constance and the Lake of Geneva. (2) Virus isolations were performed on 8600 ticks (Ixodes ricinus) collected all over the country. In four regions natural foci of varying size were detected: (1) in the northern parts of the Canton of Zurich in conjunction with the southern parts of the Canton of Schaffhausen, (2) in the region of Horgen on the Lake of Zurich, (3) in the region of Thoune, and (4) in the marshy region situated between the Lakes of Neuchâtel, Bienne and Morat. The morbidity rate in foresters varied from 0-5%, and rose to 12-16% in regions with a known concentration of natural foci. The infection rates in ticks average 0.1%, but, depending on the regions where ticks were collected, maximum rates of 1% were attained.

Isolation of Bacillus subtilis genes from a charon 4A library

A library of Bacillus subtilis chromosomal deoxyribonucleic acid (DNA) was constructed, using lambda charon 4A as a cloning vector. Partially cleaved Bacillus subtilis DNA was prepared by partial methylation with EcoRI methylase, followed by complete EcoRI endonuclease digestion. More than 95% of the phage particles carried B. subtilis DNA inserts. When this library was screened for transforming activity, using competent cells, 70% of the genetic markers tested were found in a sample of 1,710 plaques. Cloned genetic loci were found to be about 100-fold more efficient in transforming activity than chromosomal DNA. Intact phage particles containing the pheA locus were found to be able to transform competent recipients with approximately the same efficiency as phage DNA. Transformation by intact particles was insensitive to deoxyribonuclease.

Mosaicism for an extra small ring chromosome

A new case for mosaicism for an extra small ring chromosome is described in a 13-year-old girl with minimal phenotype anomalies and moderate mental retardation. The origin of the extra chromosome could not be determined either cytogenetically or clinically. The present case is compared with six similar cases in the literature.

Mutants of Bacillus subtilis affected in spore outgrowth

Six mutants of Bacillus subtilis 168 that are temperature-sensitive in spore outgrowth were isolated. The outgrowth process proceeds normally at 35 degrees C, but at the non-permissive temperature (47 degrees C) it is arrested at a specific stage characteristic for each mutant strain. The mutants are not altered in vegetative growth whether at 35 degrees C or at 47 degrees C. They were characterized for their ability to synthesize RNA, proteins and DNA during outgrowth. A mutant defective in spore germination was also isolated; less than 5% of its spores can germinate at any of the temperatures tested. The mutations were mapped by means of transduction and transformation. The isolation of a number of outgrowth mutants which map at different loci and which affect outgrowth at different times is discussed in relation to the regulation of this process.

Studies on the Prethrombotic State of Patients with Maturity-Onset Diabetes Mellitus Undergoing Different Hypoglycemic Treatments

Different haemostatic parameters were investigated in 115 patients aeed 50-65 (55 males and 60 females) with maturity-onset diabetes mellitus and in 20 apparently normal control subjects. The patients were divided into 7 groups according to the hypoglycemic therapy.

VIII R:AC, fibrinogen, C1-INH and fibrinolytic activity of euglobulin precipitate were constantly increased in all groups of patients when compared to controls. AT III levels were always decreased. Plasma fibrinolytic activity and α1-Achy were almost never significantly different from controls. Other parameters did not show uniform behaviours in the different groups of patients, na~ely: ADP-induced platelet ageregation, VIII R:AC/VIII:C ratio, α2-M, I-α.-T.I. and α1.-P.I. levels.

If alterations in ADP-indfrced platelet aggregation, VIII R:AC/VIII:C ratio, fibrinogen and AT III are to be considered as index of hypercoa= gulability, the thrombotic risk of the patients was quite considerable when compared to that of controls, but no significant difference seemed to exist among the groups of patients.

Effect of 6-(p-hydroxyphenylazo)-uracil on the homologous and heterologous transduction processes in Bacillus subtilis

We have studied the effect of 6-(p-hydroxyphenylazo)-uracil on the recombination processes that operate in the homologous and heterologous transduction mediated by PBS1 and SP10 phages of Bacillus subtilis. The results obtained demonstrate that the process of heterologous genetic exchange is sensitive to this compound, whereas the homologous process is not. The present data, along with those of our previous work (U. Canosi, A. G. Siccardi, A. Falaschi, and G. Mazza, J. Bacteriol. 126:108--121, 1976), suggest that the DNA polymerase III is involved in the recombination process that operates in transformation and heterologous transduction, whereas homologous transduction follows a partially independent pathway not involving this protein.

Studies on transduction process by SPP1 phage

The conditions for optimal transduction efficiency of the Bacillus subtilis phage SPP1 have been investigated. By irradiating transducing lysates with u.v. light we have been able to obtain a fivefold increase in the number of transductants and to reduce strongly the interference caused by infective particles. Any dependence of SPP1 transduction on PBSX induction has been ruled out by the use of xin mutants, which are unable to induce the defective phage. SPP1 mediated transduction is susceptible to the restriction and modification system of B. subtilis. The rec functions involved in the recombination of the SPP1 transduced DNA fragment are probably identical to those required in DNA transformation and heterologous PBS1 transduction.

X chromosomes attached by their long arm: replication autonomy of the short arm adjacent to the inactive centromere

A 16 years old girl with Turner syndrome was found to have a 45,X/46,X,t(XqXq)?(q27q23) constitution. The two X chromosomes are attached by their long arms with loss of chromosome material and have one active and one inactive centromere. Analysis of replication patterns with autoradiography and BrdU treatment showed that the abnormal X is always the late replicating one and that the short arm of the second X which is adjacent to the inactive centromere maintains a degree of replication autonomy from the rest of the long arm.

Host cell reactivation of Bacillus subtilis bacteriophages

Host cell reactivation of ultraviolet-irradiated phage can be used as a probe of the bacterial repair system and to determine phage and cellular contributions to the repair process. Using the Bacillus subtilis phages SPP1, SP01, phie, and phi29, we found that the uvr-1 and polA functions are involved in the host cell reactivation of the four phages. SPP1 was the only phage whose reactivation was also decreased in recA, recD, and recF mutant cells. We studied variations of host cell reactivation for SPP1 during spore outgrowth; at high ultraviolet doses the activity of a spore repair system requiring deoxyribonucleic acid polymerase I became evident. The spore repair system was completely replaced by the vegetative one by 120 min of outgrowth.

[Effects of a vagolytic substance on the circadian rhythm of the ACTH-secreting system in man]

The circadian rhythm of plasma cortisol and urinary 17-hydroxy-corticosteroids has been studied in 6 normal volunteers both in basal conditions and after the administration of a single dose of 30 mg of a banthine derivative (the beta methyl-beta-isopropylaminoethyl ester bromide of xantene-9-carbonic acid, "Pervagal") given orally once a day at different hours (midnight, 4 AM, 8 AM, noon, 4 PM, 8 PM). The vagolytic drug inhibits the cortisol secretion only when administered at 4 PM, 8 PM or midnight, whereas it is ineffective when given at different hours. If don't exist circadian variations of the bio-availability of the drug employed, our results suggest that also in human beings as well as in experimental animals, the cholinergic mechanisms are effective, over all if not exclusively, in starting the circadian activation of the hypothalamo-pituitary-adrenal system.

Identification of thiobacilli by replica plating on thallous sulfide paper

Colonies of Thiobacillus thioparus and T. thiooxidans grown on thiosulfate medium can be identified by replica plating on thallous sulfide paper.

Sheehan's syndrome with complete bone marrow aplasia: long-term results of substitution therapy with hormones

A case of Sheehan's syndrome with pancytopenia and bone marrow aplasia is presented. The diagnosis was made 6 years after an ante-partum haemorrhage. The presenting feature was an anaemia unresponsive to usual therapy. Hormonal therapy alone (cortisone and thyroid extract with triiodothyronin, oestrogen and progestogen given sequentially) produced full haematological recovery, which has continued for 2 years since the treatment was begun.

Genetic and enzymic studies on the recombination process in Bacillus subtilis

We have isolated recombination deficient mutants of Bacillus subtilis on the basis of their sensitivity to methyl-methane-sulfonate or ultraviolet light, or of their inability to be transformed on solid medium. We have analyzed the mutants for several recombination and repair properties; we have grouped them in 5 classes on the basis of their phenotype and tested them for the activity of several enzymes acting on DNA, ie. DNA polymerase, polynucleotide ligase, ATP dependent DNase, and a DNase acting on single-stranded DNA. One mutant was found reduced in the latter DNase. Some of the mutants have been mapped, and they correspond to three different genes denominated rec D, rec F and rec G. All the recombination deficient mutants of B. subtilis described in the literature have been grouped in 7 classes; the mutations belong to 13 (and possibly 15) different genes distributed along the map. A coherent nomenclature and the criteria for a standard study of the rec mutants are proposed.