Control of the initiation of sporulation in Bacillus subtilis by a phosphorelay

Sporulation in Bacillus subtilis is a developmental process induced as a response to nutritional stress. Activation of sporulation-specific gene transcription is under the control of the spoOA gene product. The SpoOA protein and the SpoOF protein are both homologous to response regulator proteins of two-component regulatory systems which control bacterial responses to a variety of environmental challenges. Response regulators are activated by specific kinases which phosphorylate them. In this study, it was shown that phosphorylation of SpoOA occurs via a phosphotransferase which is the product of the spoOB locus. The phosphodonor in this reaction is the phosphorylated form of SpoOF. It is postulated that SpoOF acts as a secondary messenger that can be phosphorylated by a variety of kinases depending on the particular environmental stress. The series of phosphate transfer reactions in this system is called a phosphorelay. The end product of this series of reactions is SpoOA approximately P which is shown to have greater affinity for the DNA target, the OA box, of SpoOA on the abrB promoter than the unphosphorylated form. SpoOA approximately P, but not SpoOA, was shown to be an activator of transcription of the spoIIA operon which codes for the sporulation-specific sigma factor sigma F. Thus, the initiation of sporulation is dependent on SpoOA approximately P which arises through the phosphorelay and which acts as a transcription factor to repress certain genes, e.g. abrB, and activate others, e.g. spoIIA.

A prion protein variant in a family with the telencephalic form of Gerstmann-Sträussler-Scheinker syndrome

We present a patient with a mutation in the open reading frame of the prion protein gene (PRNP), which results in substitution of valine for alanine at codon 117. The patient is a member of a large American kindred of German descent with the telencephalic form of Gerstmann-Sträussler-Scheinker syndrome (GSS). Two other affected members of this kindred carried this mutation, as inferred from haplotypes of their offspring and spouses. The mutation was absent in one member with a protracted neurologic illness that differed from the other affected members' illnesses. The identification of a distinct PRNP mutation in the telencephalic form of GSS supports the hypothesis that allelic forms of PRNP may correspond to distinct clinical disease entities.

A new efficient NanoTip lead

The ideal lead has low, stable acute and chronic thresholds, high pacing impedance, and good sensing. Leads with low, stable thresholds have been developed, but pacing impedance has been in the 600 omega region. One way to increase pacing impedance is to decrease the electrode's surface area. The threshold performance and sensing ability of less than 5 mm2 electrodes have been considered questionable, up to now. We have developed a 1.5 mm2 porous, platinized, steroid-eluting electrode and have demonstrated in canine studies that it has excellent performance. Chronic thresholds are low at about 0.65 +/- 0.28 V (ventricular) and 0.42 +/- 0.12 V (atrial) at 0.5 msec. Chronic pacing impedance is in the 1200-1300 omega region, but mean chronic R and P wave source impedance is less than or equal to 1500 omega. Sensing is excellent, with almost double the P wave amplitudes usually measured in the canine.

Circadian characteristics of dialyzable and non-dialyzable human urinary electrolytes, trace elements and total solids

Seven clinically-healthy men ranging in age from 21 to 25 years participated in this study. Urine samples were collected at 3 hr intervals over a single 24 hr span. Urines were pooled by using 20% of the total volume collected from each subject over a 3 hr collection span. The resulting 8 pools were analyzed for pH, specific gravity, osmolality, urea N, creatine, uric acid, glucose, phosphorus, chlorides, sodium, potassium, calcium, magnesium, silicon, aluminum, zinc and total solids. Each of the 8 pools was serially dialyzed at pH 7.35 against ammonium-barbituric acid buffer. The non-dialyzable portions were then re-analyzed for the remaining solids, sodium, potassium, calcium, magnesium, silicon, aluminum and zinc. Aliquots of the non-dialyzable fraction were examined by high performance liquid chromatography. Up to twelve discernable fractions were observed in each 3 hr urine by monitoring ultraviolet light absorbance at 280 nm wavelength. Range of change throughout the 24 hr (lowest to highest value) for most variables was 100% or more. In the eight 3 hr pooled urine samples, statistically-significant circadian variation could be described for volume, pH, osmolality, urea nitrogen, creatinine, uric acid, glucose, phosphorus, chlorides, for five of eight non-dialyzed (total) components (Na, K, Ca, Si and solids) and for five of twelve non-dialyzable solid fractions, as well as for total non-dialyzable solids. Single cosinor analysis resulted in description of a significant circadian rhythm in osmolality, urea nitrogen, creatinine, glucose, phosphorus, chlorides, total Na, K, Si and solids; non-dialyzable Si and solids; dialyzable Na, K, Si and solids; and for total solids, as well as their fractions at 23.4 and 25.9 min. These observations are furnished in order to further document the extreme circadian rhythmicity in all aspects of kidney function and as reference for future work which uses any of the investigated urinary endpoints whose circadian time structure is herein described.

Effect of heparin and heparin fractions on experimental abscess formation

To evaluate the effectiveness of heparin and heparin fractions in decreasing abscess formation, rats were divided into six groups. A fibrin clot containing 10(9) live Escherichia coli was placed in the peritoneal cavity of each rat. Group 1 (controls) received daily subcutaneous (SQ) injections of 0.1 mL of saline solution. Group 2 received daily intramuscular injections of gentamicin, 12.5 mg/kg. Group 3 received a daily SQ dose of 30 U of porcine heparin. In addition to gentamicin, group 4 received heparin, group 5 received heparin fraction PK10169, and group 6 received heparin fraction CY216, all in daily SQ doses of 30 U. Survivors were killed at ten days and examined for intra-abdominal abscesses. All group 1 animals developed abscesses. Abscess formation was significantly decreased in all groups receiving gentamicin. When used with gentamicin, neither heparin nor heparin fractions decreased the number of abscesses formed when compared with gentamicin alone. Heparin or heparin fractions in combination with gentamicin did decrease abscess size significantly when compared with controls.

Deaths in early childhood in west Cumbria

Investigation of deaths in early childhood is one method of assessing the quality of child care in a district. This paper describes a study carried out in one health district, on children in the age group one week to five years: 28 deaths occurred over a two-year period, 25 of these in the first year of life. The deaths are classified according to potential preventable factors. The study gave a more detailed picture of mortality patterns in the district than was previously available. Parents found the home interview in the study helpful in allowing them to explore their worries about the child's death.

Natural history of autoimmune thyroiditis

One hundred and sixty-three asymptomatic people with thyroid antibodies or raised serum thyrotrophin (TSH) concentrations, or both, and 209 age-matched and sex-matched controls without either marker of thyroid disorder were followed up for four years to determine the natural history of autoimmune thyroiditis. Mildly raised TSH concentrations alone and the presence of thyroid antibodies alone did not significantly increase the risk of developing overt hypothyroidism during the four years compared with the controls. Overt hypothyroidism developed at the rate of 5% a year in women who initially had both raised TSH concentrations and thyroid antibodies. Prophylactic treatment with thyroxine may be justified in women found to have both markers of impending thyroid failure. The cost effectiveness of screening the adult population remains to be evaluated.

Malignant myelosclerosis. Myeloproliferative disorder or leukemia?

Four patients with the picture of "malignant myelosclerosis" are described and the relationship of this condition to acute granulocytic leukemia is discussed. It is suggested that there is a leukemic process from the beginning, that the fibrosis of the marrow is reactive rather than neoplastic, and that the disease should not be regarded as an accelerated form of chronic (primary) myelosclerosis. The presence of excessive reticulin in the marrow in acute leukemia, especially when the patient is first seen, indicates a bad prognosis and poor response to chemotherapy. A systemic fungal infection in one patient is described.

Practolol-induced autoantibodies and their relation to oculo-cutaneous complications

Tissue auto-antibodies were investigated in fifty-one patients (twenty-five female, twenty-six male) receiving practolol for ischaemic heart disease or dysrhythmias and compared with those found in 204 patients (fifty-eight female, 146 male) with ischaemic heart disease who did not receive practolol. Antinuclear factor (ANF) was found in 24% female and 16% male patients receiving practolol, but only in 5% of female and 4% of male patients who were not taking practolol. Thyroid cytoplasmic antibody (TCA) was detected in 16% female and 20% of male patients receiving practolol, compared to 10% of females and 6% of males in the control group. The incidence of ANF and TCA was significantly higher (P less than 0-05) in patients receiving practolol compared to the control group. The occurrence of gastric parietal cell antibody (PCA) and smooth muscle antibody (SMA) was not associated with practolol therapy (odds ratio of 2-4 and 1-9 respectively). The incidence of skin and eye complications was found to be 10% and the female to male ratio of this complication was 4 : 1. The correlation between autoantibody production and oculo-cutaneous complications could not be established in such a small group but three of the patients with the complications were found to have PCA, although PCA was found not to be associated with practolol therapy. Four of the five patients with the complications did not have circulating ANF.

Gastric histology and its relation to anaemia in the elderly

During 1 year 725 consecutive patients admitted to a geriatric unit were investigated for anaemia. 51% of men had haemoglobin levels below 13.5 g/dl and 41% of women had levels below 12 g/dl. 657 patients had an azuresin tubeless test meal following an augmented dose of histamine acid phosphate and 450 (68%) had achlorhydria. Gastric biopsies were performed on 240 of the patients with achloryhdria and 201 satisfactory biopsies were obtained. These were graded into five categories: (1) normal; (2) surface gastritis; (3) diffuse gastritis; (4) chronic atrophic gastritis, and (5) chronic atrophic gastritis with intestinal metaplasia. The grades of mucosal change could not be correlated with the presence or absence of anaemia, the state of gastric function as measured by the Schilling test for absorption of vitamin B12, or the level of vitamin B12 in the serum.

A long-term follow up of patients with autoimmune thyroid disease

A survey in a general practice in the North-East of England in 1963 detected thyroglobulin antibodies in 16.2% of women and 4.3% of men. High titres of antibodies were found in 4.6% of women and 1.6% of men. Forty six subjects with thyroglobulin antibodies (from an original total of fifty-two) were studied in 1972 and forty of these were studied further in 1975. These subjects were compared with a group of age- and sex-matched controls from the original survey. Three of the subjects had developed overt hypothyroidism by 1975 and a raised serum thyroid-stimulating hormone (TSH) concentration was found more frequently in euthyroid subjects peviously found to be antibody positive. There was a striking difference in the antibody studies in that only 26% of the previously antibody positive subjects had thyroglobulin antibodies in 1972 and 30% in 1975. A raised serum TSH concentration was found to correlate with cytoplasmic a-tibodies and particularly with the combination of cytoplasmic and thyroglobulin antibodies.

Idiopathic arterial calcification in infancy

Two cases of idiopathic generalized arterial calcification in infancy are described. The changes in the vessels consist of calcification in relation to the internal elastic lamina, with secondary subintimal proliferation of fibrous tissue and, occasionally, extension into the media. They are usually most marked in the coronary arteries, with resulting myocardial disease, and acute congestive cardiac failure is the most common presentation and cause of death. The histological picture resembles closely the arterial changes that may occur in severe renal disease, hyperparathyroidism, primary bone disease, hypervitaminosis D, and occasional cases of congenital heart disease.

Acute haemolytic anaemia associated with polyagglutinability of red cells

A 7-week-old albino infant developed acute haemolytic anaemia following an operation for strangulated inguinal hernia. This was considered to be due to polyagglutinability of the red cells, the haemolysis subsiding as the cells returned to normal. The red cell changes were shown to be due to activation of T-antigen, reacting with anti-T in the adult blood transfused to the infant.

Evaluation of a tanned red cell technique for thyroid microsomal antibodies

A haemagglutination test for thyroid microsomal (cytoplasmic) antibodies, using formolized tanned sheep red cells, is described and evaluated. The technique is essentially similar to the thyroglobulin tanned red cell test. It has been shown to be more sensitive and easier to use than the complement-fixation test. A combined screening test to detect both thyroglobulin and microsomal antibodies is described.

Grades of hypothyroidism

Seventy-nine patients with hypothyroidism and autoimmune thyroid disease were studied, and allotted to one of four categories on the basis of clinical and biochemical features. Firstly, patients with overt hypothyroidism had obvious clinical features of hypothyroidism and abnormal results from routine tests of thyroid function. Secondly, those with mild hypothyroidism, however, had minor and non-specific symptoms, but the routine measurements of circulating thyroid hormone concentration generally lay within the normal range, although they were significantly lower than those seen in subclinical hypothyroidism or in normal subjects. The serum concentration of thyroid-stimulating hormone (TSH) was raised in this group and their symptoms resolve with treatment. Thirdly, patients with subclinical hypothyroidism were asymptomatic, had a raised serum TSH concentration, but all other measurements of thyroid function are indistinguishable from those recorded in people with autoimmune thyroid disease without disturbance of thyroid function and in normal subjects. Lastly, subjects with circulating thyroid antibodies, normal indices of thyroid function, and a normal serum TSH concentration were indistinguishable biochemically from normal subjects.Thus hypothyroidism is a graded phenomenon, the most valuable features for defining the individual grade being the clinical manifestations, the serum TSH concentration, and the presence of circulating antibodies to thyroid tissue.

Grades of hypothyroidism

Seventy-nine patients with hypothyroidism and autoimmune thyroid disease were studied, and allotted to one of four categories on the basis of clinical and biochemical features. Firstly, patients with overt hypothyroidism had obvious clinical features of hypothyroidism and abnormal results from routine tests of thyroid function. Secondly, those with mild hypothyroidism, however, had minor and non-specific symptoms, but the routine measurements of circulating thyroid hormone concentration generally lay within the normal range, although they were significantly lower than those seen in subclinical hypothyroidism or in normal subjects. The serum concentration of thyroid-stimulating hormone (TSH) was raised in this group and their symptoms resolve with treatment. Thirdly, patients with subclinical hypothyroidism were asymptomatic, had a raised serum TSH concentration, but all other measurements of thyroid function are indistinguishable from those recorded in people with autoimmune thyroid disease without disturbance of thyroid function and in normal subjects. Lastly, subjects with circulating thyroid antibodies, normal indices of thyroid function, and a normal serum TSH concentration were indistinguishable biochemically from normal subjects.Thus hypothyroidism is a graded phenomenon, the most valuable features for defining the individual grade being the clinical manifestations, the serum TSH concentration, and the presence of circulating antibodies to thyroid tissue.

Pathological changes in virus infections of the lower respiratory tract in children

The pathological changes are described in 22 children with proven or suspected virus infection of the lower respiratory tract. Two main patterns of disease were found: acute bronchiolitis and interstitial pneumonia. Particular viruses were not specifically associated with particular histological changes. The prime importance of the respiratory syncytial virus (RSV) as a cause of disease and death in young infants is again shown. Structural lesions and clinical dysfunction correlate fairly well; in acute bronchiolitis the main lesion is epithelial necrosis when a dense plug is formed in the bronchiolar lumen leading to trapping air and other mechanical interference with ventilation: in interstitial pneumonia there is widespread inflammation and necrosis of lung parenchyma, and severe lesions of the bronchial and bronchiolar mucosa as well. The implications of these structural changes for clinical management are discussed. The possibility of a hypersensitivity reaction in the cot death syndrome is raised, mediated by a serum antibody-antigen-complement reaction.

Salmonella typhimurium pericarditis

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