Identification of Tn2401, a transposon encoding multiresistance to aminoglycosides

A transposable element, Tn2401, was found in a clinical isolate of Pseudomonas aeruginosa. Tn2401 had a size of 7190 nucleotides and encoded aminoglycoside 3'-phosphotransferase and aminoglycoside 6'-N-acetyltransferase. The sequence encoding the former enzyme was homologous with that of Tn903. Pseudomonas aeruginosa strains harbouring this transposon were resistant to kanamycin, neomycin, lividomycin, ribostamycin, paromomycin, netilmycin, tobramycin, dibekacin, gentamicin, sisomicin, and butirosin.

Copper loss from the copper T model TCu22OC

The effect of mineral deposits on the copper dissolution rate of the Copper T Model TCu22OC was examined. 118 Copper T22OC devices removed from subjects for various medical and personal reasons after 12 to 72 months in utero were examined and graded based on the proportion of the total copper area covered with mineral deposits. The deposits increased in average size during the first three years of IUD use and then remained relatively constant. Seventeen percent of the devices were in situ for four or more years. Copper analysis was performed on 30 Copper T 22OC devices from selected periods of use : 12-14, 22-26, 36-39 and 48-72 months of use. The mean daily copper loss was 29.4 micrograms and the range, 7.3 to 62.1 micrograms. An inverse correlation between the amount of mineral deposit on the copper surface and the rate of copper loss was observed.

Site of action of a ribosomal RNA methylase conferring resistance to thiostrepton

A methylase enzyme, responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton. This RNA-pentose methylase modifies adenosine-1067 of Escherichia coli 23 S rRNA.

The effect of levonorgestrel and estrone rods on male reproductive function

The effect on spermatogenesis of the implantation of six rods containing levonorgestrel and three estrone rods was studied in seven volunteers aged 32-40, with normal pre-treatment spermiogram. None of the subjects achieved azoospermia. The lowest sperm count was below 1 million/ml in three subjects and below 12 million/ml in the other four. Plasma FSH and testosterone were severely depressed during the study, but LH was only transiently depressed for the first two months. Four subjects recovered pre-treatment sperm counts in spite of the FSH levels below 1.5 mIU/ml and testosterone levels below 1 ng/ml, which is contradictory to the current concept on hormonal regulation of spermatogenesis.

Comparative rheology of nucleated and non-nucleated red blood cells. II. Rheological properties of avian red cells suspensions in narrow capillaries

The flow properties of nucleated avian (duck) red cell suspensions were determined in narrow glass capillaries (internal diameter 5- 11 micrometer) perfused at constant pressure. Measurements were carried out of cellular and suspending fluid flow velocity of dynamic (tube) hematocrit. Comparison with previous measurements on human erythrocyte suspensions showed that the dynamic hematocrit reduction (Fahraeus effect) of avian cell suspensions was significantly more sensitive to changes of hematocrit than observed on the human cells. It was in addition found that the Fahraeus effect is the dominating phenomenon determining the viscosity of the nucleated cell suspensions, in contrast to suspensions of non-nucleated human red cells. Furthermore, the apparent viscosity of the nucleated cell suspensions is significantly higher than that of human blood at equal capillary diameter and tube hematocrit. In the living capillary bed of birds, the unfavourable rheological properties of the nucleated red cells could be compensated for by a low capillary hematocrit and/or a higher capillary density compared to mammalian species.

Comparative rheology of nucleated and non-nucleated red blood cells. I. Microrheology of avian erythrocytes during capillary flow

Deformation and dynamic flow behaviour of nucleated duck erythrocytes were compared to those of nonnucleated human cells during steady flow (at wall shear stresses up to 3 N.m-2) through glass capillaries (diameter between 5 micrometer and 12 micrometer). While the deformation process of both cell species is qualitatively similar, significant quantitative differences demonstrate a lower deformability of the nucleated erythrocytes. In comparison to human cells, the avian red cells exhibit significantly lower stability of orientation during capillary flow. Viscometric measurements show that, in contrast to human red cell suspensions, the relative viscosity of nucleated cell suspensions does not decrease with increasing suspending medium viscosity. The results indicate that the hydrodynamic disturbance caused by avian erythrocytes in the flow of the suspending fluid is more pronounced than that of the mammalian cells. This is due to their lower ability to adapt to local shear forces.

Sperm suppression with monthly injections of medroxyprogesterone acetate combined with testosterone enanthate at a high dose (500 mg)

The combination of an initial injection of 1000 mg of depot medroxyprogesterone acetate and 500 mg of testosterone enanthate, followed by monthly administration of 150 mg and 500 mg of the same drugs, was tested in 10 healthy males aged 28 through 39, with pre-treatment sperm counts of 50 x 10(6)/ml or more. Eight of the subjects achieved azoospermia, and the sperm counts of the other two declined 0.09 ad 5 million/ml. This last subject was highly refractory to treatment as his sperm density recovered to 27 million sperm/ml at the 6th month of continuous therapy. FSH was severely depressed during the entire treatment period. LH fell to 30--40% of normal values in the first two months and then showed a slow recovery during maintenance treatment. Testosterone measured one month after each injection was between 10 and 30% of pre-treatment values. Three of the subjects had increased libido and potency, none had decreased sexual drive or potency. All subjects gained weight with the average gain being 6 kg. The increase in the dose of testosterone enanthate to 500 mg/ng did not improve the results as compared to previous trials using lower doses of TE.

[Nuclear magnetic resonance tomography]

Imaging methods based on nuclear magnetic resonance allow the production of sectional images of the human body without ionizing radiation. It is possible to measure the density and relaxation times of the water protons in body fluids or tissue. This allows not only to obtain morphological information but also to get some insight into the spatial distribution of physiological data. Starting with a review of the principles of nuclear magnetic resonance it is explained how the measured signal can be associated with an image point; it is also explained what type of apparatus is necessary and what the physical limitations are. Possible risks the patient may be exposed to in an examination using nuclear magnetic resonance are discussed. The present state of the technical development enables the production of whole-body sectional images of a living person within about one minute. By means of some typical examples the nature and properties of these images are explained. Although extensive clinical studies will be necessary before a more general assessment can be made of this method, an outlook is provided on expected further developments and possible future fields of application.

[Lymphography in testicular tumors]

In 45 patients with tumours of the testes (5 seminomas, 40 nonseminomas) the pretherapeutic lymphographic diagnosis could be histologically tested after a retroperitoneal removal of lymph nodes. The lymphographic security was more than 82%, 4 diagnoses each were falsely positive and falsely negative. The sensitivity was 81%, the specifity 83%. With these results the lymphography meets the requirements which are made upon a diagnostic method. It shall be relevant to therapy. An increase of the security by additional examinations (tomography and cavography) is possible. Taking into consideration its limits the bipedal lymphography belongs to the obligatory spread diagnosis in tumours of the testes, its results allow an estimation of the spread of the tumour, the therapeutic effect and the prognosis of the tumour disease.

Molecular nature of a streptomycin and sulfonamide resistance plasmid (pBP1) prevalent in clinical Escherichia coli strains and integration of an ampicillin resistance transposon (TnA)

A small, nonconjugative plasmid, designated pBP1, was originally found in different fecal Escherichia coli serotypes isolated from a healthy proband. Of a total number of 130 hospital strains of E. coli subsequently studied, 8.5% yielded plasmid of the pBP1 type. This R plasmid specifies resistance to streptomycin (Sm) and sulfonamides (Su) and has a mass of 4.0 megadaltons. Inactivation of streptomycin is due to the aminoglycoside phosphotransferase APH-(3 "). A physical map was constructed by analysis with restriction endonucleases. Another small plasmid, pBP1-1, was isolated from one of the hospital strains and characterized as an enlarged pBP1 replicon containing an additional deoxyribonucleic acid sequence identified as a transposable element for ampicillin resistance (TnA). Plasmid pBP1-1 was cleaved by restriction enzymes for identification of the transposon sequence which codes for a TEM 1 beta-lactamase. The sequence organizations in the Sm Su plasmids RSF1010 and pBP1 were shown to be identical for regions specifying streptomycin and sulfonamide resistance, but different for the region containing the origin of replication and genes for replicative functions. Thus, RSF1010, which has been considered as the prototype of Sm Su plasmids, and pBP1, which is at least as frequent in clinical isolates as RSF1010, do not have a single common ancestor.

Subdermal implants of different steroidal compounds for treatment of endocrinological disorders

Various types of steroid-containing implants were used in the treatment of benign prostatic hypertrophy, congestive prostatitis, and hypogonadism. 2 Silastic capsules, each containing 22-23 mg of ethinyl estradiol, were inserted subcutaneously in 5 men with benign prostatic hypertrophy. A decline in testosterone levels to less than 1 ng/ml was attained within 6 months following insertion. 6-8 Silastic capsules containing 21-23 mg each of testosterone were implanted in 15 men: 2 castrates and 13 hypogonadals. Testosterone levels increased initially, reaching the highest level at 3 months. Thereafter, the testosterone concentrations declined but remained slightly above pretreatment levels at 9 months. In a group of 9 subjects, 7 men with hypogonadism and 2 women with hypernephroma were treated with 2 rods, each containing approximately 200 mg testosterone propionate. Testosterone concentrations showed initial rises but did not remain elevated. 12 male subjects, 6 with congestive prostatis and 6 with benign prostatic hypertrophy, were treated with a combination of 3 levonorgestrel rods and 3 estrone rods. Each rod contained 40 mg of steroid. This regimen had a therapeutic effect but was only partially successful in inhibiting spermatogenesis.

[Secondary testicular tumors as sole metastases. Discussion of the metastatic pathways]

The authors present two cases of secondary unilateral testicle tumours which are found very infrequently. They discuss the possible metatasic approaches with special emphasis on the lymphatic way since, even when the other ways are possible, the anatomical conditions of the testis make them more theoretical than real.

Elevated plasma and urinary guanosine 3':5'-monophosphate and increased production rate in patients with neoplastic diseases

The plasma and 24-hr urinary levels of cyclic adenosine 3':5'-monophosphate and of cyclic guanosine 3':5'-monophosphate (cGMP) were determined for 19 healthy normal patients, 54 patients with six types of nonneoplastic diseases (cholelithiasis, peptic ulcer, coronary heart disease, hypertension, regional ileitis, and cirrhosis), and 54 patients with five types of neoplastic disease (cancers of the lung, colon, and breast, acute myelocyte leukemia, and Hodgkin's disease). The cyclic adenosine 3':5'-monophosphate levels of urine and plasma in normal subjects, in noncancer subjects, and in cancer subjects did not differ significantly. The cGMP levels in the noncancer group were similarly unchanged from those in the normal group. However, mean cGMP levels in the urine and plasma of patients with neoplastic diseases were, respectively, 2- and 3-fold greater than the normal values (p less than 0.005 for urine and p less than 0.05 for plasma). Pharmacokinetic studies with [3H]cGMP in nine healthy controls and 15 patients with neoplasia showed that the mean production rate of this nucleotide in patients with metastatic cancer was elevated when compared to normal patients, but many values fell within the normal range. In acute leukemia, the production rate was seven times normal, with four of five patients having values clearly outside the normal range. The plasma clearance rate in patients with neoplasia was not decreased when compared to that in normal patients. It is proposed that an increased production rate, rather than any change in plasma clearance, accounts for the increased levels of cGMP in the plasma and urine of some patients with neoplastic disease.

[Results obtained from staining lymphography, using carbon with lipoidal suspension, in cases of female genital carcinoma (author's transl)]

Reported in this paper is the use of a carbon-lipoidal suspension for presurgical staining lymphography which was applied to carcinomata colli uteri and corporis uteri. The suspension could not be prepared until permission had been obtained from the National Drug Expert Committee. Better colour contrast representation of the femoral and iliacal lymph nodes during the operation was thus achieved, and, consequently, surgical radicality was substantively improved. The approach proved less expensive and tedious than previous methods used for colour representation of lymph nodes in the minor pelvis. The dye used did not cause any complications. The advantages of the method are discussed. General application seems to be commendable, following further testing.

[Health damage by means of forced smoking]

Forced smoking (= passive smoking) is not only a molestation but a real health risk for nonsmokers. The reasons for this are given in detail by a survey of results of the world literature. The main reasons are: In tobacco smoke are more than 40 cancerogenic substances which show a clear summative effect in contrast to other poisons. Avoidable cancerogens therefore must be eliminated from our environment wherever it is possible. There is no reason to make an exception with tobacco smoke. Special attention is to be paid to more than a dozen of cancerogenic nitrosamines in tobacco smoke. The content of nitrosamines in sidestream-smoke is up to fifty times higher than in the main stream of the tobacco smoke. Tobacco smoke therefore is the most important source of nitrosamines in our environment at all. The cancerogenic effect of passive smoking is secured in animal experiments unobjectionably. Passive smoking is the most important cause of bronchitis and pneumonia in early childhood and favours inflammations of the respiratory tract in older children and in animal experiments, etc.

Characterization of a naturally occurring R plasmid in Salmonella isangi conferring unusually high resistance to ampicillin

A strain of Salmonella isangi was isolated from HUMANA milk, used a baby food in Bulgarian hospitals. It harbours two stable plasmids, distinguishable by their molecular weight of 21 Mdal for the transfer factor (rRB 1) and 9,3 Mdal for R-factor rRB 2, confering resistance to ampicillin, cephalothin, streptomycin and sulfonamides. Both plasmids are maintained in different copy numbers per chromosome genome equivalent, 8 copies for rRB 1 and 158 copies for rRB 2, associated with an unusual high level of resistance to ampicillin (MIC 65 mg/ml).

[Comparison of the value of ERCP, angiography and scintigraphy in pancreatic diseases]

The endoscopic retrograde cholangiopancreaticography, angiography and scintigraphy have a different value in the diagnostics of chronic pancreatitis and carcinoma of the pancreas. The scintigraphy of pancreas has the lowest value. It should not alone be the basis for making the diagnosis or planning the treatment. In chronic pancreatitis the endoscopic retrograde cholangiopancreaticography has precedence of angiography. The chronic pancreatitis may angiographically be recognised only in the late phase. However, the angiography can give valuable references to the planning of the operation. At a suspicion of the pancreas malignoma the endoscopic retrograde cholangiopancreaticography and the angiography have nearly the same value in the plan of diagnostics and they both should be performed.

Tyramine kinetics and metabolism in cirrhosis

Hypertyraminemia is common in hepatic cirrhosis and correlates in severity with encephalopathy. The mechanism of cirrhotic hypertyraminemia has not been established. The alternative possibilities are increased production from tyrosine and impaired degradation by monoamine oxidase. This investigation determined the pharmacokinetics of tyramine after an intravenous bolus injections of [3H]-tyramine (180--200 muCi 12 Ci/mmol sp act) in 13 cirrhotics and 9 controls. In normals, [3H]tyramine levels initially declined rapidly (alpha-phase) followed by a slower decline (beta-phase) with an average t 1/2 of 20.8 min. Average normal metabolic clearance rate and production rate were 13.2 liters/min and 15.4 microgram/min, respectively. In cirrhotic patients, the plasma disappearance curve for [3H]tyramine was qualitatively similar to that of the control subjects with no apparent different in beta-t 1/2 (17.2 min). The hypertyraminemia of cirrhosis resulted primarily from overproduction of tyramine, as the production rate (32.0 microgram/min) in these patients was significantly greater (P less than 0.05) than in controls, whereas the metabolic clearance rate remained normal (average 12.2 liters/min). A difference in ratio of tyramine metabolic products was noted as well. Cirrhotics had a high ratio of plasma 4-hydroxyphenylethanol:4-hydroxyphenylacetic acid (60:40 vs. 30:70) as compared with normals. Although the tyramine clearance rates are similar in normals and cirrhotics, different mechanisms may be responsible for catabolism.

[Value of lymphography within the framework of complex diagnosis of fever of unknown origin]

After comprehensive diagnostics on account of antibiotic-resistant subfebrile temperatures under suspicion of a lymphogranulomatosis a lymphography was performed in a 49-year-old patient. The lymphographic findings are discussed in detail. Since these findings differential-diagnostically allow a tuberculosis of the lymph nodes, a tuberculostatic therapy is performed. 6 months later the patient has an improved general condition and may again work in this former profession.

[Smoking ban at the workplace--the order of the hour (author's transl)]

Smoking is by far the most important inhalation noxa at the workplace and is probably to be considered most harmful to the workers generally during working hours. Tobacco smoking at the workplace also endangers the health of non-smokers through passive smoking. From this it is deduced that a general ban on smoking at the workplace is to be considered the order of the hour and as the most important aim of occupational medicine and industrial legislation at the present time.

The isolation of IS1 and IS2 DNA

DNA of the IS-elements IS1 and IS2 was prepared by digestion of appropriate heteroduplex molecules with endonuclease S1, followed by sucrose gradient centrifugation or gel electrophoresis. The material obtained is homogeneous with regard to size. The length of IS1 DNA is 820 +/- 65 nucleotides, the length of IS2 DNA is 1,350 +/- 70 nucleotides. IS1 DNA is not cleaved by the restriction endonucleases Eco R1, Hind II or Hind III. IS2 DNA is cleaved once by each of the two latter enzymes. The buoyand density determined by equilibrium centrifugation of Hg-complexes in Cs2so4 corresponds to a GC content of approximately 50%. Labelling with polynucleotide kinase indicates that both IS DNA's have a guanosyl residue at both of their 5'-termini.