Direct Cord Reading Medium for Isolation of Mycobacteria

A study of growth and colony morphology of mycobacteria was performed on 7H10 medium and compared with the same medium to which WR 1339 was added. Collection strains of human, bovine, and atypical mycobacteria, in addition to 1,199 sputa, were planted on both media. The results showed that WR 1339 modifies the growth and colony morphology of human, bovine, atypical group I, and, to a lesser degree, atypical groups II, III, and IV mycobacteria. The great majority of human and bovine strains exhibit definite cords when examined at a magnification of 100 times. The colonies are larger when WR 1339 is added, especially if there is a small number of colonies. The addition of WR 1339 spreads the growth on the surface of the agar, producing a thin but larger colony as compared with 7H10 medium alone on which the colonies grow more vertically, thus producing thick but smaller colonies. WR 1339 spreads the growth, producing thin and transparent colonies where the cords are oriented in uniplane and easily visible directly on the isolation media. Half of the positive sputum cultures were easily identified at 12 days. The presence of typical cords permits a quick screening diagnosis of species directly on the isolation media and, in most instances, elimination of the possibility of atypical or contaminating colonies.     

Kurze Mitteilungen

Zusammenfassung Ein Paar Türkentauben brütete vom 29. 1. bis 15. 2. 1966 auf einem Straßenbaum in Berlin-Tempelhof. Es wurde nur ein Ei gelegt. Nach 17 Tagen schlüpfte das gelbbedaunte Junge. Es ist dann kurz danach, wahrscheinlich beim Umherkriechen auf dem Nestrand, erfroren. Die Umstände, unter denen die Brut erfolgte, waren äußerst ungünstig. Die Temperatur lag seit dem 7. 2. 1966 dauernd unter Null (–9 und –13 Grad). Die brütende Taube hatte von Anfang an auf dem Nestrand brüten müssen, da die Mulde schon vor der Eiablage völlig mit Schnee bedeckt war. Der brütende Vogel war mehrere Tage und Nächte von einem hohen Schneewall umgeben, der sich auf dem Nest gebildet hatte. Dieses Nest wurde von Mai 1964 an viermal von einem Türkentaubenpaar zum Brüten benutzt. Es wird vermutet, daß zum mindesten der eine Partner, der Tauber, während der ganzen Zeit derselbe geblieben ist.     

Use of hospital services by homeless families in an inner London health district.

Over the past decade the number of families in London who were considered officially to be homeless appreciably increased. In response to this many families have been given temporary accommodation, usually in bed and breakfast hotels, while awaiting permanent rehousing. About 200 of the roughly 600 hotels in London that provide such accommodation are located in the area of the former Paddington and North Kensington Health Authority, now part of Parkside Health Authority. The use made by the homeless population of hospital services was studied by finding out the numbers of inpatients admitted to hospital and the numbers presenting to the walk in paediatric clinic and the casualty department at one hospital. These figures were compared with those for local residents and the overall workload. The bed and breakfast population were high users of inpatient beds, the casualty department, and the paediatric clinic. Overall, about one tenth of the beds were used by these people. The health authority receives no additional funding for this group of patients. Further research is needed to find out if the high use of hospital services made by these patients reflects their increased morbidity or their inability to obtain primary care services.     

Evaluation of the cervical cytology screening programme in an inner city health district.

District health authorities have been instructed to operate a cervical cytology call and recall screening programme using the age-sex registers held by family practitioner committees. A detailed evaluation of implementation in an inner London district showed that 477 out of 687 (69%) invitation letters sent to women by the family practitioner committee were either inaccurate or inappropriate: almost half of the recorded addresses were incorrect and a further fifth of the women were not eligible for a test. Overall, 90 women had a smear, which is only 13% of the total but 43% of those found to be eligible. The findings did not differ significantly with age. The findings have major implications not only for the effectiveness of call and recall for screening for cervical cancer but also for the future development of screening for breast cancer in such areas.     

Glutamate dehydrogenase activity in normal and vitrified plants of Agave tequilana Weber propagated in vitro

Agave tequilana stem explants were used to produce adventitious shoots under a set of different water potentials induced by different concentrations of gelrite in the medium. At high water potentials all shoots were vitrified; as the medium water potential became more negative the degree of vitrification decreased but the number of shoots per explant also diminished. The enzymes NADH and NAD-GDH (EC. 1.4.1.2) were measured along the water potential gradient. GDH activity was high in the non-vitrified tissues and decreased significantly in the vitrified ones.Abbreviations GDH glutamate dehydrogenase - MS Murashige and Skoog medium - MSO methionine sulfoximine - PVP polyvinylpolypyrrolidone - GS glutamine synthetase - GOGAT glutamine: oxoglutarate amino transferase     

A simple and reliable turbidimetric and kinetic assay for alpha-amylase that is readily applied to culture supernatants and cell extracts

Summary A simple, reliable and sensitive assay for alpha-amylase activity is reported, together with its theoretical derivation, that overcomes many of the problems encountered with other assays, especially when attempting to assay alpha-amylase activity in crude cell extracts or culture supernatants. The method relies on the reduction in turbidity that occurs upon digestion of a starch suspension with alpha-amylase. The initial rate of decrease in turbidity is shown to be proportional to a wide range of enzyme concentrations, permitting a rapid spectrophotometric and kinetic determination of alpha-amylase activity.     

Growing tobacco cells respond to rapid medium changes with a transient increase in localized Ca2+ activity

Summary A suspension of tobacco cells,Nicotiana tabacum L. BY-2, was subjected to a rapid change of medium, resulting in disturbance of growth. A subpopulation of growing cells responded to such a nutritional signal by establishing a transient, localized Ca²⁺ accumulation, as judged by chlorotetracycline fluorescence. Residing near or at the plasma membrane, this initial Ca²⁺ signal began to relax after 1 h to a value presumably corresponding to an equilibrium Ca²⁺ level. This response was susceptible to treatment with brefeldin A, an agent impacting vesicular traffic, as indicated by a further increase in fluorescence. By contrast, undisturbed growing and non-growing cells did not display a Ca²⁺ response, regardless of the presence of brefeldin A.     

Membrane receptors for estrogen,progesterone, and testosterone in the rat brain: Fantasy or reality

Summary 1. There are numerous circumstantial evidence supporting the concept that steroid hormones control cellular function by means other than the nuclear receptor steroid binding mechanism. It is the intent of this report to present evidence indicating that steroids bind to specific sites in neuronal membranes.2. Some of the criteria to define steroid membrane receptors using steroid-BSA conjugates that can be radioiodinated to desired specific activity have been fulfilled for each of the three sex steroids using crude synaptosomal membrane preparations (P2 fractions) from the CNS of female and male rats. Ligand binding for each of the three steroids indicate high-affinity and high-capacity sites with distinct brain selectivity and stereospecificity. For example, 17-E-6-[¹²⁵I]BSA binds hypothalamic P2 fractions (HYP-P2) with an estimatedK _d of about 3±0.7 nM (X ± SE;n=3), whereas the cerebellum P2 (CB-P2) fractions bind the ligand with aK _d of 34±7 nM and, aB _max of 3 and 42 pmol/mg protein, respectively. Estrogen and testosterone binding fit best a one-single site, while progesterone binding sites can be best represented by a two-binding site, one high-affinity (K _d=1–2 nM) and one low affinity (K _d=62 nM), in CB-P2 fractions from intact adult female rat brain. Kinetics studies for T-3-[¹²⁵I]BSA indicate that the estimatedK _d of 30±2 nM for the olfactory bulb P2 fractions (OB-P2) from male rats is in good agreement withK _d values computed from Scatchard-derived data using the LIGAND algorithm.3. 17-E-6-[¹²⁵I]BSA binding sites are stereospecific and appears to be present as early as 5 days of age in both the OB- and the CB-P2 fractions without changes during development. In contrast, P-6-[¹²⁵I]BSA binding sites are practically absent during days 5 and 12 and appear by day 22.4. Finally, membrane receptor molecules for estrogen and progesterone have been isolated and purified by affinity chromatography and characterized by PAGE and Western blot. Microsequencing of one of the membrane estrogen binding proteins indicates that the high-affinity site corresponds to the OSCP subunit of the proton ATP synthase.5. It remains to be determined if P and T also bind to this complex enzyme or if they bind to other subunits of the family of proton ATPases. Overall the data indicate that steroid hormones conjugated to BSA are important tools to study the reality of membrane steroid receptors.