A non-growing living biomass of the acidophilic bacterium Thiobacillus ferrooxidans exhibited a high cadmium uptake capacity dependent on pH, on the physiological state and on the nature of the ...biomass. Thus an uptake (0.21 g cadmium g
−1
dry weight) was obtained at pH 1.6 with a non adapted cadmium biomass, harvested in the end of the exponential phase of growth. This uptake was increased up to 0.31 g g
−1
by a biomass tolerant to 0.5 M Cd.
Thiobacillus ferrooxidans tolerates Cr super(3+) up to 75 mM during growth on ferrous sulphate without modification of its bacterial activity (53 mu g protein mM super(-1) Fe super(2+) oxidised). At ...pH 1.4 and in the presence of Cr sub(2)O sub(3), a maximal uptake capacity of 509 mg.g super(-1) dry weight was obtained with biomass harvested in the middle of the exponential growth phase. Cr super(6+) uptake by T. ferrooxidans resulted in the precipitation of a chromium-rich compound on the surface bacterial cells, as observed by transmission electron microscopy.
Septic arthritis caused by Neisseria gonorrhoeae is mono or pauciarticular. They represent a nonrare cause of arthritis in sexually active adults. He is necessary to think of it even in the absence ...of urethritis.
We report the case of gonococcal arthritis without urethritis in a young man associated with positive synovial fluid culture and negative blood cultures.
Prompt recognition and treatment of this disease results in cure without aftereffects. The finding of penicillin-resistant organisms reinforces recent recommendations that advanced-generation cephalosporin must be used as initial therapy.
Renal tubular sodium handling was investigated prospectively in 48 normotensive subjects, 53 untreated hypertensive patients, and 13 patients with white coat hypertension using endogenous trace ...lithium as a marker of proximal sodium reabsorption. A 12-hour daytime ambulatory blood pressure recording was performed in all patients to confirm the diagnosis of hypertension. Patients were included in the white coat hypertension group if their office blood pressure was above 160/90 mm Hg but the mean value of their 12-hour ambulatory recording was lower than 140/90 mm Hg. All participants were studied on their normal diet and ate salt freely. Fractional excretions of sodium (FENa), lithium (FELi), and potassium (FEK) were measured simultaneously before blood pressure recording. FENa was significantly higher in hypertensive patients (0.84 +/- 0.05%, P < .05) than in normotensive control subjects (0.60 +/- 0.06%), and FELi was comparable in the two groups (15.4 +/- 0.65% in hypertensive patients and 17.0 +/- 0.9% in control subjects). However, the relation between FENa and FELi was significantly different in normotensive subjects and hypertensive patients (P < .001), so that for a given increase in FENa a smaller increase in FELi was observed in hypertensive patients. In addition, the ratios of urinary lithium to sodium and urinary potassium to sodium were significantly reduced in hypertensive patients, suggesting an increased proximal reabsorption of sodium. Similar alterations in renal tubular sodium handling were observed in patients with white coat hypertension. These results suggest that an increased sodium reabsorption in the proximal tubule may contribute to the maintenance of hypertension and that white coat hypertension might represent a prehypertensive state.
Using data collected by the high energy photoproduction experiment FOCUS at Fermilab we study the doubly and singly Cabibbo suppressed decays
D
+
and
D
s
+
→
K
+
π
+
π
−
. Our measurements of
Γ
(
D
+
...→
K
+
π
+
π
−
)
/
Γ
(
D
+
→
K
−
π
+
π
+
)
=
0.0065
±
0.0008
±
0.0004
and
Γ
(
D
s
+
→
K
+
π
+
π
−
)
/
Γ
(
D
s
+
→
K
+
K
−
π
+
)
=
0.127
±
0.007
±
0.014
are based on samples of
189
±
24
D
+
and
567
±
31
D
s
+
reconstructed events, respectively. We also present Dalitz plot analyses of the two decay channels; the amplitude analysis of the
D
s
+
→
K
+
π
+
π
−
mode is performed for the first time.
The effect of dissociation of the invading electrolyte on the formation of Liesegang bands is investigated. We find, using organic compounds with known dissociation constants, that the spacing ...coefficient, 1 + p, that characterizes the position of the nth band as x n ∼ (1 + p) n decreases with increasing dissociation constant, K d. Theoretical arguments are developed to explain these experimental findings and to calculate explicitly the K d dependence of 1 + p.
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