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1.
Infection ; 46(3): 427-430, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29330673

ABSTRACT

A 26-year-old HIV-negative male from Ghana was treated for cervical, intrathoracic and abdominal lymph node tuberculosis (TB) and tuberculous hepatitis. Penetration of the thoracic trachea by a mediastinal lymph node had caused bronchomucosal TB. Sputum culture grew M. africanum, sensitive to all first-line antituberculous drugs. Four weeks after the beginning of directly observed treatment with isoniazid, rifampin, pyrazinamide and ethambutol, the right cervical lymph node increased in size, liquefied and caused a spontaneous fistula. A biopsy of the necrotized lymph node revealed rare acid-fast bacilli with a positive PCR for Mycobacterium tuberculosis complex. After debridement, vacuum-assisted closure therapy was performed for 6 weeks. Five months after the beginning of antituberculous therapy, a second paradoxical reaction occurred, with painful swelling of two contralateral supraclavicular lymph nodes. Extirpation of one node yielded a positive PCR for M. tuberculosis complex; the culture was negative. Antituberculous treatment was continued, and additional treatment with oral prednisolone 20 mg daily for 1 month tapering over 10 weeks was introduced, resulting in a decrease in lymphadenopathy. Antituberculous treatment was continued for a total of 9 months. The outcome was favorable, no further lymphadenopathy occurred over the following 6 months.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Antitubercular Agents/therapeutic use , Lymphadenopathy/drug therapy , Mycobacterium/isolation & purification , Negative-Pressure Wound Therapy/statistics & numerical data , Prednisolone/therapeutic use , Tuberculosis, Lymph Node/drug therapy , Adult , Humans , Lymphadenopathy/diagnosis , Lymphadenopathy/microbiology , Male , Treatment Outcome , Tuberculosis, Lymph Node/diagnosis , Tuberculosis, Lymph Node/microbiology
2.
Nano Lett ; 13(1): 21-5, 2013 Jan 09.
Article in English | MEDLINE | ID: mdl-23214964

ABSTRACT

Controlling the morphology, electronic properties, and growth direction of nanowires (NWs) is an important aspect regarding their integration into devices on technologically relevant scales. Using the vapor-solid-solid (VSS) approach, with Ni as a catalyst and octachlorotrisilane (Si(3)Cl(8), OCTS) as a precursor, we achieved epitaxial growth of rectangular-shaped Si-NWs, which may have important implications for electronic mobility and light scattering in NW devices. The process parameters were adjusted to form cubic α-NiSi(2) particles which further act as the shaping element leading to prismatic Si-NWs. Along with the uncommon shape, also different crystallographic growth directions, namely, [100] and [110], were observed on the very same sample. The growth orientations were determined by analysis of the NWs' azimuths on the Si (111) substrates as well as by detailed transmission electron microscopy (TEM) and selected area electron diffraction (SAED) investigations.

3.
Nano Lett ; 10(10): 3957-61, 2010 Oct 13.
Article in English | MEDLINE | ID: mdl-20843058

ABSTRACT

The applicability of a novel silicon precursor with respect to reasonable nanowire (NW) growth rates, feasibility of epitaxial NW growth and versatility with respect to diverse catalysts was investigated. Epitaxial growth of Si-NWs was achieved using octochlorotrisilane (OCTS) as Si precursor and Au as catalyst. In contrast to the synthesis approach with SiCl(4) as precursor, OCTS provides Si without the addition of H(2). By optimizing the growth conditions, effective NW synthesis is shown for alternative catalysts, in particular, Cu, Ag, Ni, and Pt with the latter two being compatible to complementary metal-oxide-semiconductor technology. As for these catalysts, the growth temperatures are lower than the lowest liquid eutectic; we suggest that the catalyst particle is in the solid state during NW growth and that a solid-phase diffusion process, either in the bulk, on the surface, or both, must be responsible for NW nucleation.

4.
Nanotechnology ; 20(43): 434017, 2009 Oct 28.
Article in English | MEDLINE | ID: mdl-19801756

ABSTRACT

Well-defined monoclinic nanostructures of beta- Ga(2)O(3) were grown in a chemical vapor deposition apparatus using metallic gallium and oxygen as sources. Stable growth conditions were deduced for nanorods, nanoribbons, nanowires and cones. The types of nanostructures are determined by the growth temperature. We suppose that the vapor-solid growth mechanism rules the growth of nanoribbons and rods. For the nanowires we observed catalytic gold droplets atop, characteristic for the VLS growth mechanism with an extremely high growth rate of up to 10 microm min(-1). Nanowires grown on Al(2)O(3) substrates showed an excellent tendency to grow epitaxially, mapping the hexagonal symmetry of Al(2)O(3)(0001).

5.
Nano Lett ; 8(8): 2310-4, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18624392

ABSTRACT

Single crystal silicon nanowires (SiNWs) were synthesized with silane reactant using Au nanocluster-catalyzed one-dimensional growth. We have shown that under our experimental conditions, SiNWs grown epitaxially on Si(111) via the vapor-liquid-solid growth mechanism change their growth direction as a function of the total pressure. Structural characterization of a large number of samples shows that SiNWs synthesized at a total pressure of 3 mbar grow preferentially in the 111 direction, while the one at 15 mbar favors the 112 direction. Specifically by dynamically changing the system pressure during the growth process morphological changes of the NW growth directions along their length have been demonstrated.

7.
Plant Physiol ; 62(5): 687-9, 1978 Nov.
Article in English | MEDLINE | ID: mdl-16660584

ABSTRACT

Chloroplasts isolated from spinach (Spinacia oleracea L., cv. vital(R)) plants grown under controlled light/dark and temperature regimes, contained the phosphorolytic and amylolytic pathways for starch breakdown. The latter consists at least of alpha- and beta-amylase and maltase. Only low amylolytic activity was observed in chloroplasts isolated during the light phase. In chloroplasts prepared during the dark phase, this activity was almost twice as high. These diurnal oscillations of the amylolytic activity were maintained when the plants were kept in prolonged darkness or continuous light. The amylolytic system exhibited a sharp pH optimum between 5.8 and 6.0. Phosphorylase activity, when assayed with saturating concentrations of inorganic phosphate, did not show diurnal fluctuations.

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