Synchrotron radiation micro X-ray fluorescence spectroscopy of thin structures in bone samples: comparison of confocal and color X-ray camera setups.

In the quest for finding the ideal synchrotron-radiation-induced imaging method for the investigation of trace element distributions in human bone samples, experiments were performed using both a scanning confocal synchrotron radiation micro X-ray fluorescence (SR-µXRF) (FLUO beamline at ANKA) setup and a full-field color X-ray camera (BAMline at BESSY-II) setup. As zinc is a trace element of special interest in bone, the setups were optimized for its detection. The setups were compared with respect to count rate, required measurement time and spatial resolution. It was demonstrated that the ideal method depends on the element of interest. Although for Ca (a major constituent of the bone with a low energy of 3.69 keV for its Kα XRF line) the color X-ray camera provided a higher resolution in the plane, for Zn (a trace element in bone) only the confocal SR-µXRF setup was able to sufficiently image the distribution.

Compact pnCCD-based X-ray camera with high spatial and energy resolution: a color X-ray camera.

For many applications there is a requirement for nondestructive analytical investigation of the elemental distribution in a sample. With the improvement of X-ray optics and spectroscopic X-ray imagers, full field X-ray fluorescence (FF-XRF) methods are feasible. A new device for high-resolution X-ray imaging, an energy and spatial resolving X-ray camera, is presented. The basic idea behind this so-called "color X-ray camera" (CXC) is to combine an energy dispersive array detector for X-rays, in this case a pnCCD, with polycapillary optics. Imaging is achieved using multiframe recording of the energy and the point of impact of single photons. The camera was tested using a laboratory 30 µm microfocus X-ray tube and synchrotron radiation from BESSY II at the BAMline facility. These experiments demonstrate the suitability of the camera for X-ray fluorescence analytics. The camera simultaneously records 69,696 spectra with an energy resolution of 152 eV for manganese K(α) with a spatial resolution of 50 µm over an imaging area of 12.7 × 12.7 mm(2). It is sensitive to photons in the energy region between 3 and 40 keV, limited by a 50 µm beryllium window, and the sensitive thickness of 450 µm of the chip. Online preview of the sample is possible as the software updates the sums of the counts for certain energy channel ranges during the measurement and displays 2-D false-color maps as well as spectra of selected regions. The complete data cube of 264 × 264 spectra is saved for further qualitative and quantitative processing.

[Therapeutic options for aggressive fibromatosis]. / Therapieoptionen bei der aggressiven fibromatose.

INTRODUCTION: Aggressive fibromatosis, e.g., desmoid tumour, is a rare neoplasm of the connective tissue with local infiltrative growth. Because of the high recurrence rates and destruction of the surrounding tissue, these tumours are classified as semi-malignant. However, desmoid tumors tend not to metastasise. Arising from deep musculoaponeurotic structures, a monoclonal proliferation of fibroblasts occurs. Radical surgical treatment with tumour excision accompanied by radiotherapy is the current standard therapy that can be supplemented by pharmacological treatment in a few cases. PATIENTS AND METHOD: We report on 9 patients (5 males and 4 females) with surgical therapy for aggressive fibromatosis. The neoplasm was located on the extremities in 7 cases (4 x upper extremity, 3 x lower extremity), one tumour was situated in the chin and one in the rectus abdominis muscle. All patients were treated with radical tumour resection. Postoperatively, adjuvant radiotherapy was performed depending on the resection level of each patient. RESULTS: In 6 cases complete tumour resection (R0) was achieved. Following surgery, regular follow-ups with a physical examination and MR images were performed. In 3 cases a total tumour resection was impossible (R1 resection). The aggressive fibromatosis had infiltrated the pelvis in 2 cases implying a hemipelvectomy for R0 resection which was not practicable. Furthermore, diffuse locoregional infiltration of the chin region occurred in one case. In these cases, an adjuvant radiotherapy with 25 x 2 Gy was started postoperatively after the accomplished wound healing. Treatment with chemotherapeutic agents was not necessary. DISCUSSION: Aggressive fibromatosis is a semimalignant neoplasm of the connective tissue with an extremely high recurrence rate. Macroscopically, indistinct solid lesions are found with the destruction of muscles and other surrounding structures. Therapy of choice is the radical surgical resection. Radiotherapy is indicated for patients with non-resectable tumours. Pharmacological treatment should be considered for patients with unsuccessful local therapy.

[Soft-tissue defects on the dorsum of the hand by extravasation of the cytostatic agents: surgical options of treatment]. / Weichteildefekte an der Streckseite der Hand durch Paravasate im Rahmen systemischer Chemotherapien - chirurgische Therapieoptionen.

Systemic treatment with chemotherapeutic agents is often applied by infusions over peripheral vein cannulae located on the hands and lower arms. Dislocation of the cannulae or vein perforation causes an extravasation of the cytostatic agent. This complication occurs in approximately 0.1 - 6 % of intravenous treatments and is rarely noticed before administration of greater volumes. Depending on the tissue toxicity of the administered substances, the extravasation results in tissue damage of different extents. In a few cases, only conservative therapy is required. The majority of patients, however, needs immediate surgical therapy. The reason for this is the severe tissue damage caused by the chemotherapeutic agent that accumulates in the subcutaneous fat where it destroys the connective and fat tissue, nerves, vessels, tendons and muscles, impairing the functionality of the entire hand and arm. In very severe cases, partial or complete amputation of the extremity is the only treatment. The application of antidotes has been discussed controversially and is not a standard procedure. In the past 11 years, 18 patients with extravasations of chemotherapeutics on the dorsum of the hand were admitted to our department. After radical debridement no primary closure of the resulting defect was advisable in the first operation. In all cases we could later perform a stable wound closure. In our opinion, this two-step procedure with primary radical debridement, temporary wound coverage and later wound closure should be performed regularly.

[Secondary nerve reconstruction in the upper extremity in children--results with respect to number of motor units]. / Sekundäre Nervenrekonstruktionen an Extremitäten im Kindesalter--Ergebnisse unter Betrachtung der Anzahl motorischer Einheiten.

After nerve injury, the therapy of choice is primary suture. If this, however, is not possible or inadequate, a secondary reconstruction must be carried out within a suitable period of time. This study shows results after nerve transplantation within a timeframe of six weeks. Seventeen children with peripheral nerve injuries of the upper extremity were treated. Secondary nerve reconstruction was accomplished by sural nerve transplantation. Eight children, aged from 5 to 13 years, were examined. The median nerve was affected in three and the ulnar nerve in five cases. The examination included clinical and electrophysiological assessments. The length of grafts was correlated with the clinical result. Besides the calculation of sensitive and motor nerve conduction velocity the number of motor units from the flexor pollicis brevis muscle or abductor digiti minimi muscle were determined by motor-unit-estimation (MUE) on both sides. The observation time period was on an average 2.9 years. Results were good to excellent. A persisting Hoffmann-Tinel's sign was found only once in median nerve lesion. Loss of sensitivity following harvesting of sural nerve was not noted as a problem by any of these children. Length of grafts did not affect the results. Standard values were reached in every case in the electrophysiological examination. The number of motor units of the abductor pollicis brevis muscle and abductor digiti minimi muscle decreased to approximately 50% compared to the healthy side. Sural nerve grafting resulted in good motor and sensory function. We recommend grafting within six weeks, as Wallerian degeneration is completed and regeneration from the proximal nerve stump is optimal. Although children have a very good regeneration potential, the examined cases did not achieve a complete restoration of all motor units of the muscles.

Ontogeny of Th1 memory responses against a Brucella abortus conjugate.

Protective immune responses to intracellular pathogens such as Brucella abortus are characteristically Th1-like. Recently we demonstrated that heat-killed B. abortus (HKBa), a strong Th1 stimulus, conjugated to ovalbumin (HKBA-OVA), but not B. abortus alone, can alter the antigen-specific cytokine profile from Th2- to Th1-like. In this report we study the ability of a single injection of B. abortus to switch a Th2 to a Th1 response in immature mice. One-day- and 1-week-old mice were given a single injection of B. abortus in the absence or presence of OVA, and at maturity mice were challenged with an allergenic preparation, OVA with alum (OVA-A). B. abortus given without OVA did not diminish the subsequent Th2 response in either age group. In contrast, mice receiving a single injection of B. abortus-OVA at the age of 1 week, but not those injected at the age of 1 day, had reversal of the ratio of OVA-specific Th1 to Th2 cells and decreased immunoglobulin E levels after allergen challenge as adults. Within 6 h both 1-day- and 1-week-old mice expressed interleukin-12 p40 mRNA following either B. abortus or B. abortus-OVA administration. However, only the 1-week-old mice exhibited increased expression of gamma interferon (IFN-gamma) mRNA. The absence of the early IFN-gamma response in 1-day-old mice may explain their inability to generate a Th1 memory response. These results suggest that at early stages of immune development, responses to intracellular bacteria may be Th2- rather than Th1-like. Furthermore, they suggest that the first encounter with antigen evokes either a Th1- or a Th2-like response which becomes imprinted, so that subsequent memory responses conform to the original Th bias. This has implications for protection against infectious agents and development of allergic responses.

Immunoglobulin G3 from polyclonal human immunodeficiency virus (HIV) immune globulin is more potent than other subclasses in neutralizing HIV type 1.

Passive antibody prophylaxis against human immunodeficiency virus type 1 (HIV-1) has been accomplished in primates, suggesting that this strategy may prove useful in humans. While antibody specificity is crucial for neutralization, other antibody characteristics, such as subclass, have not been explored. Our objective was to compare the efficiencies of immunoglobulin G (IgG) subclasses from polyclonal human HIV immune globulin (HIVIG) in the neutralization of HIV-1 strains differing in coreceptor tropism. IgG1, IgG2, and IgG3 were enriched from HIVIG by using protein A-Sepharose. All three subclasses bound major HIV-1 proteins, as shown by Western blot assay and enzyme-linked immunosorbent assay. In HIV-1 fusion assays using X4, R5, or X4R5 envelope-expressing effector cells, IgG3 more efficiently blocked fusion. In neutralization assays with cell-free viruses using X4 (LAI, IIIB), R5 (BaL), and X4R5 (DH123), a similar hierarchy of neutralization was found: IgG3 > IgG1 > IgG2. IgG3 has a longer, more flexible hinge region than the other subclasses. To test whether this is important, IgG1 and IgG3 were digested with pepsin to generate F(ab')(2) fragments or with papain to generate Fab fragments. IgG3 F(ab')(2) fragments were still more efficient in neutralization than F(ab')(2) of IgG1. However, Fab fragments of IgG3 and IgG1 demonstrated equivalent neutralization capacities and the IgG3 advantage was lost. These results suggest that the IgG3 hinge region confers enhanced HIV-neutralizing ability. Enrichment and stabilization of IgG3 may therefore lead to improved HIVIG preparations. The results of this study have implications for the improvement of passive immunization with polyclonal or monoclonal antibodies and suggest that HIV-1 vaccines which induce high-titer IgG3 responses could be advantageous.

Immunity and protection against Brucella abortus.

Brucella abortus is an intracellular pathogen that causes disease in cattle and in humans. The response against B. abortus involves the whole gamut of the immune system, from innate to adaptive immunity resulting from stimulation of antigen-presenting cells, NK cells, CD4(+) and CD8(+) T cells, and B cells.

Ultrasonic monitoring of zeolite synthesis in real time

Variations of the phase and amplitude of a transmitted ultrasonic wave package were monitored in real time during the synthesis of zeolite A and zeolite X. For both materials, characteristic changes of the measured attenuation and the sound velocity of ultrasonic waves traveling in the reaction fluid were observed, correlating with the processes of gel formation and zeolite crystallization, respectively. Aging effects of the reaction fluids are demonstrated. The observation of the onset of the zeolite crystallization was verified with ex-situ X-ray diffraction (XRD) measurements.

Characterization of Na+-linked and Na+-independent Cl-/HCO3- exchange systems in Chinese hamster lung fibroblasts.

The PS120 variant of Chinese hamster lung fibroblasts which lacks Na+/H+ exchange activity was used to investigate bicarbonate transport systems and their role in intracellular pH (pHi) regulation. When pHi was decreased by acid load, bicarbonate caused pHi increase and stimulated 36Cl- efflux from the cells, both in a Na+-dependent manner. These results together with previous findings that bicarbonate stimulates 22Na+ uptake in PS120 cells (L'Allemain, G., Paris, S., and Pouyssegur, J. (1985) J. Biol. Chem. 260, 4877-4883) demonstrate the presence of a Na+-linked Cl-/HCO3- exchange system. In cells with normal initial pHi, bicarbonate caused Na+-independent pHi increase in Cl(-)-free solutions and stimulated Na+-independent 36Cl- efflux, indicating that a Na+-independent Cl-/HCO3- exchanger is also present in the cell. Na+-linked and Na+-independent Cl-/HCO3- exchange is apparently mediated by two distinct systems, since a [(tetrahydrofluorene-7-yl)oxy]acetic acid derivative selectively inhibits the Na+-independent exchanger. An additional distinctive feature is a 10-fold lower affinity for chloride of the Na+-linked exchanger. The Na+-linked and Na+-independent Cl-/HCO3- exchange systems are likely to protect the cell from acid and alkaline load, respectively.

[Heterologous Müllerian adenosarcoma of the uterus--a rare tumor. Light- and electron-microscopic findings, biological behavior (author's transl)]. / Heterologes Müllersches Adenosarkom des Uterus -- ein seltener Tumor. Licht- und elektronenmikroskopische Befunde, klinische Dignität.

A case of heterologous Müllerian adenosarcoma of the uterus is presented with emphasis on morphologic differentiation, clinical course, prognosis, and treatment. This tumor was described first by Clement and Scully in 1974. Since that time 36 cases have been reported in the literature. The neoplasm consists of benign epithelial and malignant mesenchymal elements. The latter are composed of tissue with homologous and heterologous differentiation. Our microscopic and ultrastructural studies suggested that the heterologous elements were rhabdomyoblasts with a variable degree of differentiation. According to the literature the prognosis of Müllerian adenosarcoma is better than that of malignant mixed Müllerian tumor. The location of the tumor - whether intrauterine or extrauterine - seems to be more important as regards prognosis than the differentiation of the sarcomatous elements. The clinical course in our patients was not different from those described in the literature. Surgical removal of the tumor remains the treatment of choice. Some authors report a better survival rate when surgical treatment is followed by radiotherapy. Chemotherapy may be useful in cases of local or distant metastasis, and in cases of incomplete excision of the tumor mass.