Chlorpropamide-induced pure white cell aplasia

We investigated the mechanism for isolated agranulocytosis and marrow pure white cell aplasia in an elderly man receiving 0.5 to 1.0 g per day of chlorpropamide (Chl) without other toxic drug exposure or overt systemic illness. Patient marrow revealed an absence of recognizable granulocytic precursors; megakaryocytes and erythroid precursors were normal. The WBC count was 1800/mm3 on admission with only 2% neutrophils; the absolute neutrophil count first exceeded 500/mm3 on the 17th day following cessation of Chl. A serum Chl level on admission was 100 micrograms/mL (acute phase, AP); no Chl was detected in serum (convalescent phase, CP) assessed on the 22nd hospital day. Antineutrophil antibodies were not detected, and T cell depletion failed to augment patient in vitro granulopoiesis. Patient AP serum produced potent complement-mediated inhibition (87% +/- 7%) of autologous granulocyte progenitors (CFU-GM) with minimal inhibition of erythroid (11% +/- 5%) or multipotent (5% +/- 4%) progenitor cells. Selective inhibition by patient AP serum of CFU-GM (74% +/- 11%) was also seen against two allogeneic marrows. Patient CP serum no longer inhibited (6% +/- 4%) autologous CFU-GM. Addition of Chl (5 to 120 micrograms/mL) to CP serum but not to control serum resulted in potent drug concentration-dependent complement-mediated inhibition of autologous and allogeneic CFU-GM. Inhibition of CFU-GM in the presence of Chl was no longer demonstrable following immunoabsorbent removal of IgG from patient serum. Patient serum in the presence of Chl had limited activity against morphologically recognizable marrow granulocytic precursors in a microimmunofluorescence assay. These results are most consistent with the development of Chl-dependent, selective antibody-mediated immune inhibition of granulopoiesis.     

Light and electron microscopic demonstration of osteocalcin antigenicity in embryonic and adult rat bone

Of the noncollagenous proteins in bone, about 20% consists of osteocalcin. This vitamin K-dependent protein can be found in adult bone, but its presence in embryonic bone could not be demonstrated unequivocally by biochemical methods. Therefore, we used light and electron microscopic immunohistochemical methods to investigate whether osteocalcin antigenicity could be demonstrated in radii of 20-day-old rat embryos. The results show that osteocalcin antigenicity can be demonstrated in the bone matrix of adult bone and in the shaft and endochondral bone matrix of embryonic bone. It could not be demonstrated in calcified cartilage matrix. In bone the antigenicity was observed in the early foci of calcification, i.e., the mineralization nodules.     

Motor unit number estimation using high-density surface electromyography.

OBJECTIVE: To present a motor unit number estimation (MUNE) technique that resolves alternation by means of high-density surface EMG. METHODS: High-density surface EMG, using 120 EMG channels simultaneously, is combined with elements of the increment counting technique (ICT) and the multiple-point stimulation technique. Alternation is a major drawback in the ICT. The spatial and temporal information provided by high-density surface EMG support identification and elimination of the effects of alternation. We determined the MUNE and its reproducibility in 14 healthy subjects, using a grid of 8 x 15 small electrodes on the thenar muscles. RESULTS: Mean MUNE was 271+/-103 (retest: 290+/-109), with a coefficient of variation of 22% and an intra-class correlation of 0.88. On average, 22 motor unit potentials (MUPs) were collected per subject. The representativity of this MUP sample was quantitatively assessed using the spatiotemporal information provided by high-density recordings. CONCLUSIONS: MUNE values are relatively high, because we were able to detect many small MUPs. Reproducibility was similar to that of other MUNE techniques. SIGNIFICANCE: Our technique allows collection of a large MUP sample non-invasively by resolving alternation to a large extent and provides insight into the representativity of this sample. The large sample size is expected to increase MUNE accuracy.     

Lumbar iohexol myelography and diagnostic lumbar puncture. Headache and associated side effects in relation to neurological signs and diagnosis, previous mental symptoms and pain history

Various possible risk factors for postlumbar puncture (and postiohexol-myelographic) headache and associated side effects were analysed. Headache and nausea occurred significantly more often in patients without clinical findings than in those with findings. We found significantly different incidences of severe headache and nausea between diagnostic subgroups after a lumbar puncture. The greatest headache incidence was found in patients without a definite neurological diagnosis, while nausea occurred most frequently in patients with various painful disorders. Following iohexol myelography, nausea occurred most often in patients who had a history of previous mental symptoms and in patients with a history of previous headache disorders. Mental symptoms were more frequently reported in patients who also had experienced mental symptoms previously. The relationship between side effects and negative clinical findings was stronger than the relationship between side effects and previous mental symptoms.     

核、膜蛋白的基因能抑制禽类流感病毒及其重组株的繁殖

对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。     

An optical study of conformation of the aminofluorene-DNA complex

Calf thymus DNA was modified with 2-aminofluorene (AF) to differentextents by treatment with N-hydroxy-2-amino-fluorene. The AF-modifiedDNAs together with free AF, the AF-modified guanine (Gua-C8-AF)and the AF-modified deoxyguanosine (dGuo-C8-AF) were subsequentlystudied by u.v. absorbance, linear dichroism and fluorescencespectroscopy. The emission and absorption properties of doublestrandedDNA-AF and single-stranded DNA-AF closely resemble those ofdGuo-C8-AF. The emission spectra of these three compounds showa broad, red-shifted emission, characteristic for exdplex formation.The linear dichroism and circular dichroism spectra of double-strandedDNA-AF show that the AF moiety forms a well-defined, regularstructure. The dichroic ratio in the 310–340 nm regionis constant, which indicates the presence of only one type ofadduct. The long-wavelength transition moment of this adductmakes an angle of 72–74° with the DNA helix axis.The binding of AF to double-stranded is DNA is accompanied bya destabilization of the DNA helix structure, a strong quenchingof the AF emission quantum yield, intense AF circular dichroismand an apparent immobilization of the dGuo-C8-AF complex. Insingle-stranded DNA-AF, the AF conformation appears more random,although the interactions between AF and the surrounding basespersist. The strong interactions between AF and the surroundingbases which dominate the optical properties of the studied complexes,the significant destabilization of the DNA double helix aftermodification with AF, and the relatively small angle betweenAF and the base planes support a model in which the adduct isinserted into the DNA helix.     

Detrusor properties related to prostatism

Urodynamic testing of 211 patients with prostatism symptoms showed that symptoms were related to detrusor instability, low detrusor strength, or low detrusor speed in the absence of obstruction in 72 patients and in combination with outlet obstruction in 139 patients. Detrusor instability is not related to the degree of outlet obstruction; detrusor strength does not increase with increasing outlet resistance; and detrusor speed is decreased in the obstructed group. BPH, as an obstructive entity, is overdiagnosed.