A clinicopathologic analysis of AIDS-related cryptosporidiosis

OBJECTIVE: To characterize the histology of AIDS-associated cryptosporidiosis and identify features that explain the clinical variability. DESIGN: A retrospective analysis of HIV-positive individuals with cryptosporidiosis who underwent endoscopy at the Johns Hopkins Hospital between 1985 and 1996. METHODS: The histologic features (intensity of Cryptosporidium infection, inflammation, mucosal damage, copathogens) of gastrointestinal biopsies from 37 HIV-positive individuals with cryptosporidiosis were systematically graded. These histologic features were correlated with the severity of the diarrheal illness obtained from a patient chart review. RESULTS: Histologic features associated with Cryptosporidium infection include a neutrophilic infiltrate in the stomach, villus blunting in the duodenum, cryptitis and epithelial apoptosis in the colon, and reactive epithelial changes in the stomach and duodenum. The nature and intensity of the inflammatory response varied widely; however, duodenal biopsies from a subset of patients (37%) revealed marked acute inflammation that was associated with concomitant cytomegalovirus infection. Although duodenal infection was common (93% of individuals), infection of other sites was variable (gastric cryptosporidiosis in 40% and colonic cryptosporidiosis in 74%). Widespread infection of the intestinal tract, which included both the large and small intestine, was associated with the most severe diarrheal illness. CONCLUSIONS: Cryptosporidium infection produces histologic evidence of gastrointestinal mucosal injury. The inflammatory response to the infection is variable, and may be modified by copathogens such as cytomegalovirus. The clinical manifestations are influenced, in part, by the anatomic distribution of the infection, with extensive infections involving both small and large intestines producing the most severe illness.     

Comparison of antinociception induced by supraspinally administered L-arginine and kyotorphin

1. Intracerebroventricular (i.c.v.) or intracisternal (i.cist.) administration of kyotorphin (KTP), an endogenous Met-enkephalin releaser, at 5 micrograms per mouse, and L-arginine (L-Arg), a possible KTP precursor, at 30 micrograms per mouse, elicited antinociception in mice to a similar extent, as assessed by the tail-flick test. 2. Intracisternal preadministration of anti-KTP serum abolished the effect of i.cist. KTP and i.c.v. or i.cist. L-Arg, but not of i.c.v. KTP. 3. The antinociceptive effects of i.cist. KTP and of i.c.v. or i.cist. L-Arg disappeared in reserpinized mice, whereas the effect of i.c.v. KTP was unaffected by treatment of mice with reserpine. 4. Intrathecal (i.t.) phentolamine markedly reduced the antinociception induced by i.cist. KTP and by i.c.v. or i.cist. L-Arg, but not by i.c.v. KTP. 5. Intrathecal methysergide attenuated the antinociceptive effects of i.cist. KTP, but not of i.c.v. KTP and i.c.v. or i.cist. L-Arg. 6. These results suggest that the antinociception produced by i.cist. KTP, but not by i.c.v. KTP, is mediated by the brainstem-spinal noradrenergic and 5-hydroxytryptaminergic systems, and that L-Arg given i.c.v. or i.cist. increases KTP formation in the lower brain, possibly the brainstem, resulting in antinociception mediated by the descending noradrenergic system. Therefore, the regional distribution of KTP receptors and KTP synthetase in the brain does not appear to be common.     

S-100 protein-positive dendritic cells in follicular lesions of the thyroid

To assess recall of childhood socioeconomic position for public health research, the authors conducted a cross-sectional study of 352 adult women twin pairs enrolled in Examination II of the Kaiser Permanente Women Twins Study carried out in 1989-1990 in Oakland, California. Among twin pairs, 91% (95% confidence interval (CI) 89-94%) agreed on their father's educational level and 81% (95% CI 77-85%) on their childhood social class. Recall did not differ by adult socioeconomic position, zygosity, race/ethnicity, or age. Thus, epidemiologic studies can validly use retrospective data on childhood socioeconomic position to study its relation to adult health status.     

A high-sensitivity MOS photo-transistor for area image sensor

A new MOS phototransistor, called a double-gate floating surface phototransistor, has been fabricated and evaluated. In the phototransistor cell, the gate area has been divided into two parts, the accumulation section and the detection section, in order to realize a low input capacitance for a high optical gain. The device achieved a noise equivalent exposure of 2×10^-4 lx at 16-ms integration time and a dynamic range of 75 dB with a new line potential modulation operation     

A monoclonal antibody affects chromophore apoprotein interactions of phytochrome A

A monoclonal antibody designated Mep-1 was raised against phytochrome A from pea (Pisum sativum L.). The binding of this antibody (class IgG1) to partially degraded phytochrome (114 kDa) caused a considerable increase in the far-red peak at the red-light-induced stationary state. The effect reached a plateau value when the antibody and phytochrome were present in approximately equimolar amounts. The dark transformation of the far-red-light-absorbing form to the red-light-absorbing form of the 114 kDa phytochrome was inhibited by the addition of the antibody. However, binding of the antibody to the undegraded 121 kDa phytochrome had no effects on the spectrum of the red-light-induced steady state. The site at which the antibody bound to phytochrome was determined to be between amino acid residues 256 and 383 of pea phytochrome A. This is the first report of a monoclonal antibody that enhances the far-red absorption of phytochrome in the red-light-induced photostationary state.     

Isomers of erythro-5-(1-hydroxy-2-isopropylaminobutyl)-8-hydroxycarbostyril, a new bronchodilator

The isomers of erythro-5-(1-hydroxy-2-isopropylaminobutyl)-8-hydroxycarbostyril (1), a new potent and beta2-selective bronchodilator, were synthesized by optical resolution of compound 1 and inversion of the erythro to the threo isomers. The isomers were tested for activities to inhibit histamine-induced bronchospasm and to increase the heart rate of anesthetized dogs. Racemic and (-)-erythro-1 showed potent and beta2-selective bronchodilater activities. Among the isomers, (-)-erythro-1 showed the highest activities and (+)-erythro-1 showed the lowest.     

Luminescent passive-oxidized silicon quantum dots as biological staining labels and their cytotoxicity effects at high concentration

Semiconductor quantum dots (QDs) hold some advantages over conventional organic fluorescent dyes. Due to these advantages, they are becoming increasingly popular in the field of bioimaging. However, recent work suggests that cadmium based QDs affect cellular activity. As a substitute for cadmium based QDs, we have developed photoluminescent stable silicon quantum dots (Si-QDs) with a passive-oxidation technique. Si-QDs (size: 6.5 ± 1.5?nm) emit green light, and they have been used as biological labels for living cell imaging. In order to determine the minimum concentration for cytotoxicity, we investigated the response of HeLa cells. We have shown that the toxicity of Si-QDs was not observed at 112?μg?ml(-1) and that Si-QDs were less toxic than CdSe-QDs at high concentration in mitochondrial assays and with lactate dehydrogenase (LDH) assays. Especially under UV exposure, Si-QDs were more than ten times safer than CdSe-QDs. We suggest that one mechanism for the cytotoxicity is that Si-QDs can generate oxygen radicals and these radicals are associated with membrane damages. This work has demonstrated the suitability of Si-QDs for bioimaging in lower concentration, and their cytotoxicity and one toxicity mechanism at high concentration.     

Ratio of aerosol and gases of radioactive chlorine and particle size distribution of aerosol formed by high-energy proton irradiation

To estimate internal doses due to the inhalation of radionuclides produced by the nuclear spallation of the air nuclei in high-energy proton accelerator facilities, the physicochemical properties of radionuclides are very important. Thus, the ratio of aerosol and gases of 38Cl and 39Cl formed by irradiating argon gas-added air with a 48 MeV proton beam has been measured. Radionuclides of 38Cl and 39Cl exist as aerosol, acid gas and non-acid gas. The percentages of activity of 38Cl and 39Cl aerosols are about 80%. The number size distributions of non-radioactive aerosol were characterised by two peaks with diameters of 10-20 nm and larger than 20 nm. As a result predicted by a simple surface model, it was found that the activity size distribution of 38Cl aerosols can be regarded as that having a single peak at 120 nm.     

Development of real-time process control system for precision and flexible V-bending with an on-line database

An advanced process control system based on expertise is developed for the V-bending process. An experimental database and a fuzzy inference model are employed as the expertise for real-time process control. The punch force-stroke curves and other process parameters stored in the database are retrieved in-process and evaluated by the fuzzy model for precise prediction control. Also, a learning process, which is similar to the way craftsmen acquire knowledge, is applied for database and fuzzy model improvements in order to cope with new materials. Several experiments were carried out to confirm the validity of the developed control system. The results show that the process control is capable of coping with differences in the material properties and other forming parameters automatically even if the operator has no information on the material properties and the process.