Pulmonary angiitis with atypical lymphoreticular infiltrates in Wiskott-Aldrich syndrome: possible relationship of lymphomatoid granulomatosis and EBV infection

We describe a 12-year-old boy with Wiskott-Aldrich syndrome who developed a pulmonary vasculitis associated with lymphoreticular proliferation, consistent with the histological and clinical diagnosis of lymphomatoid granulomatosis. The lesions were responsive to cyclophosphamide and steroids. The patient has had severely depressed immune function and was shown to have abnormal Epstein-Barr virus (EBV)-specific cellular and humoral immune responses. Lymph nodes obtained at autopsy were positive for EBV genome. In this patient, reactivated EBV infection resulting from impaired immune surveillance of the virus may have been responsible for the development of this paraneoplastic disorder.     

Behavioural strategies used by the hookworms Necator americanus and Ancylostoma duodenale to find, recognize and invade the human host

The infective third-stage larvae of the hookworms Necator americanus and Ancylostoma duodenale infect their human hosts by active skin invasion, but A. duodenale is in addition capable of oral infection. The behaviour of the larvae when crawling on surfaces has already been described. Here we analyse in various in vitro systems the other behavioural invasion phases: activation, penetration, and orientation within the host. The larvae normally remained in a motionless, energy-saving, resting posture. An activation to sinusoidal locomotion was stimulated in both species by similar cues such as touch, vibration, water currents, heat, light, and chemicals. Human breath in addition stimulated searching and waving (nictating) behaviour, which facilitates a change-over to the host. Activating cues in air streams were warmth and moisture; CO₂ activated only in combination with warmth and/or moisture. Penetration behaviour in both species was stimulated by warmth and skin extracts. The stimulating components of skin extracts were fatty acids, but their stimulating characteristics differed from those inducing schistosome cercarial skin penetration. After penetration into agar substrates, both species showed thermo-orientation, but only A. duodenale followed gradients of serum. The directing serum cues were not amino acids and glucose (the supposed cues for schistosome blood vessel localization), but Ringers solution attracted the larvae. The host-finding and host-invasion behaviour of both hookworm species is well adapted to the invasion of the human skin, and there seems to be no particular adaptation of A. duodenale behaviour to the oral infection mode. Hookworm host-finding behaviour is not as complex as that of schistosome cercariae but seems well adapted to the ecological conditions in the transmission sites.     

Studies on the distribution of polioviruses in Surinam

Summary A study of the distribution of polioviruses in Surinam was undertaken by a regular virological examination of stool specimens from children of the 1–5 year age group for a period ranging from the beginning of 1964 to the middle of 1969. All three types of poliovirus were found to circulate continuously in the child population. A correlation was found between an increased level of poliovirus circulation and the appearance of clinical poliomyelitis. The application of trivalent oral vaccine at times that a clear increase of the level of poliovirus circulation was observed, had only a partial effect on this level since the acceptance rate for the vaccine was too low.Conducted with the support of the Surinam Government and the Netherlands Foundation for the Advancement of Tropical Research (WOTRO), and with technical assistance of Miss L. Kletter and Mrs. A. Arron.on temporary detachment at the Central Public Health Laboratory, Paramaribo, Surinam.     

Der Einfluss kondensierter Phosphate auf die Eisen-Resorption

Zusammenfassung Es sollte untersucht werden, ob die kondensierten Phosphate Tetranatriumpyrophosphat, Natriumtripolyphosphat, Hexametaphosphat, Kaliummetaphosphat und Plasmal die Eisenresorption beeinträchtigen. Als Maßstab für diesselbe galten die Hämoglobin- und Erythrocytenregeneration und die Gewichtszunahme anämischer Ratten. Die Anämie wurde durch Phenylhydrazinhydrochlorid-Injektionen bzw. eine eisenarme Ernährung (Milchdiät) hervorgerufen. Bei den herrschenden Versuchsbedingungen konnte ein nachteiliger Einfluß der getesteten Substanzen auf die Eisenresorption nicht nachgewiesen werden. Auf Grund dieser Versuche und allgemeiner Überlegungen wurde geschlossen, daß dies überhaupt unter physiologischen Bedingungen unwahrscheinlich ist.     

Public health impact of isoniazid-resistant Mycobacterium tuberculosis strains with a mutation at amino-acid position 315 of katG: a decade of experience in The Netherlands

A previous limited study demonstrated that Mycobacterium tuberculosis isolates with a mutation at amino-acid position 315 of katG (Delta315) exhibited high-level resistance to isoniazid and were more frequently resistant to streptomycin. In the present study, isoniazid-resistant M. tuberculosis isolates from 8,332 patients in The Netherlands (1993-2002) were screened for the Delta315 mutation. Isoniazid resistance was found in 592 (7%) isolates, of which 323 (55%) carried Delta315. IS6110 restriction fragment length polymorphism analysis showed that Delta315 isolates occurred in clusters, suggesting recent transmission, at the same frequency as isoniazid-susceptible isolates. In contrast, other isoniazid-resistant isolates clustered significantly less frequently. Delta315 isolates were high-level isoniazid-resistant, streptomycin-resistant and multidrug-resistant significantly more often, and may have a greater impact on public health, than other isoniazid-resistant isolates.     

Photoelectric recording of mechanical responses of cardiac myocytes

A method to monitor contraction of isolated myocytes by transmicroscopic photometry is illustrated. Two photodiodes are mounted inside an inverse microscope used for visual control of a cell. Illumination of one diode varies in proportion to changes in cell length. The contraction signal is amplified in a comparator circuit. Spatial resolution of the device is in the order of 1 m which corresponds to about 5% of cell shortening in the fully activated state of contraction. The method was tested on isolated myocytes from guinea-pig ventricle. Optical records of contraction in response to action potentials or during voltage clamp compare well with the contractile behaviour of multicellular preparations.     

Histidine-rich protein genes and their transcripts in Plasmodium falciparum and P. lophurae

The presence of histidine-rich protein (HRP) related genes and gene products in Plasmodium falciparum was demonstrated using a synthetic pentahistidine-encoding oligonucleotide and a cloned HRP cDNA probe prepared from the avian parasite P. lophurae. In Northern blotting experiments, two knobby clones of P. falciparum were found to contain a 3500 nucleotide RNA species that hybridized with the oligonucleotide and HRP cDNA probes. As this component had the expected size for an mRNA encoding an 80-90 kDa protein and was absent from two knobless clones of P. falciparum, we concluded that it represented a 'knob protein' mRNA. Using the restriction enzyme EcoRI, three identical cross-hydribizing HRP gene fragments were found in the DNA of both knobby and knobless clones of P. falciparum. These fragments differed in size from those present in P. lophurae. These results suggest that the absence of knob protein mRNA in knobless clones is not due to loss of the corresponding gene(s).     

Extracting information on pneumonia in infants using natural language processing of radiology reports

Natural language processing (NLP) is critical for improvement of the healthcare process because it can encode clinical data in patient documents. Many clinical applications such as decision support require coded data to function appropriately. However, in order to be applicable for healthcare, performance must be adequate. A valuable automated application is the detection of infectious diseases, such as surveillance of pneumonia in newborns (e.g., neonates) because the disease produces significant rates of morbidity and mortality, and manual surveillance is challenging. Studies have demonstrated that automated surveillance using NLP is a useful adjunct to manual surveillance and an effective tool for infection control practitioners. This paper presents a study evaluating the feasibility of an NLP-based monitoring system to screen for healthcare-associated pneumonia in neonates. We estimated sensitivity, specificity, and positive predictive value by comparing results with clinicians' judgments. Sensitivity was 71% and specificity was 99%. Our results demonstrated that the automated method was feasible.     

Automated DNA fingerprinting analysis of Mycobacterium tuberculosis using fluorescent detection of PCR products.

DNA fingerprints of Mycobacterium tuberculosis are produced by restriction fragment length polymorphism analysis of the insertion element IS6110. We modified a PCR-based subtyping method, mixed-linker PCR with fluorescent-labeled IS6110-specific oligonucleotides, to demonstrate rapid, automated, and unattended electrophoretic analysis. Variation in band sizing (normally occurring with fragment mobility), an artifact of lane-to-lane and gel-to-gel differences, was controlled with an internal lane standard, resulting in accurate and precise DNA sizing. By using this method, fingerprint analysis can be performed using actual fragment length rather than estimated position analysis.