Magnetic field tomography of coherent thalamocortical 40-Hz oscillations in humans.

This paper introduces the use of magnetic field tomography (MFT), a noninvasive technique based on distributed source analysis of magnetoencephalography data, which makes possible the three-dimensional reconstruction of dynamic brain activity in humans. MFT has a temporal resolution better than 1 msec and a spatial accuracy of 2-5 mm at the cortical level, which deteriorates to 1-3 cm at depths of 6 cm or more. MFT is used here to visualize the origin of a spatiotemporally organized pattern of coherent 40-Hz electrical activity. This coherence, initially observed during auditory input, was proposed to be generated by recurrent corticothalamic oscillation. In support of this hypothesis, we illustrate well-defined 40-Hz coherence between cortical-subcortical sites with a time shift that is consistent with thalamocortical conduction times. Studies on Alzheimer patients indicate that, while a similar activity pattern is present, the cortical component is reduced in these subjects.     

Primary health care computing analysis of Swedish maternal health records

In our attempt to develop an “Essential Data Set” for a computer based information system to support Maternal & Child Health Care services an analysis of Swedish maternal care services was undertaken. The present study analyses the information system in the domain of maternal and child health care at the primary health center level with a view to identify areas where a computer-based medical record could effect improvements. The study showed that even in a well organized maternal care service as in Sweden lacunae exist in the information system. The paper forms, called MHV1, MHV2, MHV3 and FV1, though well designed, were incomplete in a large number of the cases. The MHV1 forms were completed in less than 45%, the MHV 2 form in 87.5% and the FV1 form in 70% of the cases. Certain elements of the data set were less likely to be completed than others. Another weak spot was the inaccessibility of the paper records during off-hours. These deficiencies could be eliminated by the use of a computerized medical record based on an essential data set.     

A newly designed attachment device of multipurpose frame for neuronavigator

Summary A newly designed attachment device of the multipurpose head frame (Sugita) for Neuronavigator (Watanabe) is presented with an illustrative case of glioblastoma in an eloquent area. This has extended the usefulness of the neuronavigator for those who prefer and use the multipurpose head frame, while the requirements for keeping a stereotactic combination and the original concept of the multipurpose head frame, as well as that of the neuronavigator have been kept undisturbed.     

Bacteriophage typing in Salmonella bareilly.

A total of 675 strains of Salmonella bareilly received from different parts of India and France during 1959-92 were phage typed using six bacteriophages. Overall typability achieved was 90.8% with 23 distinct phage types excluding a group of untypable strains. Phage types have been defined in octal code. Simpson''s coefficient was applied for diversity index having a value of 0.839. This system was found to be reproducible, stable and epidemiologically useful.     

Clinico-microbiological study of dermatophytoses.

In the present series, 80 cases of dermatophytoses were subjected to mycological examination including microscopy and culture the mycological findings were correlated with clinical presentation of the patients. The isolation rate was 62.5 percent. Fungal culture was successful in 36.25 percent of cases, Trichophyton rubrum being the commonest etiological agent accounting for 55.18 percent of cases.     

Aplasia of submandibular salivary glands associated with ectodermal dysplasia.

We describe a 28-year-old white Caucasian man displaying many of the physical signs of ectodermal dysplasia (ED). An unusual finding was his presentation with xerostomia. Salivary gland imaging techniques revealed aplasia of both submandibular salivary glands and relatively small parotids. The case highlights that hypoplasia and aplasia of exocrine glands could be rare features of ED. In the management of ED, early detection of xerostomia is important to limit any potential damage to the already hypodontic dentition.     

Botulinum versus tetanus neurotoxins: Why is botulinum neurotoxin but not tetanus neurotoxin a food poison?

Botulinum and tetanus neurotoxins, produced by Clostridium botulinum and Clostridium tetani, respectively, are the most poisonous poisons known to mankind. Although botulinum and tetanus neurotoxins share several characteristics, such as similar mol. wts, similar macrostructure, virtually identical mode of action, and a strong amino acid sequence homology, the two neurotoxins differ in one very significant way; only botulinum neurotoxin is a food poison. Factors responsible for the food poisoning potential of botulinum neurotoxins seem to be a group of complexing proteins that are also produced by C. botulinum, and are known to associate with the neurotoxin. Translation products of nucleotide sequences upstream to the neurotoxin genes of serotypes A, B, C, D, E and F botulinum neurotoxin reveal the location of genes for one of the complexing proteins that could be transcribed as polycistronic mRNA to include neurotoxin sequences. No such protein seems to be present in C. tetani, suggesting that the lack of complexing proteins might be responsible for tetanus not being a food poison.     

Screening term LGA neonates for hypoglycemia: the Colorado vs. the Portland Intrauterine Growth Chart

It was postulated that identification of term (LGA) large for gestational age newborns by the Portland Intrauterine Growth Curve rather than the Colorado Curve would classify a lesser number of neonates as LGA, but would identify the LGA neonates at risk for hypoglycemia. One hundred inborn neonates who plotted LGA on the Colorado Chart were reviewed. Sixty-one infants were LGA on the Portland Chart. Of the 100 infants, 17 were found to have dextrostix less than 45 mg% in the first two hours of life, 15 of these had quantitative blood glucose (BG) test performed. Eleven of the 15 neonates had a BG less than 40 mg%; all 11 hypoglycemic neonates were identified LGA on the Colorado Graph whereas only seven were identified LGA by the Portland Graph. The authors conclude that the Colorado Graph is a better tool in their population than the Portland in identifying term LGA neonates at risk for hypoglycemia.