Melanotic neuroectodermal tumor of infancy: report of two cases

Melanotic neuroectodermal tumor of childhood is a rare lesion, but its presentation appears to be quite characteristic and a clinical diagnosis may be made with some confidence. Although this is an extremely rapidly growing, aggressive tumor, local excision appears to be adequate for cure.

Regional identity is established before gastrulation in the Xenopus embryo

Regional differences in cell recognition properties along the animal-vegetal axis of Xenopus laevis embryos were investigated by using an in vitro cell sorting assay. Dissociated cells were obtained from defined regions of blastula- and early gastrula-stage embryos. Binary combinations of cells from different regions, or from the same region at different ages, were aggregated in stationary culture. Labelling of one population in each pair with a cell-autonomous dye allowed the degree of sorting out in the resulting aggregates to be scored. In combinations of cells from animal caps (prospective ectoderm) and vegetal masses (prospective endoderm), sorting was detectable at the equivalent of late blastula stage and increased with developmental age to the gastrula stage. In addition, cells from the same region but different stages sorted from each other, indicating temporal changes in regional identity. Marginal cells (prospective mesoderm) sorted strongly from vegetal cells but only weakly from animal cells. These results indicate the presence of regional identity in the form of specific recognition properties in cells of the Xenopus blastula. We suggest that these properties act to establish and maintain coherent cell populations, corresponding to the primary germ layers, prior to gastrulation. These results account for the gradual restriction in developmental capacity of blastomeres seen previously in single-cell transplantation experiments from this laboratory.

Objective tinnitus associated with abnormal mastoid emissary vein

Tinnitus may be defined as the perception of sound in the absence of environmental input. It can be subjective. Objective tinnitus may be caused by clearly definable mechanical or vascular abnormalities, and as such may be amenable to specific management. We report a case of objective tinnitus associated with an abnormal mastoid emissary vein. A review of the literature identified only one other report of objective tinnitus associated with an emissary vein. That report involved a posterior condylar emissary vein. The venous drainage of the sigmoid sinus was studied on 50 human skulls demonstrating three possible emissary veins of each sigmoid sinus. The postauricular region was dopplered on 30 asymptomatic human subjects. None was found to have dopplered emissary vein flow.

The production of Clostridium botulinum toxin in mammalian, avian and piscine carrion

Mice, birds (chicks, quail) and fish (rudd, goldfish) killed shortly after receiving 1300-2000 spores of Clostridium botulinum per os were incubated, usually at 23 degrees C for 7 days. A 10% (w/v) homogenate of each rotting carcass was then prepared, sterilized by membrane filtration, and assayed for toxin. In mouse carcasses a type C strain of C. botulinum usually produced greater than 2 X 10(5) mouse intraperitoneal LD/g; in fish carcasses it usually produced less--often much less--than 2 X 10(4) LD/g. Avian carcasses appeared to be intermediate between those of mice and fish in their ability to support toxigenesis. A type E strain of C. botulinum, unlike type C, produced toxin equally well in fish and mouse carrion, usually at a concentration of between 2 X 10(4) and 2 X 10(5) LD/g.

Job satisfaction and attitudes of nursing staff on a unit for the elderly severely mentally infirm, with change of location

Relocation of the elderly has stimulated research into its effect on this vulnerable group. This study, by contrast, focuses attention on the staff response to relocation. Nursing staff on an Elderly and Severely Mentally Infirm Unit (ESMI) who were caring for the 50-60 inpatients completed a questionnaire, measuring job satisfaction and work-related attitudes, immediately and after the relocation to a newly refurbished unit. A follow-up was conducted 8 months after the change of environment. Only after the 8-month follow-up had overall levels of job satisfaction improved significantly. No changes over time were found in attitude to caring for ESMI patients or views about providing more facilitative activities as opposed to traditional nursing care. On all occasions there was a great sense of co-operation amongst staff, but they were unsatisfied with the pressure of work. Morale and feeling part of a team effort dropped after relocation but regained original levels on follow-up. Staff turnover was high for the duration of the study. Opinions concerning work were not associated with staff leaving immediately on relocation but low satisfaction levels did predict a future exodus of staff from the unit after the relocation.

Methicillin-resistant Staphylococcus aureus: associated morbidity and effectiveness of control measures

The strain of methicillin-resistant Staphylococcus aureus (MRSA) prevalent in south-east England produced in one acute hospital in a year 40 infections (bacteraemia, pneumonia and surgical wound, skin and urinary tract infections) with three attributable deaths. Rigorous measures succeeded in controlling the outbreak despite its extent, but our results suggest that less stringent measures could fail to control outbreaks of this scale. Several subsequent localized outbreaks within the hospital, probably caused by separate re-introductions of MRSA from other hospitals, were controlled by re-instigation of control measures on individual wards. The overall success of the intervention was shown by the decline in the incidence of MRSA infections from 27 in the 6 months beforehand to 2 in the most recent 6 months, and by the decline in the prevalence of colonization among patients 10 or more days in hospital from 52% immediately before the intervention to 3% 7 months after it. The incidence of attributable morbidity and death without control measures warrants a concerted effort to tackle the epidemic in all affected hospitals in Britain.

The penetration of ofloxacin into bronchial secretions

Penetration of ofloxacin into bronchial secretions following a single 400 mg oral dose was studied in 52 patients. Bronchial secretions were aspirated at bronchoscopy between one and 24 h after dosing and blood was collected at the same time. Mean bronchial secretion concentrations between 2 and 2.6 mg/l were measured in 36 patients between 1 and 6 h but there was considerable individual variation in both serum and bronchial aspirate concentrations. Concentrations declined slowly between 9 and 24 h to a mean value of 0.4 mg/l at 24 h. Correlation between serum and sputum concentrations of ofloxacin was fairly good despite marked deviation in some individuals. The ratios of the concentration in bronchial secretion to serum were remarkably constant at 1 to 6 h, varying between 0.96 during the third and fourth hours and 0.81 in the sixth hour. The results suggest that ofloxacin in a 400 mg oral dose is likely to achieve therapeutic activity against respiratory pathogens including Streptococcus pneumoniae, with sustained activity against more sensitive organisms for up to 24 h.

Haemolytic effect of Pasteurella haemolytica on blood from young mammals

On agar plates containing young lamb blood, Pasteurella haemolytica produces a wide outer zone of partial haemolysis in addition to the narrow zone of complete clearing seen on adult sheep blood agar. To determine whether this phenomenon was limited to lamb blood, samples from young animals of 20 mammalian species were examined. Two species--the barbary sheep (Ammotragus lervia) and scimitar horned oryx (Oryx tao)--possessed blood that gave this effect provided that the samples were taken from young animals. The 18 species that gave negative results included an ovine species, the bighorn sheep (Ovis canadensis).

Factors affecting the toxicity of rotting carcasses containing Clostridium botulinum type E

Mice killed shortly after receiving c. 2000 spores of a type E strain of Clostridium botulinum per os were incubated at one of five chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10%, w/v) and pure cultures were then titrated for toxicity. Some of the main findings were confirmed with two further type E strains. Toxicity produced at 37 degrees C was poor in both carcasses and cultures (200-20,000 mouse intraperitoneal LD/g or ml). It was good in both systems at 30 and 23 degrees C, usually reaching 20,000-200,000 LD/g or ml, and in carcasses occasionally more; at 30 degrees C maximal toxicity was reached more quickly in carcasses than in cultures. Prolonged incubation (36-118 days) at 30 or 23 degrees C resulted in complete loss of toxicity in virtually all carcasses but not in cultures. At 16 degrees C the development of toxicity in carcasses was strikingly greater than in cultures. At 9 degrees C neither system produced more than slight toxicity after prolonged incubation. Trypsinization increased the toxicity of cultures but not usually of carcasses. Unfiltered carcass homogenate (10%, w/v) with maximal intraperitoneal toxicity was harmless for mice by mouth in doses of 0.25 ml. These findings differed in important respects from those made earlier with a type C strain.

Reduplicative paramnesia: possible anatomical and neuropsychological mechanisms

A patient is reported who presented with reduplicative paramnesia following a vascular lesion in the right frontal region. Neuropsychological examination revealed significant memory impairment, perservation on a problem solving task and marked left-sided inattention. Recovery from the paramnesic episode was accompanied by selective resolution of the original cognitive deficits. It is suggested that focal right frontal pathology may represent a sufficient condition for the occurrence of reduplicative paramnesia, and that the underlying mechanisms may be dependent on a particular combination and severity of memory, visuospatial and conceptual deficits.

The shelf operation in the management of late presentation of congenital hip dysplasia

Shelf operations performed on 24 patients (27 hips) for late presentation of congenital hip dysplasia were evaluated. The mean age at operation was 14 years 9 months and the mean follow-up 16 years 8 months. Two-thirds of the hips had good clinical results at follow-up. Patients operated on under the age of 20 years and with little or no radiological evidence of degenerative joint changes had the highest likelihood of success. The shelf operation was found to provide good cover of the femoral head and, should failure occur, also provides adequate superior support for the seating of an acetabular prosthesis.

Comparison of high performance liquid chromatographic and microbiological methods for determination of itraconazole

A reversed-phase high-performance liquid chromatographic (HPLC) method, with internal standard quantification, is described for the analysis of itraconazole in human serum. No interference was encountered from over 60 drugs tested. The standard curve was linear from 10 to 10,000 micrograms/l. The detection limit of the method was 10 micrograms/l, with coefficients of variation from 2.2 to 7.8% over a range of itraconazole concentrations from 20 to 1600 micrograms/l. An agar diffusion method is also described with a lowest reproducible limit of 100 micrograms/l. This method had coefficients of variation from 11.0 to 17.1% over a range of itraconazole concentrations from 100 to 1600 micrograms/l. Comparison of the methods showed that HPLC gave much lower values of itraconazole concentrations in patient serum samples than did the microbiological method.

Detection of antibodies in human sera to the repeating epitope of the circumsporozoite protein of Plasmodium falciparum using the synthetic peptide (NANP)3 in an enzyme-linked immunosorbent assay (ELISA)

An enzyme-linked immunosorbent assay (ELISA) was developed to detect antibody in human sera to a synthetic peptide, Asn-Ala-Asn-Pro (NANP)3, derived from the repeating amino acid sequence found in the surface circumsporozoite protein of Plasmodium falciparum sporozoites. One hundred four sera from U.S. residents were used to determine a cut-off value for reactivity. Test sera were considered reactive when the absorbance was greater than that at the 95th percentile of the control sera. Sera from 112 Kenyans living in an area of holoendemic malaria transmission were tested. Of the total number of sera, 65% had detectable antibody to (NANP)3. The percentage of reactive sera increased from 41% in sera from children under 4 years of age to 85% in sera from adults 20 to 39 years of age. The high exposure to malaria parasites of the Kenyans was reflected in indirect fluorescent antibody assay titers to blood stage P. falciparum parasites. All of the Kenyan sera had antibody present at titers greater than 1:256.

Oral dosing of mice with Clostridium botulinum type C cultures and culture filtrates

In two of 14 tests in which adult mice were dosed per os, whole broth culture of Clostridium botulinum type C was more lethal than culture sterilised by membrane filtration. The results indicated that occasionally--though not usually--significant bacterial multiplication and toxigenesis occurred in the gut.

Factors affecting the toxicity of rotting carcasses containing Clostridium botulinum type C

Mice killed shortly after receiving 1300-3000 spores of Clostridium botulinum type C per os were incubated at one of four chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10-20.8%, w/v) and pure cultures were then titrated for toxicity. A temperature of 37 degrees C produced less toxicity in most carcasses than in cultures. At 30 degrees C, however, toxicity (often 2 X 10(5) to 2 X 10(6) mouse intraperitoneal LD/g or ml) was roughly similar in both systems, and some carcasses and cultures were still toxic (2 X 10(4) to 2 X 10(5) LD/g or ml) after 349 days. Surprisingly, at 23 degrees C, through greatly reduced in the cultures, toxicity was high in many carcasses for at least 28 days. Little or no toxin was produced in either system at 16 degrees C. Unfiltered homogenates (17.8-22.5%, w/v; dose 0.25 ml per os) of toxic carcasses incubated at 30 degrees C for 7 days invariably produced death from botulism, often within as little as 4 h, but a 1 in 10 dilution produced less than 100% mortality.