Effect of amoxicillin use on oral microbiota in young children

Dental plaque samples from 40 children were screened for the presence of bacteria resistant to amoxicillin. Fifteen children had used amoxicillin and 25 had not used any antibiotic in the 3 months prior to sample collection. All (100%) of the children harbored amoxicillin-resistant oral bacteria. The median percentage of the total cultivable oral microbiota resistant to amoxicillin was 2.4% (range, 0.1 to 14.3%) in children without amoxicillin use and 10.9% (range, 0.8 to 97.3%) in children with amoxicillin use, with the latter value being significantly higher (P < 0.01). A total of 224 amoxicillin-resistant bacteria were isolated and comprised three main genera: Haemophilus spp., Streptococcus spp., and Veillonella spp. The biodiversity of the amoxicillin-resistant microbiota was similar among the isolates from children with and without previous antibiotic use. The amoxicillin MIC at which 90% of the isolates were inhibited for isolates from children who had used amoxicillin in the previous 3 months was higher (64 mg liter(-1)) than that obtained for the isolates from subjects who had not used antibiotics (16 mg liter(-1)). The majority of the amoxicillin-resistant isolates (65%) were also resistant to at least one of the three antibiotics tested (penicillin, erythromycin, and tetracycline), with resistance to penicillin (51% of isolates) being the most frequently encountered. However, significantly more (P < 0.05) of the amoxicillin-resistant isolates from subjects with previous amoxicillin use were also resistant to erythromycin. This study has demonstrated that a diverse collection of amoxicillin-resistant bacteria is present in the oral cavity and that the number, proportions, MICs, and resistance to erythromycin can significantly increase with amoxicillin use.     

Lifestyle determinants of high-density lipoprotein cholesterol: the National Heart, Lung, and Blood Institute Family Heart Study

Background

While genetic factors are major determinants of high-density lipoprotein cholesterol (HDL-C), environmental factors also play a role. The latter include 3 modifiable lifestyle factors: alcohol consumption, physical activity, and smoking.

Methods

We compared the relative effects of alcohol, physical activity, and smoking on HDL-C levels, using data from 2309 subjects (1226 women and 1083 men), aged 25 to 91 years, from randomly selected families participating in the National Heart, Lung, and Blood Institute Family Heart Study.

Results

Alcohol consumption was associated with the largest increment in HDL-C (an increase of 9.0-13.1 mg/dL from nondrinker to highest categories); physical activity with a more modest increment (an increase of 3.0-3.3 mg/dL from lowest to highest categories); and cigarette smoking with a large decrement in women (a decrease of 9.9 mg/dL) and a modest one in men (a decrease of 2.6 mg/dL) between nonsmoker and ≥20 cigarettes per day categories. The 3 lifestyle behaviors plus age, body mass index, education, and current estrogen use explained 22.4% and 18.2% of the total variance of HDL-C for women and men, respectively. Alcohol accounted for 28.6% of this variance among women and 50.1% among men; smoking accounted for 6.7% and 3.3%, respectively, and physical activity for 2.7% and 3.6%, respectively, among women and men. Age, body mass index, education, and current estrogen use explained the remaining 62.0% and 43.0%, respectively, of the variance attributed to environmental factors.

Conclusions

This study suggests that, among lifestyle behaviors, alcohol consumption is the more important correlate of HDL-cholesterol.     

Making psychiatric sense of sand: a case of delusional disorder in Saudi Arabia

Somatic delusional disorder is an uncommon psychiatric disorder that has been typically reported in elderly women. This article reviews the literature and describes a Saudi female patient who presented with novel somatic delusion of turabosis--the conviction that she was continually being covered by sand from sandstorms. Although the systematized delusional convictions remained unshakable, her anxiety and mood symptoms responded to a regimen of tricyclic antidepressants and her delusional beliefs resolved within eight weeks of treatment with risperidone. Sociocultural themes and therapeutic approaches to somatic delusional disorder are discussed.     

Computed tomographic angiography for diagnosis of brain death

The authors report two patients with suspected brain death who required confirmatory tests other than clinical examination because of prolonged barbiturate administration for intracranial hypertension. Absence of intracranial blood flow was documented on CT angiography and confirmed by CT perfusion images. Cerebral angiography confirmed the findings consistent with brain death. CT angiography with CT perfusion may represent a rapid noninvasive method for diagnosis of brain death.     

Coordination of suck-swallow-respiration in infants born to mothers with drug-abuse problems

To delineate quantitatively differences in suck-swallow-respiration coordination during feeding in term infants exposed to drugs in utero, 16 control infants (10 females, six males; mean birthweight 3209g, standard error of the mean [SEM] 103g) and 15 drug-exposed infants (seven females, eight males; seven cocaine, eight opiates; neonatal abstinence [Finnegan] scores less than 10; mean birthweight 3001g, SEM 93g) were studied in the first three days of life and again at one month of age. Coefficients of variation (COVs) of suck-suck, swallow-swallow, and breath-breath intervals were used as measures of stability of individual rhythms. COVs of suck-swallow and swallow-breath intervals were used to determine stability of multiply integrated rhythms. In the first three days of life, a significantly higher percentage of 'apneic swallows' (runs of three or more swallows not associated with breathing movements, divided by total run-swallows) was noted during feeding in the drug-exposed infants (mean 5.3% SEM 1.7%) compared with controls (mean 0.9%, SEM 0.4%;p<0.02), who also had less breath-breath rhythmic stability (higher COV) and shorter swallow-breath intervals. These differences were no longer evident at one month of age. Opiate-exposed infants were generally more affected than the cocaine-exposed infants. Swallowing was less rhythmic in the drug-exposed cohort, especially in opiate-exposed infants, but this difference also disappeared by one month. In the first days of life, drug-exposed infants were less efficient feeders, ingesting less volume per run-swallow than controls (mean 0.31ml, SEM 0.05ml, versus 0.45ml, SEM 0.05ml;p<0.05). The decreased efficiency appeared to be compensated for by a slightly faster swallow rate (mean 53 swallows per minute SEM 2 versus 47 swallows per min, SEM 1, in controls;p<0.005). By one month of age these differences between groups had disappeared as well. Intrauterine drug exposure, even in infants with relatively mild symptoms of withdrawal, may adversely impact development of brainstem respiratory and swallow centers, thus affecting, albeit transiently, the underlying biorhythms of feeding.     

Stenotrophomonas maltophilia contamination of nebulizers used to deliver aerosolized therapy to inpatients with cystic fibrosis

There is circumstantial evidence that nebulizer equipment may be a source of Stenotrophomonas maltophilia for patients with cystic fibrosis. Eighty-nine inpatient nebulizers were examined for evidence of S. maltophilia contamination of which nine (10%) yielded 14 strains of the bacterium. Environmental samples were obtained from 73 different sites on the ward, of which 17 (23%) yielded a further 21 strains. Positive sites included taps, sink drains, and potable water. Genotyping using ERIC-PCR and pulsed-field gel electrophoresis revealed that two pairs of patients' nebulizers were contaminated with closely related strains. None of the S. maltophilia isolates obtained from the ward environment shared genotypes with those obtained from the nebulizers. The frequency of isolation of S. maltophilia from potable water sources on the ward suggests that contamination may result from using it to clean reusable nebulizer equipment, particularly if this is followed by inadequate drying. Although the actual source of S. maltophilia contamination of hospital-use nebulizer equipment in this study remained elusive, these results have important infection control implications.     

Extracellular glutamate and other amino acids in experimental intracerebral hemorrhage: an in vivo microdialysis study

OBJECTIVE: To determine whether extracellular concentrations of glutamate and other amino acids are significantly elevated after intracerebral hemorrhage and, if so, the temporal characteristics of these changes. Although the role of excitotoxic amino acids, particularly that of glutamate, has been described in ischemic stroke and head trauma, no information exists regarding their possible contribution to the pathogenesis of neuronal injury in intracerebral hemorrhage. DESIGN: Prospective, controlled, laboratory trial. SETTINGS: Animal research laboratory. SUBJECTS: Sixteen anesthetized New Zealand rabbits. INTERVENTION: We introduced intracerebral hemorrhage in each of eight anesthetized New Zealand rabbits by injecting 0.4 mL of autologous blood under arterial pressure into the deep gray matter of the cerebrum. MEASUREMENTS AND MAIN RESULTS: Extracellular fluid samples were collected from the perihematoma region and contralateral (right) hemisphere by in vivo microdialysis at 30-min intervals for 6 hrs. Corresponding samples were similarly collected from both hemispheres in each of eight control animals that underwent needle placement without introduction of a hematoma. Concentrations of amino acids (glutamate, aspartate, asparagine, glycine, taurine, and gamma-aminobutyric acid) in the samples were measured by use of high-pressure liquid chromatography with fluorescence detection. Glutamate concentrations (mean +/- sem) were significantly higher in the hemisphere ipsilateral to the hematoma than in the contralateral hemisphere (92 +/- 22 pg/microL vs. 22 +/- 6 pg/microL) at 30 mins after hematoma creation. A significant increase was observed at 30 mins posthematoma creation in the hemisphere ipsilateral to the hematoma compared with the baseline value. A nonsignificant increase in glutamate concentration persisted in the hemisphere ipsilateral to the hematoma, ranging from 134% to 187% of baseline value between 1 and 5 hrs after hematoma creation. In the hemisphere ipsilateral to the hematoma, a three-fold increase in the concentration of glycine was observed at 30 mins after hematoma creation compared with the baseline level (890 +/- 251 pg/microL vs. 291 +/- 73 pg/microL). There was a significant difference between the hemisphere ipsilateral to the hematoma compared with the ipsilateral (corresponding) hemisphere of the control group at 30 mins posthematoma (890 +/- 251 pg/microL vs. 248 +/- 66 pg/microL). A similar transient increase was observed in taurine and asparagine concentrations at 30 mins after hematoma creation, compared with baseline measurements. Taurine concentrations in the hemisphere ipsilateral to the hematoma were significantly higher than the ipsilateral hemisphere of the control group (622 +/- 180 pg/microL vs. 202 +/- 64 pg/microL) at 30 mins after hematoma creation. CONCLUSIONS: The present study suggests that glutamate and other amino acids accumulate transiently in extracellular fluids in the perihematoma region during the early period of intracerebral hemorrhage. The exact role of these amino acids in the pathogenesis of neuronal injury observed in intracerebral hemorrhage needs to be defined.