Prevalence of gram-negative rods in the normal pharyngeal flora

We obtained throat cultures from 100 randomly selected people free from any chronic upper or lower respiratory disease who did not work in a hospital and who had not experienced any acute illness or received any antibacterial therapy in the 4 weeks preceding culture. Eighteen percent harbored either a species of Enterobacteriaceae or Pseudomonas aeruginosa in their pharynx. In all cases, colony counts were low, the majority being detected in broth media selective for Gram-negative rods. There were no clear-cut age or sex distributions of Gram-negative pharyngeal carriage. These data imply that, in at least some cases, isolation of Gram-negative rods from sputum of untreated patients may be a normal finding, and that in some patients with pulmonary infection, the pretreatment, upper respiratory tract flora may serve as the source of subsequent superinfection with Gram-negative rods.     

Occurrence of extended spectrum beta-lactamases (ESBL) and inducible beta-lactamases (IBL) in clinical strains of gram-negative rods

Hairy cell leukemia (HCL) is clinically associated with severe T-cell dysfunction. Several new observations have given more insight into the abnormal T-cell responses seen in this disease. T-lymphocytes in the spleen of patients with HCL seem to be abnormally activated. On the other hand, they are non-responsive, possibly as a result of monocytopenia which may lead to inadequate antigen presentation. This, together with the lack of CD28 on T-cells, may cause T-cell dysfunction. Furthermore, there is a very restricted repertoire of the T-cell receptor-beta family, which may also result in non-responsiveness. Otherwise, T-cell clonal excess may be indicative for activated, possibly autoreactive T-cells.     

Occurrence of gram-negative non-fermenting rods in hemocultures and their sensitivity to antimicrobial agents

In the period from January 1993 to June 1996 were at the Department of Microbiology of the University Hospital in Olomouc 122 strains of Gram-negative nonfermentative rod-shaped bacteria isolated from haemocultures. The majority represented the group of 51 strains of the genus Acinetobacter (41.8%), complex A. calcoaceticus-baumannii (Acb complex). The second largest group were 21 strains (17.2%) of Pseudomonas aeruginosa. These were followed by 17 strains (13.9%) of Stenotrophomonas maltophilia, 8 strains (6.6%) of non-Acb complex acinetobacters, 6 strains (4.9%) of Pseudomonas putida and 5 strains (4.1%) of Alcaligenes xylosoxidans. The remaining species were represented only by 1-2 strains. In three isolations was the identification impossible. The majority of strains (24.6%) were from the Department of Haematology of the University Hospital in Olomouc. The most frequent diagnoses in patients with positive haemocultures were leukemias and lymphomas (24.6%). The most effective tested antimicrobial agents were ceftazidime (93.4% of sensitive strains) and ofloxacin (91.7%). From the total number of 80 strains detected using the equipment BacT/Alert 120, 22 (27.5%) were isolated repeatedly confirming their role in the etiology of bacteriemic or septic episodes. Because only one blood sample was obtained in 34 cases (58.6%) of the remaining 58 only once detected strains, it was impossible to confirm their etiologic role by repeated isolation. (Tab. 6, Ref. 22.)     

Rapid detection of Shiga-like toxin gene in feces with rapid-cycle polymerase chain reaction

A rapid detection for Shiga-like toxin in feces was developed with the nucleic acid extraction method by silicondioxide-guanidine thiothianate and rapid-cycle polymerase chain reaction by RapidCycler (model 1002; Idaho Technology, RC-PCR here after). Twenty-two fecal samples that were collected from patients with diarrhoea caused by E. coli O157:H7 and frozen for 6 months were examined directly by RC-PCR, conventional PCR assay using by ThermalCycler 9600-R (Roche, TC-PCR here after) and by the culture method using tellurite-cefixime sorbitol MacConkey (direct method). These examinations were done also after being injected into TCV-TSB and incutated at 35 degrees C overnight (indirect method). The sensitivity of RC-PCR and TC-PCR using a diluted suspension of broth enriched at 35 degrees C overnight were 4.1 pg and 410 fg, respectively. Positive results in the direct method were obtained in 7 for RC-PCR, 10 for TC-PCR and 5 for culture. Positive results on indirect assay were obtained in 9 for RC-PCR, 9 for TC-PCR and 7 for culture. It was demonstrated that the RC-PCR assay was able to detect Shiga-like toxin gene in feces in less than 90 minutes after being received at the laboratory.     

Functional characteristics of lateral interactions between rods in the retina of the snapping turtle

1. Intracellular recordings were made of the slow hyperpolarizing light responses of single rods in the retina of the snapping turtle. Physiological criteria used to identify rods were verified by intracellular injections of Procion Yellow. 2. The amplitudes of the responses elicited by fixed intensity flashes increased as the stimulus was enlarged to a diameter of 300 mum. Scattered light was found incapable of accounting for this effect, which must result from summative interaction of rods with neighbouring receptors. Effects of summative interaction were observed even at stimulus intensities that produced maximal responses. Enlarging the diameter of the higher intensity stimuli from 100 to 300 mum increased the peak response amplitude by almost 50%; it also produced a distinct initial peak of the response which we term overshoot. The amplitude of this overshoot was graded with stimulus size. 3. Complete intensity-response relationships were determined using stimulus diameters of 100 and 750 mum for each rod. With the smaller stimulus the intensity response range was 4-5 log units, and with the larger stimulus this was increased to 5-0 log units. For intensities below about 60 quanta/mum2 per flash (514 nm) the amplitudes elicited by the large stimulus followed a sigmoid-shaped curve. However, at higher intensities an additional lobe appeared on the intensity-response relationship. The appearance of this lobe correlated with the emergence of the overshoot on the response wave form. 4. Determinations of rod flash sensitivity (mV per quantum per mum2) showed that it increased with stimulus size up to a stimulus diameter of about 300 mum. With diameters between 50 and 150 mum, a linear relationship existed between the flash sensitivity and stimulus area. Absolute quantal sensitivities increased with stimulus area by a factor of 26, from a value of 28 muV per photoisomerization per rod with a stimulus 25 mum in diameter, to 720 muV per photoisomerization per rod with a stimulus 300 mum in diameter. 5. By comparison, red-sensitive cones showed increased sensitivity as a function of stimulus size only up to a stimulus diameter of 120 mum. Their over-all sensitivity was lower than that of rods and proved linear with stimulus diameter rather than with stimulus area. 6. Simultaneous recordings were made from rod-cone pairs to determine whether the overshoot, and hence the lobe on the amplitude-intensity function, could result from a cone input to the rod response. The time course of the cone response proved much too rapid to fit the overshoot of the rod response. 7. The spectral sensitivity of the dark-adapted rod response closely followed the difference spectrum of the rod photopigment for wave-lengths greater than 450 nm. This was true throughout the intensity range of the response, including low intensities where response averaging was necessary. 8. At low response amplitudes (approximately 1 mV), about 70% of the 40 rods tested showed responses to long wave-length stimuli consisting of two components...     

Rapid diagnosis of asymptomatic hereditary haemochromatosis by detection of the Cys282Tyr mutation in the HLA-H gene

Hereditary haemochromatosis is an autosomal recessive disorder characterised by life-long excessive accumulation of iron. A candidate gene for hereditary haemochromatosis has recently been reported (HLA-H) and a specific missense mutation (Cys282Tyr) has been identified in 85% of patients with the disorder. We describe the rapid detection of this mutation using the polymerase chain reaction and restriction endonuclease digestion. The usefulness of this test for early diagnosis of hereditary haemochromatosis in asymptomatic family members is highlighted.     

Rapid detection of K-ras gene mutations in canine lung cancer using single-strand conformational polymorphism analysis

A total of 126 spontaneous lung tumors from pet dogs were examined for K-ras mutations within exon 1 and exon 2 using a non-radioisotope single-strand conformational polymorphism analysis (SSCP) detection method on PCR products. Mutations were confirmed by direct DNA sequencing. Tumors were classified as adenomas (9), bronchioloalveolar carcinomas (59), adenocarcinomas (30), adenosquamous carcinomas (16), squamous cell carcinomas (3) and anaplastic carcinomas (9). Nineteen mutations were detected in the malignant tumors: 18 occurred in exon 1 codon 12 and one in exon 2 codon 61. No mutations were present in the adenomas. The most common mutation was a G-->A transition (11/19) in the second position of codon 12. Based on this study, K-ras mutations occur in canine non-small cell lung carcinomas. The frequency and type of mutation more closely matches tumors from human non-smokers with K-ras mutations than smokers. With the application of screening techniques such as SSCP, large numbers of dog tumors can be examined to provide a large animal model for comparative studies of carcinogenesis.     

Occurrence of homologs of the Escherichia coli lytB gene in gram-negative bacterial species

The Escherichia coli LytB protein regulates the activity of guanosine 3',5'-bispyrophosphate synthetase I (RelA). A Southern blot analysis of chromosomal DNA with the E. coli lytB gene as a probe revealed the presence of lytB homologs in all of the gram-negative bacterial species examined but not in gram-positive species. The lytB homologs from Enterobacter aerogenes and Pseudomonas fluorescens complemented the E. coli lytB44 mutant allele.     

Rapid detection of different RNA respiratory virus species by multiplex RT-PCR: application to clinical specimens

Inconsistent findings from recent mortality studies of workers exposed to magnetic fields have led to calls for more detailed understanding of exposure distributions and metrics in various industries. The authors undertook personal monitoring at an automobile transmission plant to (a) learn if magnetic field exposure differences were present, (b) make assignments for a brain cancer study, and (c) compare two exposure indices. A wide range of average exposures occurred (i.e., 0.016-4.6 microtesla). Within-day variability was also large, and it reached 4 orders of magnitude for some workers. Unexpectedly, demagnetizers were found among the strong sources that contributed to elevated exposures. The authors used conventional summary measures to assign job groups to exposure categories, and they used a new index of exposure irregularity to make alternative assignments. These new assignments appeared to differ from the original ones with respect to work time in each exposure group (i.e., 54% of the work time fell into different exposure categories).     

Controlled clinical evaluation of Isolator and ESP aerobic blood culture systems for detection of bloodstream infections

A controlled clinical evaluation comparing the Isolator system (Wampole Laboratories, Cranbury, N.J.) and the ESP 80A blood culture bottle in the automated ESP system (Difco Laboratories, Detroit, Mich.) was performed with 10,535 blood culture sets from patients with suspected septicemia. Of 1,150 positive cultures, 844 positive cultures from 285 patients with 394 septic episodes fulfilled the study criteria for minimum blood sample requirements in each system and clinical significance of isolates. The Isolator system detected statistically significantly more positive cultures of Staphylococcus aureus (P < 0.001), Enterococcus spp. (P = 0.007), Escherichia coli (P = 0.001), Alcaligenes xylosoxidans (P = 0.02), Xanthomonas maltophilia (P = 0.01), Candida albicans (P < 0.001), and Candida glabrata (P = 0.05). The Isolator system detected significantly more septic episodes due to S. aureus (P < 0.001), X. maltophilia (P = 0.02), and C. albicans (P = 0.004) than did the ESP 80A bottle; however, the two systems did not otherwise significantly differ in their abilities to detect septic episodes due to other organisms.     

Antimicrobial activity of fluoroquinolones and other antibiotics on 1,116 clinical gram-positive and gram-negative isolates

A total of 1,116 clinically isolated strains belonging to Staphylococcus aureus (200), Staphylococcus epidermidis (200), Streptococcus pneumoniae (20), Escherchia coli (200), Klebsiella spp. (177), Serratia marcescens (22), Pseudomonas aeruginosa (224), Haemophilus influenzae (35) and Salmonella (38) from the Department of Infectious Diseases, La Sapienza University in Rome (Italy) were tested against three fluoroquinolones (ofloxacin, ciprofloxacin and levofloxacin) and 10 other antibiotics (augmentin, ampicillin, cefaclor, cefixime, cefotaxime, cotrimoxazole, gentamicin, minocycline, oxacillin and vancomycin). Fluoroquinolones inhibited essentially about 100% of H. influenzae, Salmonella and S. pneumoniae, more than 75% of Staphylococcus including methicillin-resistant strains, and about 90% of Enterobacteriaceae and 50% of P. aeruginosa. Minimal inhibitory concentration values ranged from < 0.015 to > 32 micrograms/ml for Klebsiella, S. aureus and epidermidis, E. coli and P. aeruginosa; from < 0.015 to 2 micrograms/ml for Salmonella; from 0.03 to 16 micrograms/ml for Serratia; from < 0.015 to 1 microgram/ml for Haemophilus; and from 0.5 to 2 micrograms/ml for S. pneumoniae. Levofloxacin and to a lesser extent ofloxacin and ciprofloxacin, generally exhibited a greater activity than the other agents against both Gram-positive and Gram-negative bacteria. Regarding the distribution of resistant strains in Italy, we found a peculiar pattern of resistance as far as E. coli and P. aeruginosa were concerned. Quality control parameters are also summarized. S. epidermidis resulted as a new emergent pathogen especially in immunocompromised patients and its level of sensitivity has been modified over the last few years. In fact, the percentage of resistant strains to antibiotics or the percentage of methicillin-resistant isolates (in our study 35%), has gradually increased. Levofloxacin and ofloxacin showed good activity against staphylococcal strains compared with the majority of other antibiotics. These results suggest that the newer quinolones are promising antimicrobial agents for various infections.     

Rapid detection and typing of herpes simplex virus DNA in clinical specimens by the hybrid capture II signal amplification probe test

A second-generation signal amplification, nucleic acid-based test for the rapid detection and typing of herpes simplex virus (HSV) DNA was developed and evaluated with artificial and clinical specimens. The analytical sensitivity of the Hybrid Capture II (HC II) HSV DNA assay was determined by testing either cloned HSV DNA or total genomic HSV DNA titrations and resulted in detection thresholds of between 5 x 10(3) and 1 x 10(4) copies per assay. Specificity was assessed by testing a panel of bacteria and viruses commonly found in the female genital tract. Sensitivity was assessed by testing 112 ulcerative genital lesions by the HC II assay and comparing the results to those obtained by routine cell culture. Discrepant results were resolved by PCR testing. After resolution of the discrepant results, the sensitivity of the HC II assay compared to the consensus result (the results of two of three tests, the HC II assay, culture, and PCR, were in agreement) was 93.2% (41 of 44 specimens), and the specificity was 100% (60 of 60 specimens). Culture gave a sensitivity of 84.1% (37 of 44 specimens) and a specificity of 100% (60 of 60 specimens) compared to the consensus result. The results of HSV typing by the HC II assay and culture agreed in all cases. The HC II assay is a rapid and accurate assay for detecting and typing HSV types 1 and 2, with a sensitivity comparable to that of culture and greater ease of use than culture.     

Note on clinical judgment and the formal characteristics of clinical tasks.

Analysis of clinical judgment studies by F. J. Todd (1954), K. R. Hammond et al (see record 1965-08022-001), S. Oskamp (see record 1968-02701-001), L. R. Goldberg (see record 1970-12828-001), and R. M. Dawes (see record 1971-25701-001) suggests that the same relation between consistency of inferences and task predictability holds in clinical inferences as in laboratory learning studies. Findings indicate that, to understand the process of clinical inference, it is insufficient to analyze only the clinician; it is also necessary to analyze the clinician/clinical-task system. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parathyroid MEN1 gene mutations in relation to clinical characteristics of nonfamilial primary hyperparathyroidism

Biochemical signs and severity of symptoms of primary hyperparathyroidism (pHPT) differ among patients, and little is known of any coupling of clinical characteristics of nonfamilial pHPT to genetic abnormalities in the parathyroid tumors. Mutations in the recently identified MEN1 gene at chromosome 11q13 have been found in parathyroid tumors of nonfamilial pHPT. Using microsatellite analysis for loss of heterozygosity (LOH) at 11q13 and DNA sequencing of coding exons, the MEN1 gene was studied in 49 parathyroid lesions of patients with divergent symptoms, operative findings, histopathological diagnosis, and biochemical signs of nonfamilial pHPT. Allelic loss at 11q13 was detected in 13 tumors, and 6 of them demonstrated previously unrecognized somatic missense and frameshift deletion mutations of the MEN1 gene. Many of the detected mutations would most likely result in a nonfunctional menin protein, consistent with a tumor suppressor mechanism. Clinical and biochemical characteristics of HPT were apparently unrelated to the presence or absence of LOH and the MEN1 gene mutations. However, the demonstration of LOH at 11q13 and MEN1 gene mutations in small parathyroid adenomas of patients with slight hypercalcemia and normal serum PTH levels suggest that altered MEN1 gene function may also be important for the development of mild sporadic pHPT.     

Rapid detection of species of the opportunistic yeast Trichosporon by PCR

Trichosporon species are opportunistic pathogens, associated with a high mortality rate in immunocompromised patients. Oligonucleotide primers were used to amplify a 170-bp fragment of small-subunit ribosomal DNA of all species in the genus Trichosporon by PCR. The primers amplify DNAs of all species in the genus Trichosporon, including six causative agents of trichosporonosis. DNAs of other medically important yeasts, such as Candida albicans and Cryptococcus neoformans, are not amplified by this detection system.     

Design and evaluation of malolactic enzyme gene targeted primers for rapid identification and detection of Oenococcus oeni in wine

The evaluation of the surgical results in patients operated on for intracranial aneurysms is still controversial, since a satisfactory method able to provide complete informations and ease to use is not still available. The more often used evaluation criteria provide standardized patterns, but the excessive simplifications affect the reliability of the final evaluation. Therefore, I suggest a brand new scale called Clinical Social Emotional Evaluation (CESE), based upon the following domains: neurological evaluation, psychomotor autonomy, return to prior job, behavioural and affective disorders, social reintegration and occurrence of seizures. In order to validate this scale, 190 patients operated on for intracranial aneurysms were assessed. Different scales provided different results. In detail, the number of the "best results" according to CESE was smaller (48%) when compared to the number provided by GOS (80%) and Rankin (62%). Nevertheless, the smaller amount of good results does not imply an overall worsening of the outcome. It is due to the different selection criteria employed by the diverse scales. Indeed, CESE selects groups of patients very homogeneously, whilst other scales include much more heterogeneous subjects. Thus, CESE would prove it-self to be a reliable, accurate and easy to use evaluation scale.     

Rapid detection of aneuploidies by microsatellite and the quantitative fluorescent polymerase chain reaction

Several studies have been performed to assess the diagnostic value of using small tandem repeat (STR) markers and quantitative fluorescent polymerase chain reaction (QF-PCR) assays for the rapid detection of aneuploidies involving chromosomes 21, 18, 13 (Mansfield, 1993; Pertl et al., 1994, 1996; Adinolfi et al., 1995a). The results of these investigations have documented the diagnostic advantages of this approach to perform prenatal tests using amniotic and chorionic samples, or fetal nucleated cells retrieved from peripheral maternal blood or endocervical samples. The use of two or more STR markers for each autosome facilitates the diagnosis of aneuploidies, while avoiding the need to employ internal non-polymorphic markers. Multiplex quantitative fluorescent analyses can be performed in about six hours from the collection of the samples and, although targeted to specific abnormalities, they can exclude the presence of the most frequent chromosomal disorders. QF-PCR can be exploited to analyse DNA present in single or clumps of cells and thus to perform prenatal diagnoses on maternal peripheral blood or transcervical cell samples and on preimplantation embryos.