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A morphologic classification and incidence of alveolar-bronchiolar neoplasms in BALB/c female mice.

Lungs from 505 (21.1%) of 2,397 untreated control female BALB/c mice examined at various age intervals up to 1,001 days contained alveolar-bronchiolar neoplasms. Tumors were evaluated for histomorphological type, degree of differentiation, and size. Most of the tumors (286 of 505 or 56% of those examined) were of the papillary type and 450 of 505 (89.1%) were well differentiated. The incidence of the solid type and the well differentiated tumors was highest in the smallest size group (less than 0.5 mm) while that of the papillary and mixed types and the moderately and poorly differentiated tumors was highest in the larger size groupings. One hundred twenty-seven of 131 (97%) of all solid tumors were well differentiated while a lower percentage of papillary and mixed types (86.7% and 85.2%, respectively) were well differentiated. The mean age of mice with tumors from each histomorphological type, degree of differentiation, and size grouping also was determined.

Age Factors↗

The cost of antibiotics in treating upper respiratory tract infections in a medicaid population.

OBJECTIVE: To examine the use and cost of the nonindicated treatment regimens of antibiotics for nonspecific upper respiratory tract infections (URIs) in a Medicaid population. DESIGN: A cross-sectional sample of Kentucky Medicaid claims for 50000 people (July 1, 1993-June 30, 1994). SETTING: Episodes of care were created linking outpatient and emergency department visits for URIs to medications filled within a 5-day period. PARTICIPANTS: Individuals who were seen in ambulatory care for a URI as defined by the International Classification of Diseases, Ninth Revision, Clinical Modification codes 460 and 465. Of the 15706 episodes, 95% were outpatient office episodes. The outpatient episodes were accounted for by 8784 patients and 946 physicians. MAIN OUTCOME MEASURES: Use of antibiotics in URI episodes. Proportionate costs and costs per episode were computed based on claims paid by Medicaid. RESULTS: Sixty percent of outpatient episodes and 48% of emergency department episodes resulted in an antibiotic prescription being filled. In outpatient settings, episodes in which secondary diagnoses of either otitis media or acute sinusitis were found accounted for less than 6% of the episodes that resulted in an antibiotic prescription being filled. The most frequently filled antibiotic was amoxicillin, although second- and third-generation cephalosporins were the second most frequently occurring antibiotic class. Twenty-three percent and 9% of outpatient and emergency department episodes, respectively, resulted in a prescription filled for antihistamines. In outpatient episodes, antibiotics account for 23% of the total cost of care. In emergency department visits, antibiotics account for 8% of the cost of URIs. Antibiotics cost, on average, $9.91 for each episode of care in outpatient office visits. An estimate of the cost of antibiotics for URIs in a year for the Kentucky Medicaid program is $1.62 million. CONCLUSIONS: The results indicate that a substantial proportion of resources in Medicaid are being used for nonindicated and ineffective treatments for URIs. With the increase in antibiotic-resistant pathogens and shrinking public health care funding, the current treatment for URIs should be reexamined.

Aged↗

Serum levels of seven cytokines in premature ventilated newborns: correlations with old and new forms of bronchopulmonary dysplasia.

OBJECTIVE: In addition to the previous classification of chronic lung disease (CLD) O2 dependency at 36 weeks of postmenstrual age, a new definition of CLD has recently been proposed: new bronchopulmonary-dysplasia (BPD). This uses total duration of O2 supplementation and positive pressure requirements to delineate three degrees of severity (mild, moderate, and severe) according to the respiratory status at 36 weeks postmenstrual age. We analyzed the balance of serum proinflammatory and profibrotic/angiogenic cytokine concentrations in relation to CLD and the new BPD definition. DESIGN AND SETTING: Descriptive study in a third-level neonatal ICU. PATIENTS: Thirty-one preterm neonates with a gestational age of 24-29 weeks were studied to evaluate their serum cytokine concentration; they were previously enrolled in a randomized clinical trial to compare the effects of high-frequency oscillatory ventilation vs. intermittent mandatory ventilation in terms of pulmonary mechanics and lung cytokines. Serum samples were collected on days 1, 3, and 5 after birth until extubation to detect the levels of three proinflammatory cytokines plus four profibrotic/angiogenic cytokines, and correlations were examined to old CLD and new BPD. Ventilation treatments were distributed homogeneously between the groups and did not interfere with the results presented here. RESULTS AND CONCLUSIONS: Old CLD development, mainly corresponding to the moderate/severe forms of new BPD, was associated with increased proinflammatory and profibrotic/angiogenic cytokines, while mild forms of new BPD were characterized only by increases in profibrotic/angiogenic cytokines, suggesting a different balance of two pathogenic mechanisms in different phases of the disease.

Bronchopulmonary Dysplasia↗

Nonencapsulated Neisseria meningitidis strain produces amylopectin from sucrose: altering the concept for differentiation between N. meningitidis and N. polysaccharea.

Neisseria meningitidis is the causative agent of meningococcal sepsis and meningitis. Neisseria polysaccharea is a nonpathogenic species. N. polysaccharea is able to use sucrose to produce amylopectin, a starch-like polysaccharide, which distinguishes it biochemically from the pathogenic species N. meningitidis. The data presented here indicate that this may be an insufficient criterion to distinguish between these two species. The nonencapsulated Neisseria strain 93246 expressed a phenotype of amylopectin production similar to that of N. polysaccharea. However, strain 93246 reacted with N. meningitidis serotype 4 and serosubtype P1.14 monoclonal antibodies and showed the N. meningitidis L1(8) lipo-oligosaccharide immunotype. Further analyses were performed on four genetic loci in strain 93246, and the results were compared with 7 N. meningitidis strains, 13 N. polysaccharea strains, and 2 N. gonorrhoeae strains. Three genetic loci, opcA, siaD, and lgt-1 in strain 93246, were the same as in N. meningitidis. Particularly, the siaD gene encoding polysialyltransferase responsible for biosynthesis of N. meningitidis group B capsule was detected in strain 93246. This siaD gene was inactivated by a frameshift mutation at the poly(C) tract, which makes strain 93246 identical to other nonencapsulated N. meningitidis strains. As expected, the ams gene encoding amylosucrase, responsible for production of amylopectin from sucrose, was detected in strain 93246 and all 13 N. polysaccharea strains but not in N. meningitidis and N. gonorrhoeae strains. These data suggest that strain 93246 is nonencapsulated N. meningitidis but has the ability to produce extracellular amylopectin from sucrose. The gene for amylopectin production in strain 93246 was likely imported from N. polysaccharea by horizontal genetic exchange. Therefore, we conclude that genetic analysis is required to complement the traditional phenotypic classification for the nonencapsulated Neisseria strains.

Amylopectin↗

Multi-omics-based study on the biological characteristics of kidney renal deficiency and blood stasis in ankylosing spondylitis.

OBJECIVE: To explore the objective biological evidence for the classification and diagnosis of Traditional Chinese Medicine (TCM) syndromes in ankylosing spondylitis (AS) using multiomics analysis. METHODS: Patients with AS were categorized into kidney deficiency and blood stasis syndrome (SX group) and damp-heat stasis syndrome (SR group). Transcriptomic sequencing and quantitative plasma proteomics were performed on patients with AS and healthy volunteers. Multiomics integration was used to characterize the biological basis of AS with renal deficiency and blood stasis syndrome. Specific proteins were validated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). RESULTS: Transcriptomic sequencing identified 31 significantly upregulated genes in patients with AS compared to healthy controls. These genes were primarily involved in tumor necrosis factor, interleukin-17, and nuclear factor kappa-B signaling pathways, as well as osteoblast differentiation and various viral infection pathways. Differentially expressed genes, including intercellular adhesion molecule 1 (ICAM1), 6-phosphofructo-2-kinase, cyclin-dependent kinase inhibitor 1A, interleukin 1 receptor antagonist, integrin alpha IIb, and myosin light chain 9 were more upregulated in the SX group than in the SR group. Quantitative proteomics identified 723 differential proteins associated with the disease and 788 differential proteins between the SX and SR groups. Notable proteins such as myeloperoxidase, cluster of differentiation 14, macrophage simulating 1 (MST1), and Ras homolog enriched in brain may serve as characteristic proteins of the SX group. By integrating transcriptomic and proteomic data, 45 associated differential molecules involved in platelet activation, pathogenic intestinal flora infection, glycolysis/gluconeogenesis, and T-cell receptor signaling pathways were identified in patients with AS compared to healthy controls. Additionally, ICAM1, MST1, C-X-C motif chemokine ligand 8 (CXCL8), suppressor of cytokine signaling 3 (SOCS3), and insulin-like growth factor binding protein 1 (IGFBP1) were detected in TCM syndromes by RT-qPCR and ELISA, showing upregulation in AS renal deficiency and blood stasis syndromes, which is consistent with the proteomic and transcriptomic results. CONCLUSIONS: ICAM1, MST1, CXCL8, SOCS3, and IGFBP1 were identified as biomarkers of renal deficiency and blood stasis syndrome in AS. This study provides a biological basis for the differential diagnosis of TCM syndromes in AS, offering new insights into Chinese medicine evidence and more precise Chinese medicine treatments for AS.

Humans↗

[Interaction of Helicobacter polyri and indomethacin in gastric mucosa injury of Balb/c mice].

OBJECTIVE: To investigate the interaction of Helicobacter pylori (Hp) and indomethacin in gastric mucosa injury of Balb/c mice. METHODS: Fifty specific pathogen free 6-week-old Balb/c mice were randomly divided into 5 groups: group A (n = 8, 25 mg/kg indomethacin was injected intraperitoneally every other day for 6 times, and 0.2 ml Hp culture containing 1 x 10(8) - 1 x 10(9) CFU/ml was inoculated intra-gastrically every other day for 6 times), B (n = 8, 1 x 10(8) - 1 x 10(9) CFU/ml Hp culture was inoculated intra-gastrically on the 1st, 2nd, and 3rd days, and since the 7th day 25 mg/kg indomethacin was injected intraperitoneally every other day for 6 tomes), group C (n = 9, 0.2 ml normal saline was inoculated intra-gastrically on the 1st, 2nd, and 3rd days and since the 7th day 25 mg/kg indomethacin was injected intraperitoneally every other day for 6 times), group D (n = 10, 1 x 10(8) - 1 x 10(9) CFU/ml Hp culture was inoculated intra-gastrically on the 1st, 2nd, and 3rd days, and since the 7th day 0.2 ml normal saline was injected intraperitoneally every other day for 6 times), and group E (n = 10, 0.2 ml normal saline was inoculated intra-gastrically on the 1st, 2nd, and 3rd days, then 0.2 ml normal saline was injected intraperitoneally since the 7th day every other day for 6 times). The mice were killed in the 4th week. The stomachs were observed morphologically. Tissues from gastric antrum underwent HE staining, silver staining, and urease examination. Rauws classification was used to grade the gastritis thus discovered. RESULTS: Two mice in group A, one mouse in group B and 2 mice in group C died. One mouse in group B was Hp silver staining negative. Twenty-six of the total 30 mice infected with Hp showed inflammation with an infection rate of 66.7%. Moderate to severe inflammatory reaction was seen in all 8 mice in group A with an average gastritis score of 6.38 and with Hp found in the epithelium. Two out of the 8 mice in group showed focal erosion. All mice in group B showed moderate inflammation and Hp in mucosa with an average gastritis score of 5.13. Focal erosion was seen in one mouse in group B. Light moderate inflammation was seen in all 9 mice in group C with an average gastritis score of 3.89. Mild inflammation was seen in all 10 mice in group D with an average gastritis score of 2.8. No erosion was found in groups C and D. No inflammation was seen in the mice in group E with an average gastritis score of 0.4. The differences between any 2 groups were all significant. CONCLUSION: Hp and indomethacin synergetically aggravate the gastric epithelial injury. Prior Hp infection may be a protective factor of indomethacin-induced gastritis to a certain degree.

Animals↗

Pharmacokinetic/pharmacodynamic relationships of antimicrobial drugs used in veterinary medicine.

The rise in incidence of antimicrobial resistance, consumer demands and improved understanding of antimicrobial action has encouraged international agencies to review the use of antimicrobial drugs. More detailed understanding of relationships between the pharmacokinetics (PK) of antimicrobial drugs in target animal species and their action on target pathogens [pharmacodynamics (PD)] has led to greater sophistication in design of dosage schedules which improve the activity and reduce the selection pressure for resistance in antimicrobial therapy. This, in turn, may be informative in the pharmaceutical development of antimicrobial drugs and in their selection and clinical utility. PK/PD relationships between area under the concentration time curve from zero to 24 h (AUC(0-24)) and minimum inhibitory concentration (MIC), maximum plasma concentration (C(max)) and MIC and time during which plasma concentrations exceed the MIC have been particularly useful in optimizing efficacy and minimizing resistance. Antimicrobial drugs have been classified as concentration-dependent where increasing concentrations at the locus of infection improve bacterial kill, or time-dependent where exceeding the MIC for a prolonged percentage of the inter-dosing interval correlates with improved efficacy. For the latter group increasing the absolute concentration obtained above a threshold does not improve efficacy. The PK/PD relationship for each group of antimicrobial drugs is 'bug and drug' specific, although ratios of 125 for AUC(0-24):MIC and 10 for C(max):MIC have been recommended to achieve high efficacy for concentration-dependent antimicrobial drugs, and exceeding MIC by 1-5 multiples for between 40 and 100% of the inter-dosing interval is appropriate for most time-dependent agents. Fluoroquinolones, aminoglycosides and metronidazole are concentration-dependent and beta-lactams, macrolides, lincosamides and glycopeptides are time-dependent. For drugs of other classes there is limited and conflicting information on their classification. Resistance selection may be reduced for concentration-dependent antimicrobials by achieving an AUC(0-24):MIC ratio of greater than 100 or a C(max):MIC ratio of greater than 8. The relationships between time greater than MIC and resistance selection for time-dependent antimicrobials have not been well characterized.

Animals↗

Efficacy of zymodemes of E. histolytica technique in an epidemiologic study and report of new zymodemes in Mexico.

OBJECTIVES: To determine the efficacy of zymodemes of E. histolytica technique in an epidemiologic study. To report the zymodemes for the first time described in Mexico. To report the main difficulties in the correct classification of zymodemes in this study. To describe the zymodemes identified in two evaluations done in 100 healthy individuals. DESIGN: A cross-sectional survey and a cohort of healthy persons. METHODS: We analyze the results of 1730 Robinson cultures performed in a cross-sectional survey done in the Municipality of Cadereyta, Queretaro, Mexico from October 1986 to August 1987. From positive cultures properly growth a Iysate was done and preserved in liquid nitrogen until the electrophoretic determination of 4 isoenzymes was done: EC 5.3.1.9. glucophosphate isomerase (GPI); EC 1.1.1.40 L-malate: NADP oxidoreductase (oxaloacetate decarboxylating) (ME); Ec 2.7.5.1 phosphoglucomutase (PGM); and EC 2.7.1.1 hexokinase (HK). RESULTS: Of 1730 cultures 289 (16.7%) developed trophozoites, in 100 (34.6%) was possible to make lysate and zymodeme. There were 67 ZNP, 3 mixtures (ZP and ZNP) and 30 ZP. There were two patterns for the first time described in Mexico (XVII and XVIII) and 30 strains had a pattern different from the 20 already described by Sargeaunt. Results observed in 100 individuals measured twice. [table: see text] There were 9 subjects in which zymodemes were isolated twice: at the first time 5 PZ and 4 NPZ, at the second time 1 PZ and 8 NPZ. At first time all 9 had negative serology and the second time one carrier of NPZ became positive. COMMENTS: In our study one tirth of Robinson cultures positive to trophozoites reached lysate. Efficacy of zymodemes and CPS is similar. We report for the first time in Mexico two non-pathogenic zymodemes (XVII and XVIII). We also report 30 zymodemes non-classified according to the standard proposed by Sargeaunt, one explanation for this feature is the possibility of zymodemes variability or new patterns. In endemic populations zymodeme pattern varies with time in asymptomatic carriers.

Animals↗

Two new Fusicoccum species from Acacia and Eucalyptus in Venezuela, based on morphology and DNA sequence data.

Botryosphaeria spp. are common endophytes of woody plants, and they also include some serious pathogens of Eucalyptus and Acacia species. Numerous anamorphs have been associated with Botryosphaeria, of which the species Fusicoccum are amongst the most common. Here, we characterize two new Fusicoccum species, isolated from Eucalyptus and Acacia trees in Venezuela, based on morphological features in culture and comparisons of DNA sequence data. The two taxa named Fusicoccum andinum and F. stromaticum spp. nov, reside in two well-supported clades (BS values = 100%) based on a combined data set of the ITS of the rDNA operon and translation elongation factor 1-alpha (EF1- alpha) gene sequences. The conidia of F. andinum are unusually large amongst Botryosphaeria anamorphs, and peripherally resemble those of B. mamane and B. melanops. F. stromaticum is characterized by large conidiomata in cultures, growth at 35 degrees C and slightly thickened conidial walls, which is different to most other Fusicoccum spp. No teleomorphs were observed for these fungi, but DNA sequence data show that they are anamorphs of Botryosphaeria.

Acacia↗

Diagnosis of pneumonia and monitoring of infection eradication.

Pneumonia can be classified as community-acquired (CAP) or hospital-acquired (nosocomial). Both are frequent infections that demand a great amount of medical resources. The diagnosis of CAP is based on clinical signs and the presence of a pulmonary infiltrate visible on chest radiograph. For practical purposes, CAP has been classified as typical, with an acute onset in which the most representative microorganism is Streptococccus pneumoniae, and atypical, with a subacute onset (Mycoplasma pneumoniae). Nevertheless, so far no studies have clearly demonstrated the utility of this classification in predicting the aetiology. Guidelines on CAP recommend associating the aetiology of CAP with comorbidity, age and severity. The microbiological diagnosis relies mainly on Gram stain and sputum culture, but this technique has disadvantages such as frequent contamination of the sample with oropharyngeal commensal flora, frequent sterile cultures associated with previous antibiotic treatment, and the fact that approximately 40% of patients are not able to expectorate. Other diagnostic techniques such as blood cultures, serological tests and fibreoptic bronchoscopy must be reserved for patients who are hospitalised, especially if they need admission to an intensive care unit. Compared with CAP, nosocomial pneumonia has major diagnostic problems due to the presence of other diseases able to mimic pneumonia and frequent bacterial colonisation of the lower respiratory tract. Most of the diagnostic techniques produce a high percentage of false-negative and false-positive results. This is especially true for ventilator-associated pneumonia. There is controversy over using a comprehensive aetiological work-up based on bronchoscopic techniques or only on quantitative culture of endotracheal aspiration. By contrast, there is consensus about the importance of the adequacy of empirical antibiotic treatment, since mortality rates are higher in patients who are inadequately treated. Once treatment of pneumonia has begun, it must be maintained for 48 to 72 hours because this is the minimum time to evaluate a clinical response. Antibacterial agents have to be adjusted according to microbiological findings. In nonresponding patients, pneumonia-related complications and the presence of multiresistant micro-organisms or non-covered pathogens must be ruled out.

Anti-Bacterial Agents↗

Aphid biology: expressed genes from alate Toxoptera citricida, the brown citrus aphid.

The brown citrus aphid, Toxoptera citricida (Kirkaldy), is considered the primary vector of citrus tristeza virus, a severe pathogen which causes losses to citrus industries worldwide. The alate (winged) form of this aphid can readily fly long distances with the wind, thus spreading citrus tristeza virus in citrus growing regions. To better understand the biology of the brown citrus aphid and the emergence of genes expressed during wing development, we undertook a large-scale 5' end sequencing project of cDNA clones from alate aphids. Similar large-scale expressed sequence tag (EST) sequencing projects from other insects have provided a vehicle for answering biological questions relating to development and physiology. Although there is a growing database in GenBank of ESTs from insects, most are from Drosophila melanogaster and Anopheles gambiae, with relatively few specifically derived from aphids. However, important morphogenetic processes are exclusively associated with piercing-sucking insect development and sap feeding insect metabolism. In this paper, we describe the first public data set of ESTs from the brown citrus aphid, T. citricida. The cDNA library was derived from alate adults due to their significance in spreading viruses (e.g., citrus tristeza virus). Over 5180 cDNA clones were sequenced, resulting in 4263 high-quality ESTs. Contig alignment of these ESTs resulted in 2124 total assembled sequences, including both contiguous sequences and singlets. Approximately 33% of the ESTs currently have no significant match in either the non-redundant protein or nucleic acid databases. Sequences returning matches with an E-value of < or = -10 using BLASTX, BLASTN, or TBLASTX were annotated based on their putative molecular function and biological process using the Gene Ontology classification system. These data will aid research efforts in the identification of important genes within insects, specifically aphids and other sap feeding insects within the Order Hemiptera.

Animals↗

[Nosocomial infection in a pediatric intensive care unit].

UNLABELLED: Patients in intensive care units (ICU) are 3 to 4 times more prone to nosocomial infection (NI) than patients in general wards owing to the severity of their pathology and the frequent use of invasive procedures. The aim of this study was to establish the incidence of NI in an ICU and the associated risk factors. PATIENTS AND METHODS: During 18 months, all patients with severity scores III and IV (Clinical Classification System) were studied, (n = 575). The admissions were mainly due to accidents (24.7%), neurological (19.1%), surgical (17.2%), respiratory (11.1%) and infectious (7.0%) disease. The mean duration of stay was 2.4 days. The mortality was 5.2%. The evaluation protocol of these patients included determination of the PRISM score, registration of every invasive procedure and daily search for clinical and laboratory signs of infection. NI was defined according to the criteria of the Centers for Disease Control. Both the intrinsic and extrinsic risk factors were analysed and in the statistical analysis the null hypothesis was rejected at the significance level of p < 0.05. RESULTS: The incidence of NI was 7.6%. The infections occurred in the respiratory tract in 20 patients, bloodstream in 8, genito-urinary tract in 2, central nervous system in 2, skin in 2, gastrointestinal tract in 2, eyes in 1 and surgical wound in 1. There were isolates in 60.6%. The mean duration of stay was longer in patients with NI (9.8 versus 1.9). The factors most closely associated with NI were higher PRISM scores, malnutrition, immunodeficiency failure of 2 or more organs, administration of antibiotic since admission or corticosteroids and simultaneous use of 3 or more invasive procedures. The risk of pneumonia was significantly increased in patients with mechanical ventilation and all the patients with bacteremia had central venous catheters. The mortality was higher in the group with NI (18.2%) than in the group without NI (4.4%). CONCLUSIONS: The incidence of NI is acceptable in our ICU. The most frequent location was the respiratory tract (52.6%). The pathogens most frequently isolated in this ICU were Gram negative rods. The risk of NI increased in more debilitated patients with more severe disease who were administered antibiotic or corticosteroids and submitted to more invasive procedures.

Adolescent↗

Emphysematous pyelonephritis: clinicoradiological classification, management, prognosis, and pathogenesis.

BACKGROUND: Emphysematous pyelonephritis (EPN) is a rare, severe gas-forming infection of renal parenchyma and its surrounding areas. The radiological classification and adequate therapeutic regimen are controversial and the prognostic factors and pathogenesis remain uncertain. OBJECTIVES: To elucidate the clinical features, radiological classification, and prognostic factors of EPN; to compare the modalities of management (ie, antibiotic treatment alone, percutaneous catheter drainage combined with antibiotic treatment, or nephrectomy) and outcome among the various radiological classes of EPN; and to clarify the gas-forming mechanism and pathogenesis of EPN by gas analysis and pathological findings. PATIENTS AND METHODS: Forty-eight EPN cases from our institution were enrolled between August 1,1989, and November 30, 1997. According to the radiological findings on computed tomographic scan, they were classified into the following classes: (1) class 1: gas in the collecting system only; (2) class 2: gas in the renal parenchyma without extension to extrarenal space; (3) class 3A: extension of gas or abscess to perinephric space; class 3B: extension of gas or abscess to pararenal space; and (4) class 4: bilateral EPN or solitary kidney with EPN. The clinical manifestations, management, and outcome were compared. The gas contents of specimens from 6 patients were analyzed. The pathological findings from 8 patients who received nephrectomy were reviewed. The statistical methods consisted of the Fisher exact test (2 tailed) for categorical variables and Wilcoxon rank sum test for continuous variables to test the predictors of poor prognosis. RESULTS: Forty-six patients (96%) had diabetes mellitus, and 10 (22%) of the 46 also had urinary tract obstruction in the corresponding renoureteral unit. The other 2 nondiabetic patients (4%) had severe hydronephrosis. Twenty-one (72%) of the 29 patients with diabetes mellitus also had a glycosylated hemoglobin A(1c) level higher than 0.08. Escherichia coli (69%) and Klebsiella pneumoniae (29%) were the most common pathogens. The mortality rate in patients who received antibiotic treatment alone was 40% (2 of 5 patients). The success rate of management by percutaneous catheter drainage (PCD) combined with antibiotic treatment was 66% (27 of 41 patients). In classes 1 and 2 EPN, all the patients who were treated using a PCD or ureteral catheter combined with antibiotic treatment survived. In extensive EPN (classes 3 and 4), 17 (85%) of the 20 patients with fewer than 2 risk factors (ie, thrombocytopenia, acute renal function impairment, disturbance of consciousness, or shock) were successfully treated using PCD combined with antibiotic treatment; and the patients with 2 or more risk factors had a significantly higher failure rate than those with no or only 1 risk factors (92% vs 15%, P<.001). Eight of the 14 patients who had an unsuccessful treatment using a PCD underwent subsequent nephrectomy, 7 of whom survived. Only 2 patients were managed by direct nephrectomy and survived. The overall success rate of nephrectomy was 90% (9 of 10 patients). The total mortality was 18.8% (9 of 48 patients). Five of the 6 gas samples contained hydrogen (average, 12.8%), and all had carbon dioxide (average, 14.4%). The pathological findings from 8 of 10 who underwent nephrectomy revealed poor perfusion in most cases (ie, infarction, 5 patients; vascular thrombosis, 3 patients; and arteriosclerosis and/or glomerulosclerosis, 4 patients). CONCLUSION: Acute renal infection with E coli or K pneumoniae in patients with diabetes mellitus and/or urinary tract obstruction is the cornerstone for the development of EPN. Mixed acid fermentation of glucose by Enterobacteriaceae is the major pathway of gas formation. For localized EPN (classes 1 and 2), PCD combined with antibiotic treatment can provide a good outcome. (ABSTRACT TRUNCATED)

Adult↗

Clinical course, pathological correlations, and outcome of biopsy proved inflammatory demyelinating disease.

BACKGROUND: A pathological classification has been developed of early active multiple sclerosis (MS) lesions that reveals four patterns of tissue injury: I-T cell/macrophage associated; II-antibody/complement associated; III-distal oligodendrogliopathy, and IV-oligodendrocyte degeneration in the periplaque white matter. Mechanisms of demyelination in early MS may differ among the subgroups. Previous studies on biopsied MS have lacked clinicopathological correlation and follow up. Critics argue that observations are not generalisable to prototypic MS. OBJECTIVE: To describe the clinicopathological characteristics of the MS Lesion Project biopsy cohort. METHODS: Clinical characteristics and disability of patients with pathologically confirmed inflammatory demyelinating disease (excluding ADEM) classified immunopathologically (n = 91) and patients from the Olmsted County MS prevalence cohort (n = 218) were determined. RESULTS: Most patients who underwent biopsy and had pathologically proved demyelinating disease ultimately developed definite (n = 70) or probable (n = 12) MS (median follow up 4.4 years). Most had a relapsing remitting course and 73% were ambulatory (EDSS < or =4) at last follow up. Nine patients remained classified as having an isolated demyelinating syndrome at last follow up. Patients with different immunopathological patterns had similar clinical characteristics. Although presenting symptoms and sex ratios differed, the clinical course in biopsy patients was similar to the prevalence cohort. Median EDSS was <4.0 in both cohorts when matched for disease duration, sex, and age. CONCLUSIONS: Most patients undergoing biopsy, who had pathologically confirmed demyelinating disease, were likely to develop MS and remain ambulatory after a median disease duration of 4.4 years. The immunopathological patterns lacked specific clinical correlations and were not related to the timing of the biopsy. These data suggest that pathogenic implications derived largely from MS biopsy studies may be extrapolated to the general MS population.

Adolescent↗

Comparison of methods for discrimination between strains of Listeria monocytogenes from epidemiological surveys.

Total cellular DNA from 28 strains of Listeria monocytogenes isolated from food implicated in food-borne illness and from patients with listeriosis was digested with the restriction endonucleases HindIII, HaeIII, and EcoRI. Following agarose gel electrophoresis, the fragments were subjected to Southern blot hybridization with a digoxigenin-labeled cDNA probe transcribed from Escherichia coli 16S and 23S rRNA. The patterns of bands from genomic (DNA fingerprints) and rDNA fingerprints (ribotypes) were used for classifying L. monocytogenes strains, and the resulting subtypes were compared with serotyping and multilocus enzyme electrophoresis classification schemes. A total of 15 distinct and identical groups were obtained when genomic DNA was digested with either HindIII or HaeIII. The most discriminating enzyme for ribotyping of strains was EcoRI, which divided the 28 strains of L. monocytogenes into 6 ribotype groups. DNA fingerprinting and ribotyping differentiated L. monocytogenes from other Listeria spp., including L. ivanovii, L. welshimeri, and L. innocua as well as the lactic acid bacteria Lactococcus lactis subsp. lactis and subsp. cremoris. L. monocytogenes strains isolated from four independent food-borne illness incidents were analyzed by all typing methods. Patient and product isolates were not distinguishable by serotyping, ribotyping, or multilocus enzyme electrophoresis. DNA fingerprinting was the only method capable of differentiating these strains, or conversely, of proving relatedness of patient-product pairs of isolates. This method was a relatively simple, sensitive, reproducible, and highly discriminating method for epidemiological tracking of L. monocytogenes implicated in food-borne illness.

Animals↗

[Bovine diarrhea virus: an update].

Bovine Viral Diarrhea Virus (BVDV) is a pathogen of cattle, member of the family Flaviviridae, genus pestivirus, which also includes Classical Swine Fever Virus (CSFV, or hog cholera virus), and Border Disease Virus of sheep (BDV). It causes important economical losses associated mainly with reproductive failure. Pestiviruses are small enveloped viruses, with a diameter of about 40 nm. The nucleocapsid is probably icosahedral . The genome consists of a single stranded positive RNA, encoding approximately 430 kD of proteic product. Genetic expression consists of the synthesis of a polyprotein which is co- and post-translationally processed. According to its behavior "in vitro" two biotypes can be distinguished: non cytopathic (ncp) and cytopathic (cp), most probably derived from the ncp through mutations and/or recombination. BVDV is able to cross the placenta and infect the fetus, causing a variety of problems, from fetal death to the birth of a persistently infected (P) calf, according to the fetal age at the time of infection. PI animals are immunotolerant to the virus and shed it in all secretions. Only the ncp biotype has been isolated from PI animals. The superinfection of a PI animal with a cp strain causes mucosal disease, always fatal. Outbreaks of a severe, sometimes hemorrhagic disease, caused by ncp BVDV, have occurred in Canada and USA since 1993. Genomic and serological differences between the "traditional" strains and the viruses isolated from these outbreaks led to the division of BVDV in subtypes I and II, both including cp and ncp strains. Analyses of the non coding 5'-UTR zone of the genome of pestiviruses from different species (bovine, ovine, porcine) suggest that there are at least 3 genotypes within the genus. A new classification of these viruses, based on genomic sequence instead of species of origin, has been proposed. Genomic heterogeneity exists in the BVDV genome, which presents 3 hypervariable zones, 2 of them in the major neutralizing protein. In Argentina prevalence of BVDV antibodies in cattle population is 70%, and the prevalence of persistent infections is around 1%.

Abortion, Veterinary↗

Genotyping of hepatitis B virus in Malaysia based on the nucleotide sequence of preS and S genes.

Hepatitis B virus (HBV) has been classified into eight genotypes, designated A-H. These genotypes are known to have distinct geographic distributions. The clinical importance of genotype-related differences in the pathogenicity of HBV has been revealed recently. In Malaysia, the current distribution of HBV remains unclear. The aim of this study was to determine the genotypes and subtypes of HBV by using PCR, followed by DNA sequencing, as well as to analyse the mutations in the immunodominant region of preS and S proteins. The S gene sequence was determined from HBV DNA of four apparently healthy blood donors' sera and three sera from asymptomatic chronic hepatitis B carriers. Of this batch of sera, the preS gene sequence was obtained from HBV DNA from three out of the four blood donors and two out of the three chronic carriers. Due to insufficient sera, we had to resort to using sera from another blood donor to make up for the sixth DNA sequence of the preS gene. Based on the comparative analysis of the preS sequences with the reported sequences in the GenBank database, HBV DNA from two normal carriers was classified as genotype C. Genotype B was assigned to HBV from one blood donor and two hepatitis B chronic carriers, whereas HBV of one chronic carrier was of genotype D. Based on the S gene sequences, HBV from three blood donors was of genotype C, that of one blood donor and one chronic carrier was of genotype B, and the remaining, of genotype D. In the five cases where both preS and S gene sequences were determined, the genotypes assigned based on either the preS or S gene sequences were in concordance. The nature of the deduced amino acid (aa) sequences at positions 125, 127, 134, 143, 159, 161 and 168 of the S gene enabled the classification of these sequences into subtypes, namely, adrq+, adw2 and ayw2. The clustering of our DNA sequences into genotype groups corresponded to their respective subtype, that is, adw2 in genotype B, adrq in genotype C and ayw in genotype D. Analysis of the point mutations revealed that five of the sequences contained aa substitutions at immunodominant epitopes involved in B or/and T cell recognition. In conclusion, despite the low numbers of samples studied, due to budget constraints, these data are still worthwhile reporting, as it is important for the control of HBV infections. In addition, the genotype and mutational data obtained in this study may be useful for designing new treatment regimes for HBV patients.

Amino Acid Sequence↗

[Distribution of species of the genus Listeria].

Within the classification of different Listeria species according to present knowledge, this study investigates the sources and distribution of both the known "classical" species of Listeria as well as the recently added species: L. monocytogenes, L. innocua, L. ivanovii, L. welshimeri, L. seeligeri, L. grayi and L. murrayi. For this purpose 573 isolates from the environment, food, healthy carriers and patients suffering from listeriosis were selected out of a total of approximately 6000 strains originating from all parts of the globe which are maintained at the Listeria Culture Collection of the Institute of Hygiene, Würzburg. The selection was made according to the criterium of widest possible geographic distribution. The results indicate the environment to be the natural reservoir of all of the 7 'new' Listeria species. Healthy animal carriers harbour in their intestinal tract all species of Listeria with the exception of L. murrayi, whilst in the excreta of healthy individuals only the species L. monocytogenes, L. ivanovii, and L. innocua were found. Identification of strains from pathological specimens of human and animal origin resulted invariably in the finding of L. monocytogenes or L. ivanovii. L. grayi (7 strains) was found sporadically in Europe and in the USA, whereas L. murrayi (9 strains) has been isolated only in the USA. 26 of 28 so far known strains of L. welshimeri originated from the USA, and only 2 strains of this species were found in Europe. L. seeligeri (80 strains) was identified among European isolates, L. innocua, however, in both USA and Europe. L. ivanovii occurs in Australia, Europe and the USA. L. monocytogenes is of global distribution. Table 1 presents a survey of species, serovariety and origin of the 573 isolates. As both pathogenic and non pathogenic listeria strains are found in the human environment, it is necessary to identify each isolate appropriately, particularly in view of the elucidation of the rather obscure epidemiology of human listeriosis.

Animals↗