Magnetic Levitation System Isolates and Purifies Airborne Viruses

Detection of viable viruses in the air is critical in order to determine the level of risk associated with the airborne diffusion of viruses. Different methods have been developed for the isolation, purification, and detection of viable airborne viruses, but they require an extensive processing time and often present limitations including low physical efficiency (i.e., the amount of collected viruses), low biological efficiency (i.e., the number of viable viruses), or a combination of all. To mitigate such limitations, we have employed an efficient technique based on the magnetic levitation (Maglev) technique with a paramagnetic solution and successfully identified distinct variations in levitation and density characteristics among bacteria (Escherichia coli), phages (MS2), and human viruses (SARS-CoV-2 and influenza H1N1). Notably, the Maglev approach enabled a significant enrichment of viable airborne viruses in air samples. Furthermore, the enriched viruses obtained through Maglev exhibited high purity, rendering them suitable for direct utilization in subsequent analyses such as reverse transcription-polymerase chain reaction (RT-PCR) or colorimetric assays. The system is portable, easy to use, and cost-efficient and can potentially provide proactive surveillance data for monitoring future outbreaks of airborne infectious diseases and allow for the induction of various preventative and mitigative measures.

Characterizing the Role of Calcium Sensing Receptor in the Progression of Obesity-Mediated Aggressive Prostate Cancer Phenotype

Obesity increases the risk of advanced prostate cancer (PCa). The calcium sensing receptor (CaSR) has been shown to be responsive to obesity-mediated cytokines and is upregulated in metastatic PCa. This study used a novel in vitro approach, involving the exposure of PCa cells to sera, from obese or normal weight males, and to CaSR inhibitor NPS-2143. Cell viability was determined using MTT assay. MMP-9 activity and invasion were assessed using zymography and invasion chambers, respectively. Microscopy was used to visualize EMT proteins. qRT-PCR and immunoblot analysis were used to quantify changes in genes and proteins important for tumorigenesis. Exposure to obese sera increased the proliferation, and the invasive capacity of PCa cells and de-localized epithelial-mesenchymal transition markers, which were attenuated with CaSR inhibition. Exposure to obese sera upregulated mRNA expression of PTHrP and protein expression of COX-2, IL-6, and CaSR. Inhibition of CaSR downregulated the mRNA expression of PTHrP and RANK, and protein expression of pERK and TNF-α. Obesity was shown to increase invasion and upregulate the expression of genes and proteins involved in PCa tumorigenesis. CaSR inhibition downregulated the expression of several of these factors. Thus, CaSR is a potentially important protein to target in obesity-mediated PCa progression.

Pneumocystis jirovecii in Patients With Cystic Fibrosis: A Review

Pneumocystis pneumonia (PCP) remains the most frequent AIDS-defining illness in developed countries. This infection also occurs in non-AIDS immunosuppressed patients, e.g., those who have undergone an organ transplantation. Moreover, mild Pneumocystis jirovecii infections related to low pulmonary fungal burden, frequently designated as pulmonary colonization, occurs in patients with chronic pulmonary diseases, e.g., cystic fibrosis (CF). Indeed, this autosomal recessive disorder alters mucociliary clearance leading to bacterial and fungal colonization of the airways. This mini-review compiles and discusses available information on P. jirovecii and CF. It highlights significant differences in the prevalence of P. jirovecii pulmonary colonization in European and Brazilian CF patients. It also describes the microbiota associated with P. jirovecii in CF patients colonized by P. jirovecii. Furthermore, we have described P. jirovecii genomic diversity in colonized CF patients. In addition of pulmonary colonization, it appears that PCP can occur in CF patients specifically after lung transplantation, thus requiring preventive strategies. In other respects, Pneumocystis primary infection is a worldwide phenomenon occurring in non-immunosuppressed infants within their first months. The primary infection is mostly asymptomatic but it can also present as a benign self-limiting infection. It probably occurs in the same manner in CF infants. Nonetheless, two cases of severe Pneumocystis primary infection mimicking PCP in CF infants have been reported, the genetic disease appearing in these circumstances as a risk factor of PCP while the host-pathogen interaction in older children and adults with pulmonary colonization remains to be clarified.

Evidence of the Red-Queen Hypothesis from Accelerated Rates of Evolution of Genes Involved in Biotic Interactions in Pneumocystis

Pneumocystis species are ascomycete fungi adapted to live inside the lungs of mammals. These ascomycetes show extensive stenoxenism, meaning that each species of Pneumocystis infects a single species of host. Here, we study the effect exerted by natural selection on gene evolution in the genomes of three Pneumocystis species. We show that genes involved in host interaction evolve under positive selection. In the first place, we found strong evidence of episodic diversifying selection in Major surface glycoproteins (Msg). These proteins are located on the surface of Pneumocystis and are used for host attachment and probably for immune system evasion. Consistent with their function as antigens, most sites under diversifying selection in Msg code for residues with large relative surface accessibility areas. We also found evidence of positive selection in part of the cell machinery used to export Msg to the cell surface. Specifically, we found that genes participating in glycosylphosphatidylinositol (GPI) biosynthesis show an increased rate of nonsynonymous substitutions (dN) versus synonymous substitutions (dS). GPI is a molecule synthesized in the endoplasmic reticulum that is used to anchor proteins to membranes. We interpret the aforementioned findings as evidence of selective pressure exerted by the host immune system on Pneumocystis species, shaping the evolution of Msg and several proteins involved in GPI biosynthesis. We suggest that genome evolution in Pneumocystis is well described by the Red-Queen hypothesis whereby genes relevant for biotic interactions show accelerated rates of evolution.

AIDS-related Pneumocystis jirovecii genotypes in French Guiana

The study described Pneumocystis jirovecii (P. jirovecii) multilocus typing in seven AIDS patients living in French Guiana (Cayenne Hospital) and seven immunosuppressed patients living in Brest, metropolitan France (Brest Hospital). Archival P. jirovecii specimens were examined at the dihydropteroate synthase (DHPS) locus using a PCR-RFLP technique, the internal transcribed spacer (ITS) 1 and ITS 2 and the mitochondrial large subunit rRNA (mtLSUrRNA) gene using PCR and sequencing. Analysis of typing results were combined with an analysis of the literature on P. jirovecii mtLSUrRNA types and ITS haplotypes. A wild DHPS type was identified in six Guianese patients and in seven patients from metropolitan France whereas a DHPS mutant was infected in the remaining Guianese patient. Typing of the two other loci pointed out a high diversity of ITS haplotypes and an average diversity of mtLSUrRNA types in French Guiana with a partial commonality of these haplotypes and types described in metropolitan France and around the world. Combining DHPS, ITS and mtLSU types, 12 different multilocus genotypes (MLGs) were identified, 4 MLGs in Guianese patients and 8 MLGs in Brest patients. MLG analysis allows to discriminate patients in 2 groups according to their geographical origin. Indeed, none of the MLGs identified in the Guianese patients were found in the Brest patients and none of the MLGs identified in the Brest patients were found in the Guianese patients. These results show that in French Guiana (i) PCP involving DHPS mutants occur, (ii) there is a diversity of ITS and mtLSUrRNA types and (iii) although partial type commonality in this territory and metropolitan France can be observed, MLG analysis suggests that P. jirovecii organisms from French Guiana may present specific characteristics.

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa)

The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites) with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

Prevalence of colonisation and genotypic characterisation of Pneumocystis jirovecii among cystic fibrosis patients in Spain

Pneumocystis jirovecii colonisation may occur among cystic fibrosis (CF) patients because of their underlying pulmonary disease. A wide epidemiological analysis was performed among CF patients from Spain to assess the prevalence of P. jirovecii colonisation and the distribution of different genotypes. P. jirovecii was identified by nested PCR targeting the mitochondrial large-subunit rRNA gene from sputum samples or oropharyngeal washes. The genotype was determined by direct sequencing. The prevalence of P. jirovecii colonisation among 88 consecutive CF patients was 21.5%. The polymorphisms identified were 85C/248C (45.4%), 85T/248C (27.2%) and 85A/248C (18.1%); in one case, a mix of genotypes was found. Colonisation was more frequent in subjects aged < 18 years (25.5% vs. 15.1%). Among the patients studied, 20.8% received treatment with azithromycin; all of these patients were colonised with P. jirovecii, but none developed Pneumocystis pneumonia (PcP) during a 1-year follow-up period. Concordance in the colonisation status of siblings suggested a common source of infection or person-to-person transmission.

Evidence of Helicobacter sp. in dental plaque of captive dolphins (Tursiops gephyreus)

Gastrointestinal lesions have been extensively reported in wild and captive marine mammals. However, their etiology remains unclear. In humans and other animals, chronic gastritis and peptic ulcers have been associated with Helicobacter sp. Therefore, the aim of our study was to investigate the presence of Helicobacter sp. in the gastric juice, dental plaque, and saliva of marine mammals living in a controlled environment. Five dolphins (Tursiops gephyreus), one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), three sea lions (Otaria flavescens), two elephant seals (Mirounga leonina), and two fur seals (Arctocephalus australis) were studied. Saliva, dental plaque, and gastric juice samples were examined for Helicobacter sp. using polymerase chain reaction. None of the gastric juice or saliva samples were positive for Helicobacter sp. However, Helicobacter sp. DNA was detected in dental plaque from two dolphins, suggesting the oral cavity might be a reservoir of this bacterium.

Acute, symptomatic atrial fibrillation after sildenafil citrate therapy in a patient with hypertrophic obstructive cardiomyopathy

This case report describes a patient with hypertrophic cardiomyopathy who developed symptomatic atrial fibrillation on two occasions after ingesting sildenafil citrate (Viagra). Sildenafil citrate should be withheld or used with extreme caution in persons with hypertrophic obstructive cardiomyopathy.

Comparative study of beans from vine and bush type of vegetative growth. Effect of storage on cell wall components as factors in increasing cooking time

Four samples each of black beans representing two types of vegetative growth were collected from farmers' fields in four locations in Guatemala. Soon after collection, samples were stored at 4 degrees and 38 degrees C at ambient relative humidity and subsamples were withdrawn at 0, 45, 90 and 135 days of storage for determination of water absorption, cooking time and analysis of neutral- and acid detergent fiber, cellulose, hemicellulose and lignin. The fiber fraction analysis were done on samples of 0, 45 and 90 days of storage. Water absorption for all 4 samples of the bush type was similar at both storage T, however the samples stored at 38 degrees C and at 135 days absorbed more water than when stored at 4 degrees C. The 4 vine types of beans showed different water absorption rates, with two showing patterns similar to those beans of the bush type and two which did absorbed water at a very slow rate. For both types of beans stored at 4 degrees C, cooking time decreased from 0 to 135 days of storage. On the other hand for all bean samples of the two types cooking time increased when stored at 38 degrees C. Analysis of variance showed highly significant effects due to plant type, days of storage, temperature and locality, and for some interactions. Analysis of variance of the fiber fractions showed high significant differences for days of storage for NDF, ADF, cellulose, hemicellulose, and lignin. Plant type gave significant differences for cellulose and hemicellulose. Highly significant differences for hemicellulose were found for the interactions of type x days, type x temperature, locality x type, and type x days x temperature. The rate of synthesis of the 5 fractions were calculated by simple regression analysis. For the bush type of beans some synthesis occurred at 4 degrees C, but it was enhanced when stored at 38 degrees C. For vine type of beans at 4 degrees C relative high rates of synthesis were observed, which were higher at 38 degrees C for NDF, hemicellulose and lignin. Cooking time and fiber fraction contents were subjected to regression analysis. The correlations at 38 degrees C were higher than at 4 degrees C for all fractions for both types of beans, but statistical significance was obtained only for NDF, ADF and cellulose for vine type of beans. These data show therefore that synthesis of cell wall structure fractions, and not only lignin formation, are responsible for the increase in cooking time observed upon storage at high temperature.

Idiosyncratic pacing with a commercial pacing system analyzer

An idiosyncratic response of the Medtronic AV Pacing System Analyzers (models 5311 [unipolar] and 5311B [bipolar]) during high output AAI pacing is reported. Using the bipolar analyzer with unipolar cables and a 2734 adaptor, ventricular capture was noted during high output AAI pacing when the ground was displaced from the patient. Using the unipolar analyzer with bipolar cables also resulted in ventricular capture with high output AAI pacing. Implanting physicians should be aware of this phenomenon to avoid false conclusions.

Epidemiology of HTLV-I infection in Spain. HTLV Spanish Study Group

BACKGROUND

The human T-lymphotropic virus type I (HTLV-I) has been implicated in the genesis of tropical spastic paraparesis (TSP), adult T-cell lymphoma (ATL), and some cases of uveitis, subacute arthropathies, chronic dermatitis and lymphocytic alveolitis. The virus is endemic in some areas of the Caribbean basin, Japan, subSaharan Africa, Central and South America, Middle East and Melanesia. Given that HTLV-I is transmitted through similar ways to HIV, screening in blood donors is recommended in some countries.

MATERIALS AND METHODS

The clinical, epidemiological and virological characteristics of 27 patients with HTLV-I infection were identified in Spain up to September 1995.

RESULTS

Eighteen cases were Spanish natives and 9 were immigrants from endemic areas. Fifteen were male and 12 were female. The majority (12/18; 66.7 percent) of subjects born in Spain had resided in endemic areas or had had sexual partners from these regions. Four patients had TSP, three had ATL and one developed lymphomatous granulomatosis and T-cell lymphoma. The remaining HTLV-I subjects were asymptomatic at the time of diagnosis. Four cases were identified from screening of blood donors.

CONCLUSION

HTLV-I is present in Spain, affecting natives and, less frequently, immigrants from endemic areas. Both neurological and lymphoproliferative diseases have been recognized in a quarter of patients.

Alterations in soluble intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in hemodialysis patients

Hemodialysis (HD) patients can develop acute reactions during treatment as well as increased long-term susceptibility to infections and malignancies. Abnormalities in leukocyte adhesion may contribute to these processes. Recently, serum levels of soluble adhesion molecules have been detected in circulating blood of normal subjects and in patients with chronic renal failure. We studied the effects of a single dialysis session with new cuprophane membrane on the soluble (s) form of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), two adhesion molecules with a variety of immunologic roles. Significant elevations in both sICAM-1 (523 +/- 61 v 304 +/- 45 [SEM] ng/mL, P < 0.05) and sVCAM-1 (2,055 +/- 270 v 1,189 +/- 149 ng/mL, P < 0.05) were observed in HD patients at baseline compared with controls. Both sICAM-1 and sVCAM-1 levels decreased after a 3-hour HD session (P < 0.001). Early in HD, sICAM-1 levels, though lower than predialysis, were elevated in the exit line of the dialyzer compared with entrance (339 +/- 64 v 259 +/- 53 ng/mL, P < 0.001), whereas sVCAM-1 was decreased on the exit line compared with entrance (639 +/- 90 v 932 +/- 92 ng/mL, P < 0.001). Because ICAM-1 and VCAM-1 are important for many leukocyte functions, alterations in serum levels of sICAM-1 and sVCAM-1 may play a role in the immunologic consequences of uremia and HD treatment.

Chronic sinusitis in children

Chronic sinusitis is now recognized as a common clinical syndrome in adults and children. An astute physician can diagnose chronic sinusitis during the physical exam, but fiber-optic rhinoscopy and x-rays (plain films and computerized tomography) are required to confirm this diagnosis, evaluate the severity of the sinusitis and determine follow-up treatment. Appropriate treatment plans are prescribed for an adequate duration to eliminate infection and inflammatory components of the pathologic process of the sinuses involved. Antibiotics, decongestants, and inhaled or systemic corticosteroids are required in the treatment of patients with chronic sinusitis. When combined with close clinical follow-up, successful resolution is expected. Surgical intervention is needed in the medically refractory and symptomatic cases, or when complications develop. The frequent diagnosis of chronic sinusitis in the past 1-2 decades is, in part, due to the enhanced awareness and clinical skills of the treating physicians, but other concerns about environmental influences such as frequent respiratory tract infections in childhood and air quality issues are considered potentially important.

Pneumocystis carinii pneumonia in patients without predisposing illnesses. Acute episode and follow-up of five cases

Pneumocystis carinii pneumonia (PCP) is described almost exclusively in immunocompromised hosts. This report describes our experience with acute episodes and the follow-up of five patients with PCP who had no known predisposing conditions. The average follow-up period was 3.6 years (range, 2.6 to 4 years). Lymphocyte subpopulations (CD4, CD8, and CD4:CD8), serum immunoglobulins (IgG, IgM, and IgA), and serologic studies for human immunodeficiency virus were carried out on all patients at least twice, both at the beginning and the end of the follow-up. None of the patients presented compatible data with AIDS or any other identifiable risk factors. We conclude that PCP can occur in patients who apparently do not have immunosuppression.

Treatment of presumed bacterial pneumonia in ambulatory children

In a prospective, randomized, open study, a combination of trimethoprim and rifampin (TMP/R) 20 mg/kg/day was compared with ampicillin (AMP) 150 mg/kg/day, both given orally twice daily for 10 days, for the treatment of 60 children who had mild community-acquired pneumonia. The control group comprised 112 healthy children. The overall duration of the disease was 8.5 +/- 3.6 days in the TMP/R group vs 6.0 +/- 1.1 days in the AMP group. Fever persisted for 7.0 +/- 1.8 days in the TMP/R-treated patients vs 5.2 +/- 1.0 days in the AMP-treated patients. At the end of the 10 days, nasopharyngeal cultures were negative in all patients in the AMP group and in 25 of the 30 patients in the TMP/R group. These five patients were clinical and microbiologic failures. We conclude that in infants and children with mild community-acquired pneumonia, treatment with AMP for 10 days is more effective than treatment with a combination of TMP/R for clinical cure and eradication of bacterial pathogens.

Government relations: too important to be left to the politicians

Politics have changed. The part-time citizen legislator has been replaced by the professional politician, and legislative decisions are being made more by coalitions than by a few powerful legislators. Health care is increasingly regulated by the government. As a result, it is necessary for the hospital industry to take an active role in the legislative process.

Antibiotic concentrations in pus and bone of children with osteomyelitis

Pharmacologic data are presented on 39 children treated for osteomyelitis with one of the following antibiotics: methicillin, dicloxacillin, cephaloridine, or cefazolin. The concentrations of drug in pus and bone were correlated with serum concentrations, with the susceptibilities of Staphylococcus aureus strains isolated from the patients, and with the degree of drug protein-binding. The penetration of the antibiotics into pus and bone was similar for the two penicillins and for the two cephalosporins despite the disparate protein-binding affinities of these drugs. The agents attained concentrations in tissues that were at least several fold, and often more than tenfold, greater than the MIC and MBC values of the S. aureus stains. These data provide a basis for selection of antimicrobial agents for treatment of osteomyelitis.

Distinct reovirus-like agents associated with acute infantile gastroenteritis

Human reovirus-like particles were found by electron microscopy in the stools of 25% of 71 infants and young children hospitalized with acute gastroenteritis in Mexico between December 1976 and April 1977. The virus was also identified by the electrophoresis patterns of its ribonucleic acid upon disruption of partially purified particles. This technique is as reliable as electron microscopy but less laborious, and could become a routine diagnostic procedure. The electrophoretic patterns of viral ribonucleic acid from different cases suggest that there are at least two different reovirus-like agents associated with infantile gastroenteritis.