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1.
J Phycol ; 60(3): 724-740, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38698553

ABSTRACT

Chlainomonas (Chlamydomonadales, Chlorophyta) is one of the four genera of snow algae known to produce annual pink or red blooms in alpine snow. No Chlainomonas species have been successfully cultured in the laboratory, but diverse cell types have been observed from many field-collected samples, from multiple species. The diversity of morphologies suggests these algae have complex life cycles with changes in ploidy. Over 7 years (2017-2023), we observed seasonal blooms dominated by a Chlainomonas species from late spring through the summer months on a snow-on-lake habitat in an alpine basin in the North Cascade Mountains of Washington, USA. The Bagley Lake Chlainomonas is distinct from previously reported species based on morphology and sequence data. We observed a similar collection of cell types observed in other Chlainomonas species, with the addition of swarming biflagellate cells that emerged from sporangia. We present a life cycle hypothesis for this species that links cell morphologies observed in the field to seasonally available habitat. The progression of cell types suggests cells are undergoing both meiosis and fertilization in the life cycle. Since the life cycle is the most fundamental biological feature of an organism, with direct consequences for evolutionary processes, it is critical to understand how snow algal life cycles will influence their responses to changes in their habitat driven by climate warming. For microbial taxa that live in extreme environments and are difficult to culture, temporal field studies, such as we report here, may be key to creating testable hypotheses for life cycles.


Subject(s)
Chlorophyta , Snow , Chlorophyta/physiology , Chlorophyta/growth & development , Washington , Seasons , Life Cycle Stages , Lakes
2.
Water Sci Technol ; 83(11): 2714-2723, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34115625

ABSTRACT

The textile industry is one of the main generators of industrial effluent due to the large volumes of water containing a wide variety of pollutants, including dyes. Thus, the present study aimed to remove the Disperse Blue 56 dye present in synthetic textile effluent using ionic flocculation through surfactant flocs produced from animal/vegetable fat, assessing the system at different surfactant concentrations and temperatures. The process kinetics, adsorption mechanism and equilibrium were evaluated. The results show that the kinetics was better described by the Elovich model when compared to pseudo-first order and pseudo-second order models, indicating that chemical adsorption occurs during the process. The study of the adsorption mechanism obtained lower outer layer diffusivities than their intra-particle counterparts, demonstrating that the dye transport to the surfactant floc is controlled through the outer layer. The Langmuir isotherm was suitable for equilibrium data and the separation factor calculated showed that the isotherm is classified as favorable. Dye removal efficiency reached 87% after 360 minutes of contact between the effluent and the surfactant flocs, indicating that ionic flocculation is an efficient alternative in the treatment of textile effluent containing disperse dye.


Subject(s)
Water Pollutants, Chemical , Water Purification , Adsorption , Anthraquinones , Coloring Agents , Flocculation , Hydrogen-Ion Concentration , Kinetics , Textile Industry , Textiles , Water Pollutants, Chemical/analysis
3.
FEMS Microbiol Ecol ; 99(11)2023 10 17.
Article in English | MEDLINE | ID: mdl-37675994

ABSTRACT

Snow algal blooms frequently occur throughout alpine and polar environments during spring and summer months; however, our understanding of bloom dynamics is limited. We tracked a recurrent bloom of Chlainomonas sp. on Upper Bagley Lake in the North Cascade Mountains, USA, to assess the spatiotemporal dynamics in bloom color intensity, community photophysiology, and community composition over eight weeks. We found that the algae biomass had a dynamic patchy distribution over space and time, which was decoupled from changes in community composition and life-cycle progress averaged across the bloom. The proportional representation of Chlainomonas sp. remained consistent throughout the study while the overall community composition shows a progression through the bloom. We found that community photophysiology, measured by the maximum quantum yield of PSII (Fv/Fm), decreased on average throughout the bloom. These findings suggest that the Chlainomonas sp. community on Bagley Lake is not simply an algal bloom with rapid increase in biomass followed by a population crash, as is often seen in aquatic systems, though there is a physiological trajectory and sensitivity to environmental stress. These results contribute to our understanding of the biology of Chlainomonas sp. and its response to environmental stress, specifically an extreme warming event.


Subject(s)
Chlorophyceae , Chlorophyta , Lakes , Eutrophication , Seasons
4.
Clin Exp Allergy ; 41(5): 649-56, 2011 May.
Article in English | MEDLINE | ID: mdl-21105919

ABSTRACT

BACKGROUND: It is difficult to find a causal relationship between exposure to Alternaria spores and the development of asthma symptoms in sensitized individuals due to the complexity of clinical situations in which positive diagnostic tests are often found. OBJECTIVE: To analyse the diagnostic efficiency of skin testing (ST) and serum-specific IgE to Alternaria, based on the results of a bronchial specific challenge with Alternaria extracts. METHODS: Seventy-four asthmatic patients sensitized to Alternaria underwent a specific bronchial challenge with this mould. Skin-testing weal sizes, serum-specific IgE values (CAP-system) and bronchial challenge results were analysed by receiver operating characteristics curves (ROC curves) and logistic regression. The sensitivity, specificity, positive and negative predictive values were calculated for different cut-off points. RESULTS: Bronchial challenges to Alternaria elicited a positive result in 45 patients (61%). Skin prick testing almost perfectly predicted the outcome of bronchoprovocation tests (area under the ROC curve of 0.957), whereas intradermal skin testing had moderate efficacy. A negative result for skin prick test (SPT) showed a 4% probability of a positive bronchial challenge in the logistic regression analysis. However, weals around 5.5 mm in diameter had 90% probability of a positive challenge. Quantification of serum-specific IgE correctly classified 86% of the cases. In the logistic regression analysis, a CAP value 16 kU(A)/L predicted a positive bronchial challenge result with 99% accuracy, whereas for a CAP value <0.35 kU(A)/L, this probability was 33%. CONCLUSIONS AND CLINICAL RELEVANCE: Most asthmatic patients with positive SPT results to Alternaria would have a positive bronchial challenge. As atmospheric mould levels may vary significantly with the weather conditions, sensitized patients should be instructed on the risk situations, environmental control measures and the importance of correct medication compliance. Immunotherapy with Alternaria could also be taken into account as a valid therapeutic option.


Subject(s)
Alternaria/immunology , Asthma/immunology , Bronchial Provocation Tests/methods , Immunoglobulin E/immunology , Skin Tests/methods , Adolescent , Asthma/microbiology , Female , Humans , Immunoglobulin E/blood , Male , Predictive Value of Tests , ROC Curve , Regression Analysis , Retrospective Studies , Sensitivity and Specificity , Young Adult
5.
J Hypertens ; 17(12 Pt 2): 1917-23, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10703890

ABSTRACT

OBJECTIVE: To compare the anti-hypertensive effect of combination therapy versus a single drug regimen schedule (dose-titration or switching to a different drug class) in type 2 diabetic hypertensive patients with inadequate blood pressure (BP) control on monotherapy. DESIGN: Prospective, randomized, open-fashion, parallel study of two therapeutic strategies during an 8-week period. SETTING: Primary care centers in Spain. PARTICIPANTS: A total of 898 men and women with type 2 diabetes mellitus and hypertension, receiving antihypertensive treatment with one single drug and whose BP was > 140 and/or 90 mmHg. INTERVENTION: Patients were randomized to a fixed combination therapy (verapamil 180 mg plus trandolapril 2 mg; Knoll AG, Ludwigshafen, Germany) or continued on a single drug regimen, either increasing the dose of the current drug or switching to a different drug class. MAIN OUTCOME MEASURE: Absolute BP reduction in the two groups of treatment, and the percentage of normalized patients (< 140/90 mmHg) in each group. RESULTS: The diastolic BP (DBP) decrease (5.6 mmHg) was significantly greater in patients treated with combination therapy, compared to patients on monotherapy (2.9 mmHg). The decrease in systolic BP (SBP) was not significantly different (11.1 versus 10.0 mmHg). In addition, a significantly higher number of patients treated with combination therapy (82% versus 74%) reached diastolic BP normalization (< 90 mmHg). CONCLUSIONS: In type 2 hypertensive patients with uncontrolled BP despite anti-hypertensive monotherapy, the change to combination therapy was more effective in attaining DBP control than any monotherapy schedule (either increasing the dose or switching to another different drug class).


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Antihypertensive Agents/therapeutic use , Attitude to Health , Calcium Channel Blockers/therapeutic use , Diabetic Angiopathies/drug therapy , Diabetic Angiopathies/psychology , Hypertension/drug therapy , Hypertension/psychology , Indoles/therapeutic use , Verapamil/therapeutic use , Aged , Blood Pressure/drug effects , Diabetes Mellitus, Type 2 , Diabetic Angiopathies/physiopathology , Diastole , Drug Therapy, Combination , Female , Humans , Hypertension/physiopathology , Male , Middle Aged , Prospective Studies
6.
Am J Trop Med Hyg ; 43(4): 386-8, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2240366

ABSTRACT

A case of South American blastomycosis began with an oropharyngeal lesion which was followed by a granulomatous uveitis. The patient was treated with Amphotericin B and showed a clinical regression. Four months later, he developed a right 3rd cranial nerve palsy, aggravating the clinical aspect with a severe generalized involvement of the central nervous system and death. Necropsy showed blastomycotic meningoencephalitis.


Subject(s)
Dermatomycoses/pathology , Eye Infections, Fungal/pathology , Meningoencephalitis/etiology , Oculomotor Nerve Diseases/pathology , Paracoccidioidomycosis/pathology , Adult , Brain/microbiology , Brain/pathology , Cerebellum/microbiology , Cerebellum/pathology , Dermatomycoses/complications , Eye Infections, Fungal/complications , Humans , Male , Oculomotor Nerve Diseases/complications , Oropharynx/microbiology , Oropharynx/pathology , Paracoccidioides/isolation & purification , Paracoccidioidomycosis/complications , Skin/microbiology , Skin/pathology , Uveitis/complications , Uveitis/pathology
7.
Transplant Proc ; 36(9): 2823-5, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15621159

ABSTRACT

BACKGROUND: Cyclosporine-induced nephropathy is a major limitation in heart transplant patients. Cyclosporine dose reduction may lead to substantial early improvement in renal function. Our aim was to study the long-term benefits of therapy with low doses of cyclosporine plus mycophenolate mofetil in heart transplant patients with drug-induced nephrotoxicity. METHODS: Twenty-five adult heart transplant patients with cyclosporine-related nephrotoxicity (mean posttransplant = 41.7 +/- 25.7 months) were included in the retrospective analysis (22 men, mean age = 58.8 +/- 7.9 years.). Patients were switched from azathioprine to mycophenolate mofetil (1 to 3 g/d), followed by a stepwise reduction in cyclosporine dosage (trough cyclosporine level maintained around 100 ng/mL). Renal function was determined by serial measurements of serum creatinine and glomerular filtration rate at 3-month intervals. RESULTS: With a mean follow-up of 30 +/- 13 months, the baseline creatinine of 2.37 +/- 0.5 mg/dL decreased to 1.59 +/- 0.40 mg/dL (P < .0001). The baseline glomerular filtration rate of 36.77 +/- 10.10 mL/min improved to 54.98 +/- 13.80 mL/min (P < .0001). The cyclosporine level was the unique independent variable associated with renal functional improvement (partial R(2) = 0.4). Within the first 3 months, renal function displayed a rapid improvement after conversion to mycophenolate mofetil (P < .001), reaching a plateau, without further significant improvement over the course of time. CONCLUSIONS: Cyclosporine-induced nephrotoxicity is not a progressive, irreversible disease. Reduction in cyclosporine exposure by addition of mycophenolate mofetil is useful to achieve long-term renal functional improvement, thereby avoiding chronic renal failure. A unique, significant factor associated with this improvement was the reduction in cyclosporine level.


Subject(s)
Cyclosporine/adverse effects , Heart Transplantation/immunology , Kidney/pathology , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/therapeutic use , Adult , Creatinine/blood , Follow-Up Studies , Glomerular Filtration Rate , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Kidney/drug effects , Kidney/physiopathology , Retrospective Studies , Time Factors
8.
Clin Exp Allergy ; 37(3): 391-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17359389

ABSTRACT

BACKGROUND: When the clinical history is not conclusive, it may be difficult to make an accurate interpretation of the value of skin tests and serum-specific IgE to cat allergens in asthma cases. OBJECTIVE: To analyse the diagnostic efficiency of skin testing (ST) and serum-specific IgE to cat allergens, based on the results of bronchial-specific challenge with cat epithelium. METHODS: Sixty-four asthma patients (49 with cat exposure and 15 without) who did not clearly relate their asthma symptoms to cat exposure and had a positive skin prick testing and/or a positive cat dander-specific IgE determination (CAP-system) underwent intradermal skin tests and specific bronchial challenge with cat epithelium. The results were analysed by receiver operating characteristics curves (ROC curves) and logistic regression. Sensitivity, specificity, positive predictive values and negative predictive values were calculated for different cut-off points. RESULTS: Twenty-seven patients (42.2%) had a positive bronchial-specific challenge. The area under the ROC curve for serum-specific IgE quantification is 0.85, which makes a good diagnostic tool out of this test. Intradermal ST predicts the outcome of the bronchoprovocation test better than skin prick testing (area under the ROC curve of 0.74 vs. area under the ROC curve of 0.54, respectively). The logistic regression analysis shows that the estimated probability of a positive bronchial challenge is > or =93% if CAP values are > or =17 kU(A)/L, whereas if CAP values are less than 0.35 kU(A)/L the estimated probability of a positive bronchial challenge is 16%. When the intradermal skin test is negative, the estimated probability of a positive bronchoprovocation test is 9%, being the test that better identifies patients with a negative bronchoprovocation test. CONCLUSIONS: Levels of serum-specific IgE to cat allergens and intradermal ST can be used to diagnose and treat more accurately asthmatic patients sensitized to cat epithelium when there is uncertainty about cat epithelium causality.


Subject(s)
Allergens/analysis , Cats , Hypersensitivity/immunology , Immunoglobulin E/analysis , Respiratory Hypersensitivity/immunology , Adolescent , Adult , Allergens/immunology , Animals , Bronchial Provocation Tests/methods , Female , Humans , Hypersensitivity/diagnosis , Male , Middle Aged , Respiratory Hypersensitivity/diagnosis , Skin Tests/methods
9.
Histopathology ; 46(2): 184-94, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15693891

ABSTRACT

AIMS: To investigate the p53 pathway in meningeal haemangiopericytomas (MHPCs), p14/ARF, p53 protein expression and two wild-type (wt) p53-induced proteins (HDM2 and p21/WAF1) were studied in 18 MHPCs, 11 primary, four of them recurrent on one, one, two and four occasions. METHODS: Immunohistochemical detection of p14/ARF, p53, p21/WAF1, HDM2 and Ki67 proliferative index (PI) protein expression. RESULTS: Ki67 index was > 5% in eight out 18 cases (44.4%). The PI in recurrent cases increased with neoplastic progression. Simultaneous p53 and wt p53 transactivated gene (p21/WAF, HDM2) expression occurred in all cases. This argues against p53 mutation. HDM2 overexpression was observed in 10 cases (55.5%). Double-immunofluorescence staining and laser scanning confocal microscopy (LSCM) displayed HDM2 and p53 colocalization. This strongly suggests that HDM2 binds and inactivates p53 that could be pathogenic for MHPCs, by a different mechanism than point mutation. p14/ARF expression > 5% was observed in 12 cases (66.6%). A normal (diffuse) pattern of expression was seen in 13 cases (72.2%). Focal loss of expression was observed in five patients (27.7%): three primary cases and two recurrences. Therefore, p14/ARF down-regulation may also contribute to the development of MHPC. CONCLUSION: HDM2 overexpression, sometimes combined with focal loss of p14/ARF expression, may play a pathogenic role in MHPCs.


Subject(s)
Hemangiopericytoma/pathology , Meningeal Neoplasms/pathology , Neoplasm Proteins/biosynthesis , Cell Cycle Proteins/analysis , Cyclin-Dependent Kinase Inhibitor p21 , Fluorescent Antibody Technique/methods , Hemangiopericytoma/metabolism , Humans , Immunohistochemistry , Ki-67 Antigen/analysis , Meningeal Neoplasms/metabolism , Microscopy, Confocal , Nuclear Proteins/biosynthesis , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins c-mdm2 , Tumor Suppressor Protein p14ARF/biosynthesis , Tumor Suppressor Protein p53/biosynthesis
10.
Acta Neurochir (Wien) ; 147(1): 5-16; discussion 16, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15565480

ABSTRACT

BACKGROUND: Most scales used to assess prognosis after subarachnoid haemorrhage (SAH) are based on the level of consciousness of the patient. Based on information from a logistic regression model, Ogilvy et al. developed a new grading scheme (Massachussetts General Hospital (MGH) Scale) which applied a simple scoring method to each prognostic factor considered relevant such as level of consciousness, age, quantity of blood in the first CT scan and size of the aneurysm. The purpose of this study is to introduce a modified version of the MGH scale, built up using factors applicable to every patient suffering SAH, and compare this new scale to the World Federation of Neurological Surgeons scale (WFNS), the Glasgow Coma Scale (GCS) scale for SAH and the MGH scale. METHOD: A series of 442 patients consecutively admitted to Hospital 12 de Octubre between January 1990 and September 2001 with the diagnosis of spontaneous SAH were retrospectively reviewed. Outcome was assessed by means of the Glasgow Outcome Scale measured six months after hospital discharge. Differences between grades of the WFNS, the GCS scale for SAH, the MGH scale and the new scale were computed by chi2 statistics. ROC curves were plotted for the different scales and their areas compared. FINDINGS: Both WFNS and GCS scales fail to present significant differences between most of their grades, while the proposed scale shows a constant inter-grade significant difference in predicting outcome. The proposed scale presents a significantly higher prognostic efficacy in the whole series of patients suffering spontaneous SAH, patients with idiopathic subarachnoid haemorrhage (ISAH) and patients with confirmed aneurysmal SAH. The MGH scale is not applicable to some groups of patients suffering SAH. INTERPRETATION: Grading scales including additional factors to the level of consciousness show higher prognostic efficacy. The proposed modification of the MGH scale makes it applicable to every patient suffering SAH without losing its prediction capability.


Subject(s)
Glasgow Coma Scale , Severity of Illness Index , Subarachnoid Hemorrhage/diagnosis , Adult , Aged , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prognosis , ROC Curve , Reproducibility of Results , Retrospective Studies , Subarachnoid Hemorrhage/therapy
11.
Scand J Gastroenterol ; 32(1): 70-6, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9018770

ABSTRACT

BACKGROUND: We wanted to investigate the influence of viral genotype on the severity of liver injury and response to interferon and whether the level of viremia differs in accordance with genotype, severity of liver disease, and response to interferon in patients with hepatitis C virus (HCV) infection. METHODS: We studied 118 patients with HCV-related liver disease. HCV genotypes were determined with a line probe assay, and serum HCV RNA levels with a competitive reverse transcription polymerase chain reaction assay. RESULTS: HCV type 1b was the most prevalent genotype (88%). It was present in 100% of cirrhotic patients, with or without hepatocellular carcinoma (HCC), but only in 78% of patients with chronic hepatitis (P < 0.001). The response to interferon was better in patients infected with non-1b HCV genotypes (P = 0.002). In a multivariate analysis non-1b HCV genotypes and a low hepatic fibrosis correlated with a favorable response to interferon. Among patients with chronic hepatitis those infected with HCV type 1b were older (P < 0.001), and age was the only independent factor associated with HCV type 1b. Viremia levels differed neither between genotypes nor in response to interferon and was significantly lower in patients with cirrhosis and HCC. CONCLUSIONS: HCV 1b was associated with more severe liver disease and a worse response to interferon therapy. Non-1b genotypes and a lower liver fibrosis were the only independent predictors of a favorable response to interferon. Levels of HCV viremia differed neither among different genotypes nor in response to interferon and decreased with advanced liver disease.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/genetics , Hepatitis C/drug therapy , Hepatitis C/virology , Interferon-alpha/therapeutic use , Viremia/drug therapy , Viremia/genetics , Aged , Female , Genotype , Hepacivirus/physiology , Hepatitis C/pathology , Humans , Male , Middle Aged , Multivariate Analysis , Prospective Studies , RNA, Viral/blood , Viremia/pathology , Virus Replication
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