Evaluación de la formación de biopelículas en aislamientos bacterianos y fúngicos por el método semicuantitativo de microtitulación con cristal violeta y el cualitativo de agar con rojo Congo / Assessment of biofilms formation of bacterial and fungal isolates using qualitative Congo red agar and semiquantitative crystal violet microtiter methods

Introducción. El 65 % de las infecciones humanas son producidas por bacterias o levaduras, cuya capacidad de formar biopelículas las hace más resistentes a los antimicrobianos y antifúngicos. Objetivo. Determinar la capacidad de formación de biopelículas en aislamientos bacterianos y fúngicos por medio de los métodos cuantitativo de microtitulación con cristal violeta y cualitativo de cultivo en agar con rojo Congo. Materiales y métodos. Con el método cuantitativo, se utilizaron los medios de cultivo infusión cerebro-corazón, tripticasa de soya y Müeller-Hinton para aislamientos bacterianos; para levaduras, se usaron caldo infusión cerebro-corazón y Sabouraud dextrosa. Para el método cualitativo de cultivo en agar, se utilizaron los mismos medios de cultivo más una solución con 3 % de rojo Congo y 10 % de dextrosa. Cómo método de referencia, se utilizó la propuesta de Stepanovic et al. Resultados. Se evaluaron 103 aislamientos bacterianos y 108 de levaduras. No es recomendable sustituir el caldo infusión cerebro-corazón por los caldos tripticasa de soya y Müeller-Hinton en el método cuantitativo, para evaluar la formación de biopelículas en los aislamientos bacterianos. El medio Sabouraud dextrosa, en caldo y agar, puede sustituir al de infusión de cerebro-corazón para evaluar la formación de biopelículas en levaduras, tanto por el método cuantitativo como por el cualitativo. Conclusión. El estudio de las biopelículas en el laboratorio de microbiología, a partir del método cualitativo de cultivo en agar con rojo Congo, es un procedimiento sencillo, rápido y de bajo costo, que proporciona información útil para el diagnóstico y la terapéutica de infecciones persistentes causadas por bacterias y levaduras.

Introduction. Sixty-five percent of human infections are caused by bacteria or yeasts able to form biofilms. This feature makes them more resistant to antimicrobials and antifungals. Objective. To determine biofilm formation capacity of bacterial and fungal isolates by quantitative crystal violet microtiter and qualitative Congo red agar methods. Materials and methods. Brain-heart infusion, trypticase soy broth and Müeller-Hinton culture media were used in bacterial isolates for the quantitative method; brain-heart infusion broth and Sabouraud dextrose were used for yeasts. The same culture media plus 3% Congo red and 10% dextrose were used to apply the qualitative method in agar. The proposal by Stepanovic, et al. was used as a reference method. Results. We evaluated 103 bacterial isolates and 108 yeasts isolates. We did not recommend substitute brain-heart infusion broth for trypticase soy and Müeller-Hinton broths for biofilm formation assessment in bacterial isolates using the quantitative method. Sabouraud dextrose medium, both broth and agar, can replace brain-heart infusion to assess biofilm formation in yeasts, quantitatively and qualitatively. Conclusion. The study of biofilms in the microbiology laboratory, using Congo red agar qualitative method, is a simple, fast, and inexpensive procedure that provides precise information for the diagnosis and treatment of persistent infections caused by bacteria and yeasts.

Masked ocular amyloidosis simulating xanthelasma and follicular conjunctivitis: case reports / Amiloidose ocular mascarada simulando xantelasma e conjuntivite folicular: relatos de casos

ABSTRACT Amyloidosis is a rare disease in which ocular involvement may occur as an isolated event or associated with a systemic disease. This paper describes two clinical cases of ophthalmologic manifestations of amyloidosis: a bilateral eyelid lesion similar to xanthelasma and tarsal conjunctival disease similar to follicular conjunctivitis. The anatomopathological analysis confirmed the diagnosis.

RESUMO A amiloidose é uma doença rara que pode ter o acometimento ocular como forma isolada ou estar associada a doenças sistêmicas. Neste relato, são descritos dois casos clínicos de alterações oftalmológicas da amiloidose: um que se manifestou por meio de lesão palpebral bilateral de aspecto similar ao xantelasma. O outro era uma afecção em conjuntiva tarsal, semelhante à conjuntivite folicular. O estudo anatomopatológico confirmou o diagnóstico.

A Study on the Role of Urinary Congophilia in Early Detection of Preeclampsia

Introduction?Preeclampsia and eclampsia are important causes of maternal morbidity. Preeclapmtic women secrete misfolded proteins in the urine. Buhimschi et al had developed a new test for diagnosis of preeclampsia. This test is based on staining of misfolded protein with Congo red dye. Misfolded proteins are derived from syncytiotrophoblast microparticles (STBMs). These STBM are membrane bound vesicles and contain misfolded proteins. In preeclampsia, glomeruli of kidneys are disrupted and these damaged protein reach the urine. Aim and Objective?This study aimed to investigate the role of urinary congophilia in early prediction of preeclampsia. Materials and Methods?This test was done in 250 pregnant women attending the Gynaecological Outpatient Department. Urine sample of early morning was taken and test was done in the Department of Biochemistry. The included pregnant women were of gestational age between 14 and 18 weeks. The staining of urine with Congo red dye was done and washed with methanol. The retention of dye was interpreted with naked eye. The more retention of dye, the more chances of developing preeclampsia later. The patients were followed-up till delivery. The patents who developed preeclampsia later part of pregnancy were recorded. Mean arterial pressure (MAP) and past history and body mass index were also recorded. Results?Out of 250 patients, 30 developed preeclampsia later. A total of 34 patients were having positive urinary congophilia and only 20 patients developed preeclampsia later. MAP more than 90?mm Hg is abnormal but 66.7% of patients who developed preeclampsia had MAP >90?mm Hg. In 16.7% of patients, who developed preeclampsia later, had positive past history of hypertension. In 66.7% of patients, who were positive for urinary congophilia, later developed preeclampsia. Conclusion?Preeclampsia and eclampsia are important causes of maternal mortality and morbidity. So, early detection can prevent complications and timely management. Urinary congophilia is one of such test which can help in early prediction of preeclampsia. If it is combined with past maternal history and MAP, it gives more good results. The detection rate is much higher if signs and symptoms of preeclampsia are noticed timely.

Formación de biopelículas por Candida parapsilosis sensu stricto y su perfil de susceptibilidad en Venezuela / Biofilm-forming of Candida parapsilosis sensu stricto and its susceptibility profile in Venezuela

Una de las principales consecuencias del desarrollo de biopelículas es la resistencia a los antifúngicos. Se determinó la formación de biopelículas por Candida parapsilosis sensu stricto aisladas de sangre y su perfil de susceptibilidad. Se evaluaron 30 cepas de C. parapsilosis sensu stricto de la Red de Candidemias del Dpto. de Micología del Instituto Nacional de Higiene Rafael Rangel-Venezuela, por el método cuantitativo en microplaca con tinción de cristal violeta y el método cualitativo en agar Sabouraud dextrosa suplementado con rojo Congo. Se utilizó el método de microdilución según el documento M-27 del Clinical and Laboratory Standards Institute. La formación de biopelículas de C. parapsilosis sensu stricto por el método cuantitativo fue de 63% y por el método cualitativo de 50%. El método cualitativo presentó valores de sensibilidad, especificidad, valores predictivos positivo y negativo de 61,1%, 23%, 78,6%, 43,8% respectivamente frente al método cuantitativo. Los aislados en forma planctónica fueron 100% sensibles a anfotericina B y caspofungina, con susceptibilidad variable a los azoles. El método cuantitativo es una técnica confiable para determinar la formación de biopelículas. El método cualitativo puede usarse como método pantalla inicial. No se encontró relación entre la susceptibilidad de las formas planctónicas y la capacidad de producción de biopelículas

One of the main consequences of biofilm development is resistance to antifungals. Biofilmforming by Candida parapsilosis sensu stricto isolated from blood and its susceptibility profile was determined. Thirty strains of C. parapsilosis sensu stricto belonging to the Candidemia Network of the Mycology Department of the Instituto Nacional de Higiene Rafael Rangel-Venezuela, were evaluated by microplate quantitative method with violet crystal staining, and Sabouraud dextrose agar supplemented with Congo red qualitative method. The microdilution method was used to determine the susceptibility, according to the Clinical and Laboratory Standards Institute M-27 document. Biofilm formation of C. parapsilosis sensu stricto by both quantitative and qualitative method was 63% and 50%, respectively. Sensitivity, specificity, and positive and negative predictive values of the qualitative method were 61.1%, 23%, 78.6%, and 43.8% respectively, when compared with quantitative method. Planktonic isolates were 100% sensitive to amphotericin B and caspofungin, with variable susceptibility to azoles. Quantitative method is a reliable assay to determine biofilm formation, while qualitative method can be used as an initial screening assay. No relationship was found between susceptibility of planktonic isolates and the ability to biofilm-forming

Study of biofilm formation in bacterial isolates from contact lens wearers

Purpose: To detect biofilm forming capacity of bacterial isolates obtained from the conjunctiva, contact lens and accessories of contact lens wearers using phenotypic and genotypic methods. Methods: Bacterial strains were collected from the conjunctiva, contact lens and lens storage cases of contact lens wearers. The phenotypic detection of biofilm production was done using the tube method and congo red agar method. The biofilm-forming related genes, icaA, of Coagulase negative Staphylococcus (CONS) and Staphylococcus aureus, and pslA, of P. aeruginosa, were detected using PCR. Results: A total of 265 bacterial isolates which included S. aureus, CONS, Pseudomonas, Nil-fermenter Gram-negative bacilli (NFGNB), Bacillus spp, Diphtheroids, Micrococci, Klebsiella pneumonia, Klebsiella oxytoca, E. coli, Proteus mirabilis, Proteus vulgaris, Citrobacter koseri, Citrobacter freundii, Enterobacter cloacae, Moraxella were obtained. Of the 265 isolates, 53.5% were moderately positive, 33.2% strongly positive and 13.2% negative for biofilm production by tube method and 36.6% were moderately positive, 40% strongly positive and 23.3% negative for biofilm production by congo red agar method. Of the four S. aureus isolates, two (50%) showed the presence of icaA gene. Of the 23 CONS isolates, three (13%) showed the presence of icaA gene. All the Pseudomonas isolates were negative for presence pslA (1119 bp) gene though most of them were phenotypically positive for biofilm formation. Conclusion: Most of the bacterial isolates obtained from contact lens wearers had the potential to produce biofilms. Tube method and Congo red agar method exhibited significant statistical correlation (P-value = 0.006) and picked up a good number of biofilm-forming isolates, hence may be used for detection of biofilm production. The absence of biofilm-forming gene did not rule out the possibility for phenotypic biofilm production by bacteria.

Primary localized amyloidosis in nasopharynx: A Case Report

@#Nasopharyngeal amyloidosis is an extremely rare benign tumour. It is divided into localized or systemic amyloidosis. It is more common in men. Clinical presentation includes nasal blockage, epistaxis and reduced hearing. Classical positive Congo red stain and appearance of apple green birefringence on polarized microscopy confirms the diagnosis of amyloidosis. We present a case of nasopharyngeal amyloidosis in a 44-year old lady who presented with acute hearing loss for 1 week with epistaxis mimicking nasopharyngeal carcinoma. Clinical examination showed a nasopharyngeal mass with biopsy proven AA amyloidosis. She is now cured of amyloidosis following endoscopic transnasal excision of tumour. We discuss on the similarity of presentation between nasopharyngeal carcinoma; the commonest malignant tumour in our region and the much rarer nasopharyngeal amyloidosis as well as highlighting the importance in early recognition of the latter in view of its known risk of systemic involvement.

Papel del médico de familia en el diagnóstico concomitante de mieloma y amiloidosis primaria en una misma paciente: caso clínico / Multiple myeloma associated with a secondary amyloidosis: report of one case

Multiple Myeloma is a myeloproliferative disorder of plasma cells, which may be complicated with secondary amyloidosis. We report a 48 year old woman consulting to primary care for weight loss and malaise. An initial laboratory study revealed a hypogammaglobulinemia with a monoclonal component and lambda light chains. These results motivated her derivation to hematology: her serum calcium was 11.8 mg/dl, immunofluorescence showed a monoclonal component of lambda chains and urine Bence-Jones protein was positive. A bone marrow biopsy confirmed plasma cell infiltration. A Congo-red stain of a rectal biopsy was positive. The patient was treated with thalidomide, bortezomid and dexamethasone.

Pindborg tumor: Pathology with special stains

Odontogenic tumors constitute a wide spectrum of lesions ranging from malignant and benign neoplasms to dental hamartomas, all derived from the epithelial and ectomesenchymal remnants of the tooth forming apparatus. Calcifying epithelial odontogenic tumor (CEOT) is an uncommon, benign epithelial odontogenic tumor first described by Pindborg in 1956. It is a universally accepted eponym for this neoplasm. Pindborg tumor or CEOT is a locally aggressive neoplasm that accounts for 1% of the total odontogenic tumors, with recurrence in 14% of cases. The etiology of this tumor remains an enigma to the clinician. Pindborg suggested that the tumor arises from the remnants of reduced enamel epithelium of an unerupted tooth. Recent studies in literature report that the tumor arises from stratum intermedium. We report a case of Pindborg tumor in a 22-year-old male patient in the left mandibular posterior region. Radiographically, a well-defined radiolucency was associated with unerupted mandibular second molar which was displaced to the inferior border of the mandible. Along with routine haematoxylin and eosin stains, this case reports histopathological findings using Congo red stain and modified Gallegos stain.

Atrophic nodular cutaneous amyloidosis*

Abstract: Primary cutaneous amyloidosis is limited to the skin without involving any other tissue. Nodular amyloidosis is rare, and atrophic nodular cutaneous amyloidosis is even rarer. We describe the fourth case of atrophic nodular cutaneous amyloidosis by searching PubMed databases. A 52-year-old female presented to our hospital with a 2-year history of orange papules and nodules without subjective symptom on her right abdomen. Review of systems was negative. Atrophic nodular amyloidosis may progress to primary systemic disease in up to 7% of cases. Because our patient had no systemic involvement, she was diagnosed with atrophic nodular cutaneous amyloidosis based on characteristic symptoms and histopathologic examination. Routine follow-up for this patient is necessary to detect any potential disease progression.

Azo Dye Mineralization by Phanerochaete Chysosporium in a Sequencing Bath Reactor

ABSTRACT The mineralization of the azo dye congo red by the fungi Phanerochaete chrysosporium was studied in two sequential batch bioreactors (R1 and R2), operated in cycles of 48 h (step I) and 24 h (step II). In step I, glucose concentration was 1 g.L-1 in both reactors and in step II, 1 g.L-1 of glucose was maintained in R1, but R2 received no addition of glucose. In step I, the average dye removal efficiencies were 76 ± 29 % (R1) and 53 ± 15% (R2), while in step II the averages recorded for dye removal for R1 and R2 were 84 ± 15 and 70 ± 28%, respectively. The rates of dye removal were 0.04 h-1 in R1 and 0.03 h-1 in R2 in step I. Higher rates were obtained in step II, 0,07 h-1 and 0,02 h-1 for R1 and R2, respectively. The highest dye removal occurred in R1 and, in R2, the residual dye was further removed. Laccase was the oxidised at higher amount, in step I was 54 μmol.min-1 for R1 and 38 μmolmin-1 for R2. The proposed treatment system was very effective in removing the azo dye, however the mineralization may not be complete and some by-products may have been formed, according to spectrofotometric analysis, were the peak corresponding to benzene, 220 nm, persisted.

Evaluation of Biofilm Formation and Presence of Ica Genes in Staphylococcus epidermidis Clinical Isolates

OBJECTIVES: Biofilm formation is one of the important features of Staphylococcus epidermidis, particularly in nosocomial infections. We aimed to investigate the biofilm production by phenotypic methods and the presence of ica genes in S epidermidis. METHODS: A total of 41 S epidermidis isolates were recovered from different clinical specimens. Biofilm formation was evaluated by microtiter plate, tube method and Congo red agar method. The presence of icaA and icaD genes was investigated by PCR. Validity of methods (sensitivity and specificity), and metrics for test performance (positive/negative predictive value, and positive/negative likelihood ratio) were determined. RESULTS: By both microtiter plate and tube method, 53.6% of S epidermidis isolates were able to produce biofilm, whilst only 24.4% of isolates provided a biofilm phenotype on Congo red agar plates. icaA and icaD genes were found in 100% and 95.1% of isolates, respectively. Biofilm phenotypes accounted for 4.8% by microtiter plate assay, despite the absence of the ica gene. Congo red agar and PCR exhibited a lower sensitivity (18% and 45.5%, respectively) for identifying the biofilm phenotype in comparison to microtiter plate. CONCLUSION: The microtiter plate method remains generally a better tool to screen biofilm production in S epidermidis. In addition, the ability of S epidermidis to form biofilm is not always dependent on the presence of ica genes, highlighting the importance of ica-independent mechanisms of biofilm formation. The use of reliable methods to specifically detect biofilms can be helpful to treat the patients affected by such problematic bacteria.

Diagnóstico clínico e dermatoscópico de um caso de amiloidose maculosa exuberante / Clinical and dermoscopic diagnosis of a case of exuberant macular amyloidosis

A amiloidose é entidade caracterizada pela deposição de uma proteína modificada. Pode acometer a pele depositando-se na derme papilar. Em geral cursa com máculas acastanhadas predominantes na região interescapular e raramente com formas generalizadas. O presente relato refere-se a paciente do sexo feminino com queixa de manchas hipercrômicas de aumento progressivo para todo o corpo. A dermatoscopia se mostrou extremamente eficaz para a localização dos diversos focos de incontinência pigmentar, que junto com os queratinócitos apoptótico constituem a base fisiopatológica para a formação da proteína amiloide.

Amyloidosis is characterized by the deposition of a modified protein. It can affect the skin by accumulating in the papillary dermis. In general, it develops with brownish maculae predominant in the interscapular region, and rarely coursing with generalized forms. This report describes a 59 year-old female patient who had had a spot in the lower back for 43 years, which in the last 8 years had progressively spread for the entire body. Dermoscopy has proven extremely effective in locating the various foci of pigmentary incontinence, which together with apoptotic keratinocytes constitute the pathophysiological basis for the formation of the amyloid protein.

Antioxidant activity and protective role on protein glycation of synthetic aminocoumarins

Background: Synthesized aminocoumarins are heterocyclic compounds possessing potential for the treatment of insulin-dependent diabetes mellitus with unexplored anti-glycative action. Results: In this study 4-aminocoumarin derivatives (4-ACDs) were evaluated in vitro for antiglycation (AG) activities by using the human serum albumin (HSA)/glucose system, for 8 weeks of incubation. The glycation and conformational alteration of HSA in the presence of the tested compounds were evaluated by Congo red assay, fluorescence and circular dichroism spectroscopy. The antioxidant (AO) capacity were also tested by four different assays including: DPPH (2,2'-diphenyl-1-picrylhydrazyl radical), ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulphonate) diammonium salt), FRAP (ferric reducing antioxidant power) and β-carotene-linoleic acid assay. The tested compounds showed AG and AO effects. The intensity of the accomplished AO potential is related to the type of the used assay. Significant alterations in the secondary (monitored by CD spectropolarimetry) and tertiary structure (assessed by spectrofluorimetry) of HSA upon glycation were mitigated by the 4-ACDs, suggesting their suppressive role in the late stage (post-Amadori) of the HSA glycation. Conclusions: By the analogues, in vitro ascertained AO and AG properties of 4-ACD may be recognized as rationale for their protective role against oxidative changes of proteins, thereby precluding diabetic complications in humans.

Tumor Associated Tissue Eosinophilia in Oral Squamous Cell Carcinoma: A Histo-Chemical Analysis

Background: Tumor associated tissue eosinophilia (TATE) is believed to play a significant role in biological behavior of the carcinoma. Eosinophils are involved in immune reaction. Various studies have been carried out regarding their role in tumor progression or regulation. In oral squamous cell carcinoma (OSCC), eosinophils are associated with favourable or unfavourable prognosis and hence their role is yet unclear. To compare the tissue eosinophils in OSCC and normal tissue and to correlate the expression of TATE in different grades of OSCC. Method: Study comprised 30 cases, 6 normal and 24 histopathologically diagnosed with OSCC. 4 micron thick sections were stained using 1% congo red solution. The sections were examined under high power (×40) and 10 consecutive microscopic fields were studied. The average number of eosinophils were statistically analysed. Results: The tabulated results showed that the median value of tissue eosinophils, increased in OSCC compared to normal mucosa. Analysis on different grades of carcinoma showed a higher TATE in Well differentiated squamous cell carcinoma as compared to other grades. Conclusion: The higher eosinophil count in OSCC compare to normal tissue might have a role in stromal invasion and infiltration. TATE can be used as an indicator of favourable prognosis in OSCC.

Role of wild birds as carriers of multi-drug resistant Escherichia coli and Escherichia vulneris

Emergence and distribution of multi-drug resistant (MDR) bacteria in environments pose a risk to human and animal health. A total of 82 isolates of Escherichia spp. were recovered from cloacal swabs of migrating and non-migrating wild birds. All bacterial isolates were identified and characterized morphologically and biochemically. 72% and 50% of isolates recovered from non-migrating and migrating birds, respectively, showed positive congo red dye binding (a virulence factor). Also, hemolysin production (a virulence factor) was showed in 8% of isolates recovered from non-migrating birds and 75% of isolates recovered from migrating birds. All isolates recovered from non-migrating birds were found resistant to Oxacillin while all isolates recovered from migrating birds demonstrated resistance to Oxacillin, Chloramphenicol, Oxytetracycline and Lincomycin. Some bacterial isolates recovered from non-migrating birds and migrating birds exhibited MDR phenotype. The MDR isolates were further characterized by API 20E and 16S rRNA as E. coli and E. vulneris. MDR Escherichia isolates contain ~1-5 plasmids of high-molecular weights. Accordingly, wild birds could create a potential threat to human and animal health by transmitting MDR bacteria to water streams and other environmental sources through their faecal residues, and to remote regions by migration.

Prevalence of adhesive genes among uropathogenic Escherichia coli strains isolated from patients with urinary tract infection in Mangalore.

The study was carried out to detect the adhesive genes pap (pyelonephritis associated pili), sfa (S fimbrial adhesin) and afa (afimbrial adhesin) from Escherichia coli strains isolated in patients diagnosed with urinary tract infection (UTI). A total of 23% of the isolates were positive for pap, sfa and afa genes with a prevalence of 60.87% (14/23), 39.1% (9/23) and 39.1% (9/23), respectively. Prevalence of multiple adhesive genes was 8.7% (2/23) for pap and afa, 30.43% (7/23) for pap and sfa. Significant numbers of isolates were positive for Congo red binding (80%) and haemolysin production 60%. The prevalence of multiple adhesive genes indicate the potential to adhere and subsequently cause a systemic infection among UTI patients.

Amyloid nephropathy:a clinicopathologic analysis of 31 cases / 临床与实验病理学杂志

Purpose To investigate the clinical and pathological features of amyloid nephropathy. Methods A retrospective analysis was conducted in 31 cases of amyloidosis nephropathy. The clinical data and pathologic features of kidney biopsy were analyzed. Re-sults 31 cases of amyloid degeneration accounted for 1. 19% (31/2 603) in all patients of kidney biopsy in the same period. 15 pa-tients were female, and 16 males. Patients’ age ranged from 36 to 77 years old, with mean age of (61. 28 ± 10. 95) years. Clinical staging showed that simple proteinuria were 4 cases (12. 90%), nephrotic syndrome, 21 cases (67. 74%), and renal failure, 6 cases (19. 35%). Under microscope, amyloid deposits were observed in the glomerular mesangial area, capillary basement membrane and small arteries, and those also deposited between renal interstitial and tubular basement membrane in severe cases. Potassium permanga-nate oxidation Congo red staining showed that AL type were 27 cases and AA 4 cases. Immunofluorescence study in some cases showed some degree of weak immunoglobulin and complement deposition, but some cases were negative. Immunohistochemical staining showed different expression of immunoglobulin light chain κ and λ light chains. Under electron microscope, amyloid fibrils were noted in the mesangial area and capillary walls. Conclusion Amyloidosis nephropathy occurs in middle-aged patients with kidney disease, some-times lack of specific clinical manifestations. Renal biopsy is the only approach to confirm the diagnosis. For suspicious patients, renal biopsy should be done as early as possible.

Azo dye degradation by Phanerochaete chrysosporium in the medium enriched with nitrogen in the presence of primary co-substrate

This work sought to evaluate the ability of fungi Phanerochaete chryosporium to degrade congo red azo dye in batch reactor, evaluate the influence of glucose and wheat bran as co-substrates on the removal of the dye in the medium and investigate the influence of ammonium chloride, ammonium nitrate and ammonium sulfate as the inorganic nitrogen source for the process. Wheat bran was not effective satisfactorily for the removal of dye and organic matter had no desired effect for the removal of color and organic matter and showed the lowest values of k2, 0.008 M-1.d-1and 0.0004 M-1.d-1, respectively. Glucose presented the best response with the highest final percentage of dye removal (97%) and rate of dye removal (0.017 M-1.d-1), without adding an external source of nitrogen.

Optimization of phenoxazinone synthase production by response surface methodology and its application in Congo red decolourization

Background: Enzymatic decolourization has been recently proposed as a promising and eco-friendly method for treatment of synthetic dye-contaminated wastewaters. However, the processes require large quantities of enzymes, attracting significant attention in developing efficient methods for mass production of multifunctional enzymes. Several methods such as response surface methodology (RSM) and orthogonal experiment have been applied to optimize the parameters in bioprocesses for enzyme production. Results: In the present study, a laccase-like enzyme, phenoxazinone synthase (PHS) originated from Streptomyces antibioticus was recombinantly expressed in Escherichia coli BL21 (DE3). The production of PHS in E. coli BL21 was optimized by response surface methodology based on Box-Behnken design. A full third-order polynomial model was generated by data analysis with Statistica 8.0 in which the optimal conditions for PHS production were calculated to be 1.525 mM CuSO4 and 16.096 hrs induction at temperature of 29.88ºC. The highest PHS production under optimal conditions was calculated to be 4098.51 U/l using the established model. Average PHS production obtained from actual production processes carried out under the calculated optimal conditions was 4052.00 U/l, very close to the value predicted by the model. Crude PHS was subsequently tested in Congo red decolourization which exhibited a low decolourization rate of 27% without mediator. Several mediators were found to improve PHS-catalyzed Congo red decolourization, with the highest rate of 73.89% obtained with 2,2’-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) as mediator under optimized conditions of 4000 U/l PHS activity, 10 μM ABTS, 100 μM Congo red, and 8 hrs reaction time. Conclusion: Our results indicated that PHS recombinantly produced in E. coli BL21 was a prospective enzyme for decolorizing reactive dye Congo red.

A Case of Systemic Amyloidosis Found by Goiter in Crohn's Disease

Secondary amyloidosis is characterized by accumulation of insoluble, fibrous amyloid proteins in various tissues and organs, accompanied by infectious or inflammatory diseases. Amyloidosis may involve the thyroid, gastrointestinal tract, kidneys, liver, or bone marrow. Amyloidosis as a complication of Crohn's disease is rare but serious, and may worsen the prognosis. We have experienced a case of amyloid goiter and gastrointestinal amyloidosis secondary to Crohn's disease. A 74-year-old female patient with Crohn's disease was admitted to Soonchunhyang University Hospital with general weakness and poor oral intake. Anterior-neck diffuse goiter and tenderness around the navel were found. Amyloid goiter and gastrointestinal amyloidosis diagnosed by sonoguided needle biopsy of the thyroid and endoscopic biopsies of the stomach and duodenum.