Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogeni... more Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogenic potentials are a matter of debate since their discovery. This study aims to investigate the relationship between the activation of ulcerative colitis (UC) and irritable bowel syndrome (IBS) with these protists. A total of 100 patients (35 IBS, 35 active UC, and 30 remittent UC), diagnosed at Hacettepe University Adult Hospital (Ankara, Turkey), were screened for D. fragilis and Blastocystis sp. with microscopic examination using the methods of wet mount, trichrome staining, conventional PCR, nested PCR, real-time PCR and genotyping. Eight patients (4 IBS, 2 active, and 2 remittent UC patients) were found to be D. fragilis positive. 18S rRNA region of the parasite was amplified in four of the patients, whereas cathepsin L-like cysteine peptidase, clan Sc, family S9, serine peptidase, and clan MH, family M20 metallopeptidase in six different patients. All isolates were Genotype 1 by sequencing. Sequence results showed very limited diversity. A total of nine patients (3 IBS, 5 active UC, 1 remittent UC) were found to be positive for Blastocystis sp., all of which were Subtype 3. One active UC and one IBS patient were found to be positive for both parasites. No statistically significant difference was detected between the patient groups for parasite detection. D. fragilis was found to be related to older age (p=0,045). In our study, no significant correlation was identified between D. fragilis and Blastocystis sp., and the activation of UC and IBS. More studies are needed on the host-parasite relationship, including the role of gut microbiota, together with transcriptomic and metabolomic assessments to unveil the pathogenicity of both protists.
E. Bellikci-Koyu, B.P. Sarer-Yurekli, Y. Akyon, A.G. Ozgen, A. Brinkmann, A. Nitsche, K. Ergunay,... more E. Bellikci-Koyu, B.P. Sarer-Yurekli, Y. Akyon, A.G. Ozgen, A. Brinkmann, A. Nitsche, K. Ergunay, E. Yilmaz, M. P. St-Onge and Z. Buyuktuncer Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, Turkey, Department of Nutrition and Dietetics, Faculty of Health Sciences, Izmir Katip Celebi University, Turkey, Department of Endocrinology, Faculty of Medicine, Ege University, Turkey, Department of Medical Microbiology, Faculty of Medicine, Hacettepe University, Turkey, Robert Koch Institute, Center for Biological Threats and Special Pathogens 1 (ZBS-1), Germany, Department of Medical Biology, Faculty of Medicine, Hacettepe University, Turkey (Retired Professor) and Sleep Center of Excellence & Division of General Medicine, Department of Medicine, Columbia University Irving Medical Center, New York, USA
The Journal of Clinical Endocrinology & Metabolism, 2020
Context Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder. Emerging ani... more Context Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder. Emerging animal and human data point to various changes in microbiota that could be linked with the syndrome. However, the effects of therapeutic approaches on gut microbial composition in women with PCOS remain unknown. Objective We aimed to assess whether gut microbial composition is altered in PCOS and to determine the potential impact of oral contraceptive (OC) use on gut microbiota. Design Prospective observational study. Setting Tertiary referral hospital. Patients and Other Participants The study included 17 overweight/obese patients with PCOS and 15 age- and body mass index-matched healthy control women. Main Outcome Measures At baseline, clinical, hormonal, and metabolic evaluations and gut microbial composition assessment by 16S rRNA gene amplicon sequencing were performed for both groups. All measurements were repeated in patients after receiving an OC along with general lifestyle advice ...
Cystic echinococcosis (CE) is one of the most common zoonotic diseases worldwide, particularly in... more Cystic echinococcosis (CE) is one of the most common zoonotic diseases worldwide, particularly in rural areas. This study aimed at the identification of the genotype/species belonging to Echinococcus granulosus sensu lato (s.l.) specimens in retrieved percutaneously from the human host and to investigate their relationship with cyst characteristics. The genetic identification of cyst material was performed by mt-CO1 gene polymerase chain reaction, and confirmed via sequencing. A total of 110 CE cysts were identified as E. granulosus s.l. In detail, 104 belonged to E. granulosus sensu stricto (G1 and G3) and six isolates were in the E. canadensis cluster (G6/7). All clusters were tested for the relationship between demographics, cyst features and genetic diversity. The relationship between genetic variation and certain clinical characteristics such as cyst volume and location were statistically significant for G6/7 cluster. Further studies are required with a larger sample set to inv...
JPMA. The Journal of the Pakistan Medical Association, 2016
Aggregatibacter aphrophilus rarely causes brain abscesses. Here we report a case of the brain abs... more Aggregatibacter aphrophilus rarely causes brain abscesses. Here we report a case of the brain abscess caused by Aggregatibacter aphrophilus. Cultivated gram negative coccobacilli from cerebral abscess were initially misidentified as Brucella spp. because it gave false positive agglutination with anti-Brucella sera. Definite identification was made with MALDI-TOF assay. Right to left shunt through the pulmonary arteriovenous malformation was speculated to be the underlying cause for the brain abscess. The patient was treated successfully with ampicillin-sulbactam after failing ceftriaxone treatment.
The aim of this study was to investigate the frequency of intestinal parasites in patients with c... more The aim of this study was to investigate the frequency of intestinal parasites in patients with chronic diarrhea and clarify the importance of these parasitic pathogens in such cases. A total of 60 pediatric patients with chronic diarrhea between June 2012 and October 2014 were enrolled in the study. Out of 60 stool samples, five were positive for Giardia lamblia, two, Dientamoeba fragilis, and one, Blastocystis hominis. One stool sample was positive for Entamoeba hartmanni and B. hominis, another one was positive for G. lamblia and B. hominis, another, G. lamblia and E. hartmanni and one sample was positive for Enterobius vermicularis, D. fragilis and B. hominis together. Parasitic infection, which decreases quality of life and increases susceptibility to other infections, should not be neglected, particularly in patients with chronic diarrhea. Accurate diagnosis decreases morbidity and mortality in patients with parasite infection.
Helicobacter pylori is a gram-negative, microaerophilic bacterium that colonizes human gastric mu... more Helicobacter pylori is a gram-negative, microaerophilic bacterium that colonizes human gastric mucosa and affects approximately 50% of the whole world population. It has put the blame on gastric ulcer, duodenal ulcer, chronic atrophic gastritis, mucosa-associated lymphoid tissue lymphoma and stomach adenocarcinoma, as the etiological agent. The cagA (cytotoxin-associated gene A) gene which is one of the most important virulence factors of H.pylori, encodes a 120-145 kDa protein called CagA antigen that may cause cell transformation. The prevalence of cagA positive H.pylori infections varies according to geographical area and age of the patients. Recent studies have suggested that cagA positive H.pylori strains play a role in the development of gastric carcinoma. The aim of this study was to evaluate the prevalence of cagA positive H.pylori isolates in adult and pediatric patient groups in Hacettepe University, Faculty of Medicine. The study was performed on 198 H.pylori stocked stra...
This study was aimed to adapt a sensitive DNA extraction protocol in stool samples for real-time ... more This study was aimed to adapt a sensitive DNA extraction protocol in stool samples for real-time polymerase chain reaction (PCR) detection of Entamoeba histolytica which causes important morbidity and mortality worldwide. Stool extraction is a problematic step and has direct effects on PCR sensitivity. In order to improve the sensitivity of E.histolytica detection by real-time PCR, "QIAamp DNA stool minikit (Qiagen, Germany)" was modified by adding an overnight incubation step with proteinase K and sodium dodecyl sulfate (SDS) in this study. Three different extraction methods [(1) original method, (2) cetyltrimethyl-ammonium bromide (CTAB) method, (3) modified method] were evaluated for effects on sensitivity in real-time quantitative PCR (Artus RealArt TM E.histolytica RG PCR Kit, Qiagen Diagnostics, Germany). For this purpose, several concentrations of standard E.histolytica DNA were spiked in parasite-free stool samples and three different extraction protocols were perf...
Microsporidia are single celled, obligate intracellular, spore forming microorganisms which were ... more Microsporidia are single celled, obligate intracellular, spore forming microorganisms which were first described as a cause of human disease in 1959. They are capable of infecting a wide variety of vertebrate and invertebrate hosts. Among the numerous microsporidial genera, seven have been described in human diseases such as Enterocytozoon, Encephalitozoon, Nosema, Pleistophora, Trachipleistophora, Vittaforma, Brachiola. Among these, Enterocytozoon bieneusi is the most frequently identified microsporidian in the patients. Features used in identification include spore size, nuclear configuration of spores, the number of polar tubule coils and the parazite-host interaction. In the development of Microsporidia, there are two different phases, called as proliferative phase and sporogonic phase. The only stage of Microsporidia outside the host is infective spores. The microsporidial spore is highly specialized, environmentally resistant structure that varies in size and shape according t...
Candida species are opportunistic microorganisms which are members of the normal flora of the muc... more Candida species are opportunistic microorganisms which are members of the normal flora of the mucous membranes in the respiratory, gastrointestinal and female genital tracts. In the presence of suitable conditions, they may gain dominance and be associated with pathologic conditions 1. In the past 30 years, there has been a significant increase in the number of infections caused by Candida species 2.
Background. Helicobacter pylori infection is primarily acquired in childhood. However, the associ... more Background. Helicobacter pylori infection is primarily acquired in childhood. However, the association between H. pylori infection and recurrent abdominal pain (RAP) remains unclear.Materials and methods. One hundred and forty‐one children with and 21 without RAP underwent upper gastrointestinal endoscopy. At least five antral gastric biopsies were obtained from each patient and the presence of H. pylori infection was accepted when at least two out of four tests (histology, direct antral smear, culture, and rapid urease test) were positive. Patients with H. pylori infection underwent triple therapy with omeprazole, clarithromycin, and metronidazole.Results. Eighty‐five out of 141 (60.3%) patients with RAP were H. pylori positive whereas 5 out of 21 (20.8%) patients without RAP were (p = .0037). Symptoms were disappeared in 87% of children whose H. pylori infection was eradicated compared with 41% of those in whom the infection was not eradicated (p = .0035).Conclusions. It was concl...
The aim of this study was to compare different methods of detection of Helicobacter pylori (H. py... more The aim of this study was to compare different methods of detection of Helicobacter pylori (H. pylori) in the dental plaque of dyspeptic patients. After recording the clinical indices, culture and polymerase chain reaction (PCR) methods were performed on plaque samples, while rapid urease test in addition to these tests was carried on gastric samples from 67 dyspeptic patients who attended for an upper gastrointestinal endoscopy. Forty-seven of 67 patients were H. pylori-positive in gastric biopsy material whereas the microbial dental plaque from 19 patients demonstrated H. pylori positivity detected by PCR. Among the patients, 25.4% harbored H. pylori both in the stomach and in microbial dental plaque. No significant correlations were found among the presence of H. pylori in the stomach, in plaque, and clinical variables (P > 0.05). Although oral hygiene was observed optimal and the mean of pocket depth was not found to be higher, the prevalence of H. pylori was observed to be higher in dental plaque. According to our results, PCR technique gave the highest detection rate both in gastric biopsy and in dental plaque compared to the other methods used.
In this study,Staphylococcus aureusstrains (n = 110) isolated from seven ewe flocks in Sanliurfa,... more In this study,Staphylococcus aureusstrains (n = 110) isolated from seven ewe flocks in Sanliurfa, Turkey were screened for antibiotic resistance and biofilmforming ability as well as for genes associated with antibiotic resistance and biofilm-forming ability. All isolates were found to be susceptible to oxacillin, gentamicin, clindamycin, cefoxitin, tetracycline, vancomycin, amoxicillin-clavulanic acid, ciprofloxacin and sulphamethoxazole-trimethoprim. The percent proportions of strains resistant to penicillin G, ampicillin and erythromycin were 27.2% (n = 30), 25.4% (n = 28) and 6.3% (n = 7), respectively. Regarding the antibiotic resistance genes, 32 (29%) isolates carried theblaZ and 8 (7.2%) theermC gene. Other resistance genes were not detected in the isolates. All isolates showed biofilm-forming ability on Congo red agar (CRA), while 108 (98.18%) and 101 (91.81%) of them were identified as biofilm producers by the use of standard tube (ST) and microplate (MP) methods, respecti...
Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogeni... more Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogenic potentials are a matter of debate since their discovery. This study aims to investigate the relationship between the activation of ulcerative colitis (UC) and irritable bowel syndrome (IBS) with these protists. A total of 100 patients (35 IBS, 35 active UC, and 30 remittent UC), diagnosed at Hacettepe University Adult Hospital (Ankara, Turkey), were screened for D. fragilis and Blastocystis sp. with microscopic examination using the methods of wet mount, trichrome staining, conventional PCR, nested PCR, real-time PCR and genotyping. Eight patients (4 IBS, 2 active, and 2 remittent UC patients) were found to be D. fragilis positive. 18S rRNA region of the parasite was amplified in four of the patients, whereas cathepsin L-like cysteine peptidase, clan Sc, family S9, serine peptidase, and clan MH, family M20 metallopeptidase in six different patients. All isolates were Genotype 1 by sequencing. Sequence results showed very limited diversity. A total of nine patients (3 IBS, 5 active UC, 1 remittent UC) were found to be positive for Blastocystis sp., all of which were Subtype 3. One active UC and one IBS patient were found to be positive for both parasites. No statistically significant difference was detected between the patient groups for parasite detection. D. fragilis was found to be related to older age (p=0,045). In our study, no significant correlation was identified between D. fragilis and Blastocystis sp., and the activation of UC and IBS. More studies are needed on the host-parasite relationship, including the role of gut microbiota, together with transcriptomic and metabolomic assessments to unveil the pathogenicity of both protists.
E. Bellikci-Koyu, B.P. Sarer-Yurekli, Y. Akyon, A.G. Ozgen, A. Brinkmann, A. Nitsche, K. Ergunay,... more E. Bellikci-Koyu, B.P. Sarer-Yurekli, Y. Akyon, A.G. Ozgen, A. Brinkmann, A. Nitsche, K. Ergunay, E. Yilmaz, M. P. St-Onge and Z. Buyuktuncer Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, Turkey, Department of Nutrition and Dietetics, Faculty of Health Sciences, Izmir Katip Celebi University, Turkey, Department of Endocrinology, Faculty of Medicine, Ege University, Turkey, Department of Medical Microbiology, Faculty of Medicine, Hacettepe University, Turkey, Robert Koch Institute, Center for Biological Threats and Special Pathogens 1 (ZBS-1), Germany, Department of Medical Biology, Faculty of Medicine, Hacettepe University, Turkey (Retired Professor) and Sleep Center of Excellence & Division of General Medicine, Department of Medicine, Columbia University Irving Medical Center, New York, USA
The Journal of Clinical Endocrinology & Metabolism, 2020
Context Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder. Emerging ani... more Context Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder. Emerging animal and human data point to various changes in microbiota that could be linked with the syndrome. However, the effects of therapeutic approaches on gut microbial composition in women with PCOS remain unknown. Objective We aimed to assess whether gut microbial composition is altered in PCOS and to determine the potential impact of oral contraceptive (OC) use on gut microbiota. Design Prospective observational study. Setting Tertiary referral hospital. Patients and Other Participants The study included 17 overweight/obese patients with PCOS and 15 age- and body mass index-matched healthy control women. Main Outcome Measures At baseline, clinical, hormonal, and metabolic evaluations and gut microbial composition assessment by 16S rRNA gene amplicon sequencing were performed for both groups. All measurements were repeated in patients after receiving an OC along with general lifestyle advice ...
Cystic echinococcosis (CE) is one of the most common zoonotic diseases worldwide, particularly in... more Cystic echinococcosis (CE) is one of the most common zoonotic diseases worldwide, particularly in rural areas. This study aimed at the identification of the genotype/species belonging to Echinococcus granulosus sensu lato (s.l.) specimens in retrieved percutaneously from the human host and to investigate their relationship with cyst characteristics. The genetic identification of cyst material was performed by mt-CO1 gene polymerase chain reaction, and confirmed via sequencing. A total of 110 CE cysts were identified as E. granulosus s.l. In detail, 104 belonged to E. granulosus sensu stricto (G1 and G3) and six isolates were in the E. canadensis cluster (G6/7). All clusters were tested for the relationship between demographics, cyst features and genetic diversity. The relationship between genetic variation and certain clinical characteristics such as cyst volume and location were statistically significant for G6/7 cluster. Further studies are required with a larger sample set to inv...
JPMA. The Journal of the Pakistan Medical Association, 2016
Aggregatibacter aphrophilus rarely causes brain abscesses. Here we report a case of the brain abs... more Aggregatibacter aphrophilus rarely causes brain abscesses. Here we report a case of the brain abscess caused by Aggregatibacter aphrophilus. Cultivated gram negative coccobacilli from cerebral abscess were initially misidentified as Brucella spp. because it gave false positive agglutination with anti-Brucella sera. Definite identification was made with MALDI-TOF assay. Right to left shunt through the pulmonary arteriovenous malformation was speculated to be the underlying cause for the brain abscess. The patient was treated successfully with ampicillin-sulbactam after failing ceftriaxone treatment.
The aim of this study was to investigate the frequency of intestinal parasites in patients with c... more The aim of this study was to investigate the frequency of intestinal parasites in patients with chronic diarrhea and clarify the importance of these parasitic pathogens in such cases. A total of 60 pediatric patients with chronic diarrhea between June 2012 and October 2014 were enrolled in the study. Out of 60 stool samples, five were positive for Giardia lamblia, two, Dientamoeba fragilis, and one, Blastocystis hominis. One stool sample was positive for Entamoeba hartmanni and B. hominis, another one was positive for G. lamblia and B. hominis, another, G. lamblia and E. hartmanni and one sample was positive for Enterobius vermicularis, D. fragilis and B. hominis together. Parasitic infection, which decreases quality of life and increases susceptibility to other infections, should not be neglected, particularly in patients with chronic diarrhea. Accurate diagnosis decreases morbidity and mortality in patients with parasite infection.
Helicobacter pylori is a gram-negative, microaerophilic bacterium that colonizes human gastric mu... more Helicobacter pylori is a gram-negative, microaerophilic bacterium that colonizes human gastric mucosa and affects approximately 50% of the whole world population. It has put the blame on gastric ulcer, duodenal ulcer, chronic atrophic gastritis, mucosa-associated lymphoid tissue lymphoma and stomach adenocarcinoma, as the etiological agent. The cagA (cytotoxin-associated gene A) gene which is one of the most important virulence factors of H.pylori, encodes a 120-145 kDa protein called CagA antigen that may cause cell transformation. The prevalence of cagA positive H.pylori infections varies according to geographical area and age of the patients. Recent studies have suggested that cagA positive H.pylori strains play a role in the development of gastric carcinoma. The aim of this study was to evaluate the prevalence of cagA positive H.pylori isolates in adult and pediatric patient groups in Hacettepe University, Faculty of Medicine. The study was performed on 198 H.pylori stocked stra...
This study was aimed to adapt a sensitive DNA extraction protocol in stool samples for real-time ... more This study was aimed to adapt a sensitive DNA extraction protocol in stool samples for real-time polymerase chain reaction (PCR) detection of Entamoeba histolytica which causes important morbidity and mortality worldwide. Stool extraction is a problematic step and has direct effects on PCR sensitivity. In order to improve the sensitivity of E.histolytica detection by real-time PCR, "QIAamp DNA stool minikit (Qiagen, Germany)" was modified by adding an overnight incubation step with proteinase K and sodium dodecyl sulfate (SDS) in this study. Three different extraction methods [(1) original method, (2) cetyltrimethyl-ammonium bromide (CTAB) method, (3) modified method] were evaluated for effects on sensitivity in real-time quantitative PCR (Artus RealArt TM E.histolytica RG PCR Kit, Qiagen Diagnostics, Germany). For this purpose, several concentrations of standard E.histolytica DNA were spiked in parasite-free stool samples and three different extraction protocols were perf...
Microsporidia are single celled, obligate intracellular, spore forming microorganisms which were ... more Microsporidia are single celled, obligate intracellular, spore forming microorganisms which were first described as a cause of human disease in 1959. They are capable of infecting a wide variety of vertebrate and invertebrate hosts. Among the numerous microsporidial genera, seven have been described in human diseases such as Enterocytozoon, Encephalitozoon, Nosema, Pleistophora, Trachipleistophora, Vittaforma, Brachiola. Among these, Enterocytozoon bieneusi is the most frequently identified microsporidian in the patients. Features used in identification include spore size, nuclear configuration of spores, the number of polar tubule coils and the parazite-host interaction. In the development of Microsporidia, there are two different phases, called as proliferative phase and sporogonic phase. The only stage of Microsporidia outside the host is infective spores. The microsporidial spore is highly specialized, environmentally resistant structure that varies in size and shape according t...
Candida species are opportunistic microorganisms which are members of the normal flora of the muc... more Candida species are opportunistic microorganisms which are members of the normal flora of the mucous membranes in the respiratory, gastrointestinal and female genital tracts. In the presence of suitable conditions, they may gain dominance and be associated with pathologic conditions 1. In the past 30 years, there has been a significant increase in the number of infections caused by Candida species 2.
Background. Helicobacter pylori infection is primarily acquired in childhood. However, the associ... more Background. Helicobacter pylori infection is primarily acquired in childhood. However, the association between H. pylori infection and recurrent abdominal pain (RAP) remains unclear.Materials and methods. One hundred and forty‐one children with and 21 without RAP underwent upper gastrointestinal endoscopy. At least five antral gastric biopsies were obtained from each patient and the presence of H. pylori infection was accepted when at least two out of four tests (histology, direct antral smear, culture, and rapid urease test) were positive. Patients with H. pylori infection underwent triple therapy with omeprazole, clarithromycin, and metronidazole.Results. Eighty‐five out of 141 (60.3%) patients with RAP were H. pylori positive whereas 5 out of 21 (20.8%) patients without RAP were (p = .0037). Symptoms were disappeared in 87% of children whose H. pylori infection was eradicated compared with 41% of those in whom the infection was not eradicated (p = .0035).Conclusions. It was concl...
The aim of this study was to compare different methods of detection of Helicobacter pylori (H. py... more The aim of this study was to compare different methods of detection of Helicobacter pylori (H. pylori) in the dental plaque of dyspeptic patients. After recording the clinical indices, culture and polymerase chain reaction (PCR) methods were performed on plaque samples, while rapid urease test in addition to these tests was carried on gastric samples from 67 dyspeptic patients who attended for an upper gastrointestinal endoscopy. Forty-seven of 67 patients were H. pylori-positive in gastric biopsy material whereas the microbial dental plaque from 19 patients demonstrated H. pylori positivity detected by PCR. Among the patients, 25.4% harbored H. pylori both in the stomach and in microbial dental plaque. No significant correlations were found among the presence of H. pylori in the stomach, in plaque, and clinical variables (P > 0.05). Although oral hygiene was observed optimal and the mean of pocket depth was not found to be higher, the prevalence of H. pylori was observed to be higher in dental plaque. According to our results, PCR technique gave the highest detection rate both in gastric biopsy and in dental plaque compared to the other methods used.
In this study,Staphylococcus aureusstrains (n = 110) isolated from seven ewe flocks in Sanliurfa,... more In this study,Staphylococcus aureusstrains (n = 110) isolated from seven ewe flocks in Sanliurfa, Turkey were screened for antibiotic resistance and biofilmforming ability as well as for genes associated with antibiotic resistance and biofilm-forming ability. All isolates were found to be susceptible to oxacillin, gentamicin, clindamycin, cefoxitin, tetracycline, vancomycin, amoxicillin-clavulanic acid, ciprofloxacin and sulphamethoxazole-trimethoprim. The percent proportions of strains resistant to penicillin G, ampicillin and erythromycin were 27.2% (n = 30), 25.4% (n = 28) and 6.3% (n = 7), respectively. Regarding the antibiotic resistance genes, 32 (29%) isolates carried theblaZ and 8 (7.2%) theermC gene. Other resistance genes were not detected in the isolates. All isolates showed biofilm-forming ability on Congo red agar (CRA), while 108 (98.18%) and 101 (91.81%) of them were identified as biofilm producers by the use of standard tube (ST) and microplate (MP) methods, respecti...
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