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1.
Front Public Health ; 11: 1100280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778575

RESUMO

Background: Hospitals are institutions whose primary task is to treat patients. Family-centered care, which considers loved ones as equal partners in patient care, has been gaining recognition in the adult care setting. Our aim was to record experiences of and opinions on communication between hospital-based healthcare providers and patients' loved ones, related but not limited to the rigorous mitigation measures implemented during the COVID-19 pandemic. Methods: The Twitter profile @HospitalsTalkTo and hashtag #HospitalsTalkToLovedOnes were created to interact with the Twitter public between 7 June 2021 and 7 February 2022. Conversations surrounding #HospitalsTalkToLovedOnes were extracted and subjected to natural language processing analysis using term frequency and Markov chain analysis. Qualitative thematic analysis was performed on the 10% most interacted tweets and of tweets mentioning "COVID" from a personal experience-based subset. Results: We collected 4412 unique tweets made or interacted by 7040 Twitter users from 142 different countries. The most frequent words were patient, hospital, care, family, loved and communication. Thematic analysis revealed the importance of communication between patients, patients' loved ones and hospitals; showed that patients and their loved ones need support during a patient's hospital journey; and that pediatric care should be the gold standard for adult care. Visitation restrictions due to COVID-19 are just one barrier to communication, others are a lack of phone signal, no space or time for asking questions, and a complex medical system. We formulate 3 recommendations to improve the inclusion of loved ones into the patient's hospital stay. Conclusions: "Loved ones are not 'visitors' in a patient's life". Irrespective of COVID-19, patient's loved ones need to be included during the patient's hospital journey. Transparent communication and patient empowerment increase patient safety and improve the hospital experience for both the patients and their loved ones. Our findings underline the need for the concept of family-centered care to finally be implemented in adult nursing clinical practice.


Assuntos
COVID-19 , Mídias Sociais , Adulto , Criança , Humanos , Tempo de Internação , Pandemias , Comunicação
2.
Phytomedicine ; 108: 154520, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334386

RESUMO

BACKGROUND: The development of digital technologies and the evolution of open innovation approaches have enabled the creation of diverse virtual organizations and enterprises coordinating their activities primarily online. The open innovation platform titled "International Natural Product Sciences Taskforce" (INPST) was established in 2018, to bring together in collaborative environment individuals and organizations interested in natural product scientific research, and to empower their interactions by using digital communication tools. METHODS: In this work, we present a general overview of INPST activities and showcase the specific use of Twitter as a powerful networking tool that was used to host a one-week "2021 INPST Twitter Networking Event" (spanning from 31st May 2021 to 6th June 2021) based on the application of the Twitter hashtag #INPST. RESULTS AND CONCLUSION: The use of this hashtag during the networking event period was analyzed with Symplur Signals (https://www.symplur.com/), revealing a total of 6,036 tweets, shared by 686 users, which generated a total of 65,004,773 impressions (views of the respective tweets). This networking event's achieved high visibility and participation rate showcases a convincing example of how this social media platform can be used as a highly effective tool to host virtual Twitter-based international biomedical research events.


Assuntos
Produtos Biológicos , Mídias Sociais , Humanos
3.
Front Med (Lausanne) ; 9: 961360, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186802

RESUMO

Background: Crowdsourcing is a low-cost, adaptable, and innovative method to collect ideas from numerous contributors with diverse backgrounds. Crowdsourcing from social media like Twitter can be used for generating ideas in a noticeably brief time based on contributions from globally distributed users. The world has been challenged by the COVID-19 pandemic in the last several years. Measures to combat the pandemic continue to evolve worldwide, and ideas and opinions on optimal counteraction strategies are of high interest. Objective: This study aimed to validate the use of Twitter as a crowdsourcing platform in order to gain an understanding of public opinion on what measures can help to end the COVID-19 pandemic faster. Methods: This cross-sectional study was conducted during the period from December 22, 2021, to February 4, 2022. Tweets were posted by accounts operated by the authors, asking "How to faster end the COVID-19 pandemic?" and encouraging the viewers to comment on measures that they perceive would be effective to achieve this goal. The ideas from the users' comments were collected and categorized into two major themes - personal and institutional measures. In the final stage of the campaign, a Twitter poll was conducted to get additional comments and to estimate which of the two groups of measures were perceived to be important amongst Twitter users. Results: The crowdsourcing campaign generated seventeen suggested measures categorized into two major themes (personal and institutional) that received a total of 1,727 endorsements (supporting comments, retweets, and likes). The poll received a total of 325 votes with 58% of votes underscoring the importance of both personal and institutional measures, 20% favoring personal measures, 11% favoring institutional measures, and 11% of the votes given just out of curiosity to see the vote results. Conclusions: Twitter was utilized successfully for crowdsourcing ideas on strategies how to end the COVID-19 pandemic faster. The results indicate that the Twitter community highly values the significance of both personal responsibility and institutional measures to counteract the pandemic. This study validates the use of Twitter as a primary tool that could be used for crowdsourcing ideas with healthcare significance.

4.
JMIR Form Res ; 6(6): e35754, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35617671

RESUMO

BACKGROUND: On January 30, 2020, the World Health Organization Emergency Committee declared the rapid worldwide spread of COVID-19 a global health emergency. By December 2020, the safety and efficacy of the first COVID-19 vaccines had been demonstrated. However, international vaccination coverage rates have remained below expectations (in Europe at the time of manuscript submission). Controversial mandatory vaccination is currently being discussed and has already been introduced in some countries (Austria, Greece, and Italy). We used the Twitter survey system as a viable method to quickly and comprehensively gather international public health insights on mandatory vaccination against COVID-19. OBJECTIVE: The purpose of this study was to better understand the public's perception of mandatory COVID-19 vaccination in real time using Twitter polls. METHODS: Two Twitter polls were developed (in the English language) to seek the public's opinion on the possibility of mandatory vaccination. The polls were pinned to the Digital Health and Patient Safety Platform's (based in Vienna, Austria) Twitter timeline for 1 week in mid-November 2021, 3 days after the official public announcement of mandatory COVID-19 vaccination in Austria. Twitter users were asked to participate and retweet the polls to reach the largest possible audience. RESULTS: Our Twitter polls revealed two extremes on the topic of mandatory vaccination against COVID-19. Almost half of the 2545 respondents (n=1246, 49%) favor mandatory vaccination, at least in certain areas. This attitude contrasts with the 45.7% (n=1162) who categorically reject mandatory vaccination. Over one-quarter (n=621, 26.3%) of participating Twitter users said they would never get vaccinated, as reflected by the current Western European and North American vaccination coverage rate. Concatenating interpretation of these two polls should be done cautiously as participating populations might substantially differ. CONCLUSIONS: Mandatory vaccination against COVID-19 (in at least certain areas) is favored by less than 50%, whereas it is opposed by almost half of the surveyed Twitter users. Since (social) media strongly influences public perceptions and views, and social media discussions and surveys are specifically susceptible to the "echo chamber effect," the results should be interpreted as a momentary snapshot. Therefore, the results of this study need to be complemented by long-term surveys to maintain their validity.

5.
J Antimicrob Chemother ; 73(6): 1595-1603, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29566160

RESUMO

Objectives: Because of the rise in antimicrobial resistance, an inexpensive, diet-based treatment against Helicobacter pylori infection would be of great interest. The present study was performed to assess the in vitro effects of ellagic acid against clinical H. pylori strains that were resistant to antibiotics used for therapy and also to observe the morphological structure following treatment with ellagic acid. The effectiveness of ellagic acid in eradicating H. pylori infection in a murine (C57BL/6) infection model, one of the standard inbred mouse lines often used for experimental infection, was also assessed. Methods: A total of 55 strains were screened. The agar dilution method was used to determine the susceptibility of isolates to test compounds. Transmission electron microscopy was used to observe the morphology following treatment with ellagic acid. The antibacterial activity of ellagic acid in an H. pylori SS1-infected mouse model and its effect on gastric mucosal injury were determined by histology and PCR. Results: Ellagic acid inhibited the growth of all 55 of the H. pylori strains tested. The MIC of ellagic acid ranged from 5 to 30 mg/L, showing its bactericidal properties in vitro. Ellagic acid also demonstrated anti-H. pylori efficacy in eradication of this organism in an in vivo model, as well as restitution and repair of H. pylori-induced gastric mucosal damage. Conclusions: The present study paves the way for the preventive and therapeutic use of ellagic acid against H. pylori infection and, thus, ellagic acid can be considered a promising antibacterial agent against H. pylori-associated gastroduodenal diseases in humans.


Assuntos
Ácido Elágico/farmacologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Modelos Animais de Doenças , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/ultraestrutura , Humanos , Índia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Organismos Livres de Patógenos Específicos
6.
J Glob Antimicrob Resist ; 5: 51-6, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27436467

RESUMO

Helicobacter pylori-related gastroduodenal diseases are very common in India. Antibiotic resistance to commonly used antibiotics against H. pylori is increasing very rapidly. The aim of this study was to determine the antimicrobial susceptibility patterns of H. pylori strains from India against commonly used antibiotics in H. pylori treatment. Helicobacter pylori were cultured from 68 patients suffering from various gastroduodenal diseases in North India. Minimum inhibitory concentrations (MICs) to different antibiotics were determined by agar dilution. The clinical diagnosis of the 68 patients who were H. pylori culture-positive were gastro-oesophageal reflux disease (GERD) (n=23), non-erosive reflux disease (NERD) (n=22), non-ulcer dyspepsia (NUD) (n=13), antral gastritis (n=3), duodenal ulcer (n=2) and others (n=5). Of the 68 H. pylori isolates, 20 (29.4%) showed no resistance. The prevalence of drug resistance was 70.6%, including resistance to metronidazole (48.5%), furazolidone (22.1%), amoxicillin (17.6%), tetracycline (16.2%) and clarithromycin (11.8%). Dual and multiple drug resistance were found in 26.5% and 8.8% of cases, respectively. In conclusion, more than two-thirds of the isolated H. pylori strains showed resistance to at least one of the antibiotics for H. pylori treatment. Metronidazole resistance was most prevalent amongst the isolates tested. Emergence of dual and multidrug resistance is of great concern and there is an urgent need for regular antibiotic resistance surveillance studies. Amoxicillin- and clarithromycin-based anti-H. pylori regimens commonly prescribed for triple therapy in India show least resistance and hence are appropriate for anti-H. pylori management in India.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Helicobacter pylori/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Índia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Adulto Jovem
7.
Int J Biol Macromol ; 89: 622-31, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27177460

RESUMO

This study investigates the design of sunflower oil entrapped floating and mucoadhesive beads of amoxicillin trihydrate using sodium alginate and hydroxypropyl methylcellulose as matrix polymers and chitosan as coating polymer to localize the antibiotic at the stomach site against Helicobacter pylori. Beads prepared by ionotropic gellation technique were evaluated for different physicochemical, in-vitro and in-vivo properties. Beads of all batches were floated for >24h with a maximum lag time of 46.3±3.2s. Scanning electron microscopy revealed that the beads were spherical in shape with few oil filled channels distributed throughout the surfaces and small pocket structures inside the matrix confirming oil entrapment. Prepared beads showed good mucoadhesiveness of 75.7±3.0% to 85.0±5.5%. The drug release profile was best fitted to Higuchi model with non fickian driven mechanism. The optimized batch showed 100% Helicobacter pylori growth inhibition in 15h in in-vitro culture. Furthermore, X-ray study in rabbit stomach confirmed the gastric retention of optimized formulation. The results exhibited that formulated beads may be preferred to localize the antibiotic in the gastric region to allow more availability of antibiotic at gastric mucus layer acting on Helicobacter pylori, thereby improving the therapeutic efficacy.


Assuntos
Alginatos/administração & dosagem , Amoxicilina/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Alginatos/química , Amoxicilina/química , Animais , Quitosana/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/química , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/química , Humanos , Derivados da Hipromelose/química , Óleos de Plantas/química , Óleos de Plantas/uso terapêutico , Coelhos , Estômago/efeitos dos fármacos , Estômago/microbiologia , Estômago/patologia , Óleo de Girassol
8.
World J Gastroenterol ; 22(9): 2736-48, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26973412

RESUMO

Curcumin, a yellow pigment and principal polyphenolic Curcuminoid obtained from the turmeric rhizome Curcuma longa, is commonly used as a food-coloring agent. Studies suggest that curcumin has a wide range of beneficial properties e.g., anti-inflammatory, anti-oxidant, anti-cancer, anti-proliferative, anti-fungal and anti-microbial. These pleiotropic activities prompted several research groups to elucidate the role of curcumin in Helicobacter pylori (H. pylori) infection. This is the first review with this heading where we discussed regarding the role of curcumin as an anti-H. pylori agent along with its potential in other gastrointestinal diseases. Based on several in vitro, early cell culture, animal research and few pre-clinical trials, curcumin projected as a potential therapeutic candidate against H. pylori mediated gastric pathogenesis. This review sheds light on the anti-H. pylori effects of curcumin in different models with meticulous emphasis on its anti-oxidant, anti-inflammatory and anti-carcinogenic effects as well as some critical signaling and effecter molecules. Remarkably, non-toxic molecule curcumin fulfills the characteristics for an ideal chemopreventive agent against H. pylori mediated gastric carcinogenesis but the foremost challenge is to obtain the optimum therapeutic levels of curcumin, due to its low solubility and poor bioavailability. Further, we have discussed about the possibilities for improving its efficacy and bioavailability. Lastly, we concluded with the anticipation that in near future curcumin may be used to develop a therapeutic drug against H. pylori mediated gastric ailments through improved formulation or delivery systems, facilitating its enhanced absorption and cellular uptake.


Assuntos
Antibacterianos/uso terapêutico , Anticarcinógenos/uso terapêutico , Curcumina/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Neoplasias Gástricas/prevenção & controle , Animais , Antibacterianos/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Anticarcinógenos/efeitos adversos , Antioxidantes/uso terapêutico , Curcumina/efeitos adversos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/microbiologia , Resultado do Tratamento
9.
Gut Pathog ; 8: 10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27006705

RESUMO

BACKGROUND: Almost all Helicobacter pylori infected person develop gastritis and severe gastritis is supposed to be the denominator of peptic ulcer diseases, which may lead to gastric cancer. However, it is still an enigma why few strains are associated with ulcer formation, while others are not related with any disease outcome. Although a number of putative virulence factors have been reported for H. pylori, there are contradictory results regarding their connotation with diseases. Recently, there has been a significant attention in strain-specific genes outside the cag pathogenicity island, especially genes within plasticity regions. Studies demonstrated that certain genes in this region may play important roles in the pathogenesis of H. pylori-associated diseases. The aim of this study was to assess the role of selected genes (jhp0940, jhp0945, jhp0947 and jhp0949) in the plasticity region in relation to risk of H. pylori-related diseases in Indian population. METHODS: A total of 113 H. pylori strains isolated from duodenal ulcer (DU) (n = 61) and non-ulcer dyspepsia (NUD) subjects (n = 52) were screened by PCR and Dot-Blot to determine the presence of these genes. The comparative study of IL-8 production and apoptosis were also done by co-culturing the AGS cells with H. pylori strains of different genotype. RESULTS: PCR and Dot-Blot results indicated that the prevalence rates of jhp0940, jhp0945, jhp0947 and jhp0949 in the H. pylori strains were 9.8, 47.5, 50.8, 40.9 % and 17.3, 28.8, 26.9, 19.2 % isolated from DU and NUD, respectively. IL-8 production and apoptotic cell death were significantly higher in H. pylori strains containing jhp0945, jhp0947 and jhp0949 than the strains lacking those genes. Results indicated that the prevalence of jhp0945, jhp0947 and jhp0949 are associated with increased risk of severe diseases in India. CONCLUSION: Our study showed that presence of jhp0945, jhp0947 and jhp0949 were significantly associated with symptomatic expressions along with the increased virulence during in vitro study whereas jhp0940 seems to be negatively associated with the disease. These results suggest that jhp0945, jhp0947 and jhp0949 could be useful prognostic markers for the development of duodenal ulcer in India.

10.
Gut Pathog ; 8: 1, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26759607

RESUMO

BACKGROUND: The babA2 gene along with the cagA and vacA of Helicobacter pylori has been considered as a risk factor for the disease outcome in certain populations. This study was aimed to understand the role of babA2 of H. pylori with the background of cagA and vacA in disease manifestations in Indian sub population. METHODS: A total of 114 H. pylori strains isolated from duodenal ulcer (DU) (n = 53) and non-ulcer dyspepsia (NUD) patients (n = 61) were screened for the prevalence of these virulence markers by PCR. The comparative study of IL-8 production and apoptosis were done by co-culturing the AGS cell line with H. pylori strains with different genotypes. Adherence assay was performed with babA2 positive and negative strains. Two isogenic mutants of babA2 were constructed and the aforesaid comparative studies were carried out. RESULTS: PCR results indicated that 90.6 % (48/53), 82 % (50/61) and 73.6 % (39/53) strains from DU patients were positive for cagA, vacA, and babA2, respectively. Whereas the prevalence of these genes in NUD subjects were 70.5 % (43/61); 69.8 % (37/53), and 65.6 % (39/61), respectively. Although adherence to AGS cells was comparable among strains with babA2 positive and negative genotypes, but the triple positive strains could induce highest degree of IL-8 production and apoptosis, followed by the cagA (-)/vacA (-)/babA2 (+) strains and triple negative strains, respectively. The wild type strains showed significantly higher IL-8 induction as well as apoptosis in ex vivo than its isogenic mutant of babA2. CONCLUSION: PCR study demonstrated that there was no significant association between the distribution of babA2 genotype or of triple positive strains and disease outcome in this sub population. The adherence assay showed that there was no significant difference in the extent of adherence to AGS cells among babA2 positive and negative strains. But the ex vivo study indicated that the triple positive or even the babA2 only positive strains are involved in increased virulence. The wild type strains also exhibited increased virulence compared to the babA2 mutant strains. This inconsistency demonstrated that bacterial genotype along with host genetic polymorphisms or other factors play important role in determining the clinical manifestation of H. pylori infections.

11.
Gut Pathog ; 7: 9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25829953

RESUMO

BACKGROUND: The duodenal ulcer promoting gene (dupA) and dupA cluster in Helicobacter pylori have been described as a risk factor for duodenal ulcer development in some populations. Polymorphic gene dupA can be divided into two groups, intact dupA1 (long or short type based on the presence or absence of 615-bp extra sequences at the 5' region) having complete reading frame and other truncated dupA2 having frame-shift mutation. This study was aimed to elucidate the role of dupA of H. pylori and their clusters in the disease manifestation of Indian population. METHODS: A total of 170 H. pylori strains were screened for the presence of dupA, dupA alleles and dupA cluster by PCR and sequencing. Pro-inflammatory cytokine (IL-8) with different dupA variant H. pylori stimulated gastric epithelial cells (AGS cells) was measured by ELISA. RESULTS: A total of 50 strains (29.4%) were positive for dupA among the tested 170 strains. The prevalence of dupA1 in duodenal ulcer (DU) and non-ulcer dyspepsia (NUD) populations was found to be 25.5% (25/98) and 11.1% (8/72), respectively and 16.4% (28/170) of the tested strains had dupA1, cagA and vacAs1m1 positive. The distribution of long and short type dupA1 has not been significantly associated with the disease outcome. The dupA cluster analysis showed that 10.2% (10/98) and 8.3% (6/72) strains were positive among DU and NUD, respectively. IL-8 production was significantly higher in dupA1(+) , cagA (+), vacA (+) (902.5 ± 79.01 pg/mL) than dupA2 (+) , cagA (+) , vacA (+) (536.0 ± 100.4 pg/mL, P = 0.008) and dupA (-), cagA (+), vacA (+) (549.7 ± 104.1 pg/mL, P = 0.009). Phylogenetic analysis of dupA indicated that the Indian H. pylori strains clustered with East Asian strains but distinct from Western strains. This is the first known genetic element of Indian H. pylori that is genetically closer to the East Asian strains but differed from the Western strains. CONCLUSIONS: The intact dupA1 was significantly associated with DU than NUD (P = 0.029) but the dupA1 cluster has no role in the disease manifestation at India (P = 0.79). Thus, dupA1 can be considered as a biomarker for DU patients in India.

12.
J Bacteriol ; 194(21): 5963-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23045484

RESUMO

The prevalence of different H. pylori genotypes in various geographical regions indicates region-specific adaptations during the course of evolution. Complete genomes of H. pylori from countries with high infection burdens, such as India, have not yet been described. Herein we present genome sequences of two H. pylori strains, NAB47 and NAD1, from India. In this report, we briefly mention the sequencing and finishing approaches, genome assembly with downstream statistics, and important features of the two draft genomes, including their phylogenetic status. We believe that these genome sequences and the comparative genomics emanating thereupon will help us to clearly understand the ancestry and biology of the Indian H. pylori genotypes, and this will be helpful in solving the so-called Indian enigma, by which high infection rates do not corroborate the minuscule number of serious outcomes observed, including gastric cancer.


Assuntos
DNA Bacteriano/química , DNA Bacteriano/genética , Ordem dos Genes , Genoma Bacteriano , Helicobacter pylori/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise por Conglomerados , Úlcera Duodenal/complicações , Úlcera Duodenal/microbiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Índia , Dados de Sequência Molecular , Filogenia , Estados Unidos
13.
PLoS One ; 7(8): e43370, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22952670

RESUMO

Helicobacter pylori is one of the most diverse bacterial species that chronically infects more than 70% of Indian population. Interestingly, data showing microdiversity of the H. pylori strains within a particular gastric niche remained scarce. To understand the extent of genetic diversity among H. pylori strains within a given host, 30 patients with gastro-duodenal problems were subjected to endoscopy and from each patient 10 single colonies were isolated. Characterization of each of these 10 single colonies by DNA fingerprinting as well as genotyping of several important genetic markers viz. cagA, vacA, iceA, vapD, cag PAI empty site, IS605, RFLP and two other genetic segments within cag PAI revealed that all of the 30 patients were infected with more than one strain and sometimes strains with 5 to 6 types of genetic variants. Analyses of certain genetic loci showed the microdiversity among the colonies from single patient, which may be due to the recombination events during long-term carriage of the pathogen. These results suggest that most of the patients have acquired H. pylori due to repeated exposure to this pathogen with different genetic make-up, which may increase the possibility of super infections. Genetic exchanges between these unrelated H. pylori strains may support certain H. pylori variant to grow better in a given host than the parental strain and thereby increasing the possibility for the severity of the infection.


Assuntos
Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Antígenos de Bactérias , Biodiversidade , Primers do DNA/genética , Duodeno/microbiologia , Endoscopia/métodos , Marcadores Genéticos , Variação Genética , Genótipo , Humanos , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Recombinação Genética , Análise de Sequência de DNA , Estômago/microbiologia , Virulência
14.
J Med Microbiol ; 61(Pt 9): 1295-1302, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22653921

RESUMO

A novel virulence factor, duodenal ulcer-promoting gene A (dupA), in Helicobacter pylori has been found to be associated with disease in certain populations but not in others. This study analysed a South-east Indian population as part of the debate about the relevance of dupA for the prediction of clinical outcomes. A total of 140 H. pylori strains isolated from duodenal ulcer (DU) (n = 83) and non-ulcer dyspepsia (NUD) patients (n = 57) were screened by PCR and dot-blot hybridization to determine the presence of the ORFs jhp0917 and jhp0918. Part of jhp0917-jhp0918 was sequenced to search for the C/T insertion that characterizes dupA and the levels of dupA transcripts were also assessed. The PCR and dot-blot results indicated the presence of jhp0917 and jhp0918 in 37.3 % (31/83) and 12.2 % (7/57) of H. pylori strains isolated from DU and NUD patients, respectively. Sequencing analysis showed insertion of a C at nt 1386 in the 3' region of jhp0917, forming the dupA gene in 35 strains. RT-PCR analysis detected the dupA transcript in 28 of these 35 strains. The expression level of the dupA transcript varied from strain to strain, as shown by real-time PCR. The results demonstrated that analysis based on PCR only for dupA may produce an erroneous interpretation. The prevalence of dupA was significantly greater among strains isolated from patients with DU than from patients with NUD in this population (P = 0.001, odds ratio = 4.26, confidence interval = 1.60-11.74). Based on these findings, dupA can be considered a biomarker for DU patients in India. The reported discrepancies for this putative virulence marker in different populations may be due to the genome plasticity of H. pylori.


Assuntos
Úlcera Duodenal/microbiologia , Genes Bacterianos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Fatores de Virulência/genética , Adulto , Idoso , Sequência de Bases , Úlcera Duodenal/epidemiologia , Feminino , Regulação Bacteriana da Expressão Gênica , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise de Sequência de DNA , Adulto Jovem
15.
Gut Pathog ; 4(1): 4, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22631862

RESUMO

BACKGROUND: Infection with Helicobacter pylori strains that express CagA is associated with gastritis, peptic ulcer disease, and gastric adenocarcinoma. The biological function of CagA depends on tyrosine phosphorylation by a cellular kinase. The phosphate acceptor tyrosine moiety is present within the EPIYA motif at the C-terminal region of the protein. This region is highly polymorphic due to variations in the number of EPIYA motifs and the polymorphism found in spacer regions among EPIYA motifs. The aim of this study was to analyze the polymorphism at the C-terminal end of CagA and to evaluate its association with the clinical status of the host in West Bengal, India. RESULTS: Seventy-seven H. pylori strains isolated from patients with various clinical statuses were used to characterize the C-ternimal polymorphic region of CagA. Our analysis showed that there is no correlation between the previously described CagA types and various disease outcomes in Indian context. Further analyses of different CagA structures revealed that the repeat units in the spacer sequences within the EPIYA motifs are actually more discrete than the previously proposed models of CagA variants. CONCLUSION: Our analyses suggest that EPIYA motifs as well as the spacer sequence units are present as distinct insertions and deletions, which possibly have arisen from extensive recombination events. Moreover, we have identified several new CagA types, which could not be typed by the existing systems and therefore, we have proposed a new typing system. We hypothesize that a cagA gene encoding higher number EPIYA motifs may perhaps have arisen from cagA genes that encode lesser EPIYA motifs by acquisition of DNA segments through recombination events.

16.
PLoS One ; 6(1): e16306, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21283694

RESUMO

Current therapy-regimens against Helicobacter pylori (Hp) infections have considerable failure rates and adverse side effects that urge the quest for an effective alternative therapy. We have shown that curcumin is capable of eradicating Hp-infection in mice. Here we examine the mechanism by which curcumin protects Hp infection in cultured cells and mice. Since, MMP-3 and -9 are inflammatory molecules associated to the pathogenesis of Hp-infection, we investigated the role of curcumin on inflammatory MMPs as well as proinflammatory molecules. Curcumin dose dependently suppressed MMP-3 and -9 expression in Hp infected human gastric epithelial (AGS) cells. Consistently, Hp-eradication by curcumin-therapy involved significant downregulation of MMP-3 and -9 activities and expression in both cytotoxic associated gene (cag)(+ve) and cag(-ve) Hp-infected mouse gastric tissues. Moreover, we demonstrate that the conventional triple therapy (TT) alleviated MMP-3 and -9 activities less efficiently than curcumin and curcumin's action on MMPs was linked to decreased pro-inflammatory molecules and activator protein-1 activation in Hp-infected gastric tissues. Although both curcumin and TT were associated with MMP-3 and -9 downregulation during Hp-eradication, but unlike TT, curcumin enhanced peroxisome proliferator-activated receptor-γ and inhibitor of kappa B-α. These data indicate that curcumin-mediated healing of Hp-infection involves regulation of MMP-3 and -9 activities.


Assuntos
Curcumina/farmacologia , Inibidores Enzimáticos/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Animais , Células Cultivadas , Curcumina/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Humanos , Inflamação , Mediadores da Inflamação , Camundongos , Estômago/patologia
17.
Int J Med Microbiol ; 301(4): 293-302, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21195664

RESUMO

Several genes including the cagA in the cag pathogenicity island (cag PAI) of Helicobacter pylori are thought to be associated with the gastroduodenal diseases and hence variation in the genetic structure of the cag PAI might be responsible for different clinical outcomes. Our study was undertaken to characterize the cag PAI of H. pylori strains from duodenal ulcer (DU) patients and asymptomatic or non-ulcer dyspepsia (NUD/AV) subjects from Kolkata, India. Strains isolated from 52 individuals (30DU and 22NUD/AV) were analyzed by PCR using 83 different primers for the entire cag PAI and also by dot-blot hybridization. Unlike H. pylori strains isolated from other parts of India, 82.6% of the strains used in this study had intact cag PAI, 9.6% had partially deleted cag PAI, and 7.7% of the strains lacked the entire cag PAI. Dot-blot hybridization yielded positive signals in 100% and 93.8% of PCR-negative strains for HP0522-523 and HP0532-HP0534 genes, respectively. An intact cagA promoter region was also detected in all cagA-positive strains. Furthermore, the expression of cagA mRNA was confirmed by RT-PCR for the representative strains from both DU and NUD/AV subjects indicating the active cagA promoter regions of these strains. A total of 66.7% of Kolkata strains produced a ∼390-bp shorter amplicon than the standard strain 26695 for the HP0527 gene, homologue of virB10. However, sequence analyses confirmed that the deletion did not alter the reading frame of the gene, and mRNA transcripts were detected by RT-PCR analysis. The strains isolated from DU and NUD/AV express CagA protein and possess a functional type IV secretion system, as revealed by Western blot analyses. Interestingly, no significant differences in cag PAI genetic structure were found between DU and NUD/AV individuals suggesting that other bacterial virulence factors, host susceptibility, and environmental determinants also influence the disease outcome at least in certain geographical locations.


Assuntos
Ilhas Genômicas , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Adulto , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Portador Sadio/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Úlcera Duodenal/microbiologia , Feminino , Helicobacter pylori/isolamento & purificação , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Fatores de Virulência/genética
18.
Gut Pathog ; 2(1): 6, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20602767

RESUMO

Helicobacter pylori is one of the most genetically diverse of bacterial species, and since the 5'-end of cagA gene and the middle allele of vacA gene of H. pylori from different populations exhibit considerable polymorphisms, these sequence diversities were used to gain insights into the genetic affinities of this gastric pathogen from different populations. Because the genetic affinity of Arab strains from the Arabian Gulf is not known, we carried out genetic analysis based on sequence diversities of the cagA and the vacA genes of H. pylori from 9 ethnic Arabs in Kuwait. The analysis showed that the Kuwaiti isolates are closely related to the Indo-European group of strains, although some strains have a tendency to form a separate cluster close to the Indo- European group, but clearly distinct from East Asian strains. However, these results need to be confirmed by analyses of neutral markers (house-keeping genes in a multi-locus sequence typing [MLST]) platform. The profiling of virulence-associated genes may have resulted from ecologically distinct populations due to human migration and geographical separation over long periods of time.

19.
World J Gastroenterol ; 15(9): 1105-12, 2009 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-19266604

RESUMO

AIM: To investigate the changing pattern of different histological parameters occurring in the stomach tissue of Helicobacter pylori (H pylori) infected tribal populations and duodenal ulcer patients among ethnic Bengalis and correlation of the genotypes of H pylori with different histological parameters. METHODS: One hundred and twelve adult individuals were enrolled into this study between 2002 and 2004. Among them, 72 had clinical features of duodenal ulcer (DU) from ethnic Bengali population and 40 were asymptomatic ethnic tribals. Endoscopic gastric biopsy samples were processed for histology, genotyping and rapid urease test. Histologically, haematoxylin and eosin staining was applied to assess the pathomorphological changes and a modified Giemsa staining was used for better detection of H pylori. For intestinal metaplasia, special stainings, i.e. Alcian blue periodic acid-Schiff and high iron diamine-Alcian blue staining, were performed. PCR was performed on bacterial DNA to characterize the presence or absence of virulence-associated genes, like cagA, and distribution of different alleles of vacA and iceA. RESULTS: Intraglandular neutrophil infiltration, a hallmark of activity of gastritis, was present in 34 (94%) of tribals (TRs) and 42 (84%) of DU individuals infected with H pylori. Lymphoid follicles and aggregates, which are important landmarks in H pylori infection, were positive amongst 15 (41%) of TRs and 20 (40%) of DU subjects. Atrophic changes were observed in 60% and 27.7%, respectively, among DU cases and tribals (P > 0.003). Metaplastic changes were detected in low numbers in both groups. Moderate to severe density distribution of H pylori in the gastric mucosa was 63% among TRs, whereas it was 62% in DU subjects. There were no significant differences in the distribution of virulence-associated genes like cagA, vacA and iceA of H pylori strains carried by these two populations. CONCLUSION: Our study showed almost similar distribution of inflammatory cells among asymptomatic tribals and DU Bengali patients. Interestingly, the tribal population are free from any clinical symptoms despite evidence of active histologic gastritis and infection with H pylori strains carrying similar virulence markers as of strains isolated from patients with DU. There was an increased cellular response, especially in terms of neutrophil infiltration, but much lower risk of developing atrophy and metaplastic changes among the tribal population.


Assuntos
Úlcera Duodenal/patologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Atrofia , Primers do DNA , Diagnóstico Diferencial , Etnicidade , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Índia , Linfócitos/patologia , Reação em Cadeia da Polimerase
20.
Antimicrob Agents Chemother ; 53(4): 1592-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19204190

RESUMO

Treatment failure is a major cause of concern for the Helicobacter pylori-related gastroduodenal diseases like gastritis, peptic ulcer, and gastric cancer. Curcumin, diferuloylmethane from turmeric, has recently been shown to arrest H. pylori growth. The antibacterial activity of curcumin against 65 clinical isolates of H. pylori in vitro and during protection against H. pylori infection in vivo was examined. The MIC of curcumin ranges from 5 microg/ml to 50 microg/ml, showing its effectiveness in inhibiting H. pylori growth in vitro irrespective of the genetic makeup of the strains. The nucleotide sequences of the aroE genes, encoding shikimate dehydrogenase, against which curcumin seems to act as a noncompetitive inhibitor, from H. pylori strains presenting differential curcumin MICs showed that curcumin-mediated growth inhibition of Indian H. pylori strains may not be always dependent on the shikimate pathway. The antimicrobial effect of curcumin in H. pylori-infected C57BL/6 mice and its efficacy in reducing the gastric damage due to infection were examined histologically. Curcumin showed immense therapeutic potential against H. pylori infection as it was highly effective in eradication of H. pylori from infected mice as well as in restoration of H. pylori-induced gastric damage. This study provides novel insights into the therapeutic effect of curcumin against H. pylori infection, suggesting its potential as an alternative therapy, and opens the way for further studies on identification of novel antimicrobial targets of curcumin.


Assuntos
Antibacterianos/farmacologia , Curcumina/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Animais , Sequência de Bases , Curcumina/uso terapêutico , Infecções por Helicobacter/patologia , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Estômago/microbiologia , Estômago/patologia
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