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1.
BMC Infect Dis ; 24(1): 348, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528471

RESUMEN

BACKGROUND: Pakistan witnessed five waves of COVID-19 infections during the pandemic. Punjab, the largest province of Pakistan, remained the epicentre due to a high infection rate. Administrative data for five waves of the pandemic was analyzed to determine the rate of infections and the significance of pharmacological and non-pharmacological interventions on the severity and duration of infection. METHODOLOGY: COVID-19 data from March 2020 to May 2023 was obtained from the Provincial Public Health Reference Laboratory (PPHRL), Punjab AIDS Control Program, Lahore. The data included samples from index cases, contacts, and recovered patients. A total of 36,252,48 cases were screened for COVID-19, and 90,923 (2.50%) were detected positive by RT-PCR, accounting for 5.69% of the cases reported positive throughout the country. RESULTS: Among the positive cases, 50.86% (n = 46,244) cases were new cases (registered for the first time), 40.41% (n = 36751) were the contact cases traced from the newly identified cases and 8.62% (n = 7842) repeated cases. The positivity rates among index cases were reported to be 2.37%, 2.34%, 4.61%, 2.09%, and 1.19%, respectively, for the five respective COVID-19 pandemic waves. Distribution by gender indicated that 64% of males and 35% of females were infected during the pandemic. The age factor demonstrated the most susceptibility to infection in women aged 19-29 years, whereas most males between the ages of 29-39 had an infection. Susceptibility to COVID-19 infection was observed to be equally likely between males and females; however, clinical outcomes indicated that infections in males were more severe and often resulted in fatalities as compared to those in females. This trend was also reflected in the viral titer as measured by the Ct values, where 40% of males had Ct values < 25 (an indicator of high viral titers) compared to 30% of females with Ct values < 25. CONCLUSION: Overall, our data indicated that infection rates remained stable throughout the pandemic except for 3rd wave, which showed a higher incidence of infection rate of 4%. Additionally, data showed a positive impact of masking, social distancing, and immunization, as indicated by the shorter window of high infection rates.


Asunto(s)
COVID-19 , Masculino , Humanos , Femenino , Adulto , COVID-19/epidemiología , Pandemias/prevención & control , Factores de Edad , Pakistán/epidemiología , Inmunización
2.
Clin Infect Dis ; 77(Suppl 7): S569-S577, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38118009

RESUMEN

BACKGROUND: Efforts to combat antimicrobial resistance, a growing public health problem in Pakistan, have been hampered by the lack of high-quality national and provincial-level antimicrobial consumption data. The singular objective of this retrospective study was to measure antimicrobial consumption over 3 years between 2019 and 2021. METHODS: The study was designed to estimate antimicrobial consumption at National and Regional levels. Antimicrobial consumption data was collected by IQVIA covering 110 districts of Pakistan in which 88% of sales are census (accurate sales collected directly from distributors), whereas 12% of sales (sales of 300 pharmacies) are projected on the national level. To determine the usage for 3 consecutive years, the consumption of antibiotics was calculated as defined daily doses (DDD) of antibiotics per 1000 inhabitants per day (DID). RESULTS: The results of our study demonstrated a steep increase in the consumption of antimicrobials from 2019 to 2021. An increase in consumption of most classes of antibiotics was observed both nationally and Regionally. Quinolones, penicillins (co-amoxiclav), macrolides, and third-generation cephalosporins remained the most frequently used antibiotics nationally. A 40% increase in intravenous use of antimicrobials was observed between 2019 and 2021 at the national level. Moxifloxacin, Levofloxacin, Ciprofloxacin, and linezolid were the most commonly used intravenous antibiotics. Region 7 (Peshawar) demonstrated the highest consumption, followed by Region 1 (Karachi) and Region 6 (Faisalabad). Among the most commonly used antibiotics, the use of third-generation cephalosporin (cefixime), quinolones, penicillins (amoxicillin + clavulanic acid), and macrolides (azithromycin) was most noticeable in all regions, particularly in those with the higher consumption of antibiotics. CONCLUSIONS: Although the increase in consumption of all antibiotics is concerning, the steep increase in the use of watch and reserve category antibiotics during the study period calls for immediate actions to limit and regulate their usage.


Asunto(s)
Antiinfecciosos , COVID-19 , Humanos , Estudios Retrospectivos , Pakistán/epidemiología , Antibacterianos/uso terapéutico , Penicilinas , Ciprofloxacina , Macrólidos , Combinación Amoxicilina-Clavulanato de Potasio
3.
Cytokine ; 142: 155499, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33799008

RESUMEN

PURPOSE: The aim of this study was to explore the utility of inflammatory biomarkers in the peripheral blood to predict response to treatment in extrapulmonary tuberculosis (EPTB). METHODS: A Luminex xMAP-based multiplex immunoassay was used to measure 40 inflammatory biomarkers in un-stimulated plasma of 91 EPTB patients (48 lymphadenitis, and 43 pleuritis) before and at 2 and 6 months of treatment. RESULTS: Overall a significant change was observed in 28 inflammatory biomarkers with treatment in EPTB patients. However, MIG/CXCL9, IP-10/CXCL10, and CCL23 decreased in all patients' groups with successful treatment at both time points. At 2 months, 29/64 (45%) patients responded partially while 35/64 (55%) showed complete regress. Among good responders, a higher number of biomarkers (16/40) reduced significantly as compared to partial responders (1/40). Almost half (14/29) of partial responders required longer treatment than 6 months to achieve satisfactory response. The levels of MIG, IP-10, MIF, CCL22 and CCL23 reduced significantly among 80, 74, 60, 71, 51% good responders, as compared to 52, 52, 52, 59, 52% partial responders, respectively. A biosignature, defined by a significant decrease in any one of these five biomarkers, corresponded with satisfactory response to treatment in 97% patients at 2 month and 99% patients at 6 months of treatment. CONCLUSION: Change in inflammatory biomarkers correlates with treatment success. A five biomarker biosignature (MIG, IP-10, MIF, CCL22 and CCL23) could be used as an indicator of treatment success.


Asunto(s)
Biomarcadores/metabolismo , Interacciones Huésped-Patógeno , Tuberculosis/terapia , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Quimiocinas/sangre , Niño , Análisis Discriminante , Femenino , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Tuberculosis/sangre , Adulto Joven
4.
Med Res Rev ; 39(3): 1091-1136, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30506705

RESUMEN

Hepatitis C compromises the quality of life of more than 350 million individuals worldwide. Over the last decade, therapeutic regimens for treating hepatitis C virus (HCV) infections have undergone rapid advancements. Initially, structure-based drug design was used to develop molecules that inhibit viral enzymes. Subsequently, establishment of cell-based replicon systems enabled investigations into various stages of HCV life cycle including its entry, replication, translation, and assembly, as well as role of host proteins. Collectively, these approaches have facilitated identification of important molecules that are deemed essential for HCV life cycle. The expanded set of putative virus and host-encoded targets has brought us one step closer to developing robust strategies for efficacious, pangenotypic, and well-tolerated medicines against HCV. Herein, we provide an overview of the development of various classes of virus and host-directed therapies that are currently in use along with others that are undergoing clinical evaluation.


Asunto(s)
Antivirales/farmacología , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Animales , Antivirales/química , Antivirales/uso terapéutico , Genotipo , Hepacivirus/fisiología , Hepatitis C/tratamiento farmacológico , Humanos , Resultado del Tratamiento , Vacunas Virales/inmunología
5.
Microb Pathog ; 136: 103653, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31398527

RESUMEN

Pneumococcal strains are variably resistant to killing by neutrophil extracellular traps (NETs). We hypothesize that this variability in resistance is due to heterogeneity in pneumococcal surface protein A (PspA), a structurally diverse virulence factor of Streptococcus pneumoniae. Pneumococcal strains showed variability in induction of NETs and in susceptibility to killing by NETs. The variability in susceptibility to NETs-mediated killing of pneumococcal strains is attributed to PspA, as strains lacking the surface expression of PspA were significantly more sensitive to NETs-mediated killing compared to the wild-type strains. Using pspA switch mutants we were further able to demonstrate that NETs induction and killing by NETs is a function of PspA as mutants with switch PspA demonstrated donor phenotype. Antibody to PspA alone showed an increase in induction of NETs, and NETs thus generated were able to trap and kill pneumococci. Pneumococci opsonized with antibody to PspA showed increase adherence to NETs but a decrease susceptibility to killing by NETs. In conclusion we demonstrate a novel role for pneumococcal PspA in resisting NETs mediated killing and allowing the bacteria to escape containment by blocking binding of pneumococci to NETs.


Asunto(s)
Proteínas Bacterianas/metabolismo , Trampas Extracelulares/metabolismo , Evasión Inmune , Viabilidad Microbiana , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/fisiología , Células Cultivadas , Humanos
6.
Microb Pathog ; 99: 209-219, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27569531

RESUMEN

Pneumococcal surface protein A (PspA) is the only pneumococcal surface protein known to strongly bind lactoferrin on the bacterial surface. In the absence of PspA Streptococcus pneumoniae becomes more susceptible to killing by human apolactoferrin (apo-hLf), the iron-free form of lactoferrin. In the present study we examined diverse strains of S. pneumoniae that differed by 2 logs in their susceptibility to apo-hLf. Among these strains, the amount of apo-hLf that bound to cell surface PspA correlated directly with the resistance of the strain to killing by apo-hLf. Moreover examination of different pspA alleles on shared genetic backgrounds revealed that those PspAs that bound more lactoferrin conferred greater resistance to killing by apo-hLf. The effects of capsule on killing of pneumococci by apo-hLf were generally small, but on one genetic background, however, the lack of capsule was associated with 4-times as much apo-hLf binding and 30-times more resistance to killing by apo-hLf. Overall these finding strongly support the hypothesis that most of the variation in the ability of apo-hLf is dependent on the variation in the binding of apo-hLf to surface PspA and this binding is dependent on variation in PspA as well as variation in capsule which may enhance killing by reducing the binding of apo-hLf to PspA.


Asunto(s)
Alelos , Antibacterianos/metabolismo , Apoproteínas/metabolismo , Cápsulas Bacterianas/metabolismo , Proteínas Bacterianas/metabolismo , Lactoferrina/metabolismo , Viabilidad Microbiana/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Proteínas Bacterianas/genética , Variación Genética , Humanos , Unión Proteica , Streptococcus pneumoniae/genética
7.
J Immunol ; 192(4): 1718-31, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24453257

RESUMEN

Genital tract carriage of group B streptococcus (GBS) is prevalent among adult women; however, the dynamics of chronic GBS genital tract carriage, including how GBS persists in this immunologically active host niche long term, are not well defined. To our knowledge, in this study, we report the first animal model of chronic GBS genital tract colonization using female mice synchronized into estrus by delivery of 17ß-estradiol prior to intravaginal challenge with wild-type GBS 874391. Cervicovaginal swabs, which were used to measure bacterial persistence, showed that GBS colonized the vaginal mucosa of mice at high numbers (10(6)-10(7) CFU/swab) for at least 90 d. Cellular and histological analyses showed that chronic GBS colonization of the murine genital tract caused significant lymphocyte and PMN cell infiltrates, which were localized to the vaginal mucosal surface. Long-term colonization was independent of regular hormone cycling. Immunological analyses of 23 soluble proteins related to chemotaxis and inflammation showed that the host response to GBS in the genital tract comprised markers of innate immune activation including cytokines such as GM-CSF and TNF-α. A nonhemolytic isogenic mutant of GBS 874391, Δcyle9, was impaired for colonization and was associated with amplified local PMN responses. Induction of DNA neutrophil extracellular traps, which was observed in GBS-infected human PMNs in vitro in a hemolysin-dependent manner, appeared to be part of this response. Overall, this study defines key infection dynamics in a novel murine model of chronic GBS genital tract colonization and establishes previously unknown cellular and soluble defense responses to GBS in the female genital tract.


Asunto(s)
Proteínas Hemolisinas/metabolismo , Infecciones del Sistema Genital/inmunología , Streptococcus agalactiae/inmunología , Vagina/inmunología , Animales , Biomarcadores , Movimiento Celular/inmunología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Estradiol/metabolismo , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Neutrófilos/inmunología , Infecciones del Sistema Genital/microbiología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Vagina/microbiología
8.
J Immunol ; 189(11): 5327-35, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23105137

RESUMEN

In the presence of normal serum, complement component C3 is deposited on pneumococci primarily via the classical pathway. Pneumococcal surface protein A (PspA), a major virulence factor of pneumococci, effectively inhibits C3 deposition. PspA's C terminus has a choline-binding domain that anchors PspA to the phosphocholine (PC) moieties on the pneumococcal surface. C-reactive protein (CRP), another important host defense molecule, also binds to PC, and CRP binding to pneumococci enhances complement C3 deposition through the classical pathway. Using flow cytometry of PspA(+) and PspA(-) strains, we observed that the absence of PspA led to exposure of PC, enhanced the surface binding of CRP, and increased the deposition of C3. Moreover, when the PspA(-) mutant was incubated with a pneumococcal eluate containing native PspA, there was decreased deposition of CRP and C3 on the pneumococcal surface compared with incubation with an eluate from a PspA(-) strain. This inhibition was not observed when a recombinant PspA fragment, which lacks the choline-binding region of PspA, was added to the PspA(-) mutant. Also, there was much greater C3 deposition onto the PspA(-) pneumococcus when exposed to normal mouse serum from wild-type mice as compared with that from CRP knockout mice. Furthermore, when CRP knockout mouse serum was replenished with CRP, there was a dose-dependent increase in C3 deposition. The combined data reveal a novel mechanism of complement inhibition by a bacterial protein: inhibition of CRP surface binding and, thus, diminution of CRP-mediated complement deposition.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteína C-Reactiva/metabolismo , Complemento C3/metabolismo , Fosforilcolina/metabolismo , Streptococcus pneumoniae/metabolismo , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/farmacología , Unión Competitiva , Proteína C-Reactiva/antagonistas & inhibidores , Proteína C-Reactiva/inmunología , Complemento C3/antagonistas & inhibidores , Complemento C3/inmunología , Medios de Cultivo , Humanos , Ratones , Fosforilcolina/química , Fosforilcolina/inmunología , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/inmunología
9.
Microb Genom ; 10(1)2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38270581

RESUMEN

Pakistan is amongst the four countries with the highest number of pneumococcal deaths. While the PCV10 vaccine was introduced in Pakistan in October 2012, data regarding the impact of the vaccine on the population dynamics of Streptococcus pneumoniae in Pakistan remain obscure. Using whole genome sequencing of 190 isolates (nasopharyngeal carriage=75, disease=113, unknown sites=2) collected between 2002 and 2020, this study presents characteristics of pneumococcal strains in Pakistan in the pre- and post-vaccine era. The isolates were characterized on the basis of serotype distribution, genetic lineages (or Global Pneumococcal Sequence Cluster, GPSC) and antibiotic resistance. A high level of diversity in serotype and genetic lineages of pneumococci was observed in Pakistan. Among 190 isolates, we identified 54 serotypes, 67 GPSCs and 116 sequence types (STs) including 23 new STs. The most prevalent GPSCs and their associated serotypes in nasopharyngeal carriage were GPSC54 (expressing serotype 9V), GPSC5 (15A and 7B, and serogroup 24), GPSC25 (15B/15C), GPSC67 (18C) and GPSC376 (6A and 6D). Similarly, among 113 disease-causing isolates, the most prevalent GPSC/serotype combinations were GPSC2 (serotype 1), GPSC10 (serotypes 14, 10A, 19A and 19F), GPSC43 (serotypes 13, 11A, 23B, 35A and 9V), GPSC67 (serotypes 18A and 18C) and GPSC642 (serotype 11A). Of the 190 isolates, the highest levels of resistance were observed against penicillin (58.9 %, n=122), erythromycin (29.5 %, n=56), clindamycin (13.2 %, n=25), co-trimoxazole (94.2 %, n=179) and tetracycline/doxycycline (53.2 %, n=101). A higher proportion of disease-causing isolates were multidrug resistant as compared to carriage isolates (54 % vs 25 %). Our data suggest limited coverage of PCV10 in nasopharyngeal (21.6 %, 16/74) as well as disease-causing (38.1 %, 16/42) isolates among children ≤5 years old; however, higher valent vaccine PCV13 would increase the coverage rates to 33.8 % in nasopharyngeal and 54.8 % in disease-causing isolates, whereas PCV24/25 would offer the highest coverage rates. Owing to the diversity of serotypes observed during the post-vaccine period, the suggested inclusion of serotype in future vaccine formulations will require investigations with larger data sets with an extended temporal window. This article contains data hosted by Microreact.


Asunto(s)
Vacunas Neumococicas , Streptococcus pneumoniae , Niño , Humanos , Preescolar , Pakistán/epidemiología , Streptococcus pneumoniae/genética , Antibacterianos/farmacología
10.
Am J Trop Med Hyg ; 108(2): 278-284, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36623485

RESUMEN

Typhoid fever, caused by Salmonella enterica serovar Typhi (S. Typhi), is a life-threatening bacterial infection. Recently, an outbreak of a new sublineage of extensively drug resistant (XDR) S. Typhi emerged in Pakistan in the province of Sindh. This sublineage had both a composite multidrug resistance transposon integrated on the chromosome and an acquired IncY plasmid carrying the extended spectrum beta-lactamase, blaCTX-M-15, which conferred resistance to third-generation cephalosporins. We observed previously that XDR typhoid had spread beyond the originating southern Sindh Province. Thus, we sought to determine the genetic diversity of 58 ceftriaxone-resistant S. Typhi clinical isolates by whole genome sequencing collected across Pakistan from November 2018 to December 2020 to provide insights into the molecular epidemiology of the evolving outbreak. We identify multiple novel genomic integrations of the extended spectrum beta-lactamase gene into the chromosome in S. Typhi, revealing the existence of various XDR typhoid variants circulating in the country. Notably, the integration of the IncY plasmid bearing antibiotic resistance genes may allow for subsequent plasmid acquisition by these variants, potentially leading to further plasmid-borne multidrug resistance. Our results can inform containment initiatives, help track associated outcomes and international spread, and help determine how widespread the risk is.


Asunto(s)
Fiebre Tifoidea , Humanos , Fiebre Tifoidea/tratamiento farmacológico , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/microbiología , Pakistán/epidemiología , Salmonella typhi/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , beta-Lactamasas/genética
11.
Front Med (Lausanne) ; 10: 1076690, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36895726

RESUMEN

Type 2-diabetes, particularly poorly controlled diabetes, is a risk factor for several infections such as lower respiratory tract and skin infections. Hyperglycemia, a characteristic downstream effect of poorly controlled diabetes, has been shown to impair the function of immune cells, in particular neutrophils. Several studies have demonstrated that hyperglycemia-mediated priming of NADPH oxidase results in subsequent elevated levels of reactive oxygen species (ROS). In healthy neutrophils, ROS plays an important role in pathogen killing by phagocytosis and by induction of Neutrophil Extracellular Traps (NETs). Given the key role of ROS in autophagy, phagocytosis and NETosis, the relationship between these pathways and the role of diabetes in the modulation of these pathways has not been explored previously. Therefore, our study aimed to understand the relationship between autophagy, phagocytosis and NETosis in diabetes. We hypothesized that hyperglycemia-associated oxidative stress alters the balance between phagocytosis and NETosis by modulating autophagy. Using whole blood samples from individuals with and without type 2-diabetes (in the presence and absence of hyperglycemia), we demonstrated that (i) hyperglycemia results in elevated levels of ROS in neutrophils from those with diabetes, (ii) elevated levels of ROS increase LCIII (a marker for autophagy) and downstream NETosis. (iii) Diabetes was also found to be associated with low levels of phagocytosis and phagocytic killing of S. pneumoniae. (iv) Blocking either NADPH oxidase or cellular pathways upstream of autophagy led to a significant reduction in NETosis. This study is the first to demonstrate the role of ROS in altering NETosis and phagocytosis by modulating autophagy in type 2-diabetes. GRAPHICAL ABSTRACT.

12.
Clin Invest Med ; 35(4): E237-45, 2012 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-22863562

RESUMEN

PURPOSE: This study examined genetic associations of patatin-like phospholipase domain containing 3 gene (PNPLA3) polymorphisms and liver aminotransferases in an extensively documented, randomly recruited Mexican American population at high risk of liver disease. METHODS: Two single nucleotide polymorphisms (SNP) in the PNPLA3 gene (i.e., rs738409 and rs2281135) were genotyped in 1532 individuals. Population stratification was corrected by the genotyping of 103 ancestry informative markers (AIMs) for Mexican Americans. RESULTS: Both PNPLA3 SNPs showed highly significant association with alanine aminotransferase (ALT) levels, but was also, in males, associated with aspartate aminotransferase (AST) levels. Haplotypic association test of the two SNPs suggested stronger genetic association with rs738409 than rs2281135. Obvious sex effects were observed: rs738409-sex interaction in ALT levels P = 8.37 x 10(-4); rs738409-sex interaction in AST levels P = 5.03 x 10(-3). CONCLUSIONS: This population study highlights a sex-specific association of PNPLA3 polymorphisms and elevated liver enzymes in a population-based study, independent of common pathological factors of the metabolic syndrome. The strong genetic association found in women ≤ 50 years old, but not in women > 50 years old, suggests that sex hormones may mediate the sex effect.


Asunto(s)
Alanina Transaminasa/genética , Aspartato Aminotransferasas/metabolismo , Lipasa/genética , Hepatopatías/genética , Proteínas de la Membrana/genética , Polimorfismo de Nucleótido Simple , Caracteres Sexuales , Adulto , Factores de Edad , Alanina Transaminasa/metabolismo , Aspartato Aminotransferasas/genética , Femenino , Genotipo , Humanos , Lipasa/metabolismo , Hígado/metabolismo , Hepatopatías/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Síndrome Metabólico/genética , Síndrome Metabólico/metabolismo , Americanos Mexicanos , Persona de Mediana Edad
13.
Tuberculosis (Edinb) ; 136: 102251, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36081251

RESUMEN

Tuberculosis (TB) is a contagious disease that causes 1.5 million deaths per year globally. Early diagnosis of TB patients is critical to control its spread. However, standard TB diagnostic tests such as sputum culture take days to weeks to produce results. Here, we demonstrate a quick, portable, easy-to-use, and non-invasive optical sensor based on sputum samples for TB detection. The probe uses Raman spectroscopy to detect TB in a patient's sputum supernatant. We deploy a machine-learning algorithm, principal component analysis (PCA), on the acquired Raman data to enhance the detection sensitivity and specificity. On testing 112 potential TB patients, our results show that the developed probe's accuracy is 100% for true-positive and 93.4% for true-negative. Moreover, the probe correctly identifies patients on TB medication. We anticipate that our work will lead to a viable and rapid TB diagnostic platform.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Aprendizaje Automático , Sensibilidad y Especificidad , Espectrometría Raman , Esputo , Tuberculosis/diagnóstico
14.
Lancet Microbe ; 3(10): e735-e743, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35985351

RESUMEN

BACKGROUND: Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context. METHODS: Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster (GPSC) and a clonal complex (CC) were assigned to each genome. Phylogenetic, evolutionary, and spatiotemporal analysis were conducted using the same 24F collection and supplemented with a global collection of genomes belonging to the lineage of interest from the GPS project database (n=25 590). FINDINGS: Serotype 24F was identified in numerous countries mainly due to the clonal spread of three lineages: GPSC10 (CC230), GPSC16 (CC156), and GPSC206 (CC7701). GPSC10 was the only multidrug-resistant lineage. GPSC10 drove the increase in 24F in France and had high invasive disease potential. The international dataset of GPSC10 (n=888) revealed that this lineage expressed 16 other serotypes, with only six included in 13-valent PCV (PCV13). All serotype 24F isolates were clustered in a single clade within the GPSC10 phylogeny and long-range transmissions were detected from Europe to other continents. Spatiotemporal analysis showed GPSC10-24F took 3-5 years to spread across France and a rapid change of serotype composition from PCV13 serotype 19A to 24F during the introduction of PCV13 was observed in neighbouring country Spain. INTERPRETATION: Our work reveals that GPSC10 alone is a challenge for serotype-based vaccine strategy. More systematic investigation to identify lineages like GPSC10 will better inform and improve next-generation preventive strategies against pneumococcal diseases. FUNDING: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control and Prevention.


Asunto(s)
Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , Filogenia , Infecciones Neumocócicas/epidemiología , Serogrupo , Streptococcus pneumoniae/genética , Vacunas Conjugadas
15.
Infect Immun ; 79(6): 2440-50, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21422179

RESUMEN

It is known that apolactoferrin, the iron-free form of human lactoferrin, can kill many species of bacteria, including Streptococcus pneumoniae. Lactoferricin, an N-terminal peptide of apolactoferrin, and fragments of it are even more bactericidal than apolactoferrin. In this study we found that apolactoferrin must be cleaved by a serine protease in order for it to kill pneumococci. The serine protease inhibitors were able to block killing by apolactoferrin but did not block killing by a lactoferrin-derived peptide. Thus, the killing of pneumococci by apolactoferrin appears to require a protease to release a lactoferricin-like peptide(s). Incubation of apolactoferrin with growing pneumococci resulted in a 12-kDa reduction in its molecular mass, of which about 7 to 8 kDa of the reduction was protease dependent. Capsular type 2 and 19F strains with mutations in the gene encoding the major cell wall-associated serine protease, prtA, lost much of their ability to degrade apolactoferrin and were relatively resistant to killing by apolactoferrin (P < 0.001). Recombinant PrtA was also able to cleave apolactoferrin, reducing its mass by about 8 kDa, and greatly enhance the killing activity of the solution containing the apolactoferrin and its cleavage products. Mass spectroscopy revealed that PrtA makes a major cut between amino acids 78 and 79 of human lactoferrin, removing the N-terminal end of the molecule (about 8.6 kDa). The simplest interpretation of these data is that the mechanism by which apolactoferrin kills Streptococcus pneumoniae requires the release of a lactoferricin-like peptide(s) and that it is this peptide(s), and not the intact apolactoferrin, which kills pneumococci.


Asunto(s)
Apoproteínas/fisiología , Lactoferrina/fisiología , Infecciones Neumocócicas/microbiología , Serina Proteasas/fisiología , Streptococcus pneumoniae/enzimología , Western Blotting , Clonación Molecular , Interacciones Huésped-Patógeno , Humanos , Proteínas Recombinantes , Serina Proteasas/genética , Inhibidores de Serina Proteinasa/farmacología , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/fisiología , Espectrometría de Masas en Tándem
16.
Clin Invest Med ; 34(5): E290, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21968271

RESUMEN

OBJECTIVE: Adiponectin and leptin play critical roles in the development of Metabolic Syndrome (MetS). This study was designed to assess the feasibility of using circulating levels of adiponectin and leptin for the early diagnosis of MetS. METHODS: A cross-sectional study was performed using data from 367 participants randomly selected from a well-characterized cohort of Mexican-Americans living at the US-Mexico border. RESULTS: Significant differences in circulating levels of adiponectin and leptin were observed between males and females. Adiponectin/leptin correlated significantly with MetS in this population. A receiver-operator characteristic (ROC) analysis demonstrated that adiponectin/leptin showed a high sensitivity (70.9% for males, 78.9% for females) and specificity (90.2% for males and 69.8% for females) for the diagnosis of MetS, independent of BMI measurements. CONCLUSION: These data support the central role of adiponectin and leptin in MetS, and demonstrated that adiponectin/leptin can be used as a highly sensitive and specific biomarker for MetS.


Asunto(s)
Adiponectina/sangre , Leptina/sangre , Síndrome Metabólico/sangre , Adulto , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Americanos Mexicanos , Persona de Mediana Edad , Factores Sexuales
17.
PLoS One ; 16(4): e0250226, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33901205

RESUMEN

While antimicrobial resistance (AMR) continues to be a major public health problem in Pakistan, data regarding trends of resistance among pathogenic bacteria remains scarce, with few studies presenting long-term trends in AMR. This study was therefore designed to analyze long-term AMR trends at a national level in Pakistan. We report here results of a comprehensive analysis of resistance, among pathogens isolated from blood and cerebrospinal fluid (CSF), between 2011 and 2015. Susceptibility data was obtained from a local laboratory with collection points all across Pakistan (Chughtai Laboratory). Resistance proportions to most commonly used antimicrobials were calculated for each pathogen over a period of five years. While Acinetobacter species demonstrated highest resistance rates to all tested antimicrobials, a sharp increase in carbapenem resistance was the most noticeable (50%-95%) between 2011-2015. Our results also highlight the presence of third and fourth generation cephalosporins resistance in Salmonella enterica serovar Typhi in Pakistan. Interestingly, where rise in AMR was being observed in some major invasive pathogens, decreasing resistance trends were observed in Staphylococcus aureus, against commonly used antimicrobials. Overall pathogens isolated from blood and CSF between 2011-2015, showed an increase in resistance towards commonly used antimicrobials.


Asunto(s)
Cultivo de Sangre/tendencias , Líquido Cefalorraquídeo/microbiología , Farmacorresistencia Microbiana/fisiología , Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Estudios Transversales/métodos , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pakistán , Estudios Retrospectivos , Salmonella typhi/efectos de los fármacos , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Fiebre Tifoidea/microbiología
18.
Sci Rep ; 11(1): 2435, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33510184

RESUMEN

Sedentary life styles coupled with high-calorie diets and unhealthy social habits such as smoking, have put an ever-increasing number of people at risk of cardiovascular disorders (CVD), worldwide. A concomitant increase in the prevalence of type 2-diabetes (hyperglycemia), a risk factor for CVD, has further contributed towards escalating CVD-related mortalities. The increase in number of cases of type 2-diabetes underscores the importance of early diagnosis of cardiovascular disease in those with diabetes. In this work, we have evaluated the sensitivity and specificity of dyslipidemia and proinflammatory cytokines to be used as biomarkers for predicting the risk of CVD in those with diabetes. We hypothesize that interplay between dyslipidemia and diabetes-induced low-grade inflammation in those with type 2-diabetes increases the risk of CVD. A total of 215 participants were randomly recruited from the Cameron County Hispanic Cohort (CCHC). Of these, 99% were Mexican Americans living on Texas-Mexico border. Levels of cytokines, adipokines and lipid profile were measured. Cardiovascular disease (CVD) for this study was defined as prior diagnosis of heart attack, angina and stroke, while diabetes was defined by fasting blood glucose (FBG) of > 100 mg/dL and HbA1c of > 6.5, in accordance with American Diabetes Association (ADA) guidelines. Depending on type and distribution of data, various statistical tests were performed. Our results demonstrated higher rates of heart attack (14% vs 11.8%) and stroke (19.8% vs 10%) in those with diabetes as compared to non-diabetes. The odds of having a heart attack were eight times higher in the presence of elevated triglycerides and pro-inflammatory markers (TNFα and IL6) as compared to presence of pro-inflammatory markers only. The odds for heart attack among those with diabetes, increased by 20 fold in presence of high levels of triglycerides, TNFα, and IL6 when coupled with low levels of high-density lipid cholesterol (HDL-C). Lastly, our analysis showed that poorly controlled diabetes, characterized by HbA1c values of > 6.5 increases the odds of stroke by more than three fold. The study quantifies the role of lipid profile and pro-inflammatory markers in combination with standard risk factors towards predicting the risk of CVD in those with type 2-diabetes. The findings from the study can be directly translated for use in early diagnosis of heart disease and guiding interventions leading to a reduction in CVD-associated mortality in those with type 2-diabetes.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Citocinas/sangre , Diabetes Mellitus Tipo 2/sangre , Lípidos/sangre , Americanos Mexicanos , Biomarcadores/sangre , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/complicaciones , Prevalencia , Curva ROC , Riesgo , Medición de Riesgo , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicaciones
19.
Viruses ; 12(2)2020 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-32054060

RESUMEN

Microvirin (MVN) is one of the human immunodeficiency virus (HIV-1) entry inhibitor lectins, which consists of two structural domains sharing 35% sequence identity and contrary to many other antiviral lectins, it exists as a monomer. In this study, we engineered an MVN variant, LUMS1, consisting of two domains with 100% sequence identity, thereby reducing the chemical heterogeneity, which is a major factor in eliciting immunogenicity. We determined carbohydrate binding of LUMS1 through NMR chemical shift perturbation and tested its anti-HIV activity in single-round infectivity assay and its anti-hepatitis C virus (HCV) activity in three different assays including HCVcc, HCVpp, and replicon assays. We further investigated the effect of LUMS1 on the activation of T helper (Th) and B cells through flow cytometry. LUMS1 showed binding to (1-2)mannobiose, the minimum glycan epitope of MVN, potently inhibited HIV-1 and HCV with EC50 of 37.2 and 45.3 nM, respectively, and showed negligible cytotoxicity with CC50 > 10 µM against PBMCs, Huh-7.5 and HepG2 cells, and 4.9 µM against TZM-bl cells. LUMS1 did not activate Th cells, and its stimulatory effect on B cells was markedly less as compared to MVN. Together, with these effects, LUMS1 represents a potential candidate for the development of antiviral therapies.


Asunto(s)
Antivirales/farmacología , VIH-1/efectos de los fármacos , Hepacivirus/efectos de los fármacos , Lectinas/farmacología , Internalización del Virus/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Carbohidratos , Línea Celular , VIH-1/fisiología , Células Hep G2 , Hepacivirus/fisiología , Humanos , Lectinas/química , Lectinas/genética , Leucocitos Mononucleares/efectos de los fármacos , Unión Proteica , Células TH1/efectos de los fármacos , Células TH1/inmunología
20.
PLoS One ; 14(4): e0214435, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30943224

RESUMEN

BACKGROUND: Hepatitis C virus (HCV) infections are amongst the leading public health concerns in Pakistan with a high disease burden. Despite the availability of effective antiviral treatments in the country the disease burden in general population has not lowered. This could be attributed to the asymptomatic nature of this infection that results in lack of diagnosis until the late symptomatic stage. To better estimate and map HCV infections in the country a population-based analysis is necessary for an effective control of the infection. METHODS: Serologic samples of ~66,000 participants from all major cities of the Punjab province were tested for anti-HCV antibodies. The antibody-based seroprevalence was associated with socio-demographic variables including geographical region, age, gender and sex, and occupation. RESULTS: Overall serological response to HCV surface antigens was observed in over 17% of the population. Two of the districts were identified with significantly high prevalence in general population. Analysis by occupation showed significantly high prevalence in farmers (over 40%) followed by jobless and retired individuals, laborers and transporters. A significant difference in seroprevalence was observed in different age groups amongst sex and genders (male, female and transgender) with highest response in individuals of over 40 years of age. Moreover, most of the tested IDUs showed positive response for anti-HCV antibody. CONCLUSION: This study represents a retrospective analysis of HCV infections in general population of the most populated province of Pakistan to identify socio-demographic groups at higher risk. Two geographical regions, Faisalabad and Okara districts, and an occupational group, farmers, were identified with significantly high HCV seroprevalence. These socio-demographic groups are the potential focused groups for follow-up studies on factors contributing to the high HCV prevalence in these groups towards orchestrating effective prevention, control and treatment.


Asunto(s)
Anticuerpos contra la Hepatitis C/sangre , Antígenos de la Hepatitis C/sangre , Hepatitis C/epidemiología , Estudios Seroepidemiológicos , Adolescente , Adulto , Distribución por Edad , Anciano , Femenino , Hepacivirus/aislamiento & purificación , Hepacivirus/patogenicidad , Hepatitis C/sangre , Hepatitis C/virología , Humanos , Masculino , Persona de Mediana Edad , Pakistán/epidemiología , Distribución por Sexo , Adulto Joven
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