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1.
J Infect Dis ; 229(Supplement_2): S249-S254, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37995310

RESUMEN

The Los Angeles County Department of Public Health established a surveillance system to identify complicated (advanced human immunodeficiency virus [HIV] or hospitalized) mpox cases. From 1 August to 30 November 2022, we identified 1581 mpox cases, of which 134 (8.5%) were complicated. A subset of 8 cases did not recover after either initiating or completing a course of oral tecovirimat. All 8 patients were HIV positive and had advanced HIV (CD4 count <200 cells/µL). We identified 8 distinct mutations previously associated with tecovirimat resistance in specimens collected from 6 patients. Ongoing surveillance of viral evolution requires close coordination between health departments and frontline providers.


Asunto(s)
Seropositividad para VIH , Mpox , Humanos , Los Angeles , Benzamidas , Isoindoles
2.
MMWR Morb Mortal Wkly Rep ; 73(24): 546-550, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900699

RESUMEN

Tecovirimat is the first-line antiviral treatment recommended for severe mpox or for persons with mpox who are at risk for severe disease; tecovirimat is available in the United States under an expanded access investigational new drug (IND) protocol. During the 2022-2023 mpox outbreak, local U.S. health jurisdictions facilitated access to tecovirimat. In June 2022, Los Angeles County (LAC) rapidly developed strategies for tecovirimat distribution using existing medical countermeasure distribution networks established by the Public Health Emergency Preparedness Program and the Hospital Preparedness Program, creating a hub and spoke distribution network consisting of 44 hub facilities serving 456 satellite sites across LAC. IND patient intake forms were analyzed to describe mpox patients treated with tecovirimat. Tecovirimat treatment data were matched with case surveillance data to calculate time from specimen collection to patients receiving tecovirimat. Among 2,281 patients with mpox in LAC, 735 (32%) received tecovirimat during June 2022-January 2023. Among treated patients, approximately two thirds (508; 69%) received treatment through community clinics and pharmacies. The median interval from specimen collection to treatment was 2 days (IQR = 0-5 days). Local data collection and analysis helped to minimize gaps in treatment access and facilitated network performance monitoring. During public health emergencies, medical countermeasures can be rapidly deployed across a large jurisdiction using existing distribution networks, including clinics and pharmacies.


Asunto(s)
Antivirales , Brotes de Enfermedades , Mpox , Humanos , Brotes de Enfermedades/prevención & control , Los Angeles/epidemiología , Persona de Mediana Edad , Adulto , Adolescente , Femenino , Masculino , Adulto Joven , Anciano , Antivirales/uso terapéutico , Niño , Mpox/epidemiología , Preescolar , Lactante , Pirrolidinas , Benzamidas/uso terapéutico , Anciano de 80 o más Años , Ftalimidas
4.
Indian J Med Res ; 151(5): 419-423, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32611913

RESUMEN

Conducting population-based serosurveillance for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) will estimate and monitor the trend of infection in the adult general population, determine the socio-demographic risk factors and delineate the geographical spread of the infection. For this purpose, a serial cross-sectional survey would be conducted with a sample size of 24,000 distributed equally across four strata of districts categorized on the basis of the incidence of reported cases of COVID-19. Sixty districts will be included in the survey. Simultaneously, the survey will be done in 10 high-burden hotspot cities. ELISA-based antibody tests would be used. Data collection will be done using a mobile-based application. Prevalence from the group of districts in each of the four strata will be pooled to estimate the population prevalence of COVID-19 infection, and similarly for the hotspot cities, after adjusting for demographic characteristics and antibody test performance. The total number of reported cases in the districts and hotspot cities will be adjusted using this seroprevalence to estimate the expected number of infected individuals in the area. Such serosurveys repeated at regular intervals can also guide containment measures in respective areas. State-specific context of disease burden, priorities and resources should guide the use of multifarious surveillance options for the current COVID-19 epidemic.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Vigilancia de la Población/métodos , COVID-19 , Infecciones por Coronavirus/sangre , Estudios Transversales , Femenino , Humanos , India/epidemiología , Masculino , Pandemias , Neumonía Viral/sangre , Prevalencia , Proyectos de Investigación , SARS-CoV-2 , Estudios Seroepidemiológicos
5.
Indian J Med Res ; 152(1 & 2): 48-60, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32952144

RESUMEN

BACKGROUND & OBJECTIVES: Population-based seroepidemiological studies measure the extent of SARS-CoV-2 infection in a country. We report the findings of the first round of a national serosurvey, conducted to estimate the seroprevalence of SARS-CoV-2 infection among adult population of India. METHODS: From May 11 to June 4, 2020, a randomly sampled, community-based survey was conducted in 700 villages/wards, selected from the 70 districts of the 21 States of India, categorized into four strata based on the incidence of reported COVID-19 cases. Four hundred adults per district were enrolled from 10 clusters with one adult per household. Serum samples were tested for IgG antibodies using COVID Kavach ELISA kit. All positive serum samples were re-tested using Euroimmun SARS-CoV-2 ELISA. Adjusting for survey design and serial test performance, weighted seroprevalence, number of infections, infection to case ratio (ICR) and infection fatality ratio (IFR) were calculated. Logistic regression was used to determine the factors associated with IgG positivity. RESULTS: Total of 30,283 households were visited and 28,000 individuals were enrolled. Population-weighted seroprevalence after adjusting for test performance was 0.73 per cent [95% confidence interval (CI): 0.34-1.13]. Males, living in urban slums and occupation with high risk of exposure to potentially infected persons were associated with seropositivity. A cumulative 6,468,388 adult infections (95% CI: 3,829,029-11,199,423) were estimated in India by the early May. The overall ICR was between 81.6 (95% CI: 48.3-141.4) and 130.1 (95% CI: 77.0-225.2) with May 11 and May 3, 2020 as plausible reference points for reported cases. The IFR in the surveyed districts from high stratum, where death reporting was more robust, was 11.72 (95% CI: 7.21-19.19) to 15.04 (9.26-24.62) per 10,000 adults, using May 24 and June 1, 2020 as plausible reference points for reported deaths. INTERPRETATION & CONCLUSIONS: Seroprevalence of SARS-CoV-2 was low among the adult population in India around the beginning of May 2020. Further national and local serosurveys are recommended to better inform the public health strategy for containment and mitigation of the epidemic in various parts of the country.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/genética , Infecciones por Coronavirus/epidemiología , Inmunoglobulina G/sangre , Neumonía Viral/epidemiología , Adolescente , Adulto , Anciano , Betacoronavirus/patogenicidad , COVID-19 , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/virología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/virología , SARS-CoV-2 , Estudios Seroepidemiológicos , Adulto Joven
7.
J Biol Chem ; 290(34): 21032-21041, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26160173

RESUMEN

F-type ATP synthases are rotary nanomotor enzymes involved in cellular energy metabolism in eukaryotes and eubacteria. The ATP synthase from Gram-positive and -negative model bacteria can be autoinhibited by the C-terminal domain of its ϵ subunit (ϵCTD), but the importance of ϵ inhibition in vivo is unclear. Functional rotation is thought to be blocked by insertion of the latter half of the ϵCTD into the central cavity of the catalytic complex (F1). In the inhibited state of the Escherichia coli enzyme, the final segment of ϵCTD is deeply buried but has few specific interactions with other subunits. This region of the ϵCTD is variable or absent in other bacteria that exhibit strong ϵ-inhibition in vitro. Here, genetically deleting the last five residues of the ϵCTD (ϵΔ5) caused a greater defect in respiratory growth than did the complete absence of the ϵCTD. Isolated membranes with ϵΔ5 generated proton-motive force by respiration as effectively as with wild-type ϵ but showed a nearly 3-fold decrease in ATP synthesis rate. In contrast, the ϵΔ5 truncation did not change the intrinsic rate of ATP hydrolysis with membranes. Further, the ϵΔ5 subunit retained high affinity for isolated F1 but reduced the maximal inhibition of F1-ATPase by ϵ from >90% to ∼20%. The results suggest that the ϵCTD has distinct regulatory interactions with F1 when rotary catalysis operates in opposite directions for the hydrolysis or synthesis of ATP.


Asunto(s)
Adenosina Trifosfato/metabolismo , Secuencia de Bases , Proteínas de Escherichia coli/química , Escherichia coli/genética , Proteínas/química , Protones , Eliminación de Secuencia , Adenosina Trifosfato/química , Biocatálisis , Membrana Celular/química , Membrana Celular/metabolismo , Escherichia coli/enzimología , Escherichia coli/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expresión Génica , Hidrólisis , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Proteínas/genética , Proteínas/metabolismo , Fuerza Protón-Motriz , Termodinámica , Proteína Inhibidora ATPasa
8.
J Biol Chem ; 288(13): 9383-95, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23400782

RESUMEN

F1-ATPase is the catalytic complex of rotary nanomotor ATP synthases. Bacterial ATP synthases can be autoinhibited by the C-terminal domain of subunit ε, which partially inserts into the enzyme's central rotor cavity to block functional subunit rotation. Using a kinetic, optical assay of F1·Îµ binding and dissociation, we show that formation of the extended, inhibitory conformation of ε (εX) initiates after ATP hydrolysis at the catalytic dwell step. Prehydrolysis conditions prevent formation of the εX state, and post-hydrolysis conditions stabilize it. We also show that ε inhibition and ADP inhibition are distinct, competing processes that can follow the catalytic dwell. We show that the N-terminal domain of ε is responsible for initial binding to F1 and provides most of the binding energy. Without the C-terminal domain, partial inhibition by the ε N-terminal domain is due to enhanced ADP inhibition. The rapid effects of catalytic site ligands on conformational changes of F1-bound ε suggest dynamic conformational and rotational mobility in F1 that is paused near the catalytic dwell position.


Asunto(s)
Adenosina Difosfato/química , Adenosina Trifosfato/química , Escherichia coli/metabolismo , ATPasas de Translocación de Protón/química , Antibacterianos/farmacología , Transporte Biológico , Reactivos de Enlaces Cruzados/farmacología , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Hidrólisis , Cinética , Ligandos , Modelos Moleculares , Conformación Molecular , Plásmidos/metabolismo , Conformación Proteica , Estructura Terciaria de Proteína , ATPasas de Translocación de Protón/metabolismo , Factores de Tiempo
9.
Malar J ; 13: 284, 2014 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-25052385

RESUMEN

BACKGROUND: Anti-malarial drug resistance in Plasmodium falciparum in India has historically travelled from northeast India along the Myanmar border. The treatment policy for P. falciparum in the region was, therefore, changed from chloroquine to artesunate (AS) plus sulphadoxine-pyrimethamine (SP) in selected areas in 2005 and in 2008 it became the first-line treatment. Recognizing that resistance to the partner drug can limit the useful life of this combination therapy, routine in vivo and molecular monitoring of anti-malarial drug efficacy through sentinel sites was initiated in 2009. METHODS: Between May and October 2012, 190 subjects with acute uncomplicated falciparum malaria were enrolled in therapeutic efficacy studies in the states of Arunachal Pradesh, Tripura, and Mizoram. Clinical and parasitological assessments were conducted over 42 days of follow-up. Multivariate analysis was used to determine risk factors associated with treatment failure. Genotyping was done to distinguish re-infection from recrudescence as well as to determine the prevalence of molecular markers of antifolate resistance among isolates. RESULTS: A total of 169 patients completed 42 days of follow-up at three sites. The crude and PCR-corrected Kaplan-Meier survival estimates of AS + SP were 60.8% (95% CI: 48.0-71.4) and 76.6% (95% CI: 64.1-85.2) in Gomati, Tripura; 74.6% (95% CI: 62.0-83.6) and 81.7% (95% CI: 69.4-89.5) in Lunglei, Mizoram; and, 59.5% (95% CI: 42.0-73.2) and 82.3% (95% CI: 64.6-91.6) in Changlang, Arunachal Pradesh. Most patients with P. falciparum cleared parasitaemia within 24 hours of treatment, but eight, including three patients who failed treatment, remained parasitaemic on day 3. Risk factors associated with treatment failure included age < five years, fever at the time of enrolment and AS under dosing. No adverse events were reported. Presence of dhfr plus dhps quintuple mutation was observed predominantly in treatment failure samples. CONCLUSION: AS + SP treatment failure was widespread in northeast India and exceeded the threshold for changing drug policy. Based on these results, in January 2013 the expert committee of the National Vector Borne Disease Control Programme formulated the first subnational drug policy for India and selected artemether plus lumefantrine as the new first-line treatment in the northeast. Continued monitoring of anti-malarial drug efficacy is essential for effective malaria control.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Plasmodium falciparum/efectos de los fármacos , Pirimetamina , Sulfadoxina , Adolescente , Adulto , Antimaláricos/administración & dosificación , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/farmacología , Artemisininas/uso terapéutico , Artesunato , Niño , Preescolar , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Humanos , India/epidemiología , Estimación de Kaplan-Meier , Malaria Falciparum/mortalidad , Masculino , Pirimetamina/administración & dosificación , Pirimetamina/farmacología , Pirimetamina/uso terapéutico , Factores de Riesgo , Sulfadoxina/administración & dosificación , Sulfadoxina/farmacología , Sulfadoxina/uso terapéutico , Insuficiencia del Tratamiento
10.
Indian J Med Res ; 139(2): 205-15, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24718394

RESUMEN

The use of antimalarial drugs in India has evolved since the introduction of quinine in the 17 th century. Since the formal establishment of a malaria control programme in 1953, shortly after independence, treatments provided by the public sector ranged from chloroquine, the mainstay drug for many decades, to the newer, recently introduced artemisinin based combination therapy. The complexity of considerations in antimalarial treatment led to the formulation of a National Antimalarial Drug Policy to guide procurement as well as communicate best practices to both public and private healthcare providers. Challenges addressed in the policy include the use of presumptive treatment, the introduction of alternate treatments for drug-resistant malaria, the duration of primaquine therapy to prevent relapses of vivax malaria, the treatment of malaria in pregnancy, and the choice of drugs for chemoprophylaxis. While data on antimalarial drug resistance and both public and private sector treatment practices have been recently reviewed, the policy process of setting national standards has not. In this perspective on antimalarial drug policy, this review highlights its relevant history, analyzes the current policy, and examines future directions.


Asunto(s)
Antimaláricos/uso terapéutico , Resistencia a Medicamentos/genética , Malaria/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Artemisininas/efectos adversos , Artemisininas/uso terapéutico , Cloroquina/uso terapéutico , Humanos , India , Malaria/genética , Malaria/parasitología , Plasmodium falciparum/genética , Plasmodium falciparum/parasitología
11.
Glycobiology ; 23(11): 1270-80, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23964097

RESUMEN

Hyaluronan (HA) is widely detected in biological samples and its concentration is most commonly determined by the use of a labeled specific HA binding protein (aggrecan G1-IGD-G2, HABP), employing membrane blotting and sandwich enzyme-linked immunosorbent assay (ELISA)-like methods. However, the detected signal intensity or the quantified value obtained by using these surface-based methods is related to the molecular mass (M) of HA, especially for HA in the low M range below ~150 kDa. At the same mass or mass concentration, higher M HA gives a higher signal than lower M HA. We have experimentally determined the quantitative relationship between the M of HA (in the range 20-150 kDa) and the relative signal intensity in comparison with a standard HA, in a sandwich ELISA-like assay. An M-dependent signal correction factor (SCF) was calculated and used to correct the signal intensity, so that the corrected concentration value would more accurately reflect the true HA concentration in solution. The SCF for polydisperse low M HA was also calculated and compared with experimental results. When the molecular mass distribution of an HA sample is determined by a method such as gel electrophoresis, then its appropriately averaged SCF can be calculated and used to correct the signal in sandwich ELISA to obtain a more accurate concentration estimation. The correction method works for HA with M between ~150 and 20 kDa, but lower M HA is too poorly detected for useful analysis. The physical basis of the M-dependent detection is proposed to be the increase in detector-accessible fraction of each surface-bound molecule as M increases.


Asunto(s)
Receptores de Hialuranos/química , Ácido Hialurónico/química , Biotinilación , Densitometría , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Humanos , Immunoblotting , Peso Molecular
12.
Antimicrob Agents Chemother ; 57(7): 2948-54, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23587943

RESUMEN

Artemisinin combination therapies eliminate immature Plasmodium falciparum gametocytes but not mature gametocytes, which may persist for up to 1 month posttreatment. A single dose of primaquine, which is inexpensive and effective against mature gametocytes, could be added to further reduce the potential for posttreatment parasite transmission. Currently, we have few data regarding the effectiveness or safety of doing so. We collected data from 21 therapeutic efficacy trials of the National Antimalarial Drug Resistance Monitoring System of India conducted during 2009 to 2010, wherein 9 sites used single-dose primaquine (0.75 mg/kg of body weight) administered on day 2 along with artesunate plus sulfadoxine-pyrimethamine (AS+SP) while 12 did not. We estimated the effect of primaquine on posttreatment gametocyte clearance and the total number of gametocyte-weeks as determined by microscopy. We compared the median area under the curve for gametocyte density and reported adverse events. One thousand three hundred thirty-five patients completed the antimalarial drug treatment. Adjusting for region, primaquine increased the rate of gametocyte clearance (hazard ratio, 1.9; 95% confidence interval [CI], 1.1 to 3.3), prevented 45% (95% CI, 19 to 62) of posttreatment gametocyte-weeks, and decreased the area under the gametocyte density curve over the 28-day follow-up compared to AS+SP alone (P value = 0.01). The results were robust to other adjustment sets, and the estimated effect of primaquine increased during sensitivity analysis on the measurement of exposure time. No serious adverse events were detected. In conclusion, the addition of primaquine to AS+SP was effective in reducing the posttreatment presence of P. falciparum gametocytes. Primaquine was well tolerated and could be administered along with an artemisinin combination therapy as the first-line therapy.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Primaquina/uso terapéutico , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Adolescente , Adulto , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Artemisininas/administración & dosificación , Artemisininas/efectos adversos , Niño , Preescolar , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Humanos , India , Lactante , Recién Nacido , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/transmisión , Masculino , Persona de Mediana Edad , Parasitemia/tratamiento farmacológico , Parasitemia/epidemiología , Parasitemia/prevención & control , Primaquina/administración & dosificación , Primaquina/efectos adversos , Pirimetamina/administración & dosificación , Pirimetamina/efectos adversos , Prevención Secundaria , Sulfadoxina/administración & dosificación , Sulfadoxina/efectos adversos , Adulto Joven
13.
Trop Med Int Health ; 18(7): 800-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23627694

RESUMEN

OBJECTIVE: To characterise the epidemiology of Plasmodium falciparum gametocytemia and determine the prevalence, age structure and the viability of a predictive model for detection. METHODS: We collected data from 21 therapeutic efficacy trials conducted in India during 2009-2010 and estimated the contribution of each age group to the reservoir of transmission. We built a predictive model for gametocytemia and calculated the diagnostic utility of different score cut-offs from our risk score. RESULTS: Gametocytemia was present in 18% (248/1 335) of patients and decreased with age. Adults constituted 43%, school-age children 45% and under fives 12% of the reservoir for potential transmission. Our model retained age, sex, region and previous antimalarial drug intake as predictors of gametocytemia. The area under the receiver operator characteristic curve was 0.76 (95%CI:0.73,0.78), and a cut-off of 14 or more on a risk score ranging from 0 to 46 provided 91% (95%CI:88,95) sensitivity and 33% (95%CI:31,36) specificity for detecting gametocytemia. CONCLUSIONS: Gametocytemia was common in India and varied by region. Notably, adults contributed substantially to the reservoir for potential transmission. Predictive modelling to generate a clinical algorithm for detecting gametocytemia did not provide sufficient discrimination for targeting interventions.


Asunto(s)
Malaria Falciparum/parasitología , Tamizaje Masivo/métodos , Parasitemia , Plasmodium falciparum/patogenicidad , Adolescente , Factores de Edad , Antimaláricos/uso terapéutico , Área Bajo la Curva , Niño , Preescolar , Femenino , Humanos , India/epidemiología , Malaria Falciparum/epidemiología , Malaria Falciparum/transmisión , Masculino , Modelos Biológicos , Parasitemia/diagnóstico , Parasitemia/epidemiología , Parasitemia/parasitología , Prevalencia , Curva ROC , Factores de Riesgo , Factores Sexuales
14.
Malar J ; 12: 247, 2013 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-23866298

RESUMEN

BACKGROUND: Artesunate + sulphadoxine-pyrimethamine (AS + SP) is recommended throughout India as the first-line treatment for uncomplicated falciparum malaria. Due to the presence of several eco-epidemiological zones of malaria and variable drug pressure, it is necessary to evaluate the efficacy of this combination in different regions of India. The objective of this study was to use clinical and molecular methods to monitor the efficacy of AS + SP in three diverse sites. METHODS: The study was undertaken in three high endemic sites of central and eastern India. Patients with uncomplicated falciparum malaria were enrolled and followed for 28 days. Molecular genotyping was conducted for merozoite surface protein (msp1 and msp2) to differentiate between re-infection and recrudescence and for the dhfr and dhps genes to monitor antifolate drug resistance. RESULTS: In all, 149 patients were enrolled at the three sites. The crude cure rates were 95.9%, 100%, and 100% in Ranchi, Keonjhar, and West Garo Hills respectively. PCR-corrected cure rates were 100% at all sites. In dhfr, 27% of isolates had triple mutations, while 46% isolates were double-mutants. The most prevalent mutation was S108N followed by C59R. 164 L mutation was observed in 43/126 (34%) isolates. In dhps, most (76%) of the isolates were wild-type. Only 2.5% (2/80) isolates showed double mutation. dhfr-dhps two locus mutation were observed in 16% (13/80) isolates. Parasite clearance time was not related with antifolate mutations. CONCLUSIONS: AS + SP combination therapy remained effective against falciparum malaria despite common mutations promoting resistance to antifolate drugs. Although the prevalence of double and triple mutations in dhfr was high, the prevalence of dhfr-dhps two locus mutations were low. Even isolates with dhfr triple and dhfr-dhps two locus mutations achieved adequate clinical and parasitological response.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/genética , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Adolescente , Artesunato , Niño , Preescolar , Dihidropteroato Sintasa/genética , Combinación de Medicamentos , Resistencia a Medicamentos/genética , Enfermedades Endémicas , Femenino , Humanos , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Masculino , Plasmodium falciparum/efectos de los fármacos , Mutación Puntual , Prevalencia , Estudios Prospectivos , Proteínas Protozoarias/genética , Tetrahidrofolato Deshidrogenasa/genética , Resultado del Tratamiento
15.
Clin Case Rep ; 11(6): e7511, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37334338

RESUMEN

Key Clinical Message: A 26-year-old male patient admitted to the hospital ward with experience of repetitive syncopes for a year. The patient was diagnosed with sick sinus syndrome. The aim of this clinical report is to highlight the variability of anatomical findings associated with polysplenia pattern. Abstract: This case report presents a 26-year-old male patient who presented to the medical ward with a complaint of repeating blackouts for a year. The patient was then diagnosed with sick sinus syndrome, and further investigations revealed left isomerism, polysplenia, and no congenital heart defects. Holter monitoring, ultrasonography, electrocardiography, and computed tomography were used to confirm the diagnosis. The patient underwent DDDR pacemaker implantation for the treatment of SA node dysfunction. The report highlights the variability of anatomical findings associated with polysplenia pattern and the various types of heartbeat disruptions that may occur in the atrial appendages of the left side isomerism.

16.
PLoS Pathog ; 6(3): e1000830, 2010 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-20360965

RESUMEN

The Thailand-Cambodia border is the epicenter for drug-resistant falciparum malaria. Previous studies have shown that chloroquine (CQ) and pyrimethamine resistance originated in this region and eventually spread to other Asian countries and Africa. However, there is a dearth in understanding the origin and evolution of dhps alleles associated with sulfadoxine resistance. The present study was designed to reveal the origin(s) of sulfadoxine resistance in Cambodia and its evolutionary relationship to African and South American dhps alleles. We sequenced 234 Cambodian Plasmodium falciparum isolates for the dhps codons S436A/F, A437G, K540E, A581G and A613S/T implicated in sulfadoxine resistance. We also genotyped 10 microsatellite loci around dhps to determine the genetic backgrounds of various alleles and compared them with the backgrounds of alleles prevalent in Africa and South America. In addition to previously known highly-resistant triple mutant dhps alleles SGEGA and AGEAA (codons 436, 437, 540, 581, 613 are sequentially indicated), a large proportion of the isolates (19.3%) contained a 540N mutation in association with 437G/581G yielding a previously unreported triple mutant allele, SGNGA. Microsatellite data strongly suggest the strength of selection was greater on triple mutant dhps alleles followed by the double and single mutants. We provide evidence for at least three independent origins for the double mutants, one each for the SGKGA, AGKAA and SGEAA alleles. Our data suggest that the triple mutant allele SGEGA and the novel allele SGNGA have common origin on the SGKGA background, whereas the AGEAA triple mutant was derived from AGKAA on multiple, albeit limited, genetic backgrounds. The SGEAA did not share haplotypes with any of the triple mutants. Comparative analysis of the microsatellite haplotypes flanking dhps alleles from Cambodia, Kenya, Cameroon and Venezuela revealed an independent origin of sulfadoxine resistant alleles in each of these regions.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Sulfadoxina/uso terapéutico , África , Cambodia , Codón/genética , Resistencia a Medicamentos/genética , Evolución Molecular , Genes Protozoarios , Variación Genética , Haplotipos , Humanos , Desequilibrio de Ligamiento , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Repeticiones de Microsatélite , Prevalencia , América del Sur
17.
Bull World Health Organ ; 90(12): 895-904, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23284195

RESUMEN

OBJECTIVE: To describe India's National Antimalarial Drug Resistance Monitoring System, measure the efficacy of first-line malaria treatments, and determine risk factors for treatment failure. METHODS: In 2009-2010, prospective studies with 28 days of follow-up were conducted at 25 sentinel sites. Patients infected with Plasmodium falciparum were given artesunate plus sulfadoxine-pyrimethamine (AS+SP); those infected with P. vivax were given chloroquine. Polymerase chain reaction was used to distinguish post-treatment reinfection from treatment failure. Isolates of P. falciparum were checked for dhfr and dhps mutations. FINDINGS: Overall, 1664 patients were enrolled. Kaplan-Meier survival analysis showed an efficacy of 98.8% for AS+SP. Most patients with P. falciparum parasitaemia cleared their parasitaemias within 24 hours of treatment initiation, but six, including four with treatment failure, remained parasitaemic after 72 hours. Double mutants in dhfr were found in 68.4% of the genotyped isolates. Triple or quadruple mutants in dhfr and mutations in dhps were rare. A daily dose of artesunate of < 3 mg per kg of body weight, age of less than 5 years, and fever at enrolment were associated with an increased risk of treatment failure. Chloroquine remained 100% efficacious and generally cleared P. vivax parasitaemias within 48 hours. Vomiting (seen in 47 patients) was the most common adverse event. CONCLUSION: India's National Antimalarial Drug Resistance Monitoring System provides wide coverage. The first-line antimalarials used in the country remain safe and efficacious. The treatment of malaria in young children and the relative benefits of age- and weight-based dosing need further exploration.


Asunto(s)
Antimaláricos/uso terapéutico , Farmacorresistencia Microbiana/genética , Malaria Falciparum/tratamiento farmacológico , Malaria Vivax/tratamiento farmacológico , Antimaláricos/farmacología , Artemisininas/farmacología , Artemisininas/uso terapéutico , Cloroquina/farmacología , Cloroquina/uso terapéutico , Humanos , India/epidemiología , Estimación de Kaplan-Meier , Pirimetamina/farmacología , Pirimetamina/uso terapéutico , Factores de Riesgo , Sulfadoxina/farmacología , Sulfadoxina/uso terapéutico , Resultado del Tratamiento
18.
J Vector Borne Dis ; 49(3): 157-63, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23135010

RESUMEN

BACKGROUND & OBJECTIVES: The proportion of malaria cases that are complicated and fatal are not well described in India. Alipurduar sub-division of Jalpaiguri district in West Bengal is highly endemic for malaria. We constructed a retrospective cohort of severe malaria patients admitted in the secondary and tertiary care facilities in Alipurduar to determine the incidence, assess the management, and evaluate the reporting of severe and fatal malaria. METHODS: We reviewed routine surveillance data and the case records of all the malaria patients admitted in all secondary and tertiary care facilities, both public and private. We defined severe malaria cases as Plasmodium falciparum infection with clinical signs and symptoms of organ involvement in a resident of Alipurduar admitted during January to December 2009. We compared clinical and demographic characteristics of severe malaria cases that died with those who survived. We also reviewed human resources and laboratory facilities available for the treatment of severe malaria in these health facilities. RESULTS: During 2009, 6191 cases of P. falciparum in Alipurduar were reported to the malaria surveillance system. We identified 336 (5.4%) cases of severe malaria among which 33 (9.8%) patients died. Four malaria deaths were also recorded from primary health centres. Only 17 of the 37 (46%) total deaths recorded were reported to the routine surveillance system. Most severe cases were males (65%), aged >15 years (72%), and nearly half were admitted to secondary care hospitals (48%). In multivariate analysis, the risk factors associated with death included increased delay fever onset and hospitalization, treatment in a secondary level hospital, younger age, and multi-organ involvement. The secondary level public hospital had too few physicians and nurses for supporting severe malaria patients as well as inadequate laboratory facilities for monitoring such patients. CONCLUSIONS: Severe and fatal malaria continue to burden Alipurduar and record keeping in health facilities was poor. Many malaria deaths were not routinely reported even in the public sector. Improved surveillance and increased human and laboratory resources are needed to reduce malaria mortality.


Asunto(s)
Notificación de Enfermedades/estadística & datos numéricos , Malaria Falciparum/epidemiología , Centros de Atención Secundaria/estadística & datos numéricos , Centros de Atención Terciaria/estadística & datos numéricos , Adolescente , Adulto , Niño , Preescolar , Femenino , Hospitalización , Humanos , Incidencia , India/epidemiología , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , Estaciones del Año , Factores de Tiempo , Adulto Joven
19.
Neurol India ; 70(5): 1971-1975, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36352596

RESUMEN

Background: Cerebral venous thrombosis (CVT) is an uncommon cause of stroke and shares common risk factors with arterial strokes such as hyperhomocysteinemia, tobacco, alcohol, drugs, and hypercoagulable state. These risk factors can alter both arterial and venous health leading to the occurrence of atherosclerosis in CVT patients. Aims: To evaluate carotid hemodynamics in CVT patients. Settings and Design: Prospective hospital-based case-control study. Methods: This study included 50 consecutive CVT patients and 50 healthy controls. The demographic data, vascular risk factors, clinical data, biochemical, and radiological parameters were recorded. Carotid sonography was performed in CVT patients within the first 24 h of admission. Statistical Analysis: MedCalc 17. Results: The age of the patients was 35.04 ± 9.48 years and the controls 38.88 ± 10.41 years with male preponderance in both groups. Risk factors for atherosclerosis among patients included hyperhomocysteinemia (40 patients), diabetes mellitus (4 patients), hypertension (9 patients), alcohol (17 patients), and tobacco (21 patients). Eight patients had abnormal carotid sonography. Six had nonflow-limiting plaques, one had carotid occlusion, two had increased intimal-medial thickness, and one had increased peak systolic velocity. Among the controls, three subjects had nonflow-limiting plaques. There was no difference in carotid hemodynamic parameters between controls and patients; and those with normal and elevated homocysteine. Conclusion: This is the first study to our knowledge looking at carotid health in venous strokes. The relative risk for carotid atherosclerosis in CVT patients is higher and requires long-term follow-up for the initiation of preventive measures.


Asunto(s)
Aterosclerosis , Hiperhomocisteinemia , Trombosis Intracraneal , Accidente Cerebrovascular , Trombosis de la Vena , Humanos , Masculino , Adulto , Estudios de Casos y Controles , Estudios Prospectivos , Trombosis de la Vena/complicaciones , Trombosis de la Vena/diagnóstico por imagen , Factores de Riesgo
20.
Nat Commun ; 13(1): 3439, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35715406

RESUMEN

The sperm calcium channel CatSper plays a central role in successful fertilization as a primary Ca2+ gateway. Here, we applied cryo-electron tomography to visualize the higher-order organization of the native CatSper complex in intact mammalian sperm. The repeating CatSper units form long zigzag-rows along mouse and human sperm flagella. Above each tetrameric channel pore, most of the extracellular domains form a canopy that interconnects to a zigzag-shaped roof. Murine CatSper contains an additional wing-structure connected to the tetrameric channel. The intracellular domains link two neighboring channels to a diagonal array, suggesting a dimer formation. Fitting of an atomic model of isolated monomeric CatSper to the in situ map reveals supramolecular interactions and assembly of the CatSper complex. Loss of EFCAB9-CATSPERζ alters the architecture and interactions of the channels, resulting in fragmentation and misalignment of the zigzag-rows and disruption of flagellar movement in Efcab9-/- sperm. This work offers unique insights into the structural basis for understanding CatSper regulation of sperm motility.


Asunto(s)
Motilidad Espermática , Cola del Espermatozoide , Animales , Calcio/metabolismo , Canales de Calcio/fisiología , Membrana Celular/metabolismo , Masculino , Mamíferos/metabolismo , Ratones , Motilidad Espermática/fisiología , Cola del Espermatozoide/metabolismo , Espermatozoides/metabolismo
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