Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 113
Filtrar
1.
J Am Chem Soc ; 145(47): 25776-25788, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37972287

RESUMO

Misfolded protein oligomers are of central importance in both the diagnosis and treatment of Alzheimer's and Parkinson's diseases. However, accurate high-throughput methods to detect and quantify oligomer populations are still needed. We present here a single-molecule approach for the detection and quantification of oligomeric species. The approach is based on the use of solid-state nanopores and multiplexed DNA barcoding to identify and characterize oligomers from multiple samples. We study α-synuclein oligomers in the presence of several small-molecule inhibitors of α-synuclein aggregation as an illustration of the potential applicability of this method to the development of diagnostic and therapeutic methods for Parkinson's disease.


Assuntos
Nanoporos , Doença de Parkinson , Humanos , alfa-Sinucleína/metabolismo , Doença de Parkinson/metabolismo
2.
J Lipid Res ; 64(12): 100469, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37922990

RESUMO

Deletion of the nuclear hormone receptor small heterodimer partner (Shp) ameliorates the development of obesity and nonalcoholic steatohepatitis (NASH) in mice. Liver-specific SHP plays a significant role in this amelioration. The gut microbiota has been associated with these metabolic disorders, and the interplay between bile acids (BAs) and gut microbiota contributes to various metabolic disorders. Since hepatic SHP is recognized as a critical regulator in BA synthesis, we assessed the involvement of gut microbiota in the antiobesity and anti-NASH phenotype of Shp-/- mice. Shp deletion significantly altered the levels of a few conjugated BAs. Sequencing the 16S rRNA gene in fecal samples collected from separately housed mice revealed apparent dysbiosis in Shp-/- mice. Cohousing Shp-/- mice with WT mice during a Western diet regimen impaired their metabolic improvement and effectively disrupted their distinctive microbiome structure, which became indistinguishable from that of WT mice. While the Western diet challenge significantly increased lipopolysaccharide and phenylacetic acid (PAA) levels in the blood of WT mice, their levels were not increased in Shp-/- mice. PAA was strongly associated with hepatic peroxisome proliferator-activated receptor gamma isoform 2 (Pparg2) activation in mice, which may represent the basis of the molecular mechanism underlying the association of gut bacteria and hepatic steatosis. Shp deletion reshapes the gut microbiota possibly by altering BAs. While lipopolysaccharide and PAA are the major driving forces derived from gut microbiota for NASH development, Shp deletion decreases these signaling molecules via dysbiosis, thereby partially protecting mice from diet-induced metabolic disorders.


Assuntos
Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Ácidos e Sais Biliares/metabolismo , Disbiose/genética , Disbiose/metabolismo , Lipopolissacarídeos/metabolismo , Fígado/metabolismo , Doenças Metabólicas/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , RNA Ribossômico 16S/metabolismo
3.
J Lipid Res ; 64(11): 100454, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37827334

RESUMO

Small heterodimer partner (SHP, Nr0b2) is an orphan nuclear receptor that regulates bile acid, lipid, and glucose metabolism. Shp-/- mice are resistant to diet-induced obesity and hepatic steatosis. In this study, we explored the potential role of SHP in the development of nonalcoholic steatohepatitis (NASH). A 6-month Western diet (WD) regimen was used to induce NASH. Shp deletion protected mice from NASH progression by inhibiting inflammatory and fibrotic genes, oxidative stress, and macrophage infiltration. WD feeding disrupted the ultrastructure of hepatic mitochondria in WT mice but not in Shp-/- mice. In ApoE-/- mice, Shp deletion also effectively ameliorated hepatic inflammation after a 1 week WD regimen without an apparent antisteatotic effect. Moreover, Shp-/- mice resisted fibrogenesis induced by a methionine- and choline-deficient diet. Notably, the observed protection against NASH was recapitulated in liver-specific Shp-/- mice fed either the WD or methionine- and choline-deficient diet. Hepatic cholesterol was consistently reduced in the studied mouse models with Shp deletion. Our data suggest that Shp deficiency ameliorates NASH development likely by modulating hepatic cholesterol metabolism and inflammation.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Colesterol/metabolismo , Colina , Inflamação/metabolismo , Fígado/metabolismo , Metionina , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo
4.
Int J Artif Organs ; 45(10): 841-848, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35903013

RESUMO

INTRODUCTION: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is the fastest way to restore circulation in refractory cardiogenic shock, however it cannot unload the failing left ventricle. There is a lack of consensus regarding optimal approach to left ventricular venting in V-A ECMO patients with severely depressed or absent left ventricular function. METHODS: A computer model was developed in Matlab Simulink R20016b (MathWorks, Inc., Natick, MA, USA) to analyze different venting options as well as atrial septostomy in the setting of cardiogenic shock and V-A ECMO. RESULTS: The model has shown an inverse linear relationship between left atrial pressure and either vent, Impella or atrial septum defect flow rate. The minimum vent flow required to prevent pulmonary edema in complete loss of left ventricular function needed to be higher than the bronchial blood flow. Atrial septostomy restored normal pulmonary blood flow with low left atrial pressure but induced stasis in the left ventricle. Venting the pulmonary artery induced stasis in the entire pulmonary circulation as well as left atrium and left ventricle. Venting the left ventricle directly with a cannula or Impella device avoided blood stasis. CONCLUSION: Our data suggest that reduction of left atrial pressure is linearly related to the vent, Impella or atrial septal defect flow rate. The preferred vent location is the left ventricle as it avoids stasis in the pulmonary circulation and cardiac chambers.


Assuntos
Oxigenação por Membrana Extracorpórea , Comunicação Interatrial , Simulação por Computador , Oxigenação por Membrana Extracorpórea/efeitos adversos , Ventrículos do Coração , Humanos , Choque Cardiogênico/terapia , Função Ventricular Esquerda
5.
Hepatol Commun ; 6(10): 2765-2780, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35866568

RESUMO

Bile acid-CoA: amino acid N-acyltransferase (BAAT) catalyzes bile acid conjugation, the last step in bile acid synthesis. BAAT gene mutation in humans results in hypercholanemia, growth retardation, and fat-soluble vitamin insufficiency. The current study investigated the physiological function of BAAT in bile acid and lipid metabolism using Baat-/- mice. The bile acid composition and hepatic gene expression were analyzed in 10-week-old Baat-/- mice. They were also challenged with a westernized diet (WD) for additional 15 weeks to assess the role of BAAT in bile acid, lipid, and glucose metabolism. Comprehensive lab animal monitoring system and cecal 16S ribosomal RNA gene sequencing were used to evaluate the energy metabolism and microbiome structure of the mice, respectively. In Baat-/- mice, hepatic bile acids were mostly unconjugated and their levels were significantly increased compared with wild-type mice. Bile acid polyhydroxylation was markedly up-regulated to detoxify unconjugated bile acid accumulated in Baat-/- mice. Although the level of serum marker of bile acid synthesis, 7α-hydroxy-4-cholesten-3-one, was higher in Baat-/- mice, their bile acid pool size was smaller. When fed a WD, the Baat-/- mice showed a compromised body weight gain and impaired insulin secretion. The gut microbiome of Baat-/- mice showed a low level of sulfidogenic bacteria Bilophila. Conclusion: Mouse BAAT is the major taurine-conjugating enzyme. Its deletion protected the animals from diet-induced obesity, but caused glucose intolerance. The gut microbiome of the Baat-/- mice was altered to accommodate the unconjugated bile acid pool.


Assuntos
Disbiose , Metabolismo dos Lipídeos , Aciltransferases/genética , Aminoácidos/metabolismo , Animais , Ácidos e Sais Biliares , Coenzima A/metabolismo , Glucose , Humanos , Hiperfagia , Metabolismo dos Lipídeos/genética , Lipídeos , Camundongos , Taurina , Vitaminas
6.
Parasite Epidemiol Control ; 11: e00183, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33072898

RESUMO

The prevalence of Loa loa, Onchocerca volvulus and Wuchereria bancrofti infections in an under-surveyed area of Bengo Province, Angola, was determined by surveying 22 communities with a combination of clinical, serological and DNA diagnostics. Additional information was collected on participants' duration of residency, access to mass drug administration, knowledge of insect vectors and use of bednets. A total of 1616 individuals (38.1% male: 61.9% female), with an average age of 43 years, were examined. For L. loa, 6.2% (n = 100/16616) individuals were found to have eyeworm, based on the rapid assessment procedure for loiasis (RAPLOA) surveys, and 11.5% (n =178/1543) based on nested PCR analyses of venous blood. L. loa prevalences in long-term residents (>10 years) and older individuals (>60 years) were significantly higher, and older men with eyeworm were better informed about Chrysops vectors. For O. volvulus, 4.7% (n = 74/1567) individuals were found to be positive by enzyme-linked immunosorbent assay (Ov 16 ELISA), with only three individuals reporting to have ever taken ivermectin. For W. bancrofti, no infections were found using the antigen-based immunochromatographic test (ICT) and real-time PCR analysis; however, 27 individuals presented with lymphatic filariasis (LF) related clinical conditions (lymphoedema = 11, hydrocoele = 14, both = 2). Just under half (45.5%) of the participants owned a bednet, with the majority (71.1%) sleeping under it the night before. Our approach of using combination diagnostics reveals the age-prevalence of loiasis alongside low endemicity of onchocerciasis and LF. Future research foci should be on identifying opportunities for more cost-effective ways to eliminate onchocerciasis and to develop innovative surveillance modalities for clinical LF for individual disease management and disability prevention.

7.
Radiol Case Rep ; 14(2): 171-174, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30416639

RESUMO

Intestinal hypoganglionosis or isolated hypoganglionosis is a rare entity with a clinical and radiologic presentation that can mimic Hirschsprung's disease in the neonatal period. The diagnosis of this entity can be challenging with suction rectal biopsies that are standard for diagnosing Hirschsprung's disease. We present this case of congenital intestinal hypoganglionosis detailing the neonatal course, due to its rarity and the conundrums faced before an eventual diagnosis could be rendered. This case also illustrates the role of full thickness rectal biopsy in selected cases such as ours where the radiologic features are typical of Hirschsprung's, despite negative suction biopsies.

8.
Malar J ; 17(1): 420, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30419917

RESUMO

BACKGROUND: Anopheles mosquitoes impose an immense burden on the African population in terms of both human health and comfort. Uganda, in particular, boasts one of the highest malaria transmission rates in the world and its entire population is at risk for infection. Despite the immense burden these mosquitoes pose on the country, very few programmes exist that directly combat the issue at the vector control level and even fewer programmes focus on the vector in its most vulnerable juvenile stages. This study utilizes remote sensing techniques and spatial autocorrelation models to identify and prioritize the most prolific Anopheline larval habitats for control purposes in a rural community in Uganda. METHODS: A community-based mosquito surveillance programme was developed and implemented in Papoli Parish in Eastern Uganda over a 4-month period. Each day, a trained field team sampled the larval habitats of Anopheles mosquitoes within the population-dense areas of the community. Habitats and their productivity were identified and plotted spatially on a daily basis. Daily output was combined and displayed as a weekly habitat time-series. Additional spatial analysis was conducted using the Global and Anselin's Local Moran's I statistic to assess habitat spatial autocorrelation. RESULTS: Spatial models were developed to identify highly significant habitats and dictated the priority of these habitats for larval control purposes. Weekly time-series models identified the locations and productivity of each habitat, while Local Moran's I cluster maps identified statistically significant clusters (Cluster: High) and outliers (High Outlier) that were then interpreted for control priority. Models were stitched together in a temporal format to visually demonstrate the spatial shift of statically significant, high priority habitats over the entire study period. DISCUSSION: The findings show that the spatial outcomes of productive habitats can be made starkly apparent through initial habitat modelling and resulting time-series output. However, mosquito control resources are often limited and it is at this point that the Local Moran's I statistics demonstrates its value. Focusing on habitats identified as Cluster: High and High Outlier outputs allow for the identification of the most influential larval habitats. Utilizing this method for malaria control allows for the optimization of control resources in a real time, community driven, fashion, as well as providing a framework for future control practices.


Assuntos
Distribuição Animal , Anopheles/fisiologia , Ecossistema , Larva/fisiologia , Animais , Anopheles/crescimento & desenvolvimento , Participação da Comunidade , Sistemas de Informação Geográfica , Larva/crescimento & desenvolvimento , Modelos Teóricos , Tecnologia de Sensoriamento Remoto , Análise Espaço-Temporal , Uganda
9.
BMC Nephrol ; 19(1): 9, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329518

RESUMO

BACKGROUND: Thrombotic microangiopathy (TMA) secondary to gemcitabine therapy (GiTMA) is a very rare pathology that carries a poor prognosis, with nearly half of the cases progressing to end stage renal disease. GiTMA is most commonly associated with adenocarcinomas, most notably pancreatic cancers. The mainstay of management is withdrawal of the offending drug and supportive care. Plasmapheresis has a limited role and hemodialysis may help in the management of fluid overload secondary to renal failure. Furthermore, a C5 inhibitor, eculizumab, has been successfully used in the treatment of GiTMA. CASE PRESENTATION: A 64-year-old Caucasian female with history of pancreatic adenocarcinoma on gemcitabine chemotherapy presented with signs and symptoms of fluid overload and was found to have abnormal kidney function. Her BP was 195/110 mmHg, serum creatinine 4.48 mg/dl, hemoglobin 8.2 g/dl, platelets 53 × 103/cmm, lactate dehydrogenase 540 IU/L, and was found to have schistocytes on blood film. A diagnosis of TMA secondary to gemcitabine therapy was suspected. Hemodialysis for volume overload and daily plasmapheresis were initiated. After six days of plasmapheresis, renal function did not improve. Further work up revealed ADAMTS 13 activity >15%, low C3, and stool culture and Shiga-toxin PCR were negative. Renal biopsy was consistent with TMA. Gemcitabine was discontinued, but renal function failed to improve and eculizumab therapy was considered due to suspicion of aHUS. Serum creatinine >2.26 mg/dl and a platelet count of >/= 30 × 109/L is highly suggestive of aHUS, while TTP is more likely when creatinine is <2.26 mg/dl and platelet count of <30 × 109/L. She received intravenous eculizumab for eight months, which resulted in significant improvement of renal function. Other markers of hemolysis, namely LDH and bilirubin, also rapidly improved following eculizumab therapy. Plasmapheresis and hemodialysis were discontinued after two and eight weeks of initiation respectively. CONCLUSION: Chemotherapy induced TMA is very rare and requires a high index of clinical suspicion for timely diagnosis. Discontinuation of the offending drug and supportive care is the main stay of treatment; however, eculizumab has been shown to be beneficial in GiTMA. Further research is required to validate this approach.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/análogos & derivados , Microangiopatias Trombóticas/induzido quimicamente , Microangiopatias Trombóticas/tratamento farmacológico , Desoxicitidina/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Microangiopatias Trombóticas/diagnóstico , Gencitabina
10.
J Am Mosq Control Assoc ; 34(1): 47-49, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-31442111

RESUMO

Automobile tires discarded in urban forest fragments may be a public health hazard, as they can support a population of vector mosquitoes. However, little is known about what factors may affect mosquito abundance and diversity within waste tires in a freshwater wetland forest. This study aimed to determine whether mosquito population dynamics in this environment in Florida differed over a year due to the site of collection and variation in vegetation greenness and elevation. We constructed negative binomial regression models to determine which of these characteristics were significant (α = 0.05) in affecting mosquito count data. Our findings suggest that in this specific environment, none of the covariates scrutinized had significant impacts on modulating overall mosquito and Aedes albopictus (the dominant species) abundance; waste tire habitats in urban freshwater wetland forests may be a year-round public health hazard.


Assuntos
Biodiversidade , Culicidae , Áreas Alagadas , Animais , Florida , Dinâmica Populacional
11.
Urology ; 110: 184-191, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28826877

RESUMO

Renal cystic lesions are considered the most common abnormality associated with the kidneys. Most renal cysts are usually uncomplicated simple cysts that are not life-threatening; however, fatal renal cystic diseases can develop from these space-occupying lesions. Although renal cystic diseases are similar in presentation, they possess distinct features, variable prognoses, and complications later in life. Early identification and effective management of these respected diseases has led to longer survival rates and better quality of life. The purpose of this review is to provide a comprehensive analysis of the most prevalent cystic diseases of the pediatric population in hopes to aid in early distinction and appropriate treatment.


Assuntos
Doenças Renais Císticas , Criança , Humanos , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/terapia
12.
J Nephropathol ; 6(2): 53-57, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28491853

RESUMO

BACKGROUND: Acute interstitial nephritis (AIN) is a clinico-pathological syndrome associated with a variety of infections, drugs, and sometimes with unknown causes. It is a common cause of acute kidney injury (AKI) and subsequent renal impairment, which often times is under-diagnosed. Infection-associated AIN occurs as a consequence of many systemic bacterial, viral, and parasitic infec-tions; however, its incidence has decreased significantly after the advent of antimicrobials. Infection-associated AIN presents with both oliguric or non-oliguric renal insufficiency, without the classical clinical triad of AIN (fever, rash, and arthralgia). In this scenario the renal function is usually reversible after the infection is treated. In most cases, patients with acute renal failure present with extra-renal manifestations typically detected in underlying infections. Renal biopsy serves as the most definitive test for both the diagnosis and prognosis of AIN. CASE PRESENTATION: In this paper, we will address one such case of biopsy-proven AIN. In this case, the patient presented with severe AKI induced by anaerobic streptococcus, leading to a periodontal abscess, which was successfully treated with corticosteroids and requiring renal replacement therapy (RRT). CONCLUSIONS: AIN should be considered in the differential for unexplained AKI. Initial management should include conservative therapy by withdrawing any suspected causative agent. Renal biopsy is needed for confirmation in cases where kidney function fails to improve within 5-7 days on conservative therapy. Risk of immunosuppression is very important to consider when giving steroids in patients with infection induced AIN, and steroids may have to be delayed until the active infection is completely controlled.

13.
Parasite Epidemiol Control ; 2(3): 71-84, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29774284

RESUMO

The Republic of Angola is a priority country for onchocerciasis and lymphatic filariasis (LF) elimination, however, the co-distribution of the filarial parasite Loa loa (loiasis) is a significant impediment, due to the risk of severe adverse events (SAEs) associated with ivermectin used in mass drug administration (MDA) campaigns. Angola has a high risk loiasis zone identified in Bengo Province where alternative interventions may need to be implemented; however, the presence and geographical overlap of the three filarial infections/diseases are not well defined. Therefore, this study conducted a rapid integrated filarial mapping survey based on readily identifiable clinical conditions of each disease in this risk zone to help determine prevalence and co-distribution patterns in a timely manner with limited resources. In total, 2007 individuals from 29 communities in five provincial municipalities were surveyed. Community prevalence estimates were determined by the rapid assessment procedure for loiasis (RAPLOA) and rapid epidemiological mapping of onchocerciasis (REMO) together with two questions on LF clinical manifestations (presence of lymphoedema, hydrocoele). Overall low levels of endemicity, with different overlapping distributions were found. Loiasis was found in 18 communities with a prevalence of 2.0% (31/1571), which contrasted to previous results defining the area as a high risk zone. Onchocerciasis prevalence was 5.3% (49/922) in eight communities, and LF prevalence was 0.4% for lymphoedema (8/2007) and 2.6% for hydrocoeles (20/761 males) in seven and 12 communities respectively. The clinical mapping survey method helped to highlight that all three filarial infections are present in this zone of Bengo Province. However, the significant difference in loiasis prevalence found between the past and this current survey suggests that further studies including serological and parasitological confirmation are required. This will help determine levels of infection and risk, understand the associations between clinical, serological and parasitological prevalence patterns, and better determine the most appropriate treatment strategies to reach onchocerciasis and LF elimination targets in the loiasis co-endemic areas. Our results also suggest that the utility of the earlier RAPLOA derived maps, based on surveys undertaken over a decade ago, are likely to be invalid given the extent of population movement and environmental change, particularly deforestation, and that fine scale micro-mapping is required to more precisely delineate the interventions required defined by these complex co-endemicities.

14.
J Transl Med ; 13: 260, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26260800

RESUMO

BACKGROUND: The American College of Obstetrics and Gynecology (ACOG) and Maternal Fetal Medicine (MFM) Societies recommended that abnormal cfDNA fetal results should be confirmed by amniocentesis and karyotyping. Our results demonstrate that normal cfDNA results inconsistent with high-resolution abnormal ultrasounds should be confirmed by karyotyping following a substantial frequency of incorrect cfDNA results. METHODS: Historical review of our ~4,000 signed prenatal karyotypes found ~24% of reported abnormalities would not have been detected by cfDNA. Akron Children's Hospital Cytogenetics Laboratory has completed 28 abnormal cfDNA cases among the 112 amniocenteses karyotyped. RESULTS: Following abnormal cfDNA results our karyotypes confirmed only 60% of the cfDNA results were consistent. Our cases found a normal cfDNA test result followed by a 20 weeks anatomical ultrasound detected a false negative trisomy 18 cfDNA result. One cfDNA result that reported trisomy 21 in the fetus was confirmed by karyotyping which also added an originally undetected balanced reciprocal translocation. Another reported karyotyped case followed by a repeated microarray of pure fetal DNA, together revealed one phenotypically normal newborn with a complex mosaic karyotype substantially decreasing the newborn's eventual reproductive fitness. This second case establishes the importance of karyotyping the placenta and cord or peripheral blood when inconsistent or mosaic results are identified following an abnormal cfDNA result with a normal newborn phenotype without a prenatal karyotype. CONCLUSIONS: These Maternal Fetal Medicine referrals demonstrate that positive NIPT results identify an increased abnormal karyotypic frequency as well as a substantial proportion of discordant fetal results. Our results found: (1) a normal NIPT test result followed by a 20 week anatomical ultrasound detected a false negative trisomy 18 NIPT result, (2) a substantial proportion of abnormal NIPT tests identify chromosomal mosaicism that may or may not be confined to the placenta, (3) follow up karyotyping should be completed on the newborn placenta and peripheral blood when the amniocyte karyotype does not confirm the NIPT reported abnormality in order to identify ongoing risk of developing mosaic symptoms, and (4) karyotyping all high risk fetuses tested by amniocentesis defines the 24% of chromosome abnormalities not currently screened by NIPT.


Assuntos
Análise Citogenética , DNA/sangue , DNA/genética , Feto/metabolismo , Mosaicismo , Placenta/metabolismo , Amniocentese , Bandeamento Cromossômico , Cromossomos Humanos X/genética , Síndrome de Down/genética , Reações Falso-Negativas , Feminino , Genótipo , Humanos , Indóis/metabolismo , Recém-Nascido , Cariotipagem , Masculino , Análise em Microsséries , Gravidez , Diagnóstico Pré-Natal , Translocação Genética , Trissomia
15.
PLoS Negl Trop Dis ; 7(7): e2342, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936571

RESUMO

BACKGROUND: Recently, most onchocerciasis control programs have begun to focus on elimination. Developing an effective elimination strategy relies upon accurately mapping the extent of endemic foci. In areas of Africa that suffer from a lack of infrastructure and/or political instability, developing such accurate maps has been difficult. Onchocerciasis foci are localized near breeding sites for the black fly vectors of the infection. The goal of this study was to conduct ground validation studies to evaluate the sensitivity and specificity of a remote sensing model developed to predict S. damnosum s.l. breeding sites. METHODOLOGY/PRINCIPAL FINDINGS: Remote sensing images from Togo were analyzed to identify areas containing signature characteristics of S. damnosum s.l. breeding habitat. All 30 sites with the spectral signature were found to contain S. damnosum larvae, while 0/52 other sites judged as likely to contain larvae were found to contain larvae. The model was then used to predict breeding sites in Northern Uganda. This area is hyper-endemic for onchocerciasis, but political instability had precluded mass distribution of ivermectin until 2009. Ground validation revealed that 23/25 sites with the signature contained S. damnosum larvae, while 8/10 sites examined lacking the signature were larvae free. Sites predicted to have larvae contained significantly more larvae than those that lacked the signature. CONCLUSIONS/SIGNIFICANCE: This study suggests that a signature extracted from remote sensing images may be used to predict the location of S. damnosum s.l. breeding sites with a high degree of accuracy. This method should be of assistance in predicting communities at risk for onchocerciasis in areas of Africa where ground-based epidemiological surveys are difficult to implement.


Assuntos
Entomologia/métodos , Tecnologia de Sensoriamento Remoto/métodos , Simuliidae/crescimento & desenvolvimento , Animais , Ecossistema , Humanos , Sensibilidade e Especificidade , Togo , Uganda
16.
J Am Mosq Control Assoc ; 29(2): 108-22, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23923325

RESUMO

Understanding the geographic role of different species of mosquito vectors and vertebrate hosts in West Nile virus (WNV) transmission cycles can facilitate the development and implementation of targeted surveillance and control measures. This study examined the relationship between WNV-antibody rates in birds and mosquito infection rates and bloodfeeding patterns in east-central Illinois. The earliest detection of WNV-RNA by reverse transcription-polymerase chain reaction TaqMan was from Culex restuans; however, amplification typically coincided with an increase in abundance of Cx. pipiens. Trap type influenced annual estimates of infection rates in Culex species, as well as estimation of blood meal source. Bird species with the highest WNV-antibody rates (i.e., Mourning Doves [Zenaida macroura], Northern Cardinals [Cardinalis cardinalis], American Robins [Turdus migratorius], and House Sparrows [Passer domesticus]) were also the common species found in Culex blood meals. Although antibody rates were not directly proportional to estimated avian abundance, the apparent availability of mammal species did influence proportion of mammal to bird blood meals. Antibody prevalence in the American Robin was lower than expected based on the strong attraction of Culex to American Robins for blood meals. Age-related differences in serology were evident, antibody rates increased in older groups of robins and sparrows, whereas 1st-year hatch and older adults of Mourning Doves and Northern Cardinals had equally high rates of antibody-positive serum samples. The vector and host interactions observed in east-central Illinois (Champaign County), an urban area surrounded by agriculture, are compared to studies in the densely population areas of southern Cook County.


Assuntos
Doenças das Aves/virologia , Culex/virologia , Insetos Vetores/virologia , Febre do Nilo Ocidental/transmissão , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Doenças das Aves/sangue , Aves , Culex/fisiologia , Comportamento Alimentar , Humanos , Illinois/epidemiologia , Insetos Vetores/fisiologia , Densidade Demográfica , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Estudos Soroepidemiológicos , Especificidade da Espécie , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia
17.
Geo Spat Inf Sci ; 15(2): 117-133, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23504576

RESUMO

The standard methods for regression analyses of clustered riverine larval habitat data of Simulium damnosum s.l. a major black-fly vector of Onchoceriasis, postulate models relating observational ecological-sampled parameter estimators to prolific habitats without accounting for residual intra-cluster error correlation effects. Generally, this correlation comes from two sources: (1) the design of the random effects and their assumed covariance from the multiple levels within the regression model; and, (2) the correlation structure of the residuals. Unfortunately, inconspicuous errors in residual intra-cluster correlation estimates can overstate precision in forecasted S.damnosum s.l. riverine larval habitat explanatory attributes regardless how they are treated (e.g., independent, autoregressive, Toeplitz, etc). In this research, the geographical locations for multiple riverine-based S. damnosum s.l. larval ecosystem habitats sampled from 2 pre-established epidemiological sites in Togo were identified and recorded from July 2009 to June 2010. Initially the data was aggregated into proc genmod. An agglomerative hierarchical residual cluster-based analysis was then performed. The sampled clustered study site data was then analyzed for statistical correlations using Monthly Biting Rates (MBR). Euclidean distance measurements and terrain-related geomorphological statistics were then generated in ArcGIS. A digital overlay was then performed also in ArcGIS using the georeferenced ground coordinates of high and low density clusters stratified by Annual Biting Rates (ABR). This data was overlain onto multitemporal sub-meter pixel resolution satellite data (i.e., QuickBird 0.61m wavbands ). Orthogonal spatial filter eigenvectors were then generated in SAS/GIS. Univariate and non-linear regression-based models (i.e., Logistic, Poisson and Negative Binomial) were also employed to determine probability distributions and to identify statistically significant parameter estimators from the sampled data. Thereafter, Durbin-Watson test statistics were used to test the null hypothesis that the regression residuals were not autocorrelated against the alternative that the residuals followed an autoregressive process in AUTOREG. Bayesian uncertainty matrices were also constructed employing normal priors for each of the sampled estimators in PROC MCMC. The residuals revealed both spatially structured and unstructured error effects in the high and low ABR-stratified clusters. The analyses also revealed that the estimators, levels of turbidity and presence of rocks were statistically significant for the high-ABR-stratified clusters, while the estimators distance between habitats and floating vegetation were important for the low-ABR-stratified cluster. Varying and constant coefficient regression models, ABR- stratified GIS-generated clusters, sub-meter resolution satellite imagery, a robust residual intra-cluster diagnostic test, MBR-based histograms, eigendecomposition spatial filter algorithms and Bayesian matrices can enable accurate autoregressive estimation of latent uncertainity affects and other residual error probabilities (i.e., heteroskedasticity) for testing correlations between georeferenced S. damnosum s.l. riverine larval habitat estimators. The asymptotic distribution of the resulting residual adjusted intra-cluster predictor error autocovariate coefficients can thereafter be established while estimates of the asymptotic variance can lead to the construction of approximate confidence intervals for accurately targeting productive S. damnosum s.l habitats based on spatiotemporal field-sampled count data.

18.
J Vector Ecol ; 36(1): 86-93, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21635645

RESUMO

An immunoassay using monoclonal antibodies (MAbs) that are specific for different vertebrate taxa (from class to species) has been developed that simplifies and facilitates analysis of vertebrate blood meals from arthropod vectors. The MAbs have been prepared against the single protein albumin, the most abundant protein in vertebrate sera. A panel of these antibodies has been generated against albumins from 33 species of vertebrates, representing four classes, 15 orders, and 25 families. Immunoreactivity of albumin in mosquito blood meals can be detected as late as 48 h after feeding. Immunoassays with MAbs can be carried out in the field as well as the laboratory. Used in conjunction with nucleic acid assays or used alone with an appropriate assortment of antibodies, the assay is simple, sensitive, and unambiguous.


Assuntos
Albuminas/análise , Albuminas/imunologia , Anticorpos Monoclonais/imunologia , Artrópodes , Vertebrados/sangue , Vertebrados/metabolismo , Animais , Anticorpos Monoclonais/biossíntese , Imunoensaio , Camundongos , Camundongos Endogâmicos BALB C
19.
Scand J Urol Nephrol ; 45(6): 473-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21612326

RESUMO

Renal complications of Waldenström's macroglobulinemia (WM) are rarely observed. Nephrotic syndrome in association with WM has most often been secondary to amyloidosis. This article reports a case of WM with nephrotic syndrome as a result of membranous nephropathy with immunoglobulin M (IgM) deposition. A 44-year-old male diagnosed with WM 4 years previously, presented with heavy proteinuria (7.8 g/24 h). Kidney biopsy revealed expanded mesangium, thickened capillary loops and epimembranous spikes, with no significant interstitial inflammation or thickened tubular basement membranes. Immunofluorescence examination demonstrated strong granular staining of IgM and λ chains, with weaker C3 and C1q staining. Electron microscopy showed many subepithelial dense deposits, and fewer large subendothelial dense deposits. Treatment was directed at the patient's WM with maintenance rituximab and fludarabine. Subsequently, decreases were seen in both the patient's serum IgM and serum viscosity. With therapy for WM and the addition of an angiotensin receptor blocker, the patient's proteinuria also improved, from 7.8 g to 4.8 g/24 h. The patient continued to follow up with his hematologist and in 2009 creatinine was 1 mg/dl (76.26 ?mol/l), with a 24 h urine protein excretion of 0.159 g.


Assuntos
Glomerulonefrite Membranosa/imunologia , Síndrome Nefrótica/imunologia , Macroglobulinemia de Waldenstrom/complicações , Adulto , Antagonistas de Receptores de Angiotensina/uso terapêutico , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Glomerulonefrite Membranosa/complicações , Glomerulonefrite Membranosa/patologia , Humanos , Imunoglobulina M/sangue , Cadeias lambda de Imunoglobulina/sangue , Masculino , Síndrome Nefrótica/complicações , Síndrome Nefrótica/patologia , Rituximab , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Macroglobulinemia de Waldenstrom/tratamento farmacológico
20.
PLoS One ; 6(1): e15996, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-21283732

RESUMO

An improved knowledge of mosquito life history could strengthen malaria vector control efforts that primarily focus on killing mosquitoes indoors using insecticide treated nets and indoor residual spraying. Natural sugar sources, usually floral nectars of plants, are a primary energy resource for adult mosquitoes but their role in regulating the dynamics of mosquito populations is unclear. To determine how the sugar availability impacts Anopheles sergentii populations, mark-release-recapture studies were conducted in two oases in Israel with either absence or presence of the local primary sugar source, flowering Acacia raddiana trees. Compared with population estimates from the sugar-rich oasis, An. sergentii in the sugar-poor oasis showed smaller population size (37,494 vs. 85,595), lower survival rates (0.72 vs. 0.93), and prolonged gonotrophic cycles (3.33 vs. 2.36 days). The estimated number of females older than the extrinsic incubation period of malaria (10 days) in the sugar rich site was 4 times greater than in the sugar poor site. Sugar feeding detected in mosquito guts in the sugar-rich site was significantly higher (73%) than in the sugar-poor site (48%). In contrast, plant tissue feeding (poor quality sugar source) in the sugar-rich habitat was much less (0.3%) than in the sugar-poor site (30%). More important, the estimated vectorial capacity, a standard measure of malaria transmission potential, was more than 250-fold higher in the sugar-rich oasis than that in the sugar-poor site. Our results convincingly show that the availability of sugar sources in the local environment is a major determinant regulating the dynamics of mosquito populations and their vector potential, suggesting that control interventions targeting sugar-feeding mosquitoes pose a promising tactic for combating transmission of malaria parasites and other pathogens.


Assuntos
Anopheles/metabolismo , Metabolismo dos Carboidratos , Comportamento Alimentar/fisiologia , Malária/prevenção & controle , Controle de Mosquitos/métodos , Acacia/química , Animais , Malária/transmissão , Plantas/química , Dinâmica Populacional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...