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1.
PLoS Negl Trop Dis ; 18(6): e0012263, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875307

RESUMO

Small terrestrial mammals are major hosts of infectious agents responsible for zoonotic diseases. Astroviruses (AstVs)-the cause of non-bacterial gastroenteritis mainly affecting young children-have been detected in a wide array of mammalian and avian host species. However, understanding the factors that influence AstV infection within and across hosts is limited. Here, we investigated the impact of land use changes on AstVs in terrestrial small mammals in rural northeastern Madagascar. We sampled 515 small mammals, representing seven endemic and four introduced species. Twenty-two positive samples were identified, all but one of which were found in the introduced species Mus musculus and Rattus rattus (family Muridae), with a positivity rate of 7.7% (6/78) and 5.6% (15/266), respectively. The non-introduced rodent case was from an endemic shrew-tenrec (family Tenrecidae). We found the highest positivity rate of AstVs infection in brushy regrowth (17.5%, 7/40) as compared to flooded rice fields (4.60%, 8/174), secondary forest (4.1%, 3/74), agroforest (3.6%, 1/28), village (2.61%, 3/115), and semi-intact forest (0%, 0/84). A phylogenetic analysis revealed an association between AstVs and their rodent host species. None of the viruses were phylogenetically related to AstVs previously described in Malagasy bats. This study supports AstV circulation in synanthropic animals in agricultural habitats of Madagascar and highlights the need to assess the spillover risk to human populations in rural areas.

3.
Exp Biol Med (Maywood) ; 249: 10069, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463388

Assuntos
Medicina , Biologia
4.
J Clin Transl Sci ; 8(1): e45, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476247

RESUMO

We assessed the rigor and reproducibility (R&R) activities of institutions funded by the National Center for Advancing Translational Sciences (NCTSA) through a survey and website search (N = 61). Of 50 institutional responses, 84% reported incorporating some form of R&R training, 68% reported devoted R&R training, 30% monitored R&R practices, and 10% incentivized them. Website searches revealed 9 (15%) freely available training curricula, and 7 (11%) institutional programs specifically created to enhance R&R. NCATS should formally integrate R&R principles into its translational science models and institutional requirements.

5.
NPJ Biofilms Microbiomes ; 10(1): 10, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310144

RESUMO

Otitis media (OM) is one of the most globally pervasive pediatric conditions. Translocation of nasopharynx-resident opportunistic pathogens like nontypeable Haemophilus influenzae (NTHi) assimilates into polymicrobial middle ear biofilms, which promote OM pathogenesis and substantially diminish antibiotic efficacy. Oral or tympanostomy tube (TT)-delivered antibiotics remain the standard of care (SOC) despite consequences including secondary infection, dysbiosis, and antimicrobial resistance. Monoclonal antibodies (mAb) against two biofilm-associated structural proteins, NTHi-specific type IV pilus PilA (anti-rsPilA) and protective tip-region epitopes of NTHi integration host factor (anti-tip-chimer), were previously shown to disrupt biofilms and restore antibiotic sensitivity in vitro. However, the additional criterion for clinical relevance includes the absence of consequential microbiome alterations. Here, nine chinchilla cohorts (n = 3/cohort) without disease were established to evaluate whether TT delivery of mAbs disrupted nasopharyngeal or fecal microbiomes relative to SOC-OM antibiotics. Cohort treatments included a 7d regimen of oral amoxicillin-clavulanate (AC) or 2d regimen of TT-delivered mAb, AC, Trimethoprim-sulfamethoxazole (TS), ofloxacin, or saline. Fecal and nasopharyngeal lavage (NPL) samples were collected before and several days post treatment (DPT) for 16S sequencing. While antibiotic-treated cohorts displayed beta-diversity shifts (PERMANOVA, P < 0.05) and reductions in alpha diversity (q < 0.20) relative to baseline, mAb antibodies failed to affect diversity, indicating maintenance of a eubiotic state. Taxonomic and longitudinal analyses showed blooms in opportunistic pathogens (ANCOM) and greater magnitudes of compositional change (P < 0.05) following broad-spectrum antibiotic but not mAb treatments. Collectively, results showed broad-spectrum antibiotics induced significant fecal and nasopharyngeal microbiome disruption regardless of delivery route. Excitingly, biofilm-targeting antibodies had little effect on fecal and nasopharyngeal microbiomes.


Assuntos
Antibacterianos , Otite Média , Animais , Criança , Humanos , Antibacterianos/uso terapêutico , Chinchila , Padrão de Cuidado , Otite Média/tratamento farmacológico , Orelha Média/patologia , Biofilmes , Nasofaringe/patologia
6.
NEJM Evid ; 3(1): EVIDoa2300003, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38320512

RESUMO

BACKGROUND: We have examined the primary efficacy results of 23,551 randomized clinical trials from the Cochrane Database of Systematic Reviews. METHODS: We estimate that the great majority of trials have much lower statistical power for actual effects than the 80 or 90% for the stated effect sizes. Consequently, "statistically significant" estimates tend to seriously overestimate actual treatment effects, "nonsignificant" results often correspond to important effects, and efforts to replicate often fail to achieve "significance" and may even appear to contradict initial results. To address these issues, we reinterpret the P value in terms of a reference population of studies that are, or could have been, in the Cochrane Database. RESULTS: This leads to an empirical guide for the interpretation of an observed P value from a "typical" clinical trial in terms of the degree of overestimation of the reported effect, the probability of the effect's sign being wrong, and the predictive power of the trial. CONCLUSIONS: Such an interpretation provides additional insight about the effect under study and can guard medical researchers against naive interpretations of the P value and overoptimistic effect sizes. Because many research fields suffer from low power, our results are also relevant outside the medical domain. (Funded by the U.S. Office of Naval Research.)


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Eur Urol Focus ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38195354

RESUMO

BACKGROUND: Accurate primary staging of renal cancer with conventional imaging is challenging. Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) may serve to improve the accuracy of renal cancer staging. OBJECTIVE: To determine clinicopathological and management differences for primary renal cancer staged with PSMA PET/CT in comparison to conventional imaging. DESIGN, SETTING, AND PARTICIPANTS: We conducted a retrospective cohort study of PSMA PET/CT scans performed for primary staging of renal cancer and incidental renal lesions at three sites in Brisbane, Australia between June 2015 and June 2020. Clinical characteristics, imaging, and histopathology were reviewed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Clinicopathological and management differences according to staging modality (PSMA PET/CT, conventional imaging) were assessed. Descriptive statistics were used to report demographics and clinical parameters. Nonparametric methods were used for statistical analysis. Fisher's exact test was used for comparison of small-cell size categorical variables. RESULTS AND LIMITATIONS: From a total of 120 PSMA PET/CT scans, 61 were included (52 staging, 9 incidental) for predominantly males (74%) with a mean age of 65.1 yr (standard deviation 12.0). Most primary lesions (40/51) were clear-cell renal cell carcinoma (ccRCC; 98% PSMA-avid), eight were non-ccRCC (75% PSMA-avid), and three were non-RCC (oncocytoma; 67% PSMA-avid). PSMA PET identified a greater number of presumed metastatic lesions than conventional imaging (195 vs 160). A management change was observed for 32% of patients (20% major, 12% minor). Limitations include the retrospective design and selection bias, lack of blinding to PSMA reporting, and the use of different PSMA radiotracers. CONCLUSIONS: PSMA PET/CT detected more metastases than conventional imaging and most renal cancers were PSMA-avid, resulting in a management change for one-third of the patients. PATIENT SUMMARY: We looked at a newer type of scan called PSMA PET/CT for first staging of kidney cancer. We found that this detects more metastasis and helps in decisions on changes in treatment for some patients. This type of imaging is a useful addition to conventional scans in tricky cases and may help in better selection of suitable treatments, but more studies are required.

8.
Am J Med Genet A ; 194(6): e63496, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38282294

RESUMO

In 2002, heterozygous suppressor of fused variants (SUFU+/-) in the germline were described to have a tumor suppressor role in the development of pediatric medulloblastoma (MB). Other neoplasms associated with pathologic germline SUFU+/- variants have also been described among patients with basal cell nevus syndrome (BCNS; BCNS is also known as Gorlin syndrome, nevoid basal cell carcinoma [BCC] syndrome or Gorlin-Goltz syndrome; OMIM 109400), an autosomal-dominant cancer predisposition syndrome. The phenotype of patients with germline SUFU+/- variants is very poorly characterized due to a paucity of large studies with long-term follow-up. As such, there is a clinical need to better characterize the spectrum of neoplasms among patients with germline SUFU+/- variants so that clinicians can provide accurate counseling and optimize tumor surveillance strategies. The objective of this study is to perform a scoping review to map the evidence on the rate of medulloblastoma and to describe the spectrum of other neoplasms among patients with germline SUFU+/- variants. A review of all published literature in PubMed (MEDLINE), EMBASE, Cochrane, and Web of Science were searched from the beginning of each respective database until October 9, 2021. Studies of pediatric and adult patients with a confirmed germline SUFU+/- variant who were evaluated for the presence of any neoplasm (benign or malignant) were included. There were 176 patients (N = 30 studies) identified with a confirmed germline SUFU+/- variant who met inclusion criteria. Data were extracted from two cohort studies, two case-control studies, 18 case series, and eight case reports. The median age at diagnosis of a germline SUFU+/- variant was 4.5 years where 44.4% identified as female and 13.4% of variants were de novo. There were 34 different neoplasms (benign and malignant) documented among patients with confirmed germline SUFU+/- variants, and the most common were medulloblastoma (N = 59 patients), BCC (N = 21 patients), and meningioma (N = 19 patients). The median age at medulloblastoma diagnosis was 1.42 years (range 0.083-3; interquartile range 1.2). When data were available for these three most frequent neoplasms (N = 95 patients), 31 patients (32.6%) had neither MB, BCC nor meningioma; 51 patients (53.7%) had one of medulloblastoma or BCC or meningioma; eight patients (8.4%) had two of medulloblastoma or BCC or meningioma, and five patients (5.3%) had medulloblastoma and BCC and meningioma. This is the first study to synthesize the data on the frequency and spectrum of neoplasms specifically among patients with a confirmed germline SUFU+/- variant. This scoping review is a necessary step forward in optimizing evidence-based tumor surveillance strategies for medulloblastoma and estimating the risk of other neoplasms that could impact patient outcomes.


Assuntos
Mutação em Linhagem Germinativa , Heterozigoto , Meduloblastoma , Proteínas Repressoras , Humanos , Meduloblastoma/genética , Meduloblastoma/patologia , Mutação em Linhagem Germinativa/genética , Predisposição Genética para Doença , Síndrome do Nevo Basocelular/genética , Síndrome do Nevo Basocelular/patologia , Masculino , Feminino , Criança
9.
Laryngoscope ; 134(4): 1564-1571, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37597166

RESUMO

OBJECTIVES: We examined sinus mucosal samples recovered from pediatric chronic rhinosinusitis (CRS) patients for the presence of Z-form extracellular DNA (eDNA) due to its recently elucidated role in pathogenesis of disease. Further, we immunolabeled these specimens for the presence of both members of the bacterial DNA-binding DNABII protein family, integration host factor (IHF) and histone-like protein (HU), due to their known role in converting common B-DNA to the rare Z-form. METHODS: Sinus mucosa samples recovered from 20 patients during functional endoscopic sinus surgery (FESS) were immunolabelled for B- and Z-DNA, as well as for both bacterial DNABII proteins. RESULTS: Nineteen of 20 samples (95%) included areas rich in eDNA, with the majority in the Z-form. Areas positive for B-DNA were restricted to the most distal regions of the mucosal specimen. Labeling for both DNABII proteins was observed on B- and Z-DNA, which aligned with the role of these proteins in the B-to-Z DNA conversion. CONCLUSIONS: Abundant Z-form eDNA in culture-positive pediatric CRS samples suggested that bacterial DNABII proteins were responsible for the conversion of eukaryotic B-DNA that had been released into the luminal space by PMNs during NETosis, to the Z-form. The presence of both DNABII proteins on B-DNA and Z-DNA supported the known role of these bacterial proteins in the B-to-Z DNA conversion. Given that Z-form DNA both stabilizes the bacterial biofilm and inactivates PMN NET-mediated killing of trapped bacteria, we hypothesize that this conversion may be contributing to the chronicity and recalcitrance of CRS to treatment. LEVEL OF EVIDENCE: NA Laryngoscope, 134:1564-1571, 2024.


Assuntos
DNA de Forma B , DNA Forma Z , Rinite , Sinusite , Humanos , Criança , Fatores Hospedeiros de Integração , Biofilmes , Sinusite/cirurgia , Doença Crônica , Rinite/cirurgia
10.
Biofilm ; 6: 100166, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38078059

RESUMO

Objectives: Structural or mucus hypersecretory pulmonary diseases such as cystic fibrosis (CF), wherein viscous mucus accumulates and clearance functions are impaired, predispose people to lung infection by inhaled bacteria that form biofilm aggregates. Nontuberculous mycobacteria (NTM), primarily Mycobacterium abscessus and Mycobacterium avium, are the growing cause of these lung infections and are extremely challenging to treat due to antibiotic recalcitrance. Better therapeutic approaches are urgently needed. We developed a humanized monoclonal antibody (HuTipMab) directed against a biofilm structural linchpin, the bacterial DNABII proteins, that rapidly disrupts biofilms and generates highly vulnerable newly released bacteria (NRel). Methods: HuTipMab's ability to recognize HupB, NTM's DNABII homologue was determined by ELISA. Relative ability of HuTipMab to disrupt biofilms formed by lab-passaged and clinical isolates of NTM was assessed by CLSM. Relative sensitivity of NTM NRel to antibiotic killing compared to when grown planktonically was evaluated by plate count. Results: HuTipMab recognized HupB and significantly disrupted NTM biofilms in a time- and dose-dependent manner. Importantly, NTM NRel of lab-passaged and clinical isolates were now highly sensitive to killing by amikacin and azithromycin. Conclusions: If successful, this combinatorial treatment strategy would empower existing antibiotics to more effectively kill NTM newly released from a biofilm by HuTipMab and thereby both improve clinical outcomes and perhaps decrease length of antibiotic treatment for people that are NTM culture-positive.

12.
Syst Parasitol ; 100(6): 745-750, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37874423

RESUMO

Ixodes (Afrixodes) ambohitantelensis n. sp. (Acari: Ixodidae) is described based on females ex endemic shrew tenrecs (Afrosoricida: Tenrecidae) and an introduced rodent (Rodentia: Muridae) from Madagascar. Females of this new species are similar to those of other species of the subgenus Afrixodes Morel, 1966, known from Madagascar, from which they can be distinguished by the size of scutum, size of scutal setae, shape of alloscutal setae, development of genital apron, size of auriculae, size of anterior angle of basis capituli, size of palpi, dental formula on hypostome, development of syncoxae, and size and development of spurs on coxae I and IV.


Assuntos
Ixodes , Ixodidae , Parasitos , Feminino , Animais , Tenrecidae , Roedores/parasitologia , Musaranhos , Muridae , Afrotheria , Madagáscar , Especificidade da Espécie
13.
Sci Rep ; 13(1): 17740, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872187

RESUMO

Necrotizing enterocolitis (NEC) is the leading cause of gastrointestinal-related death in premature infants. Its etiology is multifactorial, with intestinal dysbiosis playing a major role. Probiotics are a logical preventative therapy for NEC, however their benefits have been inconsistent. We previously developed a novel probiotic delivery system in which planktonic (free-living) Limosilactobacillus reuteri (Lr) is incubated with biocompatible dextranomer microspheres (DM) loaded with maltose (Lr-DM-maltose) to induce biofilm formation. Here we have investigated the effects of Lr-DM-maltose in an enteral feed-only piglet model of NEC. We found a significant decrease in the incidence of Definitive NEC (D-NEC), death associated with D-NEC, and activated microglia in the brains of piglets treated with Lr-DM-maltose compared to non-treated piglets. Microbiome analyses using 16S rRNA sequencing of colonic contents revealed a significantly different microbial community composition between piglets treated with Lr-DM-maltose compared to non-treated piglets, with an increase in Lactobacillaceae and a decrease in Clostridiaceae in Lr-DM-maltose-treated piglets. Furthermore, there was a significant decrease in the incidence of D-NEC between piglets treated with Lr-DM-maltose compared to planktonic Lr. These findings validate our previous results in rodents, and support future clinical trials of Lr in its biofilm state for the prevention of NEC in premature neonates.


Assuntos
Enterocolite Necrosante , Doenças do Recém-Nascido , Limosilactobacillus reuteri , Probióticos , Recém-Nascido , Animais , Humanos , Suínos , Enterocolite Necrosante/prevenção & controle , RNA Ribossômico 16S/genética , Maltose , Intestinos , Recém-Nascido Prematuro , Biofilmes , Encéfalo , Probióticos/farmacologia , Probióticos/uso terapêutico
14.
Microsc Microanal ; 29(Supplement_1): 2062-2063, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37612906
15.
Eur J Nucl Med Mol Imaging ; 51(1): 295-303, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37592084

RESUMO

PURPOSE: There is an emerging role of the use of Prostate-Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET) in renal cell carcinoma. Herein, we report our experience in use of PSMA PET in recurrent or metastatic renal cell carcinoma (RCC). METHODS: A retrospective analysis of all patients who underwent PSMA PET for suspected recurrent or de-novo metastatic RCC between 2015 and 2020 at three institutions was performed. The primary outcome was change in management (intensification or de-intensification) following PSMA PET scan. Secondary outcomes included histopathological correlation of PSMA avid sites, comparison of sites of disease on PSMA PET to diagnostic CT and time to systemic treatment.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Neoplasias da Próstata , Masculino , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/terapia , Carcinoma de Células Renais/patologia , Próstata/patologia , Estudos Retrospectivos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/terapia , Neoplasias Renais/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Neoplasias da Próstata/patologia , Radioisótopos de Gálio
16.
Front Microbiol ; 14: 1202215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564292

RESUMO

Introduction: The "silent" antimicrobial resistance (AMR) pandemic is responsible for nearly five million deaths annually, with a group of seven biofilm-forming pathogens, known as the ESKAPEE pathogens, responsible for 70% of these fatalities. Biofilm-resident bacteria, as they exist within the disease site, are canonically highly resistant to antibiotics. One strategy to counter AMR and improve disease resolution involves developing methods to disrupt biofilms. These methods aim to release bacteria from the protective biofilm matrix to facilitate their killing by antibiotics or immune effectors. Several laboratories working on such strategies have demonstrated that bacteria newly released from a biofilm display a transient phenotype of significantly increased susceptibility to antibiotics. Similarly, we developed an antibody-based approach for biofilm disruption directed against the two-membered DNABII family of bacterial DNA-binding proteins, which serve as linchpins to stabilize the biofilm matrix. The incubation of biofilms with α-DNABII antibodies rapidly collapses them to induce a population of newly released bacteria (NRel). Methods: In this study, we used a humanized monoclonal antibody (HuTipMab) directed against protective epitopes of a DNABII protein to determine if we could disrupt biofilms formed by the high-priority ESKAPEE pathogens as visualized by confocal laser scanning microscopy (CLSM) and COMSTAT2 analysis. Then, we demonstrated the potentiated killing of the induced NRel by seven diverse classes of traditional antibiotics by comparative plate count. Results: To this end, ESKAPEE biofilms were disrupted by 50%-79% using a single tested dose and treatment period with HuTipMab. The NRel of each biofilm were significantly more sensitive to killing than their planktonically grown counterparts (heretofore, considered to be the most sensitive to antibiotic-mediated killing), even when tested at a fraction of the MIC (1/250-1/2 MIC). Moreover, the bacteria that remained within the biofilms of two representative ESKAPEE pathogens after HuTipMab disruption were also significantly more susceptible to killing by antibiotics. Discussion: New data presented in this study support our continued development of a combinatorial therapy wherein HuTipMab is delivered to a patient with recalcitrant disease due to an ESKAPEE pathogen to disrupt a pathogenic biofilm, along with a co-delivered dose of an antibiotic whose ability to rapidly kill the induced NRel has been demonstrated. This novel regimen could provide a more successful clinical outcome to those with chronic, recurrent, or recalcitrant diseases, while limiting further contribution to AMR.

17.
Sci Rep ; 13(1): 12959, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563215

RESUMO

Bacterial biofilms contribute significantly to pathogenesis, recurrence and/or chronicity of the majority of bacterial diseases due to their notable recalcitrance to clearance. Herein, we examined kinetics of the enhanced sensitivity of nontypeable Haemophilus influenzae (NTHI) newly released (NRel) from biofilm residence by a monoclonal antibody against a bacterial DNABII protein (α-DNABII) to preferential killing by a ß-lactam antibiotic. This phenotype was detected within 5 min and lasted for ~ 6 h. Relative expression of genes selected due to their known involvement in sensitivity to a ß-lactam showed transient up-regulated expression of penicillin binding proteins by α-DNABII NTHI NRel, whereas there was limited expression of the ß-lactamase precursor. Transient down-regulated expression of mediators of oxidative stress supported similarly timed vulnerability to NADPH-oxidase sensitive intracellular killing by activated human PMNs. Further, transient up-regulated expression of the major NTHI porin aligned well with observed increased membrane permeability of α-DNABII NTHI NRel, a characteristic also shown by NRel of three additional pathogens. These data provide mechanistic insights as to the transient, yet highly vulnerable, α-DNABII NRel phenotype. This heightened understanding supports continued validation of this novel therapeutic approach designed to leverage knowledge of the α-DNABII NRel phenotype for more effective eradication of recalcitrant biofilm-related diseases.


Assuntos
Anticorpos Monoclonais , Matriz Extracelular de Substâncias Poliméricas , Humanos , Anticorpos Monoclonais/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Haemophilus influenzae/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Fenótipo , beta-Lactamas/metabolismo
18.
Pathogens ; 12(7)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37513706

RESUMO

Madagascar is home to an extraordinary diversity of endemic mammals hosting several zoonotic pathogens. Although the African origin of Malagasy mammals has been addressed for a number of volant and terrestrial taxa, the origin of their hosted zoonotic pathogens is currently unknown. Using bats and Leptospira infections as a model system, we tested whether Malagasy mammal hosts acquired these infections on the island following colonization events, or alternatively brought these bacteria from continental Africa. We first described the genetic diversity of pathogenic Leptospira infecting bats from Mozambique and then tested through analyses of molecular variance (AMOVA) whether the genetic diversity of Leptospira hosted by bats from Mozambique, Madagascar and Comoros is structured by geography or by their host phylogeny. This study reveals a wide diversity of Leptospira lineages shed by bats from Mozambique. AMOVA strongly supports that the diversity of Leptospira sequences obtained from bats sampled in Mozambique, Madagascar, and Comoros is structured according to bat phylogeny. Presented data show that a number of Leptospira lineages detected in bat congeners from continental Africa and Madagascar are imbedded within monophyletic clades, strongly suggesting that bat colonists have indeed originally crossed the Mozambique Channel while infected with pathogenic Leptospira.

19.
Mol Phylogenet Evol ; 188: 107890, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37517508

RESUMO

African-Malagasy species of the bat genus Miniopterus are notable both for the dramatic increase in the number of newly recognized species over the last 15 years, as well as for the profusion of new taxa from Madagascar and the neighboring Comoros. Since 2007, seven new Malagasy Miniopterus species have been described compared to only two new species since 1936 from the Afrotropics. The conservative morphology of Miniopterus and limited geographic sampling in continental Africa have undoubtedly contributed to the deficit of continental species. In addition to uncertainty over species limits, phylogenetic relationships of Miniopterus remain mostly unresolved, particularly at deeper backbone nodes. Previous phylogenetic studies were based on limited taxon sampling and/or limited genetic sampling involving no more than five loci. Here, we conduct the first phylogenomic study of the Afrotropical Miniopteridae by analyzing up to 3772 genome-wide ultraconserved elements (UCEs) from historic and modern samples of 70 individuals from 25 Miniopterus species/lineages. We analyze multiple datasets of varying degrees of completeness (70, 90, and 100 percent complete) using partitioned concatenated maximum likelihood and multispecies coalescent methods. Our well-supported, species-level phylogenies resolved most (6/8 or 7/8) backbone nodes and strongly support for the first time the monophyly of the Malagasy radiation. We inferred the crown age of African Miniopteridae in the late Miocene (10.4 Ma), while the main lineages of Miniopterus appear to have contemporaneously diversified in two sister radiations in the Afrotropics and Madagascar. Species-level divergence of 23 of 25 African + Malagasy Miniopterus were estimated to have 95 % HPDs that overlap with the late Miocene (5.3-10.4 Ma). We present ancestral range estimates that unambiguously support a continental African radiation that originated in the Zambezian and Somalian/Ethiopian biogeographic regions, but we cannot rule out back colonization of Africa from Madagascar. The phylogeny indicates genetic support for up to seven new species.


Assuntos
Quirópteros , Humanos , Animais , Filogenia , Quirópteros/genética , África , Madagáscar
20.
Lakartidningen ; 1202023 05 17.
Artigo em Sueco | MEDLINE | ID: mdl-37194364

RESUMO

The ¼replication crisis« refers to the crisis of confidence triggered by the failure to reproduce a large portion of important findings in several scientific disciplines, including medicine. Failed replication occurred in high-profiled scandals such as the ¼omics« case at Duke University, as well as in systematic attempts to reproduce influential preclinical studies. An extensive meta-research literature attests to problems with suboptimal methods choices and indicates that behaviors bordering between deliberate misleading and well-intentioned mistakes (questionable research practices) are very common (e.g. selective reporting of particular results ¼based on a gut feeling«). As a consequence, influential international institutions have been prompted to take action to strengthen research rigor and reproducibility. So-called reproducibility networks, pioneered in the UK, seem particularly promising to organize necessary coordinated efforts among a wide range of stakeholders.


Assuntos
Projetos de Pesquisa , Humanos , Reprodutibilidade dos Testes
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