RESUMO
Modern drug development increasingly requires comprehensive models that can be utilized in the earliest stages of compound and target discovery. Here we report a phenotypic screening exercise in a high-throughput Organ-on-a-Chip setup. We assessed the inhibitory effect of 1537 protein kinase inhibitors in an angiogenesis assay. Over 4000 micro-vessels were grown under perfusion flow in microfluidic chips, exposed to a cocktail of pro-angiogenic factors and subsequently exposed to the respective kinase inhibitors. Efficacy of compounds was evaluated by reduced angiogenic sprouting, whereas reduced integrity of the main micro-vessel was taken as a measure for toxicity. The screen yielded 53 hits with high anti-angiogenicity and low toxicity, of which 44 were previously unassociated with angiogenic pathways. This study demonstrates that Organ-on-a-Chip models can be screened in high numbers to identify novel compounds and targets. This will ultimately reduce bias in early-stage drug development and increases probability to identify first in class compounds and targets for today's intractable diseases.
Assuntos
Angiogênese , Antineoplásicos , Humanos , Sistemas Microfisiológicos , Antineoplásicos/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Recent studies suggest that both stem- and crown-group Archosauria encompassed high ecological diversity during their initial Triassic radiation. We describe a new pseudosuchian archosaur, Benggwigwishingasuchus eremicarminis gen. et sp. nov., from the Anisian (Middle Triassic) Fossil Hill Member of the Favret Formation (Nevada, USA), a pelagic setting in the eastern Panthalassan Ocean characterized by the presence of abundant ammonoids and large-bodied ichthyosaurs. Coupled with archosauriforms from the eastern and western Tethys Ocean, Benggwigwishingasuchus reveals that pseudosuchians were also components of Panthalassan ocean coastal settings, establishing that the group occupied these habitats globally during the Middle Triassic. However, Benggwigwishingasuchus, Qianosuchus, and Ticinosuchus (two other pseudosuchians known from marine sediments) are not recovered in a monophyletic group, demonstrating that a nearshore marine lifestyle occurred widely across Archosauriformes during this time. Benggwigwishingasuchus is recovered as part of an expanded Poposauroidea, including several taxa (e.g. Mandasuchus, Mambawakalae) from the Middle Triassic Manda Beds of Tanzania among its basally branching members. This implies a greater undiscovered diversity of poposauroids during the Early Triassic, and supports that the group, and pseudosuchians more broadly, diversified rapidly following the End-Permian mass extinction.
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Fósseis , Animais , Fósseis/anatomia & histologia , Nevada , Filogenia , Répteis/anatomia & histologia , Répteis/classificação , Evolução Biológica , EcossistemaRESUMO
PURPOSE: To evaluate feasibility, internal consistency, inter-rater reliability, and prospective validity of AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting. METHODS: Patients were included from four trauma centers. Two surgeons with substantial amount of experience in spine trauma care were included from each center. Two separate questionnaires were administered at baseline, 6-months and 1-year: one to surgeons (mainly CROST) and another to patients (AO Spine PROST-Patient Reported Outcome Spine Trauma). Descriptive statistics were used to analyze patient characteristics and feasibility, Cronbach's α for internal consistency. Inter-rater reliability through exact agreement, Kappa statistics and Intraclass Correlation Coefficient (ICC). Prospective analysis, and relationships between CROST and PROST were explored through descriptive statistics and Spearman correlations. RESULTS: In total, 92 patients were included. CROST showed excellent feasibility results. Internal consistency (α = 0.58-0.70) and reliability (ICC = 0.52 and 0.55) were moderate. Mean total scores between surgeons only differed 0.2-0.9 with exact agreement 48.9-57.6%. Exact agreement per CROST item showed good results (73.9-98.9%). Kappa statistics revealed moderate agreement for most CROST items. In the prospective analysis a trend was only seen when no concerns at all were expressed by the surgeon (CROST = 0), and moderate to strong positive Spearman correlations were found between CROST at baseline and the scores at follow-up (rs = 0.41-0.64). Comparing the CROST with PROST showed no specific association, nor any Spearman correlations (rs = -0.33-0.07). CONCLUSIONS: The AO Spine CROST showed moderate validity in a true clinical setting including patients from the daily clinical practice.
Assuntos
Traumatismos da Coluna Vertebral , Humanos , Reprodutibilidade dos Testes , Traumatismos da Coluna Vertebral/cirurgia , Coluna Vertebral , Inquéritos e Questionários , Medidas de Resultados Relatados pelo PacienteRESUMO
INTRODUCTION: Spinal neurostimulation is a therapy for otherwise intractable chronic pain. Spinal neurostimulation includes stimulation of the spinal cord (SCS), dorsal root ganglion (DRGS), and dorsal root entry zone (DREZS). New paresthesia-free neurostimulation paradigms may rely on different mechanisms of action from those of conventional tonic neurostimulation. The aim of this systematic review is to assess the existing knowledge on the effect of spinal neurostimulation on somatosensory processing in patients with chronic pain. We therefore reviewed the existing literature on the effect of various spinal neurostimulation paradigms on the supraspinal somatosensory evoked response (SER). MATERIALS AND METHODS: Multiple scientific data bases were searched for studies that assessed the effect of spinal neurostimulation on the supraspinal SER, evoked by painful or nonpainful peripheral stimuli in patients with chronic pain. We found 205 studies, of which 24 were included. Demographic data, study design, and study outcome were extracted. RESULTS: Of the 24 included studies, 23 used electroencephalography to assess the SER; one study used magnetoencephalography. Fifteen studies evaluated tonic SCS; six studies (also) evaluated paresthesia-free paradigms; three studies evaluated the effect of tonic DRGS or DREZS. Sixteen studies used nonpainful stimuli to elicit the SER, 14 observed a decreased SER amplitude. Ten studies used painful stimuli to elicit the SER, yielding mixed results. DISCUSSION: The included studies suggest that both paresthesia-based and paresthesia-free spinal neurostimulation paradigms can decrease (part of) the SER elicited by a nonpainful peripheral stimulus. The observed SER amplitude reduction likely is the effect of various spinal and supraspinal mechanisms of spinal neurostimulation that also contribute to pain relief. CONCLUSIONS: Spinal neurostimulation modulates the processing of a peripherally applied nonpainful stimulus. For painful stimuli, the results are not conclusive. It is not yet clear whether paresthesia-free neurostimulation affects the SER differently from paresthesia-based neurostimulation.
Assuntos
Potenciais Somatossensoriais Evocados , Estimulação da Medula Espinal , Humanos , Potenciais Somatossensoriais Evocados/fisiologia , Estimulação da Medula Espinal/métodos , Medula Espinal/fisiologia , Dor Crônica/terapia , Dor Crônica/fisiopatologiaRESUMO
OBJECTIVE: We performed a 1-year evaluation of a novel strategy of simultaneously analyzing single nucleotide variants (SNVs), copy number variants (CNVs) and copy-number-neutral Absence-of-Heterozygosity from Whole Exome Sequencing (WES) data for prenatal diagnosis of fetuses with ultrasound (US) anomalies and a non-causative QF-PCR result. METHODS: After invasive diagnostics, whole exome parent-offspring trio-sequencing with exome-wide CNV analysis was performed in pregnancies with fetal US anomalies and a non-causative QF-PCR result (WES-CNV). On request, additional SNV-analysis, restricted to (the) requested gene panel(s) only (with the option of whole exome SNV-analysis afterward) was performed simultaneously (WES-CNV/SNV) or as rapid SNV-re-analysis, following a normal CNV analysis. RESULTS: In total, 415 prenatal samples were included. Following a non-causative QF-PCR result, WES-CNV analysis was initially requested for 74.3% of the chorionic villus (CV) samples and 45% of the amniotic fluid (AF) samples. In case WES-CNV analysis did not reveal a causative aberration, SNV-re-analysis was requested in 41.7% of the CV samples and 17.5% of the AF samples. All initial analyses could be finished within 2 weeks after sampling. For SNV-re-analysis during pregnancy, turn-around-times (TATs) varied between one and 8 days. CONCLUSION: We show a highly efficient all-in-one WES-based strategy, with short TATs, and the option of rapid SNV-re-analysis after a normal CNV result.
Assuntos
Variações do Número de Cópias de DNA , Feto , Gravidez , Feminino , Humanos , Sequenciamento do Exoma , Heterozigoto , Feto/diagnóstico por imagem , Feto/anormalidades , NucleotídeosRESUMO
Stereospondyli are a clade of large aquatic temnospondyls known to have evolved a large dermal pectoral girdle. Among the Stereospondyli, metoposaurids in particular possess large interclavicles and clavicles relative to the rest of the postcranial skeleton. Because of the large size of these dermal bones, it was first proposed that they served as ballast during hydrostatic buoyancy control which assisted metoposaurids to live a bottom-dwelling mode of life. However, a large bone need not necessarily be heavy, for which determining the bone compactness becomes crucial for understanding any such adaptation in these dermal bones. Previous studies on the evolution of bone adaptations to aquatic lifestyles such as osteosclerosis, pachyostosis, osteoporotic-like pattern and pachyosteosclerosis have been observed in the long bones of secondarily aquatic amniotes. However, there are no known studies on the analysis of bone compactness in the dermal pectoral girdle of non-amniote taxa including Temnospondyli. This study looks at evidence of changes in bone mass adaptations in the dermal bones of the pectoral girdle of two stereospondyls occurring in the Late Triassic KrasiejÏw locality (Southwestern Poland), namely: Metoposaurus krasiejowensis and Cyclotosaurus intermedius. However, because of lack of research on bone compactness of temnospondyls in general, there is no existent frame of reference to infer bone mass increase (BMI) in the M. krasiejowensis samples, and thus the bone compactness results of this taxon are compared with that of the samples of C. intermedius. Results of this study indicate that the interclavicles of M. krasiejowensis partially evolved BMI-like condition rendering these bones to be heavy enough to get selected as ballast during hydrostatic buoyancy control. Additionally, M. krasiejowensis shared its habitat with C. intermedius, however, the dermal pectoral girdle sample of the latter taxon does not display signs of BMI-like condition. Furthermore, the absence of variation in hydrostatic buoyancy control in the ontogenetic series of interclavicles of M. krasiejowensis could imply lack of ontogenetic niche shift along the water column.
Assuntos
Anfíbios , Osso e Ossos , Animais , Densidade Óssea , Adaptação Fisiológica , Clavícula/anatomia & histologia , Evolução Biológica , FósseisRESUMO
OBJECTIVES: Previous literature showed that the diagnostic accuracy of computed tomographic angiography (CTA) is not equally comparable with that of the rarely used golden standard of digital subtraction angiography (DSA) for detecting blunt cerebrovascular injuries (BCVI) in trauma patients. However, advances in CTA technology may prove CTA to become equally accurate. This study investigated the diagnostic accuracy of CTA in detecting BCVI in comparison with DSA in trauma patients. METHODS: An electronic database search was performed in PubMed, EMBASE, and Cochrane Library. Summary estimates of sensitivity, specificity, positive and negative likelihood, diagnostic odds ratio, and 95% confidence intervals were determined using a bivariate random-effects model. RESULTS: Of the 3293 studies identified, 9 met the inclusion criteria. Pooled sensitivity was 64% (95% CI, 53-74%) and specificity 95% (95% CI, 87-99%) The estimated positive likelihood ratio was 11.8 (95%, 5.6-24.9), with a negative likelihood ratio of 0.38 (95%, 0.30-0.49) and a diagnostic odds ratio of 31 (95%, 17-56). CONCLUSION: CTA has reasonable specificity but low sensitivity when compared to DSA in diagnosing any BCVI. An increase in channels to 64 slices did not yield better sensitivity. There is a risk for underdiagnosis of BCVI when only using DSA to confirm CTA-positive cases, especially in those patients with low-grade injuries. KEY POINTS: ⢠Low sensitivity and high specificity were seen in identifying BCVI with CTA as compared to DSA. ⢠Increased CTA detector channels (≤ 64) did not lead to higher sensitivity when detecting BCVI. ⢠The use of CTA instead of DSA may lead to underdiagnosis and, consequently, undertreatment of BCVI.
Assuntos
Traumatismo Cerebrovascular , Ferimentos não Penetrantes , Angiografia Digital/métodos , Angiografia Cerebral , Traumatismo Cerebrovascular/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Humanos , Sensibilidade e Especificidade , Ferimentos não Penetrantes/diagnóstico por imagemRESUMO
BACKGROUND: The aim of this study was to assess the feasibility and diagnostic accuracy of an optimized 111 Indium-diethylenetriamine-penta-acetic-acid single-photon-emission computed tomography (CT) (111 In-DTPA SPECT-CT) examination in patients with suspected intrathecal drug delivery (ITDD) failure. MATERIALS AND METHODS: Retrospective analysis of routinely collected observational data from a case series of patients in the setting of the academic Center for Pain Medicine, Departments of Radiology and Nuclear Medicine and Neurosurgery. Twenty-seven patients participated between January 2014 and January 2019. Thirty-six optimized examinations including standardized pump flow rate with additional SPECT-CT imaging and a stepwise standardized analysis were performed. A 10 mL mixture of medication and 20 MBq 111In-DTPA was injected into the pump reservoir. Planar and SPECT-CT images were acquired at 24, 48, and 72 hours (h) after injection and at 96 hours and/or seven days, if needed. All images were reassessed by the first two authors using an optimized procedure. RESULTS AND CONCLUSIONS: Twenty-two abnormalities were identified in 21 examinations, with these abnormalities consisting of leakage (n = 7), spinal catheter obstruction (n = 7), and cerebrospinal fluid flow obstruction (n = 8). Interventions (n = 19) confirmed the cause of ITDD failure. A false-positive finding at follow-up (n = 1) and a false-negative finding (n = 1) were encountered. Sensitivity was 95% (20/21) and the specificity 93% (14/15). A significant difference (p < 0.001) was found between the accuracy of the conventical and the optimized analysis. The optimized 111 In-DTPA SPECT-CT examination is a powerful diagnostic tool for detecting the cause of ITDD failure.
Assuntos
Preparações Farmacêuticas , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Cintilografia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: The objective of this study was to assess the effectiveness of a low-dose intravenous S-ketamine treatment on refractory pain in patients with Complex Regional Pain Syndrome (CRPS). METHODS: In this retrospective study, patients with CRPS who received intravenous S-ketamine from March 2010 to April 2019 were included. According to our inpatient protocol, S-ketamine dose was increased until pain reduction was achieved or side effects were observed. Maximum dose was 14 mg/h and treatment duration was 7 days. Primary outcome parameters were pain scores (Numeric Rating Scale) at baseline (T0), end of infusion (T1), and approximately 4 weeks postinfusion (T2). Patients were categorized as responder/nonresponder at T1 and T2. Patients were considered a responder in case there was pain score reduction of greater than or equal to 2 points or if treatment was reported as successful. RESULTS: Forty-eight patients were included. Mean disease duration was 5 years (interquartile range [IQR] = 6 years). Median pain score significantly decreased from 8 (IQR = 2) at T0 to 6 (IQR = 4) at T1 (p < 0.001). At T1, 62% of the patients were responders. At T2, 48% of the patients remained a responder. A significant proportion of the responders at T1 turned into nonresponders at T2 (p = 0.03). CONCLUSION: In a group of patients with CRPS with refractory pain, low-dose intravenous S-ketamine treatment resulted in effective pain relief during infusion. Although a significant proportion of initial responders became nonresponders at follow-up, half of the patients were still a responder at ~ 4 weeks postinfusion. Further research is needed to investigate mechanisms responsible for pain relief by S-ketamine infusions and to ascertain possible predictors of response to the treatment.
Assuntos
Síndromes da Dor Regional Complexa , Dor Intratável , Analgésicos/uso terapêutico , Síndromes da Dor Regional Complexa/tratamento farmacológico , Humanos , Infusões Intravenosas , Ketamina , Dor Intratável/tratamento farmacológico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Temnospondyli are commonly believed to have possessed four digits in the manus and five in the pes. However, actual finds of articulated autopodia are extremely rare. Therefore, an articulated, slightly incomplete forelimb skeleton with preserved manus of Metoposaurus krasiejowensis from the Late Triassic of Poland is important in providing new details about the structure and ossification sequence in the temnospondyl limb. The most important observation is the presence of five metacarpals in this specimen. This allows reconstructing the manus as pentadactyl. The number of phalanges and the distribution of distal articulation facets allow reconstruction of the digit formula as (2?)-3-3-(3?)-(2?). The well-developed fifth digit suggests that the Metoposaurus manus shows a unique ossification sequence: the reduction or late ossification of the first digit conforms to the amniote-frog pattern, and the early development of the second and third digit makes Metoposaurus similar to salamanders. Based on the distribution of pentadactyly vs. tetradactyly in the temnospondyl manus, the number of digits was not phylogenetically constrained in temnospondyls, similar to today's amphibians.
Assuntos
Anfíbios/anatomia & histologia , Evolução Biológica , Membro Anterior/anatomia & histologia , Animais , Fósseis , Filogenia , PolôniaRESUMO
The growing number of bacterial strains resistant to therapeutic agents has been surpassing the various antibiotics developed by the chemical and pharmaceutical industries. This problem has driven the development of research using agents with antimicrobial potential, with an emphasis on plant-derived natural products. This study evaluated the chemical compounds present in Eucalyptus citriodora essential oil (EOEc) cultivated in northeastern Brazil and its properties as an antibacterial agent and resistance modifier against methicillin-resistant Staphylococcus aureus (MRSA) and ß-lactamase-producing strains. The EOEc was obtained using the hydrodistillation method, later analyzed by GC/MS, presenting a total of twelve compounds, with citronellal (65.45%); citronellol (14.87%); isopulegol (11.80%) and citronellyl acetate (2.51%) as its main constituents. The microdilution test was used to determine the minimum inhibitory concentration (MIC) and the bacterial resistance modulation of the essential oil. The EOEc did not present significant activity against the tested strains (MIC > 1000 µg mL-1). However, when evaluating the capacity of the EOEc to modify the resistance of S. aureus and E. coli strains to different antimicrobials, synergistic effects were obtained with reduced MIC values for all tested antibiotics being obtained. The EOEc showed antimicrobial and ß-lactam optimizing potential against resistant strains, presenting itself as a possible alternative for the use of these drugs at concentrations lower than those indicated against resistant strains.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Eucalyptus/química , Óleos Voláteis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Testes de Sensibilidade MicrobianaRESUMO
PURPOSE: To report on the development of AOSpine CROST (Clinician Reported Outcome Spine Trauma) and results of an initial reliability study. METHODS: The AOSpine CROST was developed using an iterative approach of multiple cycles of development, review, and revision including an expert clinician panel. Subsequently, a reliability study was performed among an expert panel who were provided with 20 spine trauma cases, administered twice with 4-week interval. The results of the developmental process were analyzed using descriptive statistics, the reliability per parameter using Kappa statistics, inter-rater rater agreement using intraclass correlation coefficient (ICC), and internal consistency using Cronbach's α. RESULTS: The AOSpine CROST was developed and consisted of 10 parameters, 2 of which are only applicable for surgically treated patents ('Wound healing' and 'Implants'). A dichotomous scoring system ('yes' or 'no' response) was incorporated to express expected problems for the short term and long term. In the reliability study, 16 (84.2%) participated in the first round and 14 (73.7%) in the second. Intra-rater reliability was fair to good for both time points (κ = 0.40-0.80 and κ = 0.31-0.67). Results of inter-rater reliability were lower (κ = 0.18-0.60 and κ = 0.16-0.46). Inter-rater agreement for total scores showed moderate results (ICC = 0.52-0.60), and the internal consistency was acceptable (α = 0.76-0.82). CONCLUSIONS: The AOSpine CROST, an outcome tool for the surgeons, was developed using an iterative process. An initial reliability analysis showed fair to moderate results and acceptable internal consistency. Further clinical validation studies will be performed to further validate the tool.
Assuntos
Traumatismos da Coluna Vertebral , Cirurgiões , Humanos , Variações Dependentes do Observador , Medidas de Resultados Relatados pelo Paciente , Reprodutibilidade dos TestesRESUMO
The unrestrained growth of tumor cells is generally attributed to mutations in essential growth control genes, but tumor cells are also affected by, or even addicted to, signals from the microenvironment. As therapeutic targets, these extrinsic signals may be equally significant as mutated oncogenes. In multiple myeloma (MM), a plasma cell malignancy, most tumors display hallmarks of active Wnt signaling but lack activating Wnt-pathway mutations, suggesting activation by autocrine Wnt ligands and/or paracrine Wnts emanating from the bone marrow (BM) niche. Here, we report a pivotal role for the R-spondin/leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) axis in driving aberrant Wnt/ß-catenin signaling in MM. We show that LGR4 is expressed by MM plasma cells, but not by normal plasma cells or B cells. This aberrant LGR4 expression is driven by IL-6/STAT3 signaling and allows MM cells to hijack R-spondins produced by (pre)osteoblasts in the BM niche, resulting in Wnt (co)receptor stabilization and a dramatically increased sensitivity to auto- and paracrine Wnts. Our study identifies aberrant R-spondin/LGR4 signaling with consequent deregulation of Wnt (co)receptor turnover as a driver of oncogenic Wnt/ß-catenin signaling in MM cells. These results advocate targeting of the LGR4/R-spondin interaction as a therapeutic strategy in MM.
Assuntos
Glicoproteínas de Membrana/metabolismo , Mieloma Múltiplo/metabolismo , Osteoblastos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Linhagem Celular Tumoral , Células HEK293 , Humanos , Interleucina-6/metabolismo , Ligantes , Camundongos , Ligação Proteica/fisiologia , Fator de Transcrição STAT3/metabolismo , beta Catenina/metabolismoRESUMO
OBJECTIVES: Intrathecal drug delivery is used for the treatment of intractable spasticity, dystonia, and pain. When the symptomatology fails to respond to therapy, the cause could be failure of the medication infusion. The purpose of this study is to assess pump catheter access port (CAP)-myelography and CAP-CT-myelography as advanced imaging methods in treatment failure. MATERIALS AND METHODS: We analyzed observational routinely collected data of 70 CAP procedures with 2D/3D reconstructions and additional imaging of 53 adult patients where the cause of treatment was unclear between November 2013 and November 2018. CAP-myelography and CAP-CT myelography were performed with postprocessing 2D/3D reconstructions. When myelography could not be obtained or when the result did not reveal the cause of the treatment failure, additional procedures, such as noncontrast CT, MRI, lumbar puncture CT, and 111Indium-DTPA SPECT-CT, were performed. RESULTS: CAP fluid aspiration prior to contrast medium injection was not possible (N = 17). In one case, contrast was injected into the pump pocket unintentionally (N = 1). Of 70 procedures, 24% were unaspiratable. The remaining CAP myelography examinations (N = 52) had limited value for the diagnosis. CAP-CT myelography (N = 50) was normal (N = 31). The abnormal results (N = 19) were dorsal dural leak (N = 5), subdural catheter position (N = 2), limited rostral flow of contrast material (N = 4), limited and abnormal contrast distribution (N = 3), obstruction of rostral flow (N = 2), a leak at the pump-catheter connection (N = 1), and a sheared catheter localized in the pump pocket (N = 2). Limited contrast distributions were found to be false positive findings (N = 2). Four normal CT-CAP myelographic procedures were false negatives, as the reference tests revealed a cause of intrathecal drug delivery (ITDD) failure. The CAP-CT procedures resulted in a sensitivity of 81% (17/21) and a specificity of 93% (27/29). CONCLUSIONS: CAP-CT myelography with 2D/3D reconstructions is an essential step in the diagnostic algorithm for cases involving ITDD failure.
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Sistemas de Liberação de Medicamentos , Injeções Espinhais , Mielografia , Adulto , Catéteres , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
Multi- and extensively drug-resistant tuberculosis (M/XDR-TB) has become an increasing threat not only in countries where the TB burden is high but also in affluent regions, due to increased international travel and globalization. Carbapenems are earmarked as potentially active drugs for the treatment of Mycobacterium tuberculosis To better understand the potential of carbapenems for the treatment of M/XDR-TB, the aim of this review was to evaluate the literature on currently available in vitro, in vivo, and clinical data on carbapenems in the treatment of M. tuberculosis and to detect knowledge gaps, in order to target future research. In February 2018, a systematic literature search of PubMed and Web of Science was performed. Overall, the results of the studies identified in this review, which used a variety of carbapenem susceptibility tests on clinical and laboratory strains of M. tuberculosis, are consistent. In vitro, the activity of carbapenems against M. tuberculosis is increased when used in combination with clavulanate, a BLaC inhibitor. However, clavulanate is not commercially available alone, and therefore, it is impossible in practice to prescribe carbapenems in combination with clavulanate at this time. Few in vivo studies have been performed, including one prospective, two observational, and seven retrospective clinical studies to assess the effectiveness, safety, and tolerability of three different carbapenems (imipenem, meropenem, and ertapenem). We found no clear evidence at the present time to select one particular carbapenem among the different candidate compounds to design an effective M/XDR-TB regimen. Therefore, more clinical evidence and dose optimization substantiated by hollow-fiber infection studies are needed to support repurposing carbapenems for the treatment of M/XDR-TB.
Assuntos
Carbapenêmicos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade , Animais , Ertapenem/uso terapêutico , Feminino , Imipenem/uso terapêutico , Meropeném/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Estudos ProspectivosRESUMO
OBJECTIVES: Patients with intractable spasticity treated with intrathecal baclofen (ITB) need regular evaluation and aftercare in an outpatient clinic or pain clinic setting. Logistically, this can be challenging. A solution could be to perform treatment at the patient's home setting. In the Netherlands, a project of the Dutch Healthcare Authority was initiated to deliver ambulatory ITB-related services via a home-based Ambulant Care Clinic. This aftercare is performed by nurse practitioners (NP) with support from a medical specialist. The scope of the study was to investigate the efficiency and safety of ITB-care for patients with severe disabling spasticity in their home setting. MATERIALS AND METHODS: A retrospective analysis of prospectively collected data. Patients with congenital or acquired spasticity were treated with ITB (1st April 2011 to January 1st 2016) using an implanted programmable pump system were referred to the home-based Ambulant Care Clinic by various neuromodulation centers in the Netherlands. All study parameters were a part of the standard intake and follow-up documentation. RESULTS: Of the 900 patients treated with ITB in the Netherlands, 239 were referred to the home-based Ambulant Care Clinic and included in this study. Mean age was 45.5 (range 7-82) years; 52% lived at home; the average satisfaction score was 9 (scale 0-10); and 0.29% had (serious) adverse events (60% of clinical manifestations were prevented by remote double-check control). Certifications for patient safety and quality standards were obtained. CONCLUSIONS: The concept of ITB aftercare on location demonstrated efficacy and safety in the described setting. For troubleshooting, close collaboration with a neuromodulation center is necessary and can be arranged in chain-based care.
Assuntos
Assistência ao Convalescente/métodos , Baclofeno/administração & dosagem , Serviços de Assistência Domiciliar , Injeções Espinhais/métodos , Relaxantes Musculares Centrais/administração & dosagem , Espasticidade Muscular/tratamento farmacológico , Adolescente , Adulto , Assistência ao Convalescente/normas , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Serviços de Assistência Domiciliar/normas , Humanos , Bombas de Infusão Implantáveis/normas , Injeções Espinhais/normas , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/epidemiologia , Países Baixos/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND & AIMS: Resistance of metastatic human colorectal cancer cells to drugs that block epidermal growth factor (EGF) receptor signaling could be caused by aberrant activity of other receptor tyrosine kinases, activating overlapping signaling pathways. One of these receptor tyrosine kinases could be MET, the receptor for hepatocyte growth factor (HGF). We investigated how MET signaling, and its interaction with CD44 (a putative MET coreceptor regulated by Wnt signaling and highly expressed by intestinal stem cells [ISCs] and adenomas) affects intestinal homeostasis, regeneration, and adenoma formation in mini-gut organoids and mice. METHODS: We established organoid cultures from ISCs stimulated with HGF or EGF and assessed intestinal differentiation by immunohistochemistry. Mice with total epithelial disruption of MET (AhCre/Metfl/fl/LacZ) or ISC-specific disruption of MET (Lgr5Creert2/Metfl/fl/LacZ) and control mice (AhCre/Met+/+/LacZ, Lgr5Creert2/Met+/+/LacZ) were exposed to 10 Gy total body irradiation; intestinal tissues were collected, and homeostasis and regeneration were assessed by immunohistochemistry. We investigated adenoma organoid expansion stimulated by HGF or EGF using adenomas derived from Lgr5Creert2/Metfl/fl/Apcfl/fl and Lgr5Creert2/Met+/+/Apcfl/fl mice. The same mice were evaluated for adenoma prevalence and size. We also quantified adenomas in AhCre/Metfl/fl/Apcfl/+ mice compared with AhCre/Met+/+/Apcfl/+ control mice. We studied expansion of organoids generated from crypts and adenomas, stimulated by HGF or EGF, that were derived from mice expressing different CD44 splice variants (Cd44+/+, Cd44-/-, Cd44s/s, or Cd44v4-10/v4-10 mice). RESULTS: Crypts incubated with EGF or HGF expanded into self-organizing mini-guts with similar levels of efficacy and contained all differentiated cell lineages. MET-deficient mice did not have defects in intestinal homeostasis. Total body irradiation reduced numbers of proliferating crypts in AhCre/Metfl/fl/LacZ mice. Lgr5Creert2/Metfl/fl/LacZ mice had impaired regeneration of MET-deficient ISCs. Adenoma organoids stimulated with EGF or HGF expanded to almost twice the size of nonstimulated organoids. MET-deficient adenoma organoids did not respond to HGF stimulation, but did respond to EGF. ISC-specific disruption of Met (Lgr5Creert2/Metfl/fl/Apcfl/fl mice) caused a twofold increase in apoptosis in microadenomas, resulting in an approximately 50% reduction of microadenoma numbers and significantly reduced average adenoma size. Total epithelial disruption of Met (AhCre/Metfl/fl/Apcfl/+ mice) resulted in an approximate 50% reduction in (micro)adenoma numbers. Intestinal crypts from Cd44-/- mice did not expand to the same extent as crypts from Cd44+/+ mice on stimulation with HGF, but had the same response to EGF. The negative effect on HGF-mediated growth was overcome by expression of CD44v4-10, but not by CD44s. Similarly, HGF-mediated expansion of adenoma organoids required CD44v4-10. CONCLUSIONS: In studies of intestinal organoid cultures and mice with inducible deletion of MET, we found HGF receptor signaling to regulate intestinal homeostasis and regeneration, as well as adenoma formation. These activities of MET are promoted by the stem cell CD44 isoform CD44v4-10. Our findings provide rationale for targeting signaling via MET and CD44 during anti-EGF receptor therapy of patients with colorectal cancer or in patients resistant to EGF receptor inhibitors.
Assuntos
Adenoma/metabolismo , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Receptores de Hialuronatos/metabolismo , Neoplasias Intestinais/metabolismo , Intestinos/enzimologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Regeneração , Células-Tronco/enzimologia , Adenoma/genética , Adenoma/patologia , Animais , Diferenciação Celular , Linhagem da Célula , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Cultivadas , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Genótipo , Fator de Crescimento de Hepatócito/farmacologia , Homeostase , Receptores de Hialuronatos/genética , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Intestinos/efeitos da radiação , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Proteínas Proto-Oncogênicas c-met/genética , Regeneração/efeitos dos fármacos , Regeneração/efeitos da radiação , Transdução de Sinais , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia , Células-Tronco/efeitos da radiação , Fatores de Tempo , Técnicas de Cultura de Tecidos , Carga TumoralRESUMO
The toothless beak of modern birds was considered as an adaption for feeding ecology; however, several recent studies suggested that developmental factors are also responsible for the toothless beak. Neontological and palaeontological studies have progressively uncovered how birds evolved toothless beaks and suggested that the multiple occurrences of complete edentulism in non-avian dinosaurs were the result of selection for specialized diets. Although developmental biology and ecological factors are not mutually exclusive, the conventional hypothesis that ecological factors account for the toothless beak appears insufficient. A recent study on dinosaur incubation period using embryonic teeth posited that tooth formation rate limits developmental speed, constraining toothed dinosaur incubation to slow reptilian rates. We suggest that selection for tooth loss was a side effect of selection for fast embryo growth and thus shorter incubation. This observation would also explain the multiple occurrences of tooth loss and beaks in non-avian dinosaur taxa crownward of Tyrannosaurus Whereas our hypothesis is an observation without any experimental supports, more studies of gene regulation of tooth formation in embryos would allow testing for the trade-off between incubation period and tooth development.
Assuntos
Bico/embriologia , Evolução Biológica , Aves/embriologia , Dinossauros/embriologia , Animais , Fósseis , Filogenia , Dente/embriologiaRESUMO
Air sacs are an important component of the avian respiratory system, and corresponding structures also were crucial for the evolution of sauropod dinosaur gigantism. Inferring the presence of air sacs in fossils so far is restricted to bones preserving internal pneumatic cavities and foramina as osteological correlates. We here present bone histological correlates for air sacs as a new potential identification tool for these elements of the respiratory system. The analysis of several avian and non-avian dinosaur samples revealed delicate fibres in secondary trabecular and secondary endosteal bone that in the former case (birds) is known or in the latter (non-avian dinosaurs) assumed to have been in contact with air sacs, respectively. The bone histology of this 'pneumosteal tissue' is markedly different from those regions where muscles attached presenting classical Sharpey's fibres. The pneumatized bones of several non-dinosaurian taxa do not exhibit the characteristics of this 'pneumosteum'. Our new histology-based approach thus can be instrumental in reconstructing the origin of air sacs among dinosaurs and hence for our understanding of this remarkable evolutionary novelty of the respiratory system.
Assuntos
Sacos Aéreos , Evolução Biológica , Osso e Ossos/anatomia & histologia , Dinossauros/anatomia & histologia , Dinossauros/classificação , Fósseis/anatomia & histologia , Sistema Respiratório/anatomia & histologia , Animais , Aves/anatomia & histologiaRESUMO
Carbapenems are now being explored for treatment of multidrug-resistant tuberculosis (MDR-TB), especially in conjunction with clavulanate. Clinical use is constrained by the need for multiple parenteral doses per day and the lack of knowledge of the optimal dose for sterilizing effect. Our objective was to identify the ertapenem exposure associated with optimal sterilizing effect and then design a once-a-day dose for clinical use. We utilized the hollow-fiber system model of tuberculosis in a 28-day exposure-response study of 8 different ertapenem doses in combination with clavulanate. The systems were sampled at predetermined time points to verify the concentration-time profile and identify the total bacterial burden. Inhibitory sigmoid maximum-effect (Emax) modeling was used to identify the relationship between total bacterial burden and the drug exposure and to identify optimal exposures. Contrary to the literature, ertapenem-clavulanate combination demonstrated good microbial kill and sterilizing effect. In a dose fractionation hollow-fiber study, efficacy was linked to percentage of the 24-h dosing interval of ertapenem concentration persisting above MIC (%TMIC). We performed 10,000 MDR-TB patient computer-aided clinical trial simulations, based on Monte Carlo methods, to identify the doses and schedule that would achieve or exceed a %TMIC of ≥40%. We identified an intravenous dosage of 2 g once per day as achieving the target in 96% of patients. An ertapenem susceptibility breakpoint MIC of 2 mg/liter was identified for that dose. An ertapenem dosage of 2 g once daily is the most suitable to be tested in a phase II study of sterilizing effect in MDR-TB patients.