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1.
Cell Mol Life Sci ; 81(1): 164, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575795

RESUMO

Diabetic hyperglycemia induces dysfunctions of arterial smooth muscle, leading to diabetic vascular complications. The CaV1.2 calcium channel is one primary pathway for Ca2+ influx, which initiates vasoconstriction. However, the long-term regulation mechanism(s) for vascular CaV1.2 functions under hyperglycemic condition remains unknown. Here, Sprague-Dawley rats fed with high-fat diet in combination with low dose streptozotocin and Goto-Kakizaki (GK) rats were used as diabetic models. Isolated mesenteric arteries (MAs) and vascular smooth muscle cells (VSMCs) from rat models were used to assess K+-induced arterial constriction and CaV1.2 channel functions using vascular myograph and whole-cell patch clamp, respectively. K+-induced vasoconstriction is persistently enhanced in the MAs from diabetic rats, and CaV1.2 alternative spliced exon 9* is increased, while exon 33 is decreased in rat diabetic arteries. Furthermore, CaV1.2 channels exhibit hyperpolarized current-voltage and activation curve in VSMCs from diabetic rats, which facilitates the channel function. Unexpectedly, the application of glycated serum (GS), mimicking advanced glycation end-products (AGEs), but not glucose, downregulates the expression of the splicing factor Rbfox1 in VSMCs. Moreover, GS application or Rbfox1 knockdown dynamically regulates alternative exons 9* and 33, leading to facilitated functions of CaV1.2 channels in VSMCs and MAs. Notably, GS increases K+-induced intracellular calcium concentration of VSMCs and the vasoconstriction of MAs. These results reveal that AGEs, not glucose, long-termly regulates CaV1.2 alternative splicing events by decreasing Rbfox1 expression, thereby enhancing channel functions and increasing vasoconstriction under diabetic hyperglycemia. This study identifies the specific molecular mechanism for enhanced vasoconstriction under hyperglycemia, providing a potential target for managing diabetic vascular complications.


Assuntos
Diabetes Mellitus Experimental , Angiopatias Diabéticas , Hiperglicemia , Animais , Ratos , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Constrição , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Angiopatias Diabéticas/metabolismo , Glucose/metabolismo , Hiperglicemia/genética , Hiperglicemia/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Ratos Sprague-Dawley
2.
Nat Microbiol ; 9(4): 1049-1063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480900

RESUMO

Bacterial cell division requires recruitment of peptidoglycan (PG) synthases to the division site by the tubulin homologue, FtsZ. Septal PG synthases promote septum growth. FtsZ treadmilling is proposed to drive the processive movement of septal PG synthases and septal constriction in some bacteria; however, the precise mechanisms spatio-temporally regulating PG synthase movement and activity and FtsZ treadmilling are poorly understood. Here using single-molecule imaging of division proteins in the Gram-positive pathogen Staphylococcus aureus, we showed that the septal PG synthase complex FtsW/PBP1 and its putative activator protein, DivIB, move with similar velocity around the division site. Impairing FtsZ treadmilling did not affect FtsW or DivIB velocities or septum constriction rates. Contrarily, PG synthesis inhibition decelerated or stopped directional movement of FtsW and DivIB, and septum constriction. Our findings suggest that a single population of processively moving FtsW/PBP1 associated with DivIB drives cell constriction independently of FtsZ treadmilling in S. aureus.


Assuntos
Proteínas de Bactérias , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Peptidoglicano/metabolismo , Constrição , Óxido Nítrico Sintase/metabolismo
3.
Trials ; 25(1): 164, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439024

RESUMO

BACKGROUND: Mortality, cerebral injury, and necrotizing enterocolitis (NEC) are common complications of very preterm birth. An important risk factor for these complications is hemodynamic instability. Pre-clinical studies suggest that the timing of umbilical cord clamping affects hemodynamic stability during transition. Standard care is time-based cord clamping (TBCC), with clamping irrespective of lung aeration. It is unknown whether delaying cord clamping until lung aeration and ventilation have been established (physiological-based cord clamping, PBCC) is more beneficial. This document describes the statistical analyses for the ABC3 trial, which aims to assess the efficacy and safety of PBCC, compared to TBCC. METHODS: The ABC3 trial is a multicenter, randomized trial investigating PBCC (intervention) versus TBCC (control) in very preterm infants. The trial is ethically approved. Preterm infants born before 30 weeks of gestation are randomized after parental informed consent. The primary outcome is intact survival, defined as the composite of survival without major cerebral injury and/or NEC. Secondary short-term outcomes are co-morbidities and adverse events assessed during NICU admission, parental reported outcomes, and long-term neurodevelopmental outcomes assessed at a corrected age of 2 years. To test the hypothesis that PBCC increases intact survival, a logistic regression model will be estimated using generalized estimating equations (accounting for correlation between siblings and observations in the same center) with treatment and gestational age as predictors. This plan is written and submitted without knowledge of the data. DISCUSSION: The findings of this trial will provide evidence for future clinical guidelines on optimal cord clamping management at birth. TRIAL REGISTRATION: ClinicalTrials.gov NCT03808051. Registered on 17 January 2019.


Assuntos
Recém-Nascido Prematuro , Nascimento Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Pré-Escolar , Constrição , Recém-Nascido de muito Baixo Peso , Respiração
4.
Braz J Cardiovasc Surg ; 39(2): e20230104, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426431

RESUMO

INTRODUCTION: Along with cardiopulmonary bypass time, aortic cross-clamping time is directly related to the risk of complications after heart surgery. The influence of the time difference between cardiopulmonary bypass and cross-clamping times (TDC-C) remains poorly understood. OBJECTIVE: To assess the impact of cardiopulmonary bypass time in relation to cross-clamping time on immediate results after coronary artery bypass grafting in the Registro Paulista de Cirurgia Cardiovascular (REPLICCAR) II. METHODS: Analysis of 3,090 patients included in REPLICCAR II database was performed. The Society of Thoracic Surgeons outcomes were evaluated (mortality, kidney failure, deep wound infection, reoperation, cerebrovascular accident, and prolonged ventilation time). A cutoff point was adopted, from which the increase of this difference would affect each outcome. RESULTS: After a cutoff point determination, all patients were divided into Group 1 (cardiopulmonary bypass time < 140 min., TDC-C < 30 min.), Group 2 (cardiopulmonary bypass time < 140 min., TDC-C > 30 min.), Group 3 (cardiopulmonary bypass time > 140 min., TDC-C < 30 min.), and Group 4 (cardiopulmonary bypass time > 140 min., TDC-C > 30 min.). After univariate logistic regression, Group 2 showed significant association with reoperation (odds ratio: 1.64, 95% confidence interval: 1.01-2.66), stroke (odds ratio: 3.85, 95% confidence interval: 1.99-7.63), kidney failure (odds ratio: 1.90, 95% confidence interval: 1.32-2.74), and in-hospital mortality (odds ratio: 2.17, 95% confidence interval: 1.30-3.60). CONCLUSION: TDC-C serves as a predictive factor for complications following coronary artery bypass grafting. We strongly recommend that future studies incorporate this metric to improve the prediction of complications.


Assuntos
Ponte Cardiopulmonar , Insuficiência Renal , Humanos , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/métodos , Constrição , Resultado do Tratamento , Ponte de Artéria Coronária/métodos , Insuficiência Renal/complicações , Fatores de Risco , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
5.
Elife ; 122024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512129

RESUMO

The SNARE proteins are central in membrane fusion and, at the synapse, neurotransmitter release. However, their involvement in the dual regulation of the synchronous release while maintaining a pool of readily releasable vesicles remains unclear. Using a chimeric approach, we performed a systematic analysis of the SNARE domain of STX1A by exchanging the whole SNARE domain or its N- or C-terminus subdomains with those of STX2. We expressed these chimeric constructs in STX1-null hippocampal mouse neurons. Exchanging the C-terminal half of STX1's SNARE domain with that of STX2 resulted in a reduced RRP accompanied by an increased release rate, while inserting the C-terminal half of STX1's SNARE domain into STX2 leads to an enhanced priming and decreased release rate. Additionally, we found that the mechanisms for clamping spontaneous, but not for Ca2+-evoked release, are particularly susceptible to changes in specific residues on the outer surface of the C-terminus of the SNARE domain of STX1A. Particularly, mutations of D231 and R232 affected the fusogenicity of the vesicles. We propose that the C-terminal half of the SNARE domain of STX1A plays a crucial role in the stabilization of the RRP as well as in the clamping of spontaneous synaptic vesicle fusion through the regulation of the energetic landscape for fusion, while it also plays a covert role in the speed and efficacy of Ca2+-evoked release.


Assuntos
Fusão de Membrana , Vesículas Sinápticas , Sintaxina 1 , Animais , Camundongos , Constrição , Camundongos Knockout , Neurotransmissores , Proteínas SNARE , Sintaxina 1/genética
6.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521995

RESUMO

In brightness, the pupil constricts, while in darkness, the pupil dilates; this is known as the pupillary light response (PLR). The PLR is driven by all photoreceptors: rods and cones, which contribute to image-forming vision, and intrinsically photosensitive retinal ganglion cells (ipRGCs), which mainly contribute to non-image-forming vision. Rods and cones cause immediate pupil constriction upon light exposure, whereas ipRGCs cause sustained constriction throughout light exposure. Recent studies have shown that covert attention modulated the initial PLR; however, it remains unclear whether the same holds for the sustained PLR. We tested this by leveraging ipRGCs' responsiveness to blue light, causing the most prominent sustained constriction. While replicating previous studies by showing that pupils constricted more when either directly looking at, or covertly attending to, bright as compared to dim stimuli (with the same color), we also found that the pupil constricted more when directly looking at blue as compared to red stimuli (with the same luminosity). Crucially, however, in two high-powered studies (n = 60), we did not find any pupil-size difference when covertly attending to blue as compared to red stimuli. This suggests that ipRGC-mediated pupil constriction, and possibly non-image-forming vision more generally, is not modulated by covert attention.


Assuntos
Células Ganglionares da Retina , Visão Ocular , Constrição , Células Ganglionares da Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Luz , Estimulação Luminosa
7.
Trials ; 25(1): 198, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509614

RESUMO

BACKGROUND: Infants born with congenital diaphragmatic hernia (CDH) are at high risk of respiratory insufficiency and pulmonary hypertension. Routine practice includes immediate clamping of the umbilical cord and endotracheal intubation. Experimental animal studies suggest that clamping the umbilical cord guided by physiological changes and after the lungs have been aerated, named physiological-based cord clamping (PBCC), could enhance the fetal-to-neonatal transition in CDH. We describe the statistical analysis plan for the clinical trial evaluating the effects of PBCC versus immediate cord clamping on pulmonary hypertension in infants with CDH (PinC trial). DESIGN: The PinC trial is a multicentre, randomised controlled trial in infants with isolated left-sided CDH, born ≥ 35.0 weeks of gestation. The primary outcome is the incidence of pulmonary hypertension in the first 24 h after birth. Maternal outcomes include estimated maternal blood loss. Neonatal secondary outcomes include mortality before discharge, extracorporeal membrane oxygenation therapy, and number of days of mechanical ventilation. Infants are 1:1 randomised to either PBCC or immediate cord clamping using variable random permutated block sizes (4-8), stratified by treatment centre and estimated severity of pulmonary hypoplasia (i.e. mild/moderate/severe). At least 140 infants are needed to detect a relative reduction in pulmonary hypertension by one third, with 80% power and 0.05 significance level. A chi-square test will be used to evaluate the hypothesis that PBCC decreases the occurrence of pulmonary hypertension. This plan is written and submitted without knowledge of the collected data. The trial has been ethically approved. TRIAL REGISTRATION: ClinicalTrials.gov NCT04373902 (registered April 2020).


Assuntos
Hérnias Diafragmáticas Congênitas , Hipertensão Pulmonar , Recém-Nascido , Gravidez , Animais , Feminino , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico , Clampeamento do Cordão Umbilical , Constrição , Respiração Artificial/efeitos adversos , Cordão Umbilical/cirurgia
8.
Function (Oxf) ; 5(2): zqae003, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486977

RESUMO

G protein regulation by regulators of G protein signaling (RGS) proteins play a key role in vascular tone maintenance. The loss of Gi/o and Gq/11 regulation by RGS2 and RGS5 in non-pregnant mice is implicated in augmented vascular tone and decreased uterine blood flow (UBF). RGS2 and 5 are closely related and co-expressed in uterine arteries (UA). However, whether and how RGS2 and 5 coordinate their regulatory activities to finetune G protein signaling and regulate vascular tone are unclear. Here, we determined how the integrated activity of RGS2 and 5 modulates vascular tone to promote UBF. Using ultrasonography and pressure myography, we examined uterine hemodynamics and myogenic tone (MT) of UA of wild type (WT), Rgs2-/-, Rgs5-/-, and Rgs2/5 dbKO mice. We found that MT was reduced in Rgs5-/- relative to WT or Rgs2-/- UA. Activating Gi/o with dopamine increased, whereas exogenous cAMP decreased MT in Rgs5-/- UA to levels in WT UA. Dual deletion of Rgs2 and 5 abolished the reduced MT due to the absence of Rgs5 and enhanced dopamine-induced Gi/o effects in Rgs2/5 dbKO UA. Conversely, and as in WT UA, Gi/o inhibition with pertussis toxin or exogenous cAMP decreased MT in Rgs2/5 dbKO to levels in Rgs5-/- UA. Inhibition of phosphodiesterases (PDE) concentration-dependently decreased and normalized MT in all genotypes, and blocked dopamine-induced MT augmentation in Rgs2-/-, Rgs5-/-, and Rgs2/5 dbKO UA. We conclude that Gi/o augments UA MT in the absence of RGS2 by a novel mechanism involving PDE-mediated inhibition of cAMP-dependent vasodilatation..


Assuntos
Dopamina , Transdução de Sinais , Camundongos , Animais , Constrição , Proteínas de Ligação ao GTP/metabolismo , Hemodinâmica
9.
Protein Sci ; 33(4): e4965, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38501596

RESUMO

The mechanosensitive channel of large conductance (MscL) acts as an "emergency release valve" that protects bacterial cells from acute hypoosmotic stress, and it serves as a paradigm for studying the mechanism underlying the transduction of mechanical forces. MscL gating is proposed to initiate with an expansion without opening, followed by subsequent pore opening via a number of intermediate substates, and ends in a full opening. However, the details of gating process are still largely unknown. Using in vivo viability assay, single channel patch clamp recording, cysteine cross-linking, and tryptophan fluorescence quenching approach, we identified and characterized MscL mutants with different occupancies of constriction region in the pore domain. The results demonstrated the shifts of constriction point along the gating pathway towards cytoplasic side from residue G26, though G22, to L19 upon gating, indicating the closed-expanded transitions coupling of the expansion of tightly packed hydrophobic constriction region to conduct the initial ion permeation in response to the membrane tension. Furthermore, these transitions were regulated by the hydrophobic and lipidic interaction with the constricting "hot spots". Our data reveal a new resolution of the transitions from the closed to the opening substate of MscL, providing insights into the gating mechanisms of MscL.


Assuntos
Proteínas de Escherichia coli , Canais Iônicos , Canais Iônicos/genética , Canais Iônicos/química , Canais Iônicos/metabolismo , Ativação do Canal Iônico/fisiologia , Proteínas de Escherichia coli/química , Constrição
10.
J Vis Exp ; (205)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38526120

RESUMO

Animal models remain necessary tools to study neuropathic pain. This manuscript describes the distal infraorbital nerve chronic constriction injury (DIoN-CCI) model to study trigeminal neuropathic pain in mice. This includes the surgical procedures to perform the chronic constriction injury and the postoperative behavioral tests to evaluate the changes in spontaneous and evoked behavior that are signs of ongoing pain and mechanical allodynia. The methods and behavioral readouts are similar to the infraorbital nerve chronic constriction injury (IoN-CCI) model in rats. However, important changes are necessary for the adaptation of the IoN-CCI model to mice. First, the intra-orbital approach is replaced by a more rostral approach with an incision between the eye and the whisker pad. The IoN is thus ligated distally outside the orbital cavity. Secondly, due to the higher locomotor activity in mice, allowing rats to move freely in small cages is replaced by placing mice in custom-designed and constructed restraining devices. After DIoN ligation, mice exhibit changes in spontaneous behavior and in response to von Frey hair stimulation that are similar to those in IoN-CCI rats, i.e., increased directed face grooming and hyperresponsiveness to von Frey hair stimulation of the IoN territory.


Assuntos
Neuralgia , Neuralgia do Trigêmeo , Ratos , Camundongos , Animais , Constrição , Ratos Sprague-Dawley , Neuralgia do Trigêmeo/cirurgia , Nervo Maxilar/lesões , Neuralgia/etiologia , Hiperalgesia/etiologia , Modelos Animais de Doenças , Nervo Trigêmeo
11.
J Neuroinflammation ; 21(1): 60, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419042

RESUMO

BACKGROUND: The spinal inflammatory signal often spreads to distant segments, accompanied by widespread pain symptom under neuropathological conditions. Multiple cytokines are released into the cerebrospinal fluid (CSF), potentially inducing the activation of an inflammatory cascade at remote segments through CSF flow. However, the detailed alteration of CSF in neuropathic pain and its specific role in widespread pain remain obscure. METHODS: A chronic constriction injury of the infraorbital nerve (CCI-ION) model was constructed, and pain-related behavior was observed on the 7th, 14th, 21st, and 28th days post surgery, in both vibrissa pads and hind paws. CSF from CCI-ION rats was transplanted to naïve rats through intracisternal injection, and thermal and mechanical allodynia were measured in hind paws. The alteration of inflammatory cytokines in CCI-ION's CSF was detected using an antibody array and bioinformatic analysis. Pharmacological intervention targeting the changed cytokine in the CSF and downstream signaling was performed to evaluate its role in widespread pain. RESULTS: CCI-ION induced local pain in vibrissa pads together with widespread pain in hind paws. CCI-ION's CSF transplantation, compared with sham CSF, contributed to vibrissa pad pain and hind paw pain in recipient rats. Among the measured cytokines, interleukin-6 (IL-6) and leptin were increased in CCI-ION's CSF, while interleukin-13 (IL-13) was significantly reduced. Furthermore, the concentration of CSF IL-6 was correlated with nerve injury extent, which gated the occurrence of widespread pain. Both astrocytes and microglia were increased in remote segments of the CCI-ION model, while the inhibition of astrocytes in remote segments, but not microglia, significantly alleviated widespread pain. Mechanically, astroglial signal transducer and activator of transcription 3 (STAT3) in remote segments were activated by CSF IL-6, the inhibition of which significantly mitigated widespread pain in CCI-ION. CONCLUSION: IL-6 was induced in the CSF of the CCI-ION model, triggering widespread pain via activating astrocyte STAT3 signal in remote segments. Therapies targeting IL-6/STAT3 signaling might serve as a promising strategy for the widespread pain symptom under neuropathological conditions.


Assuntos
Interleucina-6 , Neuralgia , Ratos , Animais , Interleucina-6/metabolismo , Ratos Sprague-Dawley , Fator de Transcrição STAT3/metabolismo , Gliose/complicações , Constrição , Hiperalgesia/etiologia , Hiperalgesia/tratamento farmacológico , Neuralgia/tratamento farmacológico , Citocinas
12.
J Neuroinflammation ; 21(1): 57, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388415

RESUMO

BACKGROUND: Neuropathic pain (NP) is a kind of intractable pain. The pathogenesis of NP remains a complicated issue for pain management practitioners. SPARC/osteonectin, CWCV, and Kazal-like domains proteoglycan 2 (SPOCK2) are members of the SPOCK family that play a significant role in the development of the central nervous system. In this study, we investigated the role of SPOCK2 in the development of NP in a rat model of chronic constriction injury (CCI). METHODS: Sprague-Dawley rats were randomly grouped to establish CCI models. We examined the effects of SPOCK2 on pain hpersensitivity and spinal astrocyte activation after CCI-induced NP. Paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were used to reflects the pain behavioral degree. Molecular mechanisms involved in SPOCK2-mediated NP in vivo were examined by western blot analysis, immunofluorescence, immunohistochemistry, and co-immunoprecipitation. In addition, we examined the SPOCK2-mediated potential protein-protein interaction (PPI) in vitro coimmunoprecipitation (Co-IP) experiments. RESULTS: We founded the expression level of SPOCK2 in rat spinal cord was markedly increased after CCI-induced NP, while SPOCK2 downregulation could partially relieve pain caused by CCI. Our research showed that SPOCK2 expressed significantly increase in spinal astrocytes when CCI-induced NP. In addition, SPOCK2 could act as an upstream signaling molecule to regulate the activation of matrix metalloproteinase-2 (MMP-2), thus affecting astrocytic ERK1/2 activation and interleukin (IL)-1ß production in the development of NP. Moreover, in vitro coimmunoprecipitation (Co-IP) experiments showed that SPOCK2 could interact with membrane-type 1 matrix metalloproteinase (MT1-MMP/MMP14) to regulate MMP-2 activation by the SPARC extracellular (SPARC_EC) domain. CONCLUSIONS: Research shows that SPOCK2 can interact with MT1-MMP to regulate MMP-2 activation, thus affecting astrocytic ERK1/2 activation and IL-1ß production to achieve positive promotion of NP.


Assuntos
Astrócitos , Neuralgia , Animais , Ratos , Astrócitos/metabolismo , Constrição , Metaloproteinase 14 da Matriz , Metaloproteinase 2 da Matriz , Neuralgia/etiologia , Neuralgia/metabolismo , Ratos Sprague-Dawley
13.
Dig Dis Sci ; 69(3): 961-968, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340259

RESUMO

BACKGROUND: External biliary fistula, where the residual cyst is associated with the biliary tree, is one of the most common complications after liver hydatid cyst surgery. Surgical procedures become a consideration for patients in whom the biliary fistula persists despite all endoscopic procedures. However, reoperation for biliary fistula after hydatid cyst surgery leads to additional complications and increases morbidity and mortality. AIM: This study aims to treat persistent biliary fistulas that develop after liver hydatid cyst surgery using a simple noninvasive technique. MATERIALS AND METHODS: External drainage surgery was performed on 295 patients with liver hydatid cysts. Endoscopic treatment methods were used in patients who developed biliary fistula after surgery. Despite all endoscopic treatment methods, 14 patients developed persistent biliary fistulas. These patients were subsequently treated using the drain clamping technique. FINDINGS: All persistent fistulas occluded in 11.86 days (with a range of 8-20 days). No complications were observed in the one-year follow-up visits. CONCLUSION: Drain clamping, a novel approach to the treatment of persistent biliary fistulas developed despite all available endoscopic methods, can be safely used. This technique resulted in a complete recovery in patients without the need for surgical procedures.


Assuntos
Fístula Biliar , Equinococose Hepática , Humanos , Fístula Biliar/etiologia , Fístula Biliar/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Constrição , Equinococose Hepática/cirurgia , Equinococose Hepática/complicações , Drenagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
14.
Sci Rep ; 14(1): 2030, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263346

RESUMO

The development and characterization of a new enzyme reaction contribute to advancements in modern biotechnology. Here, we report a novel CIS (clamping-mediated incorporation of single-stranded DNA with concomitant DNA synthesis) reaction catalyzed by Taq polymerase. In the reaction, a single-stranded DNA (ssDNA) with 3' Cs is attached with a preformed 3' G-tail of double-stranded DNA (dsDNA); DNA syntheses starting from both 3' ends result in the incorporation of ssDNA. A 3' G-tail length of 3 nucleotides adequately supports this reaction, indicating that Taq polymerase can clump short Watson-Crick base pairs as short as three pairs and use them to initiate DNA polymerization. The reverse transcriptase from Molony murine leukemia virus catalyzes strand displacement synthesis and produces flapped-end DNA, whereas the reaction by Taq polymerase involves the nick translation. These new reaction properties may be beneficial for the development of new molecular tools applicable in various fields. Apart from its CIS reaction activity, we also report that Taq polymerase has the undesirable characteristic of removing 5' fluorescent labels from dsDNA. This characteristic may have compromised various experiments involving the preparation of fluorescently-labeled dsDNA by PCR for a long time.


Assuntos
Replicação do DNA , DNA de Cadeia Simples , Camundongos , Animais , Taq Polimerase , Constrição , Biotecnologia
15.
Nephrology (Carlton) ; 29(4): 188-200, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38173056

RESUMO

AIM: In two recent studies, we observed that a 30-min renal vein clamping caused formation of interstitial haemorrhagic congestion in ischaemic and ischaemic/reperfused kidney along with the development of severer acute kidney injury (AKI) than renal artery or pedicle clamping. It was suggested that the transmission of high arterial pressure into renal microvessels during vein occlusion probably causes the occurrence of interstitial haemorrhagic congestion that augments AKI. The present investigation aimed to evaluate this suggestion by reducing renal perfusion pressure (RPP) during renal venous occlusion. METHODS: Anaesthetized male Sprague-Dawley rats were divided into three groups (n = 8), which underwent a 2-h reperfusion period following 30-min bilateral renal venous clamping along with reduced RPP (VIR-rRPP group) or without reduced RPP (VIR group) and an equivalent period after sham-operation (Sham group). RESULTS: The VIR-rRPP group compared with VIR group had lower levels of kidney malondialdehyde and tissue damages as epithelial injuries of proximal tubule and thick ascending limb, vascular congestion, intratubular cast and oedema, along with the less reductions in renal blood flow, creatinine clearance, Na+ -reabsorption, K+ and urea excretion, urine osmolality and free-water reabsorption. Importantly, the formation of intensive interstitial haemorrhagic congestion in the VIR group was not observed in the VIR-rRPP group. CONCLUSION: These results indicate that the transmission of high arterial pressure into renal microvessels during venous occlusion leads to rupturing of their walls and the formation of interstitial haemorrhagic congestion, which has an augmenting impact on ischaemia/reperfusion-induced renal structural damages and haemodynamic, excretory and urine-concentrating dysfunctions.


Assuntos
Injúria Renal Aguda , Hipertensão , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Pressão Arterial , Constrição , Ratos Sprague-Dawley , Rim , Injúria Renal Aguda/etiologia , Traumatismo por Reperfusão/complicações , Isquemia/complicações , Reperfusão/efeitos adversos , Microvasos
16.
Acta Paediatr ; 113(5): 931-938, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38293717

RESUMO

AIM: We investigated the influence of physiological-based cord clamping (PBCC) on cardiorespiratory stability in very low birth weight (VLBW) infants during the first 72 h of life. METHODS: This retrospective study comprised VLBW infants born at <32 + 0 weeks of gestation and admitted to the neonatal intensive care unit of the Medical University of Graz, Austria, from December 2014 to April 2021. VLBW infants delivered with PBCC were matched by gestational age and birth weight to delayed cord clamping controls. The PBCC group was stabilised after birth with an intact cord. Routine monitoring parameters were compared between the groups. RESULTS: We included 54 VLBW infants. The mean gestational ages of the PBCC group and controls were 27.4 ± 1.9 versus 27.4 ± 1.8 weeks (p = 0.87), and the mean birth weights were 912 ± 288 versus 915 ± 285 g (p = 0.96), respectively. The mean cord clamping time was 191 ± 78 s in the PBCC group. Heart rate was lower in the PBCC group during the first 3 days after birth, reaching significance by 10 h. Other monitoring parameters did not reveal any differences between the two groups. CONCLUSION: PBCC stabilised cardiorespiratory parameters in VLBW infants. The lower heart rate in the PBCC group suggested higher blood volume following intact cord resuscitation.


Assuntos
Recém-Nascido de muito Baixo Peso , Cordão Umbilical , Recém-Nascido , Lactente , Humanos , Constrição , Estudos Retrospectivos , Peso ao Nascer , Idade Gestacional , Cordão Umbilical/fisiologia
17.
PLoS One ; 19(1): e0295929, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38165946

RESUMO

BACKGROUND: Delayed cord clamping (DCC) is a proven beneficial intervention, but the suggested timings of DCC vary from 30 to 300 seconds after birth or until cord pulsation stops. This study aimed to find the optimum timing of DCC to maximize the benefits such as an increase in hemoglobin, and hematocrit without increasing the risks of polycythemia and hyperbilirubinemia. METHODS: We conducted a single-center prospective observational cohort study. All singleton neonates with gestational age ≥ 28 weeks born at the center in the 17 months of the study period from November 2020 to March 2022 were enrolled. Participants were divided into four groups based on DCC time: group A: <60 sec, group B: 60-119 sec, group C: 120-180 sec, and group D: >180 sec. The primary outcome was the levels of hemoglobin, hematocrit, and bilirubin at 48 hours of life. RESULTS: Four hundred and eight neonates were enrolled. They were divided into four groups based on the timing of DCC (group A: n = 52, group B: n = 137, group C: n = 155, group D: n = 64). With an increase in the duration of DCC, there was an increase in the level of hemoglobin and hematocrit without an increase in the risk of polycythemia or neonatal hyperbilirubinemia. The benefits were best in group C (120-180 sec) and group D (>180 sec). CONCLUSIONS: DCC of ≥ 120 seconds appears to be optimal where hemoglobin and hematocrit are highest without an increase in the risk of neonatal hyperbilirubinemia. The risk of adverse effects like polycythemia or neonatal hyperbilirubinemia requiring phototherapy did not increase even after extending the time of cord clamping to >180 seconds.


Assuntos
Hiperbilirrubinemia Neonatal , Policitemia , Recém-Nascido , Lactente , Humanos , Constrição , Estudos Prospectivos , Hemoglobinas , Bilirrubina , Cordão Umbilical
18.
ACS Biomater Sci Eng ; 10(2): 987-997, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38234159

RESUMO

A combination of human-induced pluripotent stem cells (hiPSCs) and 3D microtissue culture techniques allows the generation of models that recapitulate the cardiac microenvironment for preclinical research of new treatments. In particular, spheroids represent the simplest approach to culture cells in 3D and generate gradients of cellular access to the media, mimicking the effects of an ischemic event. However, previous models required incubation under low oxygen conditions or deprived nutrient media to recreate ischemia. Here, we describe the generation of large spheroids (i.e., larger than 500 µm diameter) that self-induce an ischemic core. Spheroids were generated by coculture of cardiomyocytes derived from hiPSCs (hiPSC-CMs) and primary human cardiac fibroblast (hCF). In the proper medium, cells formed aggregates that generated an ischemic core 2 days after seeding. Spheroids also showed spontaneous cellular reorganization after 10 days, with hiPSC-CMs located at the center and surrounded by hCFs. This led to an increase in microtissue stiffness, characterized by the implementation of a constriction assay. All in all, these phenomena are hints of the fibrotic tissue remodeling secondary to a cardiac ischemic event, thus demonstrating the suitability of these spheroids for the modeling of human cardiac ischemia and its potential application for new treatments and drug research.


Assuntos
Isquemia Miocárdica , Miócitos Cardíacos , Humanos , Constrição , Células Cultivadas , Isquemia
19.
Early Hum Dev ; 189: 105928, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211436

RESUMO

OBJECTIVES: Neonatal trials have traditionally used binary composite short-term (such as death or bronchopulmonary dysplasia) or longer-term (such as death or severe neurodevelopmental impairment) outcomes. We applied the Desirability Of Outcome Ranking (DOOR) method to rank the overall patient outcome by best (no morbidities) to worst (death). STUDY DESIGN: Using a completed large multicenter trial (Milking In Non-Vigorous Infants [MINVI]) of umbilical cord milking (UCM) vs. early cord clamping (ECC), we applied the DOOR methodology to neonatal outcomes. Six outcomes were chosen and ranked: no interventions or NICU admission (most desirable); received initial cardiorespiratory support at birth; neonatal intensive care unit (NICU) admission for predefined criteria; mild hypoxic-ischemic encephalopathy (HIE); moderate to severe HIE; and death (least desirable). RESULTS: 1524 non-vigorous newborns born between 35 and 42 weeks' gestation had data for analysis. The DOOR distribution was different between the UCM and ECC arms, with a significantly greater probability (55.8 % [95 % CI 53.1-58.5 %; p < 0.0001]) of a randomly selected neonate having a more desirable outcome if they were in the UCM arm. DOOR probabilities of averting individual adverse outcomes such as NICU admission for predefined criteria (52.8 %; 95%CI 50.5-55.1 %) and cardiorespiratory support (54.0 %; 95%CI 51.6-56.4 %) were significantly higher among those in the UCM group. CONCLUSION: DOOR provides an overall assessment of the benefits and harms with greater insight than typical binary composite measures to clinicians and parents when evaluating an intervention. Future neonatal trials should consider the a priori use of the DOOR methodology to evaluate trial outcomes.


Assuntos
Recém-Nascido Prematuro , Cordão Umbilical , Humanos , Recém-Nascido , Lactente , Idade Gestacional , Constrição
20.
Arch Gynecol Obstet ; 309(1): 47-62, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36988681

RESUMO

OBJECTIVE: This narrative review was performed to evaluate the correct timing of umbilical cord clamping for term infants. It was intended to determine any advantages or disadvantages from early or delayed cord clamping for newborns, infants or mothers. METHODS: A systematic search on two databases was conducted using the PICO pattern to define a wide search. Out of 43 trials, 12 were included in this review. Three of the included studies are meta-analyses, nine are randomized controlled trials. RESULTS: Early or delayed cord clamping was defined differently in all the included trials. However, there are many advantages from delayed cord clamping of at least > 60 s for newborns and infants up to 12 months of age. The trials showed no disadvantages for newborns or mothers from delayed cord clamping, except for a lightly increased risk of jaundice or the need for phototherapy. CONCLUSION: Delayed umbilical cord clamping for term infants should be performed. Further research is needed to improve knowledge on physiological timing of umbilical cord clamping in term infants, which also leads to the same advantages as delayed cord clamping.


Assuntos
Mães , Clampeamento do Cordão Umbilical , Gravidez , Lactente , Feminino , Recém-Nascido , Humanos , Cordão Umbilical/cirurgia , Fatores de Tempo , Constrição
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