BACKGROUND: Advancing the retrograde microcatheter (MC) into the antegrade guide catheter during retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can be challenging or impossible, preventing guidewire externalization. OBJECTIVES: To detail and evaluate all the techniques focused on wiring to achieve intubation of the distal tip of a microcatheter, balloon, or stent with an antegrade or retrograde guidewire, aiming to reduce complications by minimizing tension on fragile collaterals during externalization and enabling rapid antegrade conversion in various clinical scenarios. METHODS: We describe the two main techniques, tip-in and rendezvous, and their derivatives such a facilitated tip-in, manual MC-tip modification, tip-in the balloon, tip-in the stent, deep dive rendezvous, catch-it and antegrade microcatheter probing. We provide case studies that demonstrate the effectiveness of these techniques in complex scenarios involving extreme vessel angulation, severe calcification, fragile collaterals, and challenging retrograde MC crossing without externalization. CONCLUSION: The development of advanced variants along with traditional techniques to establish retrograde guidewire connection and antegrade conversion has led to the establishment of a cohesive group of methods known as portal techniques. These approaches serve as strategic advantages in retrograde CTO-PCI, providing a valuable and feasible alternative to conventional retrograde connection techniques, particularly when those techniques fail. Their ability to avoid the externalization process reduces potential damage to collateral channels and the ostium of the donor artery, potentially leading to a reduction in complication rates.
- MeSH
- Angioplasty, Balloon, Coronary instrumentation adverse effects MeSH
- Chronic Disease MeSH
- Equipment Design MeSH
- Percutaneous Coronary Intervention instrumentation adverse effects MeSH
- Coronary Occlusion * diagnostic imaging therapy physiopathology MeSH
- Humans MeSH
- Miniaturization MeSH
- Cardiac Catheters * MeSH
- Stents * MeSH
- Treatment Outcome MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Androgenní alopecie je nejčastější příčinou vypadávání vlasů u mužů i žen. Tento stav je způsoben genetickými predispozicemi a vlivem androgenů, zejména dihydrotestosteronu (DHT), který negativně ovlivňuje vlasové folikuly a vede k jejich postupné miniaturizaci. Mezi běžné léčebné možnosti patří farmakologická terapie (např. finasterid nebo minoxidil) a chirurgické metody, jako je transplantace vlasů. Novou a slibnou metodou je autologní transplantace progenitorových buněk, která představuje miniinvazivní zákrok využívající regenerační schopnosti vlastních buněk pacienta. Tento přístup může významně podpořit obnovu vlasových folikulů, zlepšit kvalitu vlasů a oddálit další progresi onemocnění, a to s minimálním rizikem vedlejších účinků.
Androgenetic alopecia is the most common cause of hair loss in both men and women. This condition results from genetic predispositions and the influence of androgens, particularly dihydrotestosterone (DHT), which adversely affects hair follicles and leads to their gradual miniaturization. Conventional treatment options include pharmacological therapy (e.g., finasteride or minoxidil) and surgical methods such as hair transplantation. A novel and promising approach is autologous progenitor cell transplantation, a minimally invasive procedure that utilizes the regenerative potential of the patient's own cells. This method has the potential to significantly enhance hair follicle regeneration, improve hair quality, and delay further progression of the condition, all while minimizing the risk of adverse effects.
- MeSH
- Alopecia * diagnosis etiology drug therapy MeSH
- Transplantation, Autologous methods MeSH
- Dihydrotestosterone metabolism MeSH
- Adult MeSH
- Case Reports as Topic MeSH
- Humans MeSH
- Stem Cell Transplantation * methods MeSH
- Hair Follicle pathology MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Review MeSH
Článek popisuje případ štěněte pomeraniana, které utrpělo zlomeninu kostí levého antebrachia. Malá a miniaturní plemena psů jsou ke vzniku zlomenin antebrachia predisponována. Díky anatomickým a biomechanickým specifikům je nutno přistupovat k řešení těchto traumat odlišně než u jiných zlomenin. Článek představuje použití orthogonal plating u konkrétního pacienta a snaží se objasnit filozofii této metody.
The article describes a case of a Pomeranian puppy that suffered a fracture of the left antebrachium. Toy and miniature breeds of dogs are predisposed to antebrachial fractures. Due to some anatomical and biomechanical specifics, it is necessary to approach these traumas differently than other fractures. The article presents the use of orthogonal plating in a specific patient and tries to clarify the philosophy of this method.
- MeSH
- Arm Bones * injuries MeSH
- Animal Diseases MeSH
- Dogs MeSH
- Fracture Fixation, Internal * veterinary MeSH
- Animals MeSH
- Check Tag
- Dogs MeSH
- Animals MeSH
- Publication type
- Case Reports MeSH
Single-photon optogenetics enables precise, cell-type-specific modulation of neuronal circuits, making it a crucial tool in neuroscience. Its miniaturization in the form of fully implantable wide-field stimulator arrays enables long-term interrogation of cortical circuits and bears promise for brain-machine interfaces for sensory and motor function restoration. However, achieving selective activation of functional cortical representations poses a challenge, as studies show that targeted optogenetic stimulation results in activity spread beyond one functional domain. While recurrent network mechanisms contribute to activity spread, here we demonstrate with detailed simulations of isolated pyramidal neurons from cats of unknown sex that already neuron morphology causes a complex spread of optogenetic activity at the scale of one cortical column. Since the shape of a neuron impacts its optogenetic response, we find that a single stimulator at the cortical surface recruits a complex spatial distribution of neurons that can be inhomogeneous and vary with stimulation intensity and neuronal morphology across layers. We explore strategies to enhance stimulation precision, finding that optimizing stimulator optics may offer more significant improvements than the preferentially somatic expression of the opsin through genetic targeting. Our results indicate that, with the right optical setup, single-photon optogenetics can precisely activate isolated neurons at the scale of functional cortical domains spanning several hundred micrometers.
- MeSH
- Cats MeSH
- Models, Neurological MeSH
- Cerebral Cortex physiology cytology MeSH
- Neurons physiology MeSH
- Optogenetics * methods MeSH
- Pyramidal Cells physiology MeSH
- Photic Stimulation methods MeSH
- Animals MeSH
- Check Tag
- Cats MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
The retrograde approach in chronic total occlusion (CTO) interventions often encounters significant challenges, particularly, when aligning the retrograde microcatheter (MC) with the antegrade system is difficult, complicating or even preventing standard externalization. To address these issues, techniques like the "tip-in" have proven to be effective backup strategies. We introduce the "Manual Microcatheter-tip Modification" (MMM) technique as an alternative when the "tip-in" method faces complications. We present a case of a left anterior descending CTO where MMM was successfully employed for the first time, enabling successful revascularization by manually modifying the MC tip to engage the retrograde guidewire. We explore the technical details within the framework of contemporary CTO PCI. This new technique could enhance the management of CTO interventions, offering innovative solutions when traditional externalization methods are problematic.
- MeSH
- Angioplasty, Balloon, Coronary instrumentation MeSH
- Chronic Disease MeSH
- Equipment Design * MeSH
- Coronary Angiography * MeSH
- Percutaneous Coronary Intervention instrumentation MeSH
- Coronary Occlusion * diagnostic imaging therapy MeSH
- Middle Aged MeSH
- Humans MeSH
- Miniaturization * MeSH
- Aged MeSH
- Cardiac Catheterization instrumentation MeSH
- Cardiac Catheters * MeSH
- Treatment Outcome MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
PURPOSE: To assess the safety and feasibility of direct vitrectomy-sparing subretinal injection for gene delivery in a large animal model. METHODS: The experimental Liběchov minipigs were used for subretinal delivery of a plasmid DNA vector (pS/MAR-CMV-copGFP) with cytomegalovirus (CMV) promoter, green fluorescent protein (GFP) reporter (copGFP) and a scaffold/matrix attachment region (S/MAR) sequence. The eyes were randomized to subretinal injection of the vector following pars plana vitrectomy (control group) or a direct injection without prior vitrectomy surgery (experimental group). Intra- and post-operative observations up to 30 days after surgery were compared. RESULTS: Six eyes of three mini-pigs underwent surgery for delivery into the subretinal space. Two eyes in the control group were operated with a classical approach (lens-sparing vitrectomy and posterior hyaloid detachment). The other four eyes in the experimental group were injected directly with a subretinal cannula without vitrectomy surgery. No adverse events, such as endophthalmitis, retinal detachment and intraocular pressure elevation were observed post-operatively. The eyes in the experimental group had both shorter surgical time and recovery while achieving the same surgical goal. CONCLUSIONS: This pilot study demonstrates that successful subretinal delivery of gene therapy vectors is achievable using a direct injection without prior vitrectomy surgery.
- MeSH
- Genetic Therapy * methods MeSH
- Genetic Vectors * administration & dosage MeSH
- Injections, Intraocular MeSH
- Swine, Miniature * MeSH
- Disease Models, Animal MeSH
- Pilot Projects MeSH
- Plasmids administration & dosage MeSH
- Swine MeSH
- Retina MeSH
- Feasibility Studies * MeSH
- Gene Transfer Techniques * MeSH
- Vitrectomy * methods MeSH
- Green Fluorescent Proteins genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Anandamide (AEA) is an important modulator of nociception in the spinal dorsal horn, acting presynaptically through Cannabinoid (CB1) and Transient receptor potential vanilloid (TRPV1) receptors. The role of AEA (1 μM, 10 μM, and 30 μM) application on the modulation of nociceptive synaptic transmission under control and inflammatory conditions was studied by recording miniature excitatory postsynaptic currents (mEPSCs) from neurons in spinal cord slices. Inhibition of the CB1 receptors by PF514273, TRPV1 by SB366791, and the fatty acid amide hydrolase (FAAH) by URB597 was used. Under naïve conditions, the AEA application did not affect the mEPSCs frequency (1.43±0.12 Hz) when all the recorded neurons were considered. The mEPSC frequency increased (180.0±39.2%) only when AEA (30 μM) was applied with PF514273 and URB597. Analysis showed that one sub-population of neurons had synaptic input inhibited (39.1% of neurons), the second excited (43.5%), whereas 8.7% showed a mixed effect and 8.7% did not respond to the AEA. With inflammation, the AEA effect was highly inhibitory (72.7%), while the excitation was negligible (9.1%), and 18.2% were not modulated. After inflammation, more neurons (45.0%) responded even to low AEA by mEPSC frequency increase with PF514273/URB597 present. AEA-induced dual (excitatory/inhibitory) effects at the 1st nociceptive synapse should be considered when developing analgesics targeting the endocannabinoid system. These findings contrast the clear inhibitory effects of the AEA precursor 20:4-NAPE application described previously and suggest that modulation of endogenous AEA production may be more favorable for analgesic treatments.
- MeSH
- Amidohydrolases MeSH
- Analgesics pharmacology MeSH
- Benzamides * MeSH
- Endocannabinoids * pharmacology MeSH
- Carbamates * MeSH
- Arachidonic Acids * MeSH
- Humans MeSH
- Nociception * MeSH
- Polyunsaturated Alkamides pharmacology MeSH
- Spinal Cord Dorsal Horn MeSH
- Inflammation drug therapy MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
We applied Raman spectroscopy to brain and skin tissues from a minipig model of Huntington's disease. Differences were observed between measured spectra of tissues with and without Huntington's disease, for both brain tissue and skin tissue. There are linked to changes in the chemical composition between tissue types. Using machine learning we correctly classified 96% of test spectra as diseased or wild type, indicating that the test would have a similar accuracy when used as a diagnostic tool for the disease. This suggests the technique has great potential in the rapid and accurate diagnosis of Huntington's and other neurodegenerative diseases in a clinical setting.
- MeSH
- Huntington Disease * diagnosis MeSH
- Humans MeSH
- Swine, Miniature MeSH
- Brain MeSH
- Neurodegenerative Diseases * MeSH
- Swine MeSH
- Spectrum Analysis, Raman MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: The availability of dialysis membranes in the form of hollow fibres with diameters compatible with the fused silica capillaries used in capillary electrophoresis is very limited. However, haemodialysis bicarbonate cartridges commonly used in human medicine containing polysulfone hollow fibres are available on the market and are used for the fabrication of coaxial microdialysis probes. The miniature probe design ensures that steady-state conditions are achieved during microdialysis of minimal volumes of body fluids. RESULTS: A coaxial microdialysis probe with a length of 5 cm and an inner diameter of 200 μm is used for microdialysis of 10 μL of body fluid collected into a sampling fused silica capillary with an inner diameter 430 μm. Microdialysis is performed into 0.01 M HCl as a perfusate at stopped flow and 2 μL of the resulting microdialysate are subjected to analysis by capillary electrophoresis with contactless conductivity detection. Microdialysis pre-treatment is verified by analysis of 11 common amino acids at a 100 μM concentration level, resulting in recoveries of 98.3-102.5%. The electrophoretic separation of amino acids is performed in 8.5 M acetic acid at pH 1.37 as a background electrolyte with analysis time up to 4.5 min and LOD in the range of 0.12-0.28 μM. The reproducibility of the developed technique determined for the peak area ranges from 1.2 to 4.5%. Applicability is tested in the quantification of valine and leucine in plasma during fasting and subsequent reconvalescence. SIGNIFICANCE: The fabrication of a coaxial microdialysis probe for the laboratory preparation of microliter volumes of various types of clinical samples is described, which is coupled off-line with capillary electrophoretic monitoring of amino acids in 2 μL volumes of microdialysate. The developed methodology is suitable for quantification of 20 amino acids in whole human blood, plasma, tears and has potential for analysis of dry blood spots captured on hollow fibre.
- MeSH
- Amino Acids * MeSH
- Electrophoresis, Capillary MeSH
- Humans MeSH
- Microdialysis MeSH
- Silicon Dioxide MeSH
- Reproducibility of Results MeSH
- Body Fluids * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
