Rapid cleavage of IL-1ß in DRG neurons produces tissue injury-induced pain hypersensitivity.

Background: IL-1ß plays a critical role in the pathophysiology of neuroinflammation. The presence of cleaved IL-1ß (cIL-1ß) in the neurons of the dorsal root ganglion (DRG) implicates its function in biological signaling arising from the sensory neuron. This study was conducted to analyze the role of IL-1ß in nociceptive transduction after tissue injury. Methods: A plantar incision was made in C57BL/6 mice, following which immunohistochemistry and RNA scope in situ hybridization were performed at various time points to analyze cIL-1ß, caspase-1, and IL-1 receptor 1 (IL-1R1) expression in the DRG. The effect of intrathecal administration of a caspase-1 inhibitor or regional anesthesia using local anesthetics on cIL-1ß expression and pain hypersensitivity was analyzed by immunohistochemistry and behavioral analysis. ERK phosphorylation was also analyzed to investigate the effect of IL-1ß on the activity of spinal dorsal horn neurons. Results: cIL-1ß expression was significantly increased in caspase-1-positive DRG neurons 5 min after the plantar incision. Intrathecal caspase-1 inhibitor treatment inhibited IL-1ß cleavage and pain hypersensitivity after the plantar incision. IL-1R1 was also detected in the DRG neurons, although the majority of IL-1R1-expressing neurons lacked cIL-1ß expression. Regional anesthesia using local anesthetics prevented cIL-1ß processing. Plantar incision-induced phosphorylation of ERK was inhibited by the caspase-1 inhibitor. Conclusion: IL-1ß in the DRG neuron undergoes rapid cleavage in response to tissue injury in an activity-dependent manner. Cleaved IL-1ß causes injury-induced functional activation of sensory neurons and pain hypersensitivity. IL-1ß in the primary afferent neurons is involved in physiological nociceptive signal transduction.

Epicardial pacing lead implantation for congenital complete atrioventricular block immediately after birth: a case report.

BACKGROUND: The incidence of congenital complete atrioventricular block is estimated to be 1 per 20,000 deliveries. In the fetal period, the fetal mortality rate is high, but the treatment strategy has not yet been established. In severe cases, early postnatal pacing therapy is necessary. CASE PRESENTATION: A 0-day-old Japanese baby girl was diagnosed with fetal congenital complete atrioventricular block during a prenatal physical examination. A joint conference was held preoperatively among multidisciplinary departments, and a cesarean section was performed at 37 weeks pregnancy, immediately followed by scheduled internal ventricular pacing lead implantation in an adjacent room. Percutaneous pacing was ineffective. The epicardial pacing lead was sutured at 17.5 minutes after birth, and perioperative management was successful with a heart rate and pulse rate of 150 beats per minute. CONCLUSION: The infant with a congenital complete atrioventricular block was rescued by an uneventful epicardial lead implantation.

Synthesis and Evaluation of MGB Polyamide-Oligonucleotide Conjugates as Gene Expression Control Compounds.

MGB polyamide-oligonucleotide conjugates ON 1-4 with linked MGB polyamides at the 2-exocyclic amino group of a guanine base using aminoalkyl linkers were synthesized and evaluated in terms of binding affinity for complementary DNA containing the MGB polyamide binding sequence using T m and CD analyses. The MGB polyamides comprised pyrrole polyamides (Py4- and Py3-), which possess binding affinity for A-T base pairs, and imidazole (Im3-) and pyrrole-γ-imidazole (Py3-γ-Im3-) polyamide hairpin motifs, which possess binding affinity for C-G base pairs. It was found that the stability of modified dsDNA was greatly influenced by the linker length. Py4- and Py3-oligonucleotide conjugates (ON 1 (n = 4) and ON 2 (n = 4)) containing the 4-aminobutyl linker formed stable dsDNA with complementary DNA. Although Im3-oligonucleotide conjugate ON 3 (n = 4) containing the 4-aminobutyl linker formed stable dsDNA with complementary DNA, stabilization of dsDNA by the imidazole amide moiety of ON 3 (n = 4) was lower compared with the pyrrole amide moiety of ON 2 (n = 4). The Py3-γ-Im3-oligonucleotide conjugate ON 4 (n = 2), which possesses binding affinity for C-G base pairs via a pyrrole/imidazole combination and contains a 2-aminoethyl linker, showed high binding ability for complementary DNA. Furthermore, the DNA sequence recognition of MGB polyamide-oligonucleotide conjugates was investigated using single-base mismatch DNAs, which possess a mismatch base in the MGB polyamide binding sequence. The Py3-γ-Im3-oligonucleotide conjugate ON 4 (n = 2) showed high sequence recognition ability for complementary DNA.