RESUMEN
PURPOSE: Perioperative shivering is common and can occur as a result of hypothermia or changes in the threshold of thermoregulation. Droperidol usage for anesthesia is currently limited to its sedative and antiemetic effects. We investigated the effects of high and low doses of droperidol on the shivering threshold in rabbits. METHODS: Forty-two male Japanese white rabbits were anesthetized with isoflurane and randomly assigned to the control, high-dose, or low-dose group. Rabbits in the high-dose group received a 5 mg/kg droperidol bolus followed by continuous infusion at 5 mg/kg/h, those in the low-dose group received a 0.5 mg/kg droperidol bolus, and those in the control group received the same volume of saline as the high-dose group. Body temperature was reduced at a rate of 2-3 °C/h, and the shivering threshold was defined as the subject's core temperature (°C) at the onset of shivering. RESULTS: The shivering thresholds in the control, high-dose, and low-dose groups were 38.1 °C ± 1.1 °C, 36.7 °C ± 1.2 °C, and 36.9 °C ± 1.0 °C, respectively. The shivering thresholds were significantly lower in the high-dose and low-dose groups than in the control group (P < 0.01). The thresholds were comparable between the high-dose and low-dose groups. CONCLUSIONS: Droperidol in high and low doses effectively reduced the shivering threshold in rabbits. Droperidol has been used in low doses as an antiemetic. Low doses of droperidol can reduce the incidence of shivering perioperatively and during the induction of therapeutic hypothermia.
Asunto(s)
Hipotermia , Isoflurano , Animales , Conejos , Masculino , Tiritona/fisiología , Droperidol/farmacología , Temperatura Corporal/fisiología , Isoflurano/farmacología , Hipotermia/tratamiento farmacológicoRESUMEN
BACKGROUND: We previously reported that each 100 mg dL- 1 reduction in blood glucose over the range from ≈90 to > 300 mg dL- 1 decreases the shivering threshold (triggering core temperature) in rabbits by 1 °C. However, the effects of lower blood glucose concentrations has yet to be evaluated. We thus evaluated the relationship between the shivering threshold and blood glucose concentration over the mild-to-severe hypoglycemic range. METHODS: Thirty-nine rabbits were lightly anaesthetized with isoflurane and randomly assigned to one of the three groups: 1) severe hypoglycemia, insulin and dextrose infusions titrated to achieve blood glucose concentration at 45-75 mg dL- 1; 2) mild hypoglycemia, insulin and dextrose infusions titrated to achieve blood glucose concentration at 75-100 mg dL- 1; and 3) saline infusion. Cooling by colonic perfusion of water at 10 °C was continued until shivering occurred or esophageal core temperatures reached to 34 °C. RESULTS: The shivering threshold in the severe hypoglycemic rabbits was 35.7 ± 1.1 °C (mean ± SD); the thresholds in the mild hypoglycemic rabbits was 37.0 ± 0.7 °C; and the threshold in the control rabbits was 37.9 ± 1.0 °C. The shivering threshold increased linearly with blood glucose concentration: shivering threshold (°C) = 0.032 â [blood glucose concentration (mg dL- 1)] + 34.1, R2 = 0.45. The shivering threshold thus decreased by approximately 1 °C for each 31 mg dL- 1 decrease in blood glucose concentration. CONCLUSIONS: There was a linear relationship between blood glucose and the shivering threshold over the range from severe hypoglycemia to normoglycemia. Blood glucose perturbations in the hypoglycemic range reduced the shivering threshold about three times as much as previously reported for the hyperglycemic range.
Asunto(s)
Hipoglucemia , Umbral Sensorial , Tiritona , Anestésicos por Inhalación/administración & dosificación , Animales , Glucemia/análisis , Hipoglucemia/inducido químicamente , Isoflurano/administración & dosificación , Modelos Animales , Conejos , Distribución Aleatoria , Índice de Severidad de la EnfermedadRESUMEN
We synthesized cyclic chiral compounds [(R)/(S)-D2s] by linking a photoresponsive bisbenzothienylethene (BTE) moiety with an axially chiral binaphthyl moiety. Chiral nematic liquid crystals (N*-LCs) were prepared by adding chiral compounds as dopants to host N-LCs. These N*-LCs exhibited reversible chirality inversion upon photoisomerization between the open and closed forms of the BTE moiety. Here, the mechanism underlying chirality inversion in photoresponsive N*-LCs was investigated by comparing the helical twisting powers (HTPs) of (R)-D2s with those of analogous compounds. It was found that the helical inversion of N*-LCs containing (R)-D2s is governed by a delicate balance between two types of opposite helicity, i.e., the right-handed helicity of the inherently chiral binaphthyl moiety and the left-handed helicity of the BTE moiety bearing intramolecularly induced chirality. Namely, (R)-D2s induced chirality of the BTE moiety, which is attributed to intramolecular chirality transfer from the axially chiral binaphthyl moiety to the BTE moiety. Thus, (R)-D2s are chiral compounds with double chirality consisting of an intrinsically chiral moiety and an intramolecularly induced chiral moiety. Photocontrol of the helical senses and reversible photoinversion of the N*-LCs are achieved by utilizing UV and visible light irradiation and the steric effects of the substituents at the binaphthyl rings in (R)-D2s. In addition, photocontrol of the induced circularly polarized luminescence (CPL) was achieved using the photoinvertible N*-LC. The achiral aromatic conjugated copolymers that exhibited red, green, and blue fluorescence were dissolved and mixed in the present N*-LC, and they exhibited left- and right-handed white CPL with large dissymmetry factors (|glum|) ranging from 0.2 to 1.0. The CPLs were reversibly photoswitched due to photoisomerization between the open and PSS forms of the chiral compounds through UV and visible light irradiation.
RESUMEN
This case illustrates the complex interactions of the immune responses after vaccination and highlights their potential connections to various autoimmune conditions. A 22-year-old man with quiescent ulcerative colitis (UC) presented with abdominal pain, rectal bleeding, and thrombocytopenia 7 days after receiving the third coronavirus disease 2019 mRNA vaccination. Laboratory data confirmed the diagnosis of immune thrombocytopenia. High-dose intravenous immunoglobulin administration boosted the patient's platelet count. Simultaneously, colonoscopy revealed that his UC had relapsed. Although salazosulfapyridine briefly improved his symptoms, his stool frequency worsened one week later. The patient also developed pyoderma gangrenosum. Subsequent treatment with infliximab notably improved both pyoderma gangrenosum and UC.
Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Colitis Ulcerosa , Púrpura Trombocitopénica Idiopática , Piodermia Gangrenosa , Trombocitopenia , Adulto , Humanos , Masculino , Adulto Joven , Enfermedad Crónica , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/diagnóstico , COVID-19/complicaciones , Vacunas contra la COVID-19/efectos adversos , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/etiología , Piodermia Gangrenosa/tratamiento farmacológico , Piodermia Gangrenosa/etiología , Piodermia Gangrenosa/diagnóstico , RecurrenciaRESUMEN
BACKGROUND: Walled-off necrosis (WON) is a late complication of acute pancreatitis possibly with a fatal outcome. Even for WON spreading to the retroperitoneal space, percutaneous endoscopic necrosectomy (PEN) can be an alternate approach to surgical necrosectomy, particularly for the older individuals or patients with poor condition because of WON. CASE SUMMARY: An 88-year-old man was admitted to our hospital with a jaundice. Endoscopic retrograde cholangiopancreatography (ERCP) was performed to improve jaundice; however, post-ERCP pancreatitis developed. The inflammation of pancreatitis spread widely from the right retroperitoneal cavity to the pelvis, and WON was formed 4 wk later. A percutaneous drainage tube was placed into the WON under computed tomography guidance. However, the drainage did not ameliorate clinical symptoms including fever, which assured less invasive necrosectomy. A metallic stent for the upper gastrointestinal (GI) tract was placed from the percutaneous drainage route. An upper GI endoscope was inserted into the inside of the WON through the metallic stent, and the necrotic tissues were bluntly removed with a snare forceps. Ten times of these necrosectomies resulted in the near-complete removal of necrotic tissues. These procedures consequently abated his fever and remarkable improvement in blood tests. CONCLUSION: PEN for WON occurring in the retroperitoneal space was safe and effective for very old individuals.
RESUMEN
Shivering after surgery or during therapeutic hypothermia can lead to serious complications, such as myocardial infarction and respiratory failure. Although several anesthetics and opioids are shown to have anti-shivering effects, their sedative and respiratory side effects dampen the usefulness of these drugs for the prevention of shivering. In the present study, we explored the potential of a novel ultrashort-acting benzodiazepine, remimazolam, in the prevention of shivering using a rabbit model of hypothermia. Adult male Japanese white rabbits were anesthetized with isoflurane. The rabbits received saline (control), remimazolam (either 0.1 or 1 mg/kg/h), or remimazolam + flumazenil, a selective γ-aminobutyric acid (GABA) type A receptor antagonist (n = 6 each). Thirty minutes after discontinuation of the drugs, cooling was initiated by perfusing 10°C water via a plastic tube positioned in the colon until the animal shivered. Core body temperature and hemodynamic and physiological parameters were recorded. Remimazolam at 1 mg/kg/h significantly lowered the core temperature change during shivering (-2.50 ± 0.20°C vs. control: -1.00 ± 0.12°C, p = 0.0009). The effect of 1 mg/kg/h remimazolam on the core temperature change was abolished by flumazenil administration (-0.94 ± 0.16°C vs. control: -1.00 ± 0.12°C, p = 0.996). Most of the hemodynamic and physiological parameters did not differ significantly among groups during cooling. Remimazolam at a clinically relevant dose successfully suppressed shivering in rabbits via the GABA pathway even after its anesthetic effects likely disappeared. Remimazolam may have the potential to prevent shivering in patients undergoing surgery or therapeutic hypothermia.
RESUMEN
Morphological descriptions of phyllosoma larvae are essential for correct species identification and investigating the spatiotemporal distribution and recruitment process of spiny and slipper lobsters. Species identification of the phyllosoma larvae in the Scyllarinae subfamily is particularly difficult because of the morphological similarities among species and the scarcity of morphological information describing correct species identity. We extracted mid-to final-stage (V to VIII) phyllosoma larvae (n = 12) belonging to the subfamily Scyllarinae from several plankton samples collected in the Pacific and then performed molecular species identification using mitochondrial DNA COI and 16S rDNA sequence analyses. Three larvae collected around the Ryukyu Archipelago were identified as Chelarctus aureus (stage VI to VIII), and four collected around the Ryukyu Archipelago and Ogasawara Islands were identified as C. virgosus (V to VIII). One larva (V) collected in the central South Pacific was determined to be a subspecies of C. crosnieri. DNA barcodes could not be made for the remaining four larvae (V to VIII) collected around the Ryukyu Archipelago (designated by ?Chelarctus sp-1). Based on the morphological characteristics of the C. virgosus phyllosoma described in this study and the adult distributions reported to date, C. cultrifer phyllosomas previously reported in Japanese and Taiwanese waters are likely to be C. virgosus. This paper also presents a set of diagnostic morphological characteristics that can be used to discriminate among these four species of Chelarctus and from other genera in the subfamily Scyllarinae.
RESUMEN
Flavonoids are a subclass of polyphenols which are attractive, due to possessing various physiological activities, including a radioprotective effect. Tumor suppressor p53 is a primary regulator in the radiation response and is involved in the pathogenesis of radiation injuries. In this study, we revealed that isorhamnetin inhibited radiation cell death, and investigated its action mechanism focusing on DNA damage response. Although isorhamnetin moderated p53 activity, it promoted phosphorylation of ataxia telangiectasia mutated (ATM) and enhanced 53BP1 recruitment in irradiated cells. The radioprotective effect of isorhamnetin was not observed in the presence of ATM inhibitor, indicating that its protective effect was dependent on ATM. Furthermore, isorhamnetin-treated mice survived gastrointestinal death caused by a lethal dose of abdominal irradiation. These findings suggested that isorhamnetin enhances the ATM-dependent DNA repair process, which is presumably associated with the suppressive effect against GI syndrome.