Objective This study was designed to determine the effect of transient receptor potential vanilloid type 4(TRPV4)on angiotensin Ⅱ(Ang Ⅱ)-induced renal injury in TRPV4-null mutant(TRPV4 -/-)mice. Methods The mice were divided into sham group and Ang Ⅱ-treated group. Ang Ⅱ was infused systemically into wild type(WT)and TRPV4 -/- mice via a miniosmotic pump for 4 weeks, and the sham mice were given with normal saline. Systolic blood pressure,urinary excretion of albumin and 8-isoprostane, serum creatinine, and the pathological changes in the kidney tissues were assayed after the 4-week treatment. Results Compared with corresponding sham mice,Ang Ⅱ infusion led to enhanced systolic blood pressure,increased urinary excretion of albumin and 8-isoprostane,increased serum creatinine(P< 0.05),and enhanced glomerulosclerosis degree and renal tubulointerstitial injury index(P< 0.05)in the WT and TRPV4 -/- mice. The result were associated with enhanced collagen levels in the kidney(P< 0.05). All of them were attenuated by the deletion of TRPV4 in the absence of alteration in blood pressure(P< 0.05). Conclusions Deletion of TRPV4 could alleviate renal injury during Ang Ⅱ-induced hypertension, suggesting that TRPV4 may contribute to the pathophysiology of angiotensin Ⅱ-induced renal injury.

Objective:To study the high risk factors of hypothermia in premature infants with gestational age ≤34 weeks, and to analyze the incidence of hypothermia before and after the implementation of the quality improvement program of hypothermia in hospital and its influence on various systemic complications, aiming to improve the early identification of hypothermia and to reveal the important clinical significance of temperature management in time.Methods:Clinical data of preterm infants born in Maternal and Child Health Hospital of Hubei Province from May 2017 to December 2018, with gestational age ≤34 weeks, and admitted within 1 hour after birth were collected.According to the admission temperature, the infants were divided into normal temperature group (36.5-37.5 ℃), mild hypothermia group (36.0-36.4 ℃), moderate hypothermia gsroup (32.0-35.9 ℃), and severe hypothermia group (<32.0 ℃). The high risk factors of hypothermia in premature infants were analyzed.The incidence and degree of hypothermia and the effects on the systemic complications before and after the implementation of the hypothermia quality improvement program were compared.Results:A total of 306 premature infants were enrolled in the study, including 63(20.6%)cases in the normal temperature group, 115(37.6%) cases in the mild hypothermia group, and 128(41.8%) cases in the moderate hypothermia group, without severe hypothermia.Infants with birth asphyxia were at higher risk for hypothermia( OR=0.195, 95% CI 0.046-0.833, P=0.027); the lower the Apgar score at 1 min( r=0.123, P=0.032)and 5 min after birth( r=0.136, P=0.017), the higher the risk of admission hypothermia.After the quality improvement project, the incidence of admission hypothermia decreased from 82.3% to 73.8%( χ2=32.67, P<0.001), and the use of pulmonary surfactant in infants with respiratory distress syndrome was significantly reduced(70.0% vs. 32.0%, χ2=40.11, P<0.001), and the incidence of hypotension within 72 hours after birth decreased(11.8% vs. 4.9%, χ2=3.87, P<0.049). Conclusion:Birth asphyxia is a risk factor for admission hypothermia in premature infants, and Apgar score is associated with admission hypothermia in premature infants.Temperature management of preterm infants can significantly reduce the incidence of hypothermia and hypotension, and reduce the use of pulmonary surfactant in respiratory distress syndrome infants.

Objective:To summarize the arrhythmic characteristics, clinical course, and prognosis of chaotic atrial tachycardia (CAT) in neonates.Methods:The researchers retrospectively analyzed and described the clinical data obtained from 30 neonates diagnosed with CAT and treated at the Maternal and Child Health Hospital of Hubei Province from January 2019 to August 2022. Prenatal and postnatal data were collected to analyze the electrocardiogram characteristics, clinical manifestations, treatment, and prognosis of CAT. Statistical analysis was performed using Mann-Whitney U and Chi-square (or Fisher's exact) tests. Results:(1) Among the 30 newborns with CAT, 19 were male infants (63%). The diagnosis age [ M(min-max)] was 11 days (1-28 days). Among them, 20 (67%) were born with full term, six (20%) had low birth weight, and 15 (50%) had abnormal cardiac structures. (2) The incidence of postnatal complex arrhythmias (coexisting with atrial fibrillation, flutter, supraventricular tachycardia, etc.) in fetuses with abnormalities, including fetal arrhythmias and fetal distress, was higher than those without abnormalities (9/14 vs 3/16, Fisher's exact, P=0.024). The median maximum atrial rate in incessant-type CAT patients (8 cases) was higher than that of paroxysmal-type CAT patients (22 cases) [400 bpm (300-700 bpm) vs 300 bpm (200-460 bpm), Z=－2.41, P=0.02]. There was no statistically significant difference in the maximum ventricular rate between the two groups [250 bpm (190-350 bpm) vs 270 bpm (180-350 bpm), Z=－0.26, P=0.800]. There were 19 cases (63%) complicated with diseases that seriously affected the respiratory or circulatory system, or infectious diseases. (3) Antiarrhythmic drugs were used in 23 cases (77%), including six cases treated with one drug, 12 cases with two drugs, and five cases with more than two drugs, mainly propafenone (20 cases, 67%). Seven cases (23%) with no complex arrhythmia turned to normal rhythm spontaneously without using antiarrhythmic drugs. Among all cases, 16 (53%) achieved clinical cures after complete cardioversion during hospitalization, while 14 cases (47%) were not cured. (4) The children who were cured during hospitalization were followed up for 1.5 months (2 weeks to 8 months) after discharge, and no recurrence was observed, indicating good growth and development. Untreated patients were followed up for 1.9 years (3.5 months to 4.4 years), of which seven cases completely recovered within six months, and the other seven cases continued to recur. However, no adverse outcomes, such as death, occurred. Conclusions:The overall prognosis of neonatal CAT is favorable. A history of fetal arrhythmia and intrauterine distress may increase the risk of CAT. Active drug treatment should be considered for children of CAT with complex arrhythmia.