Unlocking the potential of phenolated kraft lignin as a versatile feed additive.

Lignin, a renewable natural antioxidant and bacteriostat, holds promise as a versatile, cost-effective feed additive. However, traditional industrial lignin faces limitations, including low reactivity, poor uniformity, and unstable properties, necessitating chemical modification. Complex modification methods pose economic and toxicity challenges, so this study adopted a relatively simple alkali-catalyzed phenolization approach, using phenol, catechol, and pyrogallol to modify kraft lignin, and characterized the resulting products using various techniques. Subsequently, their antioxidant, antibacterial, adsorption properties for heavy metal ions and mycotoxins, growth-promoting properties, and antiviral abilities were assessed. The phenolation process led to lignin depolymerization and a notable increase in phenolic hydroxyl content, particularly in pyrogallol-phenolated lignin (Py-L), rising from 3.08 to 4.68 mmol/g. These modified lignins exhibited enhanced antioxidant activity, with over 99 % inhibition against E. coli and S. aureus, and remarkable adsorption capacities for heavy metal ions and mycotoxins. Importantly, Py-L improved the growth performance of mice and reduced influenza mortality. Furthermore, density functional theory calculations elucidated the mechanism behind the enhanced antioxidant properties. This study presents a promising avenue for developing versatile feed additives to address challenges related to animal feed antioxidant supplementation, bacterial control, and growth promotion.

[Influence of different sleep stages on respiratory regulation in normal humans].

OBJECTIVE: To understand the influence of different sleep stages on respiratory regulation in normal people. METHODS: We measured ventilation (VE) and occlusion pressure (P0.1) responses to hyperoxia hypercapnia (deltaVE/deltaPaCO2, deltaP0.1/deltaPaCO2) and isocapnic hypoxia (deltaVE/deltaSaO2 and deltaP0.1/deltaSaO2) in eleven non-snoring healthy people during wakefulness and during non-rapid eye movement (NREM) I + II, NREM III+IV, and rapid eye movement (REM) sleep stages. RESULTS: During NREM I + II and NREM III+IV, the normal subjects showed no significant decrease in P0.1, deltaP0.1/deltaSaO2 and deltaP0.1/deltaPaCO2 (P > 0.05), but deltaVE/ deltaSaO2 and deltaVE/ deltaPaCO2 decreased significantly (P < 0.05). During REM sleep, P0.1 maintained the level during wakefulness, but both hypoxic and hypercapnic responses decreased significantly (P < 0.05). CONCLUSIONS: Sleep has significant influence on respiratory regulation in normal people. The respiratory drive (P0.1) in both NREM and REM sleep stages could maintain the awake level due to an effective compensation to the increase of upper airway resistance. The P0.1 responses to both hypoxia and hypercapnia decrease only in REM sleep stage, which is in consistent with the clinical phenomenon that sleep disordered breathing occurs in REM in normal people.

[Respiratory control during sleep and the development of nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: It is assumed that the reduced ventilatory control during sleep may be related to the nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and daytime CO(2) retention. METHODS: Oxygen desaturation index (ODI(4)), sleep time spent when SaO(2) was below 90% (SIT(90)), the lowest SaO(2) (LSaO(2)) and the mean SaO(2) (MSaO(2)) during sleep were measured in 24 OSAHS patients with daytime PaCO(2) > or = 45 mm Hg and 39 with PaCO(2) < 45 mm Hg. Hypoxic (DeltaP(0.1)/DeltaSaO(2)) and hypercapnic (DeltaP(0.1)/DeltaPaCO(2)) responsiveness were measured in 11 eucapnic and 4 hypercapnic patients during wakefulness, NREM and REM sleep stages. RESULTS: Compared with the eucapnic patients, all the hypercapnic patients had more severe hypoxia during sleep (P < 0.05). Although both groups had similar chemical responsiveness during wakefulness, the hypercapnic patients had lower DeltaP(0.1)/DeltaSaO(2) and DeltaP(0.1)/DeltaPaCO(2) during both REM and NREM sleep (P < 0.05). CONCLUSION: The depressed chemical responsiveness during sleep plays an important role in the development of nocturnal hypoxia in OSAHS patients with daytime CO(2) retention.

[HLA-DRB and -DQB allele contribution to narcolepsy susceptibility in Chinese patients with narcolepsy].

OBJECTIVES: To study the association of narcolepsy with HLA class II alleles in Chinese narcoleptic patients. METHODS: 31 patients with narcolepsy underwent brain computed tomography (CT) scan and magnetic resonance imaging (MRI) testing. All patients received a MSLT test following a routine night's sleep, and serological HLA typing for HLA DR(2). 21 patients received PCR-SSP HLA DR and DQ typing. RESULTS: All patients had sleepiness and cataplexy. There was no evidence for other functional or structural diseases. Sleep paralysis was elicited in 45%; hypnagogic hallucinations, in 61%. Mean sleep latency on MSLT was 2.1 min +/- 1.3 min; sleep-onset rapid eye movement (SOREM) occurred during 2/5 naps in 30 of 31 patients. The average number and latency of SOREM episodes were 4.2 +/- 1.0 episodes and 4.0 min +/- 1.8 min, respectively. All patients but one were HLA DR(2) positive and 86% were HLADRB(1) * 1501-HLADQB(1)*0602 positive. CONCLUSIONS: HLA DR(2) and HLADQw6 are markers for narcolepsy-cataplexy in Chinese.