RESUMEN
AIM: This study assessed the effects of hand-bathing on sympathetic nervous activity exacerbated by psychological stress. Participants immersed one hand in warm water for 2 min while exposed to noise, and changes in blood flow and skin temperature of the non-immersed hand were observed. METHODS: Twenty-nine healthy university students aged 20 years or older were randomly assigned to either the hand-bathing group (n = 14) or the control group (n = 15). After a brief rest in a quiet environment, participants were exposed to noise for 6 min. Those in the hand-bathing group submerged their left hand in a 40°C thermostatic bath for 2 min, starting 2 min into the noise exposure. The tympanic temperature, blood flow, and skin temperature of the non-immersed hand were continuously measured, along with blood pressure and subjective evaluations before and after the noise exposure. RESULTS: Both groups experienced a decrease in fingertip skin temperature at the start of the noise exposure, persisting longer in the control group. Conversely, the hand-bathing group showed increased fingertip skin temperature after 150 s, significantly higher after the noise exposure than the control group (p = .04). Participants in the hand-bathing group reported significantly increased overall body warmth, thermal comfort, and relaxation during hand-bathing (p = .007, p = .01, p < .001). CONCLUSIONS: The 2-min hand-bathing intervention reversed the pronounced vasoconstrictive response induced by noise exposure and elicited heightened sensations of overall body warmth, thermal comfort, and relaxation. Hand-bathing may mitigate heightened sympathetic nervous activity associated with psychological stress induced by noise exposure.
RESUMEN
A 61-year-old woman was referred to our hospital with refractory thrombocytopenia and splenomegaly. She was diagnosed with immune thrombocytopenia 3 years prior to admission and received steroid therapy. However, her platelet count started decreasing six months prior to admission. A diagnostic and therapeutic splenectomy was performed, which led to the diagnosis of histiocytic sarcoma. The patient's platelet count recovered promptly after splenectomy, and she was in complete remission for over a year.
RESUMEN
Flocculation has been recognized for hundreds of years as an important phenomenon in brewing and wastewater treatment. However, the underlying molecular mechanisms remain elusive. The lack of a distinct phenotype to differentiate between slow-growing mutants and floc-forming mutants prevents the isolation of floc-related gene by conventional mutant screening. To overcome this, we performed a two-step Escherichia coli mutant screen. The initial screen of E. coli for mutants conferring floc production during high salt treatment yielded a mutant containing point mutations in 61 genes. The following screen of the corresponding single-gene mutants identified two genes, mrcB, encoding a peptidoglycan-synthesizing enzyme and cpxA, encoding a histidine kinase of a two-component signal transduction system that contributed to salt tolerance and flocculation prevention. Both single mutants formed flocs during high salt shock, these flocs contained cytosolic proteins. ΔcpxA exhibited decreased growth with increasing floc production and addition of magnesium to ΔcpxA suppressed floc production effectively. In contrast, the growth of ΔmrcB was inconsistent under high salt conditions. In both strains, flocculation was accompanied by the release of membrane vesicles containing inner and outer membrane proteins. Of 25 histidine kinase mutants tested, ΔcpxA produced the highest amount of proteins in floc. Expression of cpxP was up-regulated by high salt in ΔcpxA, suggesting that high salinity and activation of CpxR might promote floc formation. The finding that ΔmrcB or ΔcpxA conferred floc production indicates that cell envelope stress triggered by unfavorable environmental conditions cause the initiation of flocculation in E. coli.
