Chronotypology and melatonin alterations in minimal hepatic encephalopathy

Background  

"Minimal (subclinical) hepatic encephalopathy" is a term that describes impairment of every day life activities in cirrhosis patients without clinical neurologic abnormalities. Melatonin diurnal pattern disruption and metabolic changes due to liver insufficiency can affect the human biologic clock. Our study was conducted to measure plasma melatonin levels in an attempt to correlate plasma melatonin abnormalities with liver insufficiency severity, and describe chronotypology in cirrhosis patients with minimal encephalopathy.     

Assessment of dermal wound healing and in vitro antioxidant properties of Avena sativa L.

Avena sativa L. (Poaceae) has been reported to have traditional utilization against skin diseases and inflammation. Therefore, in this study, the n-hexane, ethyl acetate, ethanol, and water extracts of A. sativa were investigated for their wound healing and antioxidant activities. Total phenol and flavonoid contents of the extracts were established spectrophotometrically. For the wound healing activity, linear incision and circular excision models on rats and mice were evaluated with a standard ointment Madecassol^®. Antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Significant wound healing activity was observed with the ointment formulation of the ethanol extract at 1% concentration. The histopathological examination results also supported the outcome of both linear incision and circular excision wound models. All of the extracts exerted low antioxidant activity in the applied assays. The present study provides a scientific evidence for the traditional usage of A. sativa in the management of wound healing.     

Solution blowing of chitosan/PLA/PEG hydrogel nanofibers for wound dressing

In this study, a kind of hydrogel nanofibers were successfully fabricated via solution blowing of chitosan (CS) and polylactic acid (PLA) solutions mixed with various contents of polyethylene glycol (PEG) to offer hydration. The nanofibers with PEG content varying were average 341-376 nm in diameter with smooth surface and distributed randomly forming three-dimension (3D) mats. Glutaraldehyde (GA) vapor was then applied to impart stability, and the cross-linking reaction mainly occurred between GA and hydroxyl groups which was confirmed by XPS. The hydrogel nanofibers showed quick absorption behavior, high equilibrate water absorption and good air permeability which could help the mats absorbing excess exudates, creating a moist wound healing environment and oxygen exchanging in wound healing. The mats also exhibited good antibacterial activities against E. coil. The combination advantages of nanofibers mats and hydrogel will help it find promising application in wound healing.     

Antibacterial Bilayered Skin Patches Made of HPMA and Quaternary Poly(4-vinyl pyridine)

This study aimed to produce poly(4-vinyl pyridine) and hydroxypropyl methacrylamide (HPMA)-based bilayer wound dressings materials enhancing healing mechanism for the wounds which have self-healing problem and high infection risk. These materials were designed to protect wound from secondary traumas caused microorganism invasion and do not have toxic substance release problem. Synthesis of quaternary poly(4-vinyl pyridine) (poly(Q4-VP)) which is the antibacterial layer of wound dressing material was carried out in two stages. At first stage, poly(4-vinyl pyridine) polymer was synthesized from 4-vinyl pyridine monomer by free radical polymerization. Then, poly(Q4-VP) was synthesized from poly(4-VP) by alkylation reaction with 6-bromocaproic acid. Resulted polymer was structurally characterized by FT-IR. The macroporous spongy structure, as the lower layer of wound dressing material, was prepared by cryogelation of HPMA. Then, the antibacterial polymer was electrospun onto the cryogel structure and bilayered material was obtained. Cryogel structure, fiber morphology and layer integration was examined by SEM. In order to enhance wound healing process, ascorbic acid (vitamin C) was loaded to cryogel layer and release was followed by spectrophotometrically. The antimicrobial properties of the materials were examined against Escherichia coli, Staphylococcus aureus and Candida albicans, respectively. According to the results, bilayered, antibacterial and antifungal against Staphylococcus aureus and Candida albicans, temporary wound dressings which can stimulate wound healing and have high swelling capacity were obtained successfully.     

Enzyme-Digested Peptides Derived from Lates calcarifer Enhance Wound Healing after Surgical Incision in a Murine Model

Surgical wounds are common injuries of skin and tissues and usually become a clinical problem. Until now, various synthetic and natural peptides have been widely explored as potential drug candidates for wound healing. Inhibition of the TNF-α signaling pathway and promotion of angiogenesis are suggested to be involved in their effects. Angiogenesis at the wound site is one of the essential requisites for rapid healing. In the present study, a novel peptide extract derived from the natural source Lates calcarifer, commonly known as sea bass or barramundi, was evaluated for its wound healing property. The specific acidic and enzymatic approaches were employed for producing sea bass extract containing small size peptides (molecular weight ranging from 1 kD to 5 kD). The cytotoxicity of the extract was examined in HaCaT and NIH3T3. After this, the effects of enzyme digested peptide extracts of sea bass on wound healing in mice were investigated. The peptide extracts (660 and 1320 mg/kg/day) and control protein (1320 mg/kg/day) was orally given to the wounded mice, respectively, for 12 days. The surgical method was improved by implanting a silicone ring at the wound site. The ring avoided the contracting effect in murine wounds, making it more closely related to a clinical condition. The results showed promising improvement at the wound site in mice. Sea bass peptide extracts accelerated the wound healing process and enhanced the microvessel formation at the wound site. The remarkable effects of this novel sea bass peptide extract in healing traumatic injuries revealed a new option for developing wound management.     

Surface modification of silk fibroin nanofibrous mat with dextran for wound dressing

In this study, we examined the effects of a dextran-modified silk fibroin nanofibrous mat (D-SFNM) on wound healing. To increase the hydrophilicity of silk fibroin (SF), the SF nanofibrous mat (SFNM) was modified with oxidized dextran. The D-SFNM absorbed water faster than the SFNM, and the swelling ratio was increased by approximately 80 % compared with the SFNM. An in vitro cell (NIH3T3) test revealed that fewer cells attached to the D-SFNM than the SFNM, but the proliferation of cells was not significantly affected by the presence of dextran. An in vivo wound healing test with mice indicated that the D-SFNM resulted in a good wound recovery effect similar to a commercial wound dressing material. The increased hydrophilicity of the D-SFNM might balance the moist environment at the wound site, which improves the wound healing compared with the SFNM.     

Insomnia in chronic renal patients on dialysis in Saudi Arabia

Background  

Studies have shown that insomnia is a common sleep disorder among patients with end-stage renal disease (ESRD). This study aimed to assess the prevalence of insomnia in Saudi patients with ESRD who are on maintenance dialysis.     

Daily rhythm of salivary and serum urea concentration in sheep

Background  

In domestic animals many biochemical and physiological processes exhibit daily rhythmicity. The aim of the present study was to investigate the rhythmic pattern of salivary and serum urea concentrations in sheep.     

Prolactin daily rhythm in suckling male rabbits

Background  

This study describes the 24-h changes in plasma prolactin levels, and dopamine (DA), serotonin (5HT), gamma-aminobutyric acid (GABA) and taurine concentration in median eminence and adenohypophysis of newborn male rabbits.     

Wound healing,decay and chemical treatment of cut potato tuber tissue

Potato tuber tissue inoculated at cutting withFusarium spp. orErwinia carotovora and exposed to conditions favorable for infection did not heal rapidly enough to prevent decay. Seven days of wound healing at 20 C and high relative humidity prior to inoculation were necessary to provide protection againstFusarium and two days were required to protect againstErwinia. Histological examination of cut and chemically treated tuber tissue revealed that the wound healing process was only minimally affected by mancozeb, zineb-streptomycin, zineb-fir bark, captan, captan-mertect, captan-fir bark, and sodium hypochlorite. Ethylmercury p-toluene-sulfonanalide and pyrrolidine induced formation of discontinuous wound periderm after 21 days of healing. Streptomycin and captan-rhodamine had very detrimental effects on wound healing and suberin formation. In general, the seed-piece treatment chemicals tested had only minor effects on normal wound healing. It is concluded that wound healing alone may not be sufficient to controlFusarium caused seed piece decay and chemical treatment is recommended to provide protection until wound healing can occur. At least two days of wound healing are required for control of decay caused byErwinia carotovora.     

Development of daily rhythmicity in heart rate and locomotor activity in the human fetus

Background  

Very little is known about the perinatal genesis of circadian rhythmicity in the human fetus. Some researchers have found evidence of rhythmicity early on in fetal development, whereas others have observed a slow development of rhythmicity during several years after birth.     

The relationship between the rate of melatonin excretion and sleep consolidation for locomotive engineers in natural sleep settings

Background  

The aim of the study was to examine the role that melatonin production plays in the regulation of sleep consolidation in a population of shiftworkers working and sleeping in their natural environments.     

A possible connection between psychosomatic symptoms and daily rhythmicity in growth hormone secretion in healthy Japanese students

Background  

Students suffering from psychosomatic symptoms, including drowsiness and feelings of melancholy, often have basic lifestyle problems. The aim of this study was to investigate whether psychosomatic complaints may be related to circadian dysfunction.     

Daily rhythm of nociception in rats

Background  

Many behavioral and physiological variables exhibit daily rhythmicity. Few investigations of the daily rhythmicity in nociception have been conducted, and conflicting results have been obtained. The present study evaluated the daily rhythmicity in nociception in Wistar rats.     

Effect of litter separation on 24-hour rhythmicity of plasma prolactin,follicle-stimulating hormone and luteinizing hormone levels in lactating rabbit does

Background  

This work describes the effect of a 48-h litter separation on 24-h patterns of plasma prolactin, FSH and LH concentration in female lactating rabbits kept under a 16:8 light-dark photoperiod (lights on at 0800 h).     

Opportunistic out-crossing in <Emphasis Type="Italic">Nicotiana attenuata</Emphasis> (Solanaceae), a predominantly self-fertilizing native tobacco

Background  

Although Nicotiana attenuata is entirely self-compatible, chemical and other floral traits suggest selection for the maintenance of advertisement for moth pollinators.     

Net ecosystem production and carbon dioxide fluxes in the Scheldt estuarine plume

Background  

A time series of 4 consecutive years of measurements of the partial pressure of CO₂ (pCO₂) in the Scheldt estuarine plume is used here to estimate net ecosystem production (NEP).     

Predictors for presence and abundance of small mammals in households of villages endemic for commensal rodent plague in Yunnan Province,China

Background  

Ninety-one rodent plague epidemics have occurred in Lianghe county, Yunnan Province, China, between 1990 and 2006. This study aimed to identify predictors for the presence and abundance of small mammals in households of villages endemic for rodent plague in Lianghe county.     

24-hour changes in circulating prolactin, follicle-stimulating hormone, luteinizing hormone and testosterone in male rats subjected to social isolation

Background  

This work analyzes the effect of social isolation (a mild stressor) on the 24-h variation of pituitary-testicular function in young Wistar rats, assessed by measuring circulating levels of prolactin, FSH, LH and testosterone.     

Fabrication of silver nanoparticle/polyvinyl alcohol/polycaprolactone hybrid nanofibers nonwovens by two-nozzle electrospinning for wound dressing

In this study, two biodegradable polymers, polycaprolactone (PCL) and polyvinyl alcohol (PVA) were used to fabricate nanofiber nonwovens (NFNs). Also, the silver nanoparticles (AgNPs) successfully reduced by using tea polyphenols (TP) and incorporated in the NFNs via electrospinning. The morphologies of the NFNs and AgNPs were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), respectively. The PCL nanofibers and PVA nanofibers interweaved each other, and AgNPs with average diameter 1.53±0.15 nm were embedded in the PVA nanofibers. The properties of electrospun NFNs were characterized by pore property, swelling/weight loss, water contact angle, mechanical property, and antibacterial activity. The nanofibers cross-linked to each other forming the 3Dnetwork porous structure with diameter about 1-1.5 μm. Although the hydrophobic PCL was added in the hybrid NFNs, the NFNs still showed hydrophilic propriety, high swelling degree (i.e. swelling degree is 330 % for 48 h), and low weight loss (i.e. weight loss is 22.4 % for 48 h). Also, the hybrid PCL/PVA/AgNPs NFNs exhibited a suitable mechanical property for wound dressings (i.e. tensile strength is 4.27 MPa, and breaking elongation is 88 %). Moreover, the hybrid NFNs effectively inhibited growth of Escherichia coli and Staphylococcus aureus. In summary, this PCL/PVA/AgNPs NFNs may provide a promising candidate for accelerating wound healing.