Diversified Mammalian Visuasl Adaptations to Bright- or Dim-Light Environments.

Photic niche shifts of mammals are associated with changing visual capabilities, primarily mediated by three visual pigments, two (SWS1 and M/LWS) of them for color vision and rhodopsin (RH1) for dim-light vision. To further elucidate molecular mechanisms of mammalian visual adaptations to different light environments, a systematic study incorporating evolutionary analyses across diverse groups and in vitro assays have been carried out. Here, we collected gene sequences for the three opsins from 220 species covering all major mammalian clades. After screening for cone opsin gene losses, we estimated selective pressures on each of the three genes and compared the levels of selection experienced by species living in bright- and dim-light environments. SWS1 pigment is shown to experience accelerated evolution in species living in bright-light environments as has RH1 in aquatic cetaceans, indicating potential shifts for ecological adaptations. To further elucidate the functional mechanisms for these two pigments, we then carried out site-directed mutagenesis in representative taxa. For SWS1, violet and ultraviolet sensitivities in the pika and mouse are mainly affected by substitutions at the critical sites 86 and 93, which have strong epistatic interaction. For RH1, the phenotypic difference between the sperm whale and bovine sequences is largely contributed by a substitution at site 195, which could be critical for dim-light sensation for deep-diving species. Different evolutionary patterns for the visual pigments have been identified in mammals, which correspond to photic niches, although additional phenotypic assays are still required to fully explain the functional mechanisms.

The Security and Driving Factors of the Innovative Ecosystem: Evidence from the Yellow River Basin.

Ecological protection and high-quality development of the Yellow River Basin have always been seriously restricted by its unreasonable economic structure and low level of innovation. A two-dimensional indicator system was constructed to evaluate the security of the innovative ecosystem in the Yellow River Basin and identify its driving factors. The R clustering, the method of coefficient of variation, and the entropy method were used to screen and empower the indicators, and then the Lotka-Volterra symbiotic coupling model was introduced innovatively to calculate the security index and analyze its spatio-temporal evolution. Finally, the fixed-effect regression model and Granger causality test were used to identify the driving factors. It was found that (1) The security of the innovative ecosystem in the Yellow River Basin from 2012 to 2021 showed an overall upward tendency, but it was still at a low level, and the innovative landscape community lagged behind the innovative biome for a long time; (2) The security status of the innovative ecosystem showed a differential pattern of "high in the east and south, and lower in the west and north"; (3) Innovation transformation ability, innovation consumption capacity, education, and natural ecological environment are crucial driving factors for improving the security level of an innovative ecosystem.

Convergent Phenotypic Evolution of Rhodopsin for Dim-Light Sensing across Deep-Diving Vertebrates.

Rhodopsin comprises an opsin attached to a retinal chromophore and is the only visual pigment conferring dim-light vision in vertebrates. On activation by photons, the retinal group becomes detached from the opsin, which is then inactive until it is recharged. Of all vertebrate species, those that dive face unique visual challenges, experiencing rapid decreases in light level and hunting in near darkness. Here, we combine sequence analyses with functional assays to show that the rhodopsin pigments of four divergent lineages of deep-diving vertebrates have undergone convergent increases in their retinal release rate. We compare gene sequences and detect parallel amino acids between penguins and diving mammals and perform mutagenesis to show that a single critical residue fully explains the observed increases in retinal release rate in both the emperor penguin and beaked whale. At the same time, we find that other shared sites have no significant effect on retinal release, implying that convergence does not always signify adaptive significance. We propose that accelerated retinal release confers rapid rhodopsin recharging, enabling the visual systems of diving species to adjust quickly to changing light levels as they descend through the water column. This contrasts with nocturnal species, where adaptation to darkness has been attributed to slower retinal release rates.

Negative Life Events and Antenatal Depression among Pregnant Women in Rural China: The Role of Negative Automatic Thoughts.

BACKGROUND: Few studies have looked at the relationship between psychological and the mental health status of pregnant women in rural China. The current study aims to explore the potential mediating effect of negative automatic thoughts between negative life events and antenatal depression. METHODS: Data were collected in June 2012 and October 2012. 495 rural pregnant women were interviewed. Depressive symptoms were measured by the Edinburgh postnatal depression scale, stresses of pregnancy were measured by the pregnancy pressure scale, negative automatic thoughts were measured by the automatic thoughts questionnaire, and negative life events were measured by the life events scale for pregnant women. We used logistic regression and path analysis to test the mediating effect. RESULTS: The prevalence of antenatal depression was 13.7%. In the logistic regression, the only socio-demographic and health behavior factor significantly related to antenatal depression was sleep quality. Negative life events were not associated with depression in the fully adjusted model. Path analysis showed that the eventual direct and general effects of negative automatic thoughts were 0.39 and 0.51, which were larger than the effects of negative life events. CONCLUSIONS: This study suggested that there was a potentially significant mediating effect of negative automatic thoughts. Pregnant women who had lower scores of negative automatic thoughts were more likely to suffer less from negative life events which might lead to antenatal depression.

Biomarkers for assessing mucosal barrier dysfunction induced by chemotherapy: Identifying a rapid and simple biomarker.

BACKGROUND: Chemotherapy-induced mucosal barrier dysfunction is of clinical interest. However, the assessment of mucosal barrier dysfunction still poses challenges. In this study, we compared several biomarkers with the dual sugar gut permeability test for assessing mucosal barrier dysfunction during chemotherapy. METHODS: Forty-two patients with gastric or colorectal cancer underwent chemotherapy, including FAM or FOLFOX4 regimens. Patients were asked to grade and record their symptoms of gastrointestinal toxicity daily. The urinary lactulose-mannitol ratio was measured to assess the intestinal permeability. Plasma levels of citrulline, diamine oxidase (DAO), D-lactic acid, and endotoxin were also measured. Intestinal permeability was observed in the subgroup of patients with diarrhea or constipation. RESULTS: The urinary lactulose-mannitol ratio and plasma citrulline levels increased on the third and sixth post-chemotherapy days, respectively. There were no significant differences in the plasma levels of D-lactic acid, endotoxin or DAO activity compared to their levels before chemotherapy. The urinary lactulose-mannitol ratio in diarrhea patients was significantly higher than in constipation patients. CONCLUSIONS: These results indicate that the urinary lactulose-mannitol ratio and plasma citrulline level are appropriate biomarkers for assessing mucosal barrier dysfunction in patients receiving chemotherapy. Mucosal barrier dysfunction in diarrhea patients was greater than in constipation patients.

Depression and its risk factors among pregnant women in 2008 Sichuan earthquake area and non-earthquake struck area in China.

BACKGROUND: On May 12, 2008, a powerful 8.0 magnitude earthquake struck China's Sichuan province. While some studies have assessed the mental and physical wellbeing of disaster victims, few have examined the long-term impact of natural disasters on pregnant women's mental health. As such, this study aims to assess whether the Sichuan earthquake continues to negatively affect women's mental health, 4 years since its occurrence. In addition, predictive and protective risk factors of depressive symptoms among pregnant women were also identified. METHODS: From June 2012 to October 2012, 520 pregnant women were interviewed, of whom 253 were from an earthquake struck area and 267 were from a non-earthquake struck area. Symptoms of antenatal depression were measured using the Edinburgh Postnatal Depression Scale (EPDS) with a cutoff of≥10. RESULTS: The prevalence rate of depression among pregnant women in the earthquake area was 34.5% (95% CI, 28.9-40.6), while the rate in the non-earthquake area was 39.6% (95% CI, 33.9-45.5). The perceived stresses associated with pregnancy and social support from husbands are significantly correlated with antenatal depression. LIMITATIONS: Lack of diagnosis for antenatal depression and it is a self-report evaluation. CONCLUSIONS: This study found that the Sichuan earthquake does not necessarily have a long-lasting effect on pregnant women who were once victims of the disaster. It was found that pregnant women who experience high levels of pressures from the pregnancy and receive medium support from husbands are more susceptible to experience antenatal depression than pregnant women who perceive higher levels of support from husbands.

Combination of fibrin glue with growth hormone augments healing of incomplete intestinal anastomoses in a rat model of intra-abdominal sepsis: a dynamic study.

This study was devised to investigate whether fibrin glue (FG) in combination with growth hormone (GH) could have a beneficial effect at a late period (14 days) after injury. Male Wistar rats, with abdominal sepsis induced by an incomplete anastomosis, were divided into three groups. In the control group, the rats got incomplete anastomoses sutured alone; in the FG and FG/GH groups, anastomoses protection was performed with application of FG alone or in combination with GH. The anastomotic bursting pressure (ABP) was significantly higher in the FG/GH group than that of the FG group on postoperative day (POD) 5 (p < .01), while it could not be measured from POD 7 to POD 14 because of intestinal dehiscence. There was no difference between FG and FG/GH group on POD 3 and POD 5 in anastomotic tensile strength, which was significantly higher in the FG/GH group than that of the FG group from POD 7 to POD 14 (p < .001). Hydroxyproline content of the FG/GH group was significantly higher than that of the control from POD 3 and that of the FG group from POD 5 (p < .05). Combination of FG with GH had a synergistic effect to improve intestinal anastomotic healing over a limited 14-day course of observation.

[Serum citrulline: a potential marker for intestinal epithelial mass and absorption capacity in short bowel syndrome patients].

OBJECTIVE: To investigate the potential role of serum citrulline level in evaluating the intestinal absorptive area and capacity in patients with short bowel syndrome (SBS). METHODS: Serum citrulline concentration was determined using high performance liquid chromatography (HPLC) in SBS patients (n=22) and healthy controls (n=33). In SBS patients, the remnant small bowel lengths and diameters were measured by radiography, and their 5- hour urine D- xylose excretion and intestinal protein absorption were also determined. The correlationship of serum citrulline level with remnant small bowel length, surface area, protein and D- xylose absorption was analyzed. The 6 patients receiving intestinal rehabilitative therapy, serum citrulline level, protein and D- xylose absorption after therapy were also measured. RESULTS: Serum citrulline level of SBS patients was significantly lower than that of healthy controls [(5.94+/- 2.65) vs [(16.87 +/- 5.97) micromol/L, P < 0.01]. In SBS patients, serum citrulline was positively correlated with remnant small bowel length and surface area (r=0.82 and r=0.86 respectively). There was also a significant correlationship of serum citrulline level with 5- hour D- xylose excretion (r=0.56) and intestinal protein absorption (r=0.48). Serum citrulline, 5- hour D- xylose excretion and intestinal protein absorption were all significantly raised in patients after rehabilitative therapy, although no correlation of increasing percentage was found among above three parameters. CONCLUSIONS: Serum citrulline concentration is positively correlated with intestinal absorptive area and capacity in SBS patients. It is a potential marker for evaluating the severity of intestinal failure and the efficacy of rehabilitative therapy in short bowel patients.

Oral glutamine ameliorates chemotherapy-induced changes of intestinal permeability and does not interfere with the antitumor effect of chemotherapy in patients with breast cancer: a prospective randomized trial.

AIMS AND BACKGROUND: Sixty patients with breast cancer were randomly assigned to oral glutamine or placebo pre-neoadjuvant chemotherapy (CEF regimen). METHODS AND STUDY DESIGN: Oral glutamine supplementation was continued for at least 12 days. Patients kept a daily record of diarrhea and stomatitis. The plasma glutamine level, intestinal permeability (lactulose-mannitol test), and tumor size were analyzed. The expression of Ki-67 and PCNA antigens in breast carcinoma was assessed. RESULTS: The plasma glutamine level was significantly higher in the glutamine group than in the placebo group (420.39 +/- 52.39 mmol/L vs 309.76 +/- 42.34 mmol/L, P < 0.05). After one cycle of chemotherapy, the lactulose-mannitol ratio was higher in the placebo group than in the glutamine group (0.0630 +/- 0.0091 vs 0.0471 +/- 0.0094, P < 0.05). No differences were observed in the grades of stomatitis and diarrhea, in the changes in tumor size, and in the expression of Ki-67 and PCNA antigens between the two groups. CONCLUSIONS: Prophylactic oral glutamine could ameliorate the neoadjuvant chemotherapy-induced increase in intestinal permeability, but had no significant positive clinical effect on stomatitis and diarrhea and did not interfere with the antitumor effect of chemotherapy.

The effect of glutamine-supplemented total parenteral nutrition on nutrition and intestinal absorptive function in a rat model.

The aim of the present study was to evaluate the effect of short-term (7 days) glycyl-glutamine-supplemented total parenteral nutrition (TPN) on nutrition and intestinal absorptive function in a rat model. Thirty Wistar rats, weighting 140-180 g, were divided into three groups (n=10) randomly. The animals received isonitrogenous and isocaloric TPN solutions for 7 days. The nitrogen was supplied by glycyl-glutamine dipeptide-supplemented amino acid solution (group G), and two standard amino acid solutions (group V, group N), respectively. Body weight, plasma glutamine level, nitrogen balance, total tissue water and intestinal absorptive function, assessed by (15-N)-glycine absorption, were investigated. Body weight decreased in three groups at the end of TPN; there was no significant difference in relative body-weight changes. There was a significant improvement of cumulative nitrogen balance and nitrogen retention in group G compared to other groups (P<0.05). There was no significant difference in intestinal glycine absorption (P>0.05) among the three groups. Total tissue water of left thigh muscle was significantly higher in group V and group N than that in group G (P<0.05). The results indicated that short-term (7 days) TPN supplemented with glycyl-glutamine improved plasma glutamine level and nitrogen balance, decreased water content of muscle, but had no beneficial effect on absorptive function in a rat model.

Intestinal barrier damage caused by trauma and lipopolysaccharide.

AIM: To investigate the intestinal barrier function damage induced by trauma and infection in rats. METHODS: Experimental models of surgical trauma and infection were established in rats. Adult Sprague-Dawley rats were divided into 4 groups: control group (n = 8), EN group (n = 10), PN group (n = 9) and Sep group (n = 8). The rats in PN and Sep groups were made into PN models that received isonitrogenous, isocaloric and isovolumic TPN solution during the 7-d period. Rats in EN and Sep groups received laparotomy and cervical catheterization on day 1 and received lipopolysaccharide injection intraperitoneally on d 7. On the 7(th) day all the animals were gavaged with lactulose and mannitol to test the intestinal permeability. Twenty-four hours later samples were collected and examined. RESULTS: The inflammatory responses became gradually aggravated from EN group to Sep group. The mucosal structure of small intestine was markedly impaired in PN and Sep groups. There was a low response in IgA level in Sep group when compared with that of EN group. Lipopolysaccharide injection also increased the nitric oxide levels in the plasma of the rats. The intestinal permeability and bacterial translocation increased significantly in Sep group compared with that of control group. CONCLUSION: One wk of parenteral nutrition causes an atrophy of the intestinal mucosa and results in a moderate inflammatory reaction in the rats. Endotoxemia aggravates the inflammatory responses that caused by laparotomy plus TPN, increases the production of nitric oxide in the body, and damages the intestinal barrier function.

Functional hepatic flow in patients with liver cirrhosis.

AIM: To evaluate hepatic reserve function by investigating the change of functional hepatic flow and total hepatic flow in cirrhotic patients with portal hypertension. METHODS: HPLC method was employed for the determination of concentration of D-sorbitol in human plasma and urine. The functional hepatic flow (FHF) and total hepatic flow (THF) were determined by means of modified hepatic clearance of D-sorbitol combined with duplex doppler color sonography in 20 patients with cirrhosis and 10 healthy volunteers. RESULTS: FHF, evaluated by means of the D-sorbitol clearance, was significantly reduced in patients with cirrhosis in comparison to controls (764.74+/-167.91 vs 1195.04+/-242.97 mL/min, P<0.01). While THF was significantly increased in patients with cirrhosis in comparison to controls (1605.23+/-279.99 vs 1256.12+/-198.34 mL/min, P<0.01). Portal blood flow and hepatic artery flow all were increased in cirrhosis compared to controls (P<0.05 and P<0.01). D-sorbitol total clearance was significantly reduced in cirrhosis compared to control (P<0.01), while D-sorbitol renal clearance was significantly increased in cirrhosis (P<0.05). In controls FHF was similar to THF (1195.05+/-242.97 vs 1256.12+/-198.34 mL/min, P=0.636), while FHF was significantly reduced compared with THF in cirrhosis (764.74+/-167.91 vs 1605.23+/-279.99 mL/min, P<0.01). CONCLUSION: Our method that combined modified hepatic clearance of D-sorbitol with duplex doppler color sonography is effective in the measurement of FHF and THF. FHF can be used to estimate hepatic reserve function.

Prophylactic treatment with growth hormone improves intestinal barrier function and alleviates bacterial translocation in stressed rats.

BACKGROUND: Damage to the gut barrier often occurs during critical illnesses. In such cases, it is very important to alleviate impairment of the intestinal barrier and protect intestinal barrier function. This study investigated the protective effect of growth hormone on intestinal barrier function in rats under stress. METHODS: This study consisted of prospective, randomized, and controlled animal experiments. Twenty-five Sprague-Dawley rats served as total parenteral nutrition (TPN) models and were divided into three groups: TPN group, sepsis (Sep) group, and growth hormone (GH) group. Another 8 rats served as normal controls. Each group received different stress stimuli. Rats were fed for 7 days, and samples were taken for examination 24 hours after gavaging with dual saccharides. RESULTS: The architecture of the small intestinal mucosa in the Sep group showed the most severe damage among all groups. Nitric oxide levels in blood plasma and immunoglobulin A levels in the intestinal mucosa of the GH group were significantly lower than in the Sep group (P < 0.02). There were no significant changes in CD3 counts and in the CD4/CD8 ratio between the four groups. Dual sugar tests and bacteriological examinations revealed that intestinal permeability and rate of bacterial translocation in the GH group were lower than in the Sep group (P < 0.01, respectively). CONCLUSION: Prophylactic treatment with growth hormone can alleviate damage to intestinal barrier function caused by trauma and endotoxemia in rats under stress.

[Determination of gamma-aminobutyric acid and glutamate in human gastric mucosa by high performance liquid chromatography].

A method for analysis of gamma-aminobutyric acid (GABA) and glutamate (Glu) in human gastric mucosa by high performance liquid chromatography (HPLC) was developed. A gradient elution was used for the separation and quantification of GABA and Glu after pre-column derivatization with phenylisothiocyanate (PITC). The column was Pico x Tag for free amino acids. GABA and Glu were determined with UV detector at 254 nm. Good linearities were observed within the ranges from 0.125 to 6.25 micromol/L for GABA and from 0.025 to 2.5 mmol/L for Glu. The average recoveries were 95.4% for GABA and 93.5% for Glu. The intra- and inter-precision values were within 3.56% and 7.47% for GABA, and 1.12% and 5.98% for Glu, respectively. The method is sensitive, specific and accurate. It can be used in the determination of GABA and Glu in human gastric mucosa tissue. The concentrations of GABA and Glu in cancer tissues are significantly higher than those in normal tissue.

Glycyl-glutamine-supplemented long-term total parenteral nutrition selectively improves structure and function in heterotopic small-bowel autotransplantation in the pig.

Marked atrophy and impaired absorptive and barrier function occur in transplanted small intestinal graft during total parenteral nutrition (TPN), TPN is required by all the patients after small bowel transplantation (SBT). Glutamine (Gln) is a conditional indispensable amino acid that is not included in regimens for parenteral nutrition because of its chemical instability in aqueous solution. Glutamine-containing dipeptide, however, is heat-stable. With this study, we determine whether the glycyl-glutamine-supplemented long-term TPN improves mucosal structure and function in heterotopic transplanted small intestinal graft in the pig. Ten outbred pigs, randomly divided into two groups, underwent heterotopic small bowel autotransplantation. In the STPN group, the animals received standard TPN without glycyl-glutamine (Gly-Gln) and in the GTPN group, the animals received isonitrogenous (0.3g kg day(-1)) and isocalories (nonprotein calories, 30 kcal kg day(-1)) TPN with Gly-Gln (3% Gln) for 28 days. At the end of TPN, there was no significant difference in the body weight loss between two groups ( P>0.05). The mucosal contents of Gln and protein were significantly higher in the GTPN group than in the STPN group ( P<0.05). The mucosal disaccharidase activities in the homogenate of the graft mucosa of the GTPN group were significantly higher than that of the STPN group ( P<0.05). The villous height, surface area, mucosal thickness were significantly higher in the GTPN group than in the STPN group ( P<0.05). There was no significant difference in crypt depth between the two groups ( P>0.05). These results suggest that glycyl-glutamine-supplemented long-term TPN improves graft mucosal structure in heterotopic autotransplanted small bowel grafts in the pig. Long-term (4 weeks) TPN supplemented with Gln could alleviate small intestinal graft atrophy, but could not completely eliminate atrophy.

Evaluation of various solutions for small bowel graft preservation.

AIM:To elucidate the effect of various solutions for small bowel graft preservation in pigs under hypothermic storage.METHODS:The swine segmental small bowel graft was autotransplanted after it was preserved with lactated Ringer's (LR), Euro-Collins (EC), hyperosmolarity citrate adenine (HC-A) and WMO-1 solutions for 10,18 and 24 hours,respectively.The recipient survival rate, morphological structure, graft mucosal energy substances and Na( +) -K(+) ATPase activity were studied,and graft absorption was estimated with D-xylose absorption test.RESULTS:The morphological study of the grafts preserved with LR or HC-A solution for 10 hours or with EC and WMO-1 solution for 18 hours was normal 6days after operation. Mucosal ATP,total adenine nucleotides (TAN) contents and Na( +) -K(+)ATPase activity of the graft preserved with EC or WMO solution were higher than that of the graft preserved with LR or HC-A solution.Serum level of D-xylose was higher in EC and WMO-1 groups than in LR and HC-A groups when the graft was preserved for 24 hours.CONCLUSION:EC and WMO-1 solutions can preserve the swine small bowel up to 18 hours, which are superior to LR and HC-A solutions.