Management of deep sacral and ischial pressure injuries with free-style local perforator flaps: A D+P+DPD model

BACKGROUND

Previous reports on the treatment of sacral and ischial pressure injuries have not provided clear algorithms for surgical therapies. The objective of this study was to establish a reconstruction algorithm to guide the selection of an ideal free-style perforator flap that can be tailored to the defect in question.

METHODS

We used 23 perforator flaps to reconstruct 14 sacral and 8 ischial defects in 22 patients over 5 years. A reconstruction algorithm system was developed based on the anatomical features of the perforator vessels (diameter, D; pulsatility [++∼+++], P) and their position in the skin island (DPD) (ie, D+P+DPD). A perforator-based propeller flap was applied as the first-line choice; if this plan was not feasible, we applied an altered V-Y advancement model or another second-choice technique.

RESULTS

All flaps survived, and only 1 patient experienced partial wound dehiscence, which healed by secondary intention. After an average follow-up period of 11.2 months, no patient experienced recurrence or infection.

CONCLUSIONS

Free-style perforator flap selection is determined by pressure injury and the desired advantage of a specific approach. The use of free-style perforator-based propeller flaps allows a surgeon to transfer healthy tissue into the defect, shifts the suture line away from the bony prominence, and preserves additional future donor sites. In cases where unexpected variations are encountered, the V-Y advancement model or another technique can be used. The simplified surgical algorithm (D+P+DPD) can provide versatility and reliability, achieve a durable, natural esthetic outcome, and minimize injuries to future donor sites.

A modified perforator-based stepladder V-Y advancement flap in the Achilles tendon area for coverage of larger posterior heel defects

BACKGROUND

Posterior heel defect coverage is challenging because of the paucity of suitable flaps. The traditional local stepladder V-Y advancement flap is recommended only for small defects because of the lack of an axial pedicle. This study reports our experience of using the perforator-based stepladder V-Y advancement flaps in a larger posterior heel defect repair.

METHODS

Twenty-two patients with posterior heel defects were treated with modified perforator-based stepladder V-Y advancement flaps in the Achilles tendon area for 11 years. Sixteen males and six females aged 3-74 years underwent surgery. The defect size, perforator characteristics, flap size, flap movement, sural nerve, lesser saphenous vein, deep fascia, flap survival, and outcome quality were analyzed.

RESULTS

The perforators were found to predominate within two 2-cm intervals: 0-2 cm and 4-6 cm proximal to the tip of the lateral malleolus. Twenty-one perforator-based flaps healed uneventfully, and only one developed tip necrosis on the lower edge, which healed by secondary intention. The maximum distance of distal movement was 5.0 cm for the modified flap in contrast to 2.5 cm for the traditional flap. All flaps allowed adequate and durable reconstruction to be achieved, with excellent contouring after 2-28 months of follow-up.

CONCLUSIONS

The perforator-based stepladder V-Y advancement flap resulted in good outcomes for larger posterior heel defects compared with conventional transfer methods. The flap is a reliable, well-vascularized, sensate, and pliable local flap option that uses similar tissue from adjacent skin for defect repair and creates an internal gliding surface for the Achilles tendon.

[Transcriptomic analysis of tuberculosis peptide-based vaccine MP3RT in humanized mice]

Objective: To identify the differentially expressed genes (DEGs) induced by tuberculosis peptide-based vaccine MP3RT in a humanized mouse model using transcriptomics technology. Methods: This study was conducted from August 2019 to February 2022. We used edgeR software to screen DEGs with a fold change greater than or equal to 1.5 and a P value less than 0.05 as screening conditions. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein interaction network analyses were performed on the screened DEGs. Then, these DEGs were verified by RT-qPCR and statistically analyzed by GraphPad Prism 8 software. Results: A total of 367 DEGs (214 up-regulated and 153 down-regulated) were identified by transcriptomics. Bioinformatics analysis showed that the GO enrichment of the DEGs mentioned above significantly focused on cell metabolism, growth, apoptosis, inflammation, and other terms. In contrast, the KEGG enrichment significantly focused on inflammatory pathways such as the MAPK signaling pathway. Protein interaction network analysis showed that protein Abl1 had the highest aggregation, the highest aggregation coefficient, and the best connectivity. RT-qPCR results showed that gene expressions of cpne4 (t=2.48, P=0.048 0), h2-q10 (t=2.95, P=0.025 6), mef2c (t=2.87, P=0.028 4), cr2 (t=3.23, P=0.178), ablim1 (t=2.91, P=0.033 5), dll1 (t=2.70, P=0.027 3) and ms4a2 (t=3.03, P=0.019 2) genes in the MP3RT group were significantly up-regulated than those in the PBS group, while gene expressions of cd163l1 (t=2.56, P=0.043 0), il1r1 (t=2.91, P=0.022 7) and cd34 (t=2.42, P=0.046 2) genes in the MP3RT group were significantly down-regulated than those in the PBS group. Conclusions: The MP3RT vaccine induced 367 DEGs in humanized mice, which were associated with metabolic and immune responses. Furthermore, we found that p38 MAPK and JNK/MAPK signaling pathways played an important role in the molecular mechanism of the MP3RT vaccine.

Flap failure prediction in microvascular tissue reconstruction using machine learning algorithms

BACKGROUND

Microvascular tissue reconstruction is a well-established, commonly used technique for a wide variety of the tissue defects. However, flap failure is associated with an additional hospital stay, medical cost burden, and mental stress. Therefore, understanding of the risk factors associated with this event is of utmost importance.

AIM

To develop machine learning-based predictive models for flap failure to identify the potential factors and screen out high-risk patients.

METHODS

Using the data set of 946 consecutive patients, who underwent microvascular tissue reconstruction of free flap reconstruction for head and neck, breast, back, and extremity, we established three machine learning models including random forest classifier, support vector machine, and gradient boosting. Model performances were evaluated by the indicators such as area under the curve of receiver operating characteristic curve, accuracy, precision, recall, and F1 score. A multivariable regression analysis was performed for the most critical variables in the random forest model.

RESULTS

Post-surgery, the flap failure event occurred in 34 patients (3.6%). The machine learning models based on various preoperative and intraoperative variables were successfully developed. Among them, the random forest classifier reached the best performance in receiver operating characteristic curve, with an area under the curve score of 0.770 in the test set. The top 10 variables in the random forest were age, body mass index, ischemia time, smoking, diabetes, experience, prior chemotherapy, hypertension, insulin, and obesity. Interestingly, only age, body mass index, and ischemic time were statistically associated with the outcomes.

CONCLUSION

Machine learning-based algorithms, especially the random forest classifier, were very important in categorizing patients at high risk of flap failure. The occurrence of flap failure was a multifactor-driven event and was identified with numerous factors that warrant further investigation. Importantly, the successful application of machine learning models may help the clinician in decision-making, understanding the underlying pathologic mechanisms of the disease, and improving the long-term outcome of patients.

The effect of inhibiting exosomes derived from adipose-derived stem cells via the TGF-β1/Smad pathway on the fibrosis of keloid fibroblasts

Background

The main mechanism of keloid formation is that keloid fibroblasts (KFs) apoptosis is inhibited, leading to excessive proliferation. Transforming growth factor-β1 (TGF-β1) is a key signal molecule in the process of regulating cell fibrosis. This paper discusses the effect of adipose-derived stem cell exosomes (ADSCs-EXO) on the proliferation and apoptosis of KFS and its possible mechanism, in order to provide reference for the clinical intervention of hypertrophic scar.

Methods

ADSCs were isolated and cultured from human adipose tissue, the supernatant was collected, and the exosomes secreted by ADSCs-EXO were extracted by ultracentrifugation. At the same time, KFs were cultured from human keloid tissue to P3 generation, and then divided into four groups: control group, experimental group A, experimental group B and experimental group C. KFs were then cultured with four concentrations of ADSCs-EXO (0, 1, 10, and 100 µg/mL, respectively). After 24 hours, cells in each group were taken to detect the following: proliferation of cells in each group using the cell counting Kit 8 (CCK-8) method, cell migration ability via the Transwell test, cell apoptosis by flow cytometry, collagen synthesis using the hydroxyproline method, messenger ribonucleic acid (mRNA) expression of fibrosis-related genes in each group by real-time fluorescent polymerase chain amplification, and the expression of fibrosis-related proteins in the cells of each group by western blotting.

Results

Compared with the control group, the proliferation rate, migration rate, and collagen synthesis levels in the three experimental groups decreased with the increase of ADSCs-EXO concentration, while the apoptosis rate in the three experimental groups increased with the increase of ADSCs-EXO concentration, and the differences were statistically significant (P<0.05). Also, compared with the control group, the relative mRNA and protein expression of alpha-smooth muscle actin (α-SMA), TGF-β1, and Smad3 in the three groups decreased significantly, while the expression of three kinds of mRNA and protein decreased with the increase of ADSCs-EXO concentration, and the differences were statistically significant (P<0.05).

Conclusions

ADSCs-EXO may inhibit the proliferation and migration, and promote the apoptosis of KFs by inhibiting the expression of the TGF-β1/Smad pathway.

[Clinical application of Acutegastrointestinal injury grading system assocaited with clinical severity outcome in critically ill patients: a multi-center prospective, observational study]

Objective: To investigate the feasibility of utilizing the current acute gastrointestinal injury(AGI) grading system, and explore the association of severity of AGI grade with clinical outcome in critically ill patients. Methods: The adult patients from 14 general ICUs in Zhejiang Province with an expected admission to ICU for at least 24 h were recruited, and all clinical, laboratory, and survival data were prospectively collected. The AGI grade was daily assessed based on GIsymptoms, feeding details and organ dysfunctionon the first week of admission to ICU.The intra-abdominal pressures(IAP) was measured using AbViser device. Results: Of 550 patients enrolled, mean values for age and APACHE Ⅱ score were (64.9±17.2) years and (19.5±7.4), respectively. 456 patients(82.9%) took mechanical ventilation, and 470 patients were identified for AGI. The distribution of AGI grade on the frist day of ICU admission were 50.6%(Ⅰ grade, n=238), 34.2%(Ⅱ grade, n=161), 12.4%(Ⅲ grade, n=58) and 2.8%(Ⅳ, n=13), respectively, while the distribution of the global AGI grade based on the 7-day AGI assessment of ICU admission were 24.5%(Ⅰ grade, n=115), 49.4%(Ⅱ grade, n=232), 20.6%(Ⅲ grade, n=97) and 5.5%(Ⅳ, n=26), respectively. 28- and 60-day mortality rate was 29.3%(n=161) and 32.5%(n=179), respectively. The patients with AGI had a higher 28-(31.1% vs 18.8%, P=0.025) and 60-day survival rate(34.7% vs 20.0%, P=0.01) than those with non-AGI, and also there were positive correlations between AGI grade and 28- and 60-day mortality(P<0.001). Univariate Cox regression analysis showed that age, the source of medicial admission, diabetes mellitus, coronary heart disease, the use of vasoactive drugs, serum creatinine and lactate, mechanical ventilation, APACHE Ⅱ score, the AGI grade in the first day of ICU admission and feeding intolerance within the first week of ICU stay were significantly(P≤0.02) associated with mortality. In multivariate analysis including all these variables, the source of medical admission(χ(2)=4.34, P=0.04), diabete mellitus(χ(2)=3.96, P=0.05), the use of vasoactive drugs(χ(2)=6.55, P=0.01), serum lactate(χ(2)=4.73, P=0.03), the global AGI grade in the 7-day of ICU admission(χ(2)=7.10, P=0.008), and APACHE Ⅱ score(χ(2)=12.1, P<0.001) remained independent predictors for 60-day mortality.In the further subgroup analysis including 402 patients with 7-day survival, the feeding intolerance within the first week of ICU stay could provide independent and incremental prognostic value of 60-day mortality wtih increased χ(2)value of Cox regression model(χ(2)=52.2 vs 41.9, P=0.007) . Conclusion: The AGI grading system is useful for identifying the severity of gastrointestinal dysfunction, and could be used as a strong predictor of impaired outcome. The results provide evidence to support that feeding intolerance within 7 days of admission to ICU was an independent determinant of mortality.

[Morphological characteristics and phenotypic analysis of multiple morphological abnormalities in sperm flagella]

Objective: To analyze the sperm morphological characteristics of multiple morphological abnormalities of the sperm flagella (MMAF), and to analyze their common features and subtypes. Methods: Twenty-eight patients with abnormal morphology of flagella were analyzed by semen analysis. The morphological characteristics were analyzed by scanning electron microscopy and transmission electron microscopy. Histological observation of one case of testicular tissue was performed. Results: Of the 28 patients, only 13 patients (46.4%) had motile spermatozoa, 12 of which had a sperm motility rate of <10% and a sperm survival rate of 9.0%-80.0%. Under light and scanning electron microscope, sperm with absent, short, coiled, bent and irregular width flagella or their combinations were observed. Transmission electron microscopy showed structural abnormalities of sperm fibrous sheath, mitochondrial sheath. Loss rate of central microtubule was 41.4%-84.6%. The semen of the 2 patients with the absence or presence of the kinetic protein arm and both the inner and lateral motilin arms missing had no motile spermatozoa. There was no statistically significant difference in the proportion of flagellar malformations between the two groups of patients (without motile sperm vs with motile spermatozoa). Conclusion: MMAF is a kind of sperm flagella specific abnormalities. Initially diagnosis can be carried out using light microscopy. Clear diagnosis could be conduct using transmission electron microscopy, and the central microtubule loss of the sperm could be seen as the main feature of the flagella abnormalities. Through the morphological analysis and research, MMAF could be precisely classified, which provide a strong basis for the diagnosis.

[Study on the kidney impairment and expressions of FGF21 from a rat model of vascular calcification]

Objective: To investigate the injury and pathological changes of kidney in a rat model of aortic vascular calcification and to explore the expressions of fibroblast growth factor 21 (FGF21). Methods: A total of 14 Spraugue Dawley (SD) rats were randomly divided into two groups: control group and vitamin D3+ nicotine (VDN) group, with 7 rats in each group.The rats in VDN group received vitamin D3 and nicotine to induce vascular calcification.The content of serum creatinine was determined by sarcosine oxidase method.Alkaline phosphatases (ALP) activity was detected by ALP detection kit.The protein levels of FGF21 were measured by radioimmunoassay (RIA). The structure of kidney was observed by hematoxylin and eosin staining. Results: The serum concentration of creatinine in VDN group was significantly higher than control group[(34.00±4.69) vs (27.17±5.38) μmol/L, P<0.05], and the renal pathological changes in VDN group were more apparent. ALP activity in VDN group was significantly higher than that in control group[(62.59±22.62) vs (29.89±11.78) U/g, P<0.05]. Expression of FGF21 in VDN group increased obviously, compared with that in control group[(0.583±0.340) vs (0.207±0.105) ng/mg, P<0.05]. Meanwhile, the elevated levels of FGF21 were positively correlated with up-regulation of ALP in calcified kidneys (r=0.878, P<0.05). Conclusions: Flushing dose of vitamin D3 and nicotine can induce the change of pathology and function of the kidney.Meanwhile, the expression of FGF21 in kidney up-regulated significantly, suggesting that FGF21 may be involved in the occurrence and development of vascular calcification and subsequent kidney injury.

Sensitivity of tissue properties derived from MRgFUS temperature data to input errors and data inclusion criteria: ex vivo study in porcine muscle

This study evaluates the sensitivity of two magnetic resonance-guided focused ultrasound (MRgFUS) thermal property estimation methods to errors in required inputs and different data inclusion criteria. Using ex vivo pork muscle MRgFUS data, sensitivities to required inputs are determined by introducing errors to ultrasound beam locations (r error  =  -2 to 2 mm) and time vectors (t error  =  -2.2 to 2.2 s). In addition, the sensitivity to user-defined data inclusion criteria is evaluated by choosing different spatial (r fit  =  1-10 mm) and temporal (t fit  =  8.8-61.6 s) regions for fitting. Beam location errors resulted in up to 50% change in property estimates with local minima occurring at r error  =  0 and estimate errors less than 10% when r error  <  0.5 mm. Errors in the time vector led to property estimate errors up to 40% and without local minimum, indicating the need to trigger ultrasound sonications with the MR image acquisition. Regarding the selection of data inclusion criteria, property estimates reached stable values (less than 5% change) when r fit  >  2.5  ×  FWHM, and were most accurate with the least variability for longer t fit. Guidelines provided by this study highlight the importance of identifying required inputs and choosing appropriate data inclusion criteria for robust and accurate thermal property estimation. Applying these guidelines will prevent the introduction of biases and avoidable errors when utilizing these property estimation techniques for MRgFUS thermal modeling applications.

Electroacupuncture decreases the urinary bladder pressure in patients with acute gastrointestinal injury

The present study investigates the effects of electroacupuncture (EA) on urinary bladder pressure (UBP) in patients with acute gastrointestinal injury (AGI). Twenty patients with AGI admitted to the First Hospital of Jiaxing intensive care unit from December 2011 to June 2013 were evaluated. Conventional group patients (n = 10) were administered moderate enteral nutritional support, and electroacupuncture group patients (n = 10) were administered enteral nutritional support followed by EA at bilateral Zusanli (ST-36), Shangjuxu (ST-37), Hegu (LI-4), and QuChi (LI-11) acupoints. UBP was then measured every 6 h and the serum creatinine once daily for 7 days. There were no statistically significant patient demographic differences in the study groups (P > 0.05). The initial UBP of both patient groups was ≥12 mmHg. On days 6 and 7, the UBP significantly decreased in the EA group compared to the conventional group (P < 0.05). The serum creatinine concentration on day 7 was significantly lower in the EA group than in the conventional group (P < 0.05). Based on these results, electroacupuncture contributed to gastrointestinal motility recovery in patients with AGI. This procedure may reduce UBP and provide organ-protective effects in AGI patients.

Genetic diversity and differentiation of the endangered and endemic species Sauvagesia rhodoleuca in China as detected by ISSR analysis

Sauvagesia rhodoleuca (Ochnaceae) is an endangered plant that is endemic to southern China. The levels of genetic variation and patterns of population structure in S. rhodoleuca were investigated using inter-simple sequence repeat markers. Eleven primers were used to amplify DNA samples from 117 individuals, and a total of 92 loci were detected. Our results indicated that genetic diversity was quite low both at the species level (percentage of polymorphic bands (PPB) = 41.30%, Nei's gene diversity (h) = 0.1331, and Shannon information index (I) = 0.2028) and the population level (PPB = 16.30-28.26%, h = 0.0496-0.1012, and I = 0.0756-0.1508). A high level of genetic differentiation among populations was detected based on Nei's genetic diversity analysis (0.4344) and analysis of molecular variance (47.03%). The low genetic diversity within population and high population differentiation of S. rhodoleuca were assumed to result largely from limited gene flow, genetic drift, inbreeding, and clonal growth. Conservation strategies for this endangered species are proposed based on the genetic data.

First Report of Tomato chlorosis virus in China

In October 2012, a severe yellowing disease was found on greenhouse and plastic house tomato (Solanum lycopersicum) plants in Beijing, China. The disease incidence varied from 5 to 80% in each of six fields across Haidian and Daxing districts. The lower leaves showed symptoms of interveinal chlorosis, leaf brittleness, and limited brown necrotic flecks, similar to symptoms induced by Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV) (two members of genus Crinivirus, family Closteroviridae) (4). A large number of whiteflies (Bemisia tabaci) were also observed. Leaf samples were taken from eight symptomatic and two asymptomatic tomato plants in two plastic houses in the Haidian district and total RNA was isolated from the 10 samples using TRIzol reagent (Tiangen, Beijing, China). Nested reverse transcription (RT)-PCR was performed to test the presence of ToCV and TICV with degenerate primers HS-11 and HS-12 and specific primers ToC-5/ToC-6 or TIC-3/TIC-4 for ToCV or TICV, respectively (1). With ToCV primers, a 463-bp specific fragment was amplified from eight symptomatic samples but not from two asymptomatic samples, and there was no amplification with TICV primers from any sample. Sequence analysis of the amplified fragment showed 99% nucleotide sequence identity with the heat shock protein 70 homolog (HSP70h) gene of ToCV isolates from Japan (GenBank Accession No. AB513442), Spain (DQ136146), Florida (AY903448), and Greece (EU284744). The presence of ToCV was confirmed by amplification of a 848-bp fragment covering the coat protein (CP) gene of ToCV with primers CP-F (5'-GAATCTTTTAGAAGCTTTGGTTTAAGG-3') and CP-R (5'-GATCCTCTTGATCCTCATAGATTTC-3') (3). The CP had 97 to 99% amino acid sequence identity to the above-mentioned four ToCV isolates. A sequence of the CP gene obtained from one isolate was deposited at GenBank (KC311375). Additionally, virions were isolated from 25 g of symptomatic samples followed Klaassen's method (2) and their lengths were estimated to be about 800 to 850 nm by transmission electronic microscopy To our knowledge, this is the first report of ToCV on tomato in mainland China. Tomato is one of the most widely cultivated crops in China and the spread of ToCV in China may cause significant economic losses. Further information on the prevalence and incidence of ToCV is required to assess the potential impact of this virus. References: (1) C. I. Dovas et al. Plant Dis. 86:1345, 2002. (2) V. A. Klaassen et al. J. Gen. Virol. 75:1525, 1994. (3) H. Tomoki et al. J. Gen. Plant Pathol. 76:168, 2010. (4) G. C. Wisler et al. Phytopathology 88:402, 1998.

Absence of SH2B3 mutation in nonobese diabetic mice

Type 1 diabetes is a chronic progressive autoimmune disease characterized by mononuclear cell infiltration, with subsequent destruction of insulin-producing β-cells. Studies have identified strong associations between type 1 diabetes and several chromosome regions, including 12q24. Association between type 1 diabetes and 12q24 arises from SNP rs3184504; rs3184504 is a nonsynonymous SNP in exon 3 of SH2B3 (also known as LNK). Nonobese diabetic (NOD) mice recapitulate many aspects of the pathogenesis of type 1 diabetes in humans and are therefore frequently used in studies addressing the cellular and molecular mechanisms of this disease. It is of interest to know whether there is a similar mutation of SH2B3 in NOD mice. We found that the SH2B3 mutation is absent in NOD mice. To our knowledge, this is the first report of the sequence and the protein levels of SH2B3 in NOD mice.

A rare Y chromosome constitutional rearrangement: a partial AZFb deletion and duplication within chromosome Yp in an infertile man with severe oligoasthenoteratozoospermia

We report a case of an infertile man with severe oligoasthenoteratozoospermia with a partial azoospermia factor b (AZFb) deletion and duplication region within chromosome Yp11.2. The hormonal profile was normal for serum concentrations of follicle-stimulating hormone, luteinizing hormone, testosterone and oestradiol. The patient, who showed a 46,XY karyotype, had an approximate 2.4 Mb inherited duplication region in Yp11.2 and a de novo partial AZFb deletion, which spanned 5.25 Mb including eight protein coding genes and four non-coding transcripts, but did not remove the RBMY gene family. Both proximal and distal breakpoints of the deletion were outside any palindromic region or inverted repeat sequence and intra-chromosomal non-allelic homologous recombination could not have been the deletion mechanism. The partial AZFb deletion in our case diminished sperm production, but did not completely extinguish spermatogenesis. Considering severe oligozoospermia, spermatozoa in the patient's ejaculate were used for intracytoplasmic sperm injection, resulting in two twin pregnancies.

Additive actions of the cannabinoid and neuropeptide Y systems on adiposity and lipid oxidation

AIMS

Energy homeostasis is regulated by a complex interaction of molecules and pathways, and new antiobesity treatments are likely to require multiple pharmacological targeting of anorexigenic or orexigenic pathways to achieve effective loss of excess body weight and adiposity. Cannabinoids, acting via the cannabinoid-1 (CB1) receptor, and neuropeptide Y (NPY) are important modulators of feeding behaviour, energy metabolism and body composition. We investigated the interaction of CB1 and NPY in the regulation of energy homeostasis, hypothesizing that dual blockade of CB1 and NPY signalling will induce greater weight and/or fat loss than that induced by single blockade of either system alone.

METHODS

We studied the effects of the CB1 antagonist Rimonabant on food intake, body weight, body composition, energy metabolism and bone physiology in wild-type (WT) and NPY knockout (NPY(-/-)) mice. Rimonabant was administered orally at 10 mg/kg body weight twice per day for 3 weeks. Oral Rimonabant was delivered voluntarily to mice via a novel method enabling studies to be carried out in the absence of gavage-induced stress.

RESULTS

Mice with dual blockade of CB1 and NPY signalling (Rimonabant-treated NPY(-/-) mice) exhibited greater reductions in body weight and adiposity than mice with single blockade of either system alone (Rimonabant-treated WT or vehicle-treated NPY(-/-) mice). These changes occurred without loss of lean tissue mass or bone mass. Furthermore, Rimonabant-treated NPY(-/-) mice showed a lower respiratory exchange ratio than that seen in Rimonabant-treated WT or vehicle-treated NPY(-/-) mice, suggesting that this additive effect of dual blockade of CB1 and NPY involves promotion of lipid oxidation. On the other hand, energy expenditure and physical activity were comparable amongst all treatment groups. Interestingly, Rimonabant similarly and transiently reduced spontaneous and fasting-induced food intake in WT and NPY(-/-) mice in the first hour after administration only, suggesting independent regulation of feeding by CB1 and NPY signalling. In contrast, Rimonabant increased serum corticosterone levels in WT mice, but this effect was not seen in NPY(-/-) mice, indicating that NPY signalling may be required for effects of CB1 on the hypothalamo-pituitary-adrenal axis.

CONCLUSIONS

Dual blockade of CB1 and NPY signalling leads to additive reductions in body weight and adiposity without concomitant loss of lean body mass or bone mass. An additive increase in lipid oxidation in dual CB1 and NPY blockade may contribute to the effect on adiposity. These findings open new avenues for more effective treatment of obesity via dual pharmacological manipulations of the CB1 and NPY systems.

Peripheral neuropeptide Y Y1 receptors regulate lipid oxidation and fat accretion

OBJECTIVE

Neuropeptide Y and its Y receptors are important players in the regulation of energy homeostasis. However, while their functions in feeding regulation are well recognized, functions in other critical aspects of energy homeostasis are largely unknown. To investigate the function of Y1 receptors in the regulation of energy homeostasis, we examined energy expenditure, physical activity, body composition, oxidative fuel selection and mitochondrial oxidative capacity in germline Y1(-/-) mice as well as in a conditional Y1-receptor-knockdown model in which Y1 receptors were knocked down in peripheral tissues of adult mice.

RESULTS

Germline Y1(-/-) mice of both genders not only exhibit a decreased respiratory exchange ratio, indicative of increased lipid oxidation, but interestingly also develop late-onset obesity. However, the increased lipid oxidation is a primary effect of Y1 deletion rather than secondary to increased adiposity, as young Y1(-/-) mice are lean and show the same effect. The mechanism behind this is likely because of increased liver and muscle protein levels of carnitine palmitoyltransferase-1 (CPT-1) and maximal activity of key enzymes involved in beta-oxidation; beta-hydroxyacyl CoA dehydrogenase (betaHAD) and medium-chain acyl-CoA dehydrogenase (MCAD), leading to increased mitochondrial capacity for fatty acid transport and oxidation. These effects are controlled by peripheral Y1-receptor signalling, as adult-onset conditional Y1 knockdown in peripheral tissues also leads to increased lipid oxidation, liver CPT-1 levels and betaHAD activity. Importantly, these mice are resistant to diet-induced obesity.

CONCLUSIONS

This work shows the primary function of peripheral Y1 receptors in the regulation of oxidative fuel selection and adiposity, opening up new avenues for anti-obesity treatments by targeting energy utilization in peripheral tissues rather than suppressing appetite by central effects.

Production of very-high-amylose potato starch by inhibition of SBE A and B

High-amylose starch is in great demand by the starch industry for its unique functional properties. However, very few high-amylose crop varieties are commercially available. In this paper we describe the generation of very-high-amylose potato starch by genetic modification. We achieved this by simultaneously inhibiting two isoforms of starch branching enzyme to below 1% of the wild-type activities. Starch granule morphology and composition were noticeably altered. Normal, high-molecular-weight amylopectin was absent, whereas the amylose content was increased to levels comparable to the highest commercially available maize starches. In addition, the phosphorus content of the starch was increased more than fivefold. This unique starch, with its high amylose, low amylopectin, and high phosphorus levels, offers novel properties for food and industrial applications.

Regulation of brain G-protein go by Alzheimer's disease gene presenilin-1

To investigate a possible association between G-proteins and presenilin-1 (PS-1), a series of glutathione S-transferase-fusion proteins containing portions of PS-1 were prepared and used in vitro in binding experiments with tissue and recombinant G-proteins. The results demonstrate that the 39 C-terminal amino acids of PS-1 selectively bind the brain G-protein, Go. Addition of guanosine 5'-3-O-(thio)triphosphate promoted Go dissociation from PS-1, indicating that this domain mimics the function of G-protein-coupling domains found in receptors. The 39-amino acid synthetic polypeptide activated Go in a magnesium ion-dependent manner. Physical interaction of full-length PS-1 and Go was also demonstrated. Following transfection of Goalpha and N-terminally FLAG-tagged PS-1 in COS-7 cells, Go was immunoprecipitated by FLAG antibodies. In addition, endogenous PS-1 and Goalpha were colocalized immunocytochemically in human glioma cell lines. The results indicate that PS-1 regulates Go activities in living cells.

Affinity chromatography of trypsin using chitosan as ligand support

Chitosan beads were prepared for use as affinity adsorbent carrier. The affinity ligand, chicken ovomucoid, was immobilized on the chitosan via a cross-linker, glutaraldehyde. The results showed that 60 mg chicken ovomucoid could be immobilized on l g chitosan, and the maximum binding capacity for trypsin was about 8.10(4) U/g dry adsorbent. The procedure for preparing the chitosan-based affinity adsorbents was much safer and simpler than when a Sepharose-based matrix was the support. Columns packed with the affinity adsorbents were employed for trypsin chromatography. The experimental results revealed that the affinity adsorbents possessed good mechanical strength and storage stability and could be also operated repeatedly. Chitosan was suitable for use as an affinity adsorbent support for laboratory-scale and large-scale purification.

[Anti-virus effect of aralosides]

The result showed that the anti-virus effect of aralosides on infections with poliovirus II, ECHO delta virus, adenovirus II, herpes simplex virus I, coxsackie B3 virus and coxsackie A16 virus was remarkable. Aralosides could inhibit the development of cytopathic effect (CPE) and protect cultural cells from being infected with the above viruses.

Diagnostic value of serum gamma-glutamyl transferase isoenzyme for hepatocellular carcinoma: a 10-year study

Serum gamma-glutamyl transferase (GGT) was separated into nine to 11 isoenzyme bands (designated as GGT I-XI) by vertical slab electrophoresis on polyacrylamide gradient gel. The diagnostic value of GGT isoenzyme II (GGT II) for hepatocellular carcinoma (HCC) was studied, and the results were as follows: 1) GGT II was positive in 90% of 90 cases of HCC, and negative in most patients with acute and chronic viral hepatitis, extrahepatic tumors, in pregnant women, and in healthy controls; 2) the positive rate of GGT II assay was higher than that of alkaline phosphatase isoenzyme I (ALP I), alpha-fetoprotein (AFP), and alpha 1-antitrypsin (AAT) in 101 cases of HCC. In cases in which the AFP was greater than 50 ng/ml or less than 50 ng/ml, the positive rates of GGT II were 70.8% and 75-100%, respectively; 3) of 14 cases of small-size HCC, the positive rate of GGT II was 78.6%, which was higher than that of AFP (50%), AAT (28.6%), and ALP I (0%); 4) of 62 cases that were false-positive for GGT II assay, 24.2% developed into HCC during a follow-up of 2.1-20 months. In subjects with persistent and recurrent positivity of GGT II, 86.7% and 22.2%, respectively, developed HCC. No patient with temporal positivity of GGT II developed HCC. The results show that GGT II can be applied as an additional marker for HCC, and is valuable not only for the diagnosis of clinical HCC, but for the detection of small or subclinical HCC. Periodic follow-up with assay of GGT II in patients at high risk for HCC may predict the development of hepatoma.

Leaching of amylose from wheat and corn starch

Wheat starch gave a 21% yield (based on starch) of amylose (AM) when leached at 3% solids under mild agitation, and at a heating rate of 10 degrees C/min to 95 degrees C followed by holding at least 10 min. Annealing wheat starch prior to leaching at 95 degrees C or using a heating rate of 1 degrees C/min during leaching, increased AM yield from 21% to 23% at 3.0% starch solids, and 8% to 16% at 4.5% starch solids. At 0.5% solids, almost all wheat AM (29% of starch) was solubilized into the continuous phase at 95 degrees C, but only one-half of the lipid in the starch co-leached with AM. Corn starch behaved similarly to wheat starch during leaching below 1.5% starch solids, while at 3.0% almost 40% more AM was obtained from wheat than corn starch. Wheat AM molecules isolated by leaching were larger than those obtained by crystallizing its n-butanol complex, and they gave a different size-distribution as evidenced by high-performance size-exclusion chromatography. A triangular phase diagram was useful in depicting the overall process of leaching AM from starch. The critical concentrations of wheat (5.4%) and corn (5.2%) starches were determined using phase diagrams.

Reappraisal of diagnostic significance of a hepatoma-specific band of serum gamma-glutamyl transferase

The hepatoma-specific band of serum gamma-glutamyl transferase II (GGT II) and other three markers were evaluated in 77 patients with primary hepatocellular carcinoma (PHC). The positive rate of GGT II (87%) was much higher than that of the increased alpha-fetoprotein (AFP greater than or equal to 400 ng/ml, 54.5%), the increased alpha-1-antitrypsin (AAT greater than or equal to 400 mg/dl, 64.9%) and alkaline phosphatase isoenzyme I (ALP I, 13.0%). In patients with AFP less than 400 ng/ml, the positive rate of GGT II was 95.2%, higher than that of ALP I (22.8%) and AAT (60.0%). The positive rate of GGT II was positively correlated to the volume of PHC (r = 0.324, P less than 0.05), but even in patients with small PHC (less than or equal to 65 cm3), the positive rate of GGT II (78.6%) was higher than that of AFP (50.0%) and AAT (28.6%). The ALP I positivity was only seen in patients with larger PHC. Follow-up study showed that GGT II, like AFP, might occur before liver tumor could be detected by B-mode ultrasonography and computerized tomography. Therefore, GGT II is a valuable marker of PHC, especially in patients whose AFP was negative or slightly increased; GGT II may be useful for relatively early diagnosis of PHC.

The diagnostic value of a hepatoma-specific band of serum gamma-glutamyl transferase

Using a vertical slab electrophoretic apparatus loaded with polyacrylamide stage gel plate, we observed a total of II bands of gamma-glutamyl transferase (EC 2.3.2.2,GGT) on a gel plate and designated these GGT I-XI by order of distance beginning at the positive pole. Positive GGT II was found in 81 (90%) of 90 cases of primary hepatic carcinoma (PHC), in 9(90%) of 10 cases of secondary hepatic carcinoma (SHC), and in only 4 (3.1%) of a total of 128 cases of acute and chronic liver disease. There was one case with positive GGT II among 45 cases of cancer of ampulla of Vater, but the possibility of hepatic metastasis could not be excluded. No GGT II was found in a total of 250 healthy persons and 21 pregnant women. PHC patients with negative alpha-fetoprotein (AFP) had a positive GGT II rate of 84.6%, whereas in those with negative GGT II the positive rate for AFP was only 44.4%.