A Multifunctional, Tough, Stretchable, and Transparent Curcumin Hydrogel with Potent Antimicrobial, Antioxidative, Anti-inflammatory, and Angiogenesis Capabilities for Diabetic Wound Healing.

The treatment of diabetic chronic wounds is still faced with great challenges, mainly due to wound infection, excessive inflammation, and peripheral vascular disease in the wound area. Therefore, it is of great importance to develop a novel multifunctional hydrogel with high efficiency to accelerate diabetic wound healing. Curcumin (Cur), a Chinese herbal, has shown great potential in enhancing the healing of diabetic chronic wounds because of its immunomodulatory and pro-angiogenic properties. However, its low aqueous solubility, poor bioavailability, and chemical instability have limited its clinical applications. To address these current bottlenecks, novel poly(vinyl alcohol) (PVA)-chitosan (CS)/sodium alginate (SA)-Cur (PCSA) hydrogels were prepared for the first time, and they demonstrated all of the above intriguing performances by the Michael addition reaction of CS and Cur. PCSA hydrogels show multiple dynamic bonds, which possess strong mechanical properties (tensile stress: ∼0.980 MPa; toughness: ∼258.45 kJ/m3; and compressive strength: ∼7.38 MPa at strain of 80%). These intriguing performances provided an optimal microenvironment for cell migration and proliferation and also promoted the growth of blood vessels, leading to early angiogenesis. Importantly, the experimental results demonstrated that PCSA hydrogels can effectively transform pro-inflammatory M1 macrophages into anti-inflammatory M2 macrophages without the need for additional ingredients in vitro. Benefiting from these characteristics, a full-thickness diabetic wound in a rat model demonstrated that PCSA hydrogels can effectively accelerate wound healing via ROS-scavenging, downregulation of IL-1ß, and upregulation of CD31 expression, resulting in angiogenesis and collagen deposition. This strategy not only provides a simple and safe Cur-based hydrogel for diabetic wound healing but also highlights the significant potential for the development of high-performance biomaterials for promoting diabetic wound healing using traditional Chinese medicine.

Insulin resistance levels predicted metabolic improvement and weight loss after metabolic surgery in Chinese patients with type 2 diabetes.

BACKGROUND: The causes for failure of metabolic improvement and inadequate weight loss after metabolic surgery (MS) in Chinese patients with type 2 diabetes (T2D) have not been fully elucidated. The effect of insulin resistance (IR) on the outcome of T2D, hypertension, hyperlipidemia, and obesity after MS in Chinese patients with T2D and a body mass index (BMI) of 25-32.5 kg/m2 warrants further study. OBJECTIVES: Patients with T2D and a BMI of 25-32.5 kg/m2 who underwent MS between July 2019 and June 2021 were included. SETTING: University hospital, China. METHODS: IR levels were evaluated with the glucose disposal rate (GDR). Improvement of T2D, hypertension, and hyperlipidemia was assessed with the composite triple endpoint (CTEP), and weight loss was assessed with the percent of total weight loss (%TWL). Partial correlation analysis, binary logistic regression analysis, multiple linear regression analysis, receiver operating characteristic curve (ROC) analysis, and subgroup analysis were used to analyze the relationship between the CTEP, %TWL at 1 year postoperative, and GDR preoperative. RESULTS: This study analyzed the data of 51 patients with T2D and a BMI of 25-32.5 kg/m2 (30 men and 21 women) with a mean preoperative GDR of 3.72 ± 1.48 mg/kg/min. Partial correlation coefficients between CTEP, %TWL, and GDR were .303 (P = .041) and .449 (P = .001), respectively. The preoperative GDR was significantly positively correlated with CTEP (OR = 1.610, P = .024) and %TWL (ß = 1.38, P = .003). The preoperative GDR predicted cutoff values of 4.36 and 5.35 mg/kg/min for CTEP attainment and %TWL ≥ 20%, respectively. CONCLUSION: IR levels predicted metabolic improvement and weight loss 1 year after MS in Chinese patients with T2D and a BMI of 25-32.5 kg/m2.

Clinical factors associated with remission of obese acanthosis nigricans after laparoscopic sleeve gastrectomy: a prospective cohort study.

BACKGROUND: Acanthosis nigricans (AN) involves skin hyperpigmentation in body folds and creases. Obesity-associated AN (OB_AN) is the most common type of AN. The skin condition of obese patients with AN can be improved through bariatric surgery, such as laparoscopic sleeve gastrectomy (LSG), after weight loss. However, the contributing factors to the remission of AN after surgery are still not fully determined. The authors aimed to assess the metabolic and pathological factors associated with remission of AN following LSG in obese individuals. METHODS: The study included 319 obese patients who underwent LSG at our hospital. The subjects were divided into obesity (OB) only (OB, n =178) or OB with AN (OB_AN, n =141) groups. The basic clinical and metabolic indices and the dermatological features via reflectance confocal microscopy and histology were collected from patients prior to and after LSG. RESULTS: OB_AN patients had higher fasting plasma glucose, homeostatic model assessment for insulin resistance, and testosterone levels than OB patients. LSG could significantly improve the biochemical and histopathological features of OB_AN patients. The remissive rate of OB_AN patients was about 86.5% (122 out of 141) after surgery. The remission of OB_AN skin lesions was positively correlated with testosterone levels ( P <0.01). In addition, there was a significant positive correlation between changes in AN scores and epidermal thickness and skin pigmentation scores after surgery ( P <0.01). CONCLUSION: The remissive rate of OB_AN after LSG is associated with improved testosterone levels and reduced epidermal thickness and skin pigmentation levels.

Effect of laparoscopic sleeve gastrectomy on mobilization of site-specific body adipose depots: a prospective cohort study.

BACKGROUND: Effect of bariatric surgery on mobilization of site-specific body adipose depots is not well investigated. Herein, the authors conducted a prospective cohort study to assess whether bariatric surgery can differentially affect specific fat storage pools and to further investigate correlations between site-specific fat mobilization and clinical outcomes. MATERIALS AND METHODS: In this single-centre prospective cohort study, 49 participants underwent laparoscopic sleeve gastrectomy (LSG) from 24 May 2022 to 20 October 2022 and underwent MRI to estimate subcutaneous fat area, visceral fat area (VFA), hepatic and pancreatic proton density fat fraction (PDFF) at baseline and 3 months after surgery. The protocol for this study was registered on clinicaltrials.gov. RESULTS: Among 49 patients who met all inclusion criteria, the median [interquartile range (IQR)] age was 31.0 (23.0-37.0) years, the median (IQR) BMI was 38.1 (33.7-42.2) kg/m 2 and 36.7% were male. Median (IQR) percentage hepatic PDFF loss was the greatest after bariatric surgery at 68.8% (47.3-79.7%), followed by percentage pancreatic PDFF loss at 51.2% (37.0-62.1%), percentage VFA loss at 36.0% (30.0-42.4%), and percentage subcutaneous fat area loss at 22.7% (17.2-32.4%) ( P <0.001). By calculating Pearson correlation coefficient and partial correlation coefficient, the positive correlations were confirmed between change in VFA and change in glycated haemoglobin ( r =0.394, P =0.028; partial r =0.428, P =0.042) and between change in hepatic PDFF and change in homoeostatic model assessment of insulin resistance ( r =0.385, P =0.025; partial r =0.403, P =0.046). CONCLUSIONS: LSG preferentially mobilized hepatic fat, followed by pancreatic fat and visceral adipose tissue, while subcutaneous adipose tissue was mobilized to the least extent. Reduction in visceral adipose tissue and hepatic fat is independently associated with the improvement of glucose metabolism after LSG.

Effects of Sleeve Gastrectomy on Patients with Obesity and Polycystic Ovary Syndrome: a Meta-analysis.

PURPOSE: This study aimed to evaluate the efficacy of sleeve gastrectomy (SG) on patients with obesity and polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: We searched PubMed, Embase, Cochrane Library, and Web of Science to identify relevant studies published prior to December 2, 2022. Meta-analysis was performed on menstrual irregularity, total testosterone, sex hormone-binding globulin (SHBG), anti-Mullerian hormone (AMH), glucolipid metabolism indicators, and body mass index (BMI) following SG. RESULTS: Six studies and 218 patients were included in the meta-analysis. Following SG, menstrual irregularity significantly decreased (odds ratio [OR] 0.03; 95% confidence intervals [CIs], 0.00-0.24; P=0.001). Additionally, SG can lower total testosterone levels (MD -0.73; 95% CIs -0.86-0.60; P< 0.0001), as well as BMI (MD -11.59; 95% CIs -13.10-10.08; P<0.0001). A significant increase was observed in the levels of SHBG and high-density lipoprotein (HDL) after SG. In addition to reducing fasting blood glucose, insulin, triglycerides (TG), and low-density lipoprotein levels, SG significantly reduced low-density lipoprotein levels as well. CONCLUSIONS: Following SG, we firstly demonstrated significant improvements in menstrual irregularity, testosterone and SHGB levels, glycolipid metabolism indicators, and BMI. Therefore, SG may be considered as a new option for the clinical treatment of patients with obesity and PCOS.

Large Versus Small Gastric Pouch for Roux-en-Y Gastric Bypass in Individuals With Type 2 Diabetes and a Body Mass Index < 35 kg/m2: Six-Year Outcomes.

Background: Roux-en-Y gastric bypass (RYGB) results in extraordinary weight loss and glycemic control outcomes for patients with obesity; however, the effect of gastric pouch size is still unclear, and the reported results are contradictory. Additionally, long-term data on type 2 diabetes (T2D) patients with low body mass index (BMI) are sparse. This study was to assess the effect of 6-year outcomes in Chinese patients with T2D and a BMI < 35 kg/m2 who underwent RYGB with gastric pouches of different sizes. Methods: A retrospective cohort study was performed. There were 42 patients in the large gastric pouch group (L) and 53 patients in the small gastric pouch group (S). Baseline demographic history, pre- and postoperative BMI, waist circumference, and glucose- and lipid metabolism-related indicators were compared. Results: Assessments were completed in 100%, 100%, 93.6%, and 89.4% of patients at baseline, 1 year, 3 years, and 6 years, respectively. At 6 years, the changes in BMI and fasting plasma glucose were greater in the S group (-4.25 ± 0.51 kg/m2 and -4.58 ± 0.73 mmol/l) than in the L group (-2.06 ± 0.48 kg/m2 and -2.64 ± 0.61 mmol/l). The independent predictors of complete remission of T2D were preoperative BMI and the size of the gastric pouch. A large gastric pouch was associated with a higher risk for marginal ulcers. Conclusions: A small gastric pouch results in better weight loss and glycemic control. High preoperative BMI and a small gastric pouch are associated with better T2D remission rates. A large gastric pouch leads to a higher incidence of marginal ulcers.

Insulin Resistance Remission Following Laparoscopic Roux-en-Y Gastric Bypass and Laparoscopic Sleeve Gastrectomy in Chinese Type 2 Diabetes Mellitus Patients With a Body Mass Index of 27.5-32.5 kg/m2.

Background: Insulin resistance (IR) is closely associated with the pathogenesis of type 2 diabetes mellitus (T2DM). However, remission of insulin sensitivity after bariatric surgery in patients with T2DM and a body mass index (BMI) of 27.5-32.5 kg/m2 has not been fully elucidated. Methods: Thirty-six T2DM patients with a BMI of 27.5-32.5 kg/m2 were prospectively consecutively recruited for laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG). Hyperinsulinemic euglycemic clamp, oral glucose tolerance test (OGTT), and other indicators were tested at baseline and 6 months postoperative. Glucose disposal rate (GDR), time to reach euglycemia, homeostatic model assessment of IR, quantitative insulin sensitivity check index (QUICKI), triglyceride glucose (TyG) index, 30-min insulinogenic index (IGI30), and disposition index (DI) were calculated at baseline and 6 months after surgery. The criterion for remission in T2DM patients was the achievement of the triple composite endpoint. Results: Anthropometric and glucolipid metabolism parameters significantly improved following surgery. The GDR increased significantly from baseline to 6 months after LRYGB (from 4.28 ± 1.70 mg/kg/min to 8.47 ± 1.89 mg/kg/min, p < 0.0001) and LSG (from 3.18 ± 1.36 mg/kg/min to 7.09 ± 1.69 mg/kg/min, p < 0.001). The TyG index decreased after surgery (RYGB group, from 9.93 ± 1.03 to 8.60 ± 0.43, p < 0.0001; LSG group, from 10.04 ± 0.79 to 8.72 ± 0.65, p = 0.0002). There was a significant reduction in the IGI30 (RYGB group, from 2.04 ± 2.12 to 0.83 ± 0.47, p = 0.005; LSG group, from 2.12 ± 1.73 to 0.92 ± 0.66, p = 0.001). The mean DI significantly increased from 1.14 ± 1.35 to 7.11 ± 4.93 in the RYGB group (p = 0.0001) and from 1.25 ± 1.78 to 5.60 ± 4.58 in the LSG group (p = 0.003). Compared with baseline, HOMR-IR, QUICKI, area under the curve-C-peptide release test (AUC-CRT), and AUC-OGTT were significantly changed at 6 months postoperative. Overall, 52.63% of patients in the LRYGB group versus 29.41% of patients in the LSG group achieved the triple composite endpoint. Conclusion: Both LRYGB and LSG effectively induced remission of IR in patients with T2DM and a BMI of 27.5-32.5 kg/m2.

Effect of laparoscopic Roux-en-Y gastric bypass on improvement of insulin resistance in Type 2 diabetic patients evaluated by hyperinsulinemic-euglycemic clamp. / é«˜èƒ°å²›ç´ -正葡萄糖钳夹实验评价Roux-en-Y胃旁路术对2åž‹ç³–å°¿ç— æ‚£è€ èƒ°å²›ç´ æŠµæŠ—çš„æ”¹å–„ä½œç”¨.

OBJECTIVES: With the increase of people's living standards increasing year by year, Type 2 diabetes has brought great economic and living burden to the society and patients. Bariatric surgery can improve metabolic indicators in patients with diabetes, but specific mechanisms are still under study. This study aims to evaluate the effect of Roux-en-Y gastric bypass (RYGB) on insulin resistance in patients with Type 2 diabetes by hyperinsulinemic-euglycemic clamp. METHODS: The peripheral glucose uptake (M value) of 40 patients undergoing laparoscopic Roux-en-Y gastric bypass surgery before and 6 months after the operation were analyzed hyperinsulinemic euglycemic clamp. Fasting blood glucose, glycosylated hemoglobin, triglycerides, andlow-density lipoprotein cholesterol levels as well as body mass index were also analyzed. RESULTS: M value of patients after laparoscopic Roux-en-Y gastric bypass was significantly higher than that before the operation, while indexes such as fasting blood glucose, glycosylated hemoglobin, triglycerides, and low-density lipoprotein cholesterol levels as well as body mass index were lower than those before the operation (all P<0.05). CONCLUSIONS: Laparoscopic Roux-en-Y gastric bypass surgery significantly improves insulin resistance in patients with Type 2 diabetes, decreases blood sugar and blood lipid, and can exert a positive effect on the treatment of Type 2 diabetes.

Effect of sleeve gastrectomy on gastroesophageal reflux in patients with metabolic syndrome. / è¢–çŠ¶èƒƒåˆ‡é™¤æœ¯å¯¹ä»£è°¢ç»¼åˆå¾æ‚£è€ èƒƒé£Ÿç®¡åæµç—‡çŠ¶çš„å½±å“.

OBJECTIVES: To investigate the incidence of gastroesophageal reflux disease (GERD) after sleeve gastrectomy and the effect of sleeve gastrectomy in treating the symptom of gastroesophageal reflux in patients with metabolic syndrome. METHODS: We retrospectively analyzed 60 patients with metabolic syndrome who received laparoscopy sleeve gastrectomy in the Department of Bariatric and Metabolic Surgery, Third Xiangya Hospital of Central South University from April 2018 to May 2019, and assessed the changes of symptoms before and after surgery. RESULTS: The study included 31 men and 29 women. The age of these patients was 16-46 (29.17±7.23) years, ranging from 16 to 46 years. The weight and body mass index (BMI) of the patients decreased from (116.02±31.96) kg and (39.67±8.90) kg/m2 to (98.32±25.22) kg and (34.4±7.85) kg/m2 at 1 month after the surgery, respectively. The number of patients with gastroesophageal reflux was 37(61.67%) before the surgery, and 18(30.00%) at 1 month after the surgery, respectively. The number of asymptomatic patients before the surgery while had gastroesophageal reflux symptoms within 1 month after the surgery was 4(6.67%). Among the 37 patients, 6(16.62%) had persisted or worsen symptoms with gastroesophageal reflux symptoms before the surgery, 23(62.16%) had no symptoms, and 8 patients (21.62%) showed improvement of gastroesophageal reflux 1 month after the surgery. Some scores of the GERD-Health-Related Quality of Life Scale (such as reflux after dinner) were significantly lower after the surgury than those before the surgery (P<0.05). CONCLUSIONS: The symptoms of GERD are effectively improved after surgery. Sleeve gastrectomy is a feasible, safe and effective treatment for obesity with GERD.

Erratum: The role of visceral adipose tissue on improvement in insulin sensitivity following Roux-en-Y gastric bypass: a study in Chinese diabetic patients with mild and central obesity.

[This corrects the article DOI: 10.1093/gastro/goy024.].

The role of visceral adipose tissue on improvement in insulin sensitivity following Roux-en-Y gastric bypass: a study in Chinese diabetic patients with mild and central obesity.

BACKGROUND: Most Chinese patients with type 2 diabetes mellitus (T2DM) have mild obesity and central obesity. Central obesity is combined with insulin resistance. The aim of this study was to assess the effect of abdominal adipose tissue on insulin-sensitivity improvement after Roux-en-Y gastric bypass (RYGB) in Chinese diabetic patients with mild and central obesity. METHODS: Seventeen T2DM patients with a mean body mass index of 30.3 kg/m2 were scheduled for laparoscopic RYGB. A hyperinsulinemic-euglycemic clamp and dual-energy X-ray absorptiometry were performed prior to surgery and 3 months after RYGB. The primary end points were the correlations between insulin sensitivity and abdominal adipose tissue, including visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), before and 3 months after RYGB. RESULTS: Indices of peripheral insulin sensitivity, including glucose-disposal rate (M value) and glucose infusion rate, were significantly increased after RYGB. Body-fat mass, VAT and SAT were significantly reduced after RYGB. The pre-operative M value was significantly correlated with VAT mass (r = -0.57, P = 0.02), but not correlated with SAT mass. M value changes after RYGB were highly correlated with changes in VAT mass (r = -0.59, P = 0.01), percentage of VAT mass (r = -0.66, P < 0.01), VAT area (r = -0.56, P = 0.02) and percentage of VAT area (r = -0.57, P = 0.02). CONCLUSIONS: A significant correlation was observed between increased peripheral insulin sensitivity and decreased VAT following RYGB in Chinese patients with mild and central obesity. VAT and SAT were significantly decreased with improved insulin sensitivity after RYGB. VAT mass may be considered as an indication for gastric bypass during patient selection.

Preoperative Fasting C-Peptide Predicts Type 2 Diabetes Mellitus Remission in Low-BMI Chinese Patients After Roux-en-Y Gastric Bypass.

OBJECTIVE: This study investigated the role of preoperative fasting C-peptide (FCP) levels in predicting diabetic outcomes in low-BMI Chinese patients following Roux-en-Y gastric bypass (RYGB) by comparing the metabolic outcomes of patients with FCP > 1 ng/ml versus FCP ≤ 1 ng/ml. METHODS: The study sample included 78 type 2 diabetes mellitus patients with an average BMI < 30 kg/m2 at baseline. Patients' parameters were analyzed before and after surgery, with a 2-year follow-up. A univariate logistic regression analysis and multivariate analysis of variance between the remission and improvement group were performed to determine factors that were associated with type 2 diabetes remission after RYGB. Linear correlation analyses between FCP and metabolic parameters were performed. Patients were divided into two groups: FCP > 1 ng/ml and FCP ≤ 1 ng/ml, with measured parameters compared between the groups. RESULTS: Patients' fasting plasma glucose, 2-h postprandial plasma glucose, FCP, and HbA1c improved significantly after surgery (p < 0.05). Factors associated with type 2 diabetes remission were BMI, 2hINS, and FCP at the univariate logistic regression analysis (p < 0.05). Multivariate logistic regression analysis was performed then showed the results were more related to FCP (OR = 2.39). FCP showed a significant linear correlation with fasting insulin and BMI (p < 0.05). There was a significant difference in remission rate between the FCP > 1 ng/ml and FCP ≤ 1 ng/ml groups (p = 0.01). The parameters of patients with FCP > 1 ng/ml, including BMI, plasma glucose, HbA1c, and plasma insulin, decreased markedly after surgery (p < 0.05). CONCLUSION: FCP level is a significant predictor of diabetes outcomes after RYGB in low-BMI Chinese patients. An FCP level of 1 ng/ml may be a useful threshold for predicting surgical prognosis, with FCP > 1 ng/ml predicting better clinical outcomes following RYGB.

Using the hyperinsulinemic euglycemic clamp to assess insulin sensitivity at 3 months following Roux-en-Y gastric bypass surgery in type 2 diabetes patients with BMI <35 kg/m2 in China.

BACKGROUND: The aim of this study was to describe short-time effect of Roux-en-Y gastric bypass (RYGB) on insulin sensitivity (IS) of Chinese diabetes patients with body mass index (BMI) <35 kg/m2 by hyperinsulinemic euglycemic clamp. MATERIALS AND METHODS: We studied 15 type 2 diabete mellitus (T2DM) patients with BMI <35 kg/m2, who underwent laparoscopical Roux-en-Y gastric bypass (LRYGB). Hyperinsulinemic-euglycemic clamp were performed at baseline and at 3 months after LRYGB. RESULTS: The glucose disposal rate (M value) increased significantly at 3 months after RYGB (from 3.36 ± 1.26 mg kg-1 min-1 to 6.30 ± 1.3 mg kg-1 min-1, p < 0.001). The time to reach euglycemia at the hyperinsulinemic euglycemic clamp reduced remarkably from baseline to 3 months after RYGB (from 114.40 ± 6.11 min to 97.93 ± 8.57 min, p < 0.001). There was a marked reduction in value of HOMA-IR (from 4.47 ± 2.20 mg kg-1 min-1 to 2.10 ± 0.75 mg kg-1 min-1, p < 0.001). The parameters of body fat distribution (body weight, BMI, waist circumference, waist to hip radio) changed obviously after surgery. RYGB caused a significant improvement in fasting and postprandial plasma glucose and insulin, HbAc1. Preoperative M value and the time to reach steady-state correlated with changes of M and the time to reach steady-state at 3 months after RYGB. CONCLUSION: Peripheral and hepatic IS improved remarkably at 3 months following RYGB, as an important mechanism for early improvement in T2DM patients with low BMI. And the time to reach euglycemia at the hyperinsulinemic euglycemic clamp may be an useful index of assessing insulin sensitivity. It is more reasonal to combine the time to reach euglycemia with M value for assessing IS.

Design study of dedicated brain PET with polyhedron geometry.

BACKGROUND: Despite being the conventional choice, whole body PET cameras with a 76 cm diameter ring are not the optimal means of human brain imaging. OBJECTIVE: In fact, a dedicated brain PET with a better geometrical structure has the potential to achieve a higher sensitivity, a higher signal-to-noise ratio, and a better imaging performance. METHODS: In this study, a polyhedron geometrical dedicated brain PET (a dodecahedron design) is compared to three other candidates via their geometrical efficiencies by calculating the Solid Angle Fractions (SAF); the three other candidates include a spherical cap design, a cylindrical design, and the conventional whole body PET. RESULTS: The spherical cap and the dodecahedron have an identical SAF that is 58.4% higher than that of a 30 cm diameter cylinder and 5.44 times higher than that of a 76 cm diameter cylinder. The conceptual polygon-shape detectors (including pentagon and hexagon detectors based on the PMT-light-sharing scheme instead of the conventional square-shaped block detector module) are presented for the polyhedron PET design. Monte Carlo simulations are performed in order to validate the detector decoding. CONCLUSIONS: The results show that crystals in a pentagon-shape detector can be successfully decoded by Anger Logic. The new detector designs support the polyhedron PET investigation.

[Recent technical research hot spots and development progresses in medical whole-body positron emission tomography].

Medical whole-body positron emission tomography (PET), one of the most successful molecular imaging technologies, has been widely used in the fields of cancer diagnosis, cardiovascular disease diagnosis and cranial nerve study. But, on the other hand, the sensitivity, spatial resolution and signal-noise-ratio of the commercial medical whole-body PET systems still have some shortcomings and a great room for improvement. The sensitivity, spatial resolution and signal-noise-ratio of PET system are largely affected by the performances of the scintillators and the photo detectors. The design of a PET system is usually a trade-off in cost and performance. A better image quality can be achieved by optimizing and balancing the key components which affect the system performance the most without dramatically increases in cost. With the development of the scintillator, photo-detector and high speed electronic system, the performance of medical whole-body PET system would be dramatically improved. In this paper, we report current progresses and discuss future directions of the developments of technologies in medical whole-body PET system.

Occipital pressure sores in two neonates.

The preference for a specific head shape can be influenced by people's culture, religious beliefs and race. Modern Chinese people prefer a "talented" head shape, which is rounded and has a long profile. To obtain their preferred head shape, some parents try to change their neonates' sleeping position. Due to these forced sleeping positions, positional skull deformities, such as plagiocephaly, may be present during the first few months of life. In this article, we report two neonatal cases, of Hui nationality and Dongxiang nationality, with occipital pressure sores that were caused by using hard objects as pillows with the intention of obtaining a flattened occiput. The pressure sores were deep to the occipital bone and needed surgical management. These pressure sores caused wounds that were repaired by local skin flaps, after debridement, and the use of external constraints from a dense sponge-made head frame for approximately two weeks. One case recovered with primary healing after surgical operation. The other case suffered from a disruption of the sutured wound, and a secondary operation was performed to cover the wound. These occipital pressure sores are avoidable by providing guidance to the parents in ethnic minorities' area regarding the prevention, diagnosis and management of positional skull deformity.

Observations on the curative effect of lactulose for postpartum constipation based on a large sample study.

UNLABELLED: To evaluate the efficacy and safety of lactulose in the intervention treatment of postpartum women with constipation. METHODS: The study adopted the multicenter clinical survey with a big sample which enrolled 4781 valid questionnaires from postpartum women in 18 different districts. All of them were treated with lactulose oral solution. Their constipation-related symptoms and routine examination on blood, urine and stool were monitored before and after lactulose intervention. The treatment duration lasted 2 weeks and all the patients were followed for 4 weeks. RESULT: Their stool consistency, daily defecation frequencies, defecating time and dyschezia were improved significantly after lactulose intervention, and the good therapeutic effect was remained at the off-medication session. Furthermore, abnormal rate of each index in blood, urine and stool examination showed a decreased trend. CONCLUSION: Lactulose offered good therapeutic benefit and could be developed as an effective intervention to postpartum women with constipation.

A flood map based DOI decoding method for block detector: a GATE simulation study.

Positron Emission Tomography (PET) systems using detectors with Depth of Interaction (DOI) capabilities could achieve higher spatial resolution and better image quality than those without DOI. Up till now, most DOI methods developed are not cost-efficient for a whole body PET system. In this paper, we present a DOI decoding method based on flood map for low-cost conventional block detector with four-PMT readout. Using this method, the DOI information can be directly extracted from the DOI-related crystal spot deformation in the flood map. GATE simulations are then carried out to validate the method, confirming a DOI sorting accuracy of 85.27%. Therefore, we conclude that this method has the potential to be applied in conventional detectors to achieve a reasonable DOI measurement without dramatically increasing their complexity and cost of an entire PET system.

Relationship between nm23H1 genetic instability and clinical pathological characteristics in Chinese digestive system cancer patients.

AIM: To study the relationship between nm23H1 gene genetic instability and its clinical pathological characteristics in Chinese digestive system cancer patients. METHODS: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze the microsatellite instability (MSI) and loss of heterozygosity (LOH). Immunohistochemistry was employed to detect the expression of nm23H1. RESULTS: The MSI was higher in TNM stage I + II than in stage III + IV of gastric, colonic and gallbladder carcinomas. The LOH was higher in TNM stage III + IV than in stage I + II of gastric, colonic and hepatocellular carcinomas. Lymphatic metastasis was also observed. The expression of nm23H1 protein was lower in TNM stage III + IV than in stage I + II of these tumors and in patients with lymphatic metastasis.The nm23H1 protein expression was higher in the LOH negative group than in the LOH positive group. CONCLUSION: MSI and LOH may independently control the biological behaviors of digestive system cancers. MSI could serve as an early biological marker of digestive system cancers. Enhanced expression of nm23H1 protein could efficiently inhibit cancer metastasis and improve its prognosis. LOH mostly appears in late digestive system cancer.

Lymphatic metastasis and nm23H1 genetic instability in Chinese colon cancer patients.

AIM: To investigate the pathogenic mechanism of colon cancer at the molecular level and to elucidate the relationship between intercellular adhesion molecule-1 (ICAM-1) and nm23H(1) genes and Chinese patients with colon cancer. METHODS: DNA was extracted from paraffin-embedded materials. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze MSI and LOH. Expression of ICAM-1 was detected by Envision immuno-histochemistry. Experimental results were analyzed with Leica-Qwin computer imaging techniques and SPSS software of statistics. RESULTS: ICAM-1 expression of lymphatic endothelium was negative in normal colon and positive in colon cancer respectively. The number of lymphatics positive for ICAM-1 was gradually increased with degree of cancer invasion (P<0.01). In the group with metastasis of colon cancer, the number of lymphatics positive for ICAM-1 in lymph nodes was more than that in the group with no metastasis (P<0.01). The frequency of MSI, LOH and nm23H(1) protein was 26.67%, 20.00% and 53.33% in colon cancer, respectively. In TNM staging, MSI (43.75%) and nm23H(1) protein (81.25%) in stages I+II were detected more easily than the corresponding indexes (MSI: 7.14%, P<0.05 and nm23H(1): 21.43%, P<0.01) in stages III+IV. By comparison, the frequency of LOH (35.71%) in stages III+IV was more than that of LOH (6.25%, P<0.05) in stages I+II. LOH exhibited a rising trend along with the Duke's staging. nm23H(1) protein in the group of tubular adenocarcinoma (60.00%) was higher expressed than that in the group of mucoid adenocarcinoma (20.00%) (P<0.01), and exhibited a rising trend with the differentiation degrees of tubular adenocarcinoma. nm23H(1) protein in MSI positive group was higher expressed (75%) than that in MSI negative group (45.45%, P<0.05). CONCLUSION: The expression of ICAM-1 in lymphatic vessels is beneficial to the judgement of the invasion and metastasis ability of colon cancer and the anti-tumor immunity function, and shows an important clinical significance in predicting lymphatic metastasis of colon cancer. MSI and LOH may separately control the development of sporadic colon cancer with different pathways. LOH mostly arises in the late period of sporadic colon cancer and endows a high aggressive and poor prognostic phenotype. By compassion, MSI may be an early period molecule marker for sporadic colon cancer, enhanced expression of nm23H(1) protein can effectively inhibit colon cancer metastasis and improve prognosis of sporadic colon cancer patients.