Effect of postpartum maternal or neonatal vitamin A supplementation on infant mortality among infants born to HIV-negative mothers in Zimbabwe

BACKGROUND: Young infants are at risk of vitamin A deficiency. Supplementation of breastfeeding mothers improves the vitamin A status of their infants, but there are no data regarding its effect on infant mortality, and data on the effect of directly supplementing infants during the first few weeks of life are conflicting. OBJECTIVE: The objective was to measure the effect on infant mortality of supplementing neonates and their HIV-negative mothers with single, large doses of vitamin A during the immediate postpartum period. DESIGN: A randomized, placebo-controlled, 2-by-2 factorial design trial was conducted in 14,110 mothers and their infants; 9208 of the mothers were HIV-negative at delivery, remained such during the postpartum year, and were retained in the current analysis. The infants were randomly assigned within 96 h of delivery to 1 of 4 treatment groups: mothers and infants received vitamin A (Aa), mothers received vitamin A and infants received placebo (Ap), mothers received placebo and infants received vitamin A (Pa), and both mothers and infants received placebo (Pp). The vitamin A dose in the mothers was 400,000 IU and in the infants was 50,000 IU. The mother-infant pairs were followed to 12 mo. RESULTS: Hazard ratios (95% CI) for 12 mo mortality among infants in the maternal-supplemented and infant-supplemented groups were 1.17 (0.87, 1.58) and 1.08 (0.80, 1.46), respectively. Hazard ratios (95% CI) for the Aa, Ap, and Pa groups compared with the Pp group were 1.28 (0.83, 1.98), 1.27 (0.82, 1.97), and 1.18 (0.76, 1.83), respectively. These data indicate no overall effect. Serum retinol concentrations among a subsample of women were similar to reference norms. CONCLUSION: Postpartum maternal or neonatal vitamin A supplementation may not reduce infant mortality in infants of HIV-negative women with an apparently adequate vitamin A status.     

A humanised tissue‐engineered bone model allows species‐specific breast cancer‐related bone metastasis in vivo

Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.     

自体骨髓干细胞移植治疗失代偿期肝硬化

选择36例失代偿期肝硬化患者,年龄37～59岁,患者在无菌条件下,从髂后上棘抽取骨髓100～200mL,在体外分离纯化骨髓干细胞后,局部麻醉下经股动脉插管经肝动脉将分离的骨髓干细胞移植于肝脏。自移植后12周,25例(69.4%)患者谷丙转氨酶逐渐降低,由平均(2788.56±357.90)nkat/L降至(1077.05±440.25)nkat/L;22例(61.1%)患者总胆红素逐渐下降,由平均(151.47±25.77)μmol/L降至(69.93±18.86)μmol/L;27例(75%)患者白蛋白逐渐升高,由平均(25.17±11.79)g/L升至(30.87±12.17)g/L。在干细胞移植后凝血酶原活动度逐渐上升,由术前平均(25.89±12.67)%上升至术后12周的(50.39±19.38)%,患者凝血机制明显改善。移植后大多数患者身体状况有明显的改善;移植后12周腹水减轻的19例(52.7%),食欲改善的28例(77.7%),体力好转20例(58.3%),腹胀减轻17例(47.2%),36例干细胞移植患者未出现严重并发症。     

犬内皮与平滑肌细胞的短期静态联合培养

目的:为获得组织工程化自体血管,观察体外静态培养条件下犬内皮细胞与平滑肌细胞联合培养组织学及形态学的特征。方法:实验于2004-07/2005-06在首都医科大学宣武医院外科院级实验室完成。①实验材料:雄性杂种犬,3个月龄,体质量8～12kg。②实验方法:贴块法及酶解法对犬内皮细胞及平滑肌细胞进行原代分离培养及扩增,将第Ⅱ代平滑肌细胞以1×109L-1的密度种植于胶原膜上培养13d,再将第Ⅱ代内皮细胞接种于生长平滑肌细胞的胶原膜上2d。③实验评估:行苏木精-伊红染色同时扫描电镜和透射电镜观察平滑肌细胞和内皮细胞在胶原载体上联合培养后的形态。结果:苏木精-伊红染色见平滑肌细胞较均匀的分布于支架材料表面及内部;扫描电镜下,平滑肌细胞可以在胶原载体材料上生长,增殖明显并在短期内形成多层细胞。内皮细胞与平滑肌细胞联合培养2d就可在平滑肌细胞层表面获得连续的单层内皮细胞层。结论:在短期静态培养条件下犬的血管平滑肌细胞和内皮细胞可以在胶原载体材料上形成具有两层细胞结构的组织工程化动脉血管组织片。     

Pushing the limits of liver surgery for colorectal liver metastases:Current state and future directions

Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery.Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.     

Impregnation of bone chips with antibiotics and storage of antibiotics at different temperatures: an <Emphasis Type="Italic">in vitro</Emphasis> study

Background  

Allograft bone used in joint replacement surgery can additionally serve as a carrier for antibiotics and serve as a prophylaxis against infections. However, in vitro dose-response curves for bone chips impregnated with different kinds of antibiotics are not available. In addition, while it would be desirable to add the antibiotics to allograft bone chips before these are stored in a bone bank, the effects of different storage temperatures on antibiotics are unknown.     

First trimester urinary placental growth factor and development of pre-eclampsia

Objective  To compare urinary placental growth factor (PlGF) concentration at 11⁺⁰ to 13⁺⁶ weeks of gestation in women who subsequently develop pre-eclampsia with normotensive controls.
Design  Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting  Routine antenatal visit in a teaching hospital.
Population  Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods  Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures  Development of pre-eclampsia.
Results  In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions  The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy.     

Acute acalculous cholecystitis: sensitivity in detection using technetium-99m iminodiacetic acid cholescintigraphy

Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease.