Remote ischemic preconditioning with – but not without – metabolic support protects the neonatal porcine heart against ischemia-reperfusion injury

Background

While remote ischemic preconditioning (rIPC) protects the mature heart against ischemia-reperfusion (IR) injury, the effect on the neonatal heart is not known. The neonatal heart relies almost solely on carbohydrate metabolism, which is modified by rIPC in the mature heart. We hypothesized that rIPC combined with metabolic support with glucose-insulin (GI) infusion improves cardiac function and reduces infarct size after IR injury in neonatal piglets in-vivo.

Methods and results

32 newborn piglets were randomized into 4 groups: control, GI, GI + rIPC and rIPC. GI and GI + rIPC groups received GI infusion continuously from 40 min prior to ischemia. rIPC and GI + rIPC groups underwent four cycles of 5 min limb ischemia. Myocardial IR injury was induced by 40 min occlusion of the left anterior descending artery followed by 2 h reperfusion. Myocardial lactate concentrations were assessed in microdialysis samples analyzed by mass spectrometry. Infarct size was measured using triphenyltetrazolium chloride staining. Systolic recovery (dP/dt_max as % of baseline) after 2 h reperfusion was 68.5 ± 13.8% in control, 53.7 ± 11.2% in rIPC (p < 0.05), and improved in GI (83.6 ± 18.8%, p < 0.05) and GI + rIPC (87.0 ± 15.7%, p < 0.01).

Conclusion

rIPC + GI protects the neonatal porcine heart against IR injury in-vivo. rIPC alone has detrimental metabolic and functional effects that are abrogated by simultaneous GI infusion.     

An investigation into the distribution of different collagen types within adult and juvenile porcine pancreata

One of the difficulties of porcine islet isolation is their fragility during collagenase digestion. The object of this study was to determine the distribution of 4 different collagen types within adult and juvenile porcine pancreata. Five different areas from each pancreas were analysed by light microscopy. The distribution of collagen types I, IV, V and VI were measured within the interlobar, intralobular (acinar), peri-insular and intra-islet regions. Their was an abundance of collagen type VI compared to I, IV and V in both the interlobar and intralobular septa in both juveniles (P<0.001) and adults (P<0.001). The peri-insular collagen content also showed diversity. This was mainly attributable to the distribution of collagen type I (weak) and type VI (intense) in both adults and juveniles. In general, the peri-insular capsule was fragmentary and contained less than 50% of the total islet circumference. The latter finding taken together with the distributions of different collagen types can partly explain some of the variability of porcine islet isolation.     

Functionalization and Linking Chemistry of Poly(styryl)lithium with 1,3‐Butadiene Diepoxide

Summary: The reaction of excess poly(styryl)lithium ( = 1 400 g · mol^?1) with 1,3‐butene diepoxide proceeds efficiently to produce a coupled product with two in‐chain hydroxyl groups. The pure coupled, functionalization product was isolated in quantitative yield by silica gel column chromatography. This product was characterized by ¹H and ¹³C NMR spectroscopic analyses, as well as MALDI‐TOF mass spectrometry. The DEPT ¹³C NMR spectrum showed that a disecondary 1,2‐diol unit was present, consistent with attack of PSLi on the least‐substituted, methylene carbons of 1,3‐butadiene diepoxide. The MALDI‐TOF mass spectrum of the purified product exhibited only one distribution with monoisotopic peaks corresponding to the coupled, dihydroxy‐functionalized polystyrene.

MALDI‐TOF mass spectrum of the purified, in‐chain, hydroxyl‐functionalized polystyrene and the reaction of PSLi with 1,3‐butadiene diepoxide.     

Effect of nutrition counselling with a digital job aid on child dietary diversity: Analysis of secondary outcomes from a cluster randomised controlled trial in rural Bangladesh

Adequate dietary diversity among infants is often suboptimal in developing countries. We assessed the impact of nutrition counselling using a digital job aid on dietary diversity of children aged 6–23 months using data from a cluster randomised controlled trial in Bangladesh. The trial had five arms, each with 25 clusters. The four intervention arms provided counselling using a digital job aid and different prenatal and post-natal combinations of lipid-based supplements and the comparison arm with usual practice. We enrolled 1500 pregnant women and followed them until the children reached their second birthday. We developed a tablet-based system for intervention delivery, data collection and project supervision. We combined the four intervention arms (n = 855), in which community health workers (CHWs) provided age-appropriate complementary feeding counselling, to compare against the comparison arm (n = 403). We calculated the outcome indicators from the children's 24-h dietary recalls. Overall, the intervention increased the mean dietary diversity score by 0.09 (95% confidence interval [CI]: 0.2–0.16) and odds of minimum dietary diversity by 18% (95% CI: 0.99–1.40). However, there was a significant interaction on the effect of the intervention on dietary diversity by age. The mean dietary diversity score was 0.24 (95% CI: 0.11–0.37) higher in the intervention than in the comparison arm at 9 months and 0.14 (95% CI: 0.01–27) at 12 months of age. The intervention effect was non-significant at an older age. Overall, consumption of flesh food was 1.32 times higher in the intervention arm (odds ratio [OR] 1.32, 95% CI: 1.11–1.57) in 6–23 months of age. The intervention significantly improved child dietary diversity score in households with mild and moderate food insecurity by 0.27 (95% CI: 0.06–0.49) and 0.16 (0.05–27), respectively, but not with food-secure and severely food-insecure households. Although the study did not evaluate the impact of digital job aid alone, the findings indicate the utility of nutrition counselling by CHWs using a digital job aid to improve child feeding practices in broader programmes.     

An epidemiological study of febrile seizures with special reference to family history and HLA linkage.

One hundred and forty four cases of febrile seizures, 95 simple (typical) and 49 complex (atypical); were studied and compared for clinical and epidemiological data and family history of febrile and afebrile seizures. Major results were: maximum age of onset below three years (75%) in both simple and complex groups, male preponderance, respiratory infection as the commonest etiology (69.4%) and maximum seizure onset within 24 hours of fever (73%). The familial prevalence of all seizures was 29.1%, 23.2% in the simple and 40.8% in the complex group (p < 0.01). The familial prevalence of febrile seizures was 20%; similar in both groups. The familial prevalence of afebrile seizures was 13.9%; 6.3% in simple and 28.6% in complex group (p < 0.01). The commonest relative was a sibling (13.2%). The prevalence in parents was 4%. Families with two additional members with history of seizures revealed complex seizure patterns in two-thirds of index cases. There was no correlation between family history of seizures and age at onset or sex. No clear inheritance pattern emerged and polygenic inheritance is likely. One third of eighteen families had siblings with identical segregation of parental HLA-A and B haplotypes. Five families showed the presence of HLA All. This small though adequate sample size did not reveal an HLA marker for febrile seizures.     

The risks of total pancreatectomy and splenic islet autotransplantation

The intraportal site is the most common site for islet transplantation. Many other sites have been tried experimentally, including the spleen, which has successfully lead to insulin independence in a number of animal models. Nevertheless, there are no detailed reports of total pancreatectomy and splenic islet autotransplantation in humans. Five patients underwent total pancreatectomy and splenic islet autotransplantation for chronic pancreatitis. Four patients had a pylorus-preserving total pancreatectomy and one patient a duodenal-preserving pancreatectomy. In three cases islets were embolized into both the portal vein and spleen. Two patients received splenic islet transplants alone. Islets were transplanted by retrograde venous infusion via the short gastric veins (n = 3), splenic vein stump (n = 1), and the left gastroepiploic vein (n = 1). The total volumes of transplanted pancreatic digest in those receiving combined intraportal and splenic autografts (n = 3) were 15.8, 13.0, and 13.5 ml. The volumes in those receiving a splenic-alone autograft (n = 2) were 12.0 and 5 ml. The mean rise in portal pressure was 18 cm of water. Complications related to the splenic autograft included a wedge splenic infarct, an emergency splenectomy, and a portal vein thrombosis in one patient having a combined intraportal and splenic autograft. Two patients developed insulin independence. two patients were still insulin independent at 1-year follow-up, and all had normal HbA1c levels (mean 5.6, range 5.2-6.3). Splenic islet autotransplantation, after total pancreatectomy, does lead to insulin independence. However, in our experience the combined procedure has a high morbidity because of splenic infarction and venous thrombosis.     

Organising unrestricted open access gastroscopy in South Tees.

Increasing demand for upper gastrointestinal endoscopy has forced many clinicians to reconsider the policy of seeing all patients in a specialist clinic before gastroscopy. The following are considered essential in setting up an open access gastroscopy service. (1) Assessment of the need by examination of waiting times for the outpatient clinic and the proportion of patients requiring upper gastrointestinal endoscopy, and consultation with colleagues in general practice. During the first 2 years of the service the average waiting time for a medical gastrointestinal outpatient appointment has fallen from over 120 days to 37 days in this area. (2) An adequately staffed and equipped gastrointestinal unit with well motivated nurses (the workload will increase) and sufficient clinical support to allocate patients to the next available gastroscopy list is vital. A safe mechanism for relaying information back to the GP (including histology reports) is essential otherwise medicolegal problems could arise. Open access gastroscopy now accounts for 29% of the total endoscopy workload in South Tees. (3) Close cooperation between medical and surgical gastroenterologists must be achieved to ensure a uniform approach to the provision of this service and equal distribution of the endoscopy workload. This will require close examination of the potential numbers and may necessitate appointment of a clinical assistant or additional consultant. Clinical assistants perform just over 50% of the open access gastroscopies in South Tees and the waiting time has been kept short (average 17 days). (4) A comprehensive request form with guidelines for GPs and a specific box identifying whether the GP requires a report and brief advice only or follow up at the discretion of the endoscopist (often a clinical assistant) is required. (5) Management must be involved in identifying adequate resources. (6) Methods of monitoring requests and outcome measures to ensure effective audit must be established.