Growth, morphology and electronic properties of epitaxial graphene on vicinal Ir(332) surface.

Superlattice induced minigaps in graphene band structure due to underlying one-dimensional nanostructuration has been demonstrated. A superperiodic potential can be introduced in graphene if the substrate is periodically structured. The successful preparation of a periodically nanostructured substrate in large scale can be obtained by carefully studying the electronic structure with a spatial averaging technique such as high-energy resolution photoemission. In this work, we present two different growth methods such as temperature programmed growth (TPG) and chemical vapor deposition (CVD) studied by scanning tunnelling microscopy (STM) and low energy electron diffraction (LEED). In both methods, we show that the original steps of Ir(332) have modified with (111) terraces and step bunching after graphene growth. Graphene grows continuously over the terrace and the step bunching areas. We observe that while TPG growth does not give rise to a well-defined surface periodicity required for opening a bandgap, the CVD growth does. By combining with angle-resolved photoemission spectroscopy (ARPES) measurements, we correlate the obtained spatial periodicity to observed band gap opening in graphene.

Semiconducting Graphene from Highly Ordered Substrate Interactions.

While numerous methods have been proposed to produce semiconducting graphene, a significant band gap has never been demonstrated. The reason is that, regardless of the theoretical gap formation mechanism, subnanometer disorder prevents the required symmetry breaking necessary to make graphene semiconducting. In this work, we show for the first time that semiconducting graphene can be made by epitaxial growth. Using improved growth methods, we show by direct band measurements that a band gap greater than 0.5 eV can be produced in the first graphene layer grown on the SiC(0001) surface. This work demonstrates that order, a property that remains lacking in other graphene systems, is key to producing electronically viable semiconducting graphene.

Meat quality traits and proteome profile of woody broiler breast (pectoralis major) meat.

Woody breast meat has recently become prevalent in the broiler industry in both the United States and European Union. Recent publications have described the meat quality characteristics of woody breast meat as having hardened areas and pale ridge-like bulges at both the caudal and cranial regions of the breast. The present study investigated the meat quality (pH, color, cooking loss, and shear force) and protein quality characteristics (protein and salt-soluble protein content) in woody breast meat as compared to normal breast meat. In addition, the differences in the muscle proteome profiles of woody and normal breast meat were characterized. Results indicated that woody breast meat had a greater average pH (P < 0.0001) and cooking loss (P = 0.001) than normal breast meat, but woody breast meat did not differ in shear force (P > 0.05) in comparison to normal breast meat samples. The L*, a*, and b* values of woody breast fillets were greater than normal breast fillets (P < 0.0001 to L*; P = 0.002 to a*; P = 0.016 to b*). The woody breast meat had more fat (P < 0.0001) and moisture (P < 0.021) and less protein (P < 0.0001) and salt-soluble protein (P < 0.0001) when compared with normal breast fillets. Whole muscle proteome analysis indicated 8 proteins that were differentially expressed (P < 0.05) between normal and woody breast meat samples. The differences in muscle proteome between normal and woody breast meat indicated an increased oxidative stress in woody breast meat when compared to normal meat. In addition, the abundance of some glycolytic enzymes, which are critical to the regeneration of adenosine triphosphate (ATP) in postmortem muscles, was lower in woody breast meat than in normal breast meat. Proteomic differences provide additional information on the biochemical pathways and genetic variations that lead to woody breast meat. Further research should be conducted to elucidate the genetic and nutritional contributions to the proliferation of woody breast meat in the United States.

Proteomic approach to characterize biochemistry of meat quality defects.

Proteomics can be used to characterize quality defects including pale, soft, and exudative (PSE) meat (pork and poultry), woody broiler breast meat, reddish catfish fillets, meat toughness, and beef myoglobin oxidation. PSE broiler meat was characterized by 15 proteins that differed in abundance in comparison to normal broiler breast meat, and eight proteins were differentially expressed in woody breast meat in comparison to normal breast meat. Hemoglobin was the only protein that was differentially expressed between red and normal catfish fillets. However, inducing low oxygen and/or heat stress conditions to catfish fillets did not lead to the production of red fillets. Proteomic data provided information pertaining to the protein differences that exist in meat quality defects. However, these data need to be evaluated in conjunction with information pertaining to genetics, nutrition, environment of the live animal, muscle to meat conversion, meat quality analyses and sensory attributes to understand causality, protein biomarkers, and ultimately how to prevent quality defects.

Early detection of HIV-1 in infants by PCR.

Infants of HIV-infected mothers are at great risk of becoming infected with HIV during childbirth. Many infants acquire HIV during labor and delivery. Others can acquire HIV through the mixing of fetal and maternal blood as the placenta separates. The duration of membrane rupture, acute chorioamnionitis and invasive delivery techniques that increase the baby's contact with the mother's blood have been associated with higher risks of MTCT during labor and delivery. HIV is present in breast milk and risk of its transmission during breastfeeding depends on several factors, including: infant age, pattern of breastfeeding, breastfeeding duration, breast health, maternal viral load and maternal immune status. Infants born to HIV infected mothers carry their mother's antibodies in their blood into the second year of life, even if the infants themselves are not infected. For this reason, standard HIV antibody tests cannot reliably confirm HIV infection in infants until after the maternal antibodies have disappeared. Tests that can diagnose pediatric HIV infection accurately during the first year of life include HIV-PCR, CD4/CD8 counts, P24 antigen tests, and viral cultures. PCR offers an effective tool to reliably diagnose HIV in a pediatric age group. Nineteen infants born by normal delivery to HIV-1 seropositive mothers were studied by PCR for the HIV1 env gene. Thirteen babies (68.5%) were negative whereas 6 babies were found to be positive (31.5%). Although PCR is one of the most useful tests for this clinical situation, it is not definitive. Therefore, PCR should be interpreted with caution and repeated at regular defined intervals, preferably lasting until the HIV antibody status of the infant is resolved.

The baboon (Papio anubis) extracranial carotid artery: an anatomical guide for endovascular experimentation.

BACKGROUND: As novel endovascular strategies are developed for treating neurological disease, there is an increasing need to evaluate these techniques in relevant preclinical models. The use of non-human primates is especially critical given their structural and physiological homology with humans. In order to conduct primate endovascular studies, a comprehensive understanding of the carotid anatomy is necessary. We therefore performed a detailed examination of the vessel lengths, lumen diameters and angles of origin of the baboon extracranial carotid system. METHODS: We characterized the extracranial carotid system often male baboons (Papio anubis, range 15.1-28.4 kg) by early post-mortem dissection. Photographic documentation of vessel lengths, lumen diameters, and angles of origin were measured for each segment of the carotid bilaterally. RESULTS: The common carotid arteries averaged 94.7 +/- 1.7 mm (left) and 87.1 +/- 1.6 mm (right) in length. The average minimal common carotid lumen diameters were 3.0 +/- 0.3 mm (left) and 2.9 +/- 0.2 mm (right). Each animal had a common brachiocephalic artery arising from the aorta which bifurcated into the left common carotid artery and right braciocephalic artery after 21.5 +/- 1.6 mm. The vascular anatomy was found to be consistent among animals despite a wide range of animal weights. CONCLUSIONS: The consistency in the Papio anubis extracranial carotid system may promote the use of this species in the preclinical investigation of neuro-interventional therapies.

Sedation analgesia in pediatric intensive care.

Provision of optimum comfort control to a critically ill child, in Pediatric Intensive Care Unit (PICU) requires a great degree of skill and planning and should be a prime concern for all practising paediatricians. Failure to provide adequate sedation and analgesia to control the stress response has been seen to be associated with increased complications and mortality. Sedation/analgesia in PICU is required both for, short term procedure and as an adjunct to pediatric intensive care. One has to identify the requirement whether sedation, analgesia or both. The ideal approach should be a sedative/hypnotic for sedation, an anxiolytic for anxiety, and an analgesic for pain. Threfore, it is essential, to provide the right drug for the problem at the right time in the right dosage. The drugs commonly used for sedation analgesia in PICU and their side effects have been described here.

Intrapelvic obturator neurectomy in cerebral palsy.

Results of 202 obturator neurectomies including 190 intrapelvic and 8 extrapelvic obturator neurectomies in 100 patients were evaluated. Obturator neurectomy, intrapelvic in particular, yielded gratifying results in properly selected patients. It controlled adductor spasticity, scissoring, improved perineal care and helped the patients in sitting and early ambulation. Pre- and post-operative intensive physiotherapy was necessary to get maximum benefit of the surgery. Poor motor status, low IQ, athetosis and inadequate post-operative care had adverse effect on final outcome.

Neonatal lupus mimicking extra hepatic biliary atresia.

Neonatal Lupus Erythematosus (NLE) is an uncommon condition manifesting with congenital complete heart block and occasionally other manifestations like hepatitis. Neonatal Lupus with severe cholestasis with positive anti SS-A/Ro and anti SS-B/La antinuclear antibodies in the mother and child is being reported.

Polymerase chain reaction in the diagnosis of tuberculosis.

OBJECTIVES: To evaluate efficacy of polymerase chain reaction (PCR), using the insertion sequence IS6110 as target for DNA, to detect Mycobacterium tuberculosis in body fluids of children with suspected tuberculosis (TB). SETTING: Hospitalized patients. METHODS: A comparison of PCR on body fluids, Acid Fast Bacilli staining (AFB), mycobacterial culture and clinical features, with special emphasis on central nervous system (CNS) TB was done over 18 month period. A total of 80 children were evaluated, 41 with probable TB disease and 39 controls. Cases were defined by specific clinical criteria. Controls included patients free of clinical TB. PCR was done on the clinical specimens and compared with clinical findings, radiological features, Mantoux (Mx) testing, AFB staining and culture on Lowenstein-Jensen (LJ) medium. RESULTS: Sensitivity of PCR in CSF samples was 100%, in gastric aspirate samples was 20% and in pleural fluid samples was 100%. CONCLUSION: PCR technique may become a valuable diagnostic tool for the diagnosis of tuberculosis in children especially in CNS TB.

2013 Early Career Achievement Award--Proteomics of muscle- and species-specificity in meat color stability.

Meat color is the most important quality trait influencing consumer purchase decisions. The interinfluential interactions between myoglobin and biomolecules govern color stability in meat. The advances in proteomics, such as high throughput analytical tools in mass spectrometry, 2-dimensional electrophoresis, and bioinformatics, offer themselves as robust techniques to characterize the proteome basis of muscle- and species-specific meat color phenomena. Differential abundance of chaperones and antioxidant proteins contributes to muscle-specific color stability in beef; the greater abundance of chaperones and antioxidant proteins in color-stable Longissimus lumborum than in color-labile Psoas major protects myoglobin and contributes to superior color stability of beef Longissimus steaks. Lipid oxidation-induced myoglobin oxidation is more critical to beef color than pork color due to the inherent differences in myoglobin chemistry; the number of nucleophilic histidine residues adducted by reactive aldehydes is greater in beef myoglobin than in pork myoglobin. Preferential adduction of secondary products of lipid oxidation to beef myoglobin accelerates metmyoglobin formation at a greater degree than in its pork counterpart. Mass spectrometric investigations revealed that although cherry-red carboxymyoglobin is more stable than oxymyoglobin, both redox forms undergo lipid oxidation-induced oxidation in model systems. The accuracy of mass spectrometry to detect the molecular mass of proteins has been applied to differentiate myoglobins from closely related meat animals, such as goats and sheep or emu and ostrich. In addition, this approach indicated that turkey myoglobin is 350 Da greater in molecular mass than beef myoglobin, and the unique biochemistry of turkey myoglobin could be responsible for its greater thermostability in model systems as well as the pink color defect observed in fully cooked uncured turkey products.

Temperature- and pH-dependent effect of lactate on in vitro redox stability of red meat myoglobins.

Our objective was to evaluate the influence of lactate on in vitro redox stability and thermostability of beef, horse, pork, and sheep myoglobins. Lactate (200 mM) had no effect (P>0.05) on redox stability at physiological (pH7.4, 37°C) and meat (pH 5.6, 4°C) conditions. However, lactate increased (P<0.05) metmyoglobin formation at a condition simulating stressed live skeletal muscle (pH 6.5, 37°C). The redox stability of myoglobins at stressed live skeletal muscle and meat conditions was species-specific (P<0.05). Myoglobin thermostability at 71°C was lower (P<0.05) in the presence of lactate compared with controls and was influenced (P<0.05) by species. The results of the present study indicate that the effects of lactate on myoglobin are temperature and pH dependent. The observed lack of influence of lactate on myoglobin redox stability at meat condition suggests that the color stability of lactate-enhanced fresh meat is not due to direct interactions between the ingredient and the heme protein.

Lipid oxidation-induced oxidation in emu and ostrich myoglobins.

Emu and ostrich are ratites gaining increasing popularity as sources of low-fat meats. Secondary products of lipid oxidation, such as 4-hydroxy-2-nonenal (HNE), compromise myoglobin redox stability in a species-specific manner. However, the molecular basis of lipid oxidation-induced oxidation in ratite myoglobins has not been investigated. Therefore, our objective was to characterize lipid oxidation-induced oxidation in ratite myoglobins, in comparison with beef myoglobin. At physiological condition (pH7.4, 37 °C) HNE accelerated (P<0.05) oxidation of emu, ostrich, and beef oxymyoglobins. Autoxidation and HNE-induced oxidation were greater (P<0.05) in ostrich oxymyoglobin than in emu and beef oxymyoglobins. Mass spectrometric analyses revealed that HNE formed mono-adduct with both emu and ostrich myoglobins after 6h of incubation. Tandem mass spectrometry demonstrated that HNE adducted histidine 36 in ostrich myoglobin, whereas histidines 34 and 36 were adducted in emu myoglobin. The results indicate that primary structure of ratite myoglobins influences their redox stability in the presence of prooxidants.

Reconstructive surgery of claw hand in leprosy.

32 hands in 31 known cases of leprosy were operated using the Paul-Brand technique for the intrinsic minus deformity. 29 hands revealed good results whereas remaining 3 also had definite improvement in their function and cosmesis. Bunnel's opponens plasty was performed in 7 cases to restore back the power of opponens in the thumb. Meticulous pre and postoperative management proved to be very necessary.