International purchasing offices in China: roles and resource/capability requirements

Purpose

– The purpose of this paper is to address global sourcing organisational design through the following research questions: how do the roles performed by International Purchasing Offices (IPOs) change over time?; what are the resources/capabilities required by an IPO for an effective performance and how do they change over time?; and what are the contingent factors affecting such changes?

Design/methodology/approach

– The authors employed an exploratory multiple case study approach and analysed 14 Western IPOs located in China for a period between 2007 and 2012. The data were primarily collected through 34 direct, semi-structured interviews of IPO heads and sourcing managers or senior buyers.

Findings

– The authors identify and discuss the importance of ten roles played by IPOs and 12 required resources/capabilities. Furthermore, considering the changes that occurred to these IPOs over a five-year period (2007-2012), the authors observe three distinct evolutionary behaviours (i.e. “overall development”, “selective development”, and “stable configuration”) and highlight three contingent factors that jointly affect these behaviours (i.e. the architectural and technological complexity of the sourced items, annual volume sourced abroad, and experience in the foreign context).

Originality/value

– This paper contributes to the resource-based view of the firm in a global sourcing context by highlighting the resources/capabilities required by IPOs and discussing their characteristics. Furthermore, it proposes a typology of IPO micro-organisational evolutionary behaviours. Finally, it applies contingency theory and identifies three factors that might affect the evolutionary behaviours.

Subclinical hypothyroidism and the associations with macrovascular complications and chronic kidney disease in patients with Type 2 diabetes

AIMS

The prevalence of subclinical hypothyroidism (SCH) is high among patients with diabetes, although the relationship between SCH and diabetic vascular complications is unknown. This study aimed to determine the relationship between SCH and vascular complications in patients with Type 2 diabetes.

METHODS

In this cross sectional study, 991 patients with Type 2 diabetes were screened for thyroid function at their admission to the Second Affiliated Hospital of Chongqing Medical University. We compared the prevalence of coronary heart disease (CHD), ischaemic stroke and chronic kidney disease (CKD) with the prevalence of euthyroidism and SCH.

RESULTS

Among the 991 patients, 126 (12.7%) patients had SCH. The prevalence of CHD was significantly higher in the SCH group than in the euthyroid group (22.2% and 15.0%, respectively; P = 0.039). In the logistic regression analyses, SCH was associated with CHD [odds ratio (OR): 1.993; 95% confidence interval (CI): 1.135-3.497; P = 0.016]. This association was stronger in patients aged ≥ 65 years than in younger patients [2.474 (1.173-5.220); P = 0.017]. No significant association was found between SCH and ischaemic stroke. Patients with severe SCH had a high risk of CKD [1.842 (1.120-3.029); P = 0.016].

CONCLUSIONS

This study provides evidence that SCH in patients with Type 2 diabetes is associated with a high prevalence of CHD (and CKD in severe SCH), although not with ischaemic stroke.

Treatment of Moyamoya disease by multipoint skull drilling for indirect revascularization combined with mobilization of autologous bone marrow stem cells

This study discusses the clinical efficacy of multipoint skull drilling for indirect revascularization combined with mobilization of autologous bone marrow stem cells and use of simvastatin in the treatment of moyamoya disease. Seventy-eight patients [control group (group A), 39 patients; experimental group (group B), 39 patients] with moyamoya disease were selected. Group A underwent indirect revascularization, and group B, in addition to indirect revascularization, received alternate subcutaneous injections from day 7 post-surgery. The number and differentiation of the mobilized bone marrow stem cells were detected by the proportion of hematopoietic progenitor cell (HPCs) in mononuclear cells (MNCs) in the peripheral blood. There was no statistical difference in the BI (80.2 ± 13.7) and NIHSS (6.7 ± 2.3) scores between the groups before treatment (P > 0.05). The CSS score of group B was 13.5 ± 0.6 and there was a statistical significance compared to group A (18.2 ± 0.8) (P < 0.05). There was no statistical difference in the proportion of CD34+ CDl33+ cells in MNCs in peripheral blood before surgery between the two groups (P > 0.05) and the proportions of CD34+ CDl33+ cells in MNCs in peripheral blood in groups A and B at 30 days after surgery were significantly higher than those before surgery (P < 0.05). Treating moyamoya disease by multipoint skull drilling for indirect revascularization combined with mobilization of autologous bone marrow stem cells and simvastatin is a safe and effective method as it can promote recovery of neurological functions and improve patients' daily living abilities and quality of life.

Interaction analysis of IL-12A and IL-12B polymorphisms with the risk of colorectal cancer

IL-12 is an antitumor cytokine with functions of inhibiting tumor growth, invasion, and metastasis, indicating that IL-12 is a promising candidate for cancer treatment. The aim of this study was to investigate the association of IL-12A rs568408, IL-12A rs2243115, and IL-12B rs3212227 with the susceptibility to colorectal cancer (CRC). Two hundred and fifty-seven histopathologically confirmed CRC patients and 236 age- and gender-matched controls were enrolled. The three polymorphisms were genotyped using a polymerase chain reaction-restriction fragment length polymorphism assay. We found that the IL-12A rs568408 AG/AA genotypes were associated with an increased risk of CRC with an adjusted odds ratio (OR) of 1.66 (95 % confidence interval (CI), 1.11-2.48). Stratified analyses showed that patients carrying the IL-12B rs3212227AC/CC genotypes had a 1.97-fold increased risk of tumor metastasis (OR = 1.97; 95 % CI, 1.04-3.70). Gene-gene interaction analysis showed that subjects carrying the IL-12A rs568408AG/AA and IL-12B rs3212227AA genotypes had a 2.40-fold increased risk of CRC (OR = 2.40; 95 % CI, 1.14-5.07) and individuals carrying the IL-12A rs568408AG/AA and IL-12B rs3212227AC/CC genotypes had a 1.93-fold increased risk of CRC (OR = 1.93; 95 % CI, 1.10-3.41). These findings indicate that IL-12A rs568408 and IL-12B rs3212227 may be related to the development of CRC.

Biomechanical analysis and clinical effects of bridge combined fixation system for femoral fractures

This work aimed to compare the stress distribution and mechanical properties of our bridge combined fixation system and commonly used metal locking plate screw system by finite element analysis and by using the Zwick/Z100 testing machine. In addition, we also investigated the clinical outcome of our bridge combined fixation system for femoral fractures in 59 patients from June 2005 to January 2013. As a result, the stress distribution in the bone plate and screws of metal locking plate screw system during walking and climbing stairs was significantly lower than that of metal locking plate screw system. No significant difference in the displacement was observed between two systems. The equivalent bending stiffness of bridge combined fixation system was significantly lower than that of metal locking plate screw system. There were no significant differences in the bending strength, yield load, and maximum force between two systems. All the cases were followed up for 12-24 months (average 18 months). The X-ray showed bone callus was formed in most patients after 3 months, and the fracture line was faint and disappeared at 6-9 months postoperatively. No serious complications, such as implant breakage and wound infection, occurred postoperatively. According to self-developed standard for bone healing, clinical outcomes were rated as excellent or good in 55 out of 59 patients (success rate: 93.2%). Therefore, our findings suggest that our bridge combined fixation system may be a promising approach for treatment of long-bone fractures.

Towards effective and safe thrombolysis and thromboprophylaxis: preclinical testing of a novel antibody-targeted recombinant plasminogen activator directed against activated platelets

RATIONALE

Fibrinolysis is a valuable alternative for the treatment of myocardial infarction when percutaneous coronary intervention is not available in a timely fashion. For acute ischemic stroke, fibrinolysis is the only treatment option with a very narrow therapeutic window. Clinically approved thrombolytics have significant drawbacks, including bleeding complications. Thus their use is highly restricted, leaving many patients untreated.

OBJECTIVE

We developed a novel targeted fibrinolytic drug that is directed against activated platelets.

METHODS AND RESULTS

We fused single-chain urokinase plasminogen activator (scuPA) to a small recombinant antibody (scFvSCE5), which targets the activated form of the platelet-integrin glycoprotein IIb/IIIa. Antibody binding and scuPA activity of this recombinant fusion protein were on par with the parent molecules. Prophylactic in vivo administration of scFvSCE5-scuPA (75 U/g body weight) prevented carotid artery occlusion after ferric chloride injury in a plasminogen-dependent process compared with saline (P<0.001), and blood flow recovery was similar to high-dose nontargeted urokinase (500 U/g body weight). Tail bleeding time was significantly prolonged with this high dose of nontargeted urokinase, but not with equally effective targeted scFvSCE5-scuPA at 75 U/g body weight. Real-time in vivo molecular ultrasound imaging demonstrates significant therapeutic reduction of thrombus size after administration of 75 U/g body weight scFvSCE5-scuPA as compared with the same dose of a mutated, nontargeting scFv-scuPA or vehicle. The ability of scFvSCE5-scuPA to lyse thrombi was lost in plasminogen-deficient mice, but could be restored by intravenous injection of plasminogen.

CONCLUSIONS

Targeting of scuPA to activated glycoprotein IIb/IIIa allows effective thrombolysis and the potential novel use as a fibrinolytic agent for thromboprophylaxis without bleeding complications.

Novel single-chain antibody-targeted microbubbles for molecular ultrasound imaging of thrombosis: validation of a unique noninvasive method for rapid and sensitive detection of thrombi and monitoring of success or failure of thrombolysis in mice

BACKGROUND

Molecular imaging is a fast emerging technology allowing noninvasive detection of vascular pathologies. However, imaging modalities offering high resolution currently do not allow real-time imaging. We hypothesized that contrast-enhanced ultrasound with microbubbles (MBs) selectively targeted to activated platelets would offer high-resolution, real-time molecular imaging of evolving and dissolving arterial thrombi.

METHODS AND RESULTS

Lipid-shell based gas-filled MBs were conjugated to either a single-chain antibody specific for activated glycoprotein IIb/IIIa via binding to a Ligand-Induced Binding Site (LIBS-MBs) or a nonspecific single-chain antibody (control MBs). Successful conjugation was assessed in flow cytometry and immunofluorescence double staining. LIBS-MBs but not control MBs strongly adhered to both immobilized activated platelets and microthrombi under flow. Thrombi induced in carotid arteries of C57Bl6 mice in vivo by ferric chloride injury were then assessed with ultrasound before and 20 minutes after MB injection through the use of gray-scale area intensity measurement. Gray-scale units converted to decibels demonstrated a significant increase after LIBS-MB but not after control MB injection (9.55±1.7 versus 1.46±1.3 dB; P<0.01). Furthermore, after thrombolysis with urokinase, LIBS-MB ultrasound imaging allows monitoring of the reduction of thrombus size (P<0.001).

CONCLUSION

We demonstrate that glycoprotein IIb/IIIa-targeted MBs specifically bind to activated platelets in vitro and allow real-time molecular imaging of acute arterial thrombosis and monitoring of the success or failure of pharmacological thrombolysis in vivo.

Influence of single-walled carbon nanotubes on microbial availability of phenanthrene in sediment

Increasing production and use of single-walled carbon nanotubes (SWCNT) will inevitably lead to release of these nanoparticles to aquatic ecosystems. Similar to black carbon (BC) particles, SWCNT have a high affinity for hydrophobic organic contaminants (HOCs) and therefore the presence of SWCNT in sediment may lead to altered bioavailability of HOCs. We compared SWCNT with biochar and charcoal on their effect on the microbial degradability of 0.05 mg kg(-1) (14)C-phenanthrene (PHE) by Mycobacterium vanbaalenii PYR-1 in two sediments with different organic carbon (OC) contents. When the amendment rate of SWCNT or BC was 1 mg g(-1), PHE mineralization was inhibited much more significantly by SWCNT than by either biochar or charcoal. After 360 h of incubation, the mineralized fraction of PHE in the presence of SWCNT was 59.5% of the non-amended control in the sediment with low OC content, and only 42.4% in the other sediment with a higher OC content. Analysis of the freely dissolved concentration (C (free)) using disposable polydimethylsiloxane (PDMS) fibers showed that SWCNT decreased C (free) by 85-95%, apparently due to preferential sorption of PHE to SWCNT particles that had a much larger specific surface area and pore volume than biochar or charcoal. However, pre-interaction of SWCNT with dissolved organic matter (peptone, tannic acid, and humic acid) led to attachment of polar functional groups and reduced surface area on SWCNT, resulting in decreased PHE sorption and an alleviated effect on PHE biodegradation in the order of peptone > tannic acid > humic acid.

[Modified retrograde rotative-type interlocking intramedullary nail for humeral shaft fractures]

OBJECTIVE

To improve the retrograde rotative-type interlocking intramedullary nail based on humeral bone dissection and clinical application, and investigate the clinical values of modified retrograde rotative-type interlocking intramedullary nail for humeral shaft fracture.

METHODS

Between March 2006 and March 2010, 146 patients with humeral shaft fractures were treated and fractures were fixed with the modified retrograde rotative-type interlocking intramedullary nail (the modified group, n=73) and with the retrograde rotative-type interlocking intramedullary nail (the original group, n=73). In the original group, there were 40 males and 33 females with an average age of 41 years; 41 cases were classified as transverse fracture, 18 as oblique fracture, 8 as spiral fracure, and 6 as comminuted fracture; the median disease duration was 11 days (range, 3 hours to 2 months); and close reduction fixation was performed in 27 cases and open reduction fixation in 46 cases. In the modified group, there were 39 males and 34 females with an average age of 40 years; 43 cases were classified as transverse fracture, 16 as oblique fracture, 10 as spiral fracure, and 4 as comminuted fracture; the median disease duration was 13 days (range, 3 hours to 3 months); and close reduction fixation was performed in 31 cases and open reduction fixation in 42 cases. There was no significant difference in sex, age, fracture type, and disease duration between 2 groups (P > 0.05). The fracture healing and functional recovery of affected limbs were compared between 2 groups after operation.

RESULTS

The operation time and intraoperative blood loss in the modified group were significantly less than those in the original group (P < 0.05). Iatrogenic fracture occurred in 3 cases of the original group, which were cleavage fracture of supracondylar. No iatrogenic fracture occurred in the modified group. All incisions of 2 groups healed by first intention without complications of postoperative infections, metal fracture, and loosening of internal fixation, etc. A total of 116 patients were followed up more than 12 months in 2 groups with 58 patients in each group. The fracture healing time was (15 +/- 3) weeks (fresh fracture) and (30 +/- 12) weeks (old fracture and nonunion) in the modified group, and was (16 +/- 4) weeks (fresh fracture) and (35 +/- 14) weeks (old fracture) in the original group, showing significant differences between 2 groups (P < 0.05). The results of Neer shoulder score were excellent in 65 cases and good in 8 cases, and the results of Aitken and Rorabeck elbow function score were excellent in 61 cases and good in 12 cases in the original group; the results of Neer shoulder score were excellent in 67 cases and good in 6 cases, and the results of Aitken and Rorabeck elbow function score were excellent in 63 cases and good in 10 cases; and the excellent and good rates were 100% in 2 groups.

CONCLUSION

The modified retrograde rotative-type interlocking intramedullary nail has the advantages of easy operation and less complication, which is an effective and reliable internal fixator.

Enzymatic single-chain antibody tagging: a universal approach to targeted molecular imaging and cell homing in cardiovascular disease

RATIONALE

Antibody-targeted delivery of imaging agents can enhance the sensitivity and accuracy of current imaging techniques. Similarly, homing of effector cells to disease sites increases the efficacy of regenerative cell therapy while reducing the number of cells required. Currently, targeting can be achieved via chemical conjugation to specific antibodies, which typically results in the loss of antibody functionality and in severe cell damage. An ideal conjugation technique should ensure retention of antigen-binding activity and functionality of the targeted biological component.

OBJECTIVE

To develop a biochemically robust, highly reproducible, and site-specific coupling method using the Staphylococcus aureus sortase A enzyme for the conjugation of a single-chain antibody (scFv) to nanoparticles and cells for molecular imaging and cell homing in cardiovascular diseases. This scFv specifically binds to activated platelets, which play a pivotal role in thrombosis, atherosclerosis, and inflammation.

METHODS AND RESULTS

The conjugation procedure involves chemical and enzyme-mediated coupling steps. The scFv was successfully conjugated to iron oxide particles (contrast agents for magnetic resonance imaging) and to model cells. Conjugation efficiency ranged between 50% and 70%, and bioactivity of the scFv after coupling was preserved. The targeting of scFv-coupled cells and nanoparticles to activated platelets was strong and specific as demonstrated in in vitro static adhesion assays, in a flow chamber system, in mouse intravital microscopy, and in in vivo magnetic resonance imaging of mouse carotid arteries.

CONCLUSIONS

This unique biotechnological approach provides a versatile and broadly applicable tool for procuring targeted regenerative cell therapy and targeted molecular imaging in cardiovascular and inflammatory diseases and beyond.

An activation-specific platelet inhibitor that can be turned on/off by medically used hypothermia

OBJECTIVE

Therapeutic hypothermia is successfully used, for example, in cardiac surgery to protect organs from ischemia. Cardiosurgical procedures, especially in combination with extracorporeal circulation, and hypothermia itself are potentially prothrombotic. Despite the obvious need, the long half-life of antiplatelet drugs and thus the risk of postoperative bleedings have restricted their use in cardiac surgery. We describe here the design and testing of a unique recombinant hypothermia-controlled antiplatelet fusion protein with the aim of providing increased safety of hypothermia, as well as cardiac surgery.

METHODS AND RESULTS

An elastin-mimetic polypeptide was fused to an activation-specific glycoprotein (GP) IIb/IIIa-blocking single-chain antibody. In silico modeling illustrated the sterical hindrance of a β-spiral conformation of elastin-mimetic polypeptide preventing the single-chain antibody from inhibiting GPIIb/IIIa at 37°C. Circular dichroism spectra demonstrated reverse temperature transition, and flow cytometry showed binding to and blocking of GPIIb/IIIa at hypothermic body temperature (≤32°C) but not at normal body temperature. In vivo thrombosis in mice was selectively inhibited at hypothermia but not at 37°C.

CONCLUSIONS

This is the first description of a broadly applicable pharmacological strategy by which the activity of a potential drug can be controlled by temperature. In particular, this drug steerability may provide substantial benefits for antiplatelet therapy.

Evidence of platelet activation at medically used hypothermia and mechanistic data indicating ADP as a key mediator and therapeutic target

OBJECTIVE

Hypothermia is used in various clinical settings to inhibit ischemia-related organ damage. However, prothrombotic effects have been described as potential side effects. This study aimed to elucidate the mechanism of hypothermia-induced platelet activation and subsequent prothrombotic events and to develop preventative pharmacological strategies applicable during clinically used hypothermia.

METHODS AND RESULTS

Platelet function was investigated ex vivo and in vivo at clinically used hypothermia (28°C/18°C). Hypothermic mice demonstrated increased expression of platelet activation marker P-selectin, platelet-leukocyte aggregate formation, and thrombocytopenia. Intravital microscopy of FeCl(3)-injured murine mesenteric arteries revealed increased platelet thrombus formation with hypothermia. Ex vivo flow chamber experiments indicated increased platelet-fibrinogen adhesion under hypothermia. We show that hypothermia results in reduced ADP hydrolysis via reduction of CD39 (E-NTPDase1) activity, resulting in increased levels of ADP and subsequent augmented primary and secondary platelet activation. In vivo administration of ADP receptor P(2)Y(12) antagonists and recombinant soluble CD39 prevented hypothermia-induced thrombus formation and thrombocytopenia, respectively.

CONCLUSIONS

The platelet agonist ADP plays a key role in hypothermia-induced platelet activation. Inhibition of receptor binding or hydrolysis of ADP has the potential to protect platelets against hypothermia-induced activation. Our findings provide a rational basis for further evaluation of novel antithrombotic strategies in clinically applied hypothermia.