Generation and rescue of a murine model of platelet dysfunction: the Bernard-Soulier syndrome

The human Bernard-Soulier syndrome is an autosomal recessive disorder of platelet dysfunction presenting with mild thrombocytopenia, circulating "giant" platelets and a bleeding phenotype. The bleeding in patients with the Bernard-Soulier syndrome is disproportionately more severe than suggested by the reduced platelet count and is explained by a defect in primary hemostasis owing to the absence of the platelet glycoprotein (GP) Ib-IX-V membrane receptor. However, the molecular basis for the giant platelet phenotype and thrombocytopenia have remained unresolved but assumed to be linked to an absent receptor complex. We have disrupted the gene encoding the alpha-subunit of mouse GP Ib-IX-V (GP Ibalpha) and describe a murine model recapitulating the hallmark characteristics of the human Bernard-Soulier syndrome. The results demonstrate a direct link between expression of a GP Ib-IX-V complex and normal megakaryocytopoiesis and platelet morphogenesis. Moreover, using transgenic technology the murine Bernard-Soulier phenotype was rescued by expression of a human GP Ibalpha subunit on the surface of circulating mouse platelets. Thus, an in vivo model is defined for analysis of the human GP Ib-IX-V receptor and its role in the processes performed exclusively by megakaryocytes and platelets.

Measles virus causes immunogenic cell death in human melanoma

Oncolytic viruses (OV) are promising treatments for cancer, with several currently undergoing testing in randomised clinical trials. Measles virus (MV) has not yet been tested in models of human melanoma. This study demonstrates the efficacy of MV against human melanoma. It is increasingly recognised that an essential component of therapy with OV is the recruitment of host antitumour immune responses, both innate and adaptive. MV-mediated melanoma cell death is an inflammatory process, causing the release of inflammatory cytokines including type-1 interferons and the potent danger signal HMGB1. Here, using human in vitro models, we demonstrate that MV enhances innate antitumour activity, and that MV-mediated melanoma cell death is capable of stimulating a melanoma-specific adaptive immune response.

An exploratory study of patients' perceptions, memories and experiences of an intensive care unit

In the research reported, 298 patients were asked to describe their memories of the Royal Melbourne Hospital's intensive care unit (ICU). The data were collected by either self-reported questionnaires or structured interviews and examined from a bio-psycho-social perspective using both qualitative and quantitative methods. These recollections demonstrate that the close surveillance by both technological support and health care practitioners provide many patients and their families with a feeling of safety. Patients' memories of ICU also highlighted the presence of power relations which are inherent in clinical practice. This paper provides examples of actions and remarks within ICU that were not only remembered by patients and their families but also continued to effect patients 6 months after their discharge. The data in this research indicate that some of the psychological problems experienced after discharge may have been prevented by improved communication between staff and patients in ICU. This study also demonstrated the importance of providing feedback to the nurses working in ICU. This feedback raised awareness of patients' perceptions of both ICU itself and the behaviour of the staff. It also reminded staff that some patients remember everything about their admission of ICU. The data indicate that while patients found the presence of good communication in ICU both therapeutic and reassuring, they found the lack of good communication distressing. Poor communication not only caused anxiety while the patient was in ICU but also contributed to less than optimal recoveries after discharge. Finally, it will be argued that the provision of information from nurses not only diminished feelings of anxiety but also empowered patients to become involved in decisions about their care.

Ability to pay for health care: concepts and evidence

In many developing countries people are expected to contribute to the cost of health care from their own pockets. As a result, people's ability to pay (ATP) for health care, or the affordability of health care, has become a critical policy issue in developing countries, and a particularly urgent issue where households face combined user fee burdens from various essential service sectors such as health, education and water. Research and policy debates have focused on willingness to pay (WTP) for essential services, and have tended to assume that WTP is synonymous with ATP. This paper questions this assumption, and suggests that WTP may not reflect ATP. Households may persist in paying for care, but to mobilize resources they may sacrifice other basic needs such as food and education, with serious consequences for the household or individuals within it. The opportunity costs of payment make the payment 'unaffordable' because other basic needs are sacrificed. An approach to ATP founded on basic needs and the opportunity costs of payment strategies (including non-utilization) is therefore proposed. From the few studies available, common household responses to payment difficulties are identified, ranging from borrowing to more serious 'distress sales' of productive assets (e.g. land), delays to treatment and, ultimately, abandonment of treatment. Although these strategies may have a devastating impact on livelihoods and health, few studies have investigated them in any detail. In-depth longitudinal household studies are proposed to develop understanding of ATP and to inform policy initiative which might contribute to more affordable health care.

Adipose atrophy in cancer cachexia: morphologic and molecular analysis of adipose tissue in tumour-bearing mice

Extensive loss of adipose tissue is a hallmark of cancer cachexia but the cellular and molecular basis remains unclear. This study has examined morphologic and molecular characteristics of white adipose tissue in mice bearing a cachexia-inducing tumour, MAC16. Adipose tissue from tumour-bearing mice contained shrunken adipocytes that were heterogeneous in size. Increased fibrosis was evident by strong collagen-fibril staining in the tissue matrix. Ultrastructure of 'slimmed' adipocytes revealed severe delipidation and modifications in cell membrane conformation. There were major reductions in mRNA levels of adipogenic transcription factors including CCAAT/enhancer binding protein alpha (C/EBPalpha), CCAAT/enhancer binding protein beta, peroxisome proliferator-activated receptor gamma, and sterol regulatory element binding protein-1c (SREBP-1c) in adipose tissue, which was accompanied by reduced protein content of C/EBPalpha and SREBP-1. mRNA levels of SREBP-1c targets, fatty acid synthase, acetyl CoA carboxylase, stearoyl CoA desaturase 1 and glycerol-3-phosphate acyl transferase, also fell as did glucose transporter-4 and leptin. In contrast, mRNA levels of peroxisome proliferators-activated receptor gamma coactivator-1alpha and uncoupling protein-2 were increased in white fat of tumour-bearing mice. These results suggest that the tumour-induced impairment in the formation and lipid storing capacity of adipose tissue occurs in mice with cancer cachexia.

Interaction of asialo von Willebrand factor with glycoprotein Ib induces fibrinogen binding to the glycoprotein IIb/IIIa complex and mediates platelet aggregation

von Willebrand factor (vWF) is necessary for the initial attachment of platelets to exposed subendothelium, particularly under flow conditions like those prevailing in the microcirculation. Little is known about its possible participation in subsequent events leading to formation of platelet thrombi at sites of vascular injury. We addressed this question by studying the mechanisms by which desialylated vWF induces platelet aggregation in the absence of any other stimulus. Asialo vWF, unlike the native molecule, does not require ristocetin to interact with platelets. Agglutination induced by ristocetin is largely independent of active platelet metabolism and only partially reflects physiological events. We have shown here that binding of asialo vWF to platelets was accompanied by release of dense granule content and subsequent ADP-dependent fibrinogen binding to receptors on the glycoprotein (GP) IIb/IIIa complex. The initial interaction of asialo vWF with platelets was mediated by GPIb, as shown by blocking obtained with monoclonal antibody. Inhibition of this initial interaction completely abolished platelet aggregation induced by asialo vWF. The same effect was obtained with a monoclonal anti-GPIIb/IIIa antibody. This, however, did not block asialo vWF binding to platelets, but rather inhibited subsequent fibrinogen binding induced by asialo vWF. Therefore, the latter process was also essential for platelet aggregation under the conditions described. At saturation, asialo vWF induced binding of between 3.2 and 27.7 X 10(3) fibrinogen molecules/platelet, with an apparent dissociation constant between 0.28 and 1.18 X 10(-6) M. This study shows that asialo, and possibly native, vWF acts as a platelet agonist after its binding to GPIb and induces aggregation through a pathway dependent on GPIIb/IIIa-related receptors.

Isolation of three separate anaphylatoxins from complement-activated human serum

Recent methodologies used in preparing anaphylatoxins from complement-activated serum are described. Activation of the alternative pathway generates C3a and C5a; however, activation of the classical pathway is required to generate the anaphylatoxin from C4. This article describes an activation scheme that simultaneously generates all three of the anaphylatoxins (e.g., C3a, C4a and C5a) in human serum and outlines a procedure for isolating each as homogeneous products. Purification of intact anaphylatoxins directly from complement-activated serum takes place only if an exopeptidase in serum, known as carboxypeptidase N (SCPN), is properly inhibited. A new series of mercapto derivatives of arginine analogs are introduced as potent and effective inhibitors of SCPN. These inhibitors permit normal complement activation but prevent degradation of the released activation fragments C3a, C4a or C5a. The SCPN inhibitor previously used was 6-aminohexanoic acid (EACA), but it required a 1 M concentration for effective inhibition, the substituted mercapto-guanido compounds prove to be effective in the mM range.

Clinical dosimetry using MOSFETs

PURPOSE

The use of metal oxide-silicon field effect transistors (MOSFETs) as clinical dosimeters is demonstrated for a number of patients with targets at different clinical sites.

METHODS AND MATERIALS

Commercially available MOSFETs were characterized for energy response, angular dependency of response, and effect of accumulated dose on sensitivity and some inherent properties of MOSFETs. The doses determined both by thermoluminescence dosimetry (TLD) and MOSFETs in clinical situation were evaluated and compared to expected doses determined by calculation.

RESULTS

It was observed that a standard calibration of 0.01 Gy/mV gave MOSFET determined doses which agreed with expected doses to within 5% at the 95% confidence limit for photon beams from 6 to 25 MV and electron beams from 5 to 14 MeV. An energy-dependent variation in response of up to 28% was observed between two orientations of a MOSFET. The MOSFET doses compared very well with the doses estimated by TLDs, and the patients tolerated MOSFETs very well. A standard deviation of 3.9% between expected dose and MOSFET determined dose was observed, while for TLDs the standard deviation was 5.1%. The advantages and disadvantages of using MOSFETs for clinical dosimetry are discussed in detail.

CONCLUSION

It was concluded that MOSFETs can be used as clinical dosimeters and can be a good alternative to TLDs. However, they have limitations under certain clinical situations.

Site-directed recombination in the genome of transgenic tobacco

The plant genome responds to the bacteriophage P1-derived loxP-Cre site-specific recombination system. Recombination took place at loxP sites stably integrated in the tobacco genome, indicating that the Cre recombinase protein, expressed by a chimeric gene also stably resident in the genome, was able to enter the nucleus and to locate a specific 34 bp DNA sequence. An excisional recombination event was monitored by the acquisition of kanamycin resistance, which resulted from the loss of a polyadenylation signal sequence that interrupted a chimeric neomycin phosphotransferase II gene. Molecular analysis confirmed that the excision had occurred. Recombination occurred when plants with the integrated loxP construction were stably re-transformed with a chimeric cre gene and when plants with the introduced loxP construction were cross-bred with those carrying the chimeric cre gene. As assayed phenotypically, site-specific recombination could be detected in 50%-100% of the plants containing both elements of the system. Kanamycin resistance was detected at 2-3 weeks after re-transformation and in the first leaf of hybrid seedlings. This demonstration of the effectiveness of the loxP-Cre system in plants provides the basis for development of this system for such purposes as directing site-specific integration and regulation of gene expression.

Targeted infection of human cells via major histocompatibility complex class I molecules by Moloney murine leukemia virus-derived viruses displaying single-chain antibody fragment-envelope fusion proteins

As an approach to cell targeting by retroviruses, the lack of which constitutes one major limitation of retroviral vector technology, we engineered the Moloney murine leukemia virus ecotropic envelope glycoprotein. When inserted between amino acids 6 and 7 of the latter, a single-chain antibody fragment (ScFv) specific for human major histocompatibility complex class I molecules was shown to be able to redefine the tropism of ecotropic Moloney murine leukemia virus-derived retroviral particles by allowing infection of major histocompatibility complex class I-positive human cells. At variance with other recently described experimental systems, the type of modification adopted here allowed targeted infection in the absence of coexpressed wild-type env-encoded protein molecules. Interestingly, the chimeric ScFv-env protein also retained the ability to recognize the ecotropic receptor and allowed infection of murine cells, albeit at a reduced efficiency.

Characterization of the adenovirus proteinase: substrate specificity

Peptides were synthesized based on the cleavage sites in the adenovirus type 2 proteins pVI and pVII. The synthetic peptides were incubated with disrupted, purified adenovirus as a source of proteinase and specific cleavages were monitored by fast protein liquid chromatography and amino acid analysis. Using this approach it was established that all the peptides cleaved were of the form M(L)XGX decreases G or M(L)XGG decreases X. Thus we have shown that the adenoviral proteinase recognizes a specific secondary structure formed by a sequence of at least five amino acids, the main determinants of specificity being two and four residues to the N-terminal side of the bond cleaved. We were able to examine the relevant structural features of the peptide substrates by utilizing the CHEM-X molecular modelling package. Using our consensus sequence we were able to predict the cleavage sites in the viral proteins pVIII, pre-terminal protein (pTP), 11K and IIIa. Octapeptides containing the predicted sites in pVIII and the pTP were synthesized and shown to be cleaved by the proteinase.

User fee policies to promote health service access for the poor: a wolf in sheep's clothing?

An international survey of health service user fee and exemption policies in 26 low- and middle-income countries assessed whether user fee policies were supported by measures that protect the poor. In particular, it explored whether governments were introducing a package of supportive measures to promote service improvements that benefit disadvantaged groups and tackle differential ability to pay through an effective series of exemptions. The results show that many countries lack policies that promote access for disadvantaged groups within user fee systems and quality improvements such as revenue retention at the health care facility and expenditure guidelines for local managers. More significant policy failures were identified for exemptions: 27 percent of countries had no policy to exempt the poor; in contrast, health workers were exempted in 50 percent of countries. Even when an official policy to exempt the poor existed, there were numerous informational, administrative, economic, and political constraints to effective implementation of these exemptions. The authors argue that user fee policy should be developed more cautiously and in a more informed environment. Fees are likely to exacerbate existing inequities in health care financing unless exemptions policy can effectively reach those unable to pay.

Persistence of dormant tumor cells in the bone marrow of tumor cell-vaccinated mice correlates with long-term immunological protection

Live proliferation-competent and irradiated proliferation-incompetent L5178 murine lymphoma cells (Eb cell line) were compared for their potency to induce systemic anti-tumor immunity in syngeneic DBA/2 mice. The tumorigenic potential in vivo of live Eb cells was suppressed through local secretion of interleukin 4 (IL4) or alternatively by injection of parental cells at a site refractory to tumor growth. Inoculation of nontumorigenic doses of live Eb or Eb-IL4 cells led to long-lasting specific and systemic T-cell-mediated antitumor response requiring both CD4+ and CD8+ T lymphocytes. Irradiated cells offered only limited short-term protection, which could be marginally improved by IL4. The more effective protection offered by vaccination with live tumor cells correlated with rapid migration and persistence of tumor cells in the bone marrow of host animals after tumor cell inoculation. In contrast, irradiated Eb-lacZ cells had a short persistence. Tumor cells recovered from the bone marrow of host animals injected with live Eb-IL4 cells still expressed IL4. These observations indicate that in the course of vaccination with live Eb or Eb-IL4 cells, a fraction of these cells escaped destruction by host mechanisms and persisted in a dormant state in the bone marrow for long periods of time. Persistence of dormant tumor in the bone marrow correlated with the duration of anti-tumor immunity.

Metastatic cutaneous squamous cell carcinoma derived from actinic keratosis

BACKGROUND

Squamous cell carcinoma (SCC) with histologically contiguous actinic keratosis has long been thought of as a tumor with minimal risk for metastasis. The objective of this study was to determine if contiguous actinic keratosis is present in the original tumors of metastatic cutaneous SCC and to describe the histologic features of these tumors.

METHODS

The primary lesions of 22 patients with metastatic cutaneous SCC were examined using light microscopy.

RESULTS

Contiguous actinic keratosis was present histologically in 44% of the original lesions of cutaneous SCC that metastasized. The average tumor thickness was 6.6 mm. Greater than 66% of the tumors were well or moderately differentiated. The skin adjacent to the tumors showed solar degeneration in almost all instances.

CONCLUSIONS

The histologic presence of contiguous actinic keratosis is not a useful predictor of the metastatic behavior of cutaneous SCC. Increased tumor thickness and depth of invasion are the most consistent histopathologic features of cutaneous SCC that metastasize.

Platelet glycoprotein VI facilitates experimental lung metastasis in syngenic mouse models

BACKGROUND

Glycoprotein (GP)VI is a key receptor for collagen on the platelet surface. It is a member of the immunoglobulin superfamily and is uniquely expressed on the surface of platelets, where it is assembled with the immunoreceptor tyrosine activation motif subunit, FcR-gamma. We have previously reported the generation of a murine model of GPVI deficiency that revealed profound defects in collagen-induced platelet aggregation and in platelet activation following adhesion to collagen. Beyond the hemostasis/thrombosis paradigm, platelet receptors are emerging as significant participants in tumorigenesis and inflammation.

OBJECTIVE

In the current study, we have evaluated a role for platelet GPVI in primary tumor growth and experimental metastasis.

METHODS

Primary tumor induction and experimental metastasis assays were performed using syngenic immunocompetent animals and tumor cells derived from the C57BL/6J mouse strain in wild-type (C57BL/6J) and N10 C57BL/6J congenic GPVI-deficient mice.

RESULTS

Using either a Lewis lung carcinoma (D121) or melanoma (B16F10.1) cell line, we observed an approximately 50% reduction in the number of visible tumor foci in GPVI-deficient mice as compared with control C57BL/6J mice. Additional studies were performed to compare the size of subcutaneously implanted tumor cells, that is, primary tumor growth. Here, we observed no noticeable size difference when comparing the presence or absence of platelet GPVI.

CONCLUSIONS

The results demonstrate that the presence of platelet GPVI facilitates experimental tumor metastasis but does not contribute to the growth of primary tumors.

The role of citizen science in addressing grand challenges in food and agriculture research

The power of citizen science to contribute to both science and society is gaining increased recognition, particularly in physics and biology. Although there is a long history of public engagement in agriculture and food science, the term 'citizen science' has rarely been applied to these efforts. Similarly, in the emerging field of citizen science, most new citizen science projects do not focus on food or agriculture. Here, we convened thought leaders from a broad range of fields related to citizen science, agriculture, and food science to highlight key opportunities for bridging these overlapping yet disconnected communities/fields and identify ways to leverage their respective strengths. Specifically, we show that (i) citizen science projects are addressing many grand challenges facing our food systems, as outlined by the United States National Institute of Food and Agriculture, as well as broader Sustainable Development Goals set by the United Nations Development Programme, (ii) there exist emerging opportunities and unique challenges for citizen science in agriculture/food research, and (iii) the greatest opportunities for the development of citizen science projects in agriculture and food science will be gained by using the existing infrastructure and tools of Extension programmes and through the engagement of urban communities. Further, we argue there is no better time to foster greater collaboration between these fields given the trend of shrinking Extension programmes, the increasing need to apply innovative solutions to address rising demands on agricultural systems, and the exponential growth of the field of citizen science.

Blood island formation in attached cultures of murine embryonic stem cells

Differentiation of murine embryonic stem cells in suspension culture results in the formation of cystic embryoid bodies that develop blood islands. In this study pre-cystic embryoid bodies were attached to a substratum, and the program of differentiation was monitored. The attached ES cell cultures formed blood islands on a cell layer that migrated out from the center of attachment and beneath a mesothelial-like cell layer. Morphological and in situ marker analysis showed benzidine-positive hematopoietic cells surrounded by vascular endothelial cells that expressed PECAM and took up DiI-Ac-LDL. Waves of morphological differentiation were evident, suggesting a graded response to differentiation signals. Electron microscopy of the blood islands showed that they were similar to blood islands of cystic embryoid bodies and mouse yolk sacs, and cell-cell junctions were evident among the blood island cells. RNA expression analysis was consistent with the presence of hematopoietic precursor cells of several lineages and a primitive vascular endothelium in the cultures. Thus a program of vascular and hematopoietic development can be elaborated in attached ES cell cultures, and these blood islands are accessible to experimental manipulation.

Outcome in prenatally diagnosed fetal agenesis of the corpus callosum

This study of the outcome and prognostic factors in prenatally diagnosed agenesis of the corpus callosum (ACC) was undertaken to see if there are any differences between subgroups, what relationship they have to neurodevelopmental outcome and whether this information aids the counselling of parents of fetuses with the condition. The outcome of 14 prenatally diagnosed fetuses with ACC and 61 postnatally diagnosed patients was assessed in terms of clinical problems, developmental milestones and neurological signs; each patient was then given a score out of 10, 0 being a normal outcome and 10 being the worst outcome, i.e. death or termination of pregnancy. Comparing patients diagnosed pre- and postnatally, several similarities were found indicating that the postnatal group can provide useful information about the prenatal group. There was a higher incidence of ACC in males than females. In the prenatally diagnosed patients complete ACC was more common than partial ACC, although this might be because partial ACC was easily missed. Complete ACC has a worse prognosis than partial ACC (p = 0.001), and when associated with other anomalies, especially of the central nervous system, the outcome is very bad (p < 0.01). The only neurodevelopmentally normal patients were in the isolated partial ACC group. This study highlights the need to perform a detailed review of fetal anatomy and the desirability of determining the karyotype of the fetus in all newly diagnosed cases of ACC so that as much information as possible is available before parents are counselled about the likely outcome.

The Drosophila SOX-domain protein Dichaete is required for the development of the central nervous system midline

SOX-domain proteins are a class of developmentally important transcriptional regulators related to the mammalian testis determining factor SRY. In common with other SOX-domain genes, the Drosophila Dichaete gene has a dynamic expression profile in the developing central nervous system, including cells of the ventral midline. We find defects in the differentiation of midline glia and concomitant axonal defects in Dichaete mutants that are rescued by driving Dichaete expression in the midline. Since Dichaete is required for the correct specification or differentiation of midline glia, we have used the ventral midline as a model system to study SOX gene function in vivo and demonstrate a genetic interaction between Dichaete and the POU domain gene ventral veinless. In mammals, a protein related to Dichaete, SOX2, also interacts with POU transcription factors. The midline phenotypes of Dichaete mutations are rescued by expression of mouse SOX2. Our data suggest that SOX gene structure, function and interactions have been conserved during evolution.

The value of ultrasonic examination of the lumbar spine in infants with specific reference to cutaneous markers of occult spinal dysraphism

AIM

To present part of the rationale behind the recent update to the M12 guideline in The Royal College of Radiologists' publication "Making the best use of a department of clinical radiology", 4th edition 1998, which stated that ultrasound was useful in screening for dysraphism in infants with cutaneous markers such as sacral dimple or hairy patch.

MATERIALS AND METHODS

Over a 10-year period a total of 223 infant lumbar spines were scanned, for various clinical indications. Forty of these patients had already had abnormalities detected antenatally by foetal ultrasonography. One hundred and eight-three patients had abnormalities detected on postnatal clinical examination; most of these had various cutaneous markers, some had other congenital abnormalities.

RESULTS

There were a total of 29 patients with dysraphism; 24 were detected antenatally and five postnatally. Of the five, two had two or more cutaneous markers and three had anorectal anomalies. All 86 of the patients with simple sacral dimples, pits or sinuses were normal.

CONCLUSION

As an isolated abnormality, simple dimples or pits are not useful markers of spinal dysraphism. The authors suggest a new imaging protocol, resulting in improved diagnostic efficiency.

Life expectancy associated with different ages at diagnosis of type 2 diabetes in high-income countries: 23 million person-years of observation

BACKGROUND

The prevalence of type 2 diabetes is increasing rapidly, particularly among younger age groups. Estimates suggest that people with diabetes die, on average, 6 years earlier than people without diabetes. We aimed to provide reliable estimates of the associations between age at diagnosis of diabetes and all-cause mortality, cause-specific mortality, and reductions in life expectancy.

METHODS

For this observational study, we conducted a combined analysis of individual-participant data from 19 high-income countries using two large-scale data sources: the Emerging Risk Factors Collaboration (96 cohorts, median baseline years 1961-2007, median latest follow-up years 1980-2013) and the UK Biobank (median baseline year 2006, median latest follow-up year 2020). We calculated age-adjusted and sex-adjusted hazard ratios (HRs) for all-cause mortality according to age at diagnosis of diabetes using data from 1 515 718 participants, in whom deaths were recorded during 23·1 million person-years of follow-up. We estimated cumulative survival by applying age-specific HRs to age-specific death rates from 2015 for the USA and the EU.

FINDINGS

For participants with diabetes, we observed a linear dose-response association between earlier age at diagnosis and higher risk of all-cause mortality compared with participants without diabetes. HRs were 2·69 (95% CI 2·43-2·97) when diagnosed at 30-39 years, 2·26 (2·08-2·45) at 40-49 years, 1·84 (1·72-1·97) at 50-59 years, 1·57 (1·47-1·67) at 60-69 years, and 1·39 (1·29-1·51) at 70 years and older. HRs per decade of earlier diagnosis were similar for men and women. Using death rates from the USA, a 50-year-old individual with diabetes died on average 14 years earlier when diagnosed aged 30 years, 10 years earlier when diagnosed aged 40 years, or 6 years earlier when diagnosed aged 50 years than an individual without diabetes. Using EU death rates, the corresponding estimates were 13, 9, or 5 years earlier.

INTERPRETATION

Every decade of earlier diagnosis of diabetes was associated with about 3-4 years of lower life expectancy, highlighting the need to develop and implement interventions that prevent or delay the onset of diabetes and to intensify the treatment of risk factors among young adults diagnosed with diabetes.

FUNDING

British Heart Foundation, Medical Research Council, National Institute for Health and Care Research, and Health Data Research UK.

Selective transduction of protease-rich tumors by matrix-metalloproteinase-targeted retroviral vectors

We recently showed that retroviral vectors can be targeted through protease substrate interactions. Infectivity is blocked by a polypeptide fused to the viral envelope glycoprotein (SU) and is restored when a protease cleaves the connecting linker, releasing the inhibitory polypeptide from the viral surface. Protease specificity is achieved by engineering the sequence of the linker. Here, using two different matrix-metalloproteinase (MMP)-activatable vectors, we demonstrated highly efficient and selective transduction of MMP-rich target cells in a heterogeneous cell population. In vivo, the MMP-targeted vectors showed strong selectivity for MMP-rich tumor xenografts. Protease-activatable vectors offer new possibilities for in vivo targeting of gene delivery.