Development of a reliable surgical quality assurance tool for gastrectomy in oncological trials.

BACKGROUND: Despite its recognized importance, there is currently no reliable tool for surgical quality assurance (SQA) of gastrectomy in surgical oncology. The aim of this study was to develop an SQA tool for gastrectomy and to apply this tool within the ADDICT Trial in order to assess the extent and completeness of lymphadenectomy. METHODS: The operative steps for D1+ and D2 gastrectomy have been previously described in the literature and ADDICT trial manual. Two researchers also performed fieldwork in the UK and Japan to document key operative steps through photographs and semi-structured interviews with expert surgeons. This provided the steps that were used as the framework for the SQA tool. Sixty-two photographic cases from the ADDICT Trial were rated by three independent surgeons. Generalizability (G) theory determined inter-rater reliability. D-studies examined the effect of varying the number of assessors and photographic series they rated. Chi-square assessed intra-rater reliability, comparing how the individual assessor's responses corresponded to their global rating for extent of lymphadenectomy. RESULTS: The tool comprised 20 items, including 19 anatomical landmarks and a global rating score. Overall reliability had G-coefficient of 0.557. Internal consistency was measured with a Cronbach's alpha score of 0.869 and Chi-square confirmed intra-rater reliability for each assessor as < 0.05. CONCLUSIONS: A photographic surgical quality assurance tool is presented for gastrectomy. Using this tool, the assessor can reliably determine not only the quality but also the extent of the lymphadenectomy performed based on remaining anatomy rather than the excised specimen.

The role of non-placental signals in the adaptation of islets to pregnancy.

It is well established that the maternal ß-cell mass increases during pregnancy in both humans and rodents to compensate insulin resistance and increased metabolic demand, and rapidly returns to normal levels post-partum. However, the mechanisms underlying this adaptation are not well understood. It is established that this process is driven partly by placental signals, but the contribution of non-placental signals is still unclear. This study aimed to differentiate between the role of placental and non-placental signals in regulating the ß-cell mass and glucose homeostasis during and after pregnancy. Pseudopregnant, pregnant and lactating mice were used to study the effects of maternal hormones on ß-cell function during early pregnancy, mid-to-late pregnancy and post-partum, respectively. Pseudopregnant mice, with circulating hormone levels mirroring those during pregnancy but lacking placental signals, had significantly increased ß-cell proliferation compared to non-pregnant controls but no change in glucose homeostasis, suggesting a role for non-placental hormones in increasing ß-cell mass. The rate of ß-cell proliferation rate dropped immediately after parturition, but lactating mice still had a significantly higher rate of ß-cell proliferation compared to non-lactating post-partum mice, suggesting that lactation-related hormones play a role in the controlled involution of ß-cell mass post-partum. These results implicate a role for both non-placental and placental signals in regulating ß-cell mass during and after pregnancy.

Paediatric estimated average glucose in children with Type 1 diabetes.

AIM: Estimated average glucose has been used to transform HbA1c into a glucose measure that might better inform patients of their glycaemic control. The data set used to obtain the estimated average glucose equation was derived in adults with Type 1 and Type 2 diabetes, along with normal healthy control subjects, and requires testing in children. METHODS: This was a cross-sectional study of 234 children and young people (106 male) with Type 1 diabetes aged 4.0-23.5 years who underwent continuous glucose monitoring over a 5-day period along with a measure of HbA1c . Regression analysis was used to determine estimated average glucose and agreement was assessed with the average glucose estimated from the Nathan equation: Nathan average glucose equation = 1.59 (HbA1c% ) - 2.59. RESULTS: Mean HbA1c was 76 mmol/mol (25.1) [9.1 (2.3)%] and mean continuous glucose monitoring tissue glucose was 10.4 (2.6) mmol/l. The relationship between continuous glucose monitoring tissue glucose and HbA1c was described by the paediatric equation: paediatric estimated average glucose = 0.49 (HbA1c %) + 5.95 (r = 0.45; P < 0.001). The mean paediatric estimated average glucose was 10.4 (1.1) mmol/l compared with that from the Nathan average glucose equation of 11.9 (3.7) mmol/l (P < 0.001). Overall, the paediatric estimated average glucose was 2.7 mmol/l lower than the Nathan estimated average glucose, with a 95% limit of agreement of ± 0.5 mmol/l. The agreement was very close with HbA1c values below 80 mmol/mol (9.5%). CONCLUSION: These data suggest that the Nathan estimated average glucose could be used in children and young people with Type 1 diabetes. Caution should still be exercised in the estimates derived for average glucose as the data set is skewed in both Nathan and paediatric average glucose estimates in opposite directions because of the differences in average HbA1c .

Nutrient dynamics of 12 Sphagnum species during establishment on a rewetted bog.

Peatland degradation through drainage and peat extraction have detrimental environmental and societal consequences. Rewetting is an option to restore lost ecosystem functions, such as carbon storage, biodiversity and nutrient sequestration. Peat mosses (Sphagnum) are the most important peat-forming species in bogs. Most Sphagnum species occur in nutrient-poor habitats; however, high growth rates have been reported in artificial nutrient-rich conditions with optimal water supply. Here, we demonstrate the differences in nutrient dynamics of 12 Sphagnum species during their establishment in a 1-year field experiment at a Sphagnum paludiculture area in Germany. The 12 species are categorized into three groups (slower-, medium- and fast-growing). Establishment of peat mosses is facilitated by constant supply of nutrient-rich, low pH, and low alkalinity surface water. Our study shows that slower-growing species (S. papillosum, S. magellancium, S. fuscum, S. rubellum, S. austinii; often forming hummocks) displayed signs of nutrient imbalance. These species accumulated higher amounts of N, P, K and Ca in their capitula, and had an elevated stem N:K quotient (>3). Additionally, this group sequestered less C and K per m2 than the fast and medium-growing species (S. denticulatum, S. fallax, S. riparium, S. fimbriatum, S. squarrosum, S. palustre, S. centrale). Lower lawn thickness may have amplified negative effects of flooding in the slower-growing species. We conclude that nutrient dynamics and carbon/nutrient sequestration rates are species-specific. For bog restoration, generating ecosystem services or choosing suitable donor material for Sphagnum paludiculture, it is crucial to consider their compatibility with prevailing environmental conditions.

Protection of MP-12-vaccinated rhesus macaques against parenteral and aerosol challenge with virulent rift valley fever virus.

To test safety and efficacy of the Rift Valley fever MP-12 (RVF MP-12) vaccine, 9 healthy adult Rhesus macaques, weighing 5-10 kg, were inoculated intramuscularly with 6 × 10(3) plaque forming units (PFUs) of MP-12 vaccine. The monkeys developed neutralizing antibody responses with no adverse effects other than a transient, low-titer viremia in 3 monkeys. Four vaccinated animals challenged intravenously with 3 × 10(6) PFUs of virulent Rift Valley fever virus strain ZH-501 (RVFV ZH-501) at 126 days after vaccination were protected against infection. The remaining 5 vaccinated monkeys along with 2 monkeys that had been vaccinated 6 years prior were completely protected against a small particle aerosol challenge of 5 × 10(5) PFUs of RVFV ZH-501. The mutagen-attenuated RVF MP-12 vaccine was determined to be protective against intravenous and aerosol challenge with virulent RVFV in these macaques, which suggests further development as a vaccine for humans is warranted.

Mucosal immunization of rhesus macaques with Rift Valley Fever MP-12 vaccine.

Rhesus macaques given 5 × 10(4) or 1 × 10(5) plaque-forming units (pfu) of Rift Valley fever (RVF) MP-12 vaccine by oral, intranasal drops, or small particle aerosol showed no adverse effects up to 56 days after administration. All monkeys given the vaccine by aerosol or intranasal drops developed 80% plaque reduction neutralization titers of ≥ 1:40 by day 21 after inoculation. Only 2 of 4 monkeys given the vaccine by oral instillation developed detectable neutralizing antibodies. All monkeys vaccinated by mucosal routes that developed detectable neutralizing antibodies were protected against viremia when challenged with 1 × 10(5) pfu of virulent RVF virus delivered by a small particle aerosol at 56 days after vaccination. A single inoculation of the RVF MP-12 live attenuated vaccine by the aerosol or intranasal route may provide an alternative route of protective immunization to RVFV in addition to conventional intramuscular injection.

Pressurised intraperitoneal aerosolised chemotherapy (PIPAC) for gastric cancer with peritoneal metastases: A systematic review by the PIPAC UK collaborative.

INTRODUCTION: Gastric cancer with peritoneal metastases (GCPM) carries a poor prognosis. Pressurised Intraperitoneal Aerosolised Chemotherapy (PIPAC) offers pharmacokinetic advantages over intravenous therapy, resulting in higher chemotherapy concentrations in peritoneal deposits, and potentially reduced systemic absorption/toxicity. This review evaluates efficacy, tolerability and impact on quality of life (QOL) of PIPAC for GCPM. METHODS: Following registration with PROSPERO (CRD42021281500), MEDLINE, EMBASE and The Cochrane Library were searched for PIPAC in patients with peritoneal metastases, in accordance with PRISMA standards RESULTS: Across 18 included reports representing 751 patients with GCPM (4 prospective, 11 retrospective, 3 abstracts, no phase III studies), median overall survival (mOS) was 8 - 19.1 months, 1-year OS 49.8-77.9%, complete response (PRGS1) 0-35% and partial response (PRGS2/3) 0-83.3%. Grade 3 and 4 toxicity was 0.7-25% and 0-4.1% respectively. Three studies assessing QOL reported no significant difference. CONCLUSION: PIPAC may offer promising survival benefits, toxicity, and QOL for GCPM.

Rift Valley fever MP-12 vaccine elicits an early protective immune response in mice.

Rift Valley fever virus (RVFV) is an important mosquito-borne pathogen that causes outbreaks of severe disease in people and livestock throughout Africa and the Arabian Peninsula. The development of an effective veterinary and human vaccine to protect against Rift Valley fever (RVF) disease remains a high priority. The live attenuated RVFV MP-12 is a promising vaccine candidate for the prevention of RVF in both human and domestic ruminants. The aim of this study was to determine the onset of protective immunity elicted in mice by a single dose of this vaccine. Groups of CD-1 mice were vaccinated intraperitoneally with RVFV MP-12 vaccine and challenged on days 2, 5, 6 and 7 post-vaccination (PV) with a lethal dose of virulent RVFV. The mice were observed once daily for terminal morbidity and blood samples were obtained from the retro-orbital sinus complex on days 23 and 28 PV of surviving mice to determine RVFV neutralizing antibody titers. In one test, 2 of 3 mice challenged on day 2 PV survived and all 3 mice challenged at days 5 and 7 PV also survived. A second test of 10 mice per group was performed, and half (5) of those challenged at day 2 PV survived while all (10) survived challenge at day 4 and 6 PV. All surviving animals develop antibody that ranged from 1:80 to 1:1,280 PV. In a separate experiment, RVFV MP-12 vaccinated CD-1 mice, but not challenged developed a low viremia for the first 3 days PV and neutralzing antibody was detected on days 5 through day 28 PV. These findings demonstrated that the RVFV MP-12 vaccine elicited a rapid protective immune response in mice as early as 2 days PV, thus further supporting the effectiveness of this vaccine candidate for preventing RVF among humans and domestic ruminants.

Rift Valley fever virus NSs protein promotes post-transcriptional downregulation of protein kinase PKR and inhibits eIF2alpha phosphorylation.

Rift Valley fever virus (RVFV) (genus Phlebovirus, family Bunyaviridae) is a negative-stranded RNA virus with a tripartite genome. RVFV is transmitted by mosquitoes and causes fever and severe hemorrhagic illness among humans, and fever and high rates of abortions in livestock. A nonstructural RVFV NSs protein inhibits the transcription of host mRNAs, including interferon-beta mRNA, and is a major virulence factor. The present study explored a novel function of the RVFV NSs protein by testing the replication of RVFV lacking the NSs gene in the presence of actinomycin D (ActD) or alpha-amanitin, both of which served as a surrogate of the host mRNA synthesis suppression function of the NSs. In the presence of the host-transcriptional inhibitors, the replication of RVFV lacking the NSs protein, but not that carrying NSs, induced double-stranded RNA-dependent protein kinase (PKR)-mediated eukaryotic initiation factor (eIF)2alpha phosphorylation, leading to the suppression of host and viral protein translation. RVFV NSs promoted post-transcriptional downregulation of PKR early in the course of the infection and suppressed the phosphorylated eIF2alpha accumulation. These data suggested that a combination of RVFV replication and NSs-induced host transcriptional suppression induces PKR-mediated eIF2alpha phosphorylation, while the NSs facilitates efficient viral translation by downregulating PKR and inhibiting PKR-mediated eIF2alpha phosphorylation. Thus, the two distinct functions of the NSs, i.e., the suppression of host transcription, including that of type I interferon mRNAs, and the downregulation of PKR, work together to prevent host innate antiviral functions, allowing efficient replication and survival of RVFV in infected mammalian hosts.

Rift valley fever virus L protein forms a biologically active oligomer.

Rift Valley fever virus (RVFV) (genus Phlebovirus, family Bunyaviridae) causes mosquito-borne epidemic diseases in humans and livestock. The virus carries three RNA segments, L, M, and S, of negative or ambisense polarity. L protein, an RNA-dependent RNA polymerase, encoded in the L segment, and N protein, encoded in the S segment, exert viral RNA replication and transcription. Coexpression of N, hemagglutinin (HA)-tagged L, and viral minigenome resulted in minigenome replication and transcription, a finding that demonstrated HA-tagged L was biologically active. Likewise L tagged with green fluorescent protein (GFP) was biologically competent. Coimmunoprecipitation analysis using extracts from cells coexpressing HA-tagged L and GFP-tagged L showed the formation of an L oligomer. Bimolecular fluorescence complementation analysis and coimmunoprecipitation studies demonstrated the formation of an intermolecular L-L interaction through its N-terminal and C-terminal regions and also suggested an intramolecular association between the N-terminal and C-terminal regions of L protein. A biologically inactive L mutant, in which the conserved signature SDD motif was replaced by the amino acid residues GNN, exhibited a dominant negative phenotype when coexpressed with wild-type L in the minigenome assay system. Expression of this mutant L also inhibited viral gene expression in virus-infected cells. These data provided compelling evidence for the importance of oligomerization of RVFV L protein for its polymerase activity.

Designing a therapeutic hepatitis B vaccine to circumvent immune tolerance.

An effective prophylactic hepatitis B virus (HBV) vaccine has long been available but is ineffective for chronic infection. The primary cause of chronic hepatitis B (CHB) and greatest impediment for a therapeutic vaccine is the direct and indirect effects of immune tolerance to HBV antigens. The resulting defective CD4+/CD8+ T cell response, poor cytokine production, insufficient neutralizing antibody (nAb) and poor response to HBsAg vaccination characterize CHB infection. The objective of this study was to develop virus-like-particles (VLPs) that elicit nAb to prevent viral spread and prime CD4+/CD8+ T cells to eradicate intracellular HBV. Eight neutralizing B cell epitopes from the envelope PreS1 region were consolidated onto a species-variant of the HBV core protein, the woodchuck hepatitis core antigen (WHcAg). PreS1-specific B cell epitopes were chosen because of preferential expression on HBV virions. Because WHcAg and HBcAg are not crossreactive at the B cell level and only partially cross-reactive at the CD4+/CD8+ T cell level, CD4+ T cells specific for WHcAg-unique T cell sites can provide cognate T-B cell help for anti-PreS1 Ab production that is not curtailed by immune tolerance. Immunization of immune tolerant HBV transgenic (Tg) mice with PreS1-WHc VLPs elicited levels of high titer anti-PreS1 nAbs equivalent to wildtype mice. Passive transfer of PreS1 nAbs into human-liver chimeric mice prevented acute infection and cleared serum HBV from mice previously infected with HBV in a model of CHB. At the T cell level, PreS1-WHc VLPs and hybrid WHcAg/HBcAg DNA immunogens elicited HBcAg-specific CD4+ Th and CD8+ CTL responses.

Generation and validation of a revised classification for oesophageal and junctional adenocarcinoma.

BACKGROUND: Oesophageal adenocarcinoma is the commonest oesophageal malignancy in the West, but is staged using a system designed for squamous cell carcinoma. The aim was to develop and validate a staging system for oesophageal and junctional adenocarcinoma. METHODS: Patients with oesophageal adenocarcinoma (Siewert types I and II) undergoing oesophagectomy with curative intent were randomly assigned to generation (313 patients) and validation (131) data sets. Outcome in the generation data set was associated with histopathological features; a revised node (N) classification was derived using recursive partitioning and tested on the validation data set. RESULTS: A revised N classification based on number of involved lymph nodes (N0, none; N1, one to five; N2, six or more) was prognostically significant (P < 0.001). Patients with involved nodes on both sides of the diaphragm, regardless of number, had the same outcome as the N2 group. When applied to the validation data set, the revised classification (including nodal number and location) provided greater discrimination between node-positive patients than the existing system (P < 0.001). CONCLUSION: A revised N classification based on number and location of involved lymph nodes provides improved prognostic power and incorporates features that may be useful before surgery in clinical management decisions.

Climate and satellite indicators to forecast Rift Valley fever epidemics in Kenya.

All known Rift Valley fever virus outbreaks in East Africa from 1950 to May 1998, and probably earlier, followed periods of abnormally high rainfall. Analysis of this record and Pacific and Indian Ocean sea surface temperature anomalies, coupled with satellite normalized difference vegetation index data, shows that prediction of Rift Valley fever outbreaks may be made up to 5 months in advance of outbreaks in East Africa. Concurrent near-real-time monitoring with satellite normalized difference vegetation data may identify actual affected areas.

Genetic identification of a hantavirus associated with an outbreak of acute respiratory illness.

A mysterious respiratory illness with high mortality was recently reported in the southwestern United States. Serologic studies implicated the hantaviruses, rodent-borne RNA viruses usually associated elsewhere in the world with hemorrhagic fever with renal syndrome. A genetic detection assay amplified hantavirus-specific DNA fragments from RNA extracted from the tissues of patients and deer mice (Peromyscus maniculatus) caught at or near patient residences. Nucleotide sequence analysis revealed the associated virus to be a new hantavirus and provided a direct genetic link between infection in patients and rodents.

Nipah virus: a recently emergent deadly paramyxovirus.

A paramyxovirus virus termed Nipah virus has been identified as the etiologic agent of an outbreak of severe encephalitis in people with close contact exposure to pigs in Malaysia and Singapore. The outbreak was first noted in late September 1998 and by mid-June 1999, more than 265 encephalitis cases, including 105 deaths, had been reported in Malaysia, and 11 cases of encephalitis or respiratory illness with one death had been reported in Singapore. Electron microscopic, serologic, and genetic studies indicate that this virus belongs to the family Paramyxoviridae and is most closely related to the recently discovered Hendra virus. We suggest that these two viruses are representative of a new genus within the family Paramyxoviridae. Like Hendra virus, Nipah virus is unusual among the paramyxoviruses in its ability to infect and cause potentially fatal disease in a number of host species, including humans.

NSm protein of Rift Valley fever virus suppresses virus-induced apoptosis.

Rift Valley fever virus (RVFV) is a member of the genus Phlebovirus within the family Bunyaviridae. It can cause severe epidemics among ruminants and fever, myalgia, a hemorrhagic syndrome, and/or encephalitis in humans. The RVFV M segment encodes the NSm and 78-kDa proteins and two major envelope proteins, Gn and Gc. The biological functions of the NSm and 78-kDa proteins are unknown; both proteins are dispensable for viral replication in cell cultures. To determine the biological functions of the NSm and 78-kDa proteins, we generated the mutant virus arMP-12-del21/384, carrying a large deletion in the pre-Gn region of the M segment. Neither NSm nor the 78-kDa protein was synthesized in arMP-12-del21/384-infected cells. Although arMP-12-del21/384 and its parental virus, arMP-12, showed similar growth kinetics and viral RNA and protein accumulation in infected cells, arMP-12-del21/384-infected cells induced extensive cell death and produced larger plaques than did arMP-12-infected cells. arMP-12-del21/384 replication triggered apoptosis, including the cleavage of caspase-3, the cleavage of its downstream substrate, poly(ADP-ribose) polymerase, and activation of the initiator caspases, caspase-8 and -9, earlier in infection than arMP-12. NSm expression in arMP-12-del21/384-infected cells suppressed the severity of caspase-3 activation. Further, NSm protein expression inhibited the staurosporine-induced activation of caspase-8 and -9, demonstrating that other viral proteins were dispensable for NSm's function in inhibiting apoptosis. RVFV NSm protein is the first identified Phlebovirus protein that has an antiapoptotic function.

Hydrogen storage in sH hydrates: a Monte Carlo study.

Grand canonical Monte Carlo simulations are performed to evaluate the hydrogen-storage capacity of the recently discovered hydrogen hydrates of the sH type, at 274 K and up to 500 MPa. First, the pure H2 hydrate is investigated in order to determine the upper limit of H 2 content in sH hydrates. It is found that the storage capacity of the hypothetical pure H2 hydrate could reach 3.6 wt % at 500 MPa. Depending on pressure, the large cavity of this hydrate can accommodate up to eight H2 molecules, while the small and medium ones are singly occupied even at pressures as high as 500 MPa. Next, the binary H2-methylcyclohexane sH hydrate is examined. In this case, the small and medium cavities are again singly occupied, resulting in a maximum H2 uptake of 1.4 wt %. Finally, the results from simulations on pure H2 and binary hydrates are utilized to investigate the potential of H2 storage in sH hydrates where the promoter molecules occupy the medium instead of the large cavities.

Evaluation of cotton rats as a model for severe acute respiratory syndrome.

Experimental studies were conducted to evaluate two species of cotton rats, Sigmodon hispidus and Sigmodon fulviventer, as a model for severe acute respiratory syndrome (SARS). Blood and turbinate wash samples, and lung tissue were collected from each animal at different time points after SARS coronavirus (CoV) infection for determining the growth curve of virus, if any, by the standard infectivity assay in Vero E6 cells. In addition, sections of the lung, liver, spleen, and kidney were taken and used for histology analysis. All animals were observed daily for signs of illness, and in some experiments, animals were weighed on the day when they were sacrificed. The results indicated that the cotton rat species, S. hispidus and S. fulviventer, were not a useful model for either SARS-CoV infection or disease. This observation was supported by the absence of any signs of illness, the failure to consistently demonstrate virus in the blood and tissues, and the absent of any notable histopathology. However, infected animals were capable of producing neutralizing antibodies against SARS-CoV, suggesting the seroconversion did occur. Further studies are warranted to consider other animal species in efforts to find better animal models for the evaluation of SARS-CoV vaccines and antiviral drugs.