Added value of spectral computed tomography quantitative parameters for differentiating tuberculosis-associated fibrosing mediastinitis from endobronchial lung cancer: initial results

OBJECTIVE

The objective of this study was to explore the added value of spectral computed tomography (CT) parameters to conventional CT features for differentiating tuberculosis-associated fibrosing mediastinitis (TB-associated FM) from endobronchial lung cancer (EBLC).

METHODS

Chest spectral CT enhancement images from 109 patients with atelectasis were analyzed retrospectively. These patients were divided into two distinct categories: the TB-associated FM group (n = 77) and the EBLC group (n = 32), based on bronchoscopy and/or pathological findings. The selection of spectrum parameters was optimized with the least absolute shrinkage and selection operator regression analysis. The relationship between the spectrum parameters and conventional parameters was explored using Pearson's correlation. Multivariate logistic regression analysis was used to build spectrum model. The spectrum parameters in the spectrum model were replaced with their corresponding conventional parameters to build the conventional model. Diagnostic performances were evaluated using receiver operating characteristic curve analyses.

RESULTS

There was a moderate correlation between the parameters ㏒(L-AEFNIC) - ㏒(L-AEFC) (r= 0.419; p< 0.0001), ㏒(O-AEF40KeV) - ㏒(O-AEFC) (r= 0.475; p< 0.0001), [L-A-hydroxyapatite {HAP}(I)] - (L-U-CT) (r= 0.604; p< 0.0001), {arterial enhancement fraction (AEF) derived from normalized iodine concentration (NIC) of lymph node (L-AEFNIC), AEF derived from CT40KeV of bronchial obstruction (O-AEF40KeV), arterial-phase Hydroxyapatite (Iodine) concentration of lymph node [L-A-HAP(I)], AEF derived from conventional CT (AEFC), unenhanced CT value (U-CT)}. Spectrum model could improve diagnostic performances compared to conventional model (area under curve: 0.965 vs 0.916, p= 0.038).

CONCLUSION

There was a moderate correlation between spectrum parameters and conventional parameters. Integrating conventional CT features with spectrum parameters could further improve the ability in differentiating TB-associated FM from EBLC.

The pig intestinal phageome is an important reservoir and transfer vector for virulence genes

Bacteriophages (phages) can significantly influence the composition and functions of their host communities, and enhance host pathogenicity via the transport of phage-encoded virulence genes. Phages are the main component of animal gut viruses, however, there are few reports on the piglet gut phageome and its contribution to virulence genes. Here, a total of 185 virulence genes from 59,955 predicted genes of gut phages in weaned piglets were identified, with 0.688 % of the phage contigs coding for at least one virulence gene. The virulence gene pblA was the most abundant, with various virulence genes significantly correlated with gut phages and their encoded mobile gene element (MGE) genes. Importantly, multiple virulence genes and MGE genes coexist in some phage sequences, and up to 12 virulence genes were detected in a single phage sequence, greatly increasing the risk of phage-mediated transmission of virulence genes into the bacterial genome. In addition, diarrhoea has driven changes in the composition and structure of phage and bacterial communities in the intestinal tract of weaned piglets, significantly increasing the abundance of phage contigs encoding both virulence genes and MGE genes in faecal samples, which potentially increases the risk of phage-mediated virulence genes being transfected into the gut bacterial genome. In summary, this study expands our understanding of the gut microbiome of piglets, advances our understanding of the potential role of phages in driving host pathogenesis in the gut system, and provides new insights into the sources of virulence genes and genetic evolution of bacteria in pig farm environments.

Aerococcus viridans Phage Lysin AVPL Had Lytic Activity against Streptococcus suis in a Mouse Bacteremia Model

Streptococcus suis (S. suis) is a swine pathogen that can cause sepsis, meningitis, endocarditis, and other infectious diseases; it is also a zoonotic pathogen that has caused a global surge in fatal human infections. The widespread prevalence of multidrug-resistant S. suis strains and the decline in novel antibiotic candidates have necessitated the development of alternative antimicrobial agents. In this study, AVPL, the Aerococcus viridans (A. viridans) phage lysin, was found to exhibit efficient bactericidal activity and broad lytic activity against multiple serotypes of S. suis. A final concentration of 300 μg/mL AVPL reduced S. suis counts by 4-4.5 log10 within 1 h in vitro. Importantly, AVPL effectively inhibited 48 h S. suis biofilm formation and disrupted preformed biofilms. In a mouse model, 300 μg/mouse AVPL protected 100% of mice from infection following the administration of lethal doses of multidrug-resistant S. suis type 2 (SS2) strain SC19, reduced the bacterial load in different organs, and effectively alleviated inflammation and histopathological damage in infected mice. These data suggest that AVPL is a valuable candidate antimicrobial agent for treating S. suis infections.

Correlation of pericoronary adipose tissue CT attenuation values of plaques and periplaques with plaque characteristics

AIM

To investigate the relationship between different plaque characteristics and pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation values for plaques and periplaques.

MATERIALS AND METHODS

The data from 188 eligible patients with stable coronary heart disease (280 lesions) who underwent coronary CT angiography between March 2021 and November 2021 were collected retrospectively. All PCAT CT attenuation values of plaques and periplaques (the area within 5 and 10 mm proximal and distal to the plaque) were calculated, and multiple linear regression was used to assess their correlation with different plaque characteristics.

RESULTS

PCAT CT attenuation of plaques and periplaques was higher in non-calcified plaques (-73.38 ± 10.41 HU, -76.77 ± 10.86 HU, 79.33 ± 11.13 HU, -75.67 ± 11.24 HU, -78.63 ± 12.09 HU) and mixed plaques (-76.83 ± 8.11 HU, -79 [-85, -68.5] HU, -78.55 ± 11 HU, -78.76 ± 9.9 HU, -78.79 ± 11.06 HU) than in calcified plaques (-86.96 ± 10 HU, -84 [-92, -76] HU, -84.14 ± 11.08 HU, -84.91 ± 11.41 HU, -84.59 ± 11.69 HU; all p<0.05) and higher in distal segment plaques than in proximal segment plaques (all p<0.05). Plaque PCAT CT attenuation was lower in plaques with minimal stenosis than in plaques with mild or moderate stenosis (p<0.05). The significant determinants of PCAT CT attenuation values of plaques and periplaques were non-calcified plaques, mixed plaques, and plaques located in the distal segment (all p<0.05).

CONCLUSIONS

PCAT CT attenuation values in both plaques and periplaques were related to plaque type and location.

[Establishment and validation of a nomogram for predicting prognosis of gastric neuroendocrine neoplasms based on data from 490 cases in a single center]

OBJECTIVE

To develop and validate a nomogram for predicting outcomes of patients with gastric neuroendocrine neoplasms (G-NENs).

METHODS

We retrospectively collected the clinical data from 490 patients with the diagnosis of G-NEN at our medical center from 2000 to 2021. Log-rank test was used to analyze the overall survival (OS) of the patients. The independent risk factors affecting the prognosis of G-NEN were identified by Cox regression analysis to construct the prognostic nomogram, whose performance was evaluated using the C-index, receiver-operating characteristic (ROC) curve, area under the ROC curve (AUC), calibration curve, DCA, and AUDC.

RESULTS

Among the 490 G-NEN patients (mean age of 58.6±10.92 years, including 346 male and 144 female patients), 130 (26.5%) had NET G1, 54 (11.0%) had NET G2, 206 (42.0%) had NEC, and 100 (20.5%) had MiNEN. None of the patients had NET G3. The numbers of patients in stage Ⅰ-Ⅳ were 222 (45.3%), 75 (15.3%), 130 (26.5%), and 63 (12.9%), respectively. Univariate and multivariate analyses identified age, pathological grade, tumor location, depth of invasion, lymph node metastasis, distant metastasis, and F-NLR as independent risk factors affecting the survival of the patients (P < 0.05). The C-index of the prognostic nomogram was 0.829 (95% CI: 0.800-0.858), and its AUC for predicting 1-, 3- and 5-year OS were 0.883, 0.895 and 0.944, respectively. The calibration curve confirmed a good consistency between the model prediction results and the actual observations. For predicting 1-year, 3-year and 5-year OS, the TNM staging system and the nomogram had AUC of 0.033 vs 0.0218, 0.191 vs 0.148, and 0.248 vs 0.197, respectively, suggesting higher net benefit and better clinical utility of the nomogram.

CONCLUSION

The prognostic nomogram established in this study has good predictive performance and clinical value to facilitate prognostic evaluation of individual patients with G-NEN.

Metagenomics analysis reveals potential pathways and drivers of piglet gut phage-mediated transfer of ARGs

The growing prevalence of antibiotic-resistant pathogens has led to a better understanding of the underlying processes that lead to this expansion. Intensive pig farms are considered one of the hotspots for antibiotic resistance gene (ARG) transmission. Phages, as important mobile carriers of ARGs, are widespread in the animal intestine. However, our understanding of phage-associated ARGs in the pig intestine and their underlying drivers is limited. Here, metagenomic sequencing and analysis of viral DNA and total DNA of different intestinal (ileum, cecum and feces) contents in healthy piglets and piglets with diarrhea were separately conducted. We found that phages in piglet ceca are the main repository for ARGs and mobile genetic element (MGE) genes. Phage-associated MGEs are important factors affecting the maintenance and transfer of ARGs. Interestingly, the colocalization of ARGs and MGE genes in piglet gut phages does not appear to be randomly selected but rather related to a specific phage host (Streptococcus). In addition, in the feces of piglets with diarrhea, the abundance of phages carrying ARGs and MGE genes was significantly increased, as was the diversity of polyvalent phages (phages with broad host ranges), which would facilitate the transfection and wider distribution of ARGs in the bacterial community. Moreover, the predicted host spectrum of polyvalent phages in diarrheal feces tended to be potential enteropathogenic genera, which greatly increased the risk of enteropathogens acquiring ARGs. Notably, we also found ARG-homologous genes in the sequences of piglet intestinal mimiviruses, suggesting that the piglet intestinal mimiviruses are a potential repository of ARGs. In conclusion, this study greatly expands our knowledge of the piglet gut microbiome, revealing the underlying mechanisms of maintenance and dissemination of piglet gut ARGs and providing a reference for the prevention and control of ARG pollution in animal husbandry.

A phage cocktail combined with the enteric probiotic Lactobacillus reuteri ameliorated mouse colitis caused by S. typhimurium

Salmonella enterica serovar Typhimurium (S. typhimurium) is one of the most important foodborne pathogens that causes colitis in humans. In this study, we compared the effects of a therapeutic treatment using a phage cocktail (Pc) in combination or not with Lactobacillus reuteri (L. reuteri) in an S. typhimurium-induced colitis murine model. An oral administration of 4 × 10⁸ CFU per mouse of S. typhimurium resulted in intestinal barrier disruption and severe inflammatory symptoms. S. typhimurium in the colon of the mice treated with the Pc and L. reuteri (PcLR) combination were completely removed compared to those in the single Pc or single L. reuteri treatment groups. Furthermore, compared with the infected group, the intestinal barrier and colonic pathological damage were significantly improved in the PcLR-treated group. Additionally, the short-chain fatty acid (SCFA) levels in the feces of the mice in the PcLR treatment group were significantly increased compared to those in the feces of the mice in the infected group. In addition, the combination of Pc with acetate and reuterin released by L. reuteri (PcReAc) can also achieve the same effect as PcLR treatment. Thus, these results indicated that the acetate and reuterin released by L. reuteri play an important role in the treatment. The extraordinary therapeutic effects of PcLR and PcReAc depend on the specific bactericidal activity of Pc and the broad-spectrum bactericidal activity and immunomodulation of L. reuteri (or acetate and reuterin) in the host. This study provides a new concept for the treatment of inflammatory diseases caused by intestinal pathogens.

The Combination of Phages and Faecal Microbiota Transplantation Can Effectively Treat Mouse Colitis Caused by Salmonella enterica Serovar Typhimurium

Salmonella enterica serovar Typhimurium (S. Typhimurium) is one of the common causes of human colitis. In the present study, two lytic phages vB_SenS-EnJE1 and vB_SenS-EnJE6 were isolated and the therapeutic effect of the combination of phages and faecal microbiota transplantation (FMT) on S. Typhimurium-induced mouse colitis was investigated. The characteristics and genome analysis indicated that they are suitable phages for phage therapy. Results showed that vB_SenS-EnJE1 lysis 41/54 Salmonella strains of serotype O4, and vB_SenS-EnJE6 lysis 46/54 Salmonella strains of serotypes O4 and O9. Severe inflammatory symptoms and disruption of the intestinal barrier were observed in S. Typhimurium -induced colitis. Interestingly, compared with a single phage cocktail (Pc) or single FMT, the combination of Pc and FMT (PcFMT) completely removed S. Typhimurium after 72 h of treatment, and significantly improved pathological damage and restored the intestinal barrier. Furthermore, PcFMT effectively restored the intestinal microbial diversity, especially for Firmicutes/Bacteroidetes [predominantly bacterial phyla responsible for the production of short-chain fatty acids (SCFA)]. Additionally, we found that PcFMT treatment significantly increased the levels of SCFA. All these data indicated that the combination of phages and FMT possesses excellent therapeutic effects on S. Typhimurium -induced intestinal microbiota disorder diseases. Pc and FMT played roles in “eliminating pathogens” and “strengthening vital qi,” respectively. This study provides a new idea for the treatment of intestinal microbiota disorder diseases caused by specific bacterial infections.

Oral vaccination with recombinant Lactobacillus casei expressing Aha1 fused with CTB as an adjuvant against Aeromonas veronii in common carp (Cyprinus carpio)

Aeromonas veronii (A. veronii) is a pathogenic that can infect human, animal and aquatic organisms, in which poses a huge threat to the health of many aquatic organisms such as Cyprinus carpio. In this study, Lactobacillus casei (L. casei) strain CC16 was used as antigen deliver carrier and fused with cholera toxin B subunit (CTB) as an adjuvant to construct the recombinant L. casei pPG-Aha1/Lc CC16(surface-displayed) and pPG-Aha1-CTB/Lc CC16(surface-displayed) expressing Aha1 protein of A. veronii, respectively. And the immune responses in Cyprinus carpio by oral route was explored. Our results demonstrated that the recombinant strains could stimulate high serum specific antibody immunoglobulin M (IgM) and induce a stronger acid phosphatase (ACP), alkaline phosphatase (AKP), C3, C4, lysozyme (LZM), Lectin and superoxide dismutase (SOD) activity in Cyprinus carpio compared with control groups. Meanwhile, the expression of Interleukin-10 (IL-10), Interleukin-1β (IL-1β), Tumor Necrosis Factor-α (TNF-α), immunoglobulin Z1 (IgZ1) and immunoglobulin Z2 (IgZ2) in the tissues were significantly upregulated compared with Lc-pPG or PBS groups, indicating that humoral and cell immune response were triggered. Additionally, recombinant L. casei could survive and colonize in fish intestine. Significantly, recombinant L. casei provides immune protection against A. veronii infection, which Cyprinus carpio received pPG-Aha1-CTB/Lc CC16 (64.29%) and pPG-Aha1/Lc CC16 (53.57%) had higher survival rates compared with the controls. Thus, we demonstrated that recombinant pPG-Aha1/Lc CC16 and pPG-Aha1-CTB/Lc CC16 may be the promising strategy for the development of an oral vaccine against A. veronii.

The Bacteriophage vB_CbrM_HP1 Protects Crucian Carp Against Citrobacter braakii Infection

Citrobacter braakii is an opportunistic pathogen that induces aquatic infections in fish and turtles. In this study, a bacteriophage that infects C. braakii, named vB_CbrM_HP1, was isolated from sewage. This phage belongs to Myoviridae family, Ounavirinae subfamily, Mooglevirus genus. We also used the phage to treat crucian carp infection caused by C. braakii for the first time. vB_CbrM_HP1 was relatively stable at temperatures ranging from 4 to 60°C and pH values ranging from 3 to 11 but float slightly. When the multiplicities of infection (MOI) was 0.0001, the titer reached a maximum of 4.20 × 1010 PFU/ml. As revealed from the results of whole genomic sequence analysis, the total length of vB_CbrM_HP1 was 89335 bp, encoding 135 ORFs, 9 of which were &lt;75% similar to the known sequences in NCBI. The phage vB_CbrM_HP1 showed a highly efficient bactericidal effect against C. braakii both in vitro and in vivo. In vitro, vB_CbrM_HP1 was capable of effectively killing bacteria (the colony count decreased by 4.7 log units at 5 h). In vivo, administration of vB_CbrM_HP1 (1 × 109 PFU) effectively protected crucian carp against fatal infection caused by C. braakii. Phage treatment reduced the levels of inflammatory factors. All these results demonstrated the potential of vB_CbrM_HP1 as an alternative treatment strategy for infections caused by C. braakii.

P–138 When is low quality really low? Should we transfer low-grade blastocysts?

Study question

What is the live birth rate after single, low-grade blastocyst (LGB) transfer?

Summary answer

The live birth rate for LGBs is 28%, ranging between 15–31% for the different inner cell mass (ICM) and trophectoderm (TE) subgroups of LGBs.

What is known already

Live birth rates following LGB transfer are varied and have been reported to be in the range of 5–39%. However, these estimates are inaccurate as studies investigating live birth rates following LGB transfer are inherently limited by sample size (n = 10–440 for LGB transfers) due to LGBs being ranked last for transfer. Further, these studies are heterogenous with varied LGB definitions and design. Collating LGB live birth data from multiple clinics is warranted to obtain sufficient numbers of LGB transfers to establish reliable live birth rates, and to allow for delineation of different LGB subgroups, including blastocyst age and female age.

Study design, size, duration

We performed a multicentre, multinational retrospective cohort study in 9 IVF centres in China and New Zealand from 2012 to 2019. We studied the outcome of 6966 single blastocyst transfer cycles on days 5–7 (fresh and frozen) according to blastocyst grade, including 875 transfers from LGBs (&lt;3bb, this being the threshold typically applied to LGB studies). Blastocysts with expansion stage 1 or 2 (early blastocysts) were excluded.

Participants/materials, setting, methods

The main outcome measured was live birth rate. Blastocysts were grouped according to quality grade: good-grade blastocysts (GGBs; n = 3849, aa, ab and ba), moderate-grade blastocysts (MGBs; n = 2242, bb) and LGBs (n = 875, ac, ca, bc, cb and cc) and live birth rates compared using the Pearson Chi-squared test. A logistic regression analysis explored the relationship between blastocyst grade and live birth after adjustment for the confounders: clinic, female age, expansion stage, and blastocyst age.

Main results and the role of chance

The live birth rates for GGBs, MGBs and LGBs were 45%, 36% and 28% respectively (p &lt; 0.0001). Within the LGB group, the highest live birth rates were for grade c TE (30%) and the lowest were for grade c ICM (19%). The lowest combined grade (cc) maintained a 15% live birth rate (n = 7/48). After accounting for confounding factors, including female age and blastocyst characteristics, the odds of live birth were 2.33 (95% CI = 1.88–2.89) for GGBs compared to LGBs and 1.56 (95% CI = 1.28–1.92) for MGBs compared to LGBs following fresh and frozen blastocyst transfers (p &lt; 0.0001, odds ratios confirmed in exclusively frozen blastocyst transfer cycles). When stratified by individual ICM and TE grade, the odds of live birth according to ICM grade were 1.31 (a versus b; 95% CI = 1.15–1.48), 2.82 (a versus c; 95% CI = 1.91–4.18) and 2.16 (b versus c; 95% CI = 1.48–3.16; all p &lt; 0.0001). The odds of live birth according to TE grade were 1.33 (a versus b; 95% CI = 1.17–1.50, p &lt; 0.0001), 1.85 (a versus c; 95% CI = 1.45–2.34, p &lt; 0.0001) and 1.39 (b versus c; 95% CI = 1.12–1.73, p = 0.0024).

Limitations, reasons for caution

Despite the large multicentre design of the study, analyses of transfers occurring within the smallest subsets of the LGB group were limited by sample size. The study was not randomised and had a retrospective character.

Wider implications of the findings: LGBs maintain satisfactory live birth rates (averaging 28%) in the general IVF population. Even those in the lowest grading tier maintain modest live birth rates (15%; cc). It is recommended that LGBs not be universally discarded, and instead considered for subsequent frozen embryo transfer to maximize cumulative live birth rates.

Trial registration number

Not applicable

[Holistic view of surgery based on membrane anatomy for gastrointestinal tumor]

The mesentery is a continuous unity and the operation of digestive carcinoma is the process of mesenteric resection. This paper attempts to simplify the formation process of all kinds of fusion fascia in the process of digestive tract embryogenesis, and to illuminate the continuity of fusion fascia with a holistic concept. This is helpful for beginners to reversely dissect the fusion fascia and maintain the correct surgical plane during operation, and to achieve the purpose of complete mesenteric resection.

Combination Therapy of Phage vB_KpnM_P-KP2 and Gentamicin Combats Acute Pneumonia Caused by K47 Serotype Klebsiella pneumoniae

Klebsiella pneumoniae (K. pneumoniae) is an important nosocomial and community acquired opportunistic pathogen which causes various infections. The emergence of multi-drug resistant (MDR) K. pneumoniae and carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) has brought more severe challenge to the treatment of K. pneumoniae infection. In this study, a novel bacteriophage that specifically infects K. pneumoniae was isolated and named as vB_KpnM_P-KP2 (abbreviated as P-KP2). The biological characteristics of P-KP2 and the bioinformatics of its genome were analyzed, and then the therapeutic effect of P-KP2 was tested by animal experiments. P-KP2 presents high lysis efficiency in vitro. The genome of P-KP2 shows homology with nine phages which belong to “KP15 virus” family and its genome comprises 172,138 bp and 264 ORFs. Besides, P-KP2 was comparable to gentamicin in the treatment of lethal pneumonia caused by K. pneumoniae W-KP2 (K47 serotype). Furthermore, the combined treatment of P-KP2 and gentamicin completely rescued the infected mice. Therefore, this study not only introduces a new member to the phage therapeutic library, but also serves as a reference for other phage-antibiotic combinations to combat MDR pathogens.

Bacteriophage Protects Against Aerococcus viridans Infection in a Murine Mastitis Model

Bovine mastitis, an inflammatory disease that occurs frequently in early lactation or the dry period, is primarily caused by bacterial infections. There is growing evidence that Aerococcus viridans (A. viridans) is becoming an important cause of bovine mastitis. The treatment of bovine mastitis is primarily based on antibiotics, which not only leads to a large economic burden but also the development of antibiotic resistance. On the other hand, bacteriophages present a promising alternative treatment strategy. The object of this study was to evaluate the potential of a previously isolated A. viridans phage vB_AviM_AVP (AVP) as an anti-mastitis agent in an experimental A. viridans-induced murine mastitis model. A. viridans N14 was isolated from the milk of clinical bovine mastitis and used to establish a mastitis model in mice. We demonstrated that administration of phage AVP significantly reduced colony formation by A. viridans and alleviated damage to breast tissue. In addition, reduced inflammation was indicated by decreased levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) and myeloperoxidase (MPO) activity in the phage-treated group compared to those in the phosphate buffered saline (PBS)-treated group. To the best of our knowledge, this report is the first to show the potential use of phages as a treatment for A. viridans-induced mastitis.

The characteristics and genome analysis of vB_ApiP_XC38, a novel phage infecting Acinetobacter pittii

Acinetobacter pittii is an important pathogen causing nosocomial infection worldwide. In this study, a multidrug-resistant A. pittii ABC38 was used as host bacterium to isolate the lytic phage vB_ApiP_XC38. The biological characteristics of vB_ApiP_XC38 were studied and the genome was sequenced and analyzed. vB_ApiP_XC38 belonged to Podoviridae family. The phage had double-stranded genome, which comprised 79,328 bp with 39.58% G+C content displaying very low similarity (< 1% identity) with published genomes of other phages and bacteria. A total of 97 open reading frames (ORFs) were predicted and contained nucleotide metabolism and replication module, structural components module, and lysis module. The ANI, AAI, and phylogenetic analysis indicated that all phages were found distant from vB_ApiP_XC38. Altogether, morphological, genomics, and phylogenetic analysis suggest that vB_ApiP_XC38 is more likely a novel phage of A. pittii.

The characteristics and genome analysis of the novel Y. pestis phage JC221

The pathogen of plague is Yersinia pestis (Y. pestis), one of the deadliest pathogens in the world and belonging to the family Enterobacteriaceae. In this work, the biological characteristics and complete genome sequence analysis of a novel lytic Y. pestis-specific phage JC221 isolated from Yunnan Province, China, was studied. JC221 belongs to the Myoviridae family and has a regular icosahedral head and a long contractile tail. The double-stranded DNA genome of JC221 contains 174,931 bp, and the G + C content is 41.23 %. There are 274 predicted genes, of which only 103 hits of genes or gene products are found in database searches, and there are no known virulence-related or antibiotic resistance genes. The genome sequence of JC221 showed <80 % identity to other phages, and evolutionary analysis revealed that bacteriophage JC221 belongs to the Yersinia phage cluster. Furthermore, the bacteriophage could completely lyse most of the tested Y. pestis strains (12/13) at 28 °C and 37 °C, and some Shigella strains could be lysed at 37°C. Morphological and genomic analysis indicated that JC221 is a new Y. pestis phage and a new member of the Tequatrovirus phages. The novel Y. pestis phage JC221 has important reference value for the study of environmental microecology and epidemiology of plague foci.

The Yersinia Phage X1 Administered Orally Efficiently Protects a Murine Chronic Enteritis Model Against Yersinia enterocolitica Infection

Yersinia enterocolitica is generally considered an important food-borne pathogen worldwide, especially in the European Union. A lytic Yersinia phage X1 (Viruses; dsDNA viruses, no RNA stage; Caudovirales; and Myoviridae) was isolated. Phage X1 showed a broad host range and could effectively lyse 27/51 Y. enterocolitica strains covering various serotypes that cause yersiniosis in humans and animals (such as serotype O3 and serotype O8). The genome of this phage was sequenced and analyzed. No toxin, antibiotic-resistance or lysogeny related modules were found in the genome of phage X1. Studies of phage stability confirmed that X1 had a high tolerance toward a broad range of temperatures (4–60°C) and pH values (4–11) for 1 h. The ability to resist harsh acidic conditions and enzymatic degradation in vitro demonstrated that phage X1 is suitable for oral administration, and in particular, that this phage can pass the stomach barrier and efficiently reach the intestine in vivo without losing infectious ability. The potential of this phage against Y. enterocolitica infection in vitro was studied. In animal experiments, a single oral administration of phage X1 at 6 h post infection was sufficient to eliminate Y. enterocolitica in 33.3% of mice (15/45). In addition, the number of Y. enterocolitica strains in the mice was also dramatically reduced to approximately 10³ CFU/g after 18 h compared with 10⁷ CFU/g in the mice without phage treatment. Treatment with phage X1 showed significant improvement by intestinal histopathologic observations. Moreover, proinflammatory cytokine levels (IL-6, TNF-α, and IL-1β) were significantly reduced (P < 0.05). These results indicate that phage X1 is a promising candidate to control infection by Y. enterocolitica in vivo.

Long-term decomposed straw return positively affects the soil microbial community

AIMS

In order to understand the response of soil microbial communities to the long-term of decomposed straw return, the modifications of soil microbial community structure and composition induced by more than 10 years of fresh and decomposed straw return was investigated and the key environmental factors were analysed.

METHODS AND RESULTS

Phospholipid fatty acid analysis and high-through sequencing technique were applied to analyse the structure and composition of the soil microbial communities. Compared with fresh straw, returning decomposed straw increased the relative abundance of bacteria and fungi by 1·9 and 7·7% at a rate of ~3750 kg ha^-1 , and increased by 23·1 and 5·7%, at a rate of ~7500 kg ha^-1 respectively. The relative abundance of the bacteria related to soil nitrification increased, but the ones related to soil denitrification decreased with decomposed straw return, which led to higher total nitrogen contents in soils. Moreover, returning decomposed straw reduced pathogenic fungal populations (genus of Alternara), which had significantly positive correlation with soil electric conductivity. It indicated that the long-term of decomposed straw return might have lower risk of soil-borne disease mainly for the reasonable soil salinity.

CONCLUSIONS

Long-term of decomposed straw return could provide suitable nutrient and salinity for healthier development of soil microbial community, both in abundance and structure, compared with fresh straw return.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of the study helps to better understand how the microbial community modifications induced by decomposed straw return benefit on soil health. The obtained key factors impacting soil microbial community variations is meaningful in soil health management under conditions of straw return.

Biological properties and genomics analysis of vB_KpnS_GH-K3, a Klebsiella phage with a putative depolymerase-like protein

Bacteriophages have been recently revisited as an alternative biocontrol tool due to the limitations of antibiotic treatment. In this study, we reported on the biological characteristics and genomic information of vB_KpnS_GH-K3 (abbreviated as GH-K3), a Klebsiella phage of the Siphoviridae family, which was previously isolated from a hospital sewage system. One-step growth curve analysis indicated that the burst size of GH-K3 was 291 PFU/cell. GH-K3 maintained a stable titer in a broad range of pH values (6-10) and temperature (up to 50 °C). Based on bioinformatics analysis, GH-K3 comprises of 49,427 bp containing a total of 77 open reading frames (ORFs), which share high degree of nucleotide similarity and close evolutionary relationships with at least 12 other Klebsiella phages. Of note, GH-K3 gp32 was identified as a unique ORF. The major segment of gp32 sequence at the C-terminus (residues 351-907) was found highly variable as determined by its mismatch with the nucleotide and protein sequences available at NCBI database. Furthermore, HHpred analysis indicated that GH-K3 gp32 contains three domains (PDB ID: 5W6S_A, 3GQ8_A and 1BHE_A) similar to depolymerase (depoKP36) of Klebsiella phage KP36 suggestive of a potential depolymerase activity during host receptor-binding in the processes of phage infection. Altogether, the current data revealed a novel putative depolymerase-like protein which is most likely to play an important role in phage-host interaction.

Three Capsular Polysaccharide Synthesis-Related Glucosyltransferases, GT-1, GT-2 and WcaJ, Are Associated With Virulence and Phage Sensitivity of Klebsiella pneumoniae

Klebsiella pneumoniae (K. pneumoniae) spp. are important nosocomial and community-acquired opportunistic pathogens, which cause various infections. We observed that K. pneumoniae strain K7 abruptly mutates to rough-type phage-resistant phenotype upon treatment with phage GH-K3. In the present study, the rough-type phage-resistant mutant named K7R^R showed much lower virulence than K7. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) analysis indicated that WcaJ and two undefined glycosyltransferases (GTs)- named GT-1, GT-2- were found to be down-regulated drastically in K7R^R as compared to K7 strain. GT-1, GT-2, and wcaJ are all located in the gene cluster of capsular polysaccharide (CPS). Upon deletion, even of single component, of GT-1, GT-2, and wcaJ resulted clearly in significant decline of CPS synthesis with concomitant development of GH-K3 resistance and decline of virulence of K. pneumoniae, indicating that all these three GTs are more likely involved in maintenance of phage sensitivity and bacterial virulence. Additionally, K7R^R and GT-deficient strains were found sensitive to endocytosis of macrophages. Mitogen-activated protein kinase (MAPK) signaling pathway of macrophages was significantly activated by K7R^R and GT-deficient strains comparing with that of K7. Interestingly, in the presence of macromolecular CPS residues (>250 KD), K7(ΔGT-1) and K7(ΔwcaJ) could still be bounded by GH-K3, though with a modest adsorption efficiency, and showed minor virulence, suggesting that the CPS residues accumulated upon deletion of GT-1 or wcaJ did retain phage binding sites as well maintain mild virulence. In brief, our study defines, for the first time, the potential roles of GT-1, GT-2, and WcaJ in K. pneumoniae in bacterial virulence and generation of rough-type mutation under the pressure of bacteriophage.

Preventive effect of the phage VB-SavM-JYL01 on rabbit necrotizing pneumonia caused by Staphylococcus aureus

Staphylococcus aureus is one of the most important pathogens causing rabbit necrotizing pneumonia and brings huge economic losses to rabbit production. This study investigated the preventive effect of a phage on rabbit necrotizing pneumonia caused by S. aureus. S. aureus S6 was isolated from the lungs of rabbits suffering necrotizing pneumonia and identified. A novel phage named VB-SavM-JYL01 was isolated by using S. aureus S6 as a host and showed a broader host range than the phages GH15 and K. The genome of VB-SavM-JYL01 lacked bacterial virulence-, antibiotic resistance- and lysogenesis-related genes. A single intranasal administration of VB-SavM-JYL01 (3 × 10⁹ PFU) could effectively improve the survival rate at 48 h to 90% (9/10) compared with the survival rate of 10% and 80% observed with the PBS or linezolid treatment, respectively. The bacterial count in the lungs of rabbits treated with the phage VB-SavM-JYL01 was 4.18 × 10⁴ CFU/g at 24 h, which was significantly decreased compared to that of rabbits treated with PBS (7.38 × 10⁷ CFU/g) or linezolid (3.12 × 10⁵ CFU/g). The phage treatment significantly alleviated lung tissue damage. The levels of total proteins, Panton-Valentine leukocidin (PVL), alpha-toxin (Hla) and cytokines in the lungs of the rabbits treated with the phage were significantly lower than those of the rabbits treated with PBS and similar to those of the rabbits treated with linezolid. These data demonstrate the potential utility of phage as an alternative for preventing rabbit necrotizing pneumonia caused by S. aureus.

A Smooth-Type, Phage-Resistant Klebsiella pneumoniae Mutant Strain Reveals that OmpC Is Indispensable for Infection by Phage GH-K3

Bacteriophage can be used as an alternative or complementary therapy to antibiotics for treating multidrug-resistant bacterial infections. However, the rapid emergence of resistant host variants during phage treatment has limited its therapeutic applications. In this study, a potential phage-resistant mechanism of Klebsiella pneumoniae was revealed. After phage GH-K3 treatment, a smooth-type colony, named K7RB, was obtained from the K. pneumoniae K7 culture. Treatment with IO4- and/or proteinase K indicated that polysaccharides of K7 played an important role in phage recruitment, and protein receptors on K7 were essential for effective infection by GH-K3. Differences in protein expression between K7 and K7RB were quantitatively analyzed by liquid chromatography-tandem mass spectrometry. Among differentially expressed proteins, OmpC, OmpN, KPN_02430, and OmpF were downregulated significantly in K7RBtrans-Complementation of OmpC in K7RB conferred rapid adsorption and sensitivity to GH-K3. In contrast, a single-base deletion mutation of ompC in K7, which resulted in OmpC silencing, led to lower adsorption efficiency and resistance to GH-K3. These assays proved that OmpC is the key receptor-binding protein for GH-K3. In addition, the native K. pneumoniae strains KPP14, KPP27, and KPP36 showed low or no sensitivity to GH-K3. However, these strains became more sensitive to GH-K3 after their native receptors were replaced by OmpC of K7, suggesting that OmpCK7 was the most suitable receptor for GH-K3. This study revealed that K7RB became resistant to GH-K3 due to gene mutation of ompC and that OmpC of K7 is essential for effective infection by GH-K3.IMPORTANCE With increased incidence of multidrug-resistant (MDR) bacterial strains, phages have regained attention as promising potential antibacterial agents. However, the rapid emergence of resistant variants during phage treatment has limited the therapeutic applications of phage. According to our trans-complementation, ompC mutation, and phage adsorption efficiency assays, we identified OmpC as the key receptor-binding protein (RBP) for phage GH-K3, which is essential for effective infection. This study revealed that the phage secondary receptor of K. pneumoniae, OmpC, is the essential RBP not only for phage infecting Gram-negative bacteria, such as Escherichia coli and Salmonella, but also for K. pneumoniae.

Effect of local scrotal heating on the expression of tight junction-associated molecule Occludin in boar testes

The aim of this study was to determine whether local scrotal heating (42°C, for 1 hr) had an effect on the expression of tight junction (TJ)-associated molecule Occludin in boar testes. Adult boars (Landrace, n = 6) were used and randomly divided into two groups (n = 3 each). Three boars were given local scrotal exposure to 42°C for approximately 1 h with a home-made electric blanket of controlled temperature as local scrotal heating group, the other three boars received no heat treatment and were left at standard room temperature as control group. After 6 hr, all boars were castrated and the testes were harvested. qRT-PCR, Western blotting and immunohistochemistry were used to explore the expression and localization of Occludin. qRT-PCR and Western blotting showed that the protein and mRNA levels of Occludin significantly decreased in local scrotal heating group as compared to the control. Furthermore, immunoreactivity staining of Occludin was localized at the sites of the blood-testis barrier (BTB) and formed an almost consecutive and strong immunoreactivity strand in the control, while Occludin was limited to Sertoli cells (SCs) and no obvious immunoreactivity strand was present in local scrotal heating group. These data indicated that local scrotal heating decreased the expression of TJ-associated molecule Occludin, which may be involved in heat-induced spermatogenesis damage.

[Application of frailty index for comprehensive geriatric assessment in the elderly in China]

OBJECTIVE

To discuss the suitability of frailty index for comprehensive geriatric assessment(FI-CGA)in the elderly in China, and evaluate the application of FI-CGA in China.

METHODS

A comprehensive geriatric assessment was conducted among 118 old adults receiving health examination, and frailty index was calculated. Clinical frailty scale(CFS)was also used to evaluate the frail status of the old adults. The correlation between FI-CGA value and CFS level of the old adults was analyzed.

RESULTS

The mean value of FI-CGA was 0.19 ± 0.07, and the average level of CFS was 3.11 ± 1.46. Women had higher mean value of FI-CGA and higher CFS level than men(FI-CGA= 0.20 ± 0.02 for women, 0.19 ± 0.07 for men; CFS =3.40 ± 0.55 for women, 3.10 ± 1.48 for men), but the differences had no significance(t=0.270, 0.452, P=0.788, 0.652). The FI-CGA value and CFS level increased with age(F=10.437, 5.651, P=0.000, 0.001); and there was a positive correlation between FI-CGA value and CFS level(r=0.615, P=0.000).

CONCLUSION

FI-CGA is an effective model for the quantitative evaluation of the frail status of the elderly, and can be used in the clinical practice of geriatric medicine.

ZnRF3 induces apoptosis of gastric cancer cells by antagonizing Wnt and Hedgehog signaling

AIM

The aim of this paper was to investigate the function an importance of E3-ubiquitin ligase ZnRF3 in the progression of cancer cell growth.

METHODS

A total of 58 patients (44 males and 14 females) were enrolled in the study and their gastric tumors were removed surgically and were staged by the TNM approach. Among these patients, 43 patients died and 15 survived at the time of this study. The tumors and the paracancerous tissues were examined by immunohostochemistry for the expression of ZnRF3. We assessed the expression of ZnRF3 in gastric tumors and paracancerous tissues from our patients and related this to patient survival.

RESULTS

A large proportion of malignant cancers of the stomach are gastric adenocarcinoma type. In spite of many studies, the molecular basis for this cancer is still unclear. Deregulated cell proliferative signaling via Wnt/β-catenin and Hedgehog pathways is considered important in the pathogenesis of many cancers including the gastric cancer. Recent studies identified ZnRF3 protein, which is a E3-ubiquitin ligase and which is either deleted or mutated in cancers, to inhibit Wnt signaling. However, the significance of ZnRF3 in the control of gastric cancer and whether it also regulates Hedgehog signaling pathway, is not known. ZnRF3 expression was much higher in tumors from aged patients. Male patients showed higher mortality than the females. Mechanistic studies using normal gastric cells (GES1) and gastric cancer cells (MGC-803) infected with either AdZnRF3 or AdGFP viral vectors, revealed that ZnRF3 overexpression causes significantly more apoptosis and lowered proliferation of cancer cells. ZnRF3 overexpression led to greatly reduced levels of Lgr5, a component of Wnt signaling and also Gli1, a component of Hedgehog signaling. Thus, ZnRF3 negatively influences both the Wnt and Hedgehog proliferative pathways and probably this way it negatively regulates cancer progression. These results suggest the importance of normal ZnRF3 function in checking the progression of cancer cell growth and indicate that a lack of this protein can lead to poorer clinical outcomes for gastric cancer patients.

CONCLUSION

We observed a clear relationship between ZnRF3 expression in paracancerous tissue and tumor size.

The Effects of Epidural Anaesthesia and Analgesia on Natural Killer Cell Cytotoxicity and Cytokine Response in Patients with Epithelial Ovarian Cancer Undergoing Radical Resection

Objective:

Epidural anaesthesia appears to promote antitumourigenic activity in patients with malignant disease who are undergoing surgery. This study investigated immune function in women with epithelial ovarian cancer undergoing radical resection with either general anaesthesia alone or in combination with epidural anaesthesia.

Methods:

Patients ( n = 61) were randomized to receive either combined general/epidural anaesthesia (study group) or general anaesthesia alone (control group). Natural killer cell cytotoxicity (NKCC) and serum concentrations of four cytokines (interleukin [IL]-1β, -8 and -10 and interferon [IFN]-γ) were measured before anaesthesia ( Tpre) and 4h after skinincision ( T4 h) in both groups.

Results:

In both groups, concentrations of protumourigenic cytokines (IL-1β and IL-8) were significantly higher at T4 h than at Tpre, while concentrations of antitumourigenic cytokines (IL-10 and IFN-γ) and NKCC were significantly lower at T4 h. The study group had significantly higher NKCC, IL-10 and IFN-γ levels and lower IL-1β and IL-8 levels at TT h compared with the control group.

Conclusion:

Combined general/epidural anaesthesia appeared to promote antitumourigenic NKCC and cytokine responses.

Association of COX-2 expression with corresponding active and chronic inflammatory reactions in Barrett's metaplasia and progression to cancer

AIMS

Risk reduction for Barrett's cancer in individuals taking non-steroidal anti-inflammatory drugs has been reported. Cyclooxygenase (COX)-2, one of the inhibited enzymes, is putatively involved in Barrett's cancer pathogenesis. The aim of this study was to examine a possible association between COX-2 protein expression and the development and progression of the Barrett's metaplasia-dysplasia-carcinoma sequence and the type and degree of associated inflammatory reaction.

METHODS AND RESULTS

Squamous epithelium, metaplastic, low-grade, high-grade dysplastic lesions and tumour tissue of 49 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analysed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. Within the Barrett's sequence, a significant progressive increase in COX-2 expression was identified (P < 0.0001). The most significant differences were detected between squamous epithelium and Barrett's metaplasia (P < 0.001) and from low- to high-grade dysplasia (P < 0.0001). Active and chronic inflammation were significantly different between squamous epithelium and Barrett's metaplasia (P < 0.0001), but not during further progression in the sequence.

CONCLUSIONS

Increasing COX-2 expression in Barrett's metaplasia is significantly associated with a change in the local inflammatory reaction, but not during further progression through dysplasia to cancer. This supports the potential of a chemoprevention strategy using COX-2 inhibitors independent of the extent and type of the inflammatory reaction in Barrett's oesophagus.

Patient characteristics and costs associated with dyslipidaemia and related conditions in HIV-infected patients: a retrospective cohort study

BACKGROUND

Metabolic abnormalities are common in HIV-infected individuals and, although multifactorial in origin, have been strongly associated with antiretroviral therapy.

METHODS

Using automated claims and clinical databases, combined with medical record data, we evaluated the burden of dyslipidaemia (DYS) and associated metabolic abnormalities among a cohort of 900 HIV-infected patients aged 18 years and older who received their care from a large multispecialty medical group between 1 January 1996 and 30 June 2002. A Cox proportional hazards model for DYS was developed. Resource use was compiled and subsequently costed with stratification to account for variable length of follow-up.

RESULTS

Mean follow-up time was 3.3 years. DYS was present in 54% of the cohort and 3.4% experienced a cardiovascular (CV) event. Both unadjusted and adjusted results found patients with dyslipidaemia and cardiovascular events significantly more likely to have received protease inhibitor (PI) treatment for longer periods of time. In the Cox proportional hazards model the following factors were significantly associated with an increased risk for DYS: older age, white race, PI use and male sex. Diagnoses of hypertension, hepatitis C virus infection, depression or opportunistic infections were all negatively associated with a DYS diagnosis. When controlled for length of follow up, patients with DYS (and no CV-related events) incurred greater median and mean total average costs than patients without DYS or CV-related events. For patients with more than 2 years of follow up, these total cost differences were statistically significant (P<0.05).

CONCLUSIONS

These findings indicate that DYS is common among patients with HIV infection and is associated with increased use of medical resources.

Recognition of Triple Helical Nucleic Acids by Aminoglycosides

Aminoglycosides, traditional RNA binders, were found to be a new class of triple helical nucleic acid-stabilizing ligands. Neomycin, of all the aminoglycosides, has shown the most significant effects in stabilizing DNA, RNA, and hybrid triple helices. When compared with minor groove binders or intercalators, neomycin excels at triple helical stabilization in most cases. Molecular modeling studies suggest that neomycin reaches into the larger Watson-Hoogsteen groove. The charge and shape complementarity are the key factors in neomycin-triplex recognition. By conjugating neomycin with intercalators such as BQQ (a potent triple helix intercalating agent designed by Hélène), we have progressed in developing more potent triple helix stabilizing ligands. The design of such dual or even triple recognition ligands opens a new paradigm for recognition of triple helix nucleic acids. The article herein presents studies of neomycin as the first molecule that can selectively stabilize nucleic acid triplex structures. These studies are supported by our recent discovery that neomycin prefers to bind to A-like conformations, of which triple helix structures are known to display some characteristics. These findings will contribute to the development of a new series of triplex-specific ligands, and may contribute to either antisense or antigene therapies.

Impaired class II transactivator expression in mice lacking interferon regulatory factor-2

Class II transactivator (CIITA) is required for both constitutive and inducible expression of MHC class II genes. IFN-gamma induced expression of CIITA in various cell types is directed by CIITA type IV promoter. The two transactivators, STAT1 and IRF-1, mediate the IFN-gamma activation of the type IV promoter by binding to the GAS and IRF-E of the promoter, respectively. In addition to IRF-1, IRF-2, another member of the IRF family, also activates the human CIITA type IV promoter, and IRF-2 cooperates with IRF-1 to activate the promoter in transient transfection assays. IRF-1 and IRF-2 can co-occupy the IRF-E of the human CIITA type IV promoter. To understand the effect of loss of IRF-2 on the endogenous CIITA expression, we assayed for CIITA expression in IRF-2 knock-out mice. Both basal and IFN-gamma induced CIITA expression were reduced in IRF-2 knock-out mice. At least half of the amount of inducible CIITA mRNA depends on IRF-2. The reduction of IFN-gamma induced CIITA mRNA in IRF-2 knock-out mice was due to the reduction of the type IV CIITA mRNA induction. The reduction of basal CIITA mRNA was apparently due to the reduction of CIITA mRNA originating from other promoters. These data indicate that IRF-2, like IRF-1, plays a critical role in the regulation of the endogenous CIITA gene. The implications in understanding the previously described phenotypes of IRF-2 defective mice are discussed.

Varying functions of specific major histocompatibility class II transactivator promoter III and IV elements in melanoma cell lines

Melanoma cells commonly express MHC class II molecules constitutively. This is a rare, or possibly unique, phenotype for a nonprofessional antigen-presenting cell, where MHC class II expression ordinarily occurs only after IFN-gamma treatment. Despite the fact that constitutive expression of MHC class II on melanoma cells has been observed for decades and that the regulation of the MHC class II genes is well understood for many different cell types, there is no data regarding the basis for constitutive MHC class II expression in melanoma cells. Here we report that MHC class II expression in melanoma cells can be traced to constitutive expression of the class II transactivator protein (CIITA), which mediates both IFN-gamma-inducible and -constitutive MHC class II expression in all other cell types. In addition, we determined that constitutive CIITA expression is the result of the activation of both the B cell-specific CIITA promoter III and the IFN-gamma-inducible CIITA promoter IV, the latter of which previously has never been known to function as a constitutive promoter in any cell type. The recently described B cell-related ARE-1 activity is important for promoter III activation in the melanoma cells. Constitutive promoter IV activation involves the IFN regulatory factor element (IRF-E), which binds members of the IRF family of proteins, although the major, IFN-gamma inducible member of this family, IRF-1, is not constitutively expressed in these cells. In cells with constitutively active promoter IV, the promoter IV IRF-E is most likely activated by IRF-2. The relevance of these results to the pathway of melanoma development is discussed.

Provider type and the receipt of general and diabetes-related preventive health services among patients with diabetes

OBJECTIVE

Using a measure of provider type that includes "shared care" to determine the contribution of provider type on receipt of general and diabetes-related preventive health services.

METHODS

Automated clinical and administrative data were used to identify adult patients with type 1 and 2 diabetes receiving care from a multispecialty, salaried group practice and enrolled in a large health maintenance organization between 3/97 and 2/98 (n = 10,991). Logistic regression models were fit using generalized estimating equation approaches to evaluate the contribution of provider type on service receipt.

MEASURES

Preventive service receipt included receipt of glycated hemoglobin and lipid testing, retinal examinations, pneumococcal vaccines, Papanicolaou (Pap) smears, and mammograms. Multivariable analyses adjusted for age, sex, race, marital status, household income, diabetes-related comorbidities and complications, prescription drug use, laboratory testing results, and frequency of medical care contact.

RESULTS

Patients seeing an endocrinologist and primary care physician (PCP) were more likely than those seeing endocrinologists alone to receive glycated hemoglobin testing (OR, 1.42), lipid testing (OR, 1.72), mammograms (OR, 2.12), and Pap smears (OR, 2.36), and more likely than those seeing PCPs alone to receive glycated hemoglobin testing (OR, 1.79), lipid testing (OR, 1.54), retinal examinations (OR, 1.33), and mammograms (OR, 1.43). Compared with patients seeing PCPs only, patient's seeing endocrinologists only were more likely to receive retinal examinations (OR, 1.37) and less likely to receive Pap smears (OR, 0.46).

CONCLUSIONS

Care delivered by no one single provider type is associated with greater receipt of all recommended services. Instead, patients seeing both an endocrinologist and a PCP are most likely to receive recommended services.

Dystrophin disruption might be related to myocardial cell apoptosis caused by isoproterenol

Sarcolemma integrity is stabilized by the dystrophin-associated glycoprotein complex that connects actin and laminin-2 in contractile machinery and the extracellular matrix, respectively. Interruption of the connection by the primary gene defect or acquired pathological burden can cause cardiac failure. The purposes of the present study were to verify whether dystrophin is disrupted in acute myocardial injury after the isoproterenol overload (10 mg/kg) and to examine its relation to myocardial cell apoptosis in rats. This injury from 4-16 h at the subendocardium was accompanied by dystrophin disruption and dislocation from subsarcolemma to cytoplasm, which were confirmed by immunohistology and Western blotting. However, delta-sarcoglycan was thoroughly preserved in sarcolemma. The dystrophin degradation preceded the appearance of apoptotic cells and exactly coincided with the transferase-mediated dUTP-biotin nick end labeling-positive cardiomyocytes (TUNEL), as was verified by double-staining. These data suggest that beta-adrenergic stimulation induces dystrophin breakdown followed by apoptosis.

Purine catabolism in Escherichia coli and function of xanthine dehydrogenase in purine salvage

Escherichia coli is not known to utilize purines, other than adenine and adenosine, as nitrogen sources. We reinvestigated purine catabolism because a computer analysis suggested several potential sigma(54)-dependent promoters within a 23-gene cluster whose products have homology to purine catabolic enzymes. Our results did not provide conclusive evidence that the sigma(54)-dependent promoters are active. Nonetheless, our results suggest that some of the genes are metabolically significant. We found that even though several purines did not support growth as the sole nitrogen source, they did stimulate growth with aspartate as the nitrogen source. Cells produced (14)CO(2) from minimal medium containing [(14)C]adenine, which implies allantoin production. However, neither ammonia nor carbamoyl phosphate was produced, which implies that purine catabolism is incomplete and does not provide nitrogen during nitrogen-limited growth. We constructed strains with deletions of two genes whose products might catalyze the first reaction of purine catabolism. Deletion of one eliminated (14)CO(2) production from [(14)C]adenine, which implies that its product is necessary for xanthine dehydrogenase activity. We changed the name of this gene to xdhA. The xdhA mutant grew faster with aspartate as a nitrogen source. The mutant also exhibited sensitivity to adenine, which guanosine partially reversed. Adenine sensitivity has been previously associated with defective purine salvage resulting from impaired synthesis of guanine nucleotides from adenine. We propose that xanthine dehydrogenase contributes to this purine interconversion.

Interferon regulatory factor-2 point mutations in human pancreatic tumors

Interferon regulatory factor (IRF)-2, a member of the IRF family, is a transcription factor involved in the regulation of various interferon and virus-stimulated genes and other genes. For example, IRF-2 is an activator of the interferon (IFN)-gamma-inducible MHC class II transactivator (CIITA) type IV promoter. It cooperates with IRF-1 in the activation of the CIITA type IV promoter and can co-occupy the IRF-E of the promoter with IRF-1. In a previous study, we identified an inactivating point mutation in the DNA binding domain of IRF-2 expressed in a human pancreatic tumor cell line that does not express CIITA or MHC class II in response to IFN-gamma. To further assess the potential impact of IRF-2 mutations in tumorigenesis, we screened fresh pancreatic tumor explants and identified 2 IRF-2 point mutations in the 2 alleles of IRF-2 from a single tumor specimen. Both mutations occurred in the DNA binding domain of IRF-2. DNA binding assays demonstrated that the IRF-2 point mutations impaired IRF-2 DNA binding. The transactivation function of the mutant IRF-2s was similarly impaired. This is the first report of IRF-2 mutations in human tumor explants.