Cancer Treatment Among the Elderly in the United States: Complexities of Aging and Comorbidities

Background: As the life expectancy of Americans becomes longer, the number of individuals who are diagnosed with cancer and other comorbidities increases rapidly. Management of these patients can become increasingly complicated as physicians administer multiple combinations of drugs and therapies. However, the complexities of how age and comorbidities affect receipt of cancer treatment are not well understood. Aim: To explore the association between age, comorbidities, and subsequent cancer treatment in the elderly diagnosed with the four most common types of cancer in the United States. Methods: We used SEER-Medicare data, which covers 28% of the U.S. population, to explore the association between age, comorbidities, and receipt of cancer treatment within 6 months of diagnosis in 727,136 individuals over 65 years old and diagnosed with breast, colorectal, lung, and prostate cancer from 1992-2011. Comorbidity burden was measured using the Charlson Comorbidity Index (CCI) and analyzed as four quantities (Q1: lowest CCI score to Q4: highest CCI score). Poisson regression models were used to assess the associations between comorbidities and cancer treatment, and whether age modified this relationship. Results: Cancer treatment proportion declined rapidly with age for all cancers while median CCI scores increased with age among breast, colorectal, prostate cancer patients and appeared stable among lung cancer patients. For example, individuals aged 76-99 had higher CCI scores ( P < 0.001) and were less likely to be treated (69.8% vs. 81.1% of those age 66-75 year; P < 0.001). After adjustment for potential confounders, we found that high CCI scores (Q3-Q4) were associated with substantially lower cancer treatment rates compared to low CCI score (Q1) in all cancer patients aged 76-99. Regarding individuals aged 66-75, high CCI scores (Q3-Q4) were not associated with lower colorectal cancer treatment rates, and only the highest CCI score group (Q4) was associated with a modest reduction in breast and prostate cancer treatment rates compared to low CCI score (Q1) (PR [95% CI]: 0.97 [0.95-0.99] and 0.91 [0.88-0.93], respectively). Additional multivariable analysis showed that older patients (aged 76-99) with low CCI score (Q1-Q2) had equal or lower treatment rates compared to younger patients (aged 66-75) with the highest CCI scores (Q4). Conclusion: Our findings suggested that among those aged 66-75 years, comorbidities are less likely to influence the receipt of treatment when compared to individuals aged 76-99. The potential harms and benefits of treatment given these age by comorbidity interactions are not clear, but using curative interventions that only have a modest benefit in a highly comorbid aging population could potentially decrease patients' quality of life.

Drug Resistance and Gene Transfer Mechanisms in Respiratory/Oral Bacteria

Growing evidence suggests the existence of new antibiotic resistance mechanisms. Recent studies have revealed that quorum-quenching enzymes, such as MacQ, are involved in both antibiotic resistance and cell-cell communication. Furthermore, some small bacterial regulatory RNAs, classified into RNA attenuators and small RNAs, modulate the expression of resistance genes. For example, small RNA sprX, can shape bacterial resistance to glycopeptide antibiotics via specific downregulation of protein SpoVG. Moreover, some bacterial lipocalins capture antibiotics in the extracellular space, contributing to severe multidrug resistance. But this defense mechanism may be influenced by Agr-regulated toxins and liposoluble vitamins. Outer membrane porin proteins and efflux pumps can influence intracellular concentrations of antibiotics. Alterations in target enzymes or antibiotics prevent binding to targets, which act to confer high levels of resistance in respiratory/oral bacteria. As described recently, horizontal gene transfer, including conjugation, transduction and transformation, is common in respiratory/oral microflora. Many conjugative transposons and plasmids discovered to date encode antibiotic resistance proteins and can be transferred from donor bacteria to transient recipient bacteria. New classes of mobile genetic elements are also being identified. For example, nucleic acids that circulate in the bloodstream (circulating nucleic acids) can integrate into the host cell genome by up-regulation of DNA damage and repair pathways. With multidrug resistant bacteria on the rise, new drugs have been developed to combate bacterial antibiotic resistance, such as innate defense regulators, reactive oxygen species and microbial volatile compounds. This review summaries various aspects and mechanisms of antibiotic resistance in the respiratory/oral microbiota. A better understanding of these mechanisms will facilitate minimization of the emergence of antibiotic resistance.

[The influencing factors of anemia for pregnant women between 2010-2012 in China]

Objective: To investigate the prevalence of anemia and related risk factors for pregnant women in China. Method: Based on Chinese National Nutrition and Health Surveillance 2010-2012, a total of 3 501 pregnant women were investigated from 150 counties of 31 provinces, municipalities and autonomous regions in China, using a multi-stage stratified cluster randomization sampling method. General information of pregnant women, health status, and food intake during the gestation, was collected through a questionnaire investigation. 6 ml fasting venous blood was collected for the determination of hemoglobin concentration. Data were analyzed using multiple logistic regression to investigate the prevalence of anemia and the related influencing factors. Results: The 605 of 3 501 pregnant women had anemia. The prevalence of anemia was 17.2%; and mild anemia accounted for about 61.0% (369/605). Compared with the pregnant women living in the large cities, the OR (95%CI) of those living in the poor rural areas was 1.46 (1.08-1.98). Compared with the pregnant women living in the south area of China, the OR (95%CI) of those living in the north area of China was 1.39 (1.15-1.68); Compared with the pregnant women in the first trimester, the OR (95%CI) of those in the second trimester and the third trimester were 1.79 (1.33-2.43) and 2.11 (1.56-2.85), respectively. The OR (95%CI) of pregnant women who had used folic acid supplementation within the 6 months prior to gestation was 0.76 (0.63-0.93) compared with those who had not used. Conclusion: From 2010 to 2012, the epidemic characteristics of anemia was mild for the pregnant women in China, and pregnant women residential areas, periods of pregnancy and whether to take folic acid were related to anemia.

[Expression and clinical significance of MIIP and PAK1 in endometrial carcinoma]

Objective: To investigate the expressions of migration and invasion inhibitory protein (MIIP) and p21-activated kinase 1 (PAK1) in endometrial carcinoma (EC) and their correlation with clinicopathological features. Methods: The protein levels of MIIP and PAK1 in 135 paraffin-embedded EC tissues, 55 atypical hyperplasia of endometrium (AHE) and 88 normal endometrium (NE) tissues were quantified by immunohistochemistry, the clincial significance and the relationship of these two proteins were also analyzed. Results: The positive rates of MIIP expression in NE, AHE and EC tissues were 52.3%(46/88), 41.8% (23/55) and 34.8% (47/135), respectively. The expression of MIIP in EC was significantly lower than that of MIIP in NE (P<0.05). The positive rates of PAK1 expression in NE, AHE and EC tissues were 45.5% (40/88), 50.9% (28/55) and 62.2% (84/135), respectively. The expression of PAK1 in EC tissues was significantly higher than that of PAK1 in NE tissues (P<0.05). The expression of MIIP in EC tissues was significantly associated with myometrial invasion, International Federation of Gynaecology and Obstetrics (FIGO) stage and lymph node metastasis (P<0.05). The expression of PAK1 in EC tissues was significantly related with differentiation, myometrial invasion, FIGO stage and lymph node metastasis (P<0.05). The expressions of MIIP and PAK1 in EC tissues were marginally related with the overall survival of patients (P=0.092, P=0.052). The expression of MIIP in EC was negatively correlated with PAK1 (r=-0.329, P<0.001). Conclusions: The down-regulation of MIIP and up-regualtion of PAK1 paticipate in the initiation and development of EC, which are correlated with the poor prognosis of EC. The protein expression of MIIP is inversely related with PAK1 in EC.

Visualisation of insect tracheal systems by lactic acid immersion

The endeavours to reveal the tracheal system of insects and some arachnids has a long history. The traditional way to observe a tracheal system in an insect body is by utilising the glycerin immersion method. In this study, we developed the lactic acid immersion method, which reveals a more complete tracheal system. By mounting various types of live specimens or body parts directly into lactic acid, multiple intact and complex tracheal systems were clearly visualised. The lactic acid immersion contributed to revealing tracheal systems by penetrating body tissue while reserving enough time for observation before the penetration of the tracheae. Preliminary comparisons were conducted between lactic acid and other mediae, including glycerin. It turned out that lactic acid immersion provides better details and more distinct structures. In our test, the optimal time for observing the tracheal system was 10-25 min after the organism was immersed in lactic acid.

Molecular epidemiology and genetic diversity of duck hepatitis A virus type 3 in Shandong province of China, 2012-2014

 The infections with duck hepatitis A virus type 3 (DHAV-3) become common in eastern Asia. To better understand the molecular evolution and genetic variation of DHAV-3, a total of 482 dead Cherry Valley duckling liver samples collected from Shandong province of China during 2012-2014 were tested, and the complete P1 coding sequences of 18 DHAV-3 strains were analyzed. The detection rate of DHAV-3 was 64.5% (311/482) in clinical liver samples and 73.0% (92/126) in duckling flocks. The P1 genes of the 18 DHAV-3 isolates shared 91.9%-99.0% nucleotide similarity and 95.2%-100% amino acid similarity with those of the other 26 reference strains. Based on the P1 and VP1 gene sequences, phylogenetic analysis results indicated that the genotyping of DHAV-3 strains presented a distinct geographical distribution. Except B63 strain, all Chinese strains isolated from different host species (duck or goose) at different time were classed into the CH genotype. All Korean and Vietnamese strains belonged to the KV genotype, and all the Korean strains were clustered into KV1 subgenotype, while B63 strain and the Vietnamese strains from different host species (duck or goose) were clustered into KV2 subgenotype. Ten variable amino acid residues were highly conserved within genotypes or subgenotypes in the VP0, VP3 and VP1, respectively, which were possibly the geographic molecular markers of DHAV-3. To the best of our knowledge, this is the first study about the genetic variation of the P1 gene of different DHAV-3 strains, which will be helpful for understanding of the molecular epidemiology of DHAV-3.

Cystathionine γ-Lyase Is Involved in the Renoprotective Effect of Brief and Repeated Ischemic Postconditioning After Renal Ischemia/Reperfusion Injury in Diabetes Mellitus

BACKGROUND

The aim of this study was to determine whether the protective effects of brief and repeated ischemic postconditioning (IPoC) are associated with the modulation of cystathionine γ-lyase (CSE) expression after renal ischemia/reperfusion (I/R) injury in diabetes mellitus (DM).

METHODS

We subjected diabetic rats to 45 minutes of ischemia followed by reperfusion at 24 hours. Before reperfusion, diabetic rats were treated with 3 cycles of 6 seconds of reperfusion, followed by 6 seconds of ischemia. DL-Propargylglycine (PAG, a CSE inhibitor) was administered to the diabetic rats to investigate its effects on the severity of renal I/R injury in diabetes mellitus (DM). Blood samples and left kidneys were collected for the measurement of blood urea nitrogen (BUN) and serum creatinine (SCr) levels and renal pathologic changes. Western blot and immunochemistry techniques were also performed for the localization of CSE. Levels of superoxidase dismutase (SOD), malonyldialdehyde (MDA), tumor necrosis-alpha (TNF-α), and hydrogen sulfide (H₂S) were quantified using commercially available kits.

RESULTS

The results showed that BUN and SCr levels increased on renal ischemia/reperfusion injury (RI/RI) in the DM group. Diabetic rats treated with IPoC exhibited significantly less renal damage on I/R. Kit measurements showed that IPoC could markedly inhibit the levels of MDA and TNF-α and also improve SOD and H₂S levels. Western blot and immunochemistry showed that expression of CSE was downregulated on I/R in the DM group and IPoC upregulated CSE expression, whereas PAG treatment resulted in opposite effects.

CONCLUSION

Our findings show that brief and repeated IPoC increased the expression of CSE after I/R in DM, and the modulation of CSE may underlie the renoprotective effect of IPoC.

Study on titanium-magnesium composites with bicontinuous structure fabricated by powder metallurgy and ultrasonic infiltration

Titanium-magnesium (Ti-Mg) composites with bicontinuous structure have been successfully fabricated by powder metallurgy and ultrasonic infiltration for biomaterial potential. In the composites, Ti phase is distributed continuously by sintering necks, while Mg phase is also continuous, distributing at the interconnected pores surrounding the Ti phase. The results showed that the fabricated Ti-Mg composites exhibited low modulus and high strength, which are very suitable for load bearing biomedical materials. The composites with 100 µm and 230 µm particle sizes exhibited Young's modulus of 37.6 GPa and 23.4 GPa, 500.7 MPa and 340 MPa of compressive strength and 631.5 MPa and 375.2 MPa of bending strength, respectively. Moreover, both of the modulus and strength of the composites increase with decreasing of Ti particle sizes. In vitro study has been done for the preliminary evaluation of the Ti-Mg composites.

Duck "beak atrophy and dwarfism syndrome" disease complex: Interplay of novel goose parvovirus-related virus and duck circovirus?

As a newly emerged infectious disease, duck "beak atrophy and dwarfism syndrome (BADS)" disease has caused huge economic losses to waterfowl industry in China since 2015. Novel goose parvovirus-related virus (NGPV) is believed the main pathogen of BADS disease; however, BADS is rarely reproduced by infecting ducks with NGPV alone. As avian circovirus infection causes clinical symptoms similar to BADS, duck circovirus (DuCV) is suspected the minor pathogen of BADS disease. In this study, an investigation was carried out to determine the coinfection of NGPV and DuCV in duck embryos and in ducks with BADS disease. According to our study, the coinfection of emerging NGPV and DuCV was prevalent in East China (Shandong, Jiangsu and Anhui province) and could be vertical transmitted, indicating their cooperative roles in duck BADS disease.