Anaerobic digestion of microalgal biomass for bioenergy production, removal of nutrients and microcystin: current status

Using renewable microalgal biomass as active feedstocks for biofuels and bioproducts is explored to substitute petroleum-based fuels and chemicals. In the last few years, the importance of microalgae biomass has been realized as a renewable feedstock due to several positive attributes associated with it. Biorefinery via anaerobic digestion (AD) of microalgal biomass is a promising and sustainable method to produce value-added chemicals, edible products and biofuels. Microalgal biomass pretreatment is a significant process to enhance methane production by AD. Findings on the AD microbial community's variety and organization can give novel in turn on digester steadiness and presentation. This review presents a vital study of the existing facts on the AD microbial community and AD production. Co-digestion of microalgal biomass with different co-substrates was used in AD to enhance biogas production, and the process was economically viable with improved biodegradability. Microcystins, which are produced by toxic cyanobacterial blooms, create a severe hazard to environmental health. Anaerobic biodegradation is an effective method to degrade the microcystins and convert into nontoxic products. However, for the cost-effective conversion of biomass to energy and other beneficial byproducts, additional highly developed research is still required for large-scale AD of microalgal biomass.

Persistent chest pain at 1-year predicts long-term angina hospitalization in women with and without obstructive coronary artery disease: results from Women's Ischemia Syndrome Evaluation (WISE)

Background

There is growing evidence that women with ischemia and no obstructive coronary artery disease (INOCA) have an increased risk of major adverse cardiovascular events (MACE). Half of these women continue to experience persistent chest pain (PChP); however longer-term outcomes are unknown.

Purpose

To investigate the relationships between PChP at 1-year with obstructive and nonobstructive coronary artery disease (CAD) and longer-term all-cause mortality, MACE and angina hospitalization in women with suspected myocardial ischemia.

Methods

We studied 673 women with chest pain undergoing coronary angiography for suspected myocardial ischemia in the National Heart, Lung, and Blood Institute Women's Ischemia Syndrome Evaluation (WISE) study. PChP was defined as self-reported continuing chest pain at 1-year, obstructive CAD as >50 stenosis in any coronary artery and non-obstructive CAD was further divided as <20% stenosis and 20–50% stenosis in any coronary artery. The Kaplan-Meier method was used to estimate cumulative incidence rates of all-cause mortality, MACE, and angina hospitalization. Proportional hazards regression estimated adjusted hazard ratios of mortality, MACE and angina hospitalization in relation to PChP at 1-year in obstructive and nonobstructive CAD.

Results

The median age was 58 years, 45% had PChP, and 39% had obstructive CAD with a median follow-up time of 9 years (range 1 to 11) for mortality and 5 years (range 0 to 9) for MACE and anginal hospitalization. There was no difference in mortality or MACE in women with PChP compared to women without PChP in any of the 3 groups (<20%, 20–50%, or >50% CAD), however differences were noted in long-term angina hospitalization (Figure 1). Notably,angina hospitalization rates in women with PChP and nonobstructive CAD were 2.2 times those of women without PChP, and comparable to those of women with obstructive CAD and no PChP (p<0.0001).

Conclusions

Among women undergoing coronary angiography for suspected myocardial ischemia, women with nonobstructive CAD and PChP have rates of angina hospitalization comparable to patients with obstructive CAD without PChP. Thus, PChP increases the hazard of long term anginal hospitalization regardless of the presence or absence of obstructive CAD. Given the economic burden of angina hospitalization, further studies are needed to determine whether aggressive treatment in women with PChP without obstructive CAD changes outcomes and impact on the health care system.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health (NIH)

Role of physical fitness in the obesity paradox. Long-term major adverse cardiovascular events in the Women's Ischemia Syndrome Evaluation (WISE)

Background

Emerging data suggests there is an “obesity paradox” where obesity may be protective against cardiovascular morbidity and mortality in patients with cardiovascular disease. However, weight status primarily assessed through body mass index (BMI) is limited in its ability to discern contributions from fat vs. lean muscle mass. Most studies on BMI have not accounted for physical fitness, which is a known modifier of weight status and a potential mediator of effects of obesity on major adverse cardiovascular events (MACE).

Purpose

To investigate the relationship between BMI and physical fitness, measured by self-reported Duke Activity Status Index (DASI) score, with long-term MACE in women evaluated for suspected myocardial ischemia.

Methods

The National Heart, Lung, and Blood Institute Women's Ischemia Syndrome Evaluation (WISE) study is a multicenter prospective cohort study. From 1996–2000, 936 women were enrolled at the time of clinically indicated coronary angiography and assessed with a median follow up of 5.8 (range 0–9 years) for MACE. MACE was defined as a composite of death, nonfatal myocardial infarction, stroke, or congestive heart failure. Proportional hazards regression was used to estimate adjusted hazard ratios of MACE in relation to metabolic status and physical fitness. DASI scores ≥25, equivalent to ≥7 metabolic equivalents [METs]) was used as cut point to define high physical fitness, in our prior studies DASI >25 approximates completion of the second stage of a Bruce treadmill protocol.

Results

Among the 899 women with complete data, 69.5% had low physical fitness (DASI scores <25), 34.9% overweight (BMl ≥25 to 30), 40.5% obese (BMI ≥30). In fit women, obesity was associated with lower hazard ratio for MACE (HR 0.64, p=0.01); while low fitness in normal weight women was associated with 60% excess risk of MACE (HR 1.61, p=0.01) (Figure 1).

Conclusions

Among women undergoing coronary angiography for suspected myocardial ischemia, obesity was inversely related with long-term MACE in physically fit women. Our findings suggest that physical fitness may play a role in the obesity paradox. These results support the inclusion of fitness in understanding the relations between body weight and long-term MACE. The DASI is a simple, self reported tool that can identify higher-risk symptomatic women and should be considered in future investigations and routine examination of normal, overweight and obese women.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): U01 HL064829

The effect of Clostridium tyrobutyricum Spo0A overexpression in the intestine of mice

Clostridium tyrobutyricum shows probiotic properties and can affect the composition of gut microbiota and regulate the intestinal immune system. Compared with other probiotics, this spore-producing bacterium shows unparalleled advantages in commercial production. In addition to being resistant to extreme living environments for extended periods, its endophytic spores are implicated in inhibiting cancer cell growth. We speculated that C. tyrobutyricum spores can also promote gut health, which mean it can maintain intestinal homeostasis. To date, the beneficial effects of C. tyrobutyricum spores on gut health have not been reported. In this study, a Spo0A-overexpressing C. tyrobutyricum strain was developed to increase spore production, and its probiotic effects on the gut were assessed. Compared with the wild-type, the engineered strain showed significantly increased sporulation rates. Mice administered with the engineered strain exhibited enhanced intestinal villi and the villus height/crypt depth ratio, weight gain and improved Firmicutes/Bacteroidetes ratio to facilitate intestinal homeostasis. This study demonstrated for the first time that enhanced spore production in C. tyrobutyricum can improve intestinal homeostasis, which is advantageous for its commercial application in food and pharmaceutical industry.

[Intrauterine balloon tamponade combined with temporary abdominal aortic balloon occlusion in the management of women with placenta accreta spectrum:a randomized controlled trial]

Objective: To access the effectiveness and safety of the intrauterine balloon tamponade verse gauze packing combined with temporary abdominal aortic balloon occlusion in the management of placenta accreta spectrum (PAS). Methods: This was an open-label, randomized controlled trial conducted in Nanjing Drum Tower Hospital. The patients suspected with PAS for uterine preservation surgery under the multidisciplinary team care were recruited between Aug 2015 and Jan 2018. When bleeding could not be achieved after fetus delivered, and a temporary abdominal aortic balloon occlusion and the compression sutures as needed, the women were randomly allocated 1∶1 into balloon tamponade (n=81) or gauze packing (n=80) group. The primary outcome was successful bleeding arrests by avoiding second line surgeries. The secondary outcomes included the volume of blood loss during and after cesarean section, the rate of PPH, incidence and amount of blood transfusion, hysterectomy, postpartum pain, ICU admission, need for re-laparotomy, and the length of hospital stay, readmission, and interventional radiology complications. Results: All the women [100% (81/81)] in the balloon group were obtained hemostasis without further intervention, significantly higher than 88% (70/80) in the gauze group (P=0.001). Before uterine tamponade, blood loss were 820 ml (620-1 230) ml and 850 ml (605-1 442) ml, while placenta bed were sutured in 96%（78/81, 77/80） respectively (P>0.05).The proportion of blood loss≥1 000 ml was higher in the gauze group than that in the balloon group (P=0.006). Maternal adverse events involving total blood loss, puerperal morbidity and postpartum pain occurred more frequently in the gauze group (P<0.05). The following outcome showed no statistically significant difference between the two groups: the vascular occlusion time, the dose of radiation, and interventional radiology complication (P>0.05). The median volume infused into the lower and upper balloons is 70 ml (50-100 ml) and 180 ml (100-240 ml). Conclusions: Incrauterine balloon tamponade is as effective as gauze packing in hemostasis following the placenta delivery in PAS. Compared with gauze packing, the uterine balloon tamponade is more effective.

Proton transport enabled by a field-induced metallic state in a semiconductor heterostructure

Tuning a semiconductor to function as a fast proton conductor is an emerging strategy in the rapidly developing field of proton ceramic fuel cells (PCFCs). The key challenge for PCFC researchers is to formulate the proton-conducting electrolyte with conductivity above 0.1 siemens per centimeter at low temperatures (300 to 600°C). Here we present a methodology to design an enhanced proton conductor by means of a Na _x CoO₂/CeO₂ semiconductor heterostructure, in which a field-induced metallic state at the interface accelerates proton transport. We developed a PCFC with an ionic conductivity of 0.30 siemens per centimeter and a power output of 1 watt per square centimeter at 520°C. Through our semiconductor heterostructure approach, our results provide insight into the proton transport mechanism, which may also improve ionic transport in other energy applications.

[The status and related factors of myopia for children and adolescents aged 5-18 years old in Shaanxi Province in 2018]

In 2018, the myopia detection rate of children and adolescents aged 5-18 years old in Shaanxi Province was 54.9% (11 060/20 144). The myopia detection rate of girls ［58.6%(5 830/9 949)］ was higher than that of boys ［58.6% (3 416/5 830)］ (P<0.001). In children and adolescents, the myopia detection rate increased with the age before their 16 years old, and saw a stable or downward trend after the age of 16. After adjusting the confounding factors, the myopia detection rate of children and adolescents from regions with per capita GDP>100 000 yuan was higherthan that of children and adolescents from regions with per capita GDP<50 000 yuan［OR (95%CI):1.58(1.34-1.87)］.

Negative Correlation Between Serum Levels of Homocysteine and Apolipoprotein M

BACKGROUND

Homocysteine (Hcy) has been suggested as an independent risk factor for atherosclerosis. Apolipoprotein M (apoM) is a constituent of the HDL particles. The goal of this study was to examine the serum levels of homocysteine and apoM and to determine whether homocysteine influences apoM synthesis.

METHODS

Serum levels of apoM and Hcy in 17 hyperhomocysteinemia (HHcy) patients and 19 controls were measured and their correlations were analyzed. Different concentrations of homocysteine (Hcy) and LY294002, a specific phosphoinositide 3- kinase (PI3K) inhibitor, were used to treat HepG2 cells. The mRNA levels were determined by RT-PCR and the apoM protein mass was measured by western blot.

RESULTS

We found that decreased serum apoM levels corresponded with serum HDL levels in HHcy patients, while the serum apoM levels showed a statistically significant negative correlation with the serum Hcy levels. Moreover, apoM mRNA and protein levels were significantly decreased after the administration of Hcy in HepG2 cells, and this effect could be abolished by addition of LY294002.

CONCLUSIONS

Present study demonstrates that Hcy downregulates the expression of apoM by mechanisms involving the PI3K signal pathway.

SAT0453 DELAYED DENOSUMAB INJECTIONS AND FRACTURES RISK AMONG SUBJECTS WITH OSTEOPOROSIS: A POPULATION-BASED COHORT STUDY

Background:

Denosumab is effective for osteoporosis, but discontinuation leads to rapid reversal of its therapeutic effect[1].

Objectives:

To estimate the risk for fracture among users of denosumab who delayed subsequent dosages compared with users who received dosages on time.

Methods:

Population-based cohort study. We included patients aged over 45 years who initiated denosumab for osteoporosis from UK THIN database, 2010 to 2019. Observational data were used to “emulate a hypothetical trial”[2, 3] with three dosing intervals: subsequent denosumab injection 24-28 weeks after prior dose (“on time”), delay by 4-16 weeks (“short delay”), and delay by over 16 weeks (“long delay”). The primary outcome was a composite of all fracture types. Secondary outcomes included major osteoporotic fracture, vertebral fracture, and hip fracture.

Results:

The rate of composite fracture per 1000 person-years was 58.9 for on-time, 61.7 for short delay, and 85.4 for long delay of subsequent denosumab injections. Compared to on-time injections, short delay had a hazard ratio (HR) for composite fracture 1.03 (95% CI 0.63-1.69) and long delay HR 1.44 (95% CI 0.96-2.17; p for trend 0.093). For major osteoporotic fractures, short delay had an HR 0.94 (95% CI 0.57-1.55) and long delay an HR of 1.69 (95% CI 1.01-2.83; p for trend 0.056). For vertebral fractures, short delay had an HR 1.48 (95% CI 0.58-3.79) and long delay 3.91 (95% CI 1.62-9.45; p for trend 0.005).

Conclusion:

While delayed subsequent denosumab dosages over 16 weeks was associated with an increased risk of vertebral and major osteoporotic fracture compared to no delay, composite fracture risk was not increased with longer delays.

References:

[1]Cummings SR, Ferrari S, Eastell R, et al. Vertebral Fractures After Discontinuation of Denosumab: A Post Hoc Analysis of the Randomized Placebo-Controlled FREEDOM Trial and Its Extension. J Bone Miner Res, 2017.

[2]Hernán MA. How to estimate the effect of treatment duration on survival outcomes using observational data. BMJ 2018.

[3]Hernán MA, Robins JM. Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available. Am J Epidemiol 2016.

Table.

Rates and Adjusted Hazard Ratios of Fracture

On-timeShort delayLong delayP for linear trendComposite FractureRate (per 1000 person-years)5961.785.4-Unadjusted HR (95 %)Ref1.05 (0.62, 1.76)1.45 (0.95, 2.21)0.097Adjusted HR (95% CI)†Ref1.03 (0.63, 1.69)1.44 (0.96, 2.17)0.093Major Osteoporotic FractureRate (per 1000 person-years)34.831.958-Unadjusted HR (95 %)Ref0.92 (0.55, 1.53)1.67 (0.98, 2.84)0.074Adjusted HR (95% CI)†Ref0.94 (0.57, 1.55)1.69 (1.01, 2.83)0.056Vertebral FractureRate (per 1000 person-years)4.97.319.4-Unadjusted HR (95 %)Ref1.47 (0.58, 3.71)3.93 (1.59, 9.72)0.006Adjusted HR (95% CI)†Ref1.48 (0.58, 3.79)3.91 (1.62, 9.45)0.005Hip FractureRate (per 1000 person-years)10.29.618.3-Unadjusted HR (95 %)Ref0.94 (0.43, 2.04)1.78 (0.80, 3.97)0.18Adjusted HR (95% CI)†Ref0.97 (0.44, 2.12)1.75 (0.81, 3.79)0.173

†Adjusted model: adjusted by age, sex, baseline CCI index, major osteoporotic fracture, oral BP duration (years), 10-year risk of major osteoporotic fracture, prior denosumab doses.

Acknowledgments:

We acknowledge Dr. Dani Prieto-Alhambra for kindly providing Read codes.

Disclosure of Interests:

Houchen Lyu: None declared, Kazuki Yoshida: None declared, Sizheng Steven Zhao: None declared, Xabier García-Albéniz: None declared, Jie Wei: None declared, Chao Zeng: None declared, Sara Tedeschi: None declared, Benjamin Leder Grant/research support from: Research funding from Amgen, Guanghua Lei: None declared, Peifu Tang: None declared, Daniel Solomon Grant/research support from: Funding from Abbvie and Amgen unrelated to this work

Properties of Neon, Magnesium, and Silicon Primary Cosmic Rays Results from the Alpha Magnetic Spectrometer

We report the observation of new properties of primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in the rigidity range 2.15 GV to 3.0 TV with 1.8×10^{6}  Ne, 2.2×10^{6}  Mg, and 1.6×10^{6}  Si nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The Ne and Mg spectra have identical rigidity dependence above 3.65 GV. The three spectra have identical rigidity dependence above 86.5 GV, deviate from a single power law above 200 GV, and harden in an identical way. Unexpectedly, above 86.5 GV the rigidity dependence of primary cosmic rays Ne, Mg, and Si spectra is different from the rigidity dependence of primary cosmic rays He, C, and O. This shows that the Ne, Mg, and Si and He, C, and O are two different classes of primary cosmic rays.

[The impact of carbapenem-resistance Pseudomonas aeruginosa infections on mortality of patients with hematological disorders]

Objective: To assess the risk factors for mortality and clinical outcome of carbapenem-resistant Pseudomonas aeruginosa (CRPA) infections in patients with hematological disorders. Methods: The data of in-patients with hematological disorders infected by CRPA or carbapenem-susceptible Pseudomonas aeruginosa (CSPA) were recorded in a seven-year retrospective cohort study. Risk factors for CRPA infections and impact of on mortality were identified. The primary end point was 30-day all-cause mortality. Results: A total of 81 patients with PA infections were included in the study, including 58 CSPA and 23 CRPA. Most of the primary diseases were acute leukemia or lymphoma (79.0%, 64/81). The median absolute neutrophil count at infection onset was 0.24×10(9)/L. Independent risk factors associated with carbapenem-resistance included longer duration of hospital stay (P=0.013, OR=1.045) and carbapenem exposure one month prior to infections (P=0.005, OR=8.132). The 30-day all-cause mortality of the whole cohort was 29.6%(24/81), and 30-day attributable mortality was 13.6%(11/81). Pulmonary infection was the leading cause of death, accounting for 41.7%(10/24). The adjusted 30-day mortality rate was significantly higher in patients with CRPA compared with CSPA [60.9%(14/23) vs. 17.2%(10/58), P<0.001, respectively]. CRPA infection was an independent prognostic factor for 30-day mortality(P=0.011, OR=5.427). Other factors included old age, longer duration of neutropenia and poor functional performance. Conclusions: Patients with hematological disorders have high mortality rate and poor prognosis caused by CRPA infections, which mainly develop in lungs.

The feasibility of enzyme hydrolysate gross energy for formulating duck feeds

Two experiments were designed to investigate the feasibility of enzyme hydrolysate gross energy (EHGE) for formulating duck feeds. In experiment 1, six mixed diets and 6 experimental diets (compound feeds) with 20% CP were formulated, and their EHGE, AME, and TME were determined so as to analyze the correlation between EHGE and AME, TME. In experiment 2, six experimental diets with different EHGE levels were further arranged to determine the EHGE requirement for Pekin ducks from hatch to 21 D of age. A total of 384 freshly hatched ducklings was randomly divided into 6 experimental treatments, each treatment containing 8 replicates with 8 ducks per replicate. The results showed that there were a linear correlation between EHGE and AME (r = 0.998, P < 0.01), TME (r = 0.997, P < 0.01) for 6 mixed diets, and the regression models were AME = 0.996 × EHGE−1.062 (R² = 0.996, P < 0.01), TME = 0.997 × EHGE+0.304 (R² = 0.995, P < 0.01). For the 6 experimental diets, EHGE was also positively correlated with AME (r = 0.983, P < 0.01), TME (r = 0.984, P < 0.01), and the regression models were AME = 1.2054 × EHGE−3.180 (R² = 0.967, P < 0.01), TME = 1.2054 × EHGE−1.783 (R² = 0.967, P < 0.01). According to the broken-line model and optimal BW, the EHGE requirement for ducks from hatch to 21 D of age was 2,937 kcal/kg (calculated value), 3,182 kcal/kg (determined value). In conclusion, EHGE could be used to predict the AME and TME values for mixed diets and compound feeds based on established regression models, and the simulated digestion method in vitro has the potential for effective energy evaluation and formulation for duck feeds.

The CLDN5 locus may be involved in the vulnerability to schizophrenia

The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3′-untranslated region of the CLDN5 locus was associated with schizophrenia (χ2= 4.75,P= 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5′-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (χ2) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (χ2= 5.32,P= 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.

A Weak Association of the CLDN5 Locus with Schizophrenia in Chinese Case-control Samples

Background:

An increasing number of studies have described the relationship between velo-cardio-facial syndrome (VCFS) and schizophrenia. in a family-based study, we found that rs10314, a single nucleotide polymorphism (SNP) present in the 3’-flanking region of the CLDN5 gene, was associated with schizophrenia among a Chinese population. High false positive rate is a common problem with the association study of human diseases. It is very important to replicate an initial finding with different samples and experimental designs.

Methods:

A total of 749 patients with schizophrenia and 383 age and sex matched healthy control subjects in Chinese population were recruited. PCR-based RFLP protocol was applied to genotype rs10314 to see its disease association.

Results:

The χ2 goodness-of-fit test showed that the genotypic distributions of rs10314 were in Hardy-Weinberg equilibrium in both the patient group (χ2=1.12, P=0.289) and the control group (χ2=0.22, P=0.639). rs10314 was associated with schizophrenia with an odds ratio (OR) of 1.32 in the male subjects (χ2=5.45, P=0.02, 95% CI 1.05-1.67) but not in the female subjects (χ2=0.64, P=0.425, OR=1.14, 95% CI 0.83-1.57). the χ2 test showed a genotypic association only for combined samples (χ2=7.80, df=2, P=0.02). SNP rs10314 is a G to C base change. Frequency of the genotypes containing the C allele was significantly higher in the patient group than in the control group.

Conclusions:

The present work shows that the CLDN5 gene polymorphism is more likely to be involved in schizophrenic men than women, suggesting that this gene may contribute to the gender differences in schizophrenia.

Comparative Analysis of Gait Speed Estimation Using Wideband and Narrowband Radars, Thermal Camera, and Motion Tracking Suit Technologies

Research has shown that cognitive and physical functioning of older adults can be reflected in indicators such as walking speed. While changes in cognition, mobility, or health cause changes in gait speed, often gradual variations in walking speed go undetected until severe problems arise. Discrete clinical assessments during clinical consultations often fail to detect changes in day-to-day walking speeds and do not reflect walking speeds in everyday environments, where most of the mobility issues happen. In this paper, we compare four walking speed measurement technologies to a GAITRite mat (gold standard): (1) an ultra wideband radar (covering the band from 3.3 GHz to 10 GHz), (2) a narrow band 24-GHz radar (with a bandwidth of 250 MHz), (3) a perception Neuron Motion Tracking suit, and (4) a thermal camera. Data were collected in parallel using all sensors at the same time for 10 healthy adults for normal and slow walking paces. A comparison of the sensors indicates better performance at lower gait speeds, with offsets (when compared to GAITRite) between 0.1 and 20% for the ultra wideband radar, 1.9 and 17% for the narrowband radar, 0.1 and 38% for the thermal camera, and 1.7 and 38% for the suit. This paper supports the potential of unobtrusive radar-based sensors and thermal camera technologies for ambient autonomous gait speed monitoring for contextual, privacy-preserving monitoring of participants in the community.

The role of macrophages during breast cancer development and response to chemotherapy

Macrophages play an important role in the immune system as a key host defense against pathogens. Non-polarized macrophages can differentiate into pro-inflammatory classical pathway-activated macrophages or anti-inflammatory alternative pathway-activated macrophages, both of which play central roles in breast cancer growth and progression in a process called polarization of macrophages. Classical pathway-activated and alternative pathway-activated macrophages can transform into each other and their transformational properties and orientation are determined by cytokines in the tumor microenvironment. Tumor-associated macrophages display many functions, such as tissue reforming, participating in inflammation and tumor growth in breast cancer progression. Some cytokines, such as interleukins and transcriptional activators, reside in the tumor microenvironment and influence tumor-associated macrophages. Chemotherapy is a common treatment for breast cancer and macrophages play an important role in mammary tumor cell migration, cancer invasion, and angiogenesis. This review summarizes the activities of tumor-associated macrophages in the mammary tumor, chemotherapeutic processes and some potential strategies for breast cancer therapy.