Optimizing peripheral blood chromosome analysis: effects of refrigeration time and blood volume.

OBJECTIVE: This study aims to investigate the impact of refrigeration time and blood volume on the success rate of peripheral blood chromosomal analysis using response surface methodology (RSM). METHODS: Peripheral blood samples from 30 volunteers were subjected to chromosomal analysis under different refrigeration duration periods (≤7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days) along with different blood volumes (0.2 mL, 0.3 mL, 0.4 mL, 0.5 mL, 0.6 mL, 0.7 mL, and 0.8 mL). The effects of refrigeration time and blood volume on the success rate of peripheral blood chromosomal analysis were determined using the Chi-square test for trend, followed with Spearman's rank correlation coefficient, and RSM analysis to identify the optimal combination of refrigeration time and blood volume. RESULTS: The refrigeration time within 10 days had a minor impact on the success rate, while refrigeration time more than 11 days significantly decreased the success rate. An increase in blood volume slightly improved the success rate. The success rate showed both linear and nonlinear changes with refrigeration time, while the effect of blood volume was primarily linear. The highest success rate was observed at a refrigeration time of ≤7 days and a blood volume of 0.8 mL. The interaction between refrigeration time and blood volume had a significant impact on the success rate. CONCLUSION: It is recommended to keep the refrigeration time of blood samples within 7 days and control the blood volume at 0.8 mL to maximize the success rate of chromosomal analysis.

Effects of rumen-protective γ-aminobutyric acid additive on lactation performance and serum biochemistry in heat-stressed cows.

In the context of global warming, heat stress has become one of the major stress factors limiting dairy cattle production. Although many methods have been explored to help cows mitigate the negative effects of heat stress during the hot summer months, maintaining the performance of high-yielding cows under heat stress is still a great challenge. The aim of this trial was to investigate the effect of RP-GABA in the diet on milk yield, milk composition and serum biochemical parameters in heat-stressed cows. Twenty Chinese Holstein cows in early lactation (51.00 ± 4.92 kg milk/d, 71 ± 10.94 d in milk and 2.68 ± 0.73 parities) were included in this experiment and randomly divided into four groups (n = 5/group). The four experimental groups consisted of one control group (0 g RP-GABA/d) and three treatment groups, given 5, 7.5 and 10 g RP-GABA/d of dry matter (DM) per cow, respectively. The results showed that supplementing high-yielding cows with 10 g/d of RP-GABA improved milk protein production but had no effect on the improvement of other production performance, the alleviation of heat stress in cows, or the improvement of immune function and antioxidant capacity. Ultimately, we conclude that the supplementation of 10 g/d RP-GABA to heat-stressed, high-yielding dairy cows can provide a degree of performance enhancement. Furthermore, our study provides some reference for nutritional improvement measures for summer heat stress in dairy cows, especially high-yielding cows.

Risk factors for in-hospital death in 2,179 patients with acute aortic dissection.

Background: This study aims to investigate the risk factors for in-hospital death in patients with acute aortic dissection (AAD) and to provide a straightforward prediction model to assist clinicians in determining the outcome of AAD patients. Methods: Retrospective analysis was carried out on 2,179 patients admitted for AAD from March 5, 1999 to April 20, 2018 in Wuhan Union Hospital, China. The risk factors were investigated with univariate and multivariable logistic regression analysis. Results: The patients were divided into two groups: Group A, 953patients (43.7%) with type A AAD; Group B, 1,226 patients (56.3%) with type B AAD. The overall in-hospital mortality rate was 20.3% (194/953) and 4% (50/1,226) in Group A and B respectively. The multivariable analysis included the variables that were statistically significant predictors of in-hospital death (P < 0.05). In Group A, hypotension (OR = 2.01, P = 0.001) and liver dysfunction (OR = 12.95, P < 0.001) were independent risk factors. Tachycardia (OR = 6.08, P < 0.001) and liver dysfunction (OR = 6.36, P < 0.05) were independent risk factors for Group B mortality. The risk factors of Group A were assigned a score equal to their coefficients, and the score of -0.5 was the best point of the risk prediction model. Based on this analysis, we derived a predictive model to help clinicians determine the prognosis of type A AAD patients. Conclusions: This study investigate the independent factors associated with in-hospital death in patients with type A or B aortic dissection, respectively. In addition, we develop the prediction of the prognosis for type A patients and assist clinicians in choosing treatment strategies.

Prognostic impact of branch vessel involvement on organ malperfusion and mid-term survival in patients with acute type A aortic dissection.

BACKGROUND: This study aimed to investigate the impact of branch vessel involvement on organ malperfusion and mid-term survival in patients with acute type A aortic dissection (ATAAD). METHODS: Between January 2019 and December 2020, 493 consecutive patients with angiographically confirmed ATAAD were retrospectively analysed. Preoperative computed tomography angiography parameters (branch artery involvement, longitudinal extent of dissection) were reviewed. The incidence of organ malperfusion, in-hospital mortality, and mid-term outcomes of patients with and without branch vessel involvement were compared. RESULTS: Branch vessel involvement was detected in 407 patients (82.6%), and organ malperfusion was observed in 234 patients (47.5%). The incidence of organ malperfusion was significantly higher in patients with branch vessel involvement compared with patients without it (52.6% vs. 23.3%, p < 0.001). Patients with coronary artery involvement (32.5%) were more likely to manifest as clinical malperfusion, whereas it occurred only 19.4% in patients with renal artery involvement. In-hospital mortality was higher in patients with branch vessel involvement (19.9% vs. 8.1%, p = 0.010). Median follow-up time was 16.1 months. Two-year survival rate was lower in patients with branch vessel involvement (76.3% vs. 84.5%, p = 0.085) or organ malperfusion (68.3% vs. 86.0%, p < 0.001). Multivariable analysis identified cardiac, cerebral, visceral and renal malperfusion as independent predictors for in-hospital mortality. CONCLUSIONS: Only a small proportion of branch vessel involvement was associated with corresponding organ malperfusion in patients with ATAAD. Branch vessel involvement had a greater effect on short-term outcomes than mid-term survival, and organ malperfusion was related to a worse prognosis beyond it.

Effect of elevated fasting blood glucose level on the 1-year mortality and sequelae in hospitalized COVID-19 patients: A bidirectional cohort study.

To observe the predictive effect of fasting blood glucose (FBG) level on the prognosis, clinical sequelae, and pulmonary absorption in hospitalized coronavirus disease 2019 (COVID-19) patients with and without a history of diabetes, respectively, and to evaluate the correlation between the dynamic changes of FBG and poor prognosis. In this bidirectional cohort study, we enrolled 2545 hospitalized COVID-19 patients (439 diabetics and 2106 without a diabetic history) and followed up for 1 year. The patients were divided according to the level of admission FBG. The dynamic changes of FBG were compared between the survival and the death cases. The prediction effect of FBG on 1-year mortality and sequelae was analyzed. The 1-year all cause mortality rate and in-hospital mortality rate of COVID-19 patients were J-curve correlated with FBG (p < 0.001 for both in the nondiabetic history group, p = 0.004 and p = 0.01 in the diabetic history group). FBG ≥ 7.0 mmol/L had a higher risk of developing sequelae (p = 0.025) and have slower recovery of abnormal lung scans (p < 0.001) in patients who denied a history of diabetes. Multivariable Cox regression analysis showed that FBG ≥ 7.0 mmol/L was an independent risk factor for the mortality of COVID-19 regardless of the presence or deny a history of diabetes (hazard atio [HR] = 10.63, 95% confidence interval [CI]: 7.15-15.83, p < 0.001; HR = 3.9, 95% CI: 1.56-9.77, p = 0.004, respectively). Our study shows that FBG ≥ 7.0 mmol/L can be a predictive factor of 1-year all-cause mortality in COVID-19 patients, independent of diabetes history. FBG ≥ 7.0 mmol/L has an advantage in predicting the severity, clinical sequelae, and pulmonary absorption in COVID-19 patients without a history of diabetes. Early detection, timely treatment, and strict control of blood glucose when finding hyperglycemia in COVID-19 patients (with or without diabetes) are critical for their prognosis.

Nucleotides: an updated review of their concentration in breast milk.

Our knowledge about the complexity of human milk, in particular fatty acid, protein, and oligosaccharide profiles, has increased considerably in recent years. However, little attention has been paid to nucleotides, which account for ∼2% to 5% of the nonprotein nitrogen fraction of breast milk and provide important cellular and metabolism functions for the infant. We examined literature published in the past 25 years to provide an updated review of concentrations of nucleotides in breast milk across lactational stages in mothers around the world. The free mononucleotides found in highest concentrations in breast milk are, from highest to lowest in the order of cytidine 5'-monophosphate, uridine 5'-monophosphate, and adenosine 5'-monophosphate, guanosine 5'-monophosphate, and inosine 5'-monophosphate. Levels of nucleotides varied considerably amongst individual mothers and with stage of lactation. They could be further influenced by time of day and season and the mother's diet. Levels of free nucleotides varied between studies undertaken in different regions; however, in studies that measured total potentially available nucleotides levels, regional differences were not apparent. Some studies report higher amounts in colostrum and transition milk compared with mature milk, whereas other studies report the converse. Recently, clinical studies showed that there are benefits to supplement nucleotides in infant formula. Although comparing data in the literature remains a challenge because of different milk collection methodologies and measurement protocols used by different studies, the information may provide insights for designing of formula products for infant at different stages of development.

Changes in HMO Concentrations throughout Lactation: Influencing Factors, Health Effects and Opportunities.

Human milk oligosaccharides (HMOs) are important functional biomolecules in human breast milk. Understanding the factors influencing differences in HMO composition and changes in their concentration over lactation can help to design feeding strategies that are well-adapted to infant's needs. This review summarises the total and individual concentration of HMOs from data published from 1999 to 2019. Studies show that the HMO concentrations are highest in colostrum (average 9-22 g/L), followed by slightly lower concentrations in transitional milk (average 8-19 g/L), with a gradual decline in mature milk as lactation progresses, from 6-15 g/L in breast milk collected within one month of birth, to 4-6 g/L after 6 months. Significant differences in HMO composition have been described between countries. Different HMOs were shown to be predominant over the course of lactation, e.g., 3-fucosyllactose increased over lactation, whereas 2'-fucosyllactose decreased. Recent clinical studies on infant formula supplemented with 2'-fucosyllactose in combination with other oligosaccharides showed its limited beneficial effect on infant health.

[Effect of sample preparation on analysis of human milk endogenous peptides using liquid chromatography-tandem mass spectrometry].

Hundreds of endogenous peptides were released from milk proteins within the human mammary gland and some of them possess a variety of bioactive functions. Thus, it is important to investigate human milk endogenous peptides for infant health. Peptidomics based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been used to investigate human milk endogenous peptides. Extraction of endogenous peptides from human milk is an essential and key procedure for analyzing human milk peptides using LC-MS/MS. This study aimed to compare methods for extracting endogenous peptides from human milk using LC-MS/MS. Ultrafiltration methods including that not involving denaturation (UF 1), that involving heat denaturation (UF 2), and that involving chemical denaturation (UF 3), precipitation methods using trichloroacetic acid (PCPN 1) and alcohol (PCPN 2), and an enrichment method using highly ordered mesoporous carbon (OMC) were used to extract endogenous peptides from human milk. Extracted endogenous peptides were then analyzed using LC-MS/MS. The samples extracted using UF 1 and UF 2 comprised 1161±8 and 1017±91 endogenous peptides, respectively. More than 70% peptide sequences in each sample extracted using UF 1 and UF 2 overlapped. The results revealed that endogenous peptides extracted using UF 1 and UF 2 showed similar characteristics. UF 1 yielded the highest number of peptides, whereas UF 3 extracted the least number of peptides at 366±18. The number of endogenous peptides extracted using PCPN 1 and PCPN 2 were 779±69 and 876±55, respectively. However, their characteristics were quite different, and only about 50% peptide sequences overlapped. The number of peptides extracted using OMC (549±151) was not remarkable compared with that using other methods. However, the isoelectric point (pI) and grand average of hydropathicity (GRAVY) of the peptides extracted using OMC were different from those extracted using other methods. This method presented no selectivity for the endogenous peptides with different pI and GRAVY and may be used to extract unique peptides from human milk. A total of 205 peptides were commonly identified in the samples using each of the six methods. The percent of shared peptides across the six samples ranged from 13% to 23%. The number of unique peptides in the samples extracted using UF 1 and UF 2 (226 and 228, respectively) were the highest among those extracted using the six methods. The results showed that all six methods could be used to extract endogenous peptides from these high-abundance precursor proteins. A total of 21, 38, and 19 peptides were extracted from lactotransferrin using UF 2, UF 3, and OMC, respectively, and the coverage rates of these peptides in lactotransferrin were 14%, 16%, and 19%, respectively. These three methods could extract the endogenous peptides from lactotransferrin in human milk, but PCPN 1 that has been commonly used in previous studies could not. The peptides from ß-casein, polymeric immunoglobulin receptor, osteopontia, αS1-casein, κ-casein, and bile salt-activated lipase were identified in all samples extracted using the six methods. Moreover, these precursor proteins contributed 88% peptides in the samples extracted using the six methods. In conclusion, UF 1 and UF 2 were efficient procedures for extracting endogenous peptides from human milk. In addition, UF 2 could extract peptides from lactotransferrin, which is the optimum choice for extracting endogenous peptides from human milk. Additionally, the OMC enrichment method can be used to enrich and extract specific endogenous peptides from human milk. This study systematically compared the sample preparation methods commonly used in human milk endogenous peptidomics in recent years. The results provide strong support for uniform and standardized sample preparation methods. An ultrafiltration method without denaturation, which is more advantageous than the currently commonly used trichloroacetic acid precipitation method, was also established to prepare human milk endogenous peptide samples. In combination with OMC, this method can help in a more comprehensive and in-depth understanding of the endogenous peptidome of human milk.

One-year mortality and consequences of COVID-19 in cancer patients: A cohort study.

The 1-year mortality and health consequences of COVID-19 in cancer patients are relatively underexplored. In this multicenter cohort study, 166 COVID-19 patients with cancer were compared with 498 non-cancer COVID-19 patients and 498 non-COVID cancer patients. The 1-year all-cause mortality and hospital mortality rates in Cancer COVID-19 Cohort (30% and 20%) were significantly higher than those in COVID-19 Cohort (9% and 8%, both P < .001) and Cancer Cohort (16% and 2%, both P < 0.001). The 12-month all-cause post-discharge mortality rate in survival discharged Cancer COVID-19 Cohort (8%) was higher than that in COVID-19 Cohort (0.4%, P < .001) but similar to that in Cancer Cohort (15%, P = .084). The incidence of sequelae in Cancer COVID-19 Cohort (23%, 26/114) is similar to that in COVID-19 Cohort (30%, 130/432, P = .13). The 1-year all-cause mortality was high among patients with hematologic malignancies (59%), followed by those who have nasopharyngeal, brain, and skin tumors (45%), digestive system neoplasm (43%), and lung cancers (32%). The rate was moderate among patients with genitourinary (14%), female genital (13%), breast (11%), and thyroid tumors (0). COVID-19 patients with cancer showed a high rate of in-hospital mortality and 1-year all-cause mortality, but the 12-month all-cause post-discharge mortality rate in survival discharged cancer COVID-19 patients was similar to that in Cancer Cohort. Comparing to COVID-19 Cohort, risk stratification showed that hematologic, nasopharyngeal, brain, digestive system, and lung tumors were high risk (44% vs 9%, P < 0.001), while genitourinary, female genital, breast, and thyroid tumors had moderate risk (10% vs 9%, P = .85) in COVID-19 Cancer Cohort. Different tumor subtypes had different effects on COVID-19. But if cancer patients with COVID-19 manage to survive their COVID-19 infections, then long-term mortality appears to be similar to the cancer patients without COVID-19, and their long-term clinical sequelae were similar to the COVID-19 patients without cancer.

Glycoproteomics Analysis Reveals Differential Expression of Site-Specific Glycosylation in Human Milk Whey during Lactation.

Protein N-glycosylation in human milk whey plays a substantial role in infant health during postnatal development. Changes in site-specific glycans in milk whey reflect the needs of infants under different circumstances. However, the conventional glycoproteomics analysis of milk whey cannot reveal the changes in site-specific glycans because the attached glycans are typically enzymatically removed from the glycoproteins prior to analysis. In this study, N-glycoproteomics analysis of milk whey was performed without removing the attached glycans, and 330 and 327 intact glycopeptides were identified in colostrum and mature milk whey, respectively. Label-free quantification of site-specific glycans was achieved by analyzing the identified intact glycopeptides, which revealed 9 significantly upregulated site-specific glycans on 6 glycosites and 11 significantly downregulated site-specific glycans on 8 glycosites. Some interesting change trends in N-glycans attached to specific glycosites in human milk whey were observed. Bisecting GlcNAc was found attached to 11 glycosites on 8 glycoproteins in colostrum and mature milk. The dynamic changes in site-specific glycans revealed in this study provide insights into the role of protein N-glycosylation during infant development.

The Protective and Long-Lasting Effects of Human Milk Oligosaccharides on Cognition in Mammals.

Over the last few years, research indicated that Human Milk Oligosaccharides (HMOs) may serve to enhance cognition during development. HMOs hereby provide an exciting avenue in the understanding of the molecular mechanisms that contribute to cognitive development. Therefore, this review aims to summarize the reported observations regarding the effects of HMOs on memory and cognition in rats, mice and piglets. Our main findings illustrate that the administration of fucosylated (single or combined with Lacto-N-neoTetraose (LNnT) and other oligosaccharides) and sialylated HMOs results in marked improvements in spatial memory and an accelerated learning rate in operant tasks. Such beneficial effects of HMOs on cognition already become apparent during infancy, especially when the behavioural tasks are cognitively more demanding. When animals age, its effects become increasingly more apparent in simpler tasks as well. Furthermore, the combination of HMOs with other oligosaccharides yields different effects on memory performance as opposed to single HMO administration. In addition, an enhanced hippocampal long-term potentiation (LTP) response both at a young and at a mature age are reported as well. These results point towards the possibility that HMOs administered either in singular or combination forms have long-lasting, beneficial effects on memory and cognition in mammals.

Degradation of Proteins From Colostrum and Mature Milk From Chinese Mothers Using an in vitro Infant Digestion Model.

This study provided insights into the degradation of human milk proteins in an in vitro infant digestion model by comparing colostrum (week 1) and mature milk (week 4) of 7 Chinese mothers individually. In this study, we adapted the exiting INFOGEST in vitro model, to conditions representative to infants (0 to 3 month-old). The level of undigested proteins was analyzed by LC-MS/MS after gel-electrophoretic separation and in-gel digestion. The BCA protein assay showed that the total undigested milk protein content decreased from the start to the end of digestion with variations between mothers, especially in the gastric phase (25-80%). Undigested proteins could also still be found after the intestinal phase, ranging from 0.5 to 4.2% of initial protein content. Based on LC-MS/MS analysis, milk protein digestion varied between the mothers individually, especially during the gastric phase. No differences could be observed between protein digestion from colostrum and mature milk after the intestinal phase. The highest levels of proteins remaining after intestinal digestion can be linked to the group immune-active proteins, for all mothers. The level of protease inhibitors and total protein content in the milk did not correlate with the overall proteolysis during digestion. The results also showed that milk serum proteins partly remained after the gastric phase, with 33% remaining from colostrum and 37% remaining from mature milk. More than 40 milk serum proteins were detected after the intestinal phase. Some of the highly abundant milk serum proteins (lactoferrin, serum albumin, bile salt-activated lipase, immunoglobulins, α1-antichymotrypsin) were still partially present intact after the intestinal phase, for all mothers. Caseins were also not completely digested in the gastric phase, with 35% remaining from colostrum and 13% remaining from mature milk. Caseins, on the other hand, were almost completely digested after the intestinal phase. The complete degradation of caseins into peptides might be related to their structural features. Overall, this study showed that digestion differed for the various human milk proteins by adapting an in vitro digestion model to infant physiological conditions, with the main differences between digestion of the milk from individual mothers being observed after gastric digestion.

[Clinical and cytogenetic study in a child with de novo chromosome 9 abnormality].

This study aimed to analyze the clinical phenotype of chromosome 9p deletion or duplication and its relationship with karyotype. A patient, female, aged 6 months, visited the hospital due to motor developmental delay. Karyotype analysis identified abnormalities of chromosome 9 short arm, and high-throughput sequencing found 9p24.3-9p23 deletion and 9p23-9p13.1 duplication. Her parents had a normal karyotype. Karyotype analysis combined with high-throughput sequencing is of great significance for improving the efficiency of etiological diagnosis in children with motor developmental delay or multiple congenital deformities and mental retardation.

Low calcium diet increases 4T1 mammary tumor carcinoma cell burden and bone pathology in mice.

Breast cancer metastasizes to bone in the majority of patients with advanced disease. We investigated the effects of inadequate dietary calcium (Ca) on bone turnover, tumor growth, and bone response to tumor in tibia inoculated with 4T1 mammary carcinoma cells. Nine-month-old female Balb/c mice were placed on an adequate Ca (5 g/kg diet, n = 30) or low Ca (80 mg/kg diet, n = 31) diet for 14 days, then injected intratibially with 1,000 4T1 cells (transfected with luciferase for bioluminescence imaging), and sacrificed at 5, 10, or 21 days post-inoculation (n = 7-10 mice/group). Control mice (n = 6/group) were injected with carrier and sacrificed at 10 days post-inoculation. Tibiae with muscle intact were excised and evaluated by microcomputed tomography and histology. In vivo bioluminescent imaging revealed that 4T1 cells metastasized to lung. Therefore, lungs were removed for quantification of tumor. Mice fed low Ca exhibited higher bone turnover and higher tibial lesion scores than mice fed adequate Ca. Lesion severity, manifested as cortical osteolysis and periosteal woven bone formation, and tumor cell infiltration to muscle, increased with time, irrespective of diet. However, for most skeletal endpoints the rates of increase were greater in mice consuming low Ca compared to mice consuming adequate Ca. Infiltration of tumor cells into adjacent muscle, but not metastasis to lung, was also greater in mice consuming low Ca diet. The findings suggest that high bone turnover due to Ca insufficiency results in greater local mammary tumor cell growth, cortical osteolysis, woven bone formation, and invasion to muscle in mice.

Our unrequited love for natural ingredients.

Naturally sourced food ingredients have been the beneficiary of legal, regulatory and consumer preference as the result of a widely shared assumption of safety. However, the natural substances consumed in modernity may have little to do with the historically consumed part of the plant or even the plant itself. Further, our initial impression of a safe plant derivative may well be false as the result of the use of different growth conditions or, changes in harvesting and processing conditions that may have brought about a higher level of toxic constituents. Despite the variability of plant constituents, manufacturers' standards are set according to the content of commercially desirable properties, rather than presence of potentially toxic constituents. Why then, after all the potential reservations regarding naturals, is there such an enmity toward synthetic chemicals (including single chemical fermentation products), which have been tested in a systematic manner for potential toxic effects and whose composition is well known as the result of consistent manufacturing techniques and analytical controls? The authors will describe the paradigms used for natural products safety review and compare them with the safety criteria required for an "artificial" food ingredient.

A Comparison between Low- and High-Passage Strains of Human Cytomegalovirus.

To understand how human cytomegalovirus (HCMV) might change and evolve after reactivation, it is very important to understand how the nucleotide sequence of cultured HCMV changes after in vitro passaging in cell culture, and how these changes affect the genome of HCMV and the consequent variation in amino acid sequence. Strain JHC of HCMV was propagated in vitro for more than 40 passages and its biological and genetic changes were monitored. For each passage, real-time PCR was performed in order to determine the genome copy number, and a plaque assay was employed to get virus infection titers. The infectious virus titers gradually increased with passaging in cell culture, whereas the number of virus genome copies remained relatively unchanged. A linear correlation was observed between the passage number and the log10 infectious virus titer per virus genome copy number. To understand the genetic basis underlying the increase in HCMV infectivity with increasing passage, the whole-genome DNA sequence of the high-passage strain was determined and compared with the genome sequence of the low-passage strain. Out of 100 mutations found in the high-passage strain, only two were located in an open reading frame. A G-T substitution in the RL13 gene resulted in a nonsense mutation and caused an early stop. A G-A substitution in the UL122 gene generated an S-F nonsynonymous mutation. The mutations in the RL13 and UL122 genes might be related to the increase in virus infectivity, although the role of the mutations found in noncoding regions could not be excluded.

Effects of letrozole on breast cancer micro-metastatic tumor growth in bone and lung in mice inoculated with murine 4T1 cells.

Breast cancer (BC) is the leading cancer in women worldwide. Metastasis occurs in stage IV BC with bone and lung being common metastatic sites. Here we evaluate the effects of the aromatase inhibitor letrozole on BC micro-metastatic tumor growth in bone and lung metastasis in intact and ovariectomized (OVX) mice with murine estrogen receptor negative (ER-) BC cells inoculated in tibia. Forty-eight BALB/c mice were randomly assigned to one of four groups: OVX, OVX + Letrozole, Intact, and Intact + Letrozole, and injected with 4T1 cells intra-tibially. Letrozole was subcutaneously injected daily for 23 days at a dose of 1.75 µg/g body weight. Tumor progression was monitored by bioluminescence imaging (BLI). Following necropsy, inoculated tibiae were scanned via µCT and bone response to tumor was scored from 0 (no ectopic mineralization/osteolysis) to 5 (extensive ectopic mineralization/osteolysis). OVX mice had higher tibial pathology scores indicative of more extensive bone destruction than intact mice, irrespective of letrozole treatment. Letrozole decreased serum estradiol levels and reduced lung surface tumor numbers in intact animals. Furthermore, mice receiving letrozole had significantly fewer tumor colonies and fewer proliferative cells in the lung than OVX and intact controls based on H&E and Ki-67 staining, respectively. In conclusion, BC-inoculated OVX animals had higher tibia pathology scores than BC-inoculated intact animals and letrozole reduced BC metastases to lungs. These findings suggest that, by lowering systemic estrogen level and/or by interacting with the host organ, the aromatase inhibitor letrozole has the potential to reduce ER- BC metastasis to lung.

Unusual Mott transition in multiferroic PbCrO3.

The Mott insulator in correlated electron systems arises from classical Coulomb repulsion between carriers to provide a powerful force for electron localization. Turning such an insulator into a metal, the so-called Mott transition, is commonly achieved by "bandwidth" control or "band filling." However, both mechanisms deviate from the original concept of Mott, which attributes such a transition to the screening of Coulomb potential and associated lattice contraction. Here, we report a pressure-induced isostructural Mott transition in cubic perovskite PbCrO3. At the transition pressure of ∼3 GPa, PbCrO3 exhibits significant collapse in both lattice volume and Coulomb potential. Concurrent with the collapse, it transforms from a hybrid multiferroic insulator to a metal. For the first time to our knowledge, these findings validate the scenario conceived by Mott. Close to the Mott criticality at ∼300 K, fluctuations of the lattice and charge give rise to elastic anomalies and Laudau critical behaviors resembling the classic liquid-gas transition. The anomalously large lattice volume and Coulomb potential in the low-pressure insulating phase are largely associated with the ferroelectric distortion, which is substantially suppressed at high pressures, leading to the first-order phase transition without symmetry breaking.

Dietary soy isoflavones increase metastasis to lungs in an experimental model of breast cancer with bone micro-tumors.

Bone is one of the most common sites for metastasis in breast cancer (BC). Micro-metastasis in bone marrow was detected in 30% of patients with stage I, II, or III BC at primary surgery and is a strong indicator of poor prognosis. The role dietary soy isoflavones play in BC with bone micro-metastasis is unclear. In this study, we examined the effects of genistein, daidzein, (-)-equol or a mixture of soy isoflavones on BC with bone micro-metastasis using an experimental model of murine mammary cancer 4T1 cells engineered with luciferase. A small number (1000) of 4T1 cells were injected into the tibia of female Balb/c mice to establish micro-tumors in bone. Soy isoflavones were supplemented in the AIN-93G diet at 750 mg/kg and were provided to mice from 3 weeks before to 3 weeks after cell injection. Bioluminescent imaging was conducted on day 2 (D2), D6, D8, D16 and D20 post cell injection and the results indicated dietary soy isoflavones enhanced the growth of bone micro-tumors on D8. Furthermore, dietary soy isoflavones stimulated metastatic tumor formation in lungs and increased Ki-67 protein expression in these metastasized tumors. In vitro, soy isoflavones (<10 µM) had limited effects on the growth, motility or invasion of 4T1 cells. Thus, the in vivo stimulatory effect could be likely due to systemic effects between the host, 4T1 tumors and soy isoflavones. In conclusion, soy isoflavones stimulate BC with bone micro-metastasis in mice and further investigations are needed regarding their consumption by BC survivors.

Selective Delivery of an Anticancer Drug with Aptamer-Functionalized Liposomes to Breast Cancer Cells in Vitro and in Vivo.

Selective targeting of cancer cells is a critical step in cancer diagnosis and therapy. To address this need, DNA aptamers have attracted significant attention as possible targeting ligands. However, while their use in targeting cancer cells in vitro has been reported, their effectiveness has rarely been established in vivo. Here we report the development of a liposomal drug delivery system for targeted anticancer chemotherapy. Liposomes were prepared containing doxorubicin as a payload, and functionalized with AS1411, a DNA aptamer with strong binding affinity for nucleolin. AS1411 aptamer-functionalized liposomes increased cellular internalization and cytotoxicity to MCF-7 breast cancer cells as compared to non-targeting liposomes. Furthermore, targeted liposomal doxorubicin improved antitumor efficacy against xenograft MCF-7 breast tumors in athymic nude mice, attributable to their enhanced tumor tissue penetration. This study suggests that AS1411 aptamer-functionalized liposomes can recognize nucleolin overexpressed on MCF-7 cell surface, and therefore enable drug delivery with high specificity and selectivity.