[Study on the reliability and validity of the Chinese Criteria of Health Scale for the elderly people]

Objective: To evaluate the reliability and validity of the Chinese Criteria of Health Scale for the elderly people. Methods: A cross-sectional study was performed among older adults of Meiyuan Community in Haidian District, Beijing and Nanwangkong Village in Qingzhou City,Shandong Province during July 2021. Using a cluster sampling method, totally 667 elderly people were investigated by face-to-face interview, using the scale which was formulated after two rounds of the Delphi method and pilot study. The overall scale includes physical health, mental health and social health subscales, including 9, 52 and 15 items, respectively. Four weeks after the survey, 56 elderly people were randomly selected and repeated the survey with the same method. The test-retest reliability, split-half reliability and internal consistency reliability of the scale were evaluated, and the validity was evaluated at the same time, including construct validity and content validity. Results: A total of 710 questionnaires were distributed and 667 valid questionnaires were obtained, with a total effective rate of 93.94%. The score of the overall scale was 79.79±16.22, the scores of the physical health, mental health, social health sub-scores were 41.64±9.76, 26.82±3.92 and 11.34±5.19, respectively. The scale had excellent reliability. In the test-retest reliability, the intraclass correlation coefficient (ICC) of the overall scale and each subscale were 0.766-0.861, and the weighted Kappa values were 0.762-0.817. The Spearman-Brown coefficient of the overall scale and each subscale in the split-half reliability were 0.722-0.855 (all P<0.001). The Cronbach's α coefficients of the overall scale of internal consistency reliability and each subscale were 0.748-0.899, and the Cronbach's α coefficients of each dimension were from 0.709 to 0.963(all P<0.001). At the same time, the scale had good construct validity and content validity. The correlation coefficients between the score of each dimension and its sub-scale were larger, from 0.641 to 0.873 (all P<0.05). The cumulative variance contribution rates of the scale and three subscales were all more than 50% of the approved standard. A total of 11 common factors were extracted, and all the load values of each item on the corresponding factors were ≥0.04. Conclusion: The Chinese Criteria of Health Scale for the elderly people has good validity and excellent reliability. It can be used as a basis for the scientific division of the health status of the elderly, the formulation of relevant policies by the government and the provision of appropriate health services for the elderly.

[The gender disparity and relevant factors of frailty in the elderly of communities in Beijing based on Fairlie decomposition analysis]

Objective: To analyze the gender disparity and relevant factors of frailty in the elderly of communities in Beijing. Methods: From November 2015 to January 2016, 1 557 participants aged 60 and older in four communities of Dongcheng district in Beijing were recruited by cluster sampling. The information of demographic characteristics, social support, economic status, health status, prevalence situation, cognitive function, emotion and comprehensive assessment of the elderly were collected by a self-made questionnaire. The frailty index (FI) model was used to evaluate the frailty of the elderly. Multivariate nonconditional logistic regression model and Fairlie decomposition method were applied to analyze the relevant factors and their contribution rate to the difference between males and females. Results: The age of subjects was (74.5±8.5) years old, ranging from 60-102 years old, among which 641 were males, accounting for 41.2%. The M (Q₁, Q₃) of FI was 0.09 (0.06, 0.14), among which the value in males was 0.08 (0.05, 0.13), lower than females [0.10 (0.06, 0.15)] (P<0.001).The frail proportion in female was 14.9% (137/916), higher than that of male [8.4% (54/641)] (P<0.001). Multivariate nonconditional logistic regression model analysis demonstrated that common relevant factors associated with frailty in older women and men include: age ≥80 years old, marital status as not married (unmarried, separated, divorced, or widowed), living alone increased the risk of frailty; participating in group activities ≥3 times/week and exercising regularly decreased the risk of frailty (all P<0.05). Fairlie decomposition method showed that the contribution rate of life style, family support, marital status and social support were 32.21%, 15.26%, 8.23% and 4.34%, respectively (all P<0.05). Conclusions: The frailty degree and frailty proportion of elderly women in communities in Beijing were higher than those of men of the same age. The frailty gender difference was related to lifestyle, family support, marital status and social support.

[Relationship between frailty status and risk of death in the elderly based on frailty index analysis]

Objective: To analyze the relationship between frailty status and the risk of death in the elderly based on the frailty index (FI). Methods: Data from a prospective cohort study conducted between 2005 and 2015 in elderly people of an urban community in Beijing were analyzed. The variables related to health and frailty status based on the 2005 baseline survey and death as outcome variables collected in 2015 were used. A FI model was used to evaluate the correlation between FI and mortality in the elderly people in different age groups was analyzed. Cox regression was applied to evaluate the influence of FI on the risk of death, and Kaplan-Meier curves was used to show the survival rate of different frailty levels in the elderly adults. Results: Of the 1 301 elderly people included in the analysis, 403 died during 2005-2015, with the 10-year mortality rate of 31.0%(403/1 301). The mortality rate of the elderly increased with the increase of FI, but, with the increase of FI value, the rate of mortality increased slowly. The limit value of FI causing death was around 0.70, indicating any new health problem might cause death at this value. Cox regression analysis showed that higher FI was associated with higher risk for death (HR=1.143, 95%CI: 1.034-1.248, P=0.000), and FI was more significantly associated with death than age (HR=1.143 vs. HR=1.048, t=5.827, P=0.000). With the increase of age, the effect of frailty on the risk of death decreased (HR=1.179 to HR=1.120). Kaplan-Meier curves showed that the survival rate of the elderly in all age groups decreased with the increase of frailty (Log-rank=317.812, 354.203, 247.258, all P=0.000). The survival time between different frailty levels in the elderly were significantly different, except for the elderly adults aged ≥80 years with severe frailty level (0.4≤FI<0.5, FI≥0.5, P=0.368). Conclusions: Compared with other evaluation tools of frailty, FI model can better reflect the frailty status of the elderly in communities in Beijing and has a high sensitivity in predicting adverse outcomes such as mortality. In the intervention of frailty in the elderly, focusing on relatively young elderly might be more effective in reducing the adverse outcomes caused by frailty.

[Relationship between fall and frailty index in elderly adults of urban community in Beijing]

Objective: To evaluate the frailty status and understand the relationship between the incidence of fall and frailty status in the elderly in Beijing. Methods: A cross-sectional study was conducted in old people aged ≥60 years in Longtan community of Dongcheng district in Beijing from November 2015 to January 2016. The information about any fall during the past year and frailty status of the elderly were collected with a standardized structured questionnaire in face-to-face interviews. The frailty status of elderly people was assessed with frailty index (FI) method. Logistic regression analysis was used to explore the relationship between fall and frailty status among the elderly. Results: Among 1 557 old people surveyed, the incidence of fall was 17.8% (277/1 557) during the past year. The incidence of fall in women (21.0%, 192/277) was statistically higher than that in men (13.3%, 85/277) (χ(2)=15.288, P=0.000). The median (quartile) value of FI of the elderly surveyed was 0.09 (0.08); and women had a higher FI median value than men [0.10 (0.08) versus 0.08 (0.07)](Z=5.376, P=0.000). The median FI value (quartile range) of 277 old people with history of fall in previous year was 0.12 (0.11), which was higher than the median FI value of 0.08 (0.07) of 1 280 old people without fall history (Z=7.501, P=0.000). Logistic regression analysis showed that higher FI value was associated with more risks for fall; and FI value showed the greatest impact on the incidence and frequency of fall (OR=1.093, 2.234) compared with other related factors of fall, such as age and gender. Conclusion: Frailty status has a greater impact on both incidence and frequency of fall compared with other factors in elderly people in Beijing; more attention should be paid to weak and old adults in the prevention of fall.

lncRNA HOXA11-AS is involved in fracture healing through regulating mir-124-3p

OBJECTIVE

Long noncoding RNAs (lncRNAs) have been reported to participate in many diseases. Fracture healing is one of these ordinary diseases. This study aims to identify how lncRNA HOXA11-AS affects the progression of fracture healing.

MATERIALS AND METHODS

RT-qPCR was performed to detect the level of HOXA11-AS. Moreover, function assays including cell growth assay and cell apoptosis assay were performed to explore how HOXA11-AS functions in fracture healing. Furthermore, the interaction between HOXA11-AS and mir-124-3p was studied by RT-qPCR, luciferase assay, and RNA immunoprecipitation assay. Rescue experiments were performed to verify the interaction between HOXA11-AS and mir-124-3p in vitro.

RESULTS

In the research, function assays revealed that HOXA11-AS overexpression inhibited cell proliferation, while HOXA11-AS knockdown promoted cell proliferation in vitro. Moreover, HOXA11-AS overexpression promoted cell apoptosis, while HOXA11-AS knockdown inhibited cell apoptosis in vitro. Furthermore, mechanism assays demonstrated that HOXA11-AS acts a ceRNA via sponging mir-124-3p. Rescue assay demonstrated that HOXA11-AS suppressed cell proliferation and promoted cell apoptosis via targeting mir-124-3p.

CONCLUSIONS

These results indicate that HOXA11-AS could inhibit cell proliferation and promote cell apoptosis of osteoblast via sponging mir-124-3p, which may offer a new vision for interpreting the mechanism of fracture healing.

[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.

Laser Cooling of a Micromechanical Membrane to the Quantum Backaction Limit

The radiation pressure of light can act to damp and cool the vibrational motion of a mechanical resonator, but even if the light field has no thermal component, shot noise still sets a limit on the minimum phonon occupation. In optomechanical sideband cooling in a cavity, the finite off-resonant Stokes scattering defined by the cavity linewidth combined with shot noise fluctuations dictates a quantum backaction limit, analogous to the Doppler limit of atomic laser cooling. In our work, we sideband cool a micromechanical membrane resonator to the quantum backaction limit. Monitoring the optical sidebands allows us to directly observe the mechanical object come to thermal equilibrium with the optical bath. This level of optomechanical coupling that overwhelms the intrinsic thermal decoherence was not reached in previous ground-state cooling demonstrations.

Solid-substrate fermentation ofKloeckera apiculata andCandida utilis on apple pomace to produce an improved stock-feed

Apple pomace was used in solid-substrate fermentation with the yeastsKloeckera apiculata orCandida utilis Y15. A total crude protein content of 7.5% (w/w) was achieved after 72 h for each yeast. The concentration of essential amino acids in the modified apple pomace was more than twice that in the control, enhancing its nutritive value as a stock-feed supplement. The fermentation of pomace as described can be used to reprocess this waste material into a useful value-added product for the agricultural sector.

Determination of the mode of action of enterolysin A, produced by Enterococcus faecalis B9510

AIM

The current study aimed to visualize the damage caused by enterolysin A to the cells of sensitive strains and to find out cleavage site within the peptidoglycan moiety of bacterial cell walls.

METHODS AND RESULTS

Enterolysin A produced by a local isolate, Enterococcus faecalis B9510 was found to rapidly kill cells of the sensitive strain Lactococcus lactis ssp. cremoris 2144 during 120 min of treatment as compared to the untreated control where no such effect was observed. Transmission electron microscopy of the enterolysin A-treated cells revealed leaking of the cytoplasmic contents ultimately resulting in complete lysis of cell walls. To find the cleavage site, purified cell walls of L. lactis ssp. cremoris 2144, Pediococcus pentosaceus 43201 and Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 were treated with enterolysin A, and liberated amino acids were derivatized for N and C terminals and analysed using thin layer chromatography on silica gel with isopropanol as solvent. The results showed that enterolysin A cleaves the peptide bonds at two locations within peptidoglycan subunits. The first location is between L-alanine and D-glutamic acid of the stem peptide and the other location is between L-lysine of the stem peptide and D-aspartic acid of the interpeptide bridge.

CONCLUSIONS

Enterolysin A cleaves the peptide bonds within the stem peptide as well as in the interpeptide bridge of Gram-positive bacterial cell walls. This gives a possible reason for the broad spectrum of enterolysin A activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report identifying the cleavage site of enterolysin A within the cell walls of sensitive bacteria. This will help in identifying potential applications for enterolysin A.

Control of material damping in high-Q membrane microresonators

We study the mechanical quality factors of bilayer aluminum-silicon-nitride membranes. By coating ultrahigh-Q Si(3)N(4) membranes with a more lossy metal, we can precisely measure the effect of material loss on Q's of tensioned resonator modes over a large range of frequencies. We develop a theoretical model that interprets our results and predicts the damping can be reduced significantly by patterning the metal film. Using such patterning, we fabricate Al-Si(3)N(4) membranes with ultrahigh Q at room temperature. Our work elucidates the role of material loss in the Q of membrane resonators and informs the design of hybrid mechanical oscillators for optical-electrical-mechanical quantum interfaces.

A device for feline head positioning and stabilization during magnetic resonance imaging

Minimization of head movement and reproduction of standard head positions are essential for reliable brain functional magnetic resonance imaging. Devices for stabilization and alignment of feline preparations are not available currently. We describe a system that involves minimal surgery, allows for both acute and chronic atraumatic positioning, and has the potential to be used for unanesthetized animals. The device uses non-metallic materials and stabilizes the head by means of an apparatus that fixes the head with nylon screws and dental cement in the frontal sinuses. Application of the head-stabilizing device decreases head movements by more than a factor of ten. Anatomical images show that this device provides 3 dimensional head placement at a precision comparable to that of a stereotactic frame, i.e. within 1 mm.

Mechanisms in regulating the release of serotonin from the perfused rat stomach

The mechanisms regulating the release of serotonin into the portal circulation as well as into the gastric lumen were studied in the isolated vascularly and luminally perfused rat stomach. Immunohistochemical study of the rat stomach showed that serotonin-containing enterochromaffin (EC) cells were densely packed in the antral mucosa, sparsely scattered in the corpus, and not found in the fundus. Such morphological findings suggest that serotonin detected in this study may have originated from antral EC cells. Luminal acidification stimulated the vascular release of serotonin but did not affect the luminal release of serotonin. The basal release of serotonin into the vasculature was 10 times higher than that into the gastric lumen at intragastric pH 2. The vascular release of serotonin is regulated by stimulation from cholinergic nicotinic mechanisms, whereas inhibitory neurotransmitters such as vasoactive intestinal peptide and NO are probably not involved. Somatostatin and peptide YY originating from endocrine cells may exert direct inhibitory effects, possibly via somatostatin and peptide YY receptors on the EC cells, and a cholinergic muscarinic mechanism may exert indirect effects on the vascular release of serotonin via the muscarinic receptor on the endocrine cells.

Fluid therapy of acute brain edema in children

The clinical experience with a new fluid therapy in children with acute brain edema complicated by infectious disease is reported. The clinical data of a retrospective group of 192 patients and a prospective study of 1,302 and 2,279 patients is summarized. One method of fluid therapy for children with acute brain edema is traditional; fluid intake is restricted to less than 1,200 mL/m(2) daily (60 mL/kg daily). Another method is the new fluid therapy regimen used in our prospective study, in which dehydration and fluid replenishment are individualized. On the first day the fluid intake of patients who survived varied from 40 to 208 mL/kg daily. The mortality rate in the two prospective groups was 19.66% in 1,302 patients and 17.2% in 2,279 patients, significantly lower than the 63.5% in the retrospective group (192 patients) (P <0.001). This result indicates that a wide range of fluid intake for children with acute brain edema is allowable during the first days of treatment. The appropriate dehydration and fluid replenishment should be individualized based on close observation of the patient's condition.

Immunohistochemical localization of tryptophan hydroxylase in the human and rat gastrointestinal tracts

Because few previous studies have shown the immunohistochemical localization of tryptophan 5-hydroxylase (TPH) in the gastrointestinal tract, we developed a specific antibody against TPH purified from mouse mastocytoma P-815 and stained human and rat gastrointestinal tracts. The specificity of the antibody was examined by Western blotting and by immunohistochemistry in brain sections. Human ileum and colon specimens, rat stomach, duodenum, jejunum, ileum and colon specimens, with and without colchicine treatment were prepared for immunohistochemistry. Immunoelectron microscopic double staining of TPH and serotonin/chromogranin A and immunofluorescence double staining of TPH and serotonin were performed to identify the cell types. Epithelial enterochromaffin (EC) cells, mast cells in the lamina propria and submucosa, and varicose fibers in the submucosa and muscle layer showed positive immunoreactivity in all segments examined from human and normal rat specimens. In colchicine-treated rat specimens, nerve cell bodies in the myenteric plexus were stained. Because the antibody does not cross react with tyrosine hydroxylase as defined in Western blotting or brain sections, these positive structures may contain TPH. The present results show evidence that EC cells, mast cells, and nerve cell bodies and fibers in the gastrointestinal tracts of both the human and the rat contain TPH and therefore may have the ability to synthesize serotonin from tryptophan.

[Multifactor analysis on proliferative retinopathy in elderly patients with type II diabetes]

To evaluate the importance of different risk factors and their mutual interactions in the occurrence of proliferative diabetic retinopathy (PDR) in the elderly patients with type II diabetes, an investigation was carried out on the relationship between PDR and various risk factors in 98 elderly cases of type II diabetes by way of stepwise regression analysis method. Results showed: (1) the average course of PDR was longer than that of diabetic patients without diabetic retinopathy (P < 0.01). Patients with PDR had higher values of BUN (P < 0.01), Cr(P < 0.05), GHbA1c(P < 0.01) and TC(P < 0.01) than those without retinopathy. Patients with PDR had higher coincidences of hypertension, coronary artery disease, proteinuria and urine microalbumin than those without retionpathy (P < 0.01) respectively, (2) multifactor analysis showed that BUN was one of the most important variables positively correlated with PDR, second to it in orders were the course of diabetes militus, GHbA1c, hypertention, proteinuria and urine microalbumin and TC.

CONCLUSION

To prevent the occurrence and progress of PDR in the elderly patients with type II diabetes, it is important not only to control blood sugar, but to control blood pressure and relieve renal damage.

Regression estimator in ranked set sampling

Ranked set sampling (RSS) utilizes inexpensive auxiliary information about the ranking of the units in a sample to provide a more precise estimator of the population mean of the variable of interest Y, which is either difficult or expensive to measure. However, the ranking may not be perfect in most situations. In this paper, we assume that the ranking is done on the basis of a concomitant variable X. Regression-type RSS estimators of the population mean of Y will be proposed by utilizing this concomitant variable X in both the ranking process of the units and the estimation process when the population mean of X is known. When X has unknown mean, double sampling will be used to obtain an estimate for the population mean of X. It is found that when X and Y jointly follow a bivariate normal distribution, our proposed RSS regression estimator is more efficient than RSS and simple random sampling (SRS) naive estimators unless the correlation between X and Y is low (/rho/ < 0.4). Moreover, it is always superior to the regression estimator under SRS for all rho. When normality does not hold, this approach could still perform reasonably well as long as the shape of the distribution of the concomitant variable X is only slightly departed from symmetry. For heavily skewed distributions, a remedial measure will be suggested. An example of estimating the mean plutonium concentration in surface soil on the Nevada Test Site, Nevada, U.S.A., will be considered.

Functional expression of the dihydrofolate reductase domain of Leishmania major dihydrofolate reductase-thymidylate synthase bifunctional protein

The dihydrofolate reductase (DHFR) domain of the bifunctional dihydrofolate reductase-thymidylate synthase from Leishmania major has been subcloned and expressed as a soluble protein in Escherichia coli strain PA414 harboring plasmid pLMDHFR. Homogeneous L. major DHFR was obtained by chromatography on methotrexate-Sepharose followed by DE52. The purified enzyme migrated as a single 25-kDa protein on SDS-PAGE. The native molecular weight was determined to be 26 kDa, indicating that the isolated domain is a monomer. N-terminal sequence analysis revealed that serine, the second amino acid in the coding sequence, was the N-terminal amino acid of the protein. The enzyme showed a pH optimum similar to that of the bifunctional protein. For purified DHFR, the Km values were <1.0 microM for H2folate and <1.0 microM for NADPH. The kcat of the most active DHFR preparation was 5 s-1. The Km and kcat values were similar to those of the bifunctional enzyme.

Effect of nimodipine on infectious brain edema in rabbits

AIM

To study the effect of nimodipine (Nim) on infectious brain edema (BE).

METHODS

An infectious BE model was induced by injection of Bordetella pertussis suspension (BPS) into right internal carotid artery in rabbits. Eighteen rabbits were randomly divided into 3 groups (n = 6). Group BE: BPS (0.6 mL.kg-1) was given; group NS: normal saline was given as control; group Nim: 10 min after injection of BPS, Nim, 10 micrograms.kg-1, was injected i.v. as a bolus followed by continuous infusion of 0.75 microgram.kg-1.min-1. All the rabbits were kept under observation for 4 h. Evans blue staining was assessed; water, calcium, calmodulin (Cal), and sodium contents were determined in the right brain.

RESULTS

Nim vs BE: water 82.2 +/- 1.0% vs 84.4 +/- 1.2 (P < 0.01); calcium 10.5 +/- 1.3 mmol.kg-1 dry tissue vs 17.5 +/- 1.4 (P < 0.01); Cal 15.9 +/- 1.8 mumol.kg-1 wet tissue vs 24.0 +/- 3.0 (P < 0.01); sodium 173 +/- 7 mmol.kg-1 dry tissue vs 275 +/- 38 (P < 0.05). No significant difference for Evans blue staining between the two groups.

CONCLUSION

Nim had beneficial effect on the infectious BE.

Trypanosoma brucei dihydrofolate reductase-thymidylate synthase: gene isolation and expression and characterization of the enzyme

The gene encoding the bifunctional dihydrofolate reductase (DHFR) and thymidylate synthase (TS) of Trypanosoma brucei brucei has been isolated and expressed in Escherichia coli, and the enzyme has been purified and characterized. The coding sequence of the DHFR-TS is 1581 nt, encoding a 527-amino-acid protein of 58,505 Da. The gene was expressed under control of the trc promoter in pKK233-2. The resulting expression plasmid conferred trimethoprim resistance to E. coli DH5 alpha and complemented the TS deficiency in chi 2913recA cells indicating the presence of active DHFR and TS. DHFR-TS was purified by methotrexate-Sepharose chromatography. In addition to the full-length enzyme, the purified enzyme contained 31 and 31.5-kDa forms of the enzyme that cross-reacted with anti-L. major DHFR-TS antibodies; one was truncated at the N- and C termini, and the other at only the C terminus. Despite the presence of sufficient TS for complementation, TS activity was not detectable in the crude extract or in the final purified enzyme preparation. Although the majority of the enzyme appears to be full length, it is possible that the TS domain has been degraded by one of more residues, which would inactivate the ability to synthesize thymidylate. Kinetic analysis of DHFR yielded kcat and Km values similar to those of related enzymes. The T. brucei DHFR has Ki values for antimicrobial antifolates pyrimethamine and trimethoprim which are significantly lower than the closely related T. cruzi or L. major DHFRs or than human DHFR.

[Effect of tetramethylhyrazine on proliferation of human fetal mesangial cells]

Tetramethylhyrazine (TMP) 0.6 and 1.2 mmol were added to human fetal mesangial cell (MC) cultures for 6 days, and the amounts of MC (cells/ml) were 37580 +/- 3475 and 27350 +/- 3418 respectively, significantly lower than that 71850 +/- 5108 in control (P < 0.05). The 3H-TdR incorporation by the MC with corresponding TMP were 1017 +/- 201 and 583 +/- 271, also significantly lower, than that 3575 +/- 306 in control (P < 0.01). After adding the TMP (1 mmol) to the cultures, the IL-6 bioactivity were 2118 +/- 215 that were markedly lower than those in controls (4128 +/- 351, P < 0.01). It revealed that the TMP inhibited the growth of MC and the mechanism of its inhibition might be due to that TMP could reduce the IL-6.

Synthetic and oxidative studies on 8-(arylamino)-2'-deoxyguanosine and -guanosine derivatives

Facile aerial oxidation is a general feature of guanine ribo- and 2'-deoxyribonucleosides that are substituted at the 8-position by an aminoaryl group. In previous work, it had been suggested that two of the major oxidation products are a pair of diastereomers having a spiro structure. These were presumed to be related by a chiral difference at the spiro carbon atom. The pattern of the oxidative process involves a contraction of the pyrimidine ring. It was thought to be analogous to that suggested by other investigators for the oxidation of uric acid, but for which no really definitive evidence had been presented. We have been able now to isolate in a crystalline state one of the diastereomers produced by the aerial oxidation of 8-phenylaminoguanosine under alkaline conditions. Analysis by X-ray diffraction has now confirmed the type of spiro structure promulgated previously. These findings also imply that spiro compounds are likely to be produced during the aerial oxidation of any 8-arylaminoguanine nucleoside or 2'-deoxynucleoside. In addition, this work adds considerable weight to the results of Poje and Sokolic-Maravic who proposed that a spiro intermediate is produced during the aerial oxidation of uric acid (12,13). However, they found this compound to be unstable to base, in contrast to the arylaminoguanine oxidation products. In the course of the above work we showed that the 8-arylamino derivatives of guanosine can be converted by the Barton deoxygenation method to the corresponding 2'-deoxyribonucleosides. This makes available a number of the latter compounds, which are not easily prepared by other methods.

Expression, purification, and characterization of thymidylate synthase from Lactococcus lactis

The thymidylate synthase (TS) gene from Lactococcus lactis has been highly expressed in Escherichia coli. The TS protein was purified by sequential chromatography on Q-Sepharose and phenyl-Sepharose. Six grams of cell pellet yielded 140 mg of homogeneous TS. TS is a highly conserved enzyme, and several of the conserved amino acid residues that have been implicated in catalytic function are altered in L. lactis TS. By use of a 3-dimensional homology model, we have predicted covariant changes that might compensate for these differences. With the large amounts of L. lactis TS now available, studies can be pursued to understand the structure-function relationships of this enzyme compared to other TSs and to confirm the presumed roles of the compensatory changes predicted in the homology model.

[Histological and immunohistochemical study and AgNOR analysis of smooth muscle tumors of the digestive tract]

Smooth muscle tumors of the esophagus (n = 29), stomach (n = 30), small intestine (n = 31) and large intestine (n = 12) were examined histologically and immunohistochemically for vimentin (Vim), desmin (Des), S100, fibronectin (FN) and cytokeratin (Cyt) and for nucleolar organizer regions (AgNOR). There were 49 cases of leiomyoma (LM), 51 cases of leiomyosarcoma (LS) and 2 cases of leiomyoblastoma(LB). Histologically, LS was characterized by cellular atypia, more cells in mitosis and invasion to adjacent normal tissue. No mitotic figure was observed in LM. AgNOR was more abundant in number in LS than LM (P < 0.001), but it had no direct relation to tumor size, number of cells in mitosis and patients' survival period. Immunohistochemical studies of Vim, Des, S100, FN and Cyt revealed that none of them was very helpful in the differential diagnosis of LM from LS.

Production of chymosin for the dairy industry by recombinant DNA technology

The increasing world production of cheese, coupled with a decline in the number of slaughtered calves, has stimulated a search for alternative sources of chymosin. This article briefly reviews microbial alternatives to chymosin and discusses chymosins produced using recombinant DNA technology. Recombinant chymosin represents one of the first successful applications of recombinant DNA technology in the food industry.

Effectiveness of enteric coated pancreatic enzymes given before meals in reducing steatorrhea in children with cystic fibrosis

In vitro data indicate that length of enzyme incubation with food critically affects enzyme dissolution and presumably effectiveness. This study compared the effectiveness of enteric coated (EC) pancreatic enzymes given before meals with those given during meals (15 minutes after beginning of meal) in reducing steatorrhea in well-nourished children with cystic fibrosis. Eight children (6 years 11 months old to 14 years 7 months old) were studied in the General Clinical Research Center at Indiana University Hospital, Indianapolis. A crossover study design randomly assigned enzymes before or during meals during two consecutive 7-day treatment periods for each child. No difference in fat excretion was documented for the total group when the children who took enzymes before meals were compared with those who took enzymes during meals. However, a stepwise multiple regression analysis of the difference (before minus during) in fat excretion on sex, age, enzyme number, and treatment order documented a positive correlation of age with fat excretion (r = .83). Mean fat excretion in younger children (less than 10 years old) decreased significantly when enzymes were given before meals (7.14 +/- 1.95%) rather than during meals (9.92 +/- 1.61%) (P = .004). The difference in fat excretion (mean = 2.78 +/- 0.55%, range = 1.4% to 4%) translates into a half to one full year's growth potential. Younger children with cystic fibrosis may benefit clinically from taking EC enzymes before meals.

In vitro expression of Lac-PTS and tagatose 1,6-bisphosphate aldolase genes from Lactococcus lactis subsp. cremoris plasmid pDI-21

A 4.4-kb EcoR1-EcoR1 DNA fragment from the Lactococcus lactis subsp. cremoris plasmid pDI-21 encoded the tagatose 1,6-bisphosphate (TBP) aldolase gene and the Lac-PTS genes. In vitro transcription-translation using Escherichia coli S30 extract showed the synthesis of 41,000-, 23,000- and 12,000-dalton proteins which correspond to the TBP-aldolase, Lac-PTS enzyme II, and factor III proteins respectively.

Genetic analysis of a lactococcal plasmid replicon

The sequence and genetic organization was determined of the 2508 bp lactococcal portion of pFX2, which was derived from a cryptic Lactococcus lactis subsp. lactis plasmid and used as the basis for construction of a series of lactococcal vectors. A lactococcal plasmid plus origin and two replication protein-coding regions (repA and repB) were located. RepA has a helix-turn-helix motif, a geometry typical of DNA-binding proteins. RepB shows a high degree of homology to the plasmid replication initiation proteins from other gram-positive bacteria and Mycoplasma. The transcribed inverted repeat sequence between repA and repB could form an attenuator to regulate pFX2 replication. Up-stream of the ori site, and in a region which was non-essential for replication, a 215 bp sequence identical to the staphylococcal plasmid pE194 and carrying the RSA site was identified. The genetic organization of this lactococcal plasmid replicon shares significant similarity with pE194 group plasmids.

A new model of global postischemic reperfusion in rabbit

An ideal model of global ischemia in rabbits has not yet been developed. The present study describes a new model of global postischemic reperfusion (GPIR) in the rabbit, characterized by lack of systemic hypotension. The experimental procedure involves reversible occlusion of the bilateral internal carotid arteries (ICA) and bilateral external carotid arteries (ECA) for 60 min combined with permanent ligation of bilateral vertebral arteries (VA). This grouping is called 6-artery occlusion (6AO). Sixty minutes after the occlusion, bilateral ICA and bilateral ECA were released for 120 min at which time the experiment was terminated. The results revealed severely depressed EEG activity; Water content of brain tissue increased to 80.33 +/- 1.20% (control 78.28 +/- 0.59%, p less than 0.01); K, Mg, and Zn decreased (p less than 0.05 or p less than 0.01), and were negatively correlated with tissue water content. Na increased (p less than 0.05) and correlated with water content of brain. No significant changes were observed in lipid peroxide (LPO) levels, but the activity of superoxide dismutase (SOD) of brain tissue decreased (p less than 0.01), and was negatively correlated with water content (r = -0.5808, p less than 0.05). These results were compared with those obtained with the model of 4-artery (bilateral common carotid arteries (CCA) and VA) occlusion (4AO) and suggested that the brain damage be more severe with 6AO than with 4AO.

Effectiveness and safety of small vs. large doses of enteric coated pancreatic enzymes in reducing steatorrhea in children with cystic fibrosis: a prospective randomized study

Among cystic fibrosis (CF) centers, usual doses of enteric coated (EC) pancreatic enzymes vary from one to six capsules per meal based upon arbitrary criteria for stool and growth patterns. Large doses of non-EC enzymes are associated with increased serum urate (SU) and urinary uric acid (UUA) but data are unavailable for EC enzymes. This study compared the effectiveness and safety of a relatively large dose (patient's usual dose) versus a small dose (1/4 usual dose) of EC enzymes in nine nourished children with CF, regarding decreasing fecal fat and stool nitrogen losses and maintaining normal SU and UUA concentrations. A crossover study design randomly assigned large or small doses to two consecutive 7 day treatment periods within each child. Large doses of EC enzymes reduced steatorrhea and increased SU and UUA. SU was normal with both treatments and UUA was normal, i.e., 17 of 18 values were between the 10th and 95th percentiles for healthy children eating a normal diet. When fat excretion was greater than 10% with small doses of EC enzymes, large doses resulted in reduced fat excretion and normal UUA. These data suggest that large doses of EC enzymes reduce steatorrhea and are safe in patients who have malabsorbtion with small doses.

Production of recombinant products in yeasts: a review

This paper reviews the use of yeasts to produce heterologous proteins via the development of transformation systems. The ability to genetically engineer yeast cells has many advantages over prokaryotic systems. Yeasts are already well established in fermentation procedures, are able to secrete glycosylated and modified proteins to render the proteins biologically active, and yeasts do not secrete toxic chemicals. With the techniques available it is possible to explore yeasts as hosts for the expression and secretion of commercially-useful proteins.

Construction of a family of lactococcal vectors for gene cloning and translational fusion

A family of stable lactococcal vectors have been constructed based on the pFX1 replicon using either the alpha fragment or the complete Escherichia coli lacZ gene as a selective marker. These vectors also incorporate multiple cloning sites and examples are given of their use for gene cloning and translational fusion studies in lactococci.

Molecular cloning and expression of a proteinase gene from Lactococcus lactis subsp. cremoris H2 and construction of a new lactococcal vector pFX1

The 6.5 kb HindIII DNA fragment of the Lactococcus lactis subsp. cremoris H2 plasmid pDI21 was cloned into Escherichia coli POP13 with lambda NM1149, and also directly into Lactococcus lactis subsp. lactis 4125 using a newly-constructed broad host-range vector pFX1. Proteinase was expressed in both transformed organisms. The proteinase resembles a PI type since it preferentially degraded beta-casein. The restriction map of the 6.5 kb proteinase gene fragment has minor differences from those of published plasmid proteinase genes. High-efficiency electroporation with pFX1 provides a direct approach for gene cloning in lactococci.

Synthesis of 1,N2-(1,3-propano)-2'-deoxyguanosine and incorporation into oligodeoxynucleotides: a model for exocyclic acrolein-DNA adducts

2'-Deoxyguanosine (3) and native DNA both give rise to exocyclic 1,N2-(1,3-propano)-2'-deoxyguanosine adducts 6 and 7 upon treatment with acrolein (1), a known mutagen, in vitro under physiological conditions. The use of synthetic deoxyoligonucleotides containing adduct 6 or 7 could shed light on the mechanism of the mutagenicity of 1 and on the nature of the structural perturbations present in DNA duplexes where they are present. Unfortunately, this is precluded by the instability of 6 and 7 to the conditions of automated DNA synthesis. We have prepared 1,N2-(1,3-propano)-2'-deoxyguanosine (PdG) (8) as a stable model for 6/7. The structure of 8 has been verified by magnetic resonance, ultraviolet spectroscopy, and mass spectrometry. This moiety has been incorporated into oligodeoxynucleotides via solid-state synthesis technology. Negative ion fast atom bombardment (FAB) mass spectrometry of the pentaoligodeoxynucleotide 5'-GT(PdG)CG-3' verified the identity and position of the modified base. The validity of 8 as a model system for the adduct pair 6/7 in structural and biological studies of DNA duplexes is discussed.

Integration of nutrition support into oncologic treatment protocols for high and low nutritional risk children with Wilms' tumor. A prospective randomized study

Benefits and risks of nutrition support were evaluated in 31 malnourished children with newly diagnosed Wilms' tumor managed according to the third National Wilms' Tumor Study protocol. Patients were classified at diagnosis as being at high nutritional risk (HNR, n = 19) or low nutritional risk (LNR, n = 12). Ten HNR patients were randomized to central parenteral nutrition (CPN) and nine HNR patients were randomized to peripheral parenteral nutrition (PPN) plus enteral nutrition (EN) for 4 weeks of initial intense treatment and EN (nutritional counseling, oral foods and supplements) thereafter. Thirteen HNR patients (seven CPN, six PPN) completed the protocol. Twelve LNR patients received EN; 11 Stage I malnourished patients were randomized to 10 or 26 weeks of chemotherapy. Dietary, anthropometric, and biochemical data were determined for HNR patients at weeks 0-4, 6, 13, 19, and 26 and for LNR patients at weeks 1, 2, 5, and 26. In HNR patients, adequate parenteral nutrition support reversed protein energy malnutrition (PEM), and prevented chemotherapy and radiotherapy delays due to granulocytopenia. CPN was superior to PPN in reversing PEM: energy intake, weight gain, and retinol binding protein were higher (P less than 0.05). LNR patients lost weight and fat reserves in the first 2 weeks of treatment; depletion persisted at week 5, and 25% had chemotherapy delays. Thereafter, EN reversed PEM in patients with both chemotherapy regimens. These data suggest that CPN is preferable during initial intense treatment for HNR patients, and that, although EN is ineffective in preventing depletion and treatment delays in the first 5 weeks of treatment for LNR patients, it is effective thereafter.

Lack of improved growth outcome related to nonnutritive sucking in very low birth weight premature infants fed a controlled nutrient intake: a randomized prospective study

The effect of nonnutritive sucking during gavage feeding on nutritional outcome and gastrointestinal transit time was evaluated in 18 premature appropriate for gestational age infants whose birth weights were less than or equal to 1,400 g and gestational ages were less than or equal to 30 weeks. Infants were randomized to a treatment (nonnutritive sucking infants received a pacifier for 30 minutes with each feeding, 12 times per day until they reached a weight of 1,500 g, eight times per day thereafter) or control (no pacifier) group. The nine nonnutritive sucking (five girls, four boys) and nine control (five girls, four boys) infants were treated for 14 days. Infants were without medical complications and were fed a single premature formula by intermittent gastric gavage at exactly 120 kcal/kg/d throughout the study period. Weight gain, linear growth, subscapular and triceps skinfold, and arm circumference accretions were assessed weekly. Serum proteins (albumin, prealbumin, retinol-binding protein, and transferrin) were measured weekly. Gastrointestinal transit times were measured weekly using carmine red markers. In contrast to previous studies, these data indicate no apparent effect of nonnutritive sucking on growth outcome, serum proteins, or gastrointestinal transit time in growing, very low birth weight infants when nutrient intake was controlled. In a subgroup of eight boys (four nonnutritive sucking, four control), energy and fat excretions were determined from 72-hour fecal collections and energy expenditure was estimated from six-hour cumulative heart rate measurements. Neither excretion of fat and calories nor estimated energy expenditure was affected significantly by nonnutritive sucking in this subgroup of baby boys. Fat excretion correlated well (r = .987) with energy excretion.

Heritability of bone mass: a longitudinal study in aging male twins

Midshaft radial bone mass was first measured from 1970 through 1972 by photon absorptiometry in 42 pairs of monozygotic (MZ) and 38 pairs of dizygotic (DZ) male Caucasian twins (age 44-55 years). The MZ intraclass correlation (rMZ) of .70 was significantly larger (P less than .05) than the DZ correlation (rDZ) of .45, providing evidence for genetic influences (Smith et al. 1973). Radial bone mass measurements repeated 16 years later (1986-87) on 25 of the MZ pairs and on 21 of the DZ pairs revealed an rMZ of .61 and an rDZ of .44, but the difference was not significant (P greater than .05). The twins had an average radial mass loss of 0.49%/year between the two examinations. The rMZ (.52) and rDZ (.49) values for the 16-year loss in radial mass were both significantly different from zero, but their similar size indicated that the correlations were due to nongenetic factors. In a search for the source of genetic influences on adult radial mass, heritability was estimated by the formula 2(rMZ - rDZ) for radial width and was found to be .66 and .76 (P less than .05) for examinations 1 and 2, respectively. An index of radial density (mass/width) was calculated, and the differences between rMZ and rDZ were not significant at either examination. The intraclass correlations (rMZ = .35; rDZ = .43) were both significant for the loss of bone density between examinations but provided no evidence for genetic influences, results similar to the findings for the loss of mass.(ABSTRACT TRUNCATED AT 250 WORDS)

Twin study: relationship between birth weight, zygosity, placentation, and pathologic placental changes

We examined the placentas of 182 like-sexed live-born twins: 73 placentas (40.1%) were monochorionic and 109 (59.9%) were dichorionic. All twin pairs with monochorionic placentas were monozygotic (MZ), but 28.9% of pairs with dichorionic placentas were MZ. Analysis of birth weights demonstrated that dichorionic and dizygotic (DZ) twins were heaviest, and suggested that the chorion status is a more important determinant of birth weight than zygosity. Vascular anastomoses were identified only in monochorionic placentas and occurred in 79.5% of cases. All placentas with deep anastomoses had superficial anastomoses. A higher proportion of velamentous and marginal insertions of the umbilical cord in monochorionic placentas (27.4%) compared to dichorionic placentas (13.8%) supports the belief that lateral placental growth is greatest in twin gestations in which the embryos are initially most closely apposed--The theory of trophotropism.

Vitamin E decreases superoxide anion production by polymorphonuclear leukocytes

Pharmacologic serum levels of vitamin E administered to low birth weight infants predispose them to infectious complications. We studied in vitro the effect of vitamin E, its vehicle and buffer (Krebs Ringers phosphate glucose) on the ability of human polymorphonuclear leukocytes (PMN) to produce superoxide anion, an oxygen radical important for bacterial killing. We found that superoxide anion production after a 5-min exposure to phorbol myristate acetate was significantly decreased in vitamin E-treated PMN (76 +/- 15 nM/10(7) PMN) compared to vehicle-treated PMN (289 +/- 109 nM/10(7) PMN). We also found that significantly decreased superoxide anion production was associated with 5.0 and 10.0 mg/dl but not with 3.5 mg/dl vitamin E. Our results support the hypothesis that pharmacologic concentrations of vitamin E depress PMN oxidative activity.

Alcohol effects on the percentage of beta waves in the electroencephalograms of twins

Electroencephalogram (EEG) recordings were made from 26 pairs of monozygotic (MZ) and 26 pairs of dizygotic (DZ) adult male twins, before and after alcohol ingestion. After a baseline EEG and a light breakfast, 1.2 ml/kg of ethanol was given orally over 15 min and the EEG repeated four times at hourly intervals. Alcohol caused a significant drop in the percentage of beta waves (14-30 cycles/sec) during the 1st hr. For the percentage of beta waves in 38 pairs of twins with complete data, MZ twin beta-wave intraclass correlations (RMZ) ranged between 0.85 and 0.91 before and after alcohol, but the DZ intraclass correlations (RDZ) started at 0.54 and fell to 0.05 at 2 hr after alcohol before recovering to baseline levels. These correlations resulted in heritability estimates [2(RMZ-RDZ)] of 0.68 at baseline and 1.73 at 2 hr. A heritability of 1.43 was found for the 1st hr drop in percentage of beta waves (RMZ = 0.78, RDZ = 0.06). These unrealistically high heritabilities, due to RDZ's approaching 0.0, suggest a failure of assumptions in the linear twin model that was used. Also, these findings are similar to, but more exaggerated than, findings in resting EEG's and visually evoked EEG potentials of twins and are compatible with the influence of gene interactions.

Free fatty acid and triglyceride levels in neonates receiving triple mix hyperalimentation

Total nutrient admixture (TNA) combines amino acids, lipids, and glucose in a single bottle for continuous parenteral use. This cost-effective and easily administered solution is now available for use in neonates. The present study was performed to assess the metabolism of fat administered as TNA in sick neonates as reflected by serum free fatty acid (FFA) and triglyceride (TG) levels. During a 6-month period, TG and FFA levels were monitored in all infants receiving TNA. Levels were measured within 24 hours of a change in lipid dose and then weekly when maximum intake (about 2 g/kg/day) was achieved. Sixty-nine TG and 58 FFA levels were obtained from 42 neonates who at the time of sampling were receiving 2 g/kg/day or more of parenteral lipid. Ninety-one percent of TG levels were less than or equal to 200 mg/dL. Ninety-six percent of FFA levels were less than or equal to 2000 mumol/L. A weak but statistically significant correlation was noted between TG and FFA levels with a correlation coefficient of 0.54. In conclusion, although the range of FFA and TG levels obtained from sick neonates on TNA therapy is relatively wide, these levels are comparable to those reported in the literature for infants receiving standard intravenous lipid infusions.

Comparison of purified indium-111 granulocytes and indium-111 mixed leukocytes for imaging of infections

Several methods have been proposed for the separation and labeling of white blood cells for the diagnosis of suspected infection. We retrospectively compared 105 patients imaged with 111In purified granulocytes (GRAN) to 106 patients imaged with 111In mixed leukocytes (MIX). We found that in acute infection the sensitivity of GRAN and MIX were both high and not statistically different. In chronic infections the sensitivities were lower than for acute infections. Again, there was no significant difference between GRAN and MIX with the borderline significant exception of MIX being superior to GRAN in chronic soft tissue infections (p = 0.06). We then had independent observers blindly grade the degree of lesion visualization. We found that delayed images visualized the lesions better than early images (p = 0.0001) and acute infection was better visualized than chronic infection (p = 0.03). We concluded that, in routine clinical practice, MIX is probably the agent of choice for three reasons: (a) easier preparation, (b) comparable sensitivity in acute infection and, (c) borderline superior sensitivity in chronic infection.

Lung mechanics and neuromuscular output during CO2 inhalation after airway anesthesia

Airway anesthesia with aerosolized lidocaine has been associated with an increase in minute ventilation (VE) during CO2 inhalation. The increase in VE may be due to increased neuromuscular output or decreased mechanical load on breathing. To evaluate this we measured VE, breathing pattern, mouth occlusion pressure, and lung mechanics in 20 normal subjects during room-air breathing and then inhalation of 6% CO2-94% O2, before and after airway anesthesia. Measurements of lung mechanics included whole-lung resistance, dynamic and static compliance, and functional residual capacity. Airway anesthesia had no detectable effect on any measurements during room-air breathing. During CO2 inhalation, airway anesthesia produced increases in VE and mean inspiratory flow rate (VT/TI) and more negative inspiratory pleural pressure but had no detectable effect on lung mechanics or mouth occlusion pressure. Pleural pressure was more negative during the latter 25% of inspiration. We concluded that airway receptors accessible to airway anesthesia play a role in determining neuromuscular output during CO2 inhalation.