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1.
Investigations of the fine-scale structure in the compact nucleus of the radio source 3C 84 in NGC 1275 (New General Catalogue number) are reported. Structural monitoring observations beginning as early as 1976, and continuing to the present, revealed subluminal motions in a jet-like relatively diffuse region extending away from a flat-spectrum core. A counterjet feature was discovered in 1993, and very recent nearly simultaneous studies have detected the same feature at five frequencies ranging from 5 to 43 GHz. The counterjet exhibits a strong low-frequency cutoff, giving this region of the source an inverted spectrum. The observations are consistent with a physical model in which the cutoff arises from free-free absorption in a volume that surrounds the core but obscures only the counterjet feature. If such a model is confirmed, very-long-baseline radio interferometry observations can then be used to probe the accretion region, outside the radio jet, on parsec scales.  相似文献   

2.
Very-long-baseline radio interferometry images of the nuclear region of the nearby spiral galaxy M81 reveal the most compact galactic core outside the Galaxy of which the size has been determined: 700 x 300 astronomical units (AU). The observations exclude a starburst or supernova interpretation for the core. Instead they favor an active galactic nucleus. There is evidence for a northeastern jet bent by approximately 35 degrees over a length scale from 700 to 4000 AU. The jet is, on average, directed toward an extended emission region, probably a radio lobe, about 1 kiloparsec (kpc) away from the core. A corresponding emission region was found in the southwest at a distance of only 30 pc from the core. The observed jet is extremely stable and likely to be associated with a steady-state channel. There is no detectable motion along the jet beyond the nominal value of -60 +/- 60 km.s-1. The level of activities in the core region of M81 is intermediate between that of SgrA* and that of powerful radio galaxies and quasars.  相似文献   

3.

Background

Telehealth-supported clinical interventions may improve diabetes self-management. We explored the feasibility of stepwise self-titration of oral glucose-lowering medication guided by a mobile telephone-based telehealth platform for improving glycemic control in type 2 diabetes.

Methods

We recruited 14 type 2 diabetes patients to a one-year feasibility study with 1:1 randomization. Intervention group patients followed a stepwise treatment plan for titration of oral glucose-lowering medication with self-monitoring of glycemia using real-time graphical feedback on a mobile telephone and remote nurse monitoring using a Web-based tool. We carried out an interim analysis at 6 months.

Results

We screened 3476 type 2 diabetes patients; 94% of the ineligible did not meet the eligibility criteria for hemoglobin A1c (HbA1c) or current treatment. Mean (standard deviation) patient age at baseline was 58 (11) years, HbA1c was 65 (12) mmol/mol (8.1% [1.1%]), body mass index was 32.9 (6.4) kg/m2, median [interquartile range (IQR)] diabetes duration was 2.6 (0.6 to 4.7) years, and 10 (71%) were men. The median (IQR) change in HbA1c from baseline to six months was -10 (-21 to 3) mmol/mol (-0.9% [-1.9% to 0%]) in the intervention group and -5 (-13 to 6) mmol/mol (-0.5% [-1.2% to 0.6%]) in the control group. Six out of seven intervention group patients and four out of seven control group patients changed their oral glucose-lowering medication (p = .24).

Conclusions

Self-titration of oral glucose-lowering medication in type 2 diabetes with self-monitoring and remote monitoring of glycemia is feasible, and further studies using adapted recruitment strategies are required to evaluate whether it improves clinical outcomes.  相似文献   

4.
VLBI observations of the extremely gamma-bright blazar PKS 0528+134 at 8, 22, 43, and 86 GHz reveal a strongly bent one-sided-core jet structure with at least three moving and two apparently stationary jet components. At the highest observing frequencies the brightest and most compact jet component (the VLBI core) is unresolved with an upper limit to its size of approximately 50 microarcsec corresponding to approximately 0.2 parsec [H0 = 100 km.s-1.Mpc-1 (megaparsec-1), q0 = 0.5, where H0 is Hubble constant and q0 is the deceleration parameter]. Two 86-GHz VLBI observations performed in 1993.3 and 1994.0 reveal a new jet component emerging with superluminal speed from the core. Linear back-extrapolation of its motion yields strong evidence that the ejection of this component is related to an outburst in the millimeter regime and a preceding intense flare of the gamma-flux density observed in early 1993. This and the radio/optical "light curves" and VLBI data for two other sources (S5 0836+710 and 3C 454.3) suggest that the observed gamma-radiation might be Doppler-boosted and perhaps is closely related to the physical processes acting near the "base" of the highly relativistic jets observed in quasars.  相似文献   

5.

Background

This study examined whether mobile phone-based, one-way video messages about diabetes self-care improve hemoglobin A1c (A1C) and self-monitoring of blood glucose (SMBG).

Methods

This was a 1-year prospective randomized trial with two groups. The active intervention lasted 6 months. The study enrolled 65 people with A1C >8.0% who were established (>6 months) patients in the endocrinology clinics of the Walter Reed Health Care System. Participants were randomized to receive “usual care” or self-care video messages from their diabetes nurse practitioner. Video messages were sent daily to cell phones of study participants. Hemoglobin A1c and SMBG data were collected at 0, 3, 6, 9, and 12 months.

Results

Participants who received the messages had a larger rate of decline in A1C than people who received usual care (0.2% difference over 12 months, adjusting for covariates; p = .002 and p = .004 for the interaction between time and group and for the quadratic effect of time by group, respectively). Hemoglobin A1c decline was greatest among participants who received video messages and viewed >10 a month (0.6% difference over 12 months, adjusting for covariates; p < .001 for the interaction between time and group and the quadratic effect). Self-monitoring of blood glucose metrics were not related to the intervention.

Conclusions

A one-way intervention using mobile phone-based video messages about diabetes self-care can improve A1C. Engagement with the technology is an important predictor of its success. This intervention is simple to implement and sustain.  相似文献   

6.
The effects of physical treatment on induced fever in humans.   总被引:3,自引:0,他引:3  
PURPOSE: Initial treatments for fever include the amelioration of underlying causes and administration of antipyretic medications. However, patients who fail these treatments are often actively cooled, which may be counterproductive because decreasing skin temperature increases the thermoregulatory core target temperature. Cooling may also provoke metabolic and autonomic stress and thermal discomfort. SUBJECTS AND METHODS: We studied 9 subjects, each on 3 days. Fever was induced each day with 100,000 IU/kg of interleukin-2 administered intravenously (elapsed time zero). Randomly assigned treatments were 1) control (a cotton blanket), 2) cooling (forced air at 15 degrees C), or 3) self-adjust (forced-air warming adjusted to comfort). Treatments were maintained for 3 to 8 elapsed hours. RESULTS: Peak core temperatures (mean +/- SD) were 38.4 +/- 0.5 degrees C on the control day, 38.1 +/- 0.5 degrees C on the cooling day, and 38.5 +/- 0.4 degrees C on the self-adjust day. Integrated core temperatures were 6.0 +/- 1.6 degrees C x h on the control day, 5.7 +/- 2.2 degrees C x h on the cooling day, and 6.4 +/- 1.2 degrees C x h on the self-adjust day. Neither peak nor integrated core temperatures differed significantly on the 3 days. Shivering was common on the cooling day but otherwise rare. Oxygen consumption was normal on the control and self-adjust days but increased 35% to 40% during cooling (P = 0.0001). Mean arterial pressure and plasma norepinephrine and epinephrine concentrations were significantly greater during cooling (P <0.05). On a self-reported thermal comfort scale, the subjects were miserable during cooling and significantly more comfortable on the self-adjust than control day (P <0.05). CONCLUSION: We conclude that active cooling should be avoided in unsedated patients with moderate fever, because it does not reduce core temperature but does increase metabolic rate, activate the autonomic nervous system, and provoke thermal discomfort.  相似文献   

7.

Purpose

We pilot-tested a text message-based diabetes care program in an urban African-American population in which automated text messages were sent to participants with personalized medication, foot care, and appointment reminders and text messages were received from participants on adherence.

Methods

Eighteen patients participated in a 4-week pilot study. Baseline surveys collected data about demographics, historical cell phone usage, and adherence to core diabetes care measures. Exit interview surveys (using close-coded and open-ended questions) were administered to patients at the end of the program. A 1-month follow-up interview was conducted surveying patients on perceived self-efficacy. Wilcoxon signed-rank tests were used to compare baseline survey responses about self-management activities to those at the pilot''s end and at 1-month follow-up.

Results

Eighteen urban African-American participants completed the pilot study. The average age was 55 and the average number of years with diabetes was 8. Half the participants were initially uncomfortable with text messaging. Example messages include “Did you take your diabetes medications today” and “How many times did you check your feet for wounds this week?” Participants averaged 220 text messages with the system, responded to messages 80% of the time, and on average responded within 6 minutes. Participants strongly agreed that text messaging was easy to perform and helped with diabetes self-care. Missed medication doses decreased from 1.6 per week to 0.6 (p = .003). Patient confidence in diabetes self-management was significantly increased during and 1 month after the pilot (p = .002, p = .008).

Conclusions

Text messaging may be a feasible and useful approach to improve diabetes self-management in urban African Americans.  相似文献   

8.
OBJECTIVE: In rodents, adaptive thermogenesis in response to cold exposure and high-fat feeding is accomplished by the activation of the brown adipose tissue specific mitochondrial uncoupling protein, UCP1. The recently discovered human uncoupling protein 3 is a possible candidate for adaptive thermogenesis in humans. In the present study we examined the effect of mild cold exposure on the mRNA and protein expression of UCP3. SUBJECTS: Ten healthy male volunteers (age 24.4 +/- 1.6 y; height 1.83 +/- 0.02 m; weight 77.3 +/- 3.0 kg; percentage body fat 19 +/- 2). DESIGN: Subjects stayed twice in the respiration chamber for 60 h (20.00-8.00 h); once at 22 degrees C (72 degrees F), and once at 16 degrees C (61 degrees F). After leaving the respiration chamber, muscle biopsies were taken and RT-competitive-PCR and Western blotting was used to measure UCP3 mRNA and protein expression respectively. RESULTS: Twenty-four-hour energy expenditure was significantly increased at 16 degrees C compared to 22 degrees C (P<0.05). At 16 degrees C, UCP3T (4.6 +/- 1.0 vs 7.7 +/- 1.5 amol/microg RNA, P=0.07), UCP3L (2.0 +/- 0.5 vs 3.5 +/- 0.9 amol/microg RNA, P=0.1) and UCP3S (2.6 +/- 0.6 vs 4.2 +/- 0.7 amol/microg RNA, P=0.07) mRNA expression tended to be lower compared with at 22 degrees C, whereas UCP3 protein content was, on average, not different. However, the individual differences in UCP3 protein content (16-22 degrees C) correlated positively with the differences in 24 h energy expenditure (r=0.86, P<0.05). CONCLUSION: The present study suggests that UCP3 protein content is related to energy metabolism in humans and might help in the metabolic adaptation to cold exposure. However, the down-regulation of UCP3 mRNA with mild cold exposure suggests that prolonged cold exposure will lead to lower UCP3 protein content. What the function of such down-regulation of UCP3 could be is presently unknown.  相似文献   

9.
Administration of leptin during reduced nutrition improves reproductive activity in several monogastric species and reverses GH suppression in rodents. Whether leptin is a nutritional signal regulating neuroendocrine control of pituitary function in ruminant species is unclear. The present study examined the control of pulsatile LH and GH secretion in sheep. We determined whether exogenous leptin could prevent either the suppression of pulsatile LH secretion or the enhancement of GH secretion that occur during fasting. Recombinant human met-leptin (rhmet-leptin; 50 microg/kg BW; n = 8) or vehicle (n = 7) was administered s.c. every 8 h during a 78-h fast to estrogen-treated, castrated yearling males. LH and GH were measured in blood samples collected every 15 min for 6 h before fasting and during the last 6 h of fasting. Leptin was measured both by a universal leptin assay and by an assay specific for ovine leptin. During the fast, endogenous plasma leptin fell from 1.49 +/- 0.16 to 1.03 +/- 0.13 ng/ml. The average concentration of rhmet-leptin 8 h after leptin administration was 18.0 ng/ml. During fasting, plasma insulin, glucose, and insulin-like growth factor I levels declined, and nonesterified fatty acid concentrations increased similarly in vehicle-treated and leptin-treated animals. In vehicle-treated animals, LH pulse frequency declined markedly during fasting (5.6 +/- 0.5 vs. 1.1 +/- 0.5 pulses/6 h; fed vs. fasting; P < 0.0001). Leptin treatment prevented the fall in LH pulse frequency (5.0 +/- 0.4 vs. 4.9 +/- 0.4 pulses/6 h; P = 0.6). Neither fasting nor leptin administration altered GH pulse frequency. Fasting produced a modest increase in mean concentrations of circulating GH in control animals (2.4 +/- 0.5 vs. 3.4 +/- 0.6 ng/ml; P = 0.04), whereas there was a much greater increase in GH during leptin treatment (2.7 +/- 0.6 vs. 8.6 +/- 1.6 ng/ml; P = 0.0001). GH pulse amplitudes were also increased by fasting in control (P = 0.04) and leptin-treated sheep (P = 0.007). The finding that exogenous rhmet-leptin regulates LH and GH secretion in sheep indicates that this fat-derived hormone conveys information about nutrition to mechanisms controlling neuroendocrine function in ruminants.  相似文献   

10.
The effect of hyperthermia on the murine bone marrow stromal progenitor (fibroblast colony-forming unit, CFU-F) was evaluated and its ability to develop thermotolerance demonstrated. CFU-F were obtained from nucleated marrow of Balb/c mice and heated in vitro in alpha minimum essential medium plus 15% fetal bovine serum. Thermotolerance development was tested two ways. 1) The development of thermotolerance during prolonged hyperthermia was observed with a "step-up" heating protocol (i.e., cells were incubated at 41 degrees C and at regular intervals challenged with 15 min at 44 degrees C). 2) The development of thermotolerance at 37 degrees C after a short exposure to a high temperature (greater than or equal to 43 degrees C) was observed with a split treatment protocol that consisted of two 15-min treatments of 44 degrees C separated with time at 37 degrees C. The inverse of the slopes of the hyperthermia dose-response relationships (Do +/- SE) for CFU-F were 118 +/- 14, 53 +/- 7, 23 +/- 0.6, 11 +/- 0.3, 7 +/- 0.3, and 5 +/- 0.5 min for exposures of 41.5 degrees, 42 degrees, 42.5 degrees, 43 degrees, 43.5 degrees, and 44 degrees C, respectively. The plot of the slopes of the heat "dose-response" relationships versus the inverse of the absolute temperature (Arrhenius plot) yields a change in slope at approximately 43 degrees C, and the inactivation enthalpies (slopes above and below the inflection point at 43 degrees C) were 606 +/- 100 kJ/mol (145 +/- 24 kcal/mol) and 1372 +/- 29 kJ/mol (328 +/- 7 kcal/mol) above and below 43 degrees C, respectively. The maximum thermotolerance ratio (TTR, surviving fraction after maximum thermotolerance development to surviving fraction of normotolerant CFU-F) at 37 degrees C after an acute thermal exposure to 15 min at 44 degrees C occurred after 12 h, with a half time of 60 min and a TTR of 41. The maximum TTR during prolonged hyperthermia at 41 degrees C was 2.4 by approximately 50 min. These results show that CFU-F are as sensitive as committed hematopoietic precursors (e.g., granulocyte-macrophage colony-forming units, CFU-GM) to hyperthermia over a wide range of thermal exposures and are capable of thermotolerance development during prolonged hyperthermic exposures and at 37 degrees C after short exposures. We conclude that at least one of the stromal elements of normal marrow may be compromised during whole-body or regional clinical hyperthermia protocols.  相似文献   

11.
Somatosensory evoked potentials in moderate hyperthermia]   总被引:1,自引:0,他引:1  
The effects of moderate whole-body hyperthermia on the cervical and cortical somatosensory evoked potentials (SEP) were studied in healthy male subjects, aged 22-32 years. They were immersed in hot water and heated to a median rectal temperature of 39.0 degrees C. Serial SEPs to median nerve stimulation were recorded during cooling at intervals of 0.1 degrees C. The general wave form and the amplitudes did not systematically change. For a 1 degrees C drop there was a median latency increase of 2.6-3.7% in cervical and 1.5-7.4% in cortical SEP components. In individual cases significant latency delays of cervical N13 and cortical N20 could already be observed at differences of 0.2 degrees and 0.5 degrees respectively. All other components showed significant latency changes at temperature intervals of 0.6 to 0.8 degrees C.  相似文献   

12.

Background

Individuals with type 2 diabetes mellitus have impairments in early insulin release, resulting in increased postprandial glucose excursions and suboptimal glycemic control. Studies with Technosphere® Insulin (TI) indicate that it has rapid systemic absorption and a short duration of glucose-lowering activity, making it well suited for controlling postprandial glucose levels.

Methods

The goal of this phase 2b, prospective, multicenter, double-blind, placebo-controlled study was to characterize the dose response of four different doses (equivalent to 3.6, 7.3, 10.9, and 14.6 U subcutaneous regular human insulin) of prandial TI or Technosphere powder alone administered before each of three meals daily, in combination with insulin glargine over an 11-week treatment period, in patients with type 2 diabetes and suboptimal glycemic control.

Results

The study enrolled 227 patients. In all dose groups, TI demonstrated statistically significant dose-dependent reductions in hemoglobin A1c (HbA1c) versus baseline (-0.4, -0.5, -0.5, and -0.6 for 3.6, 7.3, 10.9, and 14.6 U equivalents, respectively; p < 0.05 in all groups), as well as versus placebo or Technosphere powder alone (-0.40, -0.67, -0.70, and -0.78 for 3.6, 7.3, 10.9, and 14.6 U equivalents, respectively; p < 0.04 in all groups). It reduced the postprandial maximum glucose concentration within each treatment group (statistically significant in all but the TI 3.6 U-equivalent group) and reduced the postprandial area under the glucose curve (statistically significant for the TI 10.9 and 14.6 U-equivalent groups) versus placebo. There were no cases of severe hypoglycemia, while mild/moderate hypoglycemia was observed most frequently in the highest dosage groups, as expected. Rates of cough were low and comparable among all groups. No clinically relevant changes in pulmonary function tests, body weight, or high-resolution computerized axial tomography and magnetic resonance imaging were observed.

Conclusions

This study demonstrated that, over 11 weeks, TI plus basal insulin glargine is well tolerated and results in dose-dependent reductions in postprandial glucose and HbA1c levels.  相似文献   

13.
The purpose of this study was to assess the stability of stored capsaicin solutions and the actual concentrations of prepared solutions. Capsaicin solutions ranging in concentration from 0.5 to 128 microM were mixed and analyzed using high performance liquid chromatography. Samples of varying concentrations were then stored under 4 environmental conditions: 4 degrees C and protected from light, room temperature (RT) exposed to light, RT protected from light, and -20 degrees C and protected from light. The concentrations were measured every other month for 1 year. Actual concentrations of freshly prepared solutions were on average 88.3% of predicted. For solutions stored at 4 degrees C, there was a decrease only in the lower concentrations (0.5, 1, and 2 microM) after 2 months (P=0.003). Solutions stored at RT exposed to light decreased in concentration after 6 months (P=0.020), and solutions stored at RT protected from light decreased in concentration after 4 months (P=0.026). The group stored at -20 degrees C decreased in concentration after 1 year (P=0.033). We conclude that the actual concentration of capsaicin solution is less than predicted, and solutions of 4 microM or higher concentration are stable for 1 year if stored at 4 degrees C protected from light.  相似文献   

14.

Introduction and objectives

Coronary heart disease is the second cause of death in Chilean women, with higher mortality among women, especially at younger ages. The objective was to analyze in-hospital case-fatality by sex and age in patients with acute myocardial infarction in Chile and to evaluate associated factors.

Methods

From the nationwide hospital admissions database and the GEMI registry (a multicenter registry), we selected all cases of acute myocardial infarction (code: I.21) that occurred between 2001 and 2007 in Chile. We estimated odds ratios for in-hospital case-fatality in women by age (crude and adjusted for clinical characteristics and treatment).

Results

In total, 49 287 cases of acute myocardial infarction were hospitalized, 31.3% of them women; 9278 patients were incorporated in the GEMI registry (27.1% women). In-hospital case-fatality was higher (P<.001) in women than men (national database, 20.4% vs 11.3%; GEMI, 14.2% vs 7.3%, irrespective of age. In-hospital case-fatality risk was higher in women aged<45 years: national odds ratio=2.3 (95% confidence interval, 1.5-3.3) and GEMI, odds ratio=2.7 (1.1-6.8). The estimated risk was lower in women aged 75 or more years in both databases, 1.3 (1.2-2.4) and 1.5 (1.2-1.9), respectively. Younger women less often received statins, odds ratio=0.7 (0.6-0.8); acetylsalicylic acid, odds ratio=0.4 (0.2-0.6); betablockers, odds ratio=0.8 (0.6-0.9), and thrombolytics, odds ratio=0.6 (0.5-0.8). An interaction was found between Killip class and sex. After adjusting for covariates, women aged<55 years with ST-segment elevation myocardial infarction and Killip class I-II, had the highest risk, odds ratio=4.3 (2.1-8.9).

Conclusions

In the context of a Latin American country, women aged<55 years with ST-segment elevation myocardial infarction and Killip class I-II had a higher risk of death. Known risk factors do not completely explain this excess of risk.Full English text available from:www.revespcardiol.org/en.  相似文献   

15.
The Doppler color jet area depicting a regurgitant or shunt lesion may be useful in estimating its severity. However, color jet area may be affected by technical factors. We studied the combined effects of Doppler angle, frame rate, and scanning direction on the Doppler color jet area of a free jet with 10-mL injection. Results: (1) Angle effects: color flow area was 11.7 +/- 2.0 cm2 at a Doppler angle of 20 degrees , and 2.3 +/- 1.2 cm2 at an angle of 60 degrees , when other parameters were kept constant (frame rate = 12 frames/sec, reverse scanning direction). (2) Frame rate effects: with other parameters kept constant (Doppler angle = 20 degrees , reverse scanning direction), color flow area was 11.7 +/- 2.0 cm2 at a rate of 12 frames/sec and 6.5 +/- 1.8 cm2 at 6 frames/sec. (3) Scanning direction effects: with other parameters kept constant (Doppler angle = 20 degrees , frame rate = 9 frames/sec), color flow area was 7.3 +/- 1.1 cm2 with scanning in the reverse direction, and 20.5 +/- 1.6 cm2 with scanning in the forward direction. (4) Combined effects: In our in vitro studies, the maximum color flow area was 20.5 +/- 1.6 cm2, and the minimum area was 1.5 +/- 0.2 cm2 (nearly twelve-fold). Conclusions: Doppler color jet area correlated inversely with Doppler angle (P less than 0.01) and directly with frame rate (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.

Background

Insulin requirements to maintain normoglycemia during glucocorticoid therapy and stress are often difficult to estimate. To simulate insulin resistance during stress, adults with type 1 diabetes mellitus (T1DM) were given a three-day course of prednisone.

Methods

Ten patients (7 women, 3 men) using continuous subcutaneous insulin infusion pumps wore the Medtronic Minimed CGMS® (Northridge, CA) device. Mean (standard deviation) age was 43.1 (14.9) years, body mass index 23.9 (4.7) kg/m2, hemoglobin A1c 6.8% (1.2%), and duration of diabetes 18.7 (10.8) years. Each patient wore the CGMS for one baseline day (day 1), followed by three days of self-administered prednisone (60 mg/dl; days 2–4), and one post-prednisone day (day 5).

Results

Analysis using Wilcoxon signed rank test (values are median [25th percentile, 75th percentile]) indicated a significant difference between day 1 and the mean of days on prednisone (days 2–4) for average glucose level (110.0 [81.0, 158.0] mg/dl vs 149.2 [137.7, 168.0] mg/dl; p = .022), area under the glucose curve and above the upper limit of 180 mg/dl per day (0.5 [0, 8.0] mg/dl·d vs 14.0 [7.7, 24.7] mg/dl·d; p = .002), and total daily insulin dose (TDI) , (0.5 [0.4, 0.6] U/kg·d vs 0.9 [0.8, 1.0] U/kg·d; p = .002). In addition, the TDI was significantly different for day 1 vs day 5 (0.5 [0.4, 0.6] U/kg·d vs 0.6 [0.5, 0.8] U/kg·d; p = .002). Basal rates and insulin boluses were increased by an average of 69% (range: 30–100%) six hours after the first prednisone dose and returned to baseline amounts on the evening of day 4.

Conclusions

For adults with T1DM, insulin requirements during prednisone induced insulin resistance may need to be increased by 70% or more to normalize blood glucose levels.  相似文献   

17.
BACKGROUND AND AIM: Usually, bacteria are cryopreserved for short-term storage at low and ultra-low temperatures. There are no reports as to whether Helicobacter pylori is a fragile bacteria when stored at low and ultra-low temperatures as compared with other intestinal bacteria. A study was done on seven H. pylori strains and other intestinal bacteria to compare different temperatures for storage of organisms in saline solution. METHODS: Seven H. pylori strains, specifically American Type Culture Collection (ATCC) strains 43504 and TN2GF4, and five strains isolated from the present patients were grown on a modified Skirrow's agar for H. pylori. Escherichia coli and Bacteroides distasonis, both representing isolates from the present patients, were grown on trypticase soy blood agar for E. coli, and EG agar for B. distasonis. Culture was for 4-5 days under microaerobic, aerobic and anaerobic conditions at 37 degrees C. Cells were harvested by scraping growth from the solid medium and into sterile saline. The cells were adjusted to concentrations of 109 viable cells/mL in saline and preserved at 4 degrees C, -20 degrees C, or -80 degrees C for 3 weeks before reculture under microaerobic, aerobic and anaerobic conditions at 37 degrees C for 7 days. After incubation, morphologically distinct colonies were counted, isolated, and identified by standard bacteriologic techniques. The H. pylori were morphologically analyzed by electronic microscopy before and after preservation. Mongolian gerbils were inoculated with the cryopreserved H. pylori to evaluate the bacterial infectivity. RESULTS: Six of the seven H. pylori strains failed to culture after being preserved at 4 degrees C, -20 degrees C, or -80 degrees C. Only ATCC 43504 could be cultured after freezing at -80 degrees C. The number of H. pylori ATCC 43504 before preservation was 9.0 +/- 0.5 (log10 no. organisms/mL) and decreased to 5.7 +/- 0.6 after preservation. Morphologically, all H. pylori except ATCC 43504 strains transformed from a bacillary to a coccoid form after preservation. In addition, none of the H. pylori strains could infect Mongolian gerbils after preservation. Escherichia coli and B. distasonis were recovered. Titers before and after 4 degrees C, -20 degrees C, and -80 degrees C, respectively, were 9.1 +/- 0.2, 8.9 +/- 0.5, 8.6 +/- 0.3, and 8.7 +/- 0.3 for E. coli and 9.1 +/- 0.4, 8.7 +/- 0.6, 8.6 +/- 0.5, and 8.8 +/- 0.3 for B. distasonis. CONCLUSIONS: Helicobacter pylori is a fragile bacteria for storage at low and ultra-low temperatures in comparison with other intestinal bacteria.  相似文献   

18.
INTRODUCTION: Weight gain appears to be unavoidable in patients with type 2 diabetes who are switched from oral agents to insulin therapy. Peripheral hyperinsulinism induced by the use of long-acting insulin may be the key to explain this adverse effect. AIM: The aim of this study was to investigate whether a regimen free of long-acting insulin can provide long-term glycaemic control without causing weight gain. PATIENTS AND METHODS: This is an uncontrolled, 1-year study comprising 58 patients with type 2 diabetes and secondary failure, age 30-75 years, BMI 25-35 kg/m(2), HbA1c > 7.5% and fasting C-peptide level > 0.3 mmol/l. All patients were treated with the GAME regimen, a combination of glimepiride administered at 20:00 hours for nocturnal glycaemic control, insulin aspart three times daily for meal-related glucose control and metformin. RESULTS: Seventy-one per cent of the patients were considered evaluable. HbA1c decreased from 10.0 +/- 0.3 to 7.4 +/- 0.1% (p < 0.001). Fifty-nine per cent reached HbA1c levels 相似文献   

19.

Objective:

The objective was to assess the relationship of skin advanced glycation endproducts (AGEs) between first-degree relatives estimated from skin fluorescence (SF) after adjustment for skin pigmentation.

Study design:

SF was excited by LEDs centered at 375, 405, and 420 nm from children with type 1 diabetes and their mothers. Data were adjusted to generate measures of skin intrinsic fluorescence (SIF) at the various excitation wavelengths, using 2 different pairs of correction coefficients for excitation (kx) and emission (km): kx = 0.5, km = 0.5 (not associated with skin pigmentation) and kx = 1.0, km = 0.0 (strongly associated with skin pigmentation). Pearson correlation analysis was performed, as well as a multiple variable analysis with maternal SIF adjusted for the effects of maternal age and race.

Results:

There were 50 matched pairs of children and their mothers. Children were 13.3 ± 3.7 years of age and there were 19 boys/31 girls and 15 black/35 white. Mothers were 41.8 ± 6.8 years of age. The age of mother and child was highly correlated, r = .64, P < .0001. In Pearson correlation analysis, child’s SIF (kx = 1.0, km = 0.0) the had strongest association with maternal SIF, while with SIF (kx = 0.5, km = 0.5) there was a trend for association. In the multiple variable model child SIF was associated with maternal SIF for all corrections and wavelengths but was stronger for kx = 1.0, km = 0.0.

Conclusion:

Even after adjustment for skin pigmentation and race, correlation of SIF between family members persists, suggesting that other genetic and/or environmental factors shared by parent and child may influence estimated skin AGEs.  相似文献   

20.
AIM: To determine the effect of cis -9, trans -11-conjugated linoleic acid (c9, t11-CLA) on the cell cycle of gastric cancer cells (SGC-7901) and its possible mechanism in inhibition cancer growth. METHODS: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/waf1) of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25, 50, 100 and 200 micromol.L(-1))of c 9, t 11-CLA for 24 and 48h, with a negative control (0.1% ethane). RESULTS: The cell growth and DNA synthesis of SGC-7901 cells were inhibited by c9, t11-CLA.SGC-7901 cells. Eight day after treatment with various concentrations of c9, t11-CLA mentioned above, the inhibition rates were 5.92%, 20.15%, 75.61% and 82.44%, respectively and inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 micromol.L, 24h) showed significantly less (3)H-TdR incorporation than that in the negative controls (P<0.05 and P<0.01). Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA (the expression rates were 7.2-3.0%, 24h and 9.1-0.9% at 48h, respectively), Cyclin A (11.0-2.3%, 24h and 8.5-0.5%,48h), B(1) (4.8-1.8% at 24h and 5.5-0.6% at 48h)and D(1) (3.6-1.4% at 24h and 3.7%-0 at 48h) as compared with those in the negative controls(the expressions of PCNA, Cyclin A, B(1) and D(1) were 6.5% at 24h and 9.0% at 48h, 4.2% at 24h and 5.1% at 48h, 9.5% at 24h and 6.0% at 48h,respectively)(P<0.01), whereas the expressions of P16(ink4a) and P21(cip/waf1), cyclin-dependent kinases inhibitors(CDKI), were increased. CONCLUSION: The cell growth and proliferation of SGC-7901 cell is inhibited by c9, t11-CLA via blocking the cell cycle, with reduced expressions of cyclin A,B(1) and D(1) and enhanced expressions of CDKI(P16(ink4a) and p21(cip/waf1)).  相似文献   

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