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HardwareX Apr 2021Many routines in biological experiments require the precise handling of liquid volumes in the range of microliters up to liters. In this paper, we describe a new...
Many routines in biological experiments require the precise handling of liquid volumes in the range of microliters up to liters. In this paper, we describe a new wireless controller that is adapted to liquid manipulation tasks, in particular when combined with the proposed 3D-printed pumps. It can be built from widely available electronic components and managed with open-source software. The use of peristaltic pumps enables to move volumes from milliliters to liters with a relative error below 1% or a syringe pump capable of injecting volumes in the range of milliliters with microliter accuracy. The system is remotely controllable over WiFi and easily automated using the MQTT communication protocol. The programming of the microcontroller is performed on the Arduino IDE. The WiFi settings and the calibration value can be easily modified, stored and exported in the form of a JSON file to create a user friendly, plug and play and easily scalable device. Additional sensors or actuators can be added, allowing the system to adapt to various usages. Finally, in addition to its low manufacturing cost and its capability to fit a large variety of tasks involving liquid handling, our system has been specifically designed for research environments where adaptability and repeatability of experiments is essential.
PubMed: 35601242
DOI: 10.1016/j.ohx.2021.e00199 -
The New England Journal of Medicine Feb 2002The adipocyte hormone leptin is important in regulating energy homeostasis. Since severe lipodystrophy is associated with leptin deficiency, insulin resistance,... (Clinical Trial)
Clinical Trial
BACKGROUND
The adipocyte hormone leptin is important in regulating energy homeostasis. Since severe lipodystrophy is associated with leptin deficiency, insulin resistance, hypertriglyceridemia, and hepatic steatosis, we assessed whether leptin replacement would ameliorate this condition.
METHODS
Nine female patients (age range, 15 to 42 years; eight with diabetes mellitus) who had lipodystrophy and serum leptin levels of less than 4 ng per milliliter (0.32 nmol per milliliter) received recombinant methionyl human leptin (recombinant leptin). Recombinant leptin was administered subcutaneously twice a day for four months at escalating doses to achieve low, intermediate, and high physiologic replacement levels of leptin.
RESULTS
During treatment with recombinant leptin, the serum leptin level increased from a mean (+/- SE) of 1.3 +/- 0.3 ng per milliliter to 11.1 +/- 2.5 ng per milliliter (0.1 +/- 0.02 to 0.9 +/- 0.2 nmol per milliliter). The absolute decrease in the glycosylated hemoglobin value was 1.9 percent (95 percent confidence interval, 1.1 to 2.7 percent; P=0.001) in the eight patients with diabetes. Four months of therapy decreased average triglyceride levels by 60 percent (95 percent confidence interval, 43 to 77 percent; P<0.001) and liver volume by an average of 28 percent (95 percent confidence interval, 20 to 36 percent; P=0.002) in all nine patients and led to the discontinuation of or a large reduction in antidiabetes therapy. Self-reported daily caloric intake and the measured resting metabolic rate also decreased significantly with therapy. Overall, recombinant leptin therapy was well tolerated.
CONCLUSIONS
Leptin-replacement therapy improved glycemic control and decreased triglyceride levels in patients with lipodystrophy and leptin deficiency. Leptin deficiency contributes to the insulin resistance and other metabolic abnormalities associated with severe lipodystrophy.
Topics: Adolescent; Adult; Basal Metabolism; Blood Glucose; Diabetes Complications; Diabetes Mellitus; Energy Intake; Female; Glycated Hemoglobin; Humans; Injections, Subcutaneous; Insulin Resistance; Leptin; Lipodystrophy; Liver; Liver Function Tests; Prospective Studies; Triglycerides
PubMed: 11856796
DOI: 10.1056/NEJMoa012437 -
Open Access Macedonian Journal of... Jul 2018To assess the antibacterial competence of 650 nm diode laser, Methylene Blue (MB) and Silver Nano-Particles (Ag NPs) on Streptococcus mutans in biofilm-induced caries...
AIM
To assess the antibacterial competence of 650 nm diode laser, Methylene Blue (MB) and Silver Nano-Particles (Ag NPs) on Streptococcus mutans in biofilm-induced caries models.
MATERIAL AND METHODS
One hundred eighty specimens were prepared and equally divided into 6 groups. One group was untreated (control), and the others were subjected to either MB, laser, Ag NPs, the combination of MB and Laser or MB, laser and Ag NPs.
RESULTS
Comparison of the log10 mean Colony Forming Units per millilitre (CFU/ml) values of each of the treated 5 groups and the control group was found statistically significant (P-value < 0.05). The combination of MB, laser and Ag NPs recorded the greatest reduction (95.28%). MB alone represented the least capable (74.09%). The efficiency differences among the Ag NPs treated group; the Laser treated group and the combined MB/Laser treated group were found statistically insignificant.
CONCLUSION
The combination of MB, 650 nm diode laser and Ag NPs may be among the highly effective modern antimicrobial therapeutics in dentistry.
PubMed: 30087739
DOI: 10.3889/oamjms.2018.241 -
The New England Journal of Medicine Jul 2010The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for...
BACKGROUND
The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level.
METHODS
We surveyed a random population sample of 3369 men between the ages of 40 and 79 years at eight European centers. Using questionnaires, we collected data with regard to the subjects' general, sexual, physical, and psychological health. Levels of total testosterone were measured in morning blood samples by mass spectrometry, and free testosterone levels were calculated with the use of Vermeulen's formula. Data were randomly split into separate training and validation sets for confirmatory analyses.
RESULTS
In the training set, symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level. Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels (ranges, 8.0 to 13.0 nmol per liter [2.3 to 3.7 ng per milliliter] for total testosterone and 160 to 280 pmol per liter [46 to 81 pg per milliliter] for free testosterone). However, only the three sexual symptoms had a syndromic association with decreased testosterone levels. An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed. These relationships were independently confirmed in the validation set, in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism.
CONCLUSIONS
Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter (3.2 ng per milliliter) and a free testosterone level of less than 220 pmol per liter (64 pg per milliliter).
Topics: Activities of Daily Living; Adult; Age of Onset; Aged; Depression; Erectile Dysfunction; Europe; Fatigue; Health Surveys; Humans; Hypogonadism; Libido; Logistic Models; Male; Middle Aged; Prevalence; Surveys and Questionnaires; Testosterone
PubMed: 20554979
DOI: 10.1056/NEJMoa0911101 -
The Journal of Clinical Endocrinology... Nov 2013Islet transplantation can improve metabolic control for type 1 diabetes (T1D), an effect anticipated to improve insulin sensitivity. However, current immunosuppression... (Clinical Trial)
Clinical Trial
CONTEXT
Islet transplantation can improve metabolic control for type 1 diabetes (T1D), an effect anticipated to improve insulin sensitivity. However, current immunosuppression regimens containing tacrolimus and sirolimus have been shown to induce insulin resistance in rodents.
OBJECTIVE
The objective of the study was to evaluate the effect of islet transplantation on insulin sensitivity in T1D using euglycemic clamps with the isotopic dilution method to distinguish between effects at the liver and skeletal muscle.
DESIGN, SETTING, AND PARTICIPANTS
Twelve T1D subjects underwent evaluation in the Clinical and Translational Research Center before and between 6 and 7 months after the transplant and were compared with normal control subjects.
INTERVENTION
The intervention included intrahepatic islet transplantation according to a Clinical Islet Transplantation Consortium protocol under low-dose tacrolimus and sirolimus immunosuppression.
MAIN OUTCOME MEASURES
Total body (M/Δinsulin), hepatic (1/endogenous glucose production ·basal insulin) and peripheral [(Rd - endogenous glucose production)/Δinsulin] insulin sensitivity assessed by hyperinsulinemic (1 mU·kg(-1)·min(-1)) euglycemic (∼90 mg/dL) clamps with 6,6-(2)H2-glucose tracer infusion were measured.
RESULTS
Glycosylated hemoglobin was reduced in the transplant recipients from 7.0% ± 0.3% to 5.6% ± 0.1% (P < .01). There were increases in total (0.11 ± 0.01 to 0.15 ± 0.02 dL/min·kg per microunit per milliliter), hepatic [2.3 ± 0.1 to 3.7 ± 0.4 × 10(2) ([milligrams per kilogram per minute](-1)·(microunits per milliliter)(-1))], and peripheral (0.08 ± 0.01 to 0.12 ± 0.02 dL/min·kg per microunit per milliliter) insulin sensitivity from before to after transplantation (P < .05 for all). All insulin sensitivity measures were less than normal in T1D before (P ≤ .05) and not different from normal after transplantation.
CONCLUSIONS
Islet transplantation results in improved insulin sensitivity mediated by effects at both the liver and skeletal muscle. Modern dosing of glucocorticoid-free immunosuppression with low-dose tacrolimus and sirolimus does not induce insulin resistance in this population.
Topics: Adult; Diabetes Mellitus, Type 1; Female; Glucose Clamp Technique; Glycated Hemoglobin; Graft Rejection; Humans; Immunosuppressive Agents; Insulin; Insulin Resistance; Islets of Langerhans Transplantation; Liver; Male; Middle Aged; Muscle, Skeletal; Sirolimus; Tacrolimus
PubMed: 24085506
DOI: 10.1210/jc.2013-1764 -
The New England Journal of Medicine Jul 1992Transplantation of pancreatic islets, rather than whole pancreas, has been introduced as a treatment for diabetes mellitus. We studied five patients ranging in age from...
BACKGROUND
Transplantation of pancreatic islets, rather than whole pancreas, has been introduced as a treatment for diabetes mellitus. We studied five patients ranging in age from 12 to 37 years who had severe chronic pancreatitis for which they underwent total pancreatectomy followed by isolation and hepatic transplantation of their own islets.
METHODS
All patients had remained insulin-independent for 1 to 7 1/2 years after transplantation. The numbers of islets transplanted ranged from 110,000 to 412,000. Islet function was assessed by measuring the plasma insulin responses to intravenous glucose and arginine and the plasma glucagon responses to hypoglycemia and arginine. In one patient, islet function was studied during catheterization of the hepatic vein, portal vein, and splenic artery and by analysis of a liver-biopsy specimen.
RESULTS
After transplantation, the mean (+/- SD) fasting plasma glucose concentration was 122 +/- 47 mg per deciliter (6.8 +/- 2.6 mmol per liter) and the hemoglobin A1c concentration was 6.0 +/- 0.8 percent in the five patients. The values were most abnormal--214 mg per deciliter (11.9 mmol per liter) and 7.3 percent, respectively--in the patient who received only 110,000 islets. The acute plasma insulin responses to glucose and to arginine in the five patients were 23 +/- 13 and 26 +/- 10 microU per milliliter (168 +/- 94 and 184 +/- 70 pmol per liter), respectively, as compared with 58 +/- 6 and 37 +/- 8 microU per milliliter (416 +/- 44 and 267 +/- 61 pmol per liter) in the normal subjects. The peak plasma glucagon responses to insulin and arginine were 21 +/- 4 and 65 +/- 36 pg per milliliter, respectively, as compared with 125 +/- 28 and 156 +/- 99 pg per milliliter in the normal subjects. All five patients had plasma epinephrine but not pancreatic polypeptide responses to hypoglycemia. The results of the hepatic-vein catheterization in one patient indicated that the transplanted islets released insulin and glucagon in response to arginine. Immunoperoxidase staining of this patient's liver-biopsy specimen showed that the islets contained insulin, glucagon, and somatostatin but not pancreatic polypeptide.
CONCLUSIONS
Intrahepatic transplantation of as few as 265,000 islets can result in the release of insulin and glucagon at appropriate times and in prolonged periods of insulin independence.
Topics: Adolescent; Adult; Arginine; Blood Glucose; Chronic Disease; Female; Glucagon; Glucose; Glycated Hemoglobin; Humans; Hypoglycemia; Insulin; Insulin Secretion; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Male; Pancreatectomy; Pancreatic Polypeptide; Pancreatitis; Transplantation, Autologous
PubMed: 1614463
DOI: 10.1056/NEJM199207233270402 -
JSES Open Access Oct 2017There is convincing evidence supporting the prophylactic use of intrawound vancomycin powder in spinal fusion surgery and mounting evidence in the arthroplasty...
BACKGROUND
There is convincing evidence supporting the prophylactic use of intrawound vancomycin powder in spinal fusion surgery and mounting evidence in the arthroplasty literature suggesting that it can reduce surgical site infections. As a result, a number of shoulder arthroplasty surgeons have adopted this practice, despite a paucity of evidence and the presence of a pathogen that is, for the most part, unique to this area of the body-. The purpose of this study was to evaluate the efficacy of vancomycin against planktonic in vitro, using time-dependent concentrations one would expect in vivo after intra-articular application.
METHODS
Intrawound vancomycin concentrations were interpolated and extrapolated from existing in vivo data. Planktonic was then subjected to a time-kill analysis during 96 hours. At each time point, the inoculum was centrifuged into pellet form and then reconstituted for serial drop counts onto blood agar plates. After anaerobic incubation, colony-forming units were counted, and log colony-forming units per milliliter were determined.
RESULTS
Early time points grew to confluence, and thus colony-forming units per milliliter were not calculated. However, at 12 hours of vancomycin treatment, distinct colonies were appreciated. Notably, there was a 3 × log reduction in colony-forming units per milliliter between 12 and 48 hours, denoting bactericidal activity. In addition, was completely eradicated after 3 days of treatment.
CONCLUSION
When administered in a fashion meant to simulate time-dependent in vivo intrawound concentrations, vancomycin exhibited bactericidal activity against . This may lend credence to the prophylactic use of vancomycin in shoulder surgery.
PubMed: 30675553
DOI: 10.1016/j.jses.2017.08.001 -
New Microbes and New Infections Sep 2020Multiple studies have established the contamination of hospital sinks and transmission to hospital personnel. Few studies have assessed the contamination and...
Multiple studies have established the contamination of hospital sinks and transmission to hospital personnel. Few studies have assessed the contamination and transmission of microorganisms from the faucets of operating bay scrub sinks to operating room (OR) personnel, a potential route of infection for patients. This study aimed to investigate if there was pathogenic contamination of scrub sinks and possible transmission of those pathogens to the hands of OR personnel after preoperative hand disinfection. Swabs were taken from the hands of 50 OR personnel and from the faucets of 24 scrubs sinks at two different hospital sites, and were cultured. Hands were swabbed after completing a surgical hand scrub. Results were reported in colony-forming units per millilitre. There was significant scrub sink contamination with primarily Gram-negative organisms, such as and . There was no overlap in bacterial species between the cultures from hands and scrub sinks. Cultures from the sinks and the hands of the OR personnel from one site had significantly higher bacterial growth compared with the other site (p < 0.0001 and p < 0.0118, respectively). The data showed significant contamination on the faucets of operating bay scrub sinks. However, there was no observed transmission of pathogens from the scrub sinks to OR personnel, shown by the lack of overlap in bacterial species. Routine hygienic maintenance of scrub sinks is recommended.
PubMed: 32995014
DOI: 10.1016/j.nmni.2020.100754 -
The New England Journal of Medicine Oct 2005We investigated the presence of osteopontin in pleural mesothelioma and determined serum osteopontin levels in three populations: subjects without cancer who were... (Comparative Study)
Comparative Study
BACKGROUND
We investigated the presence of osteopontin in pleural mesothelioma and determined serum osteopontin levels in three populations: subjects without cancer who were exposed to asbestos, subjects without cancer who were not exposed to asbestos, and patients with pleural mesothelioma who were exposed to asbestos.
METHODS
A group of 69 subjects with asbestos-related nonmalignant pulmonary disease were compared with 45 subjects without exposure to asbestos and 76 patients with surgically staged pleural mesothelioma. Tumor tissue was examined for osteopontin by immunohistochemical analysis, and serum osteopontin levels were measured by an enzyme-linked immunosorbent assay.
RESULTS
There were no significant differences in mean (+/-SE) serum osteopontin levels between age-matched subjects with exposure to asbestos and subjects without exposure to asbestos (30+/-3 ng per milliliter and 20+/-4 ng per milliliter, respectively; P=0.06). In the group with exposure to asbestos, elevated serum osteopontin levels were associated with pulmonary plaques and fibrosis (56+/-13 ng per milliliter) but not with normal radiographic findings (21+/-5 ng per milliliter), plaques alone (23+/-3 ng per milliliter), or fibrosis alone (32+/-7 ng per milliliter) (P=0.004). Serum osteopontin levels were significantly higher in the group with pleural mesothelioma than in the group with exposure to asbestos (133+/-10 ng per milliliter vs. 30+/-3 ng per milliliter, P<0.001). Immunohistochemical analysis revealed osteopontin staining of the tumor cells in 36 of 38 samples of pleural mesothelioma. An analysis of serum osteopontin levels comparing the receiver-operating-characteristic curve in the group exposed to asbestos with that of the group with mesothelioma had a sensitivity of 77.6 percent and a specificity of 85.5 percent at a cutoff value of 48.3 ng of osteopontin per milliliter. Subgroup analysis comparing patients with stage I mesothelioma with subjects with exposure to asbestos revealed a sensitivity of 84.6 percent and a specificity of 88.4 percent at a cutoff value of 62.4 ng of osteopontin per milliliter.
CONCLUSIONS
Serum osteopontin levels can be used to distinguish persons with exposure to asbestos who do not have cancer from those with exposure to asbestos who have pleural mesothelioma.
Topics: Aged; Asbestos; Asbestosis; Biomarkers; Female; Humans; Male; Mesothelioma; Middle Aged; Neoplasm Staging; Occupational Exposure; Osteopontin; Pleural Neoplasms; ROC Curve; Regression Analysis; Sialoglycoproteins; Survival Analysis
PubMed: 16221779
DOI: 10.1056/NEJMoa051185