Peri-implant osseointegration after low-level laser therapy: micro-computed tomography and resonance frequency analysis in an animal model.

The purpose of the present study is to evaluate the effects of low-level laser therapy on the osseointegration process by comparing resonance frequency analysis measurements performed at implant placement and after 30 days and micro-computed tomography images in irradiated vs nonirradiated rabbits. Fourteen male New Zealand rabbits were randomly divided into two groups of seven animals each, one control group (nonirradiated animals) and one experimental group that received low-level laser therapy (Thera Lase®, aluminum-gallium-arsenide laser diode, 10 J per spot, two spots per session, seven sessions, 830 nm, 50 mW, CW, Ø 0.0028 cm2). The mandibular left incisor was surgically extracted in all animals, and one osseointegrated implant was placed immediately afterward (3.25ø × 11.5 mm; NanoTite, BIOMET 3i). Resonance frequency analysis was performed with the Osstell® device at implant placement and at 30 days (immediately before euthanasia). Micro-computed tomography analyses were then conducted using a high-resolution scanner (SkyScan 1172 X-ray Micro-CT) to evaluate the amount of newly formed bone around the implants. Irradiated animals showed significantly higher implant stability quotients at 30 days (64.286 ± 1.596; 95 % confidence interval (CI) 60.808-67.764) than controls (56.357 ± 1.596; 95 %CI 52.879-59.835) (P = .000). The percentage of newly formed bone around the implants was also significantly higher in irradiated animals (75.523 ± 8.510; 95 %CI 61.893-89.155) than in controls (55.012 ± 19.840; 95 %CI 41.380-68.643) (P = .027). Laser therapy, based on the irradiation protocol used in this study, was able to provide greater implant stability and increase the volume of peri-implant newly formed bone, indicating that laser irradiation effected an improvement in the osseointegration process.

Biomechanical evaluation of macro and micro designed screw-type implants: an insertion torque and removal torque study in rabbits.

OBJECTIVE: To investigate the combined effect of macro and pitch shortened threads on primary and secondary stability during healing, but before dynamic loading. MATERIALS AND METHODS: Two sets of turned implants with different macro geometry were prepared. The test group possessed pitch shortened threads in between the large threads and the control group did not have thread alterations. The two implant groups were placed in both femur and tibiae of 10 lop-eared rabbits, and at the time of implant insertion, insertion torques were recorded. After 4 weeks, all implants were subjected to removal torque tests. RESULTS: The insertion torque values for the control and test groups for the tibia were 15.7 and 20.6 Ncm, respectively, and for the femur, 11.8, and 12.8 Ncm respectively. The removal torque values for the control and test groups in the tibia were 7.9 and 9.1 Ncm, respectively, and for the femur, 7.9 and 7.7 Ncm respectively. There was no statistically significant difference between the control and test groups. CONCLUSION: Under limited dynamic load, the addition of pitch shortened threads did not significantly improve either the primary or the secondary stability of the implants in bone.

Readmission within three months after inpatient geriatric care-Incidence, diagnosis and associated factors in a Swedish cohort.

INTRODUCTION: Readmissions are very costly, in monetary terms but also for the individual patient's safety and health. Only by understanding the reasons and drivers of readmissions, it is possible to ensure quality of care and improve the situation. The aim of this study was to assess inpatient readmissions during the first three months after discharge from geriatric inpatient care regarding main diagnosis and frequency of readmission. Furthermore, the aim was to analyze association between readmission and patient characteristics including demography and socioeconomics, morbidity, physical function, risk screening and care process respectively. METHODS: The study includes all individuals admitted for inpatient care at three geriatric departments operated by the Stockholm region during 2016. Readmission after discharge was studied within three different time intervals; readmission within 10 days after discharge, within 11-30 days and within 31-90 days, respectively. Main diagnosis at readmission was assessed. RESULTS: One fourth of the individuals discharged from inpatient geriatric care was readmitted during the first three months after discharge. The most common main diagnoses for readmission were heart failure, chronic obstructive pulmonary disease and pneumonia. Statistically significant risk factors for readmission included age, sex, number of diagnoses at discharge, and to some extent polypharmacy and destination of discharge. CONCLUSIONS: Several clinical risk factors relating to physical performance and vulnerability were associated with risk of readmission. Socioeconomic information did not add to the predictability. To enable reductions in readmission rates, proactive monitoring of frail individuals afflicted with chronic conditions is necessary, and an integrated perspective including all stakeholders involved is crucial.

Clinical categories of patients and encounter rates in primary health care - a three-year study in defined populations.

BACKGROUND: The objective was to estimate the proportion of inhabitants with a diagnosis-registered encounter with a general practitioner, and to elucidate annual variations of clinical categories of patients in terms of their individual comorbidity. METHODS: A three-year retrospective study of encounter data from electronic patient records, with an annual-based application of the Johns Hopkins Adjusted Clinical Groups (ACG) system. Data were retrieved from every patient with a diagnosis-registered encounter with a GP during the period 2001-2003 at 13 publicly managed primary health care centres in Blekinge county, southeastern Sweden, with about 150000 inhabitants. MAIN OUTCOME MEASURES: Proportions of inhabitants with a diagnosis-registered encounter, and ranges of the annual proportions of categories of patients according to ACGs. RESULTS: The proportion of inhabitants with a diagnosis-registered encounter ranged from about 64.0% to 90.6% for the primary health care centres, and averaged about 76.5% for all inhabitants. In a three-year perspective the average range of categories of patients was about 0.4% on the county level, and about 0.9% on the primary health care centre level. About one third of the patients each year had a constellation of two or more types of morbidity. CONCLUSION: About three fourths of all inhabitants had one or more diagnosis-registered encounters with a general practitioner during the three-year period. The annual variation of categories of patients according to ACGs was small on both the county and the primary health care centre level. The ACG system seems useful for demonstrating and predicting various aspects of clinical categories of patients in Swedish primary health care.

The importance of comorbidity in analysing patient costs in Swedish primary care.

BACKGROUND: The objective was to explore the usefulness of the morbidity risk adjustment system Adjusted Clinical Groups (ACG), in comparison with age and gender, in explaining and estimating patient costs on an individual level in Swedish primary health care. Data were retrieved from two primary health care centres in southeastern Sweden. METHODS: A cross-sectional observational study. Data from electronic patient registers from the two centres were retrieved for 2001 and 2002, and patients were grouped into ACGs, expressing the individual combination of diagnoses and thus the comorbidity. Costs per patient were calculated for both years in both centres. Cost data from one centre were used to create ACG weights. These weights were then applied to patients at the other centre. Correlations between individual patient costs, age, gender and ACG weights were studied. Multiple linear regression analyses were performed in order to explain and estimate patient costs. RESULTS: The variation in individual patient costs was substantial within age groups as well as within ACG weight groups. About 37.7% of the individual patient costs could be explained by ACG weights, and age and gender added about 0.8%. The individual patient costs in 2001 estimated 22.0% of patient costs in 2002, whereas ACG weights estimated 14.3%. CONCLUSION: ACGs was an important factor in explaining and estimating individual patient costs in primary health care. Costs were explained to only a minor extent by age and gender. However, the usefulness of the ACG system appears to be sensitive to the accuracy of classification and coding of diagnoses by physicians.

Histologic and Resonance Frequency Analysis of Peri-Implant Bone Healing After Low-Level Laser Therapy: An In Vivo Study.

PURPOSE: To evaluate the effects of low-level laser therapy (LLLT) on peri-implant bone regeneration by means of resonance frequency analysis and histologic analysis of bone-to-implant contact (BIC). MATERIALS AND METHODS: Thirty-two male New Zealand rabbits were randomly divided into four groups of eight animals each, one control group (nonirradiated animals) and three experimental groups that received LLLT (group E5 = 5 J per session; group E10 = 10 J per session; group E20 = 20 J per session). The mandibular left incisor was surgically extracted in all animals, and a nanoparticle-treated-surface osseointegrated implant was placed immediately afterward. The experimental groups were irradiated with aluminum-gallium-arsenide laser diode every 48 hours over a 13-day period for a total of seven sessions. Implant stability quotients (ISQs) were measured at the time of implant placement and 30 days after the last LLLT session. The animals were then euthanized and dissected, and histologic slides of the implant region were obtained for BIC evaluation. RESULTS: Significant differences in ISQ were detected between groups before and after LLLT, with group E20 showing significantly higher values than controls. The percentage of BIC was also significantly higher in group E20 than in control animals. CONCLUSION: Laser therapy at a dose of 20 J per treatment session, based on the irradiation protocol used in this study, was able to significantly increase ISQ values and BIC after implant placement, indicating that laser irradiation effected an improvement in peri-implant bone healing.

Phosphorylation marks IPF1/PDX1 protein for degradation by glycogen synthase kinase 3-dependent mechanisms.

The transcription factor IPF1/PDX1 plays a crucial role in both pancreas development and maintenance of beta-cell function. Targeted disruption of this transcription factor in beta-cells leads to diabetes, whereas reduced expression levels affect insulin expression and secretion. Therefore, it is essential to determine molecular mechanisms underlying the regulation of this key transcription factor on mRNA levels and, most importantly, on protein levels. Here we show that a minor portion of IPF1/PDX1 is phosphorylated on serine 61 and/or serine 66 in pancreatic beta-cells. This phosphorylated form of IPF1/PDX1 preferentially accumulates following proteasome inhibition, an effect that is prevented by inhibition of glycogen synthase kinase 3 (GSK3) activity. Oxidative stress, which is associated with the diabetic state, (i) increases IPF1/PDX1 Ser61 and/or Ser66 phosphorylation and (ii) increases the degradation rate and decreases the half-life of IPF-1/PDX-1 protein. In addition, we provide evidence that GSK3 activity participates in oxidative stress-induced effects on beta-cells. Thus, this current study uncovers a new mechanism that might contribute to diminished levels of IPF1/PDX1 protein and beta-cell dysfunction during the progression of diabetes.

Skin diseases caused by ultraviolet radiation: the cost of illness.

OBJECTIVES: To assess the annual direct and indirect costs of skin diseases caused by ultraviolet radiation. METHODS: A model for cost-of-illness, including costs for hospital care, primary care, pharmaceuticals, mortality, and morbidity, for approximately 1.8 million inhabitants in Stockholm. RESULTS: The total annual discounted cost-of-illness in Stockholm was approximately 162 million SEK (MSEK; approximate 2002 exchange rate: 1 U.S. dollar = 10 SEK). The indirect costs were predominant and constituted approximately 91 MSEK (56% of total costs), mainly due to an estimated cost of mortality for cutaneous malignant melanoma of 84 MSEK. The direct costs of these diseases, approximately 71 MSEK, were predominated by hospital ambulatory care costs of approximately 33 MSEK. The direct costs constituted approximately 0.4% of the overall health-care costs for hospital care and primary health care in the area. CONCLUSIONS: Skin diseases caused by ultraviolet radiation result in moderate economic losses in the community. Therefore, it may not be easy to make successful prevention of these diseases economically beneficial.

Types of morbidity and categories of patients in a Swedish county. Applying the Johns Hopkins Adjusted Clinical Groups System to encounter data in primary health care.

OBJECTIVE: To elucidate types of morbidity and categories of patients in a large population. DESIGN: A one-year retrospective study of encounter data from electronic patient record databases in primary health care, with application of the Johns Hopkins Adjusted Clinical Groups System. SETTING: Blekinge County Council, southeastern Sweden, with 149 552 inhabitants. SUBJECTS: All patients with a diagnosis-registered encounter with a GP in 2002 at 13 publicly managed PHC centres. MAIN OUTCOME MEASURES: Anonymous identification number, age, gender, type of morbidity (Aggregated Diagnostic Groups), and category of patient (Adjusted Clinical Groups). RESULTS: About 45% of the county's inhabitants had at least one diagnosis-registered encounter with a GP during the year. The most common types of morbidity were "time limited" (24.0% of all types), "likely to recur" (19.6%), and "signs/symptoms" (19.0%). About 33.3% of all patients had one and only one time-limited condition, about 16.8% had one and only one recurring condition, and about 12.1% of the patients had only a chronic condition. CONCLUSION: Types of morbidity in primary health care are dominated by nearly equal proportions of "time limited", "likely to recur", "chronic", and "signs/symptoms". The predominant categories of patients are those with only one type of morbidity, while about one-third of the patients had a constellation of two or more types of morbidity during a one-year period.

Imaging of membrane lipids in single cells by imprint-imaging time-of-flight secondary ion mass spectrometry.

A new method for identification and localization of organic molecules in biological samples is described. The method involves making an imprint of a biological sample on a silver (Ag) surface and subsequent analysis of the imprint by imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS). Using this method, detection of unfragmented, Ag cationized molecules at a spatial resolution of <0.5 microm is possible. We have used the method to study the spatial distribution of phosphatidylcholine and cholesterol in blood cells adhering to a glass surface. The TOF-SIMS images show that cholesterol is preferentially located in the plasma membrane, whereas the phosphocholine shows highest concentration in the nuclear membrane. Scanning electron microscopy and fluorescence microscopy images show that the amount of transferred material during the imprinting process can be controlled by varying the imprinting pressure and pretreatment of the cell substrate prior to imprinting.