Hospital-administered ECPR for out-of-hospital cardiac arrest: an observational cohort study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a treatment method for refractory out-of-hospital cardiac arrest (OHCA) requiring a complex chain of care.

METHODS

All cases of OHCA between 1 January 2016 and 31 December 2021 in the Helsinki University Hospital catchment area in which the ECPR protocol was activated were included in the study. The protocol involved patient transport from the emergency site with ongoing mechanical cardiopulmonary resuscitation (CPR) directly to the cardiac catheterisation laboratory where the implementation of extracorporeal membrane oxygenation (ECMO) was considered. Cases of hypothermic cardiac arrest were excluded. The main outcomes were the number of ECPR protocol activations, duration of prehospital and in-hospital time intervals, and whether the ECPR candidates were treated using ECMO or not.

RESULTS

The prehospital ECPR protocol was activated in 73 cases of normothermic OHCA. The mean patient age (SD) was 54 (±11) years and 67 (91.8%) of them were male. The arrest was witnessed in 67 (91.8%) and initial rhythm was shockable in 61 (83.6%) cases. The median ambulance response time (IQR) was 9 (7-11) min. All patients received mechanical CPR, epinephrine and/or amiodarone. Seventy (95.9%) patients were endotracheally intubated. The median (IQR) highest prehospital end-tidal CO2 was 5.5 (4.0-6.9) kPa.A total of 37 (50.7%) patients were treated with venoarterial ECMO within a median (IQR) of 84 (71-105) min after the arrest. Thirteen (35.1%) of them survived to discharge and 11 (29.7%) with a cerebral performance category (CPC) 1-2. In those ECPR candidates who did not receive ECMO, 8 (22.2%) received permanent return of spontaneuous circulation during transport or immediately after hospital arrival and 6 (16.7%) survived to discharge with a CPC 1-2.

CONCLUSIONS

Half of the ECPR protocol activations did not lead to ECMO treatment. However, every fourth ECPR candidate and every third patient who received ECMO-facilitated resuscitation at the hospital survived with a good neurological outcome.

Cold Weather and Cardiac Arrest in 4 Seasons: Helsinki, Finland, 1997‒2018

Objectives. To test the a priori hypothesis that out-of-hospital cardiac arrest (OHCA) is associated with cold weather during all seasons, not only during the winter. Methods. We applied a case‒crossover design to all cases of nontraumatic OHCA in Helsinki, Finland, over 22 years: 1997 to 2018. We statistically defined cold weather for each case and season, and applied conditional logistic regression with 2 complementary models a priori according to the season of death. Results. There was an association between cold weather and OHCA during all seasons, not only during the winter. Each additional cold day increased the odds of OHCA by 7% (95% confidence interval [CI] = 4%, 10%), with similar strength of association during the autumn (6%; 95% CI = 0%, 12%), winter (6%; 95% CI = 1%, 12%), spring (8%; 95% CI = 2%, 14%), and summer (7%; 95% CI = 0%, 15%). Conclusions. Cold weather, defined according to season, increased the odds of OHCA during all seasons in similar quantity. Public Health Implications. Early warning systems and cold weather plans focus implicitly on the winter season. This may lead to incomplete measures in reducing excess mortality related to cold weather. (Am J Public Health. 2022;112(1):107-115. https://doi.org/10.2105/AJPH.2021.306549).

The Automated External Defibrillator: Heterogeneity of Legislation, Mapping and Use across Europe. New Insights from the ENSURE Study

INTRODUCTION

The rapid use of an automated external defibrillator (AED) is crucial for increased survival after an out-of-hospital cardiac arrest (OHCA). Many factors could play a role in limiting the chance of an AED use. We aimed to verify the situation regarding AED legislation, the AED mapping system and first responders (FRs) equipped with an AED across European countries.

METHODS

We performed a survey across Europe entitled "European Study about AED Use by Lay Rescuers" (ENSURE), asking the national coordinators of the European Registry of Cardiac Arrest (EuReCa) program to complete it.

RESULTS

Nineteen European countries replied to the survey request for a population covering 128,297,955 inhabitants. The results revealed that every citizen can use an AED in 15 countries whereas a training certificate was required in three countries. In one country, only EMS personnel were allowed to use an AED. An AED mapping system and FRs equipped with an AED were available in only 11 countries. The AED use rate was 12-59% where AED mapping and FR systems were implemented, which was considerably higher than in other countries (0-7.9%), reflecting the difference in OHCA survival.

CONCLUSIONS

Our survey highlighted a heterogeneity in AED legislation, AED mapping systems and AED use in Europe, which was reflected in different AED use and survival.

Prehospital characteristics of COVID-19 patients in Helsinki - experience of the first wave of the pandemic

Background

There is a lack of knowledge how patients with COVID-19 disease differ from patients with similar signs or symptoms (but who will have a diagnosis other than COVID-19) in the prehospital setting. The aim of this study was to compare the characteristics of these two patient groups met by the emergency medical services.

Methods

All prehospital patients after the World Health Organisation (WHO) pandemic declaration 11.3.2020 until 30.6.2020 were recruited for the study. The patients were screened using modified WHO criteria for suspected COVID-19. Data from the electronic prehospital patient reporting system were linked with hospital laboratory results to check the laboratory confirmation for COVID-19. For comparison, we divided the patients into two groups: screening- and laboratory-positive patients with a hospital diagnosis of COVID-19 and screening-positive but laboratory-negative patients who eventually received a different diagnosis in hospital.

Results

A total of 4157 prehospital patients fulfilled the criteria for suspected COVID-19 infection during the study period. Five-hundred-thirty-six (12.9%) of the suspected cases received a laboratory confirmation for COVID-19. The proportion of positive cases in relation to suspected ones peaked during the first 2 weeks after the declaration of the pandemic. In the comparison of laboratory-positive and laboratory-negative cases, there were clinically insignificant differences between the groups in age, tympanic temperature, systolic blood pressure, heart rate, on-scene time, urgency category of the call and mode of transportation. Foreign-language-speakers were overrepresented amongst the positive cases over native language speakers (26,6% vs. 7,4%, p < 0,001). The number of cases in which no signs or symptoms of COVID-19 disease were reported, but patients turned out to have a positive test result was 125 (0,3% of the whole EMS patient population and 11,9% of all verified COVID-19 patients encountered by the EMS).

Conclusions

In a sample of suspected COVID-19 patients, the laboratory-positive and laboratory-negative patients were clinically indistinguishable from each other during the prehospital assessment. Foreign-language-speakers had a high likelihood of having Covid-19. The modified WHO criteria still form the basis of screening of suspected COVID-19 patients in the prehospital setting.

Definition of the data for comprehensiveness in scenario analysis of near-surface nuclear waste repositories

This article provides data on the near-surface repository for nuclear waste in the associated Research article “Comprehensiveness of scenarios in the safety assessment of nuclear waste repositories” [1].We illustrate i) the parameters of the COMSOL Multiphysics model for calculating the radiological impact of the repository, ii) the set of scenarios analyzed following a pluralistic approach, and iii) nodes, experts’ beliefs and prior probabilities for the scenario analysis based on Bayesian networks.

Out-of-hospital cardiac arrest across the World: First report from the International Liaison Committee on Resuscitation (ILCOR)

BACKGROUND

Since development of the Utstein style recommendations for the uniform reporting of cardiac arrest, increasing numbers of national and regional out-of-hospital cardiac arrest (OHCA) registries have been established worldwide. The International Liaison Committee on Resuscitation (ILCOR) created the Research and Registries Working Group and aimed to systematically report data collected from these registries.

METHODS

We conducted two surveys of voluntarily participating national and regional registries. The first survey aimed to identify which core elements of the current Utstein style for OHCA were collected by each registry. The second survey collected descriptive summary data from each registry. We chose the data collected for the second survey based on the availability of core elements identified by the first survey.

RESULTS

Seven national and four regional registries were included in the first survey and nine national and seven regional registries in the second survey. The estimated annual incidence of emergency medical services (EMS)-treated OHCA was 30.0-97.1 individuals per 100,000 population. The combined data showed the median age varied from 64 to 79 years and more than half were male in all 16 registries. The provision of bystander cardiopulmonary resuscitation (CPR) and bystander automated external defibrillator (AED) use was 19.1-79.0% in all registries and 2.0-37.4% among 11 registries, respectively. Survival to hospital discharge or 30-day survival after EMS-treated OHCA was 3.1-20.4% across all registries. Favorable neurological outcome at hospital discharge or 30 days after EMS-treated OHCA was 2.8-18.2%. Survival to hospital discharge or 30-day survival after bystander-witnessed shockable OHCA ranged from 11.7% to 47.4% and favorable neurological outcome from 9.9% to 33.3%.

CONCLUSION

This report from ILCOR describes data on systems of care and outcomes following OHCA from nine national and seven regional registries across the world. We found variation in reported survival outcomes and other core elements of the current Utstein style recommendations for OHCA across nations and regions.

Mechanisms of early glucose regulation disturbance after out-of-hospital cardiopulmonary resuscitation: An explorative prospective study

Background

Hyperglycemia is common and associated with increased mortality after out-of-hospital cardiac arrest (OHCA) and return of spontaneous circulation (ROSC). Mechanisms behind ultra-acute hyperglycemia are not well known. We performed an explorative study to describe the changes in glucose metabolism mediators during the prehospital postresuscitation phase.

Methods

We included patients who were successfully resuscitated from out-of-hospital cardiac arrest in two physician-staffed units. Insulin, glucagon, and glucagon-like peptide 1 (GLP-1) were measured in prehospital and hospital admission samples. Additionally, interleukin-6 (IL-6), cortisol, and HbA1c were measured at hospital admission.

Results

Thirty patients participated in the study. Of those, 28 cases (71% without diabetes) had sufficient data for analysis. The median time interval between prehospital samples and hospital admission samples was 96 minutes (IQR 85–119). At the time of ROSC, the patients were hyperglycemic (11.2 mmol/l, IQR 8.8–15.7), with insulin and glucagon concentrations varying considerably, although mostly corresponding to fasting levels (10.1 mU/l, IQR 4.2–25.2 and 141 ng/l, IQR 105–240, respectively). GLP-1 increased 2- to 8-fold with elevation of IL-6. The median glucose change from prehospital to hospital admission was -2.2 mmol/l (IQR -3.6 to -0.2). No significant correlations between the change in plasma glucose levels and the changes in insulin (r = 0.30, p = 0.13), glucagon (r = 0.29, p = 0.17), or GLP-1 levels (r = 0.32, p = 0.15) or with IL-6 (r = (-0.07), p = 0.75), cortisol (r = 0.13, p = 0.52) or HbA1c levels (r = 0.34, p = 0.08) were observed. However, in patients who did not receive exogenous epinephrine during resuscitation, changes in blood glucose correlated with changes in insulin (r = 0.59, p = 0.04) and glucagon (r = 0.65, p = 0.05) levels, demonstrating that lowering glucose values was associated with a simultaneous lowering of insulin and glucagon levels.

Conclusions

Hyperglycemia is common immediately after OHCA and cardiopulmonary resuscitation. No clear hormonal mechanisms were observed to be linked to changes in glucose levels during the postresuscitation phase in the whole cohort. However, in patients without exogenous epinephrine treatment, the correlations between glycemic and hormonal changes were more obvious. These results call for future studies examining the mechanisms of postresuscitation hyperglycemia and the metabolic effects of the global ischemic insult and medical treatment.

International variation in survival after out-of-hospital cardiac arrest: A validation study of the Utstein template

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) survival varies greatly between communities. The Utstein template was developed and promulgated to improve the comparability of OHCA outcome reports, but it has undergone limited empiric validation. We sought to assess how much of the variation in OHCA survival between emergency medical services (EMS) across the globe is explained by differences in the Utstein factors. We also assessed how accurately the Utstein factors predict OHCA survival.

METHODS

We performed a retrospective analysis of patient-level prospectively collected data from 12 OHCA registries from 12 countries for the period 1 Jan 2006 through 31 Dec 2011. We used generalized linear mixed models to examine the variation in survival between EMS agencies (n=232).

RESULTS

Twelve registries contributed 86,759 cases. Patient arrest characteristics, EMS treatment and patient outcomes varied across registries. Overall survival to hospital discharge was 10% (range, 6% to 22%). Overall survival with Cerebral Performance Category of 1 or 2 (available for 8/12 registries) was 8% (range, 2% to 20%). The area-under-the-curve for the Utstein model was 0.85 (Wald CI: 0.85-0.85). The Utstein factors explained 51% of the EMS agency variation in OHCA survival.

CONCLUSIONS

The Utstein factors explained 51% of the variation in survival to hospital discharge among multiple large geographically separate EMS agencies. This suggests that quality improvement and public health efforts should continue to target modifiable Utstein factors to improve OHCA survival. Further study is required to identify the reasons for the variation that is incompletely understood.

Witnessed out-of-hospital cardiac arrest- effects of emergency dispatch recognition

BACKGROUND

Survival from an out-of-hospital cardiac arrest (OHCA) depends on the sequence of interventions in "the chain of survival". If OHCA is recognized in the emergency medical communication centre (EMCC), the proper emergency medical service (EMS) should be dispatched and cardiopulmonary resuscitation (CPR) instructions should be given to a bystander. The study aimed to examine the impact of OHCA recognition in the EMCC on survival rates and the main elements of the chain of survival.

METHODS

Data from the Helsinki University Hospital's registry of OHCA patients between 1997 and 2013 were studied. Altogether, 2054 EMCC-handled and bystander-witnessed OHCA proven events of cardiac origin were analysed.

RESULTS

In 80.5% of the victims, two EMS units were correctly dispatched and the OHCA was classified as recognized. Achieved return of spontaneous circulation (ROSC) and survival to hospital discharge were 49% and 23%, respectively, if cardiac arrest was recognized by the EMCC and 40% and 16% when it was not (P = 0.003 and 0.002). Dispatchers gave CPR instructions in 60% of the recognized OHCA cases. Bystander-performed CPR increased over time and was given in 58% of the recognized OHCAs and also in 17% of the unrecognized events. EMS delays were shorter if OHCA was recognized as opposed to unrecognized (8 min with an IQR 6.5-10 min vs. 9 min with an IQR 6.5-11 min; P = 0.001).

CONCLUSIONS

Recognition of OHCA by the EMCC was significantly associated with an increased rate of bystander-performed CPR, reduced EMS response time, and increased OHCA patient ROSC and survival rates.

Apples to apples or apples to oranges? International variation in reporting of process and outcome of care for out-of-hospital cardiac arrest

OBJECTIVES

Survival after out-of-hospital cardiac arrest (OHCA) varies between communities, due in part to variation in the methods of measurement. The Utstein template was disseminated to standardize comparisons of risk factors, quality of care, and outcomes in patients with OHCA. We sought to assess whether OHCA registries are able to collate common data using the Utstein template. A subsequent study will assess whether the Utstein factors explain differences in survival between emergency medical services (EMS) systems.

STUDY DESIGN

Retrospective study.

SETTING

This retrospective analysis of prospective cohorts included adults treated for OHCA, regardless of the etiology of arrest. Data describing the baseline characteristics of patients, and the process and outcome of their care were grouped by EMS system, de-identified, and then collated. Included were core Utstein variables and timed event data from each participating registry. This study was classified as exempt from human subjects' research by a research ethics committee.

MEASUREMENTS AND MAIN RESULTS

Thirteen registries with 265 first-responding EMS agencies in 13 countries contributed data describing 125,840 cases of OHCA. Variation in inclusion criteria, definition, coding, and process of care variables were observed. Contributing registries collected 61.9% of recommended core variables and 42.9% of timed event variables. Among core variables, the proportion of missingness was mean 1.9±2.2%. The proportion of unknown was mean 4.8±6.4%. Among time variables, missingness was mean 9.0±6.3%.

CONCLUSIONS

International differences in measurement of care after OHCA persist. Greater consistency would facilitate improved resuscitation care and comparison within and between communities.

Linkage of nicotine dependence and smoking behavior on 10q, 7q and 11p in twins with homogeneous genetic background

The significant worldwide health burden introduced by tobacco smoking highlights the importance of studying the genetic determinants of smoking behavior and the key factor sustaining compulsive smoking, that is, nicotine dependence (ND). We have here addressed the genetic background of smoking in a special study sample of twins, harmonized for early life events and specifically ascertained for smoking from the nationwide twin cohort of the genetically unique population of Finland. The twins and their families were carefully examined for extensive phenotype profiles and a genome-wide scan was performed to identify loci behind the smoking status, ND and the comorbid phenotype of ND and alcohol use in 505 individuals from 153 families. We replicated previous linkage findings on 10q (max logarithm of the odds (LOD) 3.12) for a smoker phenotype, and on 7q and 11p (max LOD 2.50, and 2.25, respectively) for the ND phenotype. The loci linked for ND also showed evidence for linkage for the comorbid phenotype. Our study provides confirmatory evidence for the involvement of these genome regions in the genetic etiology of smoking behavior and ND and for the first time associates drinking and smoking to a shared locus on 10q.

The 3DX multi image micro-CT device in clinical dental practice

OBJECTIVES

To evaluate the usefulness of 3DX multi-image micro-CT device in clinical dental practice.

METHODS

Images of 198 examinations performed with a 3DX device during a 6 month period in a private dental practice were evaluated retrospectively for the benefit of additional information compared with panoramic or intraoral radiographs.

RESULTS

The main indication for the use of 3DX micro-CT was planning of dental implant placement in 49% of the examinations. Diagnosis or exclusion of dental infection or peri-implantitis represented 28% of the examinations and tooth, root or foreign body localization represented 13%. Temporomandibular joint (TMJ) imaging and cyst or tumour diagnosis represented 7.5% and 2.5% of the examinations, respectively. In implant planning and tooth, root or foreign body localization examinations, the required information was obtained in every case except three implant planning examinations, in which the exact measurements were hampered by artefacts caused by root fillings and retrograde fillings or metal posts. When compared with conventional radiography, additional radiographic information was obtained in 51% of the micro-CT examinations performed to confirm or exclude dental infection or peri-implantitis. Micro-CT also showed the bone structure of TMJs precisely.

CONCLUSIONS

The 3DX micro-CT device visualizes bony anatomical structures precisely, which makes it a reliable tool for, for example, planning of implant treatment. The device is highly suitable for diagnosing dental infections. Dental restorations may cause disturbing artefacts and in 4.5% of the examinations the small imaging area resulted in re-examination.

A histological and immunohistochemical study of tissue reactions to solid poly(ortho ester) in rabbits

In many cases only the temporary presence of a biomaterial is needed in tissue support, augmentation or replacement. In such cases biodegradable materials are better alternatives than biostable ones. At present, biodegradable polymers are widely used in the field of maxillofacial surgery as sutures, fracture fixation devices and as absorbable membranes. The most often used polymers are aliphatic polyesters, such as polyglycolic acid (PGA) and polylactic acid (PLA). Poly(ortho ester) is a surface eroding polymer, which has been under development since 1970, but is used mostly in drug delivery systems in semisolid form. The aim of this study was to evaluate the tissue reactions of solid poly(ortho ester) (POE), histologically and immunohistochemically. Resorption times and the effect of 2 different sterilization methods (gamma radiation and ethylene oxide) upon resorption were also evaluated. Material was implanted into the tibia and subcutaneously into the mandibular ramus area of 24 rabbits. Follow-up times were 1-10, 14 and 24 weeks. Histological studies showed that POE induces a moderate inflammation in soft tissue and in bone. At 24 week follow-up, inflammation was mild in soft tissue and moderate in bone. In immunohistochemical studies, no highly fluorescent layer of tenascin or fibronectin was found adjacent to the implant. Resorption of gamma-sterilized rods was faster than ethylene oxide-sterilized rods. The total resorption time was more than 24 weeks in both groups. Clinically the healing was uneventful and the implants the well tolerated by the living tissue. This encourages these authors to continue studies with this interesting new material to search for the ideal material for bone filling and fracture fixation.

Biodegradable polydioxanone and poly(l/d)lactide implants: an experimental study on peri-implant tissue response

Several implants for orbital wall fracture treatment are available at the present, but they have drawbacks: resorption, risk for migration and foreign body reaction. Alloplastic resorbable implants would be advantageous: no removal operation and no donor side morbidity. The purpose of this study was to evaluate the foreign body reaction, capsule formation and mechanical properties of two bioresorbable implants. PDS and SR-P(L/DL)LA mesh sheet (70/30) with solid frame (96/4) implants (SR-P(L/DL)LA 70,96) were placed into subcutaneous tissue of 24 rats. Immunohistochemistry was used to evaluate reactivity for Tn-C, alpha-actin, type I and III collagens and two mononuclear cells: T-cells and monocyte/ macrophage. GPC, DSC and SEM were performed. Student's t-test or nonparametric Kruskall-Wallis test were used for statistical analysis. Histology of peri-implant capsule exhibited an inner cell-rich zone and an outer connective tissue zone around both materials. Tn-C reactivity was high in the inner and alpha-actin in the outer zone. At the end of the study, the difference of type I collagen versus type III collagen reactivity in inner zone was statistically significant (P<0.0001) as was the difference of type I collagen versus type III collagen reactivity in outer zone (P<0.0001). Immunohistochemistry did not reveal any statistical differences of T-cell and monocyte/macrophage reactivity around PDS versus SR-P(L/DL)LA 70,96 implants, nor any differences as a function of time. PDS were deformed totally after 2 months. SR-P(L/DL)LA 70,96 implants were only slightly deformed during the follow up of 7 months. PDS degraded rapidly in SEM observation. Particles were detaching from surface. SEM observation revealed that polylactide implant was degrading from the surface and the inner porous core became visible. The degradation came visible at 7 months. There were cracks in perpendicular direction towards to the long axis of the filaments. M(w) of PDS decreased fast compared to the polylactide implant. Foreign body reaction was minimal to both materials but continued throughout the whole observation period. Mechanically PDS was poor, it looses its shape totally within 2 months. It cannot be recommended for orbital wall reconstruction. New mesh sheet-frame structure (SR-P(L/DL)LA 70,96) approved to be mechanically adequate for orbital wall reconstruction. It seems not to possess intrinsic memory and retains its shape. The resorption time is significantly longer compared to PDS and is comparable to other studied P(L/DL)LA copolymers. Thus, the new polylactide copolymer implant may support the orbital contents long enough to give way to bone growth over the wall defect.

Radioactive contamination in the Arctic--sources, dose assessment and potential risks

Arctic residents, whose diets comprise a large proportion of traditional terrestrial and freshwater foodstuffs, have received the highest radiation exposures to artificial radionuclides in the Arctic. Doses to members of both the average population and selected indigenous population groups in the Arctic depend on the rates of consumption of locally-derived terrestrial and freshwater foodstuffs, including reindeer/caribou meat, freshwater fish, goat cheese, berries, mushrooms and lamb. The vulnerability of arctic populations, especially indigenous peoples, to radiocaesium deposition is much greater than for temperate populations due to the importance of terrestrial, semi-natural exposure pathways where there is high radiocaesium transfer and a long ecological half-life for this radionuclide. In contrast, arctic residents with diets largely comprising marine foodstuffs have received comparatively low radiation exposures because of the lower levels of contamination of marine organisms. Using arctic-specific information, the predicted collective dose is five times higher than that estimated by UNSCEAR for temperate areas. The greatest threats to human health and the environment posed by human and industrial activities in the Arctic are associated with the potential for accidents in the civilian and military nuclear sectors. Of most concern are the consequences of potential accidents in nuclear power plant reactors, during the handling and storage of nuclear weapons, in the decommissioning of nuclear submarines and in the disposal of spent nuclear fuel from vessels. It is important to foster a close association between risk assessment and practical programmes for the purposes of improving monitoring, formulating response strategies and implementing action plans.

Does apolipoprotein E influence learning and memory in the nondemented oldest old?

The objective of this study was to analyze the relationship of the apolipoprotein E (apoE) epsilon4 and epsilon2 alleles to learning and memory performances in the nondemented oldest old. Forty-six nondemented persons aged 85 years or over from a randomly selected group of 128 subjects in Vantaa, Finland, were studied. ApoE genotyping was performed using the minisequencing technique. A structured clinical examination and interview were carried out. The test variables studied were learning and memory scores (from the Fuld Object-Memory Evaluation), verbal fluency, and conceptualization (the Similarities subtest of the WAIS-R). We compared apoE-epsilon4 carriers to noncarriers and apoE-epsilon2 carriers to noncarriers. No statistically significant differences were found in any of the test variables. The results failed to confirm the hypotheses that poor cognitive performance is associated with the apoE-epsilon4 allele and good performance with the apoE-epsilon2 allele in the oldest old. This suggests that the apoE alleles do not have a detectable relationship to learning and memory in nondemented very elderly people.

The effect of age and density of the breast on the sensitivity of breast cancer diagnostic by mammography and ultasonography

PURPOSE

We studied which, age of the patient or density of the breast accounts for the sensitivity of mammography and ultrasonography (US). Furthermore we studied whether the overall impression on the density of the breast or the density in tumour area accounts for the sensitivity of mammography and ultrasonography.

MATERIALS AND METHODS

The material consisted of 572 consecutive histologically and 5 cytologically verified breast cancer cases. Mammography and US examinations were performed immediately before breast cancer operations and information on the findings were received from the original patient files and classified as malignant or benign. The density of breast parenchyma to fatty, mixed or dense in total breast and separately in tumour area was defined by a radiologist group from the original mammograms by comparing to model mammograms. The sensitivity (Se) of mammography and US was compared in 3 age groups (26-49, 50-59 and 60-92) and in the different density classes.

RESULTS

Sensitivity of mammography increased by age (density-adjusted OR = 0.2, 95%, CI 0.1-0.5) in age group 26-49 compared to age group 60-92) and with fattiness of the breast (age-adjusted OR= 0.4, 95%, CI 0.1-1.0 for dense breast parenchyma in tumour area compared to fatty breast). Sensitivity of US was inversely related to age (density-adjusted OR = 2.3, 95%, CI 1.0-5.2 in age group 26-49 compared to age group 60-92) and directly related with fattiness of breast (age-adjusted OR = 0.5, 95%, CI 0.2-0.9 by dense breast parenchyma in tumour area compared to fatty breast). Density in the tumour area compared to total breast density was related only mariginally better sensitivity both of mammography (0.4 vs. 0.6) and of US (0.5 vs. 0.6).

CONCLUSION

Sensitivity of both mammography and sensitivity of US are independently related both to the age of the patient and to the density of the breast. The effect of age is inverse and that of density parallel between mammography and US on sensitivity. The effect of overall breast density was close to the effect of density at the site of the tumour on the sensitivity of both mammography and US.

A comparative study on four screw-plate locking systems in sheep: a clinical and radiological study

Four mandibular screw-plate locking systems were studied in sheep. Three to four centimetres angular continuity resections of the mandible were performed and the defects bridged with pre-bent angular reconstruction plates fixed with four screws in the body part and three in the ramus. Each type was used four times. Clinical and radiological examinations were carried out 1 and 2 months later. All sheep were able to eat and ruminate normally throughout the postoperative period. Radiology revealed that 6/16 plates and 5/112 screws fractured during the follow-up period. In one type, no fracture occurred. Screw fracture was confined to just one reconstruction system. Six of 16 mandibles showed slight to moderate bone resorption under the plate. The results point to the internal shortcomings of the systems tested.

Validity of radiological examinations of patients with breast cancer in different age groups in a population based study

By studying which radiological examinations had been performed before breast cancer operations the aim was to assess, how much benefit ultrasonography (US) and fine or core needle biopsy (FNAB, CNB) gave in addition to mammography, and whether the sensitivity of these examinations varied with the age of the patient. There were 659 consecutive histologically and six cytologically verified breast cancer cases included in the study. Information on mammography, US and FNAB findings were retrieved from the original patient files and classified as malignant or benign. The sensitivity (Se) of these was compared in three age groups (26-49, 50-59 and 60-92). Seventeen (3%) tumours had operations without any radiological examination and 73 (11%) without cytological or histological verification. The sensitivity of mammography (Se=0.92) was statistically significantly higher than the sensitivity of FNAB (Se=0.85, P=0.002) or US (Se=0.86, P=0.003). The sensitivity of mammography increased with age; US sensitivity was slightly higher amongst younger than older patients; the sensitivity of FNAB did not depend on the age of the patient. The sensitivity using a cutoff level of class 5 for mammography was higher (50% typical malignant findings) than for US (45%) or FNAB (30%). Among cases with benign mammographic finding (classes 1-2), the US finding was malignant (classes 3-5) in 4% and FNAB was malignant in 7%. Mammography is a reliable method of breast examination especially for women over 50 years of age. Ultrasonography is beneficial, particularly in younger women, but it is mainly performed as a complementary examination to a mammography and therefore could not be evaluated as an independent examination. FNAB and CNB results were not related to the age of the patient.

The visibility of cancer on previous mammograms in retrospective review

AIM

To study how many tumours were visible in restrospect on mammograms originally reported as normal or benign in patients coming to surgery with proven breast cancer. The effect of making the pre--operative mammogram available was also assessed.

MATERIALS AND METHODS

Three hundred and twenty initial mammograms of consecutive new breast cancer cases were analysed by a group of radiologists in the knowledge that all patients were later diagnosed with breast cancer. The films were read twice, first without and then with the later (pre-operative) mammograms available. The parenchymal density in the location of the tumour was classified as fatty, mixed or dense, and the tumours were classified as visible or not visible. The reasons for the invisibility of the tumour in the earlier examination were analysed.

RESULTS

Fourteen per cent (45) of cancers were retrospectively visible in earlier mammograms without the pre-operative mammograms having been shown, and 29% (95) when pre-operative mammograms were shown. Breast parenchymal density decreased with age and the visibility of tumours increased with age. When considered simultaneously, the effect of age (over 55 vs under 55) was greater (OR = 2.9) than the effect of density (fatty vs others) (OR = 1.5). The most common reasons for non-detection were that the lesion was overlooked (55%), diagnosed as benign (33%) or was visible only in one projection (26%). Growing density was the most common (37%) feature of those lesions originally overlooked or regarded as benign.

CONCLUSIONS

Tumours are commonly visible in retrospect, but few of them exhibit specific signs of cancer, and are recognized only if they grow or otherwise change. It is not possible to differentiate most of them from normal parenchymal densities. Saarenmaa, I. (2001). Clinical Radiology56, 40-43.

International Arctic Seas Assessment Project

The International Atomic Energy Agency responded to the news that the former Soviet Union had dumped radioactive wastes in the shallow waters of the Arctic Seas, by launching the International Arctic Seas Assessment Project in 1993. The project had two objectives: to assess the risks to human health and to the environment associated with the radioactive wastes dumped in the Kara and Barents Seas; and to examine possible remedial actions related to the dumped wastes and to advise on whether they are necessary and justified. The current radiological situation in the Arctic waters was examined to assess whether there is any evidence for releases from the dumped waste. Potential future releases from the dumped wastes were predicted, concentrating on the high-level waste objects containing the major part of the radionuclide inventory of the wastes. Environmental transport of released radionuclides was modelled and the associated radiological impact on humans and the biota was assessed. The feasibility, costs and benefits of possible remedial measures applied to a selected high-level waste object were examined. Releases from identified dumped objects were found to be small and localised to the immediate vicinity of the dumping sites. Projected future annual doses to members of the public in typical local population groups were very small, less than 1 microSv--corresponding to a trivial risk. Projected future doses to a hypothetical group of military personnel patrolling the foreshore of the fjords in which wastes have been dumped were higher, up to 4 mSv/year, which still is of the same order as the average annual natural background dose. Moreover, since any of the proposed remedial actions were estimated to cost several million US$ to implement, remediation was not considered justified on the basis of potentially removing a collective dose of 10 man Sv. Doses calculated to marine fauna were insignificant, orders of magnitude below those at which detrimental effects on fauna populations might be expected to occur. Remediation was thus concluded not to be warranted on radiological grounds.

The visibility of cancer on earlier mammograms in a population-based screening programme

The aim of this study was to examine how frequently the later-round screen-detected and interval breast cancers were visible in earlier screening mammograms by retrospective review and to compare their radiological and clinicopathological features with those diagnosed by primary screening. In a population-based mammography screening programme 63,731 women aged 50-59 years were invited and 56,158 examinations were carried out in the period 1987-1992 in the Tampere area in Finland. A total of 276 breast cancers were detected, of which 131 were diagnosed on later screening rounds or were interval cancers. A retrospective review of previous screening mammograms was carried out in 130 cases by the radiologist who diagnosed the breast cancer and thus knew the exact location of the tumour, no blinded review was carried out. 43 (33%) cancers were visible, 84 (65%) were not visible and 3 (2%) not included on the mammogram in a retrospective review. Later round screen-detected cancers were statistically significantly more often visible in earlier screening mammograms (43%) than interval cancers (19%) (P = 0.002). Tumours missed by screening mammography but which were visible on retrospective review were often histologically well-differentiated and were more often diagnosed in the subsequent screening round than by clinical diagnosis as interval cancers. If all retrospectively visible interval cancers had been diagnosed by screening 19% (10/54) of the interval cancers could have been avoided. If all retrospectively visible cancers had been diagnosed at the time of false-negative screening or assessment 65% (84/130) of all patients would have benefitted from an earlier diagnosis compared with the actual figure of 31% (41/130).

Mixture of epsilon-caprolactone-lactide copolymer and tricalcium phosphate: a histological and immunohistochemical study of tissue reactions

In cranio-maxillofacial surgery, bone transplantation is needed for treatment of bony defects. An autograft, allograft or biomaterial can be used. Autogenous bone grafts are considered to be the best materials available, but there are some disadvantages in their use including donorsite morbidity, need for a second operative site and limited graft supply. A search for new bone-graft materials therefore remains necessary. We prepared a mixture of tricalcium phosphate (TCP), which is a resorbable, non-toxic, osteoconductive ceramic material and epsilon-caprolactone-lactide copolymer P(epsilon-CL/DL-LA), a resorbable polymer, and placed it in the dermis and in mandibular bone defects in 13 rabbits. Follow-up times were two, three, seven, eight, 12, 15 and 18 weeks, tissue reactions were assessed, histologically and immunohistochemically. Times of resorption of the material from tissues were reported. We found that the mixture caused a mild inflammatory reaction when placed in bone and severe inflammation when placed in dermis. No highly fluorescent layer of tenascin or fibronectin was found surrounding the implant area. The mixture was excellent to handle and very easy to place into bone defects. The results are promising and have led us to continue development of the mixture.

Lag-screw fixation of anterior mandibular fractures using biodegradable polylactide screws: a preliminary report

PURPOSE

The purpose of this study was to evaluate the utility of biodegradable, self-reinforced poly-L-lactide screws (SR-PLLA) for lag-screw fixation of anterior mandibular fractures.

PATIENTS AND METHODS

SR-PLLA lag-screws were used to stabilize anterior mandibular fractures in 11 patients. Maxillomandibular fixation was used to treat concomitant mandibular condyle fractures for 2 weeks in four patients and for 1 and 5 weeks in two patients. Clinical and radiologic follow-up lasted for 6 months in 36% of patients and for 1 year in 64%.

RESULTS

Healing of all anterior fractures was uneventful, with no displacement or delay of bony union. No adverse reactions to the biodegradable screws were seen during follow-up.

CONCLUSION

Biodegradable SR-PLLA screw fixation seems to be a new and promising way of treating anterior mandibular fractures.

Neuromuscular functioning of athletes and non-athletes in the drop jump

In many sports vertical jumping is important. This study compared neuromuscular functioning of the lower extremity muscles together with some kinetic and kinematic parameters before and during ground contact in drop jumps from two heights [0.4 m (DJ40) and 0.8 m (DJ80)] in 7 highly trained triple-jumpers and 11 physically active controls. The triple-jumpers jumped 32% higher in DJ40 and 34% higher in DJ80, had shorter braking and total contact times, and greater average and peak vertical ground reaction forces than the controls. In both drop jumps in the electromyogram pre-activity of the vastus lateralis and gastrocnemius muscles started earlier in the jumpers than in the controls. For the control group the increase in dropping height was associated with a decrease in the propulsion force, and resulted in more extended knee and ankle angles at touch down and more flexed angles at the deepest position than for the jumpers. All angular displacements for DJ80 were larger than for DJ40 in the control group. The triple jumpers and control subjects differed with respect to their neuromuscular functioning in the drop jump exercise and they responded in a different way to the increase in dropping height.

Fibrous wound repair associated with biodegradable poly-L/D-lactide copolymer implants: study of the expression of tenascin and cellular fibronectin

Extracellular matrix (ECM) proteins are known to play a role in inflammatory and hyperplastic processes. Our aim in the present study was to study the distribution of tenascin (Tn), cellular fibronectins (cFn) and myofibroblasts around biodegradable poly-L/D-lactide (PLA) implants with monoclonal antibodies (MAb). Ethylene-oxide and gamma-irradiation sterilized PLA plate-type implants were inserted into the dorsal subcutaneous tissue of ten adult rabbits. Follow-up times were 4, 12, 16, 36 and 48 wk. Only some inflammatory cells were observed. In electron microscopy, a close coherence between the implant and the stromal tissue was seen. Immunoreactivity for Tn, cFn and alpha-actin was detected as a distinct layer bordering the implant, regardless of the sterilization method for the first 36 wk. From week 36 onwards, Tn immunoreactivity was downregulated while cFn immunoreactivity still persisted. A moderate upregulation for myofibroblasts was seen on the week 48 specimens, when hydrolysation of PLA implant had started. The persistent content of myofibroblasts, Tn and cFn suggests a prolonged wound healing produced by PLA implants. The absence of Tn at the week 48 specimens suggests that cFn, rather than Tn may be needed for alpha-actin-mediated contraction by myofibroblasts.

The 3-dimensional kinematics of the walking gait cycle of children aged between 10 and 24 months: cross sectional and repeated measures

The purpose of this study was to examine the 3-dimensional kinematics of 'normal' walking gait in young children. A cross sectional study using nine children aged between 10 and 24 months, filmed whilst walking at natural speed, was undertaken using two gen-locked video cameras. The children were at different stages of walking development (from 0.5 to 10 months of independent walking (IW)). Repeated measures were taken from two of the children at 10 and 17 months of age and then at 18 and 24 months respectively. 3-dimensional video digitisation techniques utilising the DLT algorithm were used to obtain variables of the gait cycle. The position and movement of the arms were identified as potential motor development patterns. Ranges of movement and motion patterns observed in other variables are useful to determine 'normal' walking gait in such young children. The knees and hips were flexed throughout the gait cycle. Inter-limb asymmetries were observed for the knee angle pattern and for the stance and swing phase time. The mean stance phase time and double support time were 4 and 15% (respectively) greater than in adult's gait. The findings of this study are useful as a guide to research, teaching and clinical professions in this area of biomechanics. Copyright 1998 Elsevier Science B.V.

Biocompatibility of solid poly (ortho ester)

In previous studies poly (ortho ester) (POE) has shown promise as a resorbable device, a hemostatic sealant and as a carrier for drugs in bone surgery. The aim of this study was to evaluate the tissue reactions of solid poly (ortho ester) implanted into both tibiae of 17 rabbits. One half of the rods were sterilized by gamma radiation and the other half by ethylene oxide. The follow-up times were from 1 week to 21 weeks, after which the animals were killed and the bony specimens examined histologically. The connective tissue samples were examined immunohistochemically in order to study the occurrences of two extracellular matrix glycoproteins, tenascin and fibronectin. The results showed that solid poly (ortho ester)s induce a moderate inflammatory reaction for 9 weeks. Tenascin and fibronectin were present in samples from 1 week up to 4 weeks. It was also found that gamma sterilized POE was resorbed at week 7 and ethylene oxide sterilized POE at week 13.

Reliability of variables in the kinematic analysis of spring hurdles

The purpose of this study was to investigate the reliability of kinematic variables in spring hurdles and to find out how many trials are needed to achieve reliable data. Seven British National level athletes in sprint hurdles were videotaped and all eight trials of each athlete were digitized from two camera views to produce three dimensional coordinates. The reliability of 28 kinematic variables across eight trials ranged from 0.54 to 1.00 for females and from 0.00 to 0.99 for males. The number of trials needed to reach a certain reliability level was evaluated using Spearman-Brown prophecy formula, and in the worst case (horizontal velocity lost for males) 78 trials would be needed to reach 0.90 reliability. The results showed reasonably high reliability, and the values for the female trials were generally higher than the male trials. The relative height of the hurdles enforces a more demanding clearance for males that can lead to increased variation within the subjects and thus lowered reliability. Subsequently, the results indicate that often more than one trial is needed to provide accurate quantitative results of the technique.

3-D biomechanical analysis of sprint hurdles at different competitive levels

Four different competition sessions were examined using three-dimensional video techniques to study the hurdle clearance at different levels of performance in male and female athletes. In total, 28 trials were digitized (50 Hz) using the "Kine Analysis" software package. The Direct Linear Transformation algorithm and cross-validated quintic spline were carried out for the data. This study showed that the better female group performed with a greater take-off distance (P = 0.0006), making a lower take-off angle possible. This results in a greater horizontal velocity (P = 0.0002) than the lower level female group. Relative to the horizontal displacement of the CM from take-off to landing, the CM parabola peak occurred at 54 +/- 4% and 55 +/- 6% from take-off for the two male groups and 54 +/- 7% and 51 +/- 3% for the two female groups. There were no statistically significant differences between either the male groups or the female groups or the sexes. This would indicate that the relative peaks are at a similar point in the different parabolic paths. However, in absolute terms the peak occurred at different positions in the different groups. The reason for this is unclear and will need further investigation.

The bcl-2 gene status of human head and neck cancer cell lines

The bcl-2 oncogene was originally found in the translocation in a pre-B cell acute lymphocytic leukemia cell line. Since then a high expression of Bcl-2 has been found in many types of cancer. The bcl-2 gene encodes an intracellular membrane-associated protein. Overexpression of bcl-2 inhibits apoptosis induced by many drugs and radiation. In this study the bcl-2 gene status of 9 human head and neck squamous cell carcinoma cell lines was studied. Mutations of the bcl-2 gene were studied at mRNA and DNA levels. The presence and abundance of the Bcl-2 protein in cells were also investigated. In earlier studies the p53 tumour suppressor gene was screened for point mutations, and the radiosensitivity of these cell lines was measured. We were able to amplify bcl-2 cDNA from 5 of the 9 cell lines, which shows that bcl-2 was expressed in these cells. No point mutations were found in the bcl-2 gene in any of these cell lines. Loss of heterozygosity was observed in 2 cell lines at the bcl-2 locus, and these cell lines had no detectable levels of bcl-2 mRNA or Bcl-2 protein. The Bcl-2 protein was abundant in the cell lines with the wild-type p53 gene, and these cell lines were radioresistant. The Bcl-2 protein was also found in many other cell lines in mitotic cells. It seems that cells expressing bcl-2 are radioresistant, and even functional p53 cannot induce apoptosis in these cells.

Adiabatic transformability hypothesis of human locomotion

It is hypothesized that metabolic and mechanical changes in human locomotion associated with changes in speed v are constrained by two attractive strategies: Qmetab = 1 and delta Qmetab/delta v = a positive definite constant. Qmetab = delta Eks-1/ml O2s-1 where delta Eks-1 is the summed increments and decrements per unit time in the translational and rotational kinetic energies of the body's segments and ml O2s-1 is the rate at which chemical energy is dissipated. The expected constancy of delta Qmetab/delta v was derived from an extension of Ehrenfest's adiabatic hypothesis by which transformations (increases, decreases) in locomotion v can be considered as adiabatic, even though the biological conditions are nonconservative and non-rate-limited. The expected significance of Qmetab = 1 was derived from stability considerations of the symmetry per stride of stored and dissipated energy. An experimental evaluation was provided by collecting metabolic and mechanical measures on walking (10 subjects) and running (9 subjects) at progressively greater treadmill speeds but within the aerobic limit. Results revealed that walking was restricted to Qmetab < or = 1, with a nonlinear trajectory in v x Qmetab coordinates shaped by Qmetab = 1 (primarily) and the constancy of delta Qmetab/delta v. Running satisfied Qmetab > 1, with a linear trajectory in v x Qmetab coordinates conforming to delta Qmetab/delta v = a constant, with the constant predicted from invariants in the mechanical space v x delta Eks-1. Results also suggested that the metabolic costs of running might be predictable from measures made in the v x delta Eks-1 space.

Solid-phase minisequencing confirmed by FISH analysis in determination of gene copy number

The solid-phase minisequencing method (Syvnen et al. 1990) allows accurate quantative determination of the ratio between two DNA or RNA sequences that are present as a mixture in a sample and differ from each other only by a single nucleotide. Here, we present another application of the minisequencing method, the determination of the gene copy number in a genome. The copy number of a marker gene aspartyl glucosaminidase (AGA) located at 4qter, was determined in three patients with a chromosomal alteration involving the distal region of 4q. For the minisequencing assay an equal amount of DNA from a patient homozygous for a mutation in the AGA gene was added to the DNA samples concerned. The relative amount of the normal sequence determined in each combined sample gives the copy number of the AGA gene. Fluorescence in situ hybridization (FISH), applied in parallel as a control, produced concordant results with solid-phase minisequencing in each case. As the potential of the minisequencing lies in automation, it could be a useful tool in the screening of monosomies, trisomies or loss of heterozygosity in diagnostics.

Idiopathic macrocytic anaemia in the aged: molecular and cytogenetic findings

Macrocytosis in the elderly is often caused by abnormalities of haematological stem cell differentiation. In this study, a group of elderly patients was analysed for four molecular and cell biological parameters. The aim of the study was to screen elderly patients with idiopathic macrocytic anaemia or MDS for a set of alterations which are related to haematological dysplasia. The analyses used were: DNA-methylation at the calcitonin A gene 5'-area, NRAS point mutations at codons 12 and 13, in vitro colony formation of peripheral blood progenitor cells and cytogenetics of bone marrow cells. The results show that a significant portion of elderly patients with idiopathic macrocytosis have one or more of the abnormalities analysed. Hypermethylation of the calcitonin A gene 5'-area at the chromosome 11 band p15 is relatively common (7/15). Chromosomal aberrations (3/12) and NRAS oncogene point mutations (0/15) were rare findings. In vitro culture of erythroid progenitor cells was relatively frequently abnormal (7/15). Eight of our nine macrocytic patients who did not fulfill the FAB criteria for MDS had at least one of the alterations studied; this suggests that these patients might represent early phases of a stem cell disorder.

Calcitonin gene-related peptide (CGRP) and its effects on protein release in vitro in the developing submandibular gland of the rat

Indirect immunohistochemical methods were used to study presence and number of CGRP-immunoreactive (CGRP-IR) nerve fibers in the submandibular gland and ganglion cells of the superior cervical, submandibular and trigeminal ganglia of the developing rat. The effect of CGRP on peroxidase and total protein release was also studied in the developing postnatal submandibular glands of 1, 5, 12 and 30-day-old, as well as adult rats by in vitro methods. The possible costimulation of CGRP with SP, NKA or carbachol on 5-day-old and adult rats was also tested. The stimulatory effects of these compounds were compared to the basic release of peroxidase and total amount of proteins from submandibular gland fragments in incubation solution. CGRP-IR nerve fibers were found in relatively high number during post-natal development, mainly around blood vessels and ducts. Some CGRP-IR nerve fibers were also detected around acini. The number of these fibers was quite low and remained constant during the post-natal development. The number of CGRP-IR trigeminal ganglion cells was higher on the 5th and 12th post-natal day than later in development and in adult animals. At the same time, superior cervical- and submandibular ganglion cells were non-reactive for CGRP, suggesting trigeminal origin of CGRP-IR nerve fibers during the development in the submandibular gland. In the secretory studies, CGRP per se stimulated both peroxidase and total protein release in the submandibular gland most effectively on 5th and 12th post-natal days, while there was no clear secretory response in the adult glands. In the 5-day-old submandibular gland CGRP in combination with SP, NKA or carbachol clearly enhanced the total protein secretory response when compared with the release caused by these substances alone. However, in the adult submandibular gland, the combinations did not enhance total protein release more than any of the substances alone. Furthermore, it can be concluded that the presence of a more dense CGRP-IR innervation during the early postnatal period in the developing submandibular gland is accompanied with an increased responsiveness of the secretory elements to CGRP.

Characterization of binding sites and effects of calcitonin gene-related peptide (CGRP) and CGRP 8-37 on regional blood flow in rabbit salivary glands

Calcitonin gene-related peptide (CGRP) is a neuropeptide present in nerve fibres of salivary glands in several species, including man. One of the major targets of these nerve fibres are blood vessels of the glands. The presence and distribution of specific binding sites for CGRP in the rabbit major salivary glands was here investigated autoradiographically. In order to determine the physiological role of CGRP, regional blood flow was measured after intravenous (i.v.) or intra-arterial (i.a.) administration of CGRP or the antagonist CGRP 8-37, using a microsphere technique. Specific binding sites for CGRP were found in the parotid, submandibular and sublingual glands, distributed mainly in the muscular and endothelial layers of the blood vessel walls. CGRP injected i.a. (10 pmol/kg) caused a significant increase in regional blood flow in all major salivary glands. However, i.v. infusion of CGRP (120 pmol/kg) decreased regional blood flow in the parotid and sublingual glands, due to a general decrease in peripheral resistance and redistribution of peripheral blood flow. CGRP 8-37 given i.a. together with CGRP significantly inhibited the blood-flow increase by CGRP alone. It is concluded that most of the CGRP receptors in the rabbit salivary glands are localized in vascular elements. The physiological data show that CGRP acts as a vasodilator in the major salivary glands of the rabbit in vivo, and that the effect of CGRP is inhibited by the CGRP antagonist CGRP 8-37.

FRAXA locus in fragile X diagnosis: family studies, prenatal diagnosis, and diagnosis of sporadic cases of mental retardation

Three hundred eighty-seven individuals from 32 Finnish fragile X families were studied, using the probe StB12.3 [Oberlé et al., 1991: Science 252:1097-1102] for the FRAXA locus, to reveal length variations in the FMR-1 gene. As expected, the affected individuals (with few exceptions) showed a full mutation; a few affected individuals with a premutation only were found. Seventy percent of the females with a full mutation were affected. The size of the mutation remained unchanged in 6, increased in 73, and decreased in 6 female meioses. In male meioses the size was unchanged in 15 cases, increased in 2 cases, and decreased in 1 case. Prenatal diagnosis was performed in 20 cases. In 7 of these the mutation was inherited by the fetus. Four hundred sixty-four mentally retarded patients were referred to us for FRAXA analysis. In 5% of these the fragile X mutation was found. In addition to the clear cut negative or positive results there were 6 cases in which an increase of 50-80 bp was detected. These findings may represent either large normal alleles or small premutations suggesting a possible tissue mosaicism which could explain the retardation of the patients.

The sympathetic and parasympathetic nature of neuropeptide Y-immunoreactive nerve fibres in the major salivary glands of the rat

The distribution and origin of neuropeptide Y in the major salivary glands of the rat was studied by indirect immunofluorescence technique. Numerous nerve fibres immunoreactive for the peptide were seen in the parotid and sublingual glands. Most of the fibres were located around blood vessels and salivary acini. In the submandibular gland the number of immunoreactive nerve fibres around the acini was lower in comparison with that in the parotid and sublingual glands. Some immunoreactive nerve fibres were also found around or along intra- and interlobular ducts in all major salivary glands. A large number of the neuropeptide-containing neuronal cell bodies and nerve fibres were detected in the sympathetic superior cervical ganglion. Sympathetic postganglionic nerve trunks of this ganglion contained numerous immunoreactive nerve fibres as well. A subpopulation of the neuronal cell bodies in the submandibular ganglion were immunoreactive to neuropeptide Y. Both uni- and bilateral superior cervical ganglionectomies caused a significant decrease in the number of immunoreactive nerve fibres around the blood vessels in all the major salivary glands. However, these denervations did not affect the density of nerve fibres around the acini and ducts. On the contrary, unilateral parasympathetic denervation by sectioning the auriculotemporal nerve reduced the fibres around the secretory acini in the parotid gland remarkably, while only a minor reduction in the density of immunoreactive fibres associated with the blood vessels of the gland was detected. Unilateral electrocoagulation of the trigeminal nerve branches caused no detectable change in the density of immunoreactive nerve fibres in any of the major salivary glands.(ABSTRACT TRUNCATED AT 250 WORDS)

Substance P (SP) and neurokinin A (NKA) in developing submandibular glands of the rat

The effect of isoprenaline, carbachol, substance P (SP) and neurokinin A (NKA) on peroxidase and total protein secretion was studied in the developing postnatal submandibular glands of the rat using in vitro methods. Submandibular glands of 1, 5, 12 and 30 day-old rats were stimulated by 10(-5) M isoprenaline and carbachol, and 10(-6) M SP and NKA. The stimulatory effects of these compounds were compared to the basic release of peroxidase and total amount of protein from submandibular gland fragments in incubation solution with no added transmitter substances. Indirect immunohistochemical methods were used to study these developing glands from SP- and NKA-immunoreactive (IR) nerve fibers. The distributions of SP-IR and NKA-IR nerve fibers closely resembled each other, being most abundantly spread around the developing acini and ducts. The number of these fibers was high on the 1st, 5th and 12th days, but was decreased on the 30th day. On peroxidase release, isoprenaline was the most effective, causing a maximal response of 47 times the basic release on the first postnatal day, after which it gradually decreased. The effects of carbachol, SP and NKA on peroxidase release were clearly weaker and, unlike isoprenaline, their strongest response was on the 5th postnatal day (carbachol, 4.3; SP 5.2; NKA, 4.5). The total protein secretion effect patterns of the studied substances resembled each other more, showing their strongest response on the 5th day (isoprenaline, 5.0; carbachol, 4.5; SP, 4.2; NKA, 3.4) and decreasing thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)

Production and characterization of a monoclonal antibody against human calcitonin gene-related peptide (CGRP) and its immunohistochemical application to salivary glands

A monoclonal antibody (mAb), 129CD8 was raised against a C-terminal fragment (aa28-37) of alpha-human calcitonin gene-related peptide (CGRP) coupled to bovine serum albumin. The specificity of the monoclonal antibody 129CD8 was corroborated by dot immunobinding experiments, enzyme-linked immunoassay and immunostaining of tissue sections. In vitro studies showed that the mAb 129CD8 readily recognized the fragment 28-37 of alpha-human CGRP and to a slightly lesser degree whole alpha-human CGRP and the fragments containing the C-terminal part of the molecule. The mAb 129CD8 also recognized the beta-human CGRP but not the alpha-rat CGRP. The mAb 129CD8 did not react with substance P, katacalcin, calcitonin, amylin or fragments of alpha-human CGRP lacking the C-terminal part of the molecule. Immunocytochemical staining was performed on human skin, guinea-pig thyroid and salivary glands and the trigeminal ganglion, and rat thyroid gland. Our findings demonstrate, in keeping with previous studies, that in human skin, nerve fibres containing CGRP immunoreactivity are found in both epidermis and dermis. In accordance with previous investigators, the Merkel cells were immunoreactive for CGRP. In the guinea-pig and rat thyroid gland CGRP immunoreactivity was localized in the C-cells. The distribution of CGRP immunoreactivity in the guinea-pig salivary glands is different from that previously reported for rat salivary glands. In the guinea-pig trigeminal ganglion, CGRP immunoreactivity was localized mainly in small-sized neurons and fibres traversing the ganglion.(ABSTRACT TRUNCATED AT 250 WORDS)