Summer temperatures reach the thermal tolerance threshold of photosynthetic decline in temperate conifers

Climate change-related environmental stress has been recognized as a driving force in accelerating forest mortality over the last decades in Central Europe. Here, we aim to elucidate the thermal sensitivity of three native conifer species, namely Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and silver fir (Abies alba), and three non-native species, namely Austrian pine (Pinus nigra), Douglas fir (Pseudotsuga menziesii) and Atlas cedar (Cedrus atlantica). Thermal sensitivity, defined here as a decline of the maximum quantum yield of photosystem II (F_v /F_m ) with increasing temperature, was measured under varying levels of heat stress and compared with the turgor loss point (π_tlp ) as a drought resistance trait. We calculated three different leaf thermotolerance traits: the temperature at the onset (5%) of the F_v /F_m decline (T5), the temperature at which F_v /F_m was half the maximum value (T50) and the temperature at which only 5% F_v /F_m remained (T95). T5 ranged from 38.5 ± 0.8 °C to 43.1 ± 0.6 °C across all species, while T50 values were at least 9 to 11 degrees above the maximum air temperatures on record for all species. Only Austrian pine had a notably higher T5 value than recorded maximum air temperatures. Species with higher T5 values were characterized by a less negative π_tlp compared to species with lower T5. The six species could be divided into 'drought-tolerant heat-sensitive' and 'drought-sensitive heat-tolerant' groups. Exposure to short-term high temperatures thus exhibits a considerable threat to conifer species in Central European forest production systems.

Telemedical monitoring and coaching improves survival and hospitalisation rates in heart failure

Aims

To investigate the effectiveness of a combined telemonitoring and telecoaching programme for chronic heart failure patients at high risk for hospitalisation compared to usual care in a real life setting. The applied telehealth programme consisted of regular individualised telecoaching sessions as well as daily remote telemonitoring of heart failure signs and symptoms.

Methods

Between January 2018 and September 2020, 6,065 heart failure patients were enrolled in a combined telehealth programme and retrospectively compared to a propensity matched usual care group (n=6,065). All participants were members of a statutory health insurance. Median follow-up was 442 days (IQR 309–681). Endpoints were all cause mortality, number and duration of hospitalisations.

Results

After 1 year the combined telecoaching and telemonitoring programme significantly reduced all-cause mortality probability compared to usual care (11.0 vs. 5.8%, p<0.001). The corresponding number-needed to treat to prevent one death in one year was 19.3. In addition, the number of hospitalisations for heart failure (17.9 vs. 21.8 per 100 patient years, p<0.001) and all cause hospitalisations (129.0 vs. 133.2, p=0.015), as well as their duration (2.0 vs. 2.6 days per year p<0.001, and 12.0 vs. 13.4 days per year p>0.001, respectivel y) were significantly lower in the telehealth group than in the usual care group.

Conclusion

In ambulatory heart failure patients at high risk for hospitalisation, a combined telemonitoring and telecoaching programme led to a reduction of heart failure hospitalisations and all-cause mortality compared to standard care.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Health Care Systems GmbH (HCSG), Pullach i. Isartal

Predicting the need of aortic valve surgery in patients with chronic aortic regurgitation: a comparison between cardiovascular magnetic resonance imaging and transthoracic echocardiography

To compare the ability of cardiac magnetic resonance tomography (CMR) and transthoracic echocardiography (TTE) to predict the need for valve surgery in patients with chronic aortic regurgitation on a mid-term basis. 66 individuals underwent assessment of aortic regurgitation (AR) both in CMR and TTE between August 2012 and April 2017. The follow-up rate was 76% with a median of 5.1 years. Cox proportional hazards method was used to assess the association of the time-to-aortic-valve-surgery, including valve replacement and reconstruction, and imaging parameters. A direct comparison of most predictive CMR and echocardiographic parameters was performed by using nested-factor-models. Sixteen patients (32%) were treated with aortic valve surgery during follow-up. Aortic valve insufficiency parameters, both of echocardiography and CMR, showed good discriminative and predictive power regarding the need of valve surgery. Within all examined parameters AR gradation derived by CMR correlated best with outcome [χ² = 27.1; HR 12.2 (95% CI: 4.56, 36.8); (p < 0.0001)]. In direct comparison of both modalities, CMR assessment provided additive prognostic power beyond echocardiographic assessment of AR but not vice versa (improvement of χ² from 21.4 to 28.4; p = 0.008). Nested model analysis demonstrated an overall better correlation with outcome by using both modalities compared with using echo alone with the best improvement in the moderate to severe AR range with an echo grade II out of III and a regurgitation fraction of 32% in CMR. This study corroborates the capability of CMR in direct quantification of AR and its role for guiding further treatment decisions particularly in patients with moderate AR in echocardiography.

Middle Meningeal Artery Embolization Using Combined Particle Embolization and n-BCA with the Dextrose 5% in Water Push Technique for Chronic Subdural Hematomas: A Prospective Safety and Feasibility Study

BACKGROUND AND PURPOSE

Embolization of the middle meningeal artery for treatment of refractory or recurrent chronic subdural hematomas has gained momentum during the past few years. Little has been reported on the use of the n-BCA liquid embolic system for middle meningeal artery embolization. We present the technical feasibility of using diluted n-BCA for middle meningeal artery embolization.

MATERIALS AND METHODS

We sought to examine the safety and technical feasibility of the diluted n-BCA liquid embolic system for middle meningeal artery embolization. Patients with chronic refractory or recurrent subdural hematomas were prospectively enrolled from September 2019 to June 2020. The primary outcome was the safety and technical feasibility of the use of diluted n-BCA for embolization of the middle meningeal artery. The secondary end point was the efficacy in reducing hematoma volume.

RESULTS

A total of 16 patients were prospectively enrolled. Concomitant burr-hole craniotomies were performed in 12 of the 16 patients. Two patients required an operation following middle meningeal artery embolization for persistent symptoms. The primary end point was met in 100% of cases in which there were no intra- or postprocedural complications. Distal penetration of the middle meningeal artery branches was achieved in all the enrolled cases. A 7-day post-middle meningeal artery embolization follow-up head CT demonstrated improvement (>50% reduction in subdural hematoma volume) in 9/15 (60%) patients, with 6/15 (40%) showing an unchanged or stable subdural hematoma. At day 21, available CT scans demonstrated substantial further improvement (>75% reduction in subdural hematoma volume).

CONCLUSIONS

Embolization of the middle meningeal artery using diluted n-BCA and ethiodized oil (1:6) is safe and feasible from a technical standpoint. The use of a dextrose 5% bolus improves distal penetration of the glue.

Improved self- and external assessment of the clinical abilities of medical students through structured improvement measures in an internal medicine bedside course

BACKGROUND

Bedside courses are of outstanding importance when training medical students. The fact that less and less teaching is taking place nowadays at the patient's bedside makes it all the more important that the available time be put to effective use. The aim of this study was to check whether structured improvement measures in the course (scripts, lecturer briefing, e-learning cases) would improve the abilities of the students on the basis of a subjective self-assessment as well as an external assessment by the lecturers with respect to clinical abilities.

METHODS

Bedside teaching takes place in the fourth study year in the Medical Clinics of the TU Munich. Both students and lecturers had the chance to hand in an anonymous, quantitative self- and external assessment of the clinical abilities of the students (German grading system) after every course date. This assessment took place online in the three categories "Medical history & examination", "Diagnosis" and "Therapy". An overall period of four semesters, each with 6 course dates, was investigated. After two of the total of four semesters in the study, the course was changed by introducing scripts, lecturer briefing as well as interactive e-learning cases. The self- and external assessment was compared both within the semester (date 1-3: A; date 4-6: B), during the course as well as before and after introducing the improvement measures ("before" (T0): SS 2012, SS 2013, "after" (T1): WS 2013/2014, SS 2014).

RESULTS

There was a significant improvement in one's own abilities on the basis of the self-assessment within each semester when comparing the first (A) and the last (B) course dates. Moreover, there was a significant improvement in the performances in all three categories when T0 was compared with T1, from both the point of view of the students ("Medical history & examination": T0 =2.5±0.9, T1=2.2±0.7, pp<0.001; "Diagnosis" T0=3.1±1.0, T1=2.8 ±0.9, pp<0.001; "Therapy": T0=3.8±1.3, T1=3.5±1.2, pp<0.018) and in two of the three categories from the point of view of the lecturers ("Diagnosis": T0=3.0±1.0, T1=2.7±0.7, p.=0.028; "Therapy": T0=3.8±1.1, T1=3.1±1.0, p<0.001).

SUMMARY

The structured measures to improve the course including the interactive e-learning cases could have contributed to improved practical abilities with respect to the medical history and examination techniques as well as diagnostic and therapeutic thinking. The external evaluation by lecturers confirmed the improvement with respect to the diagnostic and therapeutic abilities. They only saw no dynamic change in the student's taking histories and clinical examinations.

Genotype-phenotype correlations between GBA mutations and Parkinson disease risk and onset

BACKGROUND

Mutations in GBA and LRRK2 genes have been implicated in Parkinson disease (PD), particularly in Ashkenazi Jews.

METHODS

An Israeli Ashkenazi cohort of 420 patients with PD, 333 elderly controls, and 3,805 young controls was screened for eight GBA mutations, which are associated with mild (N370S, R496H) and severe (84GG, IVS2 + 1, V394L, D409H, L444P, RecTL) Gaucher disease. Patients with PD and elderly controls were also genotyped for LRRK2 G2019S.

RESULTS

GBA carrier frequency was 17.9% in patients with PD compared to 4.2% in elderly and 6.35% in young controls. The proportion of severe mutation carriers among PD patient GBA carriers was 29% compared to 7% among young controls. Severe and mild GBA mutations increased the risk of developing PD by 13.6- and 2.2-fold, and affected the average age at PD onset (AAO), 55.7 and 57.9 years, compared to 60.7 years in patients without known GBA or LRRK2 mutations.

CONCLUSIONS

These data demonstrate genotype-phenotype correlations between different GBA mutations and Parkinson disease (PD) risk and AAO in Ashkenazi Jews. Additionally, an earlier AAO was observed in LRRK2 G2019S carrier PD patients. Finally, these data demonstrate that a surprisingly high frequency, more than one third of our patient population, carried a mutation in GBA or LRRK2.

The LRRK2 G2019S mutation in Ashkenazi Jews with Parkinson disease: is there a gender effect?

BACKGROUND

Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most common genetic determinant of Parkinson disease (PD) identified to date, and have been implicated in both familial and sporadic forms of the disease. The G2019S change in LRRK2 exon 41 has been associated with disease at varying frequencies in Asian, European, North American, and North African populations, and is particularly prevalent among Ashkenazi Jews.

METHODS

We assessed the occurrence of the LRRK2 G2019S, I2012T, I2020T, and R1441G/C/H mutations in our cohort of Jewish Israeli patients with PD, and determined the LRRK2 haplotypes in 76 G2019S-carriers detected and in 50 noncarrier Ashkenazi patients, using six microsatellite markers that span the entire gene.

RESULTS

Only the G2019S mutation was identified among our patients with PD, 14.8% in the Ashkenazi and 2.7% in the non-Ashkenazi patients, and in 26% and 10.6% of the Ashkenazi familial and apparently sporadic cases. The carrier frequencies in the Ashkenazi and non-Ashkenazi control samples were 2.4% and 0.4%. A common shared haplotype was detected in all non-Ashkenazi and half-Ashkenazi carriers and in all full-Ashkenazi carriers tested, except two. Women and patients with a positive family history of PD were significantly over-represented among the G2019S mutation carriers. Age at disease onset was similar in carriers and noncarriers.

CONCLUSIONS

Our data suggest that the LRRK2 G2019S mutation plays an important role in the causality of familial and sporadic Parkinson disease (PD) in Israel and that gender affects its frequency among patients. Although testing symptomatic patients may help establish the diagnosis of PD, the value of screening asymptomatic individuals remains questionable until the penetrance and age-dependent risk of this mutation are more accurately assessed, and specific disease prevention or modifying interventions become available.

Pathologic features of the placenta in women with severe pregnancy complications and thrombophilia

OBJECTIVE

To compare placental pathology between women with and without thrombophilia who had severe preeclampsia, intrauterine growth retardation, severe abruptio placentae, or stillbirth.

METHODS

After delivery, 68 women with singleton pregnancies with one of the above complications were evaluated for an inherited thrombophilia: factor V Leiden, methylenetetrahydrofolate reductase and prothrombin gene mutation, and deficiencies of protein S, protein C, and antithrombin III. Thirty-two women were thrombophilic (group A), and 36 women were not (group B). There was no difference in maternal age, parity, and type of pregnancy complication. A single pathologist examined each placenta.

RESULTS

The gestational age at delivery, birth weight, and placental weight were significantly lower in group A. Three parameters showed significant differences between the groups: thrombophilic women had a higher number of villous infarcts (P <.01), more multiple infarcts (P <.05), and a higher incidence of placentas with fibrinoid necrosis of decidual vessels (P <.05).

CONCLUSION

Placentas of women with severe complications and thrombophilia have an increased rate of vascular lesions.

The prevalence and nosocomial acquisition of Clostridium difficile in elderly hospitalized patients

Rectal swabs obtained from 10 of 49 chronic-care geriatric patients were positive for Clostridium difficile, for a prevalence rate of 20.4%. Simultaneous sampling of 29 patients in an acute geriatric ward revealed four colonized patients, for a prevalence rate of 13.7%. A prospective study of C. difficile colonization in 100 consecutive patients admitted to an acute geriatric ward was carried out. All patients were sampled upon admission and biweekly during hospitalization. Two patients (2%) were positive on admission, and 12 of the 98 initially negative patients became colonized, representing a nosocomial acquisition rate of 12.2%. A major determinant for C. difficile colonization in asymptomatic patients appears to be length of hospitalization. Previous antibiotic administration was not found to be a significant factor.

A multicenter study of outcome in systemic lupus erythematosus. II. Causes of death

Causes of death were examined for 1,103 systemic lupus erythematosus patients who were followed from 1965 to 1978 at 9 centers that participated in the Lupus Survival Study Group. A total of 222 patients (20%) died. Lupus-related organ system involvement (mainly active nephritis) and infection were the most frequent primary causes of death. Causes of death were similar throughout the followup period. Hemodialysis had little impact on the length of survival for patients with nephritis. Active central nervous system disease and myocardial infarction were infrequent causes of death. There were no deaths from malignancy.

Multiple meningeal diverticula and cysts associated with duplications of the sheaths of spinal nerve posterior roots

Multiple diverticula and cysts of the meninges were found during an anatomical dissection. They were associated with duplications of sheaths of the posterior roots of the spinal nerves. The diverticula and cysts appeared as simple flaccid corrugated dilatations of the sheaths, as ampullary expansions, as pediculated cysts, or as saccular dilatations of different sizes and locations. The duplication of the sheaths affected posterior roots of the thoracic nerves only. Some variations of the sheaths described in the literature are discussed. The possibility is considered that both conditions result from the same pathological factors in the embryo.