The contribution of inflammatory astrocytes to BBB impairments in a brain-chip model of Parkinson's disease

Astrocyte dysfunction has previously been linked to multiple neurodegenerative disorders including Parkinson's disease (PD). Among their many roles, astrocytes are mediators of the brain immune response, and astrocyte reactivity is a pathological feature of PD. They are also involved in the formation and maintenance of the blood-brain barrier (BBB), but barrier integrity is compromised in people with PD. This study focuses on an unexplored area of PD pathogenesis by characterizing the interplay between astrocytes, inflammation and BBB integrity, and by combining patient-derived induced pluripotent stem cells with microfluidic technologies to generate a 3D human BBB chip. Here we report that astrocytes derived from female donors harboring the PD-related LRRK2 G2019S mutation are pro-inflammatory and fail to support the formation of a functional capillary in vitro. We show that inhibition of MEK1/2 signaling attenuates the inflammatory profile of mutant astrocytes and rescues BBB formation, providing insights into mechanisms regulating barrier integrity in PD. Lastly, we confirm that vascular changes are also observed in the human postmortem substantia nigra of both males and females with PD.

Isolation and characterization of KDML105 aromatic rice rhizobacteria producing indole-3-acetic acid: impact of organic and conventional paddy rice practices

Indole-3-acetic acid (IAA) synthesis is a major property of rhizosphere bacteria. The IAA-producing ability of rhizobacteria may be influenced by agricultural management. We therefore evaluated the IAA-producing potential of rhizobacteria isolated during organic rice farming (ORF) and conventional rice farming (CRF) in Thung Kula Rong Hai areas of Thailand. The results indicated that ORF gave a significantly higher percentage of IAA producers (95·8%) than CRF (69·9%). The average IAA values of the ORF isolates were around two times higher than those of the CRF isolates both in the absence (12·8 and 5·8 μg IAA ml^-1 , respectively) and presence of L-tryptophan (L-Trp) (35·2 and 17·2 μg IAA ml^-1 , respectively). The 16S rRNA gene sequence analysis indicated that the 23 selected isolates belonged to 8 different genera-Sinomonas sp., Micrococcus sp., Microbacterium sp., Fictibacillus sp., Bacillus sp., Burkholderia sp., Leclercia sp. and Enterobacter sp. Interestingly, only three ORF isolates, i.e. ORF15-20 (Micrococcus sp.), ORF15-21 (Sinomonas sp.) and ORF15-23 (Sinomonas sp.), exhibited high IAA production ability without L-Trp (128·5, 160·8 and 174·7 μg IAA ml^-1 , respectively). Meanwhile, a slight decrease in IAA production with L-Trp was noticed, suggesting that the L-Trp was not used for the IAA synthesis of these isolates. Biopriming with rhizobacterial isolates significantly enhanced the rate of germination of KDML 105 rice seeds compared to the control.

Individual Treatment Progress Predicts Satisfaction With Transition-Related Care for Youth With Gender Dysphoria: A Prospective Clinical Cohort Study

BACKGROUND

The number of adolescents presenting with gender dysphoria (GD) in healthcare services has increased significantly, yet specialized services offering transition-related care (TRC) for trans youth is lacking.

AIM

To investigate satisfaction with TRC, regret, and reasons for (dis)satisfaction with transition-related medical interventions (TRMIs) in trans adolescents who had presented to the Hamburg Gender Identity Service for children and adolescents (Hamburg GIS).

METHODS

Data were collected from a clinical cohort sample of 75 adolescents and young adults diagnosed with GD (81% assigned female at birth) aged 11 to 21 years (M = 17.4) at baseline and follow-up (on a spectrum of ongoing care, on average 2 years after initial consultation). To determine progress of the youth's medical transitions, an individual treatment progress score (ITPS) was calculated based on number of desired vs received TRMIs.

OUTCOMES

Main outcome measures were satisfaction with TRC at the time of follow-up, ITPS, social support, reasons for regret and termination of TRC, and (dis)satisfaction with TRMIs.

RESULTS

Participants underwent different stages of TRMIs, such as gender-affirming hormone treatment or surgeries, and showed overall high satisfaction with TRC received at the Hamburg GIS. Regression analysis indicated that a higher ITPS (an advanced transition treatment stage) was predictive of higher satisfaction with TRC. Sex assigned at birth, age, and time since initial consultation at the clinic showed no significant effects for satisfaction with TRC, while degree of social support showed a trend. No adolescents regretted undergoing treatment at follow-up. Additional analysis of free-text answers highlighted satisfaction mostly with the physical results of TRMI.

CLINICAL IMPLICATIONS

Because youth were more satisfied with TRC when their individual transition (ITPS) was more progressed, treatment should start in a timely manner to avoid distress from puberty or long waiting lists.

STRENGTHS AND LIMITATIONS

This study is one of the first to report on treatment satisfaction among youth with GD from Europe. The ITPS allowed for a more detailed evaluation of TRMI wishes and experiences in relation to satisfaction with TRC and may close a gap in research on these treatments in adolescent populations. However, all participants were from the same clinic, and strict treatment eligibility criteria may have excluded certain trans adolescents from the study. Low identification rates with non-binary identities prevented comparisons between non-binary and binary genders.

CONCLUSION

The study highlights the role of TRMI and individual treatment or transition progress for youth's overall high satisfaction with TRC received at the Hamburg GIS. Nieder TO, Mayer TK, Hinz S, et al. Individual Treatment Progress Predicts Satisfaction With Transition-Related Care for Youth With Gender Dysphoria: A Prospective Clinical Cohort Study. J Sex Med 2021;18:632-645.

Impaired cognitive self-awareness mediates the association between alexithymia and excitation/inhibition balance in the pgACC

BACKGROUND

Previous research showed that automatic emotion regulation is associated with activation of subcortical areas and subsequent feedforward processes to cortical areas. In contrast, cognitive awareness of emotions is mediated by negative feedback from cortical to subcortical areas. Pregenual anterior cingulate cortex (pgACC) is essential in the modulation of both affect and alexithymia. We considered the interplay between these two mechanisms in the pgACC and their relationship with alexithymia.

METHOD

In 68 healthy participants (30 women, age = 26.15 ± 4.22) we tested associations of emotion processing and alexithymia with excitation/inhibition (E/I) balance represented as glutamate (Glu)/GABA in the pgACC measured via magnetic resonance spectroscopy in 7 T.

RESULTS

Alexithymia was positively correlated with the Glu/GABA ratio (N = 41, p = 0.0393). Further, cognitive self-awareness showed an association with Glu/GABA (N = 52, p = 0.003), which was driven by a correlation with GABA. In contrast, emotion regulation was only correlated with glutamate levels in the pgACC (N = 49, p = 0.008).

CONCLUSION

Our results corroborate the importance of the pgACC as a mediating region of alexithymia, reflected in an altered E/I balance. Furthermore, we could specify that this altered balance is linked to a GABA-related modulation of cognitive self-awareness of emotions.

Association of exposure to manganese and iron with striatal and thalamic GABA and other neurometabolites - Neuroimaging results from the WELDOX II study

OBJECTIVE

Magnetic resonance spectroscopy (MRS) is a non-invasive method to quantify neurometabolite concentrations in the brain. Within the framework of the WELDOX II study, we investigated the association of exposure to manganese (Mn) and iron (Fe) with γ-aminobutyric acid (GABA) and other neurometabolites in the striatum and thalamus of 154 men.

MATERIAL AND METHODS

GABA-edited and short echo-time MRS at 3T was used to assess brain levels of GABA, glutamate, total creatine (tCr) and other neurometabolites. Volumes of interest (VOIs) were placed into the striatum and thalamus of both hemispheres of 47 active welders, 20 former welders, 36 men with Parkinson's disease (PD), 12 men with hemochromatosis (HC), and 39 male controls. Linear mixed models were used to estimate the influence of Mn and Fe exposure on neurometabolites while simultaneously adjusting for cerebrospinal fluid (CSF) content, age and other factors. Exposure to Mn and Fe was assessed by study group, blood concentrations, relaxation rates R1 and R2* in the globus pallidus (GP), and airborne exposure (active welders only).

RESULTS

The median shift exposure to respirable Mn and Fe in active welders was 23μg/m3 and 110μg/m3, respectively. Airborne exposure was not associated with any other neurometabolite concentration. Mn in blood and serum ferritin were highest in active and former welders. GABA concentrations were not associated with any measure of exposure to Mn or Fe. In comparison to controls, tCr in these VOIs was lower in welders and patients with PD or HC. Serum concentrations of ferritin and Fe were associated with N-acetylaspartate, but in opposed directions. Higher R1 values in the GP correlated with lower neurometabolite concentrations, in particular tCr (exp(β)=0.87, p<0.01) and choline (exp(β)=0.84, p=0.04). R2* was positively associated with glutamate-glutamine and negatively with myo-inositol.

CONCLUSIONS

Our results do not provide evidence that striatal and thalamic GABA differ between Mn-exposed workers, PD or HC patients, and controls. This may be due to the low exposure levels of the Mn-exposed workers and the challenges to detect small changes in GABA. Whereas Mn in blood was not associated with any neurometabolite content in these VOIs, a higher metal accumulation in the GP assessed with R1 correlated with generally lower neurometabolite concentrations.

Frequency of Norovirus in stool samples from patients with gastrointestinal symptoms in Switzerland

To determine the frequency of sporadic community-acquired Norovirus (NV) infection in the German-speaking part of Switzerland, an evaluation of gastroenteritis cases seen in physicians' practices between July 2001 and July 2003 was conducted. A total of 699 stool specimens documented to be free of common bacterial pathogens was screened for the presence of NV by RT-PCR. NV was detected in 125 (17.9%) of these specimens. In the seasonal analysis, the highest rate of NV-positive samples (38.3%) was found between January and March 2002. After July 2002, the study was expanded to additionally test for NV in stool samples containing a known bacterial pathogen. Among 132 such specimens, NV was detected in only one. This suggests that NV mixed-infections are playing a marginal role in Switzerland.

Semaphorin4F interacts with the synapse-associated protein SAP90/PSD-95

Semaphorins are a family of secreted and membrane-associated proteins involved in growth cone guidance during development. Here, we describe the interaction of Semaphorin4F (Sema4F) with the post-synaptic density protein SAP90/PSD-95. Using the yeast two-hybrid system and coprecipitation assays we were able to show an interaction between the extreme C-terminus of Sema4F and the PDZ domains of SAP90/PSD-95. Heterologous coexpression of a chimeric EphrinB1/Semaphorin4F protein with SAP90/PSD-95 in COS cells leads to translocation of SAP90/PSD-95 from the cytosol to the membrane. Deletion analysis shows that this translocation activity of Sema4F is completely dependent on the presence of the last three C-terminal amino acids. In addition, Sema4F immunoreactivity is present in synaptosome fractions and enriched in post-synaptic density fractions. Consistently, in cultured hippocampal neurons, we demonstrate punctate colocalization of Sema4F and SAP90/PSD-95 in dendrites, furthermore we found colocalization of Sema4F with synapsin1 suggesting a synaptic localization. Our data implicate a new functional context for semaphorins at glutamatergic synapses.

The Adenomatous Polyposis Coli-protein (APC) interacts with the protein tyrosine phosphatase PTP-BL via an alternatively spliced PDZ domain

Mutations of the tumor suppressor protein APC (Adenomatous Polyposis Coli) are linked to familiar and sporadic human colon cancer. Here we describe a novel interaction between the APC protein and the protein tyrosine phosphatase PTP-BL carrying five PDZ protein-protein interaction domains. Exclusively, the second PDZ domain (PDZ2) of PTP-BL is binding to the extreme C-terminus of the APC protein, as determined by yeast two-hybrid studies. Using surface plasmon resonance analysis we established a dissociation constant (K(D)) of 8.1 x 10(-9) M. We find that a naturally occurring splice insertion of five amino acids (PDZ2b) abolishes its binding affinity to the APC protein. The in vivo interaction between PTP-BL and the APC protein was shown by coprecipitation experiments in transfected COS cells. Furthermore, in cultured epithelial Madine Carnine Kidney cells the subcellular colocalization was demonstrated for the nucleus and also for the tips of cellular extensions. The interaction of the APC protein with a protein tyrosine phosphatase may indirectly modulate the steady state levels of tyrosine phosphorylations of associated proteins, such as beta-catenin playing a major role in the regulation of cell division, migration and cell adhesion.

[Artifact detection and signal reconstruction in the pupillogram]

Just as the EEG reflects different wake and sleep stages, changes in pupil dynamics reflecting different levels of vigilance are also to be found. The literature contains numerous reports on experimental set-ups for the recording of the pupillogram. Interesting methods of signal processing are to be found in [7] and [5]. Currently, such recordings are being used to check the success of sleep therapy. A problem that still needs solving is the optimal handling of artifacts caused by blinking. The present article proposes a procedure for artifact detection by back-propagation networks, and subsequent reconstruction of the signal by an AR model. Estimation of the signal is first demonstrated by a test signal, and then by a corrupted pupillogram.

Helicobacter pylori cadA encodes an essential Cd(II)-Zn(II)-Co(II) resistance factor influencing urease activity

Inactivation of Helicobacter pylori cadA, encoding a putative transition metal ATPase, was only possible in one of four natural competent H. pylori strains, designated 69A. All tested cadA mutants showed increased growth sensitivity to Cd(II) and Zn(II). In addition, some of them showed both reduced 63Ni accumulation during growth and no or impaired urease activity, which was not due to lack of urease enzyme subunits. Gene complementation experiments with plasmid (pY178)-derived H. pylori cadA failed to correct the deficiencies, whereas resistance to Cd(II) and Zn(II) was restored. Moreover, pY178 conferred increased Co(II) resistance to both the cadA mutants and the wild-type strain 69A. Heterologous expression of H. pylori cadA in an Escherichia coli zntA mutant resulted in an elevated resistance to Cd(II) and Zn(II). Expression of cadA in E. coli SE5000 harbouring H. pylori nixA, which encodes a divalent cation importer along with the H. pylori urease gene cluster, led to about a threefold increase in urease activity compared with E. coli control cells lacking the H. pylori cadA gene. These results suggest that H. pylori CadA is an essential resistance pump with ion specificity towards Cd(II), Zn(II) and Co(II). They also point to a possible role of H. pylori CadA in high-level activity of H. pylori urease, an enzyme sensitive to a variety of metal ions.

Properties and function of the P type ion pumps cloned from Helicobacter pylori

Three distinct P type pumps were cloned from H. pylori 69A. Two of these pumps, ATPase 439 and ATPase 948 (CopA), were isolated by gene library screening using DNA oligonucleotide primers. Amino acid similarities found for the predicted proteins were about 50% to Cd2+/Cu2+ pumps. Gene disruption mutagenesis rendered the H. pylori knockout mutants more sensitive to Zn2+ and Cd2+ (ATPase 439) or Cu2+ (CopA). Some of the ATPase 439-deficient mutants were negative for urease activity while the majority of the mutants remained positive. Functional diversity of the pumps was also reflected by the ion affinities found for N-terminal peptides of CopA to Cu2+ and of ATPase 439 to Ni2+, Cu2+ and CO2+. The membrane domain of the two pumps were experimentally shown to consist of eight membrane spans. When ATPase 439 was expressed under control of a tac promoter in Escherichia coli, vanadate-sensitive phosphate accumulation was observed cytochemically along the membrane of the host cells. The third P type pump (ATPase 115) which also exhibited homology to transition metal ATPase was identified by sequencing a library of H. pylori membrane genes. The hydropathy plot of this pump was very similar to the former H. pylori ATPases whereas the N-terminal ion binding region was distinct. It was concluded that, in H. pylori, the presence of three transition metal ATPases with distinct ion specificity contributes to the adaptive mechanisms for gastric survival.

The effects of hydrophilic to hydrophobic surface mutations on the denatured state of iso-1-cytochrome c: investigation of aliphatic residues

A series of hydrophilic to hydrophobic surface mutations were prepared at the highly solvent-exposed lysine 73 of iso-1-cytochrome c to assess the ability of such mutants to affect the energetics of the denatured state. In this report, the aliphatic hydrophobics (leucine, isoleucine, valine, alanine, glycine) were studied. The thermodynamic stability of each of these mutants was determined by guanidine hydrochloride denaturation. Both the free energy of unfolding in the absence of denaturant, delta GouH2O, and the slope, m, of a plot of the free energy of unfolding, delta Gou, versus [guanidine hydrochloride] show significant negative correlations with the 1-octanol to water transfer free energy, delta Gtr, of the amino acid side chain at position 73. A negative correlation with hydrophobicity is consistent with these mutants leading to more extensive hydrophobic clustering in the denatured state, consistent with the predictions of heteropolymer theory for compact denatured states; an effect operating on the native state energetics should produce a positive correlation of delta GouH2O with hydrophobicity. Infrared amide I spectroscopy indicated native state structural perturbations for the glycine 73 and isoleucine 73 mutants. A moderate correlation of delta GouH2O was also found with alpha-helix propensity, suggesting that both hydrophobic effects acting on the denatured state and alpha-helix propensity are affecting the delta GouH2O values for these mutants.

[Improved learning capacity and discrimination performance of neural networks in pattern recognition of biosignals]

Pattern recognition was an important goal in the early work on artificial neural networks. Without arousing dramatic speculation, the paper describes, how a "natural" method of dealing with the configuration of the input layer can considerably improve learning behaviour and classification rate of a modified multi-layered perception with backpropagation of the error learning rule. Using this method, recognition of complex patterns in electrophysiological signals can be performed more accurately, without rules or complicated heuristic procedures. The proposed technique is demonstrated using recognition of the J-point in the ECG as an example.

[Which are the most frequent enteropathogenic parasites found in clinical practice?]

Infectious diarrhea is seen with increasing frequency in general practice. The main reason is growing tourism in countries with conditions of public health different from ours, where the incidence of enteropathogenic parasites is higher. To obtain an overview of these parasites, the results of 23,276 stool samples from patients in general practice throughout Switzerland were analyzed. Protozoa were found in 32% of samples (4.6% pathogenic protozoa, 24% facultative pathogenic protozoa and 3.4% apathogenic protozoa). Helminths were demonstrated in 2.9% of stool samples. The helminth spectrum covered 15 types, with Trichuris trichiuria predominating (one third). 8% of the Swiss population travel every year to areas with a higher diarrhea incidence. A proportion of these subjects constitute a health risk on their return to Switzerland. They chiefly consist of people working in, or living with someone working in, the food industry. Specific parasitologic diagnosis of diarrhea contributes significantly to reducing this risk.

[Sex- and age-related differences in blood pressure response to local muscular work during noise]

During noise exposure (90 dB [A]) and during local muscular work (30% MVC) combined with noise (90 db [A]) the blood pressure was measured in 20 men and 20 women (20-29 years; 30-39 years). In the group of younger subjects the blood pressure was taken also during the recovery period of 60 minutes. Age- and sex-related differences in blood pressure response were observed not only during noise exposure but also during combined exposure. The different return of the diastolic blood pressure to the resting value after the period of combined exposure referred to sex-related differences in the response of the cardiovascular system during the recovery period, too.

[Local muscle work and noise and their effect on the amplitude of the finger pulse]

The finger pulse amplitude of 10 healthy men (aged 20 to 30 years) was measured during noise (70, 80 and 90 dBA) and combined exposure (local muscular work with 30% MVC and noise with 70, 80 or 90 dBA) and during a recovery phase of 60 min. The finger pulse amplitude was reduced only during noise exposure with 90 dBA and was increased during the combined exposures. A continuous decrease of the finger pulse amplitude was observed during the recovery phases. Differences between noise exposure and combined exposure do not exist. The findings were discussed as the risk of hypertension in workers exposed to noise.

[Clinico-neurologic long-term results following surgery of intervertebral disk displacement]

Of the 1732 patients undergoing disk surgery in the period 1971-1980, a sample of 245 was selected, and data gathered prior to their operations compared with data gathered two to twelve years after the operation. Analyses was made of the specific character of pain, the state of the reflexes, motor and sensory failure, Lasègue's sign, finger-ground-distance Disorders of bladder and Rectum, and the patients' subjective judgement of their complaints. The possibility of improvement in the various findings is discussed.

Placebo-like effects of education about behavior therapy

To learn about behavior therapy, undergraduate students in abnormal psychology treated self-selected personal problems, with the aid of course lectures, homework, and texts. Target behavioral problems were usually alleviated, but success did not depend on whether recommended treatment methods were used. Self-ratings of project success were related to objective measures of improvement; but they were also related to factors associated with positive expectations and to social, instructional, and help-seeking variables. Our pedagogical procedures produced placebo-like effects similar to those seen in therapeutic settings.

Cardiovascular effects of single doses of the antidepressants amitriptyline and lofepramine in healthy subjects

In a placebo-controlled double blind study, single oral doses of lofepramine (140 mg and 210 mg) and amitriptyline (100 mg and 150 mg) were given to 5 healthy volunteers. Heart rate, blood pressure, systolic time intervals, and electrical impedance cardiogram were recorded in supine and upright position for 8 hours after drug administration. In addition, plasma drug concentrations were measured simultaneously. Amitriptyline caused a more pronounced increase in heart rate, especially under orthostatic stress, than did lofepramine. Both drugs reduced total peripheral resistance; amitriptyline's effect was greater. A rise in blood pressure (supine position) and shortening of the electromechanical systole under lofepramine indicated an improvement of cardiac performance. In contrast amitriptyline, particularly, in the upright position, lowered blood pressure and lengthened electromechanical systole. Since both drugs have a comparable antidepressant activity, lofepramine is suggested to induce fewer untoward cardiovascular reactions than amitriptyline.

The effect of L-5-hydroxytryptophan on self-mutilatin in Lesch-Nyhan disease: a negative report

Four patients with Lesch-Nyhan disease were treated with L-5-hydroxytryptophan, alone, or in combination with carbidopa, and their effect on self-mutilatory behavior was compared to that observed during periods in which placebo was administered. Observation periods were carefully standardized because of the ease with which patient-observer interactions can influence the behavior of the Lesch-Nyhan patient. The dosage level was sufficient to produce undesirable side-effects (diarrhea and vomiting). No effect on self-mutilation was observed under test conditions in the hospital or in the natural environment of the home. These results contrast with previous beneficial effects reported by others.