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21.
Introduction: A seasonal affective disorder (SAD) is a subtype of unipolar and bipolar major depressive disorders. It is characterized by its annual recurrence of depressive episodes at a particular season, mostly seen in winter and is responsible for 10–20% of the prevalence of major depressive disorders. Some pathophysiological hypotheses, such as the phase delay and the monoamine depletion hypotheses, have been postulated but the exact cause has not been fully unraveled yet. Studies on treatment for SAD in the last decade are lacking. To tackle this chronic disease, attention needs to be drawn to the gaps in this research field.

Areas covered: In this systematic review, the authors give a broad overview of the pharmacological therapy available for SAD. Also, nutritional substances fitting well with the postulated hypotheses are reviewed for the treatment and prevention of SAD. There is a specific focus on the quality of the currently performed studies.

Expert opinion: Light therapy and fluoxetine are the only proven and effective acute treatment options for SAD, while bupropion is the only registered drug for prevention of SAD. This area of research is in dire need of valid large-scale and sufficiently reproducible randomized control trials.  相似文献   

22.
Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Most patients have pathogenic autoantibodies against the acetylcholine receptor (AChR). In the last years a novel subpopulation of MG patients has been described that harbors antibodies against low-density lipoprotein receptor-related protein 4 (Lrp4), another postsynaptic neuromuscular antigen. In early-onset AChR MG (EOMG), the thymus plays an important role in immunopathogenesis, and early thymectomy is beneficial. It is still unknown if the thymus plays any role in Lrp4-MG. In this pilot study, we compared thymus samples from four patients with Lrp4-MG (one pre-treated with immunosuppressive drugs), four non-MG controls and five EOMG patients (not pretreated with immunosuppressive drugs). Immunohistochemistry of the Lrp4-MG thymi revealed normal architecture, with normal numbers and distribution of B-cells, lymphoid follicles and Hassall's corpuscles. Primary CD23+ lymphoid follicles were similarly infrequent in Lrp4-MG and control thymic sections. In none of the control or Lrp4-MG thymi did we find secondary follicles with CD10+ germinal centers. These were evident in 2 of the 5 EOMG thymi, where primary lymphoid follicles were also more frequent on average, thus showing considerable heterogeneity between patients. Even if characteristic pathological thymic changes were not observed in the Lrp4 subgroup, we cannot exclude a role for the thymus in Lrp4-MG pathogenesis, since one Lrp4-MG patient went into clinical remission after thymectomy alone (at one year follow-up) and one more improved after thymectomy in combination with immunosuppressive therapy.  相似文献   
23.
Clinical and Experimental Medicine - Vasculopathy is a crucial feature of systemic sclerosis (SSc), and Raynaud’s phenomenon (RP) and digital ulcers (DU) have a deep impact on the quality of...  相似文献   
24.
Bergantini  L  Cameli  P  d’Alessandro  M  Vagaggini  C  Refini  RM  Landi  C  Pieroni  MG  Spalletti  M  Sestini  P  Bargagli  E 《Clinical and experimental medicine》2019,19(4):487-494
Clinical and Experimental Medicine - Background The pathogenetic and regulatory roles of natural killer (NK) and natural killer T-like cells in interstitial lung diseases (ILDs), fibrotic and...  相似文献   
25.
Interferon-γ inducible protein 10 (IP-10), is a potent chemoattractant that promotes migration of monocytes and activated T-cells to inflammation foci. IP-10 is elevated in serum of patients with chronic hepatitis C virus (HCV) and tuberculosis (TB) infections, although it remains to be determined the contribution of IP-10 in restricting Mycobacterium tuberculosis (Mtb) replication. Here, we investigated the impact of IP-10 on mycobacteria replication using the ex vivo model of human whole-blood (WB) assay. In particular, we compared the levels of IP-10 upon infection with different Mtb clinical strains and species of non-tuberculous mycobacteria (NTM) and evaluated how IP-10 may contain bacterial replication. Interestingly, we observed that the inhibition of the host enzyme dipeptidyl peptidase IV (DPP-IV), which inactivates IP-10 through cleavage of two amino acids at the chemokine N-terminus, restricted mycobacterial persistence in WB, supporting the critical role of full length IP-10 in mediating an anti-Mtb response. Addition of recombinant IP-10 expressed in eukaryotic cells enhanced the anti-mycobacterial activity in WB, although no differences were observed when IP-10 containing different proportions of cleaved and non-cleaved forms of the chemokine were added. Moreover, recombinant IP-10 did not exert a direct anti-mycobacterial effect. Our results underscore the clinical relevance of IP-10 in mycobacteria pathogenesis and support the potential outcomes that may derive by targeting the IP-10/CXCR3 pathway as host directed therapies for the treatment of Mtb or NTM infections.  相似文献   
26.
27.
Intraductal carcinoma of the prostate (IDC-P) most often appears associated with high-grade invasive prostate carcinoma (PCa), where it is believed to represent retrograde spread. However, IDC-P rarely occurs as an isolated finding at radical prostatectomy or with concurrent low-grade (Grade Group 1) invasive carcinoma. We hypothesized that isolated IDC-P (iIDC-P) in these unusual cases may represent a distinct in situ lesion and molecularly profiled 15 cases. iIDC-P was characterized by copy number alteration (CNA) profiling and targeted next generation sequencing in cases with sufficient tissue (n = 7). Immunohistochemistry for PTEN and ERG was performed on the total cohort (n = 15), where areas of iIDC-P and associated invasive disease were evaluated separately (n = 9). By copy number profiling, iIDC-P alterations were similar to those previously described in high-grade invasive PCa (PTEN, RB1, and CHD1 loss; MYC gain). However, in four cases, targeted sequencing revealed a striking number of activating oncogenic driver mutations in MAPK and PI3K pathway genes, which are extraordinarily rare in conventional PCa. In addition, pathogenic mutations in DNA repair genes were found in two cases of iIDC-P (BRCA2, CHEK2, CDK12) and other known PCa-associated mutations (FOXA1, SPOP) in two cases. Overall, ERG was expressed in 7% (1/15) of the iIDC-P lesions and PTEN was lost in 53% (8/15). Discordance for ERG or PTEN status between IDC-P and the low-grade PCa was observed in five of nine cases, with intact PTEN in the invasive tumor and PTEN loss in IDC-P in four. Despite a CNA profile similar to conventional PCa, iIDC-P is enriched with potentially targetable oncogenic driver mutations in MAPK/PI3K genes. Based on PTEN and ERG status, iIDC-P is not likely a precursor to the associated low-grade invasive PCa, but represents a molecularly unique in situ tumor of unclear clinical significance. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
28.
Some species of mycobacteria have been modified to transform sterols to valuable steroid synthons. The unique cell wall of mycobacteria has been recognized as an important organelle to absorb sterols. Some cell wall inhibitors (e.g., vancomycin and glycine) have been validated to enhance sterol conversion by interfering with transpeptidation in peptidoglycan biosynthesis. Therefore, two transpeptidase genes, pbpA and pbpB, were selected to rationally modify the cell wall to simulate the enhancement effect of vancomycin and glycine on sterol conversion in a 22‐hydroxy‐23,24‐bisnorchol‐4‐ene‐3‐one (4‐HBC) producing strain (WIII). Unexpectedly, the pbpA or pbpB gene augmentation was conducive to the utilization of sterols. The pbpB augmentation strain WIII‐pbpB was further investigated for its better performance. Compared to WIII, the morphology of WIII‐pbpB was markedly changed from oval to spindle, indicating alterations of the cell wall. Biochemical analysis indicated that the altered cell wall properties of WIII‐pbpB might contribute to the positive effect on sterol utilization. The productivity of 4‐HBC was enhanced by 28% in the WIII‐pbpB strain compared to that of WIII. These results demonstrated that the modification of peptidoglycan synthesis can improve the conversion of sterols to steroid synthons in mycobacteria.  相似文献   
29.
Parasitology Research - Berberine chloride, a plant-derived isoquinoline alkaloid, has been demonstrated to have leishmanicidal activity, which is mediated by generation of a redox imbalance and...  相似文献   
30.
Introduction: Effective resuscitation with human albumin solutions is achieved with less fluid than with crystalloid solutions. However, the role of albumin in today’s critical care unit is also linked to its multiple pharmacological effects.

Areas covered: The potential clinical benefits of albumin in select populations of critically ill patients like sepsis seem related to immunomodulatory and anti-inflammatory effects, antibiotic transportation and endothelial stabilization. Albumin transports many drugs used in critically ill patients. Such binding to albumin is frequently lessened in critically ill patients with hypoalbuminemia. These changes could result in sub-optimal treatment. Albumin has immunomodulatory capacity by binding several bacterial products. Albumin also influences vascular integrity, contributing to the maintenance of the normal capillary permeability. Moreover, the albumin molecule encompasses several antioxidant properties, thereby significantly reducing re-oxygenation injury, which is especially important in sepsis. In fact, most studies of albumin administration are a combination of a degree of resuscitation with a degree of maintenance or supplementation of albumin.

Expert commentary: The potential clinical benefits of the use of albumin in selected critically ill patients such as sepsis seem related to its immunomodulatory and anti-inflammatory effects, antioxidant properties, antibiotic transportation and endothelial stabilization. Additional studies are warranted to further elucidate the underlying physiologic and molecular rationale.  相似文献   

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