The role of gut-brain axis in a rotenone-induced rat model of Parkinson's disease

Parkinson's disease (PD) is a widespread neurodegenerative condition affecting millions globally. This investigation centered on the gut-brain axis in a rotenone-induced PD rat model. Researchers monitored behavioral shifts, histological modifications, neurodegeneration, and inflammation markers throughout the rats' bodies. Results revealed that rotenone-treated rats displayed reduced exploration (p = 0.004) and motor coordination (p < 0.001), accompanied by decreased Nissl staining and increased alpha-synuclein immunoreactivity in the striatum (p = 0.009). Additionally, these rats exhibited weight loss (T3, mean = 291.9 ± 23.67; T19, mean = 317.5 ± 17.53; p < 0.05) and substantial intestinal histological alterations, such as shortened villi, crypt architecture loss, and inflammation. In various regions, researchers noted elevated immunoreactivity to ionized binding adapter molecule (IBA)-1 (p < 0.05) and reduced immunoreactivity to glial fibrillary acidic protein (p < 0.05) and S100B (p < 0.001), indicating altered glial cell activity. Overall, these findings imply that PD is influenced by gut-brain axis changes and may originate in the intestine, impacting bidirectional gut-brain communication.

Gut-microbiome-brain axis: the crosstalk between the vagus nerve, alpha-synuclein and the brain in Parkinson's disease

This critical review of the literature shows that there is a close link between the microbiome, the gut, and the brain in Parkinson's disease. The vagus nerve, the main component of the parasympathetic nervous system, is involved in the regulation of immune response, digestion, heart rate, and control of mood. It can detect microbiota metabolites through its afferents, transferring this gut information to the central nervous system. Preclinical and clinical studies have shown the important role played by the gut microbiome and gut-related factors in disease development and progression, as well as treatment responses. These findings suggest that the gut microbiome may be a valuable target for new therapeutic strategies for Parkinson's disease. More studies are needed to better understand the underlying biology and how this axis can be modulated for the patient's benefit.

The impact of child poverty on brain development: does money matter?

The development of the human nervous system makes up a series of fundamental and interdependent events involving birth, growth, and neuronal maturation, in addition to the positive or negative selection of synapses of these neurons that will participate in the composition of neural circuits essential to the activity of the nervous system. In this context, where environment and social relationships seem to be relevant markers for neurodevelopment, advanced neuroimaging techniques and behavioral assessment tools have demonstrated alterations in brain regions and cognitive functions among children developing in low or high socioeconomic status environments. Considering the aspects mentioned, this review aimed to identify the importance of socioeconomic status in children's brain development, seeking to identify what are the impacts of these factors on the morphological and physiological formation of the nervous system, allowing a greater understanding of the importance of environmental factors in neurodevelopmental processes.

Tumefactive demyelination after covid-19 successfully treated with betainterferon 1A

The Marburg variant of MS is a rare variant that leads to a severe clinical course, with a high rate of mortality or severe residual deficits and unclear pathophysiology. A 20-year-old female patient, presented at the hospital emergency with left inferior limb paresis and visual blurring. The neurologic exam showed complete and proportionate left hemiparesis with pyramidal signs and clonus, loss of proprioception and vibration in lower limbs, tactile, and painful hypoesthesia on the left side. This report describes a rare case of Marburg variant associated with COVID-19 infection.

Dementia and cognitive impairment in adults as sequels of HSV-1-related encephalitis: a review

Considering the variety of mechanisms of Herpes simplex virus (HSV-1) contamination and its broad invasive potential of the nervous system, a life-long latent infection is established. Infected adult individuals may be susceptible to viral reactivation when under the influence of multiple stressors, especially regarding immunocompromised patients. This guides a series of neuroinflammatory events on the cerebral cortex, culminating, rarely, in encephalitis and cytotoxic / vasogenic brain edema. A sum of studies of such processes provides an explanation, even though not yet completely clarified, on how the clinical evolution to cognitive impairment and dementia might be enabled. In addition, it is of extreme importance to recognize the current dementia and cognitive deficit worldwide panorama. The aim of this literature review is to elucidate the available data upon the pathophysiology of HSV-1 infection as well as to describe the clinical panorama of the referred afflictions.

Assessment of vitamin D and inflammatory markers profile in cardiac tissue on Parkinson disease animal model

BACKGROUND

Cardiovascular dysfunctions are common non-motor symptoms in patients with Parkinson's disease (PD) that can result in reduced quality of life and even death. Research in animal models designed to characterize the pathological association between PD and cardiovascular abnormalities is still in its infancy. This study assessed the early impact of the nigrostriatal dopaminergic damage on cardiological features in the unilateral 6-OHDA rat model of PD.

METHODS

Male Wistar rats received unilateral intrastriatal injections of 6-OHDA and sham rats were injected with saline. Animals were studied 15 days later. Immunohistochemistry was used for visualization of tyrosine hydroxylase (TH)-positive neurons in the nigrostriatal system. Electrocardiogram recordings of heart rate were performed in conscious rats. Heart levels of vitamin D, inflammatory cytokines and C-reactive protein were assessed through electrochemiluminescence immunoassay, quantitative reverse transcription PCR and turbidimetric method, respectively.

RESULTS

We found a post-injury reduction of TH-immunoreactivity of approximately 45% in the substantia nigra pars compacta and 20% in the striatum. Heart rate reduction was found in 6-OHDA-lesioned rats as compared with sham counterparts. Reduced levels of vitamin D and increased levels of inflammatory factors (C-reactive protein, IL-6, TNF-α and TGF-β) were detected in the heart tissue of PD rats in comparison with sham.

CONCLUSION

Our findings suggest a link between cardiac tissue changes and cardiac functional changes early after the central dopaminergic damage induced by 6-OHDA. Knowledge of the cardiac abnormalities in the 6-OHDA model is critical in identifying future therapeutic targets and disease-modifying approaches for PD non-motor features.

Effects of Bifidobacterium animalis subsp. lactis HN019 on ligature-induced periodontitis in rats with experimental rheumatoid arthritis

The purpose of this study was to evaluate the effects of systemic administration of the probiotic Bifidobacterium animalis subsp. lactis HN019 (HN019) on ligature-induced periodontitis in rats with experimental rheumatoid arthritis (RA). 28 rats were divided into four groups (n=7): RA (rheumatoid arthritis), RA/PROB (probiotic), RA/EP (experimental periodontitis) and RA/EP/PROB. From day zero, HN019 was added daily to the water of the PROB groups animals until the end of the experiment. From day seven, RA was induced. On day 28, in EP groups, ligatures were positioned around mandibular first molars and remained in position for 11 days, in order to induce periodontitis. The animals were euthanised on day 39. Microtomographic, histomorphometric, immunoenzymatic and microbiological analyses were performed. Data were statistically analysed (P<0.05). Group RA/EP/PROB presented reduced alveolar bone loss, tumour necrosis factor-α and interleukin (IL)-6 levels and increased IL-17 levels when compared with group RA/EP. There were no significant differences regarding connective tissue attachment level and IL-10 levels between groups RA/EP and RA/EP/PROB. Group RA/PROB showed decreased anti-citrullinated protein antibodies levels when compared with groups RA and RA/EP. Group RA/EP/PROB presented a higher rate of aerobic/anaerobic bacteria than group RA/EP. Systemic administration of HN019 promoted a protective effect against periodontal tissue destruction, decreasing both bone loss and inflammatory mediators and increasing the proportion of bacteria compatible with periodontal health, in rats with experimental RA and EP.

Natural infection by Culex flavivirus in Culex quinquefasciatus mosquitoes captured in Cuiabá, Mato Grosso Mid-Western Brazil

New species of insect-specific viruses (ISV) have been reported worldwide. In the present study, the complete genome of Culex flavivirus (CxFV) and partial sequences of other ISVs in Culex quinquefasciatus Say 1823 females (n = 3425) sampled in 200 urban areas census tracts of Cuiaba, state of Mato Grosso, were identified via reverse transcriptase-polymerase chain reaction for a NS5 region of flaviviruses, nucleotide and high-throughput sequencing, and viral isolation in C6/36 cells. CxFV was detected in 16 of 403 mosquito pools; sequences found in the study presented a high similarity with isolates from São Paulo, Brazil and other countries in Latin American that belong to genotype II, supporting the geographical influence on CxFV evolution. The monthly maximum likelihood estimation for CxFV ranged from 1.81 to 9.94 per 1000 mosquitoes. In addition to the CxFV complete genome, one pool contained an ORF1 sequence (756 bp) that belongs to a novel Negevirus from the Sandewavirus supergroup most similar to the Santana virus (77.1%) and another pool presented an RNA-dependent RNA polymerase sequence (1081 bp) of a novel Rhabdovirus most similar to Wuhan mosquito virus 9 (44%). After three passages in C6/36 cells, only CxFV was isolated from these co-infected pools. The importance of ISVs relies on their possible ability to interfere with arbovirus replication in competent vectors.

Exposure to aluminum, aluminum + manganese and acid pH triggers different antioxidant responses in gills and liver of Astyanax altiparanae (Teleostei: Characiformes: Characidae) males

Exposure to aluminum (Al) and aluminum + manganese (Mn) can trigger an increase in reactive oxygen species (ROS) and modify the activity of oxidative defense enzymes. This study investigated whether exposure to Al and Al + Mn at acid pH for 24 and 96 h causes oxidative stress evidenced by antioxidants and oxidative damage in the gills and liver of sexually mature Astyanax altiparanae males. The fish were subsequently immersed in metal-free water for 24 and 96 h to see whether they recovered from the effects of these metals. Exposure to an acid pH boosted the activity of gill superoxide dismutase (SOD) at 96 h and the fish did not recover when immersed for the same period in water at neutral pH. Exposure to Al increased glutathione (GSH) levels (24 h) in the gills, returning to control levels during the recovery period, showing the efficiency of the antioxidant system in preventing lipid peroxidation of the gills and liver. Mn did not modify the activity of the enzymes studied, but did trigger late hepatic lipid peroxidation during the recovery period. The group exposed to Al + Mn exhibited several alterations, including increased concentration of GSH, as well as higher GPx and GR activity in the gills. Despite the defensive responses triggered by acute exposure, during the recovery period there were alterations in catalase (96 h) and an increase in hepatic metallothionein (24 h), but this did not prevent hepatic lipid peroxidation. Al and Al + Mn produced different effects, and the timing of enzymatic and non-enzymatic antioxidant defenses also differed.

Semitendinosus and patellar tendons shear modulus evaluation by supersonic shearwave imaging elastography

PURPOSE

Shear modulus (μ) is directly correlated to the tissue stiffness and can predict the tendon ultimate force to failure. With the knee extended 0° (K0), semitendinosus tendon (ST) is tensioned while patellar tendon (PT) is relaxed. At 80o , knee flexion (K80) tendons present an opposite stress pattern; however, the relation between ST and PT μ in both situations was not studied yet.

METHOD

We accessed the μ of the ST and PT at 0o and 80o knee flexion by supersonic shear wave imaging (SSI) elastography from 18 healthy males. Relative μ indexes were calculated for relaxed and tensioned conditions.

RESULT

The average μ for ST was μST-K0  = 197·62 ± 31·93 kPa and μST-K80  = 77·76 ± 30·08. For TP, values were μTP-K0  = 23·45 ± 5·89 and μTP-K80  = 113·92 ± 57·23 kPa. Relative μ indexes were calculated for relaxed (IR = μST-K80 /μTP-K0 ) and tensioned conditions (IT = μST-K0 /μPT-K80 ). The relative μ indexes were IR = 3·63 ± 1·50 and IT = 2·00 ± 0·96 (P<0·05).

CONCLUSION

Semitendinosus tendon μ was significantly higher than PT μ in both tensioned and relaxed positions. This can predict a higher ultimate force to failure and a less elastic behaviour in ST grafts when compared to PT grafts. This new parameter could aid physicians in graft choice previous to anterior cruciate ligament reconstruction.

The effects of copper on Na(+)/K (+)-ATPase and aquaporin expression in two euryhaline invertebrates

We used immunocytochemical and fluorometric techniques to show that gill cells of two marine invertebrates, the crab Neohelice granulata (osmoregulator) and the clam Mesodesma mactroides (osmoconformer), increase the expression of membrane transporters [Na(+)/K(+)-ATPase and aquaporin (AQP1)] after whole-animals exposure (96 h) to sublethal concentrations of copper in water of salinity 30 ppt, when both clams and crabs are isosmotic with respect to the environmental medium. A plausible interpretation of our findings is that this increased expression in membrane transporters may serve as an attempt to ameliorate the deleterious effects of copper on the mechanisms involved in ion and volume regulation in gill cells.

Systemic lupus erythematosus: association with KIR and SLC11A1 polymorphisms, ethnic predisposition and influence in clinical manifestations at onset revealed by ancestry genetic markers in an urban Brazilian population

Systemic lupus erythematosus (SLE) is an autoimmune disorder of the connective tissue with a wide and heterogeneous spectrum of manifestations, with renal and neurological involvement usually related to worse prognosis. SLE more frequently affects females of reproductive age, and a high prevalence and renal manifestation seem to be associated with non-European ethnicity. The present study aims to investigate candidate loci to SLE predisposition and evaluate the influence of ethnic ancestry in the disease risk and clinical phenotypic heterogeneity of lupus at onset. Samples represented by 111 patients and 345 controls, originated from the city of Belém, located in the Northern Region of Brazil, were investigated for polymorphisms in HLA-G, HLA-C, SLC11A1, MTHFR, CASP8 and 15 KIR genes, in addition to 89 Amerindian samples genotyped for SLC11A1. We also investigated 48 insertion/deletion ancestry markers to characterize individual African, European and Amerindian ancestry proportions in the samples. Predisposition to SLE was associated with GTGT deletion at the SLC11A1 3'UTR, presence of KIR2DS2 +/KIR2DS5 +/KIR3DS1 + profile, increased number of stimulatory KIR genes, and European and Amerindian ancestries. The ancestry analysis ruled out ethnic differences between controls and patients as the source of the observed associations. Moreover, the African ancestry was associated with renal manifestations.

Estimation procedures affect the center of pressure frequency analysis

Even though frequency analysis of body sway is widely applied in clinical studies, the lack of standardized procedures concerning power spectrum estimation may provide unreliable descriptors. Stabilometric tests were applied to 35 subjects (20-51 years, 54-95 kg, 1.6-1.9 m) and the power spectral density function was estimated for the anterior-posterior center of pressure time series. The median frequency was compared between power spectra estimated according to signal partitioning, sampling rate, test duration, and detrending methods. The median frequency reliability for different test durations was assessed using the intraclass correlation coefficient. When increasing number of segments, shortening test duration or applying linear detrending, the median frequency values increased significantly up to 137%. Even the shortest test duration provided reliable estimates as observed with the intraclass coefficient (0.74-0.89 confidence interval for a single 20-s test). Clinical assessment of balance may benefit from a standardized protocol for center of pressure spectral analysis that provides an adequate relationship between resolution and variance. An algorithm to estimate center of pressure power density spectrum is also proposed.

Heterologous amplification of microsatellite loci from mouse and rat in oryzomyine and Thomasomyine South American rodents

Eleven heterologous primers were investigated in 119 individuals of 11 species of rodents of the Oryzomyine and Thomasomyine groups. The animals were collected at four sites of the "Cerrado," a dryland biome located on the Brazilian Plateau, all of them being karyotyped and taxonomically allocated according to the karyotype. Four of these primers, R47, R65, R75 (from Rattus), and ATP (from Mus) cross-amplified in at least one of these taxa, giving products of seven, nine, one, and three bands, respectively. These values are of the same order as others obtained when heterologous primers were amplified in other orders of mammals. Of the 20 products amplified in these two rodent groups by these four primers, only 7 of the bands were seen in a heteromorphic state (one individual presenting two bands), in two species (Rhipidomys aff. leucodactylus and Oryzomys megacephalus). The others occurred as monomorphic bands.

The karyotype of the South American rodent Kunsia tomentosus (Lichtenstein, 1830)

Chromosomal analysis of Kunsia tomentosus showed a karyotype with 2n = 44, constituted by 21 pairs of acrocentric autosomes. The X chromosome was a median acrocentric, between pairs 3 and 4 in size, and the Y chromosome was a small acrocentric (between pairs 19 and 20). Five pairs with nucleolus organizer regions were located at the short arms. C-banding showed blocks of constitutive heterochromatin occurring in the centromeres of all autosomes and of the X chromosome. The Y chromosome was entirely heterochromatic. In order to identify possible homologies, karyotypes of Kunsia and Scapteromys, the phyletically related taxa, were compared. No autosome shared by either genus was found by G-band comparisons. The C-band patterns and those produced by Alu I, Mbo I, Rsa I and Hae III restriction endonucleases were also different. The results of FISH indicated a different composition of the telomeric regions of the chromosomes of both taxa, since in Scapteromys the probes hybridized in both telomeres, and in Kunsia this hybridization only occurred in one of the telomeres. These differences also occurred in the localization and number of nucleolus organizer regions.

Calculation of area of stabilometric signals using principal component analysis

In stabilometry, the sway of the human body in an upright posture is studied by monitoring the displacement of its centre of pressure in the lateral (x) and anterio-posterior (y) directions. The area covered by this trace has been defined as that of an ellipse fitted to the data. Conventionally, its angle of inclination is found through linear regression (LR) on the data in the x-y plane. In the present paper, principal component analysis (PCA) is proposed as providing a more suitable basis for the estimation of angle and area. Results of simulations and stabilometric tests confirm large differences between area and angle estimates obtained by regression of x over y, and y over x, with PCA generally agreeing with either one or the other of the LRs. The PCA technique is therefore recommended as an improved basis for measuring area and inclination of stabilograms, or similar data sets.

[Peripheral neuropathy possibly caused by amiodarone therapy]

A 67 years-old man under amiodarone treatment for thirteen months due to a cardiac arrhythmia developed a mixed sensory-motor neuropathy. Proper diagnosis and withdrawal of the offending drug prompted marked improvement within months of his neurological dysfunction.

An X1X1X2X2/X1X2Y mechanism of sex determination in a South American rodent, Deltamys kempi (Rodentia, Cricetidae)

Chromosome studies on 14 specimens of Deltamys kempi disclosed six males with 2n = 37, NF = 38, six females with 2n = 38, NF = 38, and two females with 2n = 37, NF = 38. G- and C-band analyses revealed a Y-autosome translocation in the males leading to a multiple chromosome system of sex determination of the type X1X1X2X2/X1X2Y, this being the second case of such a mechanism described in rodents. At meiosis the males presented a trivalent in which C-banding studies showed an alternate orientation of the sex chromosomes due to end-to-end association of the X1 and Y chromosomes, the Y and the X2 being held together by interstitial chiasmata. At metaphase II both n = 17 + Y and n = 18 + X1 are regularly observed. The two females with 2n = 37, NF = 38, are heterozygous for an autosomal centric fusion involving chromosomes 1 and 13. The product of the Y-autosome translocation constitutes the largest element of the karyotype (9.4% of the haploid set); the X1 chromosome amounts to 7.8% of this set, including a large heterochromatic block. When only its euchromatic region is considered, this percentage decreases to 4.6%. From two to seven NORs were observed at the telomeres, with a mean of 4.4 +/- 1.1 per cell.

Unusual C-band patterns in three karyotypically rearranged forms of Scapteromys (Rodentia, Cricetidae) from Brazil

Chromosome studies of 30 specimens of the rodent Scapteromys collected at nine localities in southern Brazil revealed the occurrence of three karyotypic taxa with 2n = 36 (one locality), 34 (two localities), and 24 (six localities), although all three had 40 autosomal arms (AN). The G-band analysis indicated that this reduction in diploid number was mainly due to Robertsonian translocations which have occurred along a gradient, possibly in two independent evolutive routes. The C-bands occur on one autosomal pair and on the X and Y in the 2n = 36 and 34 forms and on the X and Y chromosomes only in the 2n = 24 taxon. The broad genomic reorganization which has occurred in this genus, in which the chromosomes do not have large amounts of constitutive heterochromatin, argues against the idea that a large amount of constitutive heterochromatin favors chromosome evolution and speciation.

Fiberoptic endoscopy in the diagnosis of retained gastric antrum

Recurrent peptic ulcer following surgery has been extensively studied, but its causes are not always clear. Difficulties in the differential diagnosis of the various possible factors can be very puzzling, since most of the methods described fail to provide a reliable definitive diagnosis. In the present study the authors report on the results obtained with the use of fiberoptic endoscopy complemented by biopsy of the mucosa of the duodenal stump for the diagnosis of retained gastric antrum in recurrent ulcer following B-II type gastrectomy. Considering the good results obtained with this method in 20 out of 23 patients, with a high degree of accuracy in association with biopsy and without any complications, it is strongly recommended whenever there is a possibility that retained antrum is the cause of recurrent peptic ulcer.

5-Hydroxytryptamine and narcotic-analgesics interactions in the intestine

The effects of 5-hydroxytriptamine (5-HT), 5-HT blocking agents, morphine, narcotic-antagonists and ganglionic blocking agents were tested in the dog intestine by close intra-arterial injection. Morphine, as 5-HT, induced an immediate increase in the intestinal tonus followed by phasic contractions. When 5-HT was injected immediately after cessation of morphine induced phasic contractions, a significant potentiation of the 5-HT induced intestinal contraction could be observed. The potentiation could be demonstrated for other narcotic-analgesics like dextromoramide and it is specific for 5-HT. 5-HT blocking agents like LSD, BOL, and cyproheptadine did not block either 5-HT or morphine. However, bufotenidine, a neural tryptaminergic blocking agent, blocked the effects of both 5-HT and morphine. The effects of 5-HT and morphine upon intestinal motility were also diminished by ganglionic depolarizing agents such as nicotine and DMPP. This effect could, however, be prevented by the pretreatment with hexamethonium. These results seem to confirm the hypothesis of a 5-HT mediator role in the intestinal contractile effect induced by the narcotic-analgesics. On the other hand, narcotic-antagonists such as nalorphine and cyclazocine, not only lacked the 5-HT potentiation effect but also prevented the 5-HT potentiation induced by morphine. Cyclazocine also showed a long lasting 5-HT blocking effect. These results seem to show that the 5-HT potentiating effect of morphine in vivo is very specific and characteristic of the narcotics and thus could be implicated in some of their central effects.