Molecular and serological prevalence of Coxiella burnetii in bovine dairy herds in southern Chile: A PCR and ELISA-based assessment of bulk tank milk samples

Coxiella burnetii (C. burnetii) is a highly resilient zoonotic bacterium responsible for Q fever, a disease which occurs worldwide, with the exception of New Zealand. However, in Chile, the prevalence and impact of C. burnetii in cattle herds remain poorly understood due to limited research. This study aimed to assess the presence of C. burnetii in dairy cattle herds in southern Chile, using two diagnostic methods on bulk tank milk samples. The results of the study revealed a high prevalence of C. burnetii infection in the analyzed herds. Of the 271 milk tank samples tested, 76% (208/271, CI: 71.1-81.5) tested positive using ELISA, while 73% (200/271, CI: 68.0-78.8) tested positive using qPCR. These findings indicate a significant presence of C. burnetii in the cattle herds studied. Despite the high prevalence observed, no new Q fever outbreaks have been reported in the study area. This discrepancy highlights the need for further research to better understand the transmission dynamics, environmental factors, and livestock management practices associated with C. burnetii infection. These studies will contribute to the development of effective prevention and control strategies and promote public health regarding Q fever.

First test-day postcalving risk factors for clinical mastitis in southern Chile dairy farms: A retrospective cohort study

We conducted a retrospective cohort study to evaluate risk factors associated with clinical mastitis in dairy cows in southern Chile between the first milk test after calving to 200 d in milk (DIM). Data from 8,772 cows were collected from June 2017 to November 2019 on 10 dairy farms selected by convenience in southern Chile. Data were analyzed using a multivariable mixed logistic regression using a manual backward selection process with logit link function and farm as a random effect. The dependent variable was clinical mastitis between the first milking sample collected by monthly milk sampling program up to 200 DIM. Days in milk, fat, urea, parity, season, and somatic cell counts were statistically associated with clinical mastitis in the first 200 d in milk. Cows with higher than average milk yield, parity, urea, and somatic cell count were at greater odds of being diagnosed with clinical mastitis compared with their respective referents. In contrast, higher milk fat was associated with lower odds of clinical mastitis. Significant interactions between days in milk with season and parity were observed, where for every 5-d increase in DIM, the odds of clinical mastitis decreased by different proportions depending on the interaction. Identified risk factors for clinical mastitis using first monthly milk sampling data can help dairy farmers in Chile implement herd-level mastitis prevention and control measures.

L’impact psychosocial de la pandémie de COVID-19 sur les personnes LGBT au Chili

Introduction

Méthode

Résultats

Discussion

Psychosocial impact of COVID-19 pandemic on LGBT people in Chile

Introduction

COVID-19 pandemic has led many countries around the world, including Chile, to take various measures, including physical and, social isolation. The effects of these measures, necessary to prevent the virus from spreading, must be studied. In particular, quarantines are known to have an impact on quality of life and well-being (for example, associated symptoms such as depression, anxiety, post-traumatic stress, and other psychosocial consequences). Furthermore, these effects are expected to be more pronounced in previously disadvantaged populations, such as LGBT people. This paper describes the main measures taken by LGBT population during quarantine to avoid COVID-19 and its psychosocial consequences on an individual and social basis.

Method

Non-probability sampling was used. An online self-administered survey including 1181 participants was used. These were lesbians, gays, bisexuals, and transgender residents over 18 years old from Chile.

Results

Almost eight out of ten participants were in a total quarantine situation. From them, 18.2% were in partial isolation and only 4.6% were not in quarantine. COVID-19 has affected almost all the LGBT participants to a certain extent. COVID-19 has emotionally affected the vast majority of the LGBT participants to a certain extent. In other words, the pandemic has affected their lives. This psychosocial impact of COVID has been greater for people who define themselves as *sexual (include queer, asexual, pansexual, demisexual).

Discussion

The measures taken to prevent the virus transmission significantly affect LGBT people's life. In particular, these measures affect *sexual people. *sexual people must manage discrimination and misunderstanding of their identity in many contexts including their family.

In vitro inactivation of Mycobacterium avium subsp. paratuberculosis (MAP) by use of copper ions

Background

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis, a contagious infectious disease that affects domestic and wild ruminants causing chronic inflammation of the intestine. MAP has proven to be very resistant to both physical and chemical processes, making it difficult to control this pathogen. Based on the recognized antimicrobial properties of copper, the objective of this study was to evaluate the effectiveness of copper ions to reduce MAP numbers and/or MAP viability in a fluid matrix. Besides, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli were used as controls of the effectiveness of copper ions. MAP-spiked PBS was subjected to copper ions treatment at 24 V for 5 min and the PBS suspensions were sampled before and after treatment. MAP viability and quantification were determined using three complementary techniques: a phage amplification assay, MGIT culture and qPCR.

Results

Moderate numbers (10³ CFU ml⁻¹) of the two control bacteria were completely eliminated by treatment with copper ions. For MAP, copper ions treatment reduced both the viability and numbers of this pathogen. Phage assay information quickly showed that copper ions (24 V for 5 min) resulted in a significant reduction in viable MAP. MGIT culture results over time showed statistically significant differences in time-to-detection (TTD) values between PRE and POST treatment. MAP genome equivalent estimates for PBS suspensions indicated that MAP numbers were lower in samples POST-treatment with copper ions than PRE-treatment.

Conclusions

The use of copper ions resulted in a significant reduction of MAP in a liquid matrix, although some MAP survival on some occasions was observed.

The Armc10/SVH gene: genome context, regulation of mitochondrial dynamics and protection against Aβ-induced mitochondrial fragmentation

Mitochondrial function and dynamics are essential for neurotransmission, neural function and neuronal viability. Recently, we showed that the eutherian-specific Armcx gene cluster (Armcx1-6 genes), located in the X chromosome, encodes for a new family of proteins that localise to mitochondria, regulating mitochondrial trafficking. The Armcx gene cluster evolved by retrotransposition of the Armc10 gene mRNA, which is present in all vertebrates and is considered to be the ancestor gene. Here we investigate the genomic organisation, mitochondrial functions and putative neuroprotective role of the Armc10 ancestor gene. The genomic context of the Armc10 locus shows considerable syntenic conservation among vertebrates, and sequence comparisons and CHIP-data suggest the presence of at least three conserved enhancers. We also show that the Armc10 protein localises to mitochondria and that it is highly expressed in the brain. Furthermore, we show that Armc10 levels regulate mitochondrial trafficking in neurons, but not mitochondrial aggregation, by controlling the number of moving mitochondria. We further demonstrate that the Armc10 protein interacts with the KIF5/Miro1-2/Trak2 trafficking complex. Finally, we show that overexpression of Armc10 in neurons prevents Aβ-induced mitochondrial fission and neuronal death. Our data suggest both conserved and differential roles of the Armc10/Armcx gene family in regulating mitochondrial dynamics in neurons, and underscore a protective effect of the Armc10 gene against Aβ-induced toxicity. Overall, our findings support a further degree of regulation of mitochondrial dynamics in the brain of more evolved mammals.

GSK-3β overexpression causes reversible alterations on postsynaptic densities and dendritic morphology of hippocampal granule neurons in vivo

Adult hippocampal neurogenesis (AHN) is crucial for the maintenance of hippocampal function. Several neurodegenerative diseases such as Alzheimer's disease (AD) are accompanied by memory deficits that could be related to alterations in AHN. Here, we took advantage of a conditional mouse model to study the involvement of glycogen synthase kinase-3β (GSK-3β) overexpression (OE) in AHN. By injecting GFP- and PSD95-GFP-expressing retroviruses, we have determined that hippocampal GSK-3β-OE causes dramatic alterations in both dendritic tree morphology and post-synaptic densities in newborn neurons. Alterations in previously damaged neurons were reverted by switching off the transgenic system and also by using a physiological approach (environmental enrichment) to increase hippocampal plasticity. Furthermore, comparative morphometric analysis of granule neurons from patients with AD and from GSK-3β overexpressing mice revealed shared morphological alterations. Taken together, these data indicate that GSK-3β is crucial for hippocampal function, thereby supporting this kinase as a relevant target for the treatment of AD.

The influence of risk factors on the severity of anti-tuberculosis drug-induced hepatotoxicity

BACKGROUND

Hepatotoxicity is one of the most serious adverse effects of anti-tuberculosis drugs (ATD). Although many risk factors have been associated with ATD-induced hepatotoxicity, their influence on hepatitis severity has not been studied systematically.

OBJECTIVES

To evaluate whether the presence of hepatotoxicity risk factors (advanced age, chronic liver disease, abuse of alcohol or other drugs or malnutrition) influences the severity of ATD-induced hepatotoxicity.

DESIGN

A prospective cohort study of 471 active tuberculosis patients treated with isoniazid, rifampicin and pyrazinamide and followed in a tuberculosis clinic between January 1998 and July 2002. Incidence of hepatotoxicity and its severity according to the presence or absence of ATD-induced hepatitis risk factors was evaluated.

RESULTS

The incidence of ATD-induced hepatotoxicity (serum transaminase > 3 x the upper limit of normal [ULN]) was 18.2% (42/231 patients) in the risk factor group and 5.8% (14/240 patients) in the non-risk factor group (OR 3.5; 95% CI 1.9-6.7; P < 0.001). Severe hepatotoxicity (transaminase > 10 x ULN) occurred in 6.9% (16/231) of the risk factor group and in 0.4% (1/240) (OR 17.7; 95% CI 2.3-135; P < 0.001) of the group without risk factors.

CONCLUSIONS

ATD-induced hepatitis is significantly more frequent and more severe in patients with hepatotoxicity risk factors.

Alendronate and etidronate do not regulate interleukin 6 and 11 synthesis in normal human osteoblasts in culture

Bisphosphonates exert a potent inhibitory effect on bone resorption. Several studies have been performed, with contradictory results, to ascertain whether the effect of bisphosphonates on osteoclasts could be produced, at least in part, by modulation of the synthesis of resorption-promoting factors by osteoblasts. The aim of this study was to evaluate the effect of etidronate (10-4-10-9 M) and alendronate (10-7-10-12 M) on the production of IL-6 and IL-11 using human osteoblast cultures. Cytokines were quantified by ELISA, and mRNA expression was tested. Treatment with alendronate and etidronate had no effect on the synthesis of IL-6 or IL-11, and IL-6 and IL-11 mRNA levels. These results were obtained both in nonstimulated cultures and in cultures stimulated by means of TNF-a, IL-1b, and TNF-a+IL-1b, with or without FCS. In conclusion, a possible indirect osteoclast-mediated effect of alendronate and etidronate on bone resorption would not be exerted through reduction in osteoblastic synthesis of IL-6 and IL-11.

Differential distribution of sialic acid in alpha2,3 and alpha2,6 linkages in the apical membrane of cultured epithelial cells and tissues

We used lectin cytochemistry and confocal microscopy to examine the distribution of sialic acid in epithelial cells. Maackia amurensis lectin and Sambuccus nigra agglutinin were used to detect alpha2,3 and alpha2,6 sialic acid, respectively. In Caco-2, HT-29 5M12, and MCF-7 cells, which express sialic acid mainly in one type of linkage, the majority of the signal was observed in the apical membrane. In cells that bound both lectins, alpha2,3 sialic acid was distributed apically, whereas alpha2,6 sialic acid showed a broader distribution. In IMIM-PC-1 cultures, alpha2,3 sialic acid was detected mainly in the apical membrane, whereas alpha2,6 sialic acid was more abundant in the basolateral domain of polarized cells. In these cells, treatment with GalNAc-O-benzyl led to reduced alpha2,3 levels and to an increase and redistribution of alpha2,6 to the apical domain. Similarly, sialic acid was predominantly expressed apically in all epithelial tissues examined. In conclusion, (a) sialic acid is mainly distributed to the apical membrane of epithelial cells, (b) there is a hierarchy in the distribution of sialic acids in polarized epithelial cells, i.e., alpha2,3 is preferred to alpha2,6 in the apical membrane, and (c) IMIM-PC-1 cells are a good model in which to study the regulation of the levels and distribution of sialic acids.

GalNAc-alpha -O-benzyl inhibits sialylation of de Novo synthesized apical but not basolateral sialoglycoproteins and blocks lysosomal enzyme processing in a post-trans-Golgi network compartment

Glycosylation plays an important role in glycoprotein traffic. Our previous work has shown that long term treatment of mucus-secreting HT-29 cells with GalNAc-alpha-O-benzyl reversibly inhibits sialylation and causes the accumulation of apical glycoproteins in cytoplasmic vesicles. We have analyzed at the biochemical level the effects of GalNAc-alpha-O-benzyl on glycoprotein processing. Both apical and basolateral membrane glycoproteins were sialylated, but GalNAc-alpha-O-benzyl selectively inhibited the sialylation of apical glycoproteins. In addition, lysosomal alpha-glucosidase, which is partially targeted to the apical membrane, was abnormally processed leading to the accumulation of an immature molecular species. Several findings support the conclusion that accumulation of this protein occurs in a post-trans-Golgi network (TGN) compartment: 1) it is partially sialylated; 2) it does not occur when glycoprotein exit from the TGN is blocked at 20 degrees C; 3) upon Triton X-114 partition, it distributes to the aqueous phase, a characteristic that is acquired in a post-TGN compartment; and 4) its appearance is inhibited when cells are cultured in the presence of NH(4)Cl. The processing of cathepsin D was also found to be affected by GalNAc-alpha-O-benzyl treatment. In conclusion, GalNAc-alpha-O-benzyl selectively inhibits sialylation of apical glycoproteins and perturbs lysosomal enzyme processing; these effects occur in a post-TGN acidic compartment and are reminiscent of the alterations found in sialic acid storage diseases.

In vitro analysis of the role of DCC in mucus-secreting intestinal differentiation

The deleted in colorectal cancer (DCC) gene was initially described as a colon cancer-associated tumor suppressor gene and subsequently proposed to be involved in goblet cell differentiation, but its precise role in normal intestine physiology and in cancer remains to be established. We have analyzed DCC mRNA expression in a panel of human colorectal cancer cell lines with a variety of differentiation phenotypes by reverse transcription-polymerase chain reaction (RT-PCR) and have shown that (1) most cell lines showed lower levels of DCC mRNA than normal colonic tissue; (2) only 1 cell line lacked detectable levels of DCC mRNA expression; (3) a discrepancy was found between the detectability of RT-PCR products corresponding to the extracellular and intracellular domains of DCC; and (4) there was no association between the presence of DCC transcripts and the differentiation phenotype. Specifically, DCC was not exclusively associated with the mucus-secreting phenotype, as determined by Alcian blue staining and Northern blotting with mucin gene probes. This was further supported by immunohistochemical results on DCC product and mucins in normal colon: DCC was detected in both goblet and absorptive cells. The introduction of full-length DCC cDNA in undifferentiated HT-29 cells did not have any effect on their differentiation phenotype, as shown by morphological studies and analysis of markers for this process in colon, such as mucins, dipeptidylpeptidase IV, villin and sucrase-isomaltase. There were no effects on cell proliferation in vitro. Our results indicate that DCC is not selectively involved in the mucosecretory differentiation pathway and that it is neither sufficient nor essential for normal intestinal differentiation.

GalNAc-alpha-O-benzyl inhibits NeuAcalpha2-3 glycosylation and blocks the intracellular transport of apical glycoproteins and mucus in differentiated HT-29 cells

Exposure for 24 h of mucus-secreting HT-29 cells to the sugar analogue GalNAc-alpha-O-benzyl results in inhibition of Galbeta1-3GalNAc:alpha2,3-sialyltransferase, reduced mucin sialylation, and inhibition of their secretion (Huet, G., I. Kim, C. de Bolos, J.M. Loguidice, O. Moreau, B. Hémon, C. Richet, P. Delannoy, F.X. Real., and P. Degand. 1995. J. Cell Sci. 108:1275-1285). To determine the effects of prolonged inhibition of sialylation, differentiated HT-29 populations were grown under permanent exposure to GalNAc-alpha-O-benzyl. This results in not only inhibition of mucus secretion, but also in a dramatic swelling of the cells and the accumulation in intracytoplasmic vesicles of brush border-associated glycoproteins like dipeptidylpeptidase-IV, the mucin-like glycoprotein MUC1, and carcinoembryonic antigen which are no longer expressed at the apical membrane. The block occurs beyond the cis-Golgi as substantiated by endoglycosidase treatment and biosynthesis analysis. In contrast, the polarized expression of the basolateral glycoprotein GP 120 is not modified. Underlying these effects we found that (a) like in mucins, NeuAcalpha2-3Gal-R is expressed in the terminal position of the oligosaccharide species associated with the apical, but not the basolateral glycoproteins of the cells, and (b) treatment with GalNAc-alpha-O-benzyl results in an impairment of their sialylation. These effects are reversible upon removal of the drug. It is suggested that alpha2-3 sialylation is involved in apical targeting of brush border membrane glycoproteins and mucus secretion in HT-29 cells.

Epidemiology of human T-lymphotropic virus type II (HTLV-II) infection in Spain. HTLV Spanish Study Group

The human T-lymphotropic virus type II (HTLV-II) has recently been associated with the genesis of some subacute neurological syndromes and, rarely, with atypical T-lymphoid malignancies. The virus is endemic in some Amerindian and African tribes, and among intravenous drug users (IDUs) in North America and Europe. Given that HTLV-II is transmitted by the same routes as other human retroviruses, the screening of antibodies to HTLV-II in blood donors has became a matter of controversy in some countries. Herein, we describe the clinical, epidemiological and virological features of 113 individuals with HTLV-II infection identified in Spain up to September 1995. Most of them (94/113; 83%) were male, and all but seven were natives. Four were African immigrants living in Madrid and 3 had been born in other European countries. All but six subjects were IDUs, and sexual transmission of HTLV-II and transfusion were involved in five and one individual, respectively. Eighty-four percent of the IDUs infected with HTLV-II were co-infected by HIV-I (93/107). Clinical manifestations potentially linked to HTLV-II were absent, although an IDU male co-infected by HIV-1 and HTLV-II developed a severe non-inflammatory proximal myopathy. In conclusion, HTLV-II infection is present in Spain, mainly among IDUs, with a growing incidence and a current overall prevalence of 2.0 percent.

[Adoption: a systemic point of view]

From a systemic viewpoint, communication and structure of adoptive families are analyzed. An isomorphism between the environment interaction with the adoptive family, and the different family subsystems was found out. Within such a conceptualization, the psychological vulnerability of adoptive children is studied.

[Evaluation of various criteria for the interpretation of western blot for the diagnosis of human immunodeficiency virus infection. Spanish Group for the Study of HIV-2]

BACKGROUND

The Western blot (WB) is the most commonly used test to confirm the presence of antibodies against the human immunodeficiency virus type 1 (HIV-1). Different criteria of interpretation of the band profile have been proposed with there being no unanimity as to its reliability. The sensitivity and specificity of several criteria proposed for the interpretation of WB were evaluated and the individual significance of the reactivity of each band of the WB was analyzed.

METHODS

The presence of antibodies against HIV-1 was prospectively studied in 8,073 samples of subjects with risk of infection. A total of 1,993 (25%) were reactive by ELISA and 1,261 were analyzed by WB, with a semiquantitative reading of the bands with a point scale from 0 to 2 being performed. The final interpretation of the WB (negative, doubtful, or positive) was carried out following 5 recommendations of usage. A test designed with synthetic peptides (Pepti-lav) was used as a reference and in discordant cases, other more specific serologic tests and/or genetic analysis by polymerase chain reaction (PCR) were performed.

RESULTS

In order of frequency, the greater sensitivity was found to be for the CRSS (Consortium for Retrovirus Serology Standardization) criteria (97.9%), OMS (96.6%), CDC (Center for Disease Control) (95.9%), ARC (American Red Cross) (95.6%) and FDA (99.8%). The greatest specificity was for the criteria of the OMS, and FDA (99.8%). In order of frequency, the most frequent bands in HIV-1 + individuals were gp160 (99%), gp120, p24, p31, p55, p68, gp41, and p17 (68%). In non infected individuals, the recognized bands were, in decreasing order, p24, p17, p55, p68, p31, and glucoproteins.

CONCLUSIONS

Different criteria of interpretation of the Western blot provide different degrees of sensitivity and specificity. The Western blot is a non standardized, expensive, laborious technique of subjective interpretation which provides an appreciable number of undetermined results.

[A multicenter study of infection with human immunodeficiency virus type-2 (HIV-2) in Spain (1991). The Spanish Group for the Study of HIV-2]

BACKGROUND

To January 1991 thirteen cases of HIV-2 infection had been reported in Spain. Paradoxically, neighboring countries, i.e. France and Portugal, have reported more than one thousand cases, and are the most HIV-2 prevalent areas outside West Africa. We report the results of a prospective, nationwide study on the prevalence of HIV-2 infection conducted in Spain in 1991. In addition, an evaluation of testing methodologies is made.

METHODS

Sera collected from 8,073 individuals at high-risk for HIV infection were screened by a combined HIV-1 plus HIV-2 ELISA. Reactive samples were further evaluated by three tests, as HIV-1 Western blot (WB), HIV-2 specific WB, and a synthetic peptide assay immuno-dot (Pepti-lav, Pasteur).

RESULTS

Fifteen (0.18%) individuals met criteria of HIV-2 infection in both specific WB and SPA. Four (27%) of them showed reactivity to both HIV-1 and HIV-2, and the dual infection was confirmed by polymerase chain reaction (PCR) in 2 out of 3 available samples. The SPA showed higher sensitivity and specificity than WB in the diagnosis and distinction of HIV-1 and HIV-2 infections.

CONCLUSIONS

To January 1992, 28 cases of HIV-2 infection have been described in Spain. All but two were African immigrants. The first cases of HIV-1 plus HIV-2 coinfection have been identified. In HIV high-risk populations, SPA may provide an excellent alternative to WB to confirm ELISA reactive samples.