Vector competence of Mexican and Honduran mosquitoes (Diptera: Culicidae) for enzootic (IE) and epizootic (IC) strains of Venezuelan equine encephalomyelitis virus

Experimental studies evaluated the vector competence of Ochlerotatus taeniorhynchus (Wiedemann), Culex cancer Theobald, Culex pseudes (Dyar and Knab), Culex taeniopus Dyar and Knab, and a Culex (Culex) species, probably Culex quinquefasciatus Say, and Culex nigripalpus Theobald from Chiapas, Mexico, and Tocoa, Honduras, for epizootic (IC) and enzootic (IE) strains of Venezuelan equine encephalomyelitis (VEE) virus. Culex pseudes was highly susceptible to infection with both the IC and IE strains of VEE (infection rates >78%). Patterns of susceptibility to VEE were similar for Oc. taeniorhynchus collected in Mexico and Honduras. Although Oc. taeniorhynchus was highly susceptible to the epizootic IC strains (infection rates > or = 95%, n = 190), this species was less susceptible to the enzootic IE strain (infection rates < or = 35%, n = 233). The Culex (Culex) species were refractory to both subtypes of VEE, and none of 166 contained evidence of a disseminated infection. Virus-exposed Cx. pseudes that refed on susceptible hamsters readily transmitted virus, confirming that this species was an efficient vector of VEE. Although Oc. taeniorhynchus that fed on hamsters infected with the epizootic IC strain transmitted VEE efficiently, only one of six of those with a disseminated infection with the enzootic IE virus that fed on hamsters transmitted virus by bite. These data indicate that Cx. pseudes is an efficient laboratory vector of both epizootic and enzootic strains of VEE and that Oc. taeniorhynchus could be an important vector of epizootic subtypes of VEE.     

Increased matrix metalloproteinase-9 with elastolysis in nocturnal asthma.

BACKGROUND: Matrix metalloproteinase-9 (MMP-9) is capable of degrading elastin, whereas tissue inhibitor of metalloproteinase-1 (TIMP-1) can inhibit MMP-9 activity. We observed reduced airway tissue elastin volume density in six subjects with nocturnal asthma (NA) as compared with seven subjects with nonnocturnal asthma (NNA) and seven normal controls (NL) when endobronchial biopsies were evaluated morphometrically at 4:00 PM and 4:00 AM. OBJECTIVE: We hypothesized that increased metalloproteinases and decreased tissue inhibitors of metalloproteinases in the airways of subjects with NA may be responsible for reduced elastin volume density. METHODS: Ten additional subjects with NA, 10 subjects with NNA, and 7 normal control subjects underwent bronchoscopy with bronchoalveolar lavage at 4:00 PM and 4:00 AM. Levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were determined in bronchoalveolar lavage by enzyme-linked immunosorbent assay. RESULTS: There was a fourfold circadian increase in bronchoalveolar lavage levels of MMP-9, and there was a twofold increase in MMP-9:TIMP-1 ratio in NA subjects from 4:00 PM to 4:00 AM. There were no circadian changes in the NNA and NL subjects. At 4:00 AM, MMP-9 levels and the MMP-9:TIMP-1 ratio were highest in NA subjects. At 4:00 PM, no significant group differences were observed. The MMP-9 levels positively correlated with the overnight fall in forced expiratory volume in 1 second and the MMP-9/TIMP-1 ratio negatively correlated with the 4:00 AM % predicted forced expiratory volume in 1 second. CONCLUSIONS: Our results from these two pilot studies suggest that increased MMP-9 and decreased TIMP-1 at night in NA may lead to reduced elastin density.     

A rapid hemi-nested PCR for HTLV-I detection.

A hemi-nested PCR approach was adopted to detect HTLV-1 infection in clinical samples of peripheral blood mononuclear cells (PBMCs) from subjects with positive or indeterminate serological results. Our results showed that the hemi-nested PCR quickly solved the diagnostic query, detecting the presence of proviral HTLV-1 DNA in two of the 252 patients with inconclusive serological results. The main advantage of this method are the typology of DNA extraction, allowing a consistent DNA recovery without amplification problems, the rapidity (4-5 hours), the performance of the assay and its comparable or better sensitivity than other HTLV-1 PCR formats.     

Domains of macaque DC-SIGN essential for capture and transfer of simian immunodeficiency virus

The C-type lectin DC-SIGN mediates the capture and transfer of simian immunodeficiency virus (SIV) from macaque dendritic cells (DCs) to permissive T-cells. To further identify the determinants in macaque DC-SIGN required for capture and transfer of virus, we created mutants containing deletions or point mutations in the extracellular domains, and tested their ability to capture and transmit SIV. We found that SIV bound to the carbohydrate recognition domain (CRD) of macaque DC-SIGN via the envelope protein. In addition, deleting the C-terminal half of the CRD, or mutating amino acids within this region that contact Ca(2+) or mannose, disrupted virion capture activity. However, an N-terminal CRD deletion mutant was capable of binding SIV, indicating that this region was not necessary for binding. Finally, deletion of the neck domain also reduced the capacity for macaque DC-SIGN to capture SIV. Interestingly, ICAM-3, the cellular ligand for DC-SIGN, did not bind to any of the DC-SIGN mutants, including mutants with amino acid changes in the N-terminal region of the CRD. These data suggest that the binding sites for SIV and ICAM-3 may be distinct but overlapping. Together, the data demonstrate the importance of both the neck and the CRD of macaque DC-SIGN for efficient capture of SIV and binding to ICAM-3.     

Correlation of human decidual and cord blood mononuclear cell cytokine production

Human decidua has been shown to produce a number of cytokines. We hypothesized that decidual cytokine production influences cord blood mononuclear cell (CBMC) cytokine production and that cytokine profiles of decidua from allergic women differ from those of decidua from nonallergic women. Using enzyme-linked immunosorbent assay, we measured unstimulated and concanavalin A/phorbol myristate acetate-stimulated production of interleukin-4 (IL-4), IL-5, IL-10, IL-13 and interferon- gamma (IFN-gamma) by decidual explants from 59 healthy women delivered by unlabored cesarean section and from corresponding CBMCs in 39 of the 59. Except for IL-10, there was little or no unstimulated cytokine production. There was a strong correlation between stimulated decidual and stimulated CBMC IFN-gamma production (p = 0.01). In allergic women the ratio of IL-13 to IL-4 production was increased in stimulated explants (p = 0.03). Stimulated CBMCs from infants of allergic mothers were more likely to produce detectable levels of IL-5 than those from infants of nonallergic mothers (p = 0.04) and had a tendency toward higher IL-13 levels as well (p = 0.07). These results suggest that maternal and fetal IFN-gamma production is closely linked and that maternal allergy appears to influence cytokine production in the neonate for IL-5 and possibly IL-13.     

Endophytic bacteria in Coffea arabica L

Eighty-seven culturable endophytic bacterial isolates in 19 genera were obtained from coffee plants collected in Colombia (n = 67), Hawaii (n = 17), and Mexico (n = 3). Both Gram positive and Gram negative bacteria were isolated, with a greater percentage (68%) being Gram negative. Tissues yielding bacterial endophytes included adult plant leaves, various parts of the berry (e.g., crown, pulp, peduncle and seed), and leaves, stems, and roots of seedlings. Some of the bacteria also occurred as epiphytes. The highest number of bacteria among the berry tissues sampled was isolated from the seed, and includes Bacillus , Burkholderia , Clavibacter , Curtobacterium , Escherichia , Micrococcus , Pantoea , Pseudomonas , Serratia , and Stenotrophomonas . This is the first survey of the endophytic bacteria diversity in various coffee tissues, and the first study reporting endophytic bacteria in coffee seeds. The possible role for these bacteria in the biology of the coffee plant remains unknown.     

Changes in neurofilament gene expression occur after axotomy of dorsal root ganglion neurons: Anin situ hybridization study

Neurofilaments (NFs) are predominant elements in large myelinated axons, where they are thought to serve the important function of maintaining axonal caliber. Previous studies have shown that changes in NF synthesis and axonal transport occur after axonal injury in rat dorsal root ganglion (DRG) cells. The resulting reduction in the NF supply to DRG axons is thought to be largely responsible for the observed decrease in axonal diameter in the proximal axonal stump after an injury. In the present study, we test the hypothesis that a change in NF gene expression precedes the changes in synthesis and transport of NF proteins. To address this hypothesis, the levels of mRNA encoding the 68-kilodalton (kd) neurofilament protein (NF68) in adult rat DRG neurons were assessed at different times after peripheral axotomy usingin situ hybridization. For these studies we used a³⁵S-labeled cDNA probe to NF68. The levels of NF68 mRNA in sensory neurons located in ipsilateral fourth and fifth lumbar DRG at 1, 7, and 14 days after sciatic nerve crush were compared to those in normal DRG neurons using quantitative autoradiography. In large DRG neurons (> 1000m²), the levels of NF68 mRNA were significantly reduced relative to normal at 1, 7, and 14 days after axotomy. Medium-sized cells (601–1000m²) exhibited a reduction only at 14 days postinjury, and small-sized cells were not significantly affected. These findings indicate that larger DRG neurons which give rise to large myelinated sensory axons exhibit a change in NF gene expression after axonal injury. The observed changes in NF68 mRNA levels temporally precede changes in NF synthesis and transport in injured DRG cells. Thus, a change in NF gene expression may be an important component of an effective regenerative response and a critical step at which axonal caliber is regulated in injured neurons.     

Magnesium in Obesity,Metabolic Syndrome,and Type 2 Diabetes

Magnesium (Mg²⁺) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg²⁺ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg²⁺ deficiency, such as the lack of a clear definition of Mg²⁺ nutritional status, the use of different Mg²⁺ salts and dosage and the different duration of the Mg²⁺ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg²⁺, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D.     

Medication-Related Osteonecrosis of the Jaw (MRONJ): Are Antiresorptive Drugs the Main Culprits or Only Accomplices? The Triggering Role of Vitamin D Deficiency

Osteonecrosis of the jaw (ONJ) is a severe clinical condition characterized mostly but not exclusively by an area of exposed bone in the mandible and/or maxilla that typically does not heal over a period of 6–8 weeks. The diagnosis is first of all clinical, but an imaging feedback such as Magnetic Resonance is essential to confirm clinical suspicions. In the last few decades, medication-related osteonecrosis of the jaw (MRONJ) has been widely discussed. From the first case reported in 2003, many case series and reviews have appeared in the scientific literature. Almost all papers concerning this topic conclude that bisphosphonates (BPs) can induce this severe clinical condition, particularly in cancer patients. Nevertheless, the exact mechanism by which amino-BPs would be responsible for ONJ is still debatable. Recent findings suggest a possible alternative explanation for BPs role in this pattern. In the present work we discuss how a condition of osteomalacia and low vitamin D levels might be determinant factors.     

Increased COVID-19 Lockdown Burden in Italian Adults with Gastrointestinal Diseases

Background: Coronavirus disease 2019 (COVID-19) causes not only severe illness but also detrimental effects associated with the lockdown measures. The present study aimed to evaluate reported lifestyle changes in a cohort of adults in Italy, including physical exercise, food choices, and psychological wellbeing, after two months of lockdown. Methods: A web survey on social media (Facebook and LinkedIn) of 32 multiple-choice questions aiming to evaluate the impact of the national COVID-19 lockdown in a sample of Italian adults. Results: We received 1378 complete responses (women 68.3%, mean age 39.5 ± 12.5 years). The percentage of participants reporting regular exercise decreased during lockdown (52 vs. 56.5%). The vast majority of people continued to consume the three traditional meals per day, but the consumption of meat, fish, and eggs significantly decreased. Women reported more frequent anxiety, sadness, fear, and feelings of insecurity than men. The factors predicting the worst outcome during the lockdown were being a woman, low education and income, gastrointestinal diseases. Conclusion: The lockdown has had a limited impact on food choices and physical exercise in Italian adults of our series, since most of them made an effort to improve their lifestyle. However, women with gastrointestinal diseases reported more frequent negative feelings and poor adaptation to the lockdown.