SARS‐CoV‐2 re‐infection versus prolonged shedding: A case series

Since the start of the SARS‐CoV‐2 pandemic, it has been difficult to differentiate between SARS‐CoV‐2 re‐infection and prolonged RNA shedding. In this report, we identified patients with positive RT‐PCR results for SARS‐CoV‐2 ≥70 days apart. Clinical and laboratory data were collected and criteria were applied to discern whether the presentation was consistent with SARS‐CoV‐2 re‐infection or prolonged viral RNA shedding. Eleven individuals met the initial testing criteria, of which, seven met at least one criteria for re‐infection and four were consistent with prolonged RNA shedding. These data demonstrate the need for criteria to differentiate SARS‐CoV‐2 re‐infection from prolonged RNA shedding.     

Technical assessment of WHO-621 periodontal probe made in Brazil

This study technically assessed the WHO-621 periodontal probe made in Brazil as well as its dimensional and weight stability after sterilization. The following characteristics were measured in one hundred (100) new probes: diameter and linear area of tip sphere and beginning and ending references of its colored band by means of indirect computerized morphometric method, and weight, by means of a digital balance within 0.01 mm precision. Fifty (50) probes underwent one hundred (100) cycles of either steam or heat sterilization. The WHO-621 Trinity probe showed mean values of 0.66 mm in its longitudinal and 0.54 mm in its transversal sphere diameters; 0.40 mm2 in its sphere linear area; 3.56 mm and 5.76 mm for the beginning and ending of the colored band, respectively. Its mean weight was 10.12 g with small variation. Some of the measurements showed significant changes after both sterilization procedures. Neither of the sterilization methods showed to be more advantageous (Student's t-test, p = 0.05).     

Alliance predicts patients' outcome beyond in-treatment change in symptoms

The authors examined the relations among therapeutic alliance, outcome, and early-in-treatment symptomatic improvement in a group of 86 patients with generalized anxiety disorders, chronic depression, or avoidant or obsessive-compulsive personality disorder who received supportive-expressive dynamic psychotherapy. Although alliance at Sessions 5 and 10, but not at Session 2, was associated with prior change in depression, alliance at all sessions significantly predicted subsequent change in depression when prior change in depression was partialed out. The results are discussed in terms of the causal role of the alliance in therapeutic outcome.     

Apoptosis induced by gamma irradiation of<Emphasis Type="Italic"> Taenia solium</Emphasis> metacestodes

Gamma irradiation of food is considered a possible approach to control food-borne diseases. In cysticercosis, previous studies have shown that irradiating (with 0.3 kGy) pork infected with Taenia solium larvae completely inhibits growth of the parasite. This study was conducted to evaluate the mechanisms that induce the effect of gamma irradiation on metacestodes of T. solium. Metacestodes were obtained from several infected pigs and irradiated with a dose of 0.3 kGy. The viability of the metacestodes was evaluated by their capacity to evaginate in vitro and in vivo development to tapeworms after they were orally infected into prednisolone-treated golden hamsters. Using the typical ladder pattern of fragmented DNA and the TdT-mediated DUTP-nick-end labeling assay, apoptosis was evaluated in metacestodes after irradiation and in the scolices and tapeworms recovered from infected hamsters at 21 days post-infection. Apoptosis was observed in the structure of scolices obtained from hamsters at 21 days post-infection with irradiated metacestodes, This study provides evidence of the existence of apoptosis in the irradiated metacestodes of T. solium and helps elucidate the possible mechanisms that are involved when gamma irradiation inhibits the normal development of the T. solium metacestode into the adult worm.     

Two epitopes shared by Taenia crassiceps and Taenia solium confer protection against murine T. crassiceps cysticercosis along with a prominent T1 response

Taenia crassiceps recombinant antigens KETc1 and KETc12 have been shown to induce high level of protection against experimental murine T. crassiceps cysticercosis, an experimental model successfully used to test candidate antigens for use in vaccination against porcine Taenia solium cysticercosis. Based on the deduced amino acid sequence, KETc1 and KETc12 were chemically synthesized in linear form. Immunization with KETc1 induced 66.7 to 100% protection against murine cysticercosis, and immunization with KETc12 induced 52.7 to 88.1% protection. The elicited immune response indicated that both peptides contain at least one B-cell epitope (as demonstrated by their ability to induce specific antibodies) and one T-cell epitope that strongly stimulated the proliferation of T cells primed with either the free peptide or total cysticercal T. crassiceps antigens. The high percentage of spleen cells expressing inflammatory cytokines points to the likelihood of a T1 response being involved in protection. The protective capacity of the peptides and their presence in all developmental stages of T. solium point to these two epitopes as strong candidates for inclusion in a polyepitopic synthetic vaccine against T. solium pig cysticercosis.     

Tooth Pulp- and Facial Hair Mechanoreceptor-evoked Responses of Trigeminal Sensory Neurons Are Attenuated during Ketamine Anesthesia

Background: Evidence exists that ketamine, administered systemically using a dose required for inducing a state of anesthesia, may antagonize nociceptive but not innocuous input to lumbar dorsal horn neurons. However, it is unclear whether ketamine exerts this selective action on sensory inputs to trigeminal sensory neurons. The current study was undertaken to compare the responses evoked in trigeminal sensory neurons by electrical stimuli applied to the tooth pulp versus air-puff stimuli applied to facial hair mechanoreceptors (FHMs) during quiet wakefulness versus ketamine anesthesia.

Methods: Accordingly, responses of rostral trigeminal sensory nuclear complex (TSNC) and trigeminothalamic tract neurons evoked by tooth pulp (a source of small-diameter fiber input) and FHMs (a source of larger-diameter fiber input) were recorded extracellularly from chronically instrumented cats before, during, and after recovery from the anesthetic state induced by a single (2.2 mg/kg) intravenous injection of ketamine.

Results: Overall, tooth pulp-evoked responses of TSNC neurons were maximally suppressed by 50% within 5 min after the intravenous administration of ketamine. Ketamine also suppressed the FHM-evoked responses of TSNC and trigeminothalamic neurons by 45%. The time course of ketamine's suppressive action was equivalent for tooth pulp- and FHM-evoked responses. However, the recovery of tooth pulp-evoked TSNC neuronal responses at suprathreshold intensities was markedly prolonged compared with neuronal responses driven by threshold stimuli or FHM.