Trypanosoma sp. infection in Boa constrictor snakes: morphological, hematological, clinical biochemistry, molecular, and phylogenetic characteristics

There are few reports of Trypanosoma in snakes, as well as little information about its pathogenicity in these animals. Thus, the present study aimed to characterize Trypanosoma found in Boa constrictor snakes, to verify the influence of the parasitism on hematological and clinical biochemistry parameters, and to perform a phylogenetic study of the isolates. Blood samples from sixty-one boas were analyzed for the presence of trypanosomatids and by hematological and clinical biochemistry assays. The flagellates that were found in this analysis were used for cell culture, morphometry, and molecular analysis. Later, molecular typing phylogenetic studies were performed. Nine positive animals (14.75%) were identified by microscopy analysis. The hematological results showed that parasitized animals presented significantly lower levels of packed cell volume, hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin. In the leukogram, eosinophils and heterophils counts were higher in parasitized animals. Considering the molecular analyses, the isolates presented a higher identity of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the 18S small subunit ribosomal RNA (SSU rRNA) gene fragments with Trypanosoma serpentis. The phylogenetic tree, using the GAPDH, clustered all isolates with T. serpentis and Trypanosoma cascavelli. This is the first description of T. serpentis parasitizing boas and of the clinical changes caused by trypanosomatid infection in snakes.

Impact of booster vaccination on COVID-19 outcomes in Portuguese population aged 80 or more years old

Background

Vaccination is essential to control SARS-CoV-2 transmission and complications. The study aimed to estimate the number of SARS-CoV-2 infections, COVID-19 hospitalizations and deaths averted by booster vaccination in Portuguese population aged 80 or more years old.

Methods

We developed an ecological study for the period of the Omicron variant of concern predominance (week 2 to week 16, 2022). Data on vaccine coverage and effectiveness, and number of events of different severity reported to the national COVID-19 surveillance system were used to estimate the number of averted events, prevented fraction and number needed to vaccinate. Uncertainty intervals (UI) were obtained using Monte Carlo simulations.

Results

By week 2 2022, vaccination coverage in the target population reached 91.2%. Booster vaccine effectiveness was 4.1% (CI95%: -0.1 to 9.0), 87.5% (CI95%: 84.9 to 89.7) and 83.2 (CI95%: 80.3 to 85.7) against infection, hospitalization and death, respectively. During the study period, 70862 SARS-CoV-2 infections, 2697 COVID-19 hospitalizations and 2106 deaths were reported. Booster vaccination averted 2731 (UI95%: -298 to 5838) infections, 10629 (UI95%: 9173 to 12127) hospitalizations and 6608 (UI95%: 5725 to 7546) COVID-19 related deaths among individuals aged 80 years or more resident in Portugal. Prevented fractions were 3.7% (UI95%: 0 to 7.6%), 79.7% (UI95%: 77.3 to 81.7%) and 75.8% (UI95%: 73.2 to 78.1%), respectively. It would require to vaccinate 59 individuals (UI95%: 52 to 69) to prevent one hospitalization and 94 individuals (UI95%: 82 to 109) to prevent one death in the target population.

Conclusions

The booster vaccination strategy had considerable impact on preventing severe outcomes in the Portuguese population aged 80 and more years old.

Key messages

• High vaccine coverage combined with high vaccine effectiveness resulted in considerable reduction of severe COVID-19 outcomes.

• Information on number of outcomes of different severity levels averted by COVID-19 booster vaccination allows to strength public health communication.

Assessing the use and understanding of the Portuguese heat-health warning system (ÍCARO)

BACKGROUND

Heatwaves can lead to increased mortality. In the Portuguese heat-health warning system (HHWS), ÍCARO, a daily report with heat-related mortality prediction is sent to heat-health action plan (HHAP) practitioners. HHAP practitioners assess risk and implement measures to prevent heatwave-related impact, but ÍCARO's use and understanding are unknown. We assessed ÍCARO's use and understanding by key HHAP practitioners.

METHODS

We conducted semi-structured interviews with national/regional HHAP practitioners. Interviews were recorded, transcribed and analysed using thematic content analysis. To maximize credibility a validation process was implemented through researcher triangulation; a sample of 30 segments was recorded by independent researchers.

RESULTS

We conducted six interviews with nine professionals (mean time 52 min) from five regions. We identified four categories: report's content and presentation, report's reception and communication, ÍCARO and risk assessment and other issues. Practitioners use ÍCARO and perceived it as relevant; they raised issues on its interpretation and felt these were not fully addressed, given researchers' use of statistical/epidemiological terms. We identified the need for improved communication and report's clarity.

CONCLUSIONS

Our study stresses the need for collaboration between experts within HHWS/HHAP. Despite ÍCARO's understanding being challenging, practitioners consider it a relevant tool. Researchers should use less statistical language and clarify ÍCARO's interpretation. Practitioners' needs should be considered when developing/revising tools.

Assessing the use and understanding of the Portuguese Heat–Health Warning System (ÍCARO)

Background

Heatwaves can lead to increased mortality. Portugal has a Heat-Health Warning System (HHWS) in place (ÍCARO system). Researchers at the Instituto Ricardo Jorge send a daily report with heat-related mortality forecasts to key stakeholders (e.g. Heat-Health Action Plans (HHAP) staff). HHAP practitioners issue warnings and implement measures to prevent heatwaves-related mortality. ICARO is amongst the recommended data sources to assess risk and issue warnings but its use and understanding is unknown. Therefore, we aimed to assess ÍCARO’s use and understanding by key HHAP practitioners.

Methods

We conducted semi-structured interviews with national and regional HHAP practitioners. Interviews were recorded, transcribed, and analysed using thematic content analysis. Intercoder reliability was applied to a sample of segments from 5 of 6 interviews.

Results

We conducted 6 interviews with 9 professionals (mean time 52 minutes). We identified 4 categories: Report’s content and presentation, Report’s reception and communication, ÍCARO and risk assessment, Other issues. Practitioners use ÍCARO and perceived it as very relevant tool. However, they mentioned several questions on its interpretation. Practitioners also felt their questions were not fully answered, given researchers’ use of statistical terms. Finally, practitioners referred the need to assess risk at the local level, information not currently provided. We also identified the need for improved communication and report’s clarity.

Conclusions

Our study stresses the need for an integrated collaboration between experts within HHWS and HHAP. Despite ICARO’s understanding being challenging, practitioners consider it a relevant tool. Researchers should use less statistical language and clarify ÍCARO interpretation. Practitioners’ needs should be considered when developing or revising tools. We are currently implementing some of these recommendations in an attempt to close the gap between researchers and practitioners.

Key messages

Portuguese Heat–Health Action Plans practitioners use heat-related mortality forecasts (ICARO) and perceived it as very relevant instrument. However there find ICARO’s interpretation challenging. Portuguese Heat/Health Action Plans Practitioners’ needs should be considered when revising or developing tools, and notes should be added to clarify statistical/technical concepts.

Phylogeny of Neotropical Sicarius sand spiders suggests frequent transitions from deserts to dry forests despite antique, broad-scale niche conservatism

Phylogenetic niche conservatism (PNC) shapes the distribution of organisms by constraining lineages to particular climatic conditions. Conversely, if areas with similar climates are geographically isolated, diversification may also be limited by dispersal. Neotropical xeric habitats provide an ideal system to test the relative roles of climate and geography on diversification, as they occur in disjunct areas with similar biotas. Sicariinae sand spiders are intimately associated with these xeric environments, particularly seasonally dry tropical forests (SDTFs) and subtropical deserts/scrublands in Africa (Hexophthalma) and the Neotropics (Sicarius). We explore the role of PNC, geography and biome shifts in their evolution and timing of diversification. We estimated a time-calibrated, total-evidence phylogeny of Sicariinae, and used published distribution records to estimate climatic niche and biome occupancy. Topologies were used for estimating ancestral niches and biome shifts. We used variation partitioning methods to test the relative importance of climate and spatially autocorrelated factors in explaining the spatial variation in phylogenetic structure of Sicarius across the Neotropics. Neotropical Sicarius are ancient and split from their African sister-group around 90 (57-131) million years ago. Most speciation events took place in the Miocene. Sicariinae records can be separated in two groups corresponding to temperate/dry and tropical/seasonally dry climates. The ancestral climatic niche of Sicariinae are temperate/dry areas, with 2-3 shifts to tropical/seasonally dry areas in Sicarius. Similarly, ancestral biomes occupied by the group are temperate and dry (deserts, Mediterranean scrub, temperate grasslands), with 2-3 shifts to tropical, seasonally dry forests and grasslands. Most of the variation in phylogenetic structure is explained by long-distance dispersal limitation that is independent of the measured climatic conditions. Sicariinae have an ancient association to arid lands, suggesting that PNC prevented them from colonizing mesic habitats. However, niches are labile at a smaller scale, with several shifts from deserts to SDTFs. This suggests that PNC and long-distance dispersal limitation played major roles in confining lineages to isolated areas of SDTF/desert over evolutionary history, although shifts between xeric biomes occurred whenever geographical opportunities were presented.

Morphometry of porcine spermatozoa and its functional significance in relation with the motility parameters in fresh semen

Both the study and the relationship between sperm design and sperm function have been a target of several researchers. In our study we have evaluated the relationship between the morphometry of sperm head and midpiece as well as the relationship between morphometry of these two spermatic components and sperm motion characteristics in the boar. Analysis of regression (lineal and multiple) and principal components analysis were used for the study of these relationships. Semen samples from five Iberian boars were taken for analysis. Analysis of morphometry was assessed by CASMA system and motility by CASA system. Sperm midpiece showed a significant relationship (positive or negative, depending on the morphometric parameter evaluated) with sperm head. VSL, LIN, STR, BCF and VAP showed a significant relationship with several head and midpiece morphometric parameters. Finally, through the analysis of multiple lineal regression we obtained several statistical models that predict STR, LIN, VCL, ALH, BCF, PC1 and PC2 (the last two variables have been obtained from a principal components analysis) as a function of one, two or three morphometric parameters. Our results suggest a co-evolution of sperm head and midpiece and in addition that sperm motion characteristics of porcine spermatozoa are influenced by morphometry of head and midpiece.

Morphometric changes in boar spermatozoa induced by cryopreservation

Computer-assisted sperm morphometry analysis was used to determine the effects of cryopreservation on boar sperm head and midpiece morphometry. Sperm-rich fractions were collected from five mature boars. Three microscope slides were prepared from single extended sperm samples prior freezing and post-thawing. All slides were stained with Hemacolor, and 250 sperm images were obtained from each slide. The sperm head dimensions for length, width, area, perimeter and four shape factors and sperm-midpiece dimensions for area, width, angle and distance were determined in each spermatozoa. The effects of sperm freezing on sperm dimensions within and among boars were determined. A previous discriminant analysis of the results was able to correctly classify a 78.3 and 82% of fresh and frozen-thawed spermatozoa respectively. Sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for length, width, area and perimeter. Sperm midpieces were also significantly smaller in cryopreserved spermatozoa for width and area. The highest changes in morphometric dimensions after the freeze-thawing process were found in the midpiece of spermatozoa. The variability of morphometric measurements only was significantly different between fresh and thawed samples for head rugosity and midpiece area. The effects of cryopreservation on morphometric parameters were similar in the boars, which allow us to conclude that cryopreservation process does not have a different effect in each individual boar. In summary, morphometric changes associated with the cryopreservation process on boar spermatozoa do not apparently depends on an effect at individual level.

MRI of medulloblastoma in adults

Medulloblastoma has variable appearances on MRI in both children and adults. Adults are more likely to have heterogeneous cerebellar hemisphere tumours, and this is thought to be related to the greater prevalence of desmoplastic tumours in adulthood. Few studies have addressed the MRI features of adult medulloblastoma and the specific characteristics of desmoplastic and classic tumours have not been analysed. Our aim was to analyse the imaging characteristics of desmoplastic (DM) and classic (CM) medulloblastomas in adult. We retrospectively studied preoperative MRI of six men and three women, median age 33 years, range 23-53 years, with pathologically proved medulloblastomas. There were six (67%) with DM. The tumour was in the cerebellar hemisphere in eight patients (89%), including the three with CM, one of which was bilateral. All tumours were heterogeneous, giving predominantly low or isointense signal on T1- and isointense signal on T2-weighted images. Cystic or necrotic areas in all patients were particularly visible on T2-weighted images. Contrast enhancement was absent in one DM and varied from slight to intense in eight (three CM), homogeneous in one DM and patchy in seven. All tumours extended to the surface of the cerebellum and two had well-defined margins. MRI does not allow a clear distinction between DM and CM in adults.

[A survey of visceral leishmaniasis in dogs from Santa Maria and neighbouring municipalities, State of Rio Grande do Sul]

Five dogs from the municipalities of Santa Maria, Itaara and Júlio de Castilhos, in the centre of the Brazilian State of Rio Grande do Sul, were diagnosed as positive for visceral leishmaniasis. A survey was developed by indirect immunofluorescence in blood obtained in filter paper from 40 dogs from Santa Maria, 20 from Itaara and 11 from Júlio de Castilhos. Examined dogs were generally related to those reputedly positive. Besides the above dogs, blood from 44 stray dogs from Júlio de Castilhos, 68 from Cachoeira do Sul and 20 from Caçapava do Sul was also examined. Slightly positive sera ( 1:40) were examined with ELISA. PCR and histology was used to examine the liver, spleen, lungs and lymph nodes from a sixth dog considered at necropsy to be positive for visceral leishmaniasis. All results for the 204 dogs were negative. This indicates that visceral leishmaniasis, due to various factors discussed below, is extremely rare in this region. A more detailed exam of the material from the five dogs considered positive is necessary.

[Multiple gliomas. Illustrative cases of 4 different presentations]

Multiple gliomas are uncommon and may be classified according to: a) the time of presentation in early (at diagnosis) or late (during treatment); b) the characteristics of computed tomography or magnetic resonance imaging (CT/MRI) in multifocal (with evidence of spread) and multicentric (without evidence of spread). From 212 patients with histopathologic diagnosis of glioma evaluated from March/90 to September/99, 15 (7%) had multiple lesions. We describe 4 patients: early multicentric, late multicentric, early multifocal and late multifocal, with emphasis on characteristics of CT/MRI and possible differential diagnosis. The differential diagnosis of multiple lesions in the central nervous system includes mainly infectious/inflammatory diseases and metastasis, however multiple gliomas should always be considered, even in patients with known systemic cancer, as described by others. Considering that CT/MRI features are not definite, the diagnosis should always be confirmed by histopathologic examination.

Giant pseudoaneurysm of the extracranial vertebral artery: case report

Pseudoaneurysms of the extracranial vertebral artery are extremely rare due to their deep location and the anatomical protection of this artery. They can be caused by cervical traumas (firearm injuries, sports, hyperextension of the neck and iatrogeny). The authors report the case of a patient who developed a giant pseudoaneurysm of the extracranial vertebral artery after surgery for the removal of a tumor of the cerebellopontine angle in which surgical lesion of the artery occurred. Treatment was performed by endovascular approach. Literature is reviewed and comments are made on the physiopathogeny of the lesion and the different forms of treatment.

[Influence of age on systolic and diastolic time intervals in normal individuals]

OBJECTIVE

To evaluate the influence of age (I) on the left ventricle (VE) systolic time intervals, the S2O interval, the pulse transmission time (TTP) and the relative amplitude of the a wave (Aa%) of the apexcardiogram (ACG) of normal individuals.

METHODS

202 subjects considered as normal by clinical and electrocardiographic examinations were studied. Their age (I) was 38 +/- 13 years (average +/- 1 SD), being 125 male and 77 female. The electrocardiogram (ECG), phonocardiogram, ACG and carotid arterial pulse tracing (PC) were simultaneously recorded. The following intervals were determined: Electromechanical (IEM)--from the onset of QRS complex of the ECG to the ascending branch of the great wave of the ACG (A point); mechanical systole (SM)--from the A point of the ACG to the beginning of first high frequency vibration of the aortic component of the second heart sound (S2); ejection period (FE)--from the beginning of the anacrotic branch of the PC to the nadir of its dicrotic notch (ID); isovolumic contraction time (FIS)--subtracting FE duration to the SM duration; S2O interval--since S2 to the O point (nadir) of the ACG; Aa%--relation percentage expressed between a wave amplitude and total amplitude of the ACG; pulse transmission time--since S2 to ID. Statistically significant correlations (p less than 0.05) between I (years expressed) and the previously mentioned variables were investigated.

RESULTS

It was possible to verify: a) the IEM and FIS intervals were not significantly correlated with I; b) the FE had a linear, positive and significant correlation with I (r = 0.222); c) the correlations between FE and heart rate (FC) were not significantly different between the considered age groups (14-34, 35-49, 50-69 years); d) the S2O interval had a linear, negative and significant correlation with FC (r = -0.196), and a linear, positive and significant correlation with I (r = 0.392); e) multiple regression equation between S2O, I and FC was: S2O = 70 - 0.36 x FC + 0.55 x I; f) the Aa% had a linear, positive and significant correlation with I (r = 0.252); g) TTP has a linear, negative and significant correlation with I (r = -0.793).

CONCLUSIONS

a) The FE increases with I related probably to the afterload increasing that follows aging process; b) the S2O interval increases with I reflecting the elongation of the relaxing time that is associated to the senescence; c) the Aa% increases with I, expressing the reduction of the compliance of the VE associated to the aging; d) the TTP decreases with I related to the increasing of velocity of the pulse wave that follows senescence and is attributed to the increasing of the aortic stiffness.

Steroid profiles during spawning in male common carp

The profiles of testosterone (T) 11-ketotestosterone (11-KT), 17 alpha-hydroxy-4-pregnen-3-one (17-P), and 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P) were determined in groups of spermiating male common carp (Cyprinus carpio) which were or were not mated with females and subjected to an increase in water temperature, a treatment which usually induces females to spawn. The steroid levels were correlated with changes in gonadotropin (GtH). All males mated with ovulatory females showed a GtH surge and spawned. Two distinct classes of these spawned males were differentiated based on their initial androgen levels and hormone profiles. Androgen levels were initially elevated in the "high" males. In these fish there was a very rapid shift in the steroidogenic pathway from androgen to progestogen production coincident with the GtH surge. In the "low" males, 17-P levels rose significantly in response to the GtH surge, but there was no steroidogenic shift. In the males mated with nonovulatory females, the levels of 17-P, 17,20 beta-P, T, and 11-KT all increased coincident with a small rise in GtH; there was no steroidogenic shift. In the unmated males, the steroid profiles were similar to those in the nonspawned fish, except that T and 11-KT levels were significantly lower in comparison. In all groups, 17-P rose higher than 17,20 beta-P, and 11-KT was generally the predominant androgen. A model is proposed which explains the steroidogenic shift in the "high" males. This involves the inhibition of androgen biosynthesis by 17,20 beta-P or by a related progestogen.

Suprasellar germinoma: an unusual clinical presentation

A case is described of suprasellar tumor with diabetes insipidus, diminishing visual acuity, inferior bitemporal quadrantanopia, and hypopituitarism in a 19-year-old man. Computerized tomographic scan of the brain after contrast injection demonstrated periventricular enhancement. Diagnosis of germinoma was made on the basis of clinical and radiographic information and a biopsy that revealed malignant cells. The tumor responded well to radiation therapy. Diagnostic difficulties were created by systemic manifestations unrelated to endocrinopathy. Pertinent literature is reviewed.