Acritarcos Anormais: Um Caso Teratológico no Limite Llandovery/Wenlock na Bacia do Amazonas, Brasil

Abnormal acritarchs include forms that present morphological anomalies. They occur in several intervals of the Silurian System, but become particularly abundant around the Llandovery/Wenlock Series boundary. The documentation of abnormal acritarchs is still relatively poor in the palynological literature. The first mention of a possible case of acritarch malformation in Veryhachium europaeum was from the Silurian Maplewood Shale of New York, although not assigned to any chronostratigraphic or paleoecological significance to it. Posteriorly, a study of the Silurian acritarchs from the Visby and Slite Formations of Gotland (Sweden), different hypotheses were considered in order to explain anomalies observed in the processes of some species. It was concluded that variations in water luminosity and temperature could have brought about pathological effects on the Gotland acritarchs. Furthermore, it was suggested that the noticeable occurrence of abnormal acritarchs near the Llandovery/Wenlock boundary could be related to such global phenomena as widespread volcanic activity, paleomagnetic inversions, or the impact of extraterrestrial bolides. In the present work, abnormal acritarchs are recorded for the first time in Llandovery/Wenlock boundary sediments of the Pitinga Formation (Trombetas Group) in the Amazon Basin, northern Brazil, reliably dated by chitinozoans. This new documentation includes some species described from Gotland, like Veryhachium sp., Ammonidium microcladum, and Salopidium granuliferum.Teratological representatives of these taxa share common features, as they all bear unusually thin walls and inflated, deformed processes. Such anomalies in Amazon Basin Silurian acritarchs are interpreted as the effect of stressing environmental conditions on the marine organic-walled microphytoplankton. Possible causes may include changes in seawater temperature and salinity, probably related to the sharp sea-level fluctuations that characterize the Llandovery/Wenlock transition on a global scale.Acritarcos anormais são indivíduos portadores de anomalias morfológicas e que são encontrados em diversos níveis ao longo da série siluriana, mas particularmente abundantes dentro do limite Llandovery/Wenlock. São poucos os trabalhos que fazem referências a acritarcos anormais. Na primeira citação foi descrito um Veryhachium europaeum “hiperatrofiado”, atribuído como uma forma “monstruosa” porém, sem conotação cronoestratigráfica ou paleoecológica. Posteriormente, em estudo sobre os acritarcos silurianos de Gotland, Formação Visby e Slite, Suécia, foram discutidas hipóteses para explicar a origem das anomalias nos processos de certas espécies. Concluiu-se que a variação de luminosidade e temperatura, poderia explicar os efeitos patológicos verificados nos acritarcos de Gotland. Atribuiu-se ainda, que a relação entre a distribuição de acritarcos anormais no limite Llandovery/Wenlock, provém de fenômenos globais como atividades vulcânicas, inversões paleomagnéticas ou queda de material extraterrestre. Neste trabalho são registrados, pela primeira vez, em sedimentos da Formação Pitinga (limite Llandovery/Wenlock), na Bacia do Amazonas algumas espécies descritas em Gotland, entre as quais: Veryhachiun sp., Ammonidium microcladum e Salopidium granuliferum. Essas espécies apresentam como característica comum parede fina e processos inflados e deformados. Considera-se essas anomalias registradas em acritarcos silurianos da Bacia do Amazonas como produtos de fatores ambientais estressantes tais como variação de temperatura e salinidade resultantes das oscilações do nível do mar, próprias neste intervalo de tempo

The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications

Reduced Cancer Incidence in Huntington's Disease: Analysis in the Registry Study

Background: People with Huntington's disease (HD) have been observed to have lower rates of cancers. Objective: To investigate the relationship between age of onset of HD, CAG repeat length, and cancer diagnosis. Methods: Data were obtained from the European Huntington's disease network REGISTRY study for 6540 subjects. Population cancer incidence was ascertained from the GLOBOCAN database to obtain standardised incidence ratios of cancers in the REGISTRY subjects. Results: 173/6528 HD REGISTRY subjects had had a cancer diagnosis. The age-standardised incidence rate of all cancers in the REGISTRY HD population was 0.26 (CI 0.22-0.30). Individual cancers showed a lower age-standardised incidence rate compared with the control population with prostate and colorectal cancers showing the lowest rates. There was no effect of CAG length on the likelihood of cancer, but a cancer diagnosis within the last year was associated with a greatly increased rate of HD onset (Hazard Ratio 18.94, p < 0.001). Conclusions: Cancer is less common than expected in the HD population, confirming previous reports. However, this does not appear to be related to CAG length in HTT. A recent diagnosis of cancer increases the risk of HD onset at any age, likely due to increased investigation following a cancer diagnosis

International Nosocomial Infection Control Consortiu (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care–associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line–associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN

Clinical and genetic characteristics of late-onset Huntington's disease

Background: The frequency of late-onset Huntington's disease (&gt;59 years) is assumed to be low and the clinical course milder. However, previous literature on late-onset disease is scarce and inconclusive. Objective: Our aim is to study clinical characteristics of late-onset compared to common-onset HD patients in a large cohort of HD patients from the Registry database. Methods: Participants with late- and common-onset (30–50 years)were compared for first clinical symptoms, disease progression, CAG repeat size and family history. Participants with a missing CAG repeat size, a repeat size of ≤35 or a UHDRS motor score of ≤5 were excluded. Results: Of 6007 eligible participants, 687 had late-onset (11.4%) and 3216 (53.5%) common-onset HD. Late-onset (n = 577) had significantly more gait and balance problems as first symptom compared to common-onset (n = 2408) (P &lt;.001). Overall motor and cognitive performance (P &lt;.001) were worse, however only disease motor progression was slower (coefficient, −0.58; SE 0.16; P &lt;.001) compared to the common-onset group. Repeat size was significantly lower in the late-onset (n = 40.8; SD 1.6) compared to common-onset (n = 44.4; SD 2.8) (P &lt;.001). Fewer late-onset patients (n = 451) had a positive family history compared to common-onset (n = 2940) (P &lt;.001). Conclusions: Late-onset patients present more frequently with gait and balance problems as first symptom, and disease progression is not milder compared to common-onset HD patients apart from motor progression. The family history is likely to be negative, which might make diagnosing HD more difficult in this population. However, the balance and gait problems might be helpful in diagnosing HD in elderly patients