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1.
Proc Biol Sci ; 291(2021): 20232658, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38628130

ABSTRACT

North American salamanders are threatened by intercontinental spread of chytridiomycosis, a deadly disease caused by the fungal pathogen Batrachochytrium salamandrivorans (Bsal). To predict potential dispersal of Bsal spores to salamander habitats, we evaluated the capacity of soil microbial communities to resist invasion. We determined the degree of habitat invasibility using soils from five locations throughout the Great Smoky Mountains National Park, a region with a high abundance of susceptible hosts. Our experimental design consisted of replicate soil microcosms exposed to different propagule pressures of the non-native pathogen, Bsal, and an introduced but endemic pathogen, B. dendrobatidis (Bd). To compare growth and competitive interactions, we used quantitative PCR, live/dead cell viability assays, and full-length 16S rRNA sequencing. We found that soil microcosms with intact bacterial communities inhibited both Bsal and Bd growth, but inhibitory capacity diminished with increased propagule pressure. Bsal showed greater persistence than Bd. Linear discriminant analysis (LDA) identified the family Burkolderiaceae as increasing in relative abundance with the decline of both pathogens. Although our findings provide evidence of environmental filtering in soils, such barriers weakened in response to pathogen type and propagule pressure, showing that habitats vary their invasibility based on properties of their local microbial communities.


Subject(s)
Chytridiomycota , Ecosystem , Animals , RNA, Ribosomal, 16S , Chytridiomycota/physiology , Amphibians/microbiology , Urodela , Soil , North America
2.
Microbiology (Reading) ; 169(10)2023 10.
Article in English | MEDLINE | ID: mdl-37815535

ABSTRACT

Microbiomes are major determinants of host growth, development and survival. In amphibians, host-associated bacteria in the skin can inhibit pathogen infection, but many processes can influence the structure and composition of the community. Here we quantified the shifts in skin-associated bacteria across developmental stages in the striped newt (Notophthalmus perstriatus), a threatened salamander species with a complex life history and vulnerable to infection by the amphibian chytrid fungus Batrachochytrium dendrobatidis and ranavirus. Our analyses show that pre-metamorphic larval and paedomorphic stages share similar bacterial compositions, and that the changes in the microbiome coincided with physiological restructuring during metamorphosis. Newts undergoing metamorphosis exhibited microbiome compositions that were intermediate between paedomorphic and post-metamorphic stages, further supporting the idea that metamorphosis is a major driver of host-associated microbes in amphibians. We did not find support for infection-related disruption of the microbiome, though infection replicates were small for each respective life stage.


Subject(s)
Microbiota , Urodela , Animals , Urodela/microbiology , Amphibians/microbiology , Metamorphosis, Biological , Skin/microbiology , Bacteria/genetics , Endangered Species
3.
Viruses ; 14(12)2022 12 06.
Article in English | MEDLINE | ID: mdl-36560729

ABSTRACT

Burmese python (Python bivittatus) is an invasive snake that has significantly affected ecosystems in southern Florida, United States. Aside from direct predation and competition, invasive species can also introduce nonnative pathogens that can adversely affect native species. The subfamily Serpentovirinae (order Nidovirales) is composed of positive-sense RNA viruses primarily found in reptiles. Some serpentoviruses, such as shingleback nidovirus, are associated with mortalities in wild populations, while others, including ball python nidovirus and green tree python nidovirus can be a major cause of disease and mortality in captive animals. To determine if serpentoviruses were present in invasive Burmese pythons in southern Florida, oral swabs were collected from both free-ranging and long-term captive snakes. Swabs were screened for the presence of serpentovirus by reverse transcription PCR and sequenced. A total serpentovirus prevalence of 27.8% was detected in 318 python samples. Of the initial swabs from 172 free-ranging pythons, 42 (24.4%) were positive for multiple divergent viral sequences comprising four clades across the sampling range. Both sex and snout-vent length were statistically significant factors in virus prevalence, with larger male snakes having the highest prevalence. Sampling location was statistically significant in circulating virus sequence. Mild clinical signs and lesions consistent with serpentovirus infection were observed in a subset of sampled pythons. Testing of native snakes (n = 219, 18 species) in part of the python range found no evidence of python virus spillover; however, five individual native snakes (2.3%) representing three species were PCR positive for unique, divergent serpentoviruses. Calculated pairwise uncorrected distance analysis indicated the newly discovered virus sequences likely represent three novel genera in the subfamily Serpentovirinae. This study is the first to characterize serpentovirus in wild free-ranging pythons or in any free-ranging North America reptile. Though the risk these viruses pose to the invasive and native species is unknown, the potential for spillover to native herpetofauna warrants further investigation.


Subject(s)
Boidae , Nidovirales , Animals , Florida/epidemiology , Ecosystem , Introduced Species
4.
Ecohealth ; 19(1): 8-14, 2022 03.
Article in English | MEDLINE | ID: mdl-35000043

ABSTRACT

A persistent 2-month long outbreak of Ranavirus in a natural community of amphibians contributed to a mass die-off of gopher frog tadpoles (Lithobates capito) and severe disease in striped newts (Notophthalmus perstriatus) in Florida. Ongoing mortality in L. capito and disease signs in N. perstriatus continued for 5 weeks after the first observation. Hemorrhagic disease and necrosis were diagnosed from pathological examination of L. capito tadpoles. We confirmed detection of a frog virus 3 (FV3)-like Ranavirus via quantitative PCR in all species. Our findings highlight the susceptibility of these species to Rv and the need for long-term disease surveillance during epizootics.


Subject(s)
DNA Virus Infections , Disease Outbreaks , Ranavirus , Ranidae , Salamandridae , Animals , DNA Virus Infections/mortality , DNA Virus Infections/veterinary , Disease Outbreaks/veterinary , Florida/epidemiology , Larva/virology , Morbidity , Ranidae/virology , Salamandridae/virology
5.
J Synchrotron Radiat ; 28(Pt 1): 78-85, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33399555

ABSTRACT

Recent Mössbauer experiments in a rotating system reported by others in the literature have involved the application of synchrotron radiation onto a spinning semi-circular resonant absorber. Here, the physical interpretation of these methodologies, and their alleged performance improvement, is analyzed in the light of our own team's past experience based instead on the traditional laboratory setup. It is shown that a number of fundamental shortcomings in the approach reported in the literature deprives it of any practical significance with respect to the improvement of the technique of Mössbauer rotor experiments with a synchrotron source. It is concluded that, at present, only Mössbauer experiments relying on an ordinary compact source of resonant radiation and a resonant absorber both fixed on the rotor promise to provide crucial information with respect to the physical origin of the observed energy shift between emitted and absorbed resonant radiation in a rotating system.

6.
J Synchrotron Radiat ; 25(Pt 6): 1703-1710, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-30407180

ABSTRACT

A comparative analysis of Mössbauer experiments in a rotating system between a recent application using synchrotron radiation [Friedman et al. (2016). Eur. Phys. Lett. 114, 50010; Friedman et al. (2017). J. Synchrotron Rad. 24, 661-666] and usual sources of resonant radiation is carried out. The principal methodological difference between these experiments can be related to the fact that in the former set of experiments the source of the resonant radiation rests in a laboratory frame whereas for the latter set of experiments the source is attached to a rotating system. It is concluded that the utilization of ordinary Mössbauer sources remains the most promising path for further research appertaining to the Mössbauer effect in rotating systems.

7.
Sci Rep ; 8(1): 11937, 2018 Aug 09.
Article in English | MEDLINE | ID: mdl-30093690

ABSTRACT

We analyze the quantum phase effects for point-like charges and electric (magnetic) dipoles under a natural assumption that the observed phase for a dipole represents the sum of corresponding phases for charges composing this dipole. This way we disclose two novel quantum phases for charged particles, which we named as complementary electric Aharonov-Bohm (A-B) phase and complementary magnetic A-B phase, respectively. We reveal that these phases are derived from the Schrödinger equation only in the case, where the operator of momentum is re-defined via the replacement of the canonical momentum of particle by the sum of its mechanical momentum and interactional field momentum for a system of charged particles. The related alteration should be introduced to Klein-Gordon and Dirac equations, too, and implications of this modification are discussed.

8.
Ir J Med Sci ; 185(3): 673-676, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26193980

ABSTRACT

PURPOSE: Fine-needle aspiration biopsy (FNAB) of the thyroid is generally a well-tolerated procedure associated with weak levels of pain. However, pain may be very intense in some patients. The cause for the pain in these patients has not been identified. The hypothesis of this study is that there is a likely relationship between pain level and nodule depth during FNAB. MATERIALS AND METHODS: Included in the study were 98 patients with euthyroid nodular goiter who underwent FNAB. When ultrasound guided thyroid fine-needle aspiration biopsy was performed findings such as the distance of the nodule to the skin, the size of the nodule, visual analogue scale (VAS) score values were recorded. FINDINGS: The distance of nodule to skin and nodule size was measured, respectively, as 10.7 ± 2.8 mm and 21.7 ± 8.6 mm. Mean VAS score was 36 ± 16. FNAB-related pain was correlated with the nodule depth (r = 0.43, p < 0.001). In the logistic regression analysis, we also found that high VAS score class was effected by only nodule depth (B = -1.619; OR 1.287; CI 1.057-1.565, p < 0.05). CONCLUSION: Our results show that pain increased significantly during FNAB in patients who had more deeply situated nodules. Local anesthetic methods may be recommended for these patients.


Subject(s)
Biopsy, Fine-Needle/methods , Pain/diagnosis , Thyroid Nodule/surgery , Female , Humans , Male , Middle Aged , Thyroid Nodule/pathology
9.
Turk Neurosurg ; 24(5): 774-7, 2014.
Article in English | MEDLINE | ID: mdl-25269053

ABSTRACT

Vascular complications after lumbar discectomy are rarely seen. We present a unique and potentially life-threatening postoperative complication from this procedure. A 27-year-old man was admitted to our emergency vascular unit 1 day after a lumbar discectomy, during which a scalpel blade fragmented and a part was lost. Radiological images of the patient were performed and a broken scalpel blade was located anterior to the sacrum. An anterior laparotomy was performed which identified a mass within the left iliac vein that migrated suddenly to the inferior vena cava. An emergency angiography was performed, by which time the scalpel blade had ascended to the right-sided inferior pulmonary artery. It was subsequently removed via a right lateral thoracotomy.


Subject(s)
Diskectomy/adverse effects , Foreign Bodies/diagnosis , Lumbar Vertebrae , Postoperative Complications/diagnosis , Surgical Instruments , Vena Cava, Inferior/diagnostic imaging , Adult , Angiography , Foreign Bodies/diagnostic imaging , Foreign Bodies/etiology , Humans , Male , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology
10.
Phys Rev Lett ; 112(9): 091302, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24655238

ABSTRACT

The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the search range 0.64 eV ≲ ma ≲ 1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of gaγ ≲ 3.3 × 10(-10) GeV(-1) at 95% C.L., with the exact value depending on the pressure setting. Future direct solar axion searches will focus on increasing the sensitivity to smaller values of gaγ, for example by the currently discussed next generation helioscope International AXion Observatory.

11.
Case Rep Surg ; 2013: 209494, 2013.
Article in English | MEDLINE | ID: mdl-24386586

ABSTRACT

Introduction. Diaphragm injuries develop following penetrating or blunt traumas. The purpose of the case report is to present a 28 year old male patient with stable hemodynamic findings treated with laparoscopic approach following a liver injury combined with a right diaphragm injury caused by a sharp penetrating object. Case. 4 cm long transverse laceration was observed near the middle axillary line in the 6th right intercostal space in the examination performed on a 28 year old male patient who applied to the emergency service due to sharp penetrating object injury. Respiratory sounds were decreased in the right side and the examination revealed sensitivity in the abdomen. Elevation in the right diaphragm and hemopneumothorax was monitored in chest X-ray and computerized tomography. Closed subaqueous thorax drain was placed and the patient was taken to the surgery with a right diaphragm injury prediagnosis. Laparoscopic exploration was performed to the patient with stable hemodynamic findings by entering through 10 mm port above the abdomen. 6 cm long injury at the right side of diaphragm and approximately 2 cm deep at the deepest point and 5 cm long linear laceration was observed in the 7th segment of the liver. The diaphragm was repaired laparoscopically with sutures that do not melt on their own. Tampon was applied to the laceration in the liver and bleeding control was performed with suture. Patient was discharged on the 3rd day because he had no problems during postoperative follow-ups. Result. No noticed right side diaphragm rupture and possible concomitant visceral organ injuries following a penetrant injury that can cause significant mortality and morbidity should be definitely kept in mind. The detection of right side diaphragm and liver injury is vital with high mortality in case of delayed diagnosis, and direct radiography and computerized tomography are helpful in the diagnosis. Surgical treatment with laparoscopic approach is a method that leads to less hospitalization duration and less pain in cases that are hemodynamically stable.

12.
Phys Rev Lett ; 107(26): 261302, 2011 Dec 23.
Article in English | MEDLINE | ID: mdl-22243149

ABSTRACT

The CERN Axion Solar Telescope (CAST) has extended its search for solar axions by using (3)He as a buffer gas. At T=1.8 K this allows for larger pressure settings and hence sensitivity to higher axion masses than our previous measurements with (4)He. With about 1 h of data taking at each of 252 different pressure settings we have scanned the axion mass range 0.39 eV≲m(a)≲0.64 eV. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of g(aγ)≲2.3×10(-10) GeV(-1) at 95% C.L., the exact value depending on the pressure setting. Kim-Shifman-Vainshtein-Zakharov axions are excluded at the upper end of our mass range, the first time ever for any solar axion search. In the future we will extend our search to m(a)≲1.15 eV, comfortably overlapping with cosmological hot dark matter bounds.

13.
Surg Radiol Anat ; 25(2): 120-6, 2003 May.
Article in English | MEDLINE | ID: mdl-12748815

ABSTRACT

Pedicle screw fixation of the spine has become one of the most stable and versatile methods of spine fixation, and knowledge of pedicle morphology is crucial for the safe application of these systems. We undertook this study because only a few reports have investigated Eastern populations. Lumbar pedicle anatomy, i.e., pedicle width (PW) and pedicle height (PH), transverse and sagittal pedicle angles (TPA, SPA), and pedicle length (PL), were assessed in the following two groups: (1) computed tomography scans of 29 normal adults, and (2) 16 dried lumbar spines obtained from the Anatomy Department. Interpedicular distance was different in each group. PW ranged from 4 mm to 14 mm. In both groups, the narrowest PH was 8.2 mm, the widest 19.7 mm. TPA ranged from 6(o) to 19(o) and increased from L1 to L5. In the sagittal plane, the pedicles angled caudally at L5. PL was longest at L1 and shortest at L5. In conclusion, pedicle dimensions and angles may show individual and structural differences. Our data were not significantly different from previous reported data. A detailed knowledge of these relationships is important for any surgery involving screw purchase via a pedicle, to prevent screw cutout and failure of fixation or neurological injury. Selection of the proper diameter of screw is an important issue for safe placement. Knowledge of the pedicle axis length is essential in choosing screw lengths but should always be checked intraoperatively with fluoroscopic control during screw insertion.


Subject(s)
Lumbar Vertebrae/anatomy & histology , Racial Groups , Adolescent , Adult , Body Weights and Measures , Bone Screws/adverse effects , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Male , Radiography
14.
Neurol India ; 50(3): 256-61, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12391448

ABSTRACT

Ninety white hybrid rabbits, each weighing 2.5 to 3.5 kg, were used for this experimental model. Thirty rabbits were used for control, and sixty other rabbits were investigated for the response of host to the dural graft. In all animals, a dural defect, 1 x 1 cm in size, was created on the left parietal area following craniotomy. In the control group the excised free dural piece was then sutured again to the area from which it had been excised before. The dural defect was closed with dehydrated human dura mater (DHD) in the half of the rabbits in the group of study, and with autogenous fascia lata (AFL) in the other half. After operation, animals in each group were then subjected to one of five different groups comprising of 3,14,30,60 and 90 days follow-up periods. At the end of follow-up periods, histological, parameters such as cellular inflammatory response, development of fibrous tissue, capsulation, and calcification were examined in specimens obtained from the animals. There was no significant difference between AFL and DHD grafts. In conclusion, it seems that DHD is suitable as an ideal dural graft, because the immune response of host to DHD was almost similar to AFL.


Subject(s)
Dura Mater/surgery , Dura Mater/transplantation , Graft Survival/immunology , Animals , Desiccation , Humans , Models, Animal , Rabbits , Transplantation, Heterologous
15.
Phys Rev A ; 54(1): 52-56, 1996 Jul.
Article in English | MEDLINE | ID: mdl-9913457
16.
Phys Rev D Part Fields ; 49(10): 5604-5606, 1994 May 15.
Article in English | MEDLINE | ID: mdl-10016881
17.
Phys Rev Lett ; 62(1): 5-7, 1989 Jan 02.
Article in English | MEDLINE | ID: mdl-10039534
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