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1.
Am J Case Rep ; 25: e942872, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885190

RESUMO

BACKGROUND Bartter syndrome is a rare, inherited salt-wasting tubulopathy caused by mutations in 1 of 6 genes that express ion transport channels in the thick ascending limb of nephrons. Excessive prostaglandin E2 and associated hyperreninemic hyperaldosteronism occurs, causing polyhydramnios, polyuria, prematurity, failure to thrive, and characteristic physical features. Hypokalemia, hypochloremic metabolic alkalosis, and, depending on the affected gene, hypercalciuria and nephrocalcinosis are hallmarks of Bartter syndrome. CASE REPORT A 9-month-old male infant, born prematurely due to polyhydramnios, presented in the Emergency Department with dehydration due to incoercible vomiting and significant polyuria. A 6-year-old male infant with a previous history of prematurity due to polyhydramnios was referred to the Pediatric Endocrinology Department due to short stature and notable polydipsia and polyuria. Considering these marked symptoms, both cases triggered suspicion and started workup for arginine-vasopressin insufficiency/resistance. However, during the investigations, a broader clinical revision revealed that both had dysmorphic physical features (triangularly shaped face, prominent forehead, protruding ears, drooping mouth), poor growth, impaired weight gain, and typical biochemical findings (hypokalemic metabolic alkalosis, hypercalciuria, secondary hyperaldosteronism) of Bartter syndrome. Genetic testing confirmed the diagnosis of Bartter syndrome types 1 and type 2, respectively, and this diagnosis allowed proper treatment and significant clinical improvements, personalized follow-up, and genetic counseling for parents desiring further healthy pregnancies. CONCLUSIONS Here, we present clinical and follow-up findings of 2 patients with Bartter syndrome types 1 and 2 discovered upon a broader clinical revision of suspected arginine-vasopressin insufficiency/resistance. We also review pertinent data on diagnosis and management of this challenging syndrome.


Assuntos
Síndrome de Bartter , Humanos , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/genética , Masculino , Lactente , Criança , Arginina Vasopressina
2.
Int J Parasitol Drugs Drug Resist ; 24: 100525, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359731

RESUMO

Leishmaniasis is a disease caused by Leishmania spp., affecting millions of people around the world. For decades, its treatment has been based on pentavalent antimonials, which notoriously cause toxic side effects in patients. In this study, epoxy-α-lapachone incorporated into an oil-in-water-type microemulsion (ELAP-ME) and meglumine antimoniate (MA) were assayed in monotherapy and in combination (ELAP-ME/MA) in BALB/c mice infected with Leishmania (Leishmania) amazonensis. In general, there was a reduction in paw lesion size (up to 37% reduction) and decreases of parasite loads in the footpad (∼40%) and lymph nodes (∼31%) of animals treated with ELAP-ME/MA, when compared to the non-treated control groups. Analyses of serum biochemical parameters revealed that the ELAP-ME/MA showed lower renal and hepatic toxicity when compared to MA 2-doses/week monotherapy. These findings indicate that the ELAP-ME/MA combination may be a promising approach for the treatment of cutaneous leishmaniasis.


Assuntos
Antiprotozoários , Leishmania , Leishmaniose Cutânea , Naftoquinonas , Compostos Organometálicos , Humanos , Animais , Camundongos , Antimoniato de Meglumina/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Meglumina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Camundongos Endogâmicos BALB C
3.
Front Public Health ; 12: 1326125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371240

RESUMO

Background: Serological surveys for SARS-CoV-2 were used early in the COVID-19 pandemic to assess epidemiological scenarios. In the municipality of Cascais (Portugal), serological testing combined with a comprehensive socio-demographic, clinical and behavioral questionnaire was offered to residents between May 2020 and beginning of 2021. In this study, we analyze the factors associated with adherence to this municipal initiative, as well as the sociodemographic profile and chronic diseases clinical correlates associated to seropositivity. We aim to contribute with relevant information for future pandemic preparedness efforts. Methods: This was a cross-sectional study with non-probabilistic sampling. Citizens residing in Cascais Municipality went voluntarily to blood collection centers to participate in the serological survey. The proportion of participants, stratified by socio-demographic variables, was compared to the census proportions to identify the groups with lower levels of adherence to the survey. Univariate and multivariate logistic regression were used to identify socio-demographic, clinical and behavioral factors associated with seropositivity. Results: From May 2020 to February 2021, 19,608 participants (9.2% of the residents of Cascais) were included in the study. Based on the comparison to census data, groups with lower adherence to this survey were men, the youngest and the oldest age groups, individuals with lower levels of education and unemployed/inactive. Significant predictors of a reactive (positive) serological test were younger age, being employed or a student, and living in larger households. Individuals with chronic diseases generally showed lower seroprevalence. Conclusion: The groups with low adherence to this voluntary study, as well as the socio-economic contexts identified as more at risk of viral transmission, may be targeted in future pandemic situations. We also found that the individuals with chronic diseases, perceiving higher risk of serious illness, adopted protective behaviors that limited infection rates, revealing that health education on preventive measures was effective for these patients.


Assuntos
COVID-19 , Masculino , Humanos , Feminino , COVID-19/epidemiologia , SARS-CoV-2 , Portugal/epidemiologia , Pandemias , Estudos Transversais , Preparação para Pandemia , Estudos Soroepidemiológicos , Doença Crônica
4.
Spine (Phila Pa 1976) ; 49(5): 341-348, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37134139

RESUMO

STUDY DESIGN: This is a cross-sectional survey. OBJECTIVE: The aim was to assess the reliability of a proposed novel classification system for thoracic disc herniations (TDHs). SUMMARY OF BACKGROUND DATA: TDHs are complex entities varying substantially in many factors, including size, location, and calcification. To date, no comprehensive system exists to categorize these lesions. METHODS: Our proposed system classifies 5 types of TDHs using anatomic and clinical characteristics, with subtypes for calcification. Type 0 herniations are small (≤40% of spinal canal) TDHs without significant spinal cord or nerve root effacement; type 1 are small and paracentral; type 2 are small and central; type 3 are giant (>40% of spinal canal) and paracentral; and type 4 are giant and central. Patients with types 1 to 4 TDHs have correlative clinical and radiographic evidence of spinal cord compression. Twenty-one US spine surgeons with substantial TDH experience rated 10 illustrative cases to determine the system's reliability. Interobserver and intraobserver reliability were determined using the Fleiss kappa coefficient. Surgeons were also surveyed to obtain consensus on surgical approaches for the various TDH types. RESULTS: High agreement was found for the classification system, with 80% (range 62% to 95%) overall agreement and high interrater and intrarater reliability (kappa 0.604 [moderate to substantial agreement] and kappa 0.630 [substantial agreement], respectively). All surgeons reported nonoperative management of type 0 TDHs. For type 1 TDHs, most respondents (71%) preferred posterior approaches. For type 2 TDHs, responses were roughly equivalent for anterolateral and posterior options. For types 3 and 4 TDHs, most respondents (72% and 68%, respectively) preferred anterolateral approaches. CONCLUSIONS: This novel classification system can be used to reliably categorize TDHs, standardize description, and potentially guide the selection of surgical approach. Validation of this system with regard to treatment and clinical outcomes represents a line of future study.


Assuntos
Calcinose , Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Reprodutibilidade dos Testes , Estudos Transversais , Vértebras Torácicas/cirurgia , Vértebras Lombares , Variações Dependentes do Observador
5.
World Neurosurg ; 183: 192-203, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37995989

RESUMO

BACKGROUND: Osseous spinal metastases from intracranial meningiomas are rare but represent a serious disease progression. A literature review was performed on this topic to understand the clinical course of patients with this disease entity. We also present a case of spinal metastasis in a patient with a World Health Organization grade III meningioma. METHODS: The PubMed/MEDLINE database was queried on August 15, 2021, using the keywords (meningioma) AND (metastasis) AND (vertebra∗ OR spin∗). All publications reporting outcomes of patients with meningioma metastatic to the spine were included. Disease characteristics, treatment modality, and outcomes were extracted from each study. Because data availability varied widely between studies, no meta-analysis was performed. RESULTS: A total of 30 articles with 33 cases were included. Outcome data varied greatly in terms of quality and length of follow-up. Of 28 cases with reported outcomes data, 20 resulted in patient mortality ranging from a few weeks to 5 years after spinal metastasis. Mean (standard deviation) survival time was 5.8 (6.4) years following initial diagnosis, but only 1.4 (3.2) years from spinal metastasis. The longest survivor was noted to have no recurrence of disease 4 years after spinal metastasis. CONCLUSIONS: Bony spinal metastasis from intracranial meningioma is an extremely rare occurrence. Within the limits of the available literature, outcomes of patients with this disease appear to be poor. However, data reporting is inconsistent, and several articles did not report any outcome data. Further study is needed to better clarify the course and prognosis of this disease.


Assuntos
Neoplasias Meníngeas , Meningioma , Neoplasias da Coluna Vertebral , Humanos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral/patologia , Prognóstico , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia
6.
World Neurosurg ; 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37331476

RESUMO

BACKGROUND: COVID-19 has impacted neurosurgical care around the world. But reports describing patient admission trends during the pandemic have provided limited time frames and diagnoses. The purpose of this paper was to analyze the impact of COVID-19 on neurosurgical care provided to our emergency department during the outbreak. METHODS: Patient admission data were collected based on a list of 35 ICD-10 codes, which were placed into 1 of 4 categories: head and spine trauma ("Trauma"), head and spine infection ("Infection"), degenerative spine ("Degenerative"), and subarachnoid hemorrhage/brain tumor ("Control"). Emergency department (ED) consultations to the Neurosurgery Department were collected from March 2018 to March 2022, representing 2 years before COVID and 2 years of pandemic. We hypothesized that Control cases would remain stable throughout the 2 time periods while Trauma and Infection would decrease. Because of widespread clinic restrictions, we postulated Degenerative (spine) cases presenting to the ED would increase. RESULTS: During the first 2 years of the COVID pandemic, Neurosurgical Trauma and Degenerative ED patients decreased compared with prepandemic levels, while Cranial and Spinal infections increased and continued to do so during the pandemic period studied. Brain tumors and subarachnoid hemorrhages (Control cases) did not change in a significant way throughout the 4-year analysis. CONCLUSIONS: The COVID pandemic significantly altered the demographics of our Neurosurgical ED patient population and continues to do so.

7.
Vaccines (Basel) ; 11(6)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37376405

RESUMO

Degrons are short peptide sequences that signalize target sites for protein degradation by proteases. Herein, we bring forth the discussion on degrons present in proteins related to the immune system of Mus musculus that are potential targets for cysteine and serine proteases of Leishmania spp. and their possible roles on host immune regulation by parasites. The Merops database was used to identify protease substrates and proteases sequence motifs, while MAST/MEME Suite was applied to find degron motifs in murine cytokines (IFN-y, IL-4, IL-5, IL-13, IL-17) and transcription factors (NF-kappaB, STAT-1, AP-1, CREB, and BACH2). STRING tool was used to construct an interaction network for the immune factors and SWISS-MODEL server to generate three-dimensional models of proteins. In silico assays confirm the occurrence of degrons in the selected immune response factors. Further analyses were conducted only in those with resolved three-dimensional structures. The predicted interaction network of degron-containing M. musculus proteins shows the possibility that the specific activity of parasite proteases could interfere with the trend of Th1/Th2 immune responses. Data suggest that degrons may play a role in the immune responses in leishmaniases as targets for parasite proteases activity, directing the degradation of specific immune-related factors.

8.
Spine (Phila Pa 1976) ; 48(14): 1033-1040, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37141463

RESUMO

STUDY DESIGN: In vitro biomechanical study. OBJECTIVE: This study aimed to investigate the biomechanical effects of facet joint violation (FV) on mobility and optically tracked intervertebral disc (IVD) surface strains at the upper level adjacent to L4-5 pedicle screw-rod fixation. SUMMARY OF BACKGROUND DATA: FV is a complication that can occur when placing lumbar pedicle screws; the reported incidence is as high as 50%. However, little is known about how FV affects superior adjacent-level spinal stability, and especially IVD strain, after lumbar fusion. METHODS: Fourteen cadaveric L3-S1 specimens underwent L4-5 pedicle-rod fixation, 7 in the facet joint preservation (FP) group and 7 in the FV group. Specimens were tested multidirectionally under pure moment loading (7.5 Nm). Colored maps of maximum (ε1) and minimum (ε2) principal surface strain changes on the lateral L3-4 disc were generated, with the surface divided into 4 quarters anterior to posterior (Q1, Q2, Q3, and Q4, respectively) for subregional analyses. Range of motion (ROM) and IVD strain were normalized to intact upper adjacent-level and compared between the groups using analysis of variance. Statistical significance was set at P <0.05. RESULTS: Normalized ROM was significantly greater with FV vs. FP in flexion (11% greater; P =0.04), right lateral bending (16% greater; P =0.03), and right axial rotation (23% greater; P =0.04). Normalized L3-4 IVD ε1 during right lateral bending was greater on average for the FV group than the FP group: Q1, 18% greater; Q2, 12% greater; Q3, 40% greater ( P <0.001); Q4, 9% greater. Normalized ε2 values during left axial rotation were greater in the FV group, the highest increase being 25% in Q3 ( P =0.02). CONCLUSIONS: Facet joint violation during single-level pedicle screw-rod fixation was associated with increased superior adjacent level mobility and alteration of disc surface strains, with significant increases in selected regions and directions of loading.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Articulação Zigapofisária , Humanos , Articulação Zigapofisária/cirurgia , Fusão Vertebral/efeitos adversos , Fenômenos Biomecânicos , Cadáver , Amplitude de Movimento Articular , Vértebras Lombares/cirurgia
9.
Int J Spine Surg ; 17(4): 484-491, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37076254

RESUMO

BACKGROUND: The objective of this study was to assess the pullout force of a novel sharp-tipped screw developed for single-step, minimally invasive pedicle screw placement guided by neuronavigation compared with the pullout force for traditional screws. METHODS: A total of 60 human cadaveric lumbar pedicles were studied. Three different screw insertion techniques were compared: (A) Jamshidi needle and Kirschner wire without tapping; (B) Jamshidi needle and Kirschner wire with tapping; and (C) sharp-tipped screw insertion. Pullout tests were performed at a displacement rate of 10 mm/min recorded at 20 Hz. Mean values of these parameters were compared using paired t tests (left vs right in the same specimen): A vs B, A vs C, and B vs C. Additionally, 3 L1-L5 spine models were used for timing each screw insertion technique for a total of 10 screw insertions for each technique. Insertion times were compared using 1-way analysis of variance. RESULTS: The mean pullout force for insertion technique A was 1462.3 (597.5) N; for technique B, it was 1693.5 (805.0) N; and for technique C, it was 1319.0 (735.7) N. There was no statistically significant difference in pullout force between techniques (P > 0.08). The average insertion time for condition C was significantly less than that for conditions A and B (P < 0.001). CONCLUSIONS: The pullout force of the novel sharp-tipped screw placement technique is equivalent to that of traditional techniques. The sharp-tipped screw placement technique appears biomechanically viable and has the advantage of saving time during insertion. CLINICAL RELEVANCE: Single-step screw placement using high resolution 3-dimensional navigation has the potential to streamline workflow and reduce operative time.

10.
Clin Spine Surg ; 36(6): E247-E251, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36788442

RESUMO

STUDY DESIGN: This was a laboratory investigation. OBJECTIVE: Rod attachment can induce significant pedicle screw-and-rod pre- strain that may predispose the instrumentation to failure. This study investigated how in vitro L5-S1 rod strain and S1 screw strain during rod-screw attachment (pre-strain) compared with strains recorded during pure-moment bending ( test- strain). SUMMARY OF BACKGROUND DATA: The lumbosacral junction is highly vulnerable to construct failure due to rod fatigue fracture, sacral screw pull-out, and screw fatigue fracture. MATERIALS AND METHODS: Twelve cadaveric specimens were instrumented with L2-ilium pedicle screws and rod. Strain gauges on contoured rods and sacral screws recorded strains during sequential rod-to-screw tightening (pre-strains). The same instrumented constructs were immediately tested in a 6-degree-of-freedom apparatus under continuous loading to 7.5 Nm in multidirectional bending while recording instrumentation test-strains. Rod and screw pre-strains and test-strains were compared using 1-way repeated-measures analysis of variance followed by Holm-Sidák paired analysis (significant at P <0.05). RESULTS: The mean first (171±192 µE) and second (322±269 µE) rod attachment pre-strains were comparable to mean test-strains during flexion (265±109 µE) and extension (315±125 µE, P ≥0.13). The mean rod attachment pre-strain was significantly greater than mean test-strains during bidirectional lateral bending (40±32 µE ipsilateral and 39±32 µE contralateral, P <0.001) and axial rotation (72±60 µE ipsilateral and 60±57 µE contralateral, P <0.001). The mean first and second sacral screw pre-strains during rod attachment (1.03±0.66 and 1.39±1.00 Nm, respectively) did not differ significantly ( P =0.41); however, the mean sacral screw pre-strain during final (second) rod attachment was significantly greater than screw test-strains during all directions of movement (≤0.81 Nm, P ≤0.03). CONCLUSIONS: Instrumentation pre-strains imposed during in vitro rod-screw attachment of seemingly well-contoured rods in L2-ilium fixation are comparable to, and at times greater than, strains experienced during in vitro bending. Spine surgeons should be aware of the biomechanical consequences of rod contouring and attachment on construct vulnerability.


Assuntos
Fraturas de Estresse , Parafusos Pediculares , Fusão Vertebral , Humanos , Vértebras Lombares/cirurgia , Sacro/cirurgia , Amplitude de Movimento Articular , Fenômenos Biomecânicos
11.
J Neurosurg Case Lessons ; 4(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471576

RESUMO

BACKGROUND: Spinal hematomas are a rare entity with broad etiologies, which stem from idiopathic, tumor-related, and vascular malformation etiologies. Less common causes include traumatic blunt nonpenetrating spinal hematomas with very few cases being reported. In the present manuscript presents a case report and review of the literature of a rare traumatic entity of a cervical subarachnoid hematoma in association with Brown-Séquard syndrome in a patient on anticoagulants. Searches were performed on PubMed and Embase for specific terms related. OBSERVATIONS: A well-documented case of an 83-year-old female taking anticoagulants with traumatic cervical subarachnoid hematoma presenting as Brown-Séquard syndrome was reported. Six similar cases were identified, scrutinized, and analyzed in the literature review. LESSONS: Traumatic blunt nonpenetrating cervical spine subarachnoid hematomas are a rare entity that can happen more specifically in anticoagulant users and in patients with arthritic changes and stenosis of the spinal canal. Rapid neurological deterioration and severe disability warrant early aggressive surgical treatment. This report has the intention to record this case in the medical literature for registry purposes.

12.
Neurospine ; 19(3): 828-837, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36203305

RESUMO

OBJECTIVE: The high mechanical stress zone at the sudden transition from a rigid to flexible region is involved in proximal junctional kyphosis (PJK) physiopathology. We evaluated the biomechanical performance of polyetheretherketone (PEEK) rods used as a nontraditional long semirigid transition phase from a long-segment metallic rod construct to the nonfused thoracic spine. METHODS: Pure moment range of motion (ROM) tests (7.5 Nm) were performed on 7 cadaveric spine segments followed by compression (200 N). Specimens were tested in the following conditions: (1) intact; (2) T10-pelvis pedicle screws and rods (PSRs); and (3) extending the proximal construct to T6 using PEEK rods (PSR+PEEK). T10-11 rod strain, T9 anterolateral bone strain, and T10 screw bending moments were analyzed. RESULTS: At the upper instrumented vertebra (UIV)+1, PSR+PEEK versus PSR significantly decreased ROM in flexion (115%, p = 0.02), extension (104%, p = 0.003), left lateral bending (46%, p = 0.02), and right lateral bending (63%, p = 0.008). Also, at UIV+1, PSR+PEEK versus intact significantly decreased ROM in flexion (111%, p = 0.01) and extension (105%, p = 0.003). The UIV+1 anterior column bone strain was significantly reduced with PSR+PEEK versus PSR during right lateral bending (p = 0.02). Rod strain polarities reversed with PEEK rods in all loading directions except compression. CONCLUSION: Extending a long-segment construct using PEEK rods caused a decrease in adjacent-level hypermobility as a consequence of long-segment immobilization and also redistributed the strain on the UIV and adjacent levels, which might contribute to PJK physiopathology. Further studies are necessary to observe the clinical outcomes of this technique.

13.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233050

RESUMO

The majority of pituitary adenomas occur in a sporadic context, and in the absence of known genetic predisposition. Three common variants at the NEBL (rs2359536), PCDH15 (rs10763170) and CDK8 (rs17083838) loci were previously associated with sporadic pituitary adenomas in the Han Chinese population, but these findings have not yet been replicated in any other population. The aim of this case-control study was to assess if these variants are associated with susceptibility to sporadic pituitary adenomas in the Portuguese population. Genotype and allele frequencies were determined in 570 cases and in 546 controls. The CDK8 rs17083838 minor allele (A allele) was significantly associated with sporadic pituitary adenomas, under an additive (odds ratio (OR) 1.73, 95% confidence interval (CI) 1.19-2.50, p = 0.004) and dominant (OR 1.82, 95% CI 1.24-2.68, p = 0.002) inheritance model. The NEBL rs2359536 and PCDH15 rs10763170 variants were not associated with the overall risk for the disease, although a borderline significant association was observed between the PCDH15 rs10763170 minor allele (T allele) and somatotrophinomas (dominant model, OR 1.55, 95% CI 1.02-2.35, p = 0.035). These findings suggest that the CDK8 rs17083838 variant, and possibly the PCDH15 rs10763170 variant, may increase susceptibility to sporadic pituitary adenomas in the Portuguese population.


Assuntos
Adenoma , Quinase 8 Dependente de Ciclina , Neoplasias Hipofisárias , Adenoma/genética , Estudos de Casos e Controles , Quinase 8 Dependente de Ciclina/genética , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Hipofisárias/genética , Polimorfismo de Nucleotídeo Único , Portugal
14.
Cureus ; 14(7): e26925, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35983384

RESUMO

Paragangliomas (PGLs) are rare neuroendocrine tumors that, when functional, can release excessive catecholamines, causing health conditions ranging from asymptomatic arterial hypertension to life-threatening arrhythmias and cardiogenic shock. Early diagnosis of functional PGLs is extremely important as timely treatment can be curative and prevent vascular sequelae. We describe the clinical case of a 30-year-old woman with arterial hypertension under study, who was presented to the emergency department with a hypertensive crisis that progressed to adrenergic shock, in the context of a functional PGL.

15.
World Neurosurg ; 166: e656-e663, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35872128

RESUMO

BACKGROUND: Adjacent level degeneration is a precursor to construct failure in adult spinal deformity surgery, but whether construct design affects adjacent level degeneration risk remains unclear. Here we present a biomechanical profile of common deformity correction constructs and assess adjacent level biomechanics. METHODS: Standard nondestructive flexibility tests (7.5 Nm) were performed on 21 cadaveric specimens: 14 pedicle subtraction osteotomies (PSOs) and 7 anterior column realignment (ACR) constructs. The ranges of motion (ROM) at the adjacent free level in flexion, extension, axial rotation, and lateral bending were measured and analyzed. RESULTS: ACR constructs had a lower ROM change on flexion at the proximal adjacent free level than constructs with PSO (1.02 vs. 1.32, normalized to the intact specimen, P < 0.01). Lateral lumbar interbody fusion adjacent to PSO and 4 rods limits ROM at the free level more effectively than transforaminal interbody fusion and 2 rods in correction constructs with PSO. Use of 2 screws to anchor the ACR interbody further decreased ROM at the proximal adjacent free level on flexion, but adding 4 rods in this setting added no further limitation to adjacent segment motion. CONCLUSIONS: ACR constructs have less ROM change at the adjacent level compared to PSO constructs. Among constructs with ACR, anchoring the ACR interbody with 2 screws reduces motion at the proximal adjacent free level. When PSOs are used, lateral lumbar interbody fusion adjacent to the PSO level has a greater reduction in adjacent-segment motion than transforaminal interbody fusion, suggesting that deformity construct configuration influences proximal adjacent-segment biomechanics.


Assuntos
Vértebras Lombares , Fusão Vertebral , Adulto , Fenômenos Biomecânicos , Cadáver , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular , Rotação
16.
Viruses ; 14(7)2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35891431

RESUMO

The occurrence of dengue disease has increased radically in recent decades. Previously, we constructed the pE1D2 and pcTPANS1 DNA vaccines encoding the DENV2 envelope (E) and non-structural 1 (NS1) proteins, respectively. To decrease the number of plasmids in a tetravalent candidate vaccine, we constructed a bicistronic plasmid, pNS1/E/D2, encoding these two proteins simultaneously. We evaluated the protective immunity induced in mice vaccinated with the pNS1/E/D2 candidate and compared to the responses elicited by immunization with the former vaccines isolated or in combination. We transfected BHK-21 cells with the different plasmids and detected recombinant proteins by immunofluorescence and mass spectrometry assays to confirm antigen expression. BALB/c mice were inoculated with the DNA vaccines followed by a lethal DENV2 challenge. ELISA, PRNT50, and IFN-gamma ELISPOT assays were performed for the investigation of the humoral and cellular responses. We observed the concomitant expression of NS1 and E proteins in pNS1/E/D2-transfected cells. All E-based vaccines induced anti-E and neutralizing antibodies. However, anti-NS1 antibodies were only observed after immunization with the pcTPANS1 administered alone or combined with pE1D2. In contrast, splenocytes from pNS1/E/D2- or pcTPANS1 + pE1D2-vaccinated animals responded to NS1- and E-derived synthetic peptides. All the DNA vaccines conferred protection against DENV2.


Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Vacinas de DNA , Animais , Anticorpos Antivirais , Dengue/prevenção & controle , Vacinas contra Dengue/genética , Vírus da Dengue/genética , Imunidade , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de DNA/genética , Proteínas não Estruturais Virais/genética
17.
Rev. méd. Paraná ; 80(1): 1-2, jan. 2022.
Artigo em Português | LILACS | ID: biblio-1381074

RESUMO

A tomografia computadorizada (TC) é exame de escolha para rastreamento de lesões no traumatismo cranioencefálico (TCE). Apesar disso, seu uso rotineiro no TCE leve é controverso O objetivo desta revisão foi avaliar o impacto da aplicação de diretrizes de manejo e conduta de TCE leve quanto à solicitação de TC de crânio. É busca realizada nas bases de dados LILACS, Medline, PubMed, SciELO, utilizando descritores do MeSH e DeCS. A busca inicial identificou 30.191 artigos. Após remoção de publicações duplicadas, seleção pelo título, seleção pelo resumo, restaram 25 publicações, que foram lidas na íntegra e cinco incluídas na presente revisão sistemática. Em conclusão, os artigos analisados apresentaram, em média, redução de 25,8% na solicitação de TC de crânio quando aplicadas as diretrizes, e orientam que protocolos para TCE leve são ferramentas eficientes para auxiliar a prática médica, impactando positivamente quando aplicados na população, devendo sempre ser levado em conta a avaliação clínica.


Computed tomography (CT) is the exam of choice for tracking injuries in traumatic brain injury (TBI). Despite this, its routine use in mild TBI is controversial. The objective of this review was to evaluate the impact of applying guidelines for the management and conduct of mild TBI on the request for CT of the head. A search was carried out in the LILACS, Medline, PubMed, SciELO databases, using MeSH and DeCS descriptors. The initial search identified 30,191 articles. After removal of duplicate publications, selection by title, selection by abstract, 25 publications remained, which were read in full and five were included in this systematic review. In conclusion, the articles analyzed showed, on average, a 25.8% reduction in the request for cranial CT when the guidelines were applied, and guide that protocols for mild TBI are efficient tools to assist medical practice, positively impacting when applied to the population. , and clinical evaluation should always be taken into account.


Assuntos
Humanos , Tomografia Computadorizada por Raios X , Técnicas de Diagnóstico Neurológico , Traumatismos Craniocerebrais , Crânio , Lesões Encefálicas Traumáticas
18.
J Neurosurg Spine ; : 1-10, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35535834

RESUMO

OBJECTIVE: Changes to segmental lordosis at a single level may affect adjacent-level biomechanics and overall spinal alignment with an iatrogenic domino effect commonly seen in adult spinal deformity. This study investigated the effects of different segmental angles of single-level lumbar fixation on stability and principal strain across the surface of the adjacent-level disc. METHODS: Seven human cadaveric L3-S1 specimens were instrumented at L4-5 and tested in 3 conditions: 1) neutral native angle ("neutral"), 2) increasing angle by 5° of lordosis ("lordosis"), and 3) decreasing angle by 5° of kyphosis ("kyphosis"). Pure moment loads (7.5 Nm) were applied in flexion, extension, lateral bending, and axial rotation, followed by 400 N of axial compression alone and together with pure moments. Range of motion (ROM), principal maximum strain (E1), and principal minimum strain (E2) across different surface subregions of the upper adjacent-level disc (L3-4) were optically assessed. Larger magnitudes of either E1 or E2 indicate larger tissue deformations and represent indirect measures of increased stress. RESULTS: At the superior adjacent level, a significant increase in ROM was observed in kyphosis and lordosis versus neutral in flexion (p ≤ 0.001) and extension (p ≤ 0.02). ROM was increased in lordosis versus neutral (p = 0.03) and kyphosis (p = 0.004) during compression. ROM increased in kyphosis versus neutral and lordosis (both p = 0.03) in compression plus extension. Lordosis resulted in increased E1 across the midposterior subregion of the disc (Q3) versus neutral during right lateral bending (p = 0.04); lordosis and kyphosis resulted in decreased E1 in Q3 versus neutral with compression (p ≤ 0.03). Lordosis decreased E1 in Q3 versus neutral during compression plus flexion (p = 0.01), whereas kyphosis increased E1 in all quartiles and increased E2 in the midanterior subregion versus lordosis in compression plus flexion (p ≤ 0.047). Kyphosis decreased E1 in Q3 (p = 0.02) and E2 in the anterior-most subregion of the disc (Q1) (p = 0.006) versus neutral, whereas lordosis decreased E1 in Q3 (p = 0.008) versus neutral in compression plus extension. CONCLUSIONS: Lumbar spine monosegmental fixation with 5° offset from the neutral individual segmental angle altered the motion and principal strain magnitudes at the upper adjacent disc, with induced kyphosis resulting in larger principal strains compared with lordosis. Segmental alignment of single-level fusion influences adjacent-segment biomechanics, and suboptimal alignment may play a role in the clinical development of adjacent-segment disease.

19.
Eur Spine J ; 31(9): 2239-2247, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35524824

RESUMO

PURPOSE: To describe a comprehensive setting of the different alternatives for performing a single position fusion surgery based on the opinion of leading surgeons in the field. METHODS: Between April and May of 2021, a specifically designed two round survey was distributed by mail to a group of leaders in the field of Single Position Surgery (SPS). The questionnaire included a variety of domains which were focused on highlighting tips and recommendations regarding improving the efficiency of the performance of SPS. This includes operation room setting, positioning, use of technology, approach, retractors specific details, intraoperative neuromonitoring and tips for inserting percutaneous pedicle screws in the lateral position. It asked questions focused on Lateral Single Position Surgery (LSPS), Lateral ALIF (LA) and Prone Lateral Surgery (PLS). Strong agreement was defined as an agreement of more than 80% of surgeons for each specific question. The number of surgeries performed in SPS by each surgeon was used as an indirect element to aid in exhibiting the expertise of the surgeons being surveyed. RESULTS: Twenty-four surgeons completed both rounds of the questionnaire. Moderate or strong agreement was found for more than 50% of the items. A definition for Single Position Surgery and a step-by-step recommendation workflow was built to create a better understanding of surgeons who are starting the learning curve in this technique. CONCLUSION: A recommendation of the setting for performing single position fusion surgery procedure (LSPS, LA and PLS) was developed based on a survey of leaders in the field.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Cirurgiões , Humanos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Inquéritos e Questionários
20.
J Biomech ; 135: 111025, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35259657

RESUMO

Few studies have used optical full-field surface strain mapping to study spinal biomechanics. We used a commercial digital imaging correlation (DIC) system to (1) compare posterior surface strains on spinal rods with those obtained from conventional foil strain gauges, (2) quantify bony vertebral body and intervertebral disc (IVD) surface strains on 3 L3-S cadaveric spines during gold-standard flexibility tests (7.5-Nm flexion-extension and 400-N compression), and (3) report our experience with the application and feasibility of DIC to comprehensively map strain in spinal biomechanics. Spinal rods were tested under zero load and using ASTM F1717 standard. For rod strain measures, the largest mean bias offset and baseline noise standard deviation under zero load for DIC were 7.6 µÎµ and 33.7 µÎµ, respectively. For tissue measures, the largest mean bias offset was 8 µÎµ for ε1 and -55 µÎµ for ε2 with baseline noise standard deviations of 19 µÎµ and 26 µÎµ, respectively. On average, DIC rod strain measurements were 5.3% less than strain gauge measurements throughout the load range. Principal IVD and bony surface strains were consistently measurable and showed marked regional differences in strain patterns under different load conditions. Strains measured on spinal rods using DIC techniques reasonably agreed with standard strain gauge measurements. Subregional strain analyses on soft and hard spinal tissues during standard flexibility tests were feasible. Optical strain mapping is a viable, accurate, and promising measurement technique for novel spinal biomechanical studies.


Assuntos
Disco Intervertebral , Vértebras Lombares , Fenômenos Biomecânicos , Biofísica , Humanos , Disco Intervertebral/diagnóstico por imagem , Estresse Mecânico
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