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Validation of the PediBIRN-7 clinical prediction rule for pediatric abusive head trauma. CHILD ABUSE & NEGLECT 2024; 152:106799. [PMID: 38663048 PMCID: PMC11097240 DOI: 10.1016/j.chiabu.2024.106799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/04/2024] [Accepted: 04/08/2024] [Indexed: 05/12/2024]
Abstract
BACKGROUND The PediBIRN-7 clinical prediction rule incorporates the (positive or negative) predictive contributions of completed abuse evaluations to estimate abusive head trauma (AHT) probability after abuse evaluation. Applying definitional criteria as proxies for AHT and non-AHT ground truth, it performed with sensitivity 0.73 (95 % CI: 0.66-0.79), specificity 0.87 (95 % CI: 0.82-0.90), and ROC-AUC 0.88 (95 % CI: 0.85-0.92) in its derivation study. OBJECTIVE To validate the PediBIRN-7's AHT prediction performance in a novel, equivalent, patient population. PARTICIPANTS AND SETTINGS Consecutive, acutely head-injured children <3 years hospitalized for intensive care across eight sites between 2017 and 2020 with completed skeletal surveys and retinal exams (N = 342). METHODS Secondary analysis of an existing, cross-sectional, prospective dataset, including assignment of patient-specific estimates of AHT probability, calculation of AHT prediction performance measures (ROC-AUC, sensitivity, specificity, predictive values), and completion of sensitivity analyses to estimate best- and worst-case prediction performances. RESULTS Applying the same definitional criteria, the PediBIRN-7 performed with sensitivity 0.74 (95 % CI: 0.66-0.81), specificity 0.77 (95 % CI: 0.70-0.83), and ROC-AUC 0.83 (95 % CI: 0.78-0.88). The reduction in ROC-AUC was statistically insignificant (p = .07). Applying physicians' final consensus diagnoses as proxies for AHT and non-AHT ground truth, the PediBIRN-7 performed with sensitivity 0.73 (95 % CI: 0.66-0.79), specificity 0.87 (95 % CI: 0.82-0.90), and ROC-AUC 0.90 (95 % CI: 0.87-0.94). Sensitivity analyses demonstrated minimal changes in rule performance. CONCLUSION The PediBIRN-7's overall AHT prediction performance has been validated in a novel, equivalent, patient population. Its patient-specific estimates of AHT probability can inform physicians' AHT-related diagnostic reasoning after abuse evaluation.
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Retinal hemorrhage variation in inertial versus contact head injuries. CHILD ABUSE & NEGLECT 2024; 149:106606. [PMID: 38134727 DOI: 10.1016/j.chiabu.2023.106606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 12/07/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023]
Abstract
BACKGROUND Abusive head trauma (AHT) is frequently accompanied by dense/extensive retinal hemorrhages to the periphery with or without retinoschisis (complex retinal hemorrhages, cRH). cRH are uncommon without AHT or major trauma. OBJECTIVE The study objectives were to determine whether cRH are associated with inertial vs. contact mechanisms and are primary vs. secondary injuries. PARTICIPANTS AND SETTING This retrospective study utilized a de-identified PediBIRN database of 701 children <3-years-old presenting to intensive care for head trauma. Children with motor vehicle related trauma and preexisting brain abnormalities were excluded. All had imaging showing head injury and a dedicated ophthalmology examination. METHODS Contact injuries included craniofacial soft tissue injuries, skull fractures and epidural hematoma. Inertial injuries included acute impairment or loss of consciousness and/or bilateral and/or interhemispheric subdural hemorrhage. Abuse was defined in two ways, by 1) predetermined criteria and 2) caretaking physicians/multidisciplinary team's diagnostic consensus. RESULTS PediBIRN subjects with cRH frequently experienced inertial injury (99.4 % (308/310, OR = 53.74 (16.91-170.77)) but infrequently isolated contact trauma (0.6 % (2/310), OR = 0.02 (0.0004-0.06)). Inertial injuries predominated over contact trauma among children with cRH sorted AHT by predetermined criteria (99.1 % (237/239), OR = 20.20 (6.09-67.01) vs 0.5 % (2/339), OR = 0.04 (0.01-0.17)). Fifty-nine percent of patients with cRH, <24 h altered consciousness, and inertial injuries lacked imaging evidence of brain hypoxia, ischemia, or swelling. CONCLUSIONS cRH are significantly associated with inertial angular acceleration forces. They can occur without brain hypoxia, ischemia or swelling suggesting they are not secondary injuries.
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Skeletal survey yields in low vs. high risk pediatric patients with skull fractures. CHILD ABUSE & NEGLECT 2023; 139:106130. [PMID: 36905686 PMCID: PMC10120383 DOI: 10.1016/j.chiabu.2023.106130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/17/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND To assess for occult fractures, physicians often opt to obtain skeletal surveys (SS) in young, acutely head-injured patients who present with skull fractures. Data informing optimal decision management are lacking. OBJECTIVE To determine the positive yields of radiologic SS in young patients with skull fractures presumed to be at low vs. high risk for abuse. PARTICIPANTS AND SETTING 476 acutely head injured, skull-fractured patients <3 years hospitalized for intensive care across 18 sites between February 2011 and March 2021. METHODS We conducted a retrospective, secondary analysis of the combined, prospective Pediatric Brain Injury Research Network (PediBIRN) data set. RESULTS 204 (43 %) of 476 patients had simple, linear, parietal skull fractures. 272 (57 %) had more complex skull fracture(s). Only 315 (66 %) of 476 patients underwent SS, including 102 (32 %) patients presumed to be at low risk for abuse (patients who presented with a consistent history of accidental trauma; intracranial injuries no deeper than the cortical brain; and no respiratory compromise, alteration or loss of consciousness, seizures, or skin injuries suspicious for abuse). Only one of 102 low risk patients revealed findings indicative of abuse. In two other low risk patients, SS helped to confirm metabolic bone disease. CONCLUSIONS Less than 1 % of low risk patients under three years of age who presented with simple or complex skull fracture(s) revealed other abusive fractures. Our results could inform efforts to reduce unnecessary skeletal surveys.
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The association of subcortical brain injury and abusive head trauma. CHILD ABUSE & NEGLECT 2022; 134:105917. [PMID: 36308893 DOI: 10.1016/j.chiabu.2022.105917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/21/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Abusive head trauma (AHT) remains a major pediatric problem with diagnostic challenges. A small pilot study previously associated subcortical brain injury with AHT. OBJECTIVES To investigate the association of subcortical injury on neuroimaging with the diagnosis of AHT. PARTICIPANTS AND SETTING Children <3 years with acute TBI admitted to 18 PICUs between 2011 and 2021. METHODS Secondary analysis of existing, combined, de-identified, cross-sectional dataset. RESULTS Deepest location of visible injury was characterized as scalp/skull/epidural (n = 170), subarachnoid/subdural (n = 386), cortical brain (n = 170), or subcortical brain (n = 247) (total n = 973). Subcortical injury was significantly associated with AHT using both physicians' diagnostic impression (OR: 8.41 [95 % CI: 5.82-12.44]) and a priori definitional criteria (OR: 5.99 [95 % CI: 4.31-8.43]). Caregiver reports consistent with the child's gross motor skills and historically consistent with repetition decreased as deepest location of injury increased, p < 0.001. Patients with subcortical injuries were significantly more likely to have traumatic extracranial injuries such as rib fractures (OR 3.36, 95 % CI 2.30-4.92) or retinal hemorrhages (OR 5.97, 95 % CI 4.35-8.24), respiratory compromise (OR 12.12, 95 % CI 8.49-17.62), circulatory compromise (OR 6.71, 95 % CI 4.87-9.29), seizures (OR 3.18, 95 % CI 2.35-4.29), and acute encephalopathy (OR 12.44, 95 % CI 8.16-19.68). CONCLUSIONS Subcortical injury is associated with a diagnosis of AHT, historical inaccuracies concerning for abuse, traumatic extracranial injuries, and increased severity of illness including respiratory and circulatory compromise, seizures, and prolonged loss of consciousness. Presence of subcortical injury should be considered as one component of the complex AHT diagnostic process.
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Lung Ultrasound versus Chest X-Ray for the Detection of Fluid Overload in Critically Ill Children: A Systematic Review. J Pediatr Intensive Care 2022; 11:177-182. [DOI: 10.1055/s-0041-1725123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 01/23/2021] [Indexed: 10/21/2022] Open
Abstract
AbstractFluid overload is a common complication of critical illness, associated with increased morbidity and mortality. Pulmonary fluid status is difficult to evaluate clinically and many clinicians utilize chest X-ray (CXR) to identify fluid overload. Adult data have shown lung ultrasound (LUS) to be a more sensitive modality. Our objective was to determine the performance of LUS for detecting fluid overload, with comparison to CXR, in critically ill children. We conducted a systematic review using multiple electronic databases and included studies from inception to November 15, 2020. The sensitivity and specificity of each test were evaluated. Out of 1,209 studies screened, 4 met eligibility criteria. Overall, CXR is reported to have low sensitivity (44–58%) and moderate specificity (52–94%) to detect fluid overload, while LUS is reported to have high sensitivity (90–100%) and specificity (94–100%). Overall, the quality of evidence was moderate, and the gold standard was different in each study. Our systematic review suggests LUS is more sensitive and specific than CXR to identify pulmonary fluid overload in critically ill children. Considering the clinical burden of fluid overload and the relative ease of obtaining LUS, further evaluation of LUS to diagnose volume overload is warranted.
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An analysis of physicians' diagnostic reasoning regarding pediatric abusive head trauma. CHILD ABUSE & NEGLECT 2022; 129:105666. [PMID: 35567958 PMCID: PMC10724711 DOI: 10.1016/j.chiabu.2022.105666] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 04/26/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Physician diagnoses of abusive head trauma (AHT) have been criticized for circular reasoning and over-reliance on a "triad" of findings. Absent a gold standard, analyses that apply restrictive reference standards for AHT and non-AHT could serve to confirm or refute these criticisms. OBJECTIVES To compare clinical presentations and injuries in patients with witnessed/admitted AHT vs. witnessed non-AHT, and with witnessed/admitted AHT vs. physician diagnosed AHT not witnessed/admitted. To measure the triad's AHT test performance in patients with witnessed/admitted AHT vs. witnessed non-AHT. PARTICIPANTS AND SETTING Acutely head injured patients <3 years hospitalized for intensive care across 18 sites between 2010 and 2021. METHODS Secondary analyses of existing, combined, cross-sectional datasets. Probability values and odds ratios were used to identify and characterize differences. Test performance measures included sensitivity, specificity, and predictive values. RESULTS Compared to patients with witnessed non-AHT (n = 100), patients with witnessed/admitted AHT (n = 58) presented more frequently with respiratory compromise (OR 2.94, 95% CI: 1.50-5.75); prolonged encephalopathy (OR 5.23, 95% CI: 2.51-10.89); torso, ear, or neck bruising (OR 11.87, 95% CI: 4.48-31.48); bilateral subdural hemorrhages (OR 8.21, 95% CI: 3.94-17.13); diffuse brain hypoxia, ischemia, or swelling (OR 6.51, 95% CI: 3.06-13.02); and dense, extensive retinal hemorrhages (OR 7.59, 95% CI: 2.85-20.25). All differences were statistically significant (p ≤ .001). No significant differences were observed in patients with witnessed/admitted AHT (n = 58) vs. patients diagnosed with AHT not witnessed/admitted (n = 438). The triad demonstrated AHT specificity and positive predictive value ≥0.96. CONCLUSIONS The observed differences in patients with witnessed/admitted AHT vs. witnessed non-AHT substantiate prior reports. The complete absence of differences in patients with witnessed/admitted AHT vs. physician diagnosed AHT not witnessed/admitted supports an impression that physicians apply diagnostic reasoning informed by knowledge of previously reported injury patterns. Concern for abuse is justified in patients who present with "the triad."
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Screening for pediatric abusive head trauma: Are three variables enough? CHILD ABUSE & NEGLECT 2022; 125:105518. [PMID: 35082111 PMCID: PMC8842560 DOI: 10.1016/j.chiabu.2022.105518] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 01/10/2022] [Accepted: 01/17/2022] [Indexed: 06/01/2023]
Abstract
BACKGROUND The PediBIRN 4-variable clinical decision rule (CDR) detects abusive head trauma (AHT) with 96% sensitivity in pediatric intensive care (PICU) settings. Preliminary analysis of its performance in Pediatric Emergency Department settings found that elimination of its fourth predictor variable enhanced screening accuracy. OBJECTIVE To compare the AHT screening performances of the "PediBIRN-4" CDR vs. the simplified 3-variable CDR in PICU settings. PARTICIPANTS AND SETTINGS 973 acutely head-injured children <3 years hospitalized for intensive care across 18 sites between February 2011 and March 2021. METHODS Retrospective, secondary analysis of the combined, prospective PediBIRN data sets. AHT definitional criteria and physicians' diagnoses were applied iteratively to sort patients into abusive vs. other head trauma cohorts. Outcome measures of CDR performance included sensitivity, specificity, predictive values, likelihood ratios, ROC AUC, and the correlation between each CDR's patient-specific estimates of AHT probability and the overall positive yield of patients' completed abuse evaluations. RESULTS Applied accurately and consistently, both CDR's would have performed with sensitivity ≥93% and negative predictive value ≥91%. Eliminating the PediBIRN-4's fourth predictor variable resulted in significantly higher specificity (↑'d ≥19%), positive predictive value (↑'d ≥8%), and ROC AUC (↑'d ≥5%), but a 3% reduction in sensitivity. Both CDRs provided patient-specific estimates of abuse probability very strongly correlated with the positive yield of patients' completed abuse evaluations (Pearson's r = 0.95 and 0.91, p = .13). CONCLUSION The PediBIRN 3-variable CDR performed with greater AHT screening accuracy than the 4-variable CDR. Both are good predictors of the results of patients' subsequent completed abuse evaluations.
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A Cluster Randomized Trial to Reduce Missed Abusive Head Trauma in Pediatric Intensive Care Settings. J Pediatr 2021; 236:260-268.e3. [PMID: 33798512 PMCID: PMC8403132 DOI: 10.1016/j.jpeds.2021.03.055] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To estimate the impact of the PediBIRN (Pediatric Brain Injury Research Network) 4-variable clinical decision rule (CDR) on abuse evaluations and missed abusive head trauma in pediatric intensive care settings. STUDY DESIGN This was a cluster randomized trial. Participants included 8 pediatric intensive care units (PICUs) in US academic medical centers; PICU and child abuse physicians; and consecutive patients with acute head injures <3 years (n = 183 and n = 237, intervention vs control). PICUs were stratified by patient volumes, pair-matched, and randomized equally to intervention or control conditions. Randomization was concealed from the biostatistician. Physician-directed, cluster-level interventions included initial and booster training, access to an abusive head trauma probability calculator, and information sessions. Outcomes included "higher risk" patients evaluated thoroughly for abuse (with skeletal survey and retinal examination), potential cases of missed abusive head trauma (patients lacking either evaluation), and estimates of missed abusive head trauma (among potential cases). Group comparisons were performed using generalized linear mixed-effects models. RESULTS Intervention physicians evaluated a greater proportion of higher risk patients thoroughly (81% vs 73%, P = .11) and had fewer potential cases of missed abusive head trauma (21% vs 32%, P = .05), although estimated cases of missed abusive head trauma did not differ (7% vs 13%, P = .22). From baseline (in previous studies) to trial, the change in higher risk patients evaluated thoroughly (67%→81% vs 78%→73%, P = .01), and potential cases of missed abusive head trauma (40%→21% vs 29%→32%, P = .003), diverged significantly. We did not identify a significant divergence in the number of estimated cases of missed abusive head trauma (15%→7% vs 11%→13%, P = .22). CONCLUSIONS PediBIRN-4 CDR application facilitated changes in abuse evaluations that reduced potential cases of missed abusive head trauma in PICU settings. TRIAL REGISTRATION ClinicalTrials.gov: NCT03162354.
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Erratum: All in Your Mind? New-Onset Dysphagia in a Previously Healthy Adolescent Child. J Pediatr Intensive Care 2020; 9:e1. [PMID: 32352429 DOI: 10.1055/s-0040-1701613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
[This corrects the article DOI: 10.1055/s-0039-3401008.].
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All in Your Mind? New-Onset Dysphagia in a Previously Healthy Adolescent Child. J Pediatr Intensive Care 2019; 9:135-138. [PMID: 32351769 DOI: 10.1055/s-0039-3401008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/03/2019] [Indexed: 10/25/2022] Open
Abstract
A healthy 11-year-old male develops fear of choking secondary to progressive dysphagia that began in early childhood. No organic cause is found, and the patient is diagnosed with psychiatric oral aversion. The child is eventually transferred to a psychiatric facility, where a month later he has a possible aspiration event and is transferred to the local emergency room for respiratory distress before being admitted to the intensive care unit. Workup is notable for abnormal findings on brain imaging, and the diagnosis of Alexander's disease is made. This case highlights the importance of complete history-taking and examinations in pediatric patients.
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P.367Comparative analysis of single stranded rAAV vectors expressing human SMN1 in correcting spinal muscular atrophy in mice. Neuromuscul Disord 2019. [DOI: 10.1016/j.nmd.2019.06.529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Spastin regulates VAMP7-containing vesicles trafficking in cortical neurons. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1666-1677. [PMID: 28392418 DOI: 10.1016/j.bbadis.2017.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/04/2017] [Accepted: 04/06/2017] [Indexed: 01/03/2023]
Abstract
Alteration of axonal transport has emerged as a common precipitating factor in several neurodegenerative disorders including Human Spastic Paraplegia (HSP). Mutations of the SPAST (SPG4) gene coding for the spastin protein account for 40% of all autosomal dominant uncomplicated HSP. By cleaving microtubules, spastin regulates several cellular processes depending on microtubule dynamics including intracellular membrane trafficking. Axonal transport is fundamental for the viability of motor neurons which often have very long axons and thus require efficient communication between the cell body and its periphery. Here we found that the anterograde velocity of VAMP7 vesicles, but not that of VAMP2, two vesicular-SNARE proteins implicated in neuronal development, is enhanced in SPG4-KO neurons. We showed that this effect is associated with a slight increase of the level of acetylated tubulin in SPG4-KO neurons and correlates with an enhanced activity of kinesin-1 motors. Interestingly, we demonstrated that an artificial increase of acetylated tubulin by drugs reproduces the effect of Spastin KO on VAMP7 axonal dynamics but also increased its retrograde velocity. Finally, we investigated the effect of microtubule targeting agents which rescue axonal swellings, on VAMP7 and microtubule dynamics. Our results suggest that microtubule stabilizing agents, such as taxol, may prevent the morphological defects observed in SPG4-KO neurons not simply by restoring the altered anterograde transport to basal levels but rather by increasing the retrograde velocity of axonal cargoes.
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Novel presentation of a fourth branchial cleft anomaly in a male infant. Am J Otolaryngol 2010; 31:120-2. [PMID: 20015714 DOI: 10.1016/j.amjoto.2008.09.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 09/16/2008] [Indexed: 11/15/2022]
Abstract
Fourth branchial cleft anomalies are rare congenital disorders of the neck. We describe a case involving a unique presentation of this entity as well as a review of the literature concerning its management.
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Two HIV-1 epidemics in Argentina: different genetic subtypes associated with different risk groups. J Acquir Immune Defic Syndr 2002; 29:422-6. [PMID: 11917249 DOI: 10.1097/00126334-200204010-00015] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This study determined the risk behaviors and viral subtypes of HIV-1 found in 134 heterosexual HIV-seroprevalent maternity patients, 41 of their sexual partners (men who have sex with women [MSW]), and 95 homosexual men (men who have sex with men [MSM]) from Buenos Aires, Argentina. Peripheral blood mononuclear cells (PBMCs) were purified from blood and used for DNA extraction, amplification, and genotyping by the envelope heteroduplex mobility assay (env HMA). Most of the women had been infected by having sex with an already infected partner (84%), whereas most of the male partners had been infected via drug use (76%). Both the patients and their sexual partners were poorly educated, only 30% having completed secondary school. The MSM study subjects, however, were significantly better educated and had a lower prevalence of injecting drug use.Env HMA subtype F was found in 77% (103 of 134) of the maternity patients, with similar rates in their partners (73%). Most of the remaining samples were env subtype B. All but one of the couples was concordant in subtype. In the MSM risk group, however, only 10% were env HMA subtype F. Ninety percent of the MSM samples were subtype B. There are at least two independent epidemics of HIV-1 infection in Buenos Aires, Argentina. One, in heterosexual men and women, is dominated by env subtype F whereas the other, in homosexual men, is dominated by env subtype B, as determined by env HMA.
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Mutations in the Newcastle disease virus hemagglutinin-neuraminidase protein that interfere with its ability to interact with the homologous F protein in the promotion of fusion. Virology 1999; 253:43-54. [PMID: 9887317 DOI: 10.1006/viro.1998.9501] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent evidence suggests that the attachment (HN) and fusion (F) glycoproteins of Newcastle disease virus interact at the cell surface in a virus-specific manner to promote syncytium formation. Consistent with the existence of such an interaction, we have shown that it is possible to coimmunoprecipitate (co-IP) the two proteins from the surface of transiently expressing cells using a monoclonal antibody to either protein. Further, we show that a point mutation in the globular domain of HN that abolishes its receptor recognition and neuraminidase (NA) and fusion activities also abolishes its ability to interact with F in the co-IP assay. The mechanism by which this mutation might interfere with the interaction between the two proteins is discussed in terms of the postulate that recognition by HN of cellular receptors triggers its interaction with F and the apparently conflicting evidence for an interaction between the two proteins in the endoplasmic reticulum. Also, characterization of a set of chimeric HN proteins, having short overlapping sequences from a heterologous HN protein in the F-specific domain in the protein stalk, reveals that a weakened interaction between HN and F is still sufficient to trigger fusion.
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Valgus knee stress in lumbosacral myelomeningocele: a gait-analysis evaluation. J Pediatr Orthop 1998; 18:428-33. [PMID: 9661845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Twenty-five independent community-ambulating patients with lumbosacral-level myelomeningocele (N = 50 limbs) underwent gait analysis. The limbs of these patients were divided into two groups based on thigh-foot angle (TFA): Group I (n = 20) had marked external tibial torsion, TFA > or = 20 degrees, and group II had TFA between 10 and 20 degrees. Ten limbs were excluded because of neutral or internal alignment. Twenty normal limbs with TFA = 10 degrees served as controls. An abnormal internal varus knee stress during stance was identified in all group I limbs and 12 (70%) of 20 limbs group II limbs compared with controls, which demonstrated an internal valgus stress. This internal varus moment was greater in group I limbs than in the abnormal limbs in group II (p < 0.05). Knee flexion was the only other parameter found to correlate with this stress and only in group I limbs. We conclude that (a) in this patient group, increased external tibial torsion is likely to result in an abnormal internal varus knee stress; (b) TFA > 20 degrees appears significantly to increase this stress; and (c) knee flexion is an important related parameter, but only in limbs with TFA between 10 and 20 degrees. We believe that this abnormal stress may predispose the knee to late arthrosis and that derotational osteotomies to normalize the TFA may prove to have a favorable long-term effect.
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[Endometriosis of the lower abdominal wall. Report of two cases secondary to cesarean section]. MINERVA GINECOLOGICA 1990; 42:283-5. [PMID: 2143273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The paper describes two cases of cutaneous endometriosis in correspondence with the surgical scar following cesarean section. The cases formed part of a series of 500 abdominal operations performed during the period 1988-89, of which about 200 were cesarean sections, with a 1% frequency. In line with the hypothesis regarding the spread of endometrial tissue during surgery and with that concerning peritoneal metaplasia, the authors recommend paying special attention during the technical procedure of extracting the fetus, and performing an introflexed suture of the uterine incision and of the parietal peritoneum.
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[Use of ofloxacin in 45 cases of infection of the lower urinary tract in women]. MINERVA GINECOLOGICA 1989; 41:541-2. [PMID: 2622580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Forty-five female patients affected by lower urinary tract infections without secondary complications were examined. Ofloxacin was administered in three different dosages in order to evaluate drug efficacy and tolerance: 600 mg/day for 3 days in 22 cases; 300 mg/day for 3 days in 22 cases; 600 mg/day for 5 days in 1 case. Adverse effects were insignificant; clinical remission was virtually complete and urine tests proved negative in 98% of cases. On the basis of these findings it is possible to state that Ofloxacin therapy is efficacious in lower urinary tract infections without secondary complications in women.
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Abstract
One approach to overcome the problem of histoincompatibility in bone marrow transplantation is to use T cell depleted marrow from a haploidentical donor in an attempt to ameliorate graft-versus-host disease. Since the T cell requirements for normal hematopoiesis are uncertain, experiments were performed to study the effects of E rosette-T cell depletion on in vitro growth of hematopoietic progenitor cells. Marrow mononuclear cells were cultured in a modified CFU-GEMM assay before and after T cell depletion. The number of 7 day granulocytic and erythrocytic colonies, and 14 day granulocytic, erythrocytic and mixed colonies were enumerated and expressed in terms of colonies per 10(5) non T cells plated. T cell depletion did not result in decreased proliferation of any of these progenitors save possibly for 14 day granulocytic colonies in one of four experiments. In two cases, T cell depletion resulted in increased growth of progenitor cells. Three of four patients transplanted with T cell depleted haploidentical marrow cells engrafted. It is concluded that E rosette depletion of T cells from marrow does not decrease the potential of these cells to establish hematopoiesis in vitro or in vivo.
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Relationship of the growth of leukemic cells in vitro to the outcome of therapy for acute nonlymphocytic leukemia. Cancer Res 1984; 44:1712-7. [PMID: 6704977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Bone marrow cells obtained from 166 patients with acute nonlymphocytic leukemia were cloned in vitro. The number and size of clones produced differed among patients and was unrelated to French-American-British type of leukemia, to patient age, to whether the patient was studied at the time of initial diagnosis or at relapse, or to the cytogenetic (normal or abnormal metaphases) or cell cycle characteristics of the leukemic bone marrow cells. The ability of leukemic cells to clone in vitro was associated with poor response to therapy in vivo, with the remission rate being inversely related to cloning efficiency of the leukemic cells, and with remission durations being inversely correlated with the size of the cluster/colonies formed in vitro. Only an occasional patient whose marrow cells produced clonal growth in vitro and in whom cytogenetic abnormalities were detected entered complete remission with conventional remission induction therapy. Measurement of the clonogenic potential in vitro of leukemic marrow cells together with their cytogenetic type may help to distinguish between patients who should and should not receive cytosine arabinoside/anthracycline antibiotic remission induction therapy and patients who do and do not require intensive remission consolidation chemotherapy.
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[Behavior of threonine deaminase and of threonine dehydrogenase in the liver of rats treated with nicotinamide]. BOLLETTINO DELLA SOCIETA ITALIANA DI BIOLOGIA SPERIMENTALE 1973; 49:757-61. [PMID: 4275468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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