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1.
Am J Epidemiol ; 192(6): 895-907, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702469

RESUMO

Concerns about the duration of protection conferred by coronavirus disease 2019 (COVID-19) vaccines have arisen in postlicensure evaluations. "Depletion of susceptibles," a bias driven by differential accrual of infection among vaccinated and unvaccinated individuals, may obscure vaccine effectiveness (VE) estimates, hindering interpretation. We enrolled California residents who received molecular SARS-CoV-2 tests in a matched, test-negative design, case-control study to estimate VE of mRNA-based COVID-19 vaccines between February 23 and December 5, 2021. We analyzed waning protection following 2 vaccine doses using conditional logistic regression models. Additionally, we used data from a population-based serological study to adjust for "depletion-of-susceptibles" bias and estimated VE for 3 doses, by time since second dose receipt. Pooled VE of BNT162b2 and mRNA-1273 against symptomatic SARS-CoV-2 infection was 91.3% (95% confidence interval (CI): 83.8, 95.4) at 14 days after second-dose receipt and declined to 50.8% (95% CI: 19.7, 69.8) at 7 months. Adjusting for depletion-of-susceptibles bias, we estimated VE of 53.2% (95% CI: 23.6, 71.2) at 7 months after primary mRNA vaccination series. A booster dose of BN162b2 or mRNA-1273 increased VE to 95.0% (95% CI: 82.8, 98.6). These findings confirm that observed waning of protection is not attributable to epidemiologic bias and support ongoing efforts to administer additional vaccine doses to mitigate burden of COVID-19.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Humanos , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos de Casos e Controles , Eficácia de Vacinas , SARS-CoV-2/genética , RNA Mensageiro
2.
Clin Infect Dis ; 74(8): 1382-1389, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-34282839

RESUMO

BACKGROUND: Estimates of coronavirus disease 2019 (COVID-19) vaccine effectiveness under real-world conditions, and understanding of barriers to uptake, are necessary to inform vaccine rollout. METHODS: We enrolled cases (testing positive) and controls (testing negative) from among the population whose SARS-CoV-2 molecular diagnostic test results from 24 February to 29 April 2021 were reported to the California Department of Public Health. Participants were matched on age, sex, and geographic region. We assessed participants' self-reported history of mRNA-based COVID-19 vaccine receipt (BNT162b2 and mRNA-1273). Participants were considered fully vaccinated 2 weeks after second dose receipt. Among unvaccinated participants, we assessed willingness to receive vaccination. We measured vaccine effectiveness (VE) via the matched odds ratio of prior vaccination, comparing cases with controls. RESULTS: We enrolled 1023 eligible participants aged ≥18 years. Among 525 cases, 71 (13.5%) received BNT162b2 or mRNA-1273; 20 (3.8%) were fully vaccinated with either product. Among 498 controls, 185 (37.1%) received BNT162b2 or mRNA-1273; 86 (16.3%) were fully vaccinated with either product. Two weeks after second dose receipt, VE was 87.0% (95% confidence interval: 68.6-94.6%) and 86.2% (68.4-93.9%) for BNT162b2 and mRNA-1273, respectively. Fully vaccinated participants receiving either product experienced 91.3% (79.3-96.3%) and 68.3% (27.9-85.7%) VE against symptomatic and asymptomatic infection, respectively. Among unvaccinated participants, 42.4% (159/375) residing in rural regions and 23.8% (67/281) residing in urban regions reported hesitancy to receive COVID-19 vaccination. CONCLUSIONS: Authorized mRNA-based vaccines are effective at reducing documented SARS-CoV-2 infections within the general population of California. Vaccine hesitancy presents a barrier to reaching coverage levels needed for herd immunity.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Adulto , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , California/epidemiologia , Humanos , RNA Mensageiro , SARS-CoV-2/genética , Vacinas de mRNA
3.
Clin Infect Dis ; 75(1): e276-e288, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34932817

RESUMO

BACKGROUND: Non-pharmaceutical interventions (NPIs) are recommended for COVID-19 prevention. However, the effectiveness of NPIs in preventing SARS-CoV-2 transmission remains poorly quantified. METHODS: We conducted a test-negative design case-control study enrolling cases (testing positive for SARS-CoV-2) and controls (testing negative) with molecular SARS-CoV-2 diagnostic test results reported to California Department of Public Health between 24 February-12 November, 2021. We used conditional logistic regression to estimate adjusted odds ratios (aORs) of case status among participants who reported contact with an individual known or suspected to have been infected with SARS-CoV-2 ("high-risk exposure") ≤14 days before testing. RESULTS: 751 of 1448 cases (52%) and 255 of 1443 controls (18%) reported high-risk exposures ≤14 days before testing. Adjusted odds of case status were 3.02-fold (95% confidence interval: 1.75-5.22) higher when high-risk exposures occurred with household members (vs. other contacts), 2.10-fold (1.05-4.21) higher when exposures occurred indoors (vs. outdoors only), and 2.15-fold (1.27-3.67) higher when exposures lasted ≥3 hours (vs. shorter durations) among unvaccinated and partially-vaccinated individuals; excess risk associated with such exposures was mitigated among fully-vaccinated individuals. Cases were less likely than controls to report mask usage during high-risk exposures (aOR = 0.50 [0.29-0.85]). The adjusted odds of case status was lower for fully-vaccinated (aOR = 0.25 [0.15-0.43]) participants compared to unvaccinated participants. Benefits of mask usage were greatest among unvaccinated and partially-vaccinated participants, and in interactions involving non-household contacts or interactions occurring without physical contact. CONCLUSIONS: NPIs reduced the likelihood of SARS-CoV-2 infection following high-risk exposure. Vaccine effectiveness was substantial for partially and fully vaccinated persons.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos de Casos e Controles , Humanos , SARS-CoV-2
4.
Am J Public Health ; 112(8): 1180-1190, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35830667

RESUMO

Objectives. To describe which industries have the highest burden of COVID-19 outbreaks in California. Methods. We assigned US census industry codes to COVID-19 outbreaks reported to the California Department of Public Health (CDPH) from January 1, 2020, to August 31, 2021, and determined numbers of outbreaks, numbers of outbreak-associated cases, and outbreak incidence levels by industry. We determined characteristics of outbreak-associated cases using individual case data linked to COVID-19 outbreaks. Results. Local health departments reported 19 893 COVID-19 outbreaks and 300 379 outbreak-associated cases to CDPH. The most outbreaks (47.8%) and outbreak-associated cases (54.8%) occurred in the health care and social assistance sector, where outbreak incidence levels were highest in skilled nursing facilities and residential care facilities (1306 and 544 outbreaks per 1000 establishments, respectively). High proportions of outbreaks also occurred in the retail trade (8.6%) and manufacturing (7.9%) sectors. Demographics of outbreak-associated cases varied across industries. Conclusions. Certain California industries, particularly in the health care, manufacturing, and retail sectors, have experienced a high burden of COVID-19 outbreaks during the pandemic. Public Health Implications. Tracking COVID-19 outbreaks by industry may help target prevention efforts, including workforce vaccination. (Am J Public Health. 2022;112(8):1180-1190. https://doi.org/10.2105/AJPH.2022.306862).


Assuntos
COVID-19 , COVID-19/epidemiologia , California/epidemiologia , Surtos de Doenças/prevenção & controle , Humanos , Pandemias/prevenção & controle , Local de Trabalho
5.
MMWR Morb Mortal Wkly Rep ; 71(6): 212-216, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35143470

RESUMO

The use of face masks or respirators (N95/KN95) is recommended to reduce transmission of SARS-CoV-2, the virus that causes COVID-19 (1). Well-fitting face masks and respirators effectively filter virus-sized particles in laboratory conditions (2,3), though few studies have assessed their real-world effectiveness in preventing acquisition of SARS-CoV-2 infection (4). A test-negative design case-control study enrolled randomly selected California residents who had received a test result for SARS-CoV-2 during February 18-December 1, 2021. Face mask or respirator use was assessed among 652 case-participants (residents who had received positive test results for SARS-CoV-2) and 1,176 matched control-participants (residents who had received negative test results for SARS-CoV-2) who self-reported being in indoor public settings during the 2 weeks preceding testing and who reported no known contact with anyone with confirmed or suspected SARS-CoV-2 infection during this time. Always using a face mask or respirator in indoor public settings was associated with lower adjusted odds of a positive test result compared with never wearing a face mask or respirator in these settings (adjusted odds ratio [aOR] = 0.44; 95% CI = 0.24-0.82). Among 534 participants who specified the type of face covering they typically used, wearing N95/KN95 respirators (aOR = 0.17; 95% CI = 0.05-0.64) or surgical masks (aOR = 0.34; 95% CI = 0.13-0.90) was associated with significantly lower adjusted odds of a positive test result compared with not wearing any face mask or respirator. These findings reinforce that in addition to being up to date with recommended COVID-19 vaccinations, consistently wearing a face mask or respirator in indoor public settings reduces the risk of acquiring SARS-CoV-2 infection. Using a respirator offers the highest level of personal protection against acquiring infection, although it is most important to wear a mask or respirator that is comfortable and can be used consistently.


Assuntos
COVID-19/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Máscaras , Respiradores N95 , Adolescente , Adulto , Idoso , COVID-19/diagnóstico , Teste para COVID-19 , California/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto Jovem
6.
MMWR Morb Mortal Wkly Rep ; 71(4): 125-131, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35085222

RESUMO

By November 30, 2021, approximately 130,781 COVID-19-associated deaths, one in six of all U.S. deaths from COVID-19, had occurred in California and New York.* COVID-19 vaccination protects against infection with SARS-CoV-2 (the virus that causes COVID-19), associated severe illness, and death (1,2); among those who survive, previous SARS-CoV-2 infection also confers protection against severe outcomes in the event of reinfection (3,4). The relative magnitude and duration of infection- and vaccine-derived protection, alone and together, can guide public health planning and epidemic forecasting. To examine the impact of primary COVID-19 vaccination and previous SARS-CoV-2 infection on COVID-19 incidence and hospitalization rates, statewide testing, surveillance, and COVID-19 immunization data from California and New York (which account for 18% of the U.S. population) were analyzed. Four cohorts of adults aged ≥18 years were considered: persons who were 1) unvaccinated with no previous laboratory-confirmed COVID-19 diagnosis, 2) vaccinated (14 days after completion of a primary COVID-19 vaccination series) with no previous COVID-19 diagnosis, 3) unvaccinated with a previous COVID-19 diagnosis, and 4) vaccinated with a previous COVID-19 diagnosis. Age-adjusted hazard rates of incident laboratory-confirmed COVID-19 cases in both states were compared among cohorts, and in California, hospitalizations during May 30-November 20, 2021, were also compared. During the study period, COVID-19 incidence in both states was highest among unvaccinated persons without a previous COVID-19 diagnosis compared with that among the other three groups. During the week beginning May 30, 2021, compared with COVID-19 case rates among unvaccinated persons without a previous COVID-19 diagnosis, COVID-19 case rates were 19.9-fold (California) and 18.4-fold (New York) lower among vaccinated persons without a previous diagnosis; 7.2-fold (California) and 9.9-fold lower (New York) among unvaccinated persons with a previous COVID-19 diagnosis; and 9.6-fold (California) and 8.5-fold lower (New York) among vaccinated persons with a previous COVID-19 diagnosis. During the same period, compared with hospitalization rates among unvaccinated persons without a previous COVID-19 diagnosis, hospitalization rates in California followed a similar pattern. These relationships changed after the SARS-CoV-2 Delta variant became predominant (i.e., accounted for >50% of sequenced isolates) in late June and July. By the week beginning October 3, compared with COVID-19 cases rates among unvaccinated persons without a previous COVID-19 diagnosis, case rates among vaccinated persons without a previous COVID-19 diagnosis were 6.2-fold (California) and 4.5-fold (New York) lower; rates were substantially lower among both groups with previous COVID-19 diagnoses, including 29.0-fold (California) and 14.7-fold lower (New York) among unvaccinated persons with a previous diagnosis, and 32.5-fold (California) and 19.8-fold lower (New York) among vaccinated persons with a previous diagnosis of COVID-19. During the same period, compared with hospitalization rates among unvaccinated persons without a previous COVID-19 diagnosis, hospitalization rates in California followed a similar pattern. These results demonstrate that vaccination protects against COVID-19 and related hospitalization, and that surviving a previous infection protects against a reinfection and related hospitalization. Importantly, infection-derived protection was higher after the Delta variant became predominant, a time when vaccine-induced immunity for many persons declined because of immune evasion and immunologic waning (2,5,6). Similar cohort data accounting for booster doses needs to be assessed, as new variants, including Omicron, circulate. Although the epidemiology of COVID-19 might change with the emergence of new variants, vaccination remains the safest strategy to prevent SARS-CoV-2 infections and associated complications; all eligible persons should be up to date with COVID-19 vaccination. Additional recommendations for vaccine doses might be warranted in the future as the virus and immunity levels change.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/epidemiologia , COVID-19/prevenção & controle , Hospitalização/estatística & dados numéricos , SARS-CoV-2/imunologia , Vacinação/estatística & dados numéricos , Adulto , California/epidemiologia , Estudos de Coortes , Humanos , Incidência , Pessoa de Meia-Idade , New York/epidemiologia
7.
Clin Infect Dis ; 73(9): 1617-1624, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33993217

RESUMO

BACKGROUND: Since the introduction of Haemophilus influenzae serotype b (Hib) conjugate vaccines in the United States, invasive H. influenzae disease epidemiology has changed, and racial disparities have not been recently described. METHODS: Active population- and laboratory-based surveillance for H. influenzae was conducted through Active Bacterial Core surveillance at 10 US sites. Data from 2008-2017 were used to estimate projected nationwide annual incidence, as cases per 100 000. RESULTS: During 2008-2017, Active Bacterial Core surveillance identified 7379 H. influenzae cases. Of 6705 patients (90.9%) with reported race, 76.2% were White, 18.6% were Black, 2.8% were Asian/Pacific Islander, and 2.4% were American Indian or Alaska Native (AI/AN). The nationwide annual incidence was 1.8 cases/100 000. By race, incidence was highest among AI/AN populations (3.1) and lowest among Asian/Pacific Islander populations (0.8). Nontypeable H. influenzae caused the largest incidence within all races (1.3), with no striking disparities identified. Among AI/AN children aged <5 years, incidence of H. influenzae serotype a (Hia) was 16.7 times higher and Hib incidence was 22.4 times higher than among White children. Although Hia incidence was lower among White and Black populations than among AI/AN populations, Hia incidence increased 13.6% annually among White children and 40.4% annually among Black children aged <5 years. CONCLUSIONS: While nontypeable H. influenzae causes the largest H. influenzae burden overall, AI/AN populations experience disproportionately high rates of Hia and Hib, with the greatest disparity among AI/AN children aged <5 years. Prevention tools are needed to reduce disparities affecting AI/AN children and address increasing Hia incidence in other communities.


Assuntos
Infecções por Haemophilus , Vacinas Anti-Haemophilus , Haemophilus influenzae tipo b , Criança , Infecções por Haemophilus/epidemiologia , Haemophilus influenzae , Humanos , Incidência , Lactente , Sorogrupo , Estados Unidos/epidemiologia
8.
Clin Infect Dis ; 73(11): e3718-e3726, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-32803254

RESUMO

BACKGROUND: Reported outbreaks of invasive group A Streptococcus (iGAS) infections among people who inject drugs (PWID) and people experiencing homelessness (PEH) have increased, concurrent with rising US iGAS rates. We describe epidemiology among iGAS patients with these risk factors. METHODS: We analyzed iGAS infections from population-based Active Bacterial Core surveillance (ABCs) at 10 US sites from 2010 to 2017. Cases were defined as GAS isolated from a normally sterile site or from a wound in patients with necrotizing fasciitis or streptococcal toxic shock syndrome. GAS isolates were emm typed. We categorized iGAS patients into four categories: injection drug use (IDU) only, homelessness only, both, and neither. We calculated annual change in prevalence of these risk factors using log binomial regression models. We estimated national iGAS infection rates among PWID and PEH. RESULTS: We identified 12 386 iGAS cases; IDU, homelessness, or both were documented in ~13%. Skin infections and acute skin breakdown were common among iGAS patients with documented IDU or homelessness. Endocarditis was 10-fold more frequent among iGAS patients with documented IDU only versus those with neither risk factor. Average percentage yearly increase in prevalence of IDU and homelessness among iGAS patients was 17.5% and 20.0%, respectively. iGAS infection rates among people with documented IDU or homelessness were ~14-fold and 17- to 80-fold higher, respectively, than among people without those risks. CONCLUSIONS: IDU and homelessness likely contribute to increases in US incidence of iGAS infections. Improving management of skin breakdown and early recognition of skin infection could prevent iGAS infections in these patients.


Assuntos
Usuários de Drogas , Fasciite Necrosante , Pessoas Mal Alojadas , Infecções Estreptocócicas , Fasciite Necrosante/epidemiologia , Humanos , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes , Estados Unidos/epidemiologia
9.
Clin Infect Dis ; 73(2): e371-e379, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32589699

RESUMO

BACKGROUND: Haemophilus influenzae serotype a (Hia) can cause invasive disease similar to serotype b; no Hia vaccine is available. We describe the epidemiology of invasive Hia disease in the United States overall and specifically in Alaska during 2008-2017. METHODS: Active population- and laboratory-based surveillance for invasive Hia disease was conducted through Active Bacterial Core surveillance sites and from Alaska statewide invasive bacterial disease surveillance. Sterile-site isolates were serotyped via slide agglutination or real-time polymerase chain reaction. Incidences in cases per 100 000 were calculated. RESULTS: From 2008 to 2017, an estimated average of 306 invasive Hia disease cases occurred annually in the United States (estimated annual incidence: 0.10); incidence increased by an average of 11.1% annually. Overall, 42.7% of cases were in children aged <5 years (incidence: 0.64), with highest incidence among children aged <1 year (1.60). Case fatality was 7.8% overall and was highest among adults aged ≥65 years (15.1%). Among children aged <5 years, the incidence was 17 times higher among American Indian and Alaska Native (AI/AN) children (8.29) than among children of all other races combined (0.49). In Alaska, incidences among all ages (0.68) and among children aged <1 year (24.73) were nearly 6 and 14 times higher, respectively, than corresponding US incidences. Case fatality in Alaska was 10.2%, and the vast majority (93.9%) of cases occurred among AI/AN. CONCLUSIONS: Incidence of invasive Hia disease has increased since 2008, with the highest burden among AI/AN children. These data can inform prevention strategies, including Hia vaccine development.


Assuntos
Infecções por Haemophilus , Adulto , Alaska/epidemiologia , Criança , Infecções por Haemophilus/epidemiologia , Haemophilus influenzae/imunologia , Humanos , Incidência , Sorogrupo , Sorotipagem , Estados Unidos/epidemiologia , Vacinas Conjugadas
10.
Annu Rev Pharmacol Toxicol ; 58: 583-601, 2018 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28992429

RESUMO

Over 70% of Americans take some form of dietary supplement every day, and the supplement industry is currently big business, with a gross of over $28 billion. However, unlike either foods or drugs, supplements do not need to be registered or approved by the US Food and Drug Administration (FDA) prior to production or sales. Under the Dietary Supplement Health and Education Act of 1994, the FDA is restricted to adverse report monitoring postmarketing. Despite widespread consumption, there is limited evidence of health benefits related to nutraceutical or supplement use in well-nourished adults. In contrast, a small number of these products have the potential to produce significant toxicity. In addition, patients often do not disclose supplement use to their physicians. Therefore, the risk of adverse drug-supplement interactions is significant. An overview of the major supplement and nutraceutical classes is presented here, together with known toxic effects and the potential for drug interactions.


Assuntos
Suplementos Nutricionais/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Animais , Interações Medicamentosas/fisiologia , Humanos , Estados Unidos , United States Food and Drug Administration
11.
BMC Public Health ; 21(1): 1435, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289822

RESUMO

BACKGROUND: Newly reported hepatitis C virus (HCV) infections in California increased 50% among people 15-29 years of age between 2014 and 2016. National estimates suggest this increase was due to the opioid epidemic and associated increases in injection drug use. However, most of California's 61 local health jurisdictions (LHJs) do not routinely investigate newly reported HCV infections, so these individuals' risk factors for infection are not well understood. We sought to describe the demographics, risk behaviors, and utilization of harm reduction services in California's fastest-rising age group of people with newly reported hepatitis C infections to support targeted HCV prevention and treatment strategies. METHODS: California Department of Public Health invited LHJs to participate in enhanced surveillance if they met criteria indicating heightened population risk for HCV infection among people ages 15-29. From June-December 2018, eight LHJs contacted newly reported HCV cases by phone using a structured questionnaire. RESULTS: Among 472 total HCV cases who met the inclusion criteria, 114 (24%) completed an interview. Twenty-seven percent of respondents (n = 31) had ever been incarcerated, of whom 29% received a tattoo/piercing and 39% injected drugs while incarcerated. Among people who injected drugs (PWID)-36% (n = 41) of all respondents-68% shared injection equipment and many lacked access to harm reduction services: 37% knew of or ever used a needle exchange and 44% ever needed naloxone during an overdose but did not have it. Heroin was the most frequently reported injected drug (n = 30), followed by methamphetamine (n = 18). Pre-diagnosis HCV risk perception varied significantly by PWID status and race/ethnicity: 76% of PWID vs. 8% of non-PWID (p < 0.001), and 44% of non-Hispanic White respondents vs. 22% of people of color (POC) respondents (p = 0.011), reported thinking they were at risk for HCV before diagnosis. Eighty-nine percent of all respondents reported having health insurance, although only two had taken HCV antiviral medications. CONCLUSIONS: Among young people with HCV, we found limited pre-diagnosis HCV risk perception and access to harm reduction services, with racial/ethnic disparities. Interventions to increase harm reduction services awareness, access, and utilization among young PWID, especially young PWID of color, may be warranted.


Assuntos
Hepatite C , Abuso de Substâncias por Via Intravenosa , Adolescente , Adulto , California/epidemiologia , Redução do Dano , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Humanos , Percepção , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto Jovem
12.
J Pharmacol Exp Ther ; 373(3): 337-346, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32213546

RESUMO

Bone loss in response to alcohol intake has previously been hypothesized to be mediated by excessive production of reactive oxygen species via NADPH oxidase (Nox) enzymes. Nox4 is one of several Nox enzymes expressed in bone. We investigated the role of Nox4 in the chondro-osteoblastic lineage of the long bones in mice during normal chow feeding and during chronic ethanol feeding for 90 days. We generated mice with a genotype (PrxCre +/- Nox4 fl/fl) allowing conditional knockout of Nox4 in the limb bud mesenchyme. Adult mice had 95% knockdown of Nox4 expression in the femoral shafts. For mice on regular chow, only whole-body Nox4 knockout mice had clearly increased cortical thickness and bone mineral density in the tibiae. When chronically fed a liquid diet with and without ethanol, conditional Nox4 knockout mice had slightly reduced dimensions of the cortical and trabecular regions of the tibiae (P < 0.1). The ethanol diet caused a significant reduction in cortical bone area and cortical thickness relative to a control diet without ethanol (P < 0.05). The ethanol diet further reduced gene expression of Frizzled related protein (Frzb), myosin heavy chain 3, and several genes encoding collagen and other major structural bone proteins (P < 0.05), whereas the Nox4 genotype had no effects on these genes. In conclusion, Nox4 expression from both mesenchymal and nonmesenchymal cell lineages appears to exert subtle effects on bone. However, chronic ethanol feeding reduces cortical bone mass and cortical gene expression of major structural bone proteins in a Nox4-independent manner. SIGNIFICANCE STATEMENT: Excessive alcohol intake contributes to osteopenia and osteoporosis, with oxidative stress caused by the activity of NADPH oxidases hypothesized to be a mediator. We tested the role of NADPH oxidase (Nox) 4 in osteoblast precursors in the long bones of mice with a conditional Nox4 knockout model. We found that Nox4 exerted effects independent of alcohol intake, and ethanol effects on bone were Nox4-independent.


Assuntos
Osso e Ossos/efeitos dos fármacos , Etanol/administração & dosagem , Expressão Gênica/efeitos dos fármacos , NADPH Oxidase 4/genética , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/genética , Feminino , Genótipo , Masculino , Camundongos , Camundongos Knockout , NADPH Oxidases/genética , Osteoblastos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo
13.
Arch Toxicol ; 94(2): 389-399, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31820026

RESUMO

Skeletal toxicity has been reported following exposure to polychlorinated biphenyl (PCB) mixtures. However, molecular mechanisms remain poorly understood. We exposed groups of male 4-5-week-old Sprague-Dawley rats to 3,3', 4, 4', 5-pentachlorobiphenyl (PCB 126), a dioxin-like coplanar PCB congener by a single i.p. injection of 5 µmol/kg in soy oil vehicle or vehicle alone. After 4 weeks, rats were euthanized. PCB exposure resulted in hypocalcemia (P < 0.05) and significant increases in serum PTH without changes in serum phosphorous. Hyperparathyroidism was accompanied by increased expression of mRNAs of vitamin D3 metabolizing cytochrome P450 enzymes CYP27B1 and CYP24 in the kidney (P < 0.05). PCB exposure also reduced body weight, serum IGF-1, and hepatic expression of mRNAs encoding the male-specific GH-pattern-regulated CYP2C11 and CYP3A2 relative to controls (P < 0.05). PCB exposure reduced long bone length, diameter, and surface area, but increased trabecular thickness and volume (P < 0.05). Serum osteocalcin (P < 0.05), a marker and a regulator of bone formation, was reduced, but PCB exposure had no effect on the bone resorption marker RatLaps. Exposure of human intestinal Caco-2 cells to 10-100 nM PCB 126 in the presence of vitamin D3 resulted in inhibition of mRNAs for the calcium transporters TRPV6 and PMCA1b (P < 0.05). In addition, PCB 126 suppressed osteoblastogenesis in primary bone marrow mesenchymal stem cell cultures which was blunted by the AhR antagonist CH-223191. These data provide novel evidence that skeletal toxicity after exposure to PCB 126 is a result of disruption of calcium homeostasis and the GH-IGF-1 axis, and involves direct AhR-mediated effects on bone formation.


Assuntos
Cálcio/metabolismo , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Animais , Biomarcadores/metabolismo , Células CACO-2 , Disruptores Endócrinos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Glucuronidase/metabolismo , Hormônio do Crescimento/metabolismo , Homeostase/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Klotho , Masculino , Ratos Sprague-Dawley , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/crescimento & desenvolvimento , beta Catenina/metabolismo
14.
Hum Mutat ; 40(10): 1676-1683, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31299140

RESUMO

A subset of a larger and heterogeneous class of disorders, the congenital myasthenic syndromes (CMS) are caused by pathogenic variants in genes encoding proteins that support the integrity and function of the neuromuscular junction (NMJ). A central component of the NMJ is the sodium-dependent high-affinity choline transporter 1 (CHT1), a solute carrier protein (gene symbol SLC5A7), responsible for the reuptake of choline into nerve termini has recently been implicated as one of several autosomal recessive causes of CMS. We report the identification and functional characterization of a novel pathogenic variant in SLC5A7, c.788C>T (p.Ser263Phe) in an El Salvadorian family with a lethal form of a congenital myasthenic syndrome characterized by fetal akinesia. This study expands the clinical phenotype and insight into a form of fetal akinesia related to CHT1 defects and proposes a genotype-phenotype correlation for the lethal form of SLC5A7-related disorder with potential implications for genetic counseling.


Assuntos
Alelos , Substituição de Aminoácidos , Genes Letais , Mutação , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/genética , Fenótipo , Simportadores/genética , Consanguinidade , El Salvador , Evolução Fatal , Feminino , Expressão Gênica , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Linhagem , Domínios Proteicos , Simportadores/química , Simportadores/metabolismo
15.
Alcohol Clin Exp Res ; 43(11): 2374-2383, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31483873

RESUMO

BACKGROUND: HIV infection is now largely a chronic condition as a result of the success of antiretroviral therapy. However, several comorbidities have emerged in people living with HIV (PLWH), including alcohol use disorders and musculoskeletal disorders. Alcohol use has been associated with lower bone mineral density, alterations to circulating bone turnover markers, and hypocalcemia. The pathophysiological basis of bone loss in the PLWH population is unclear but has been suggested to be linked to oxidative stress and inflammation. To test the hypothesis that PLWH consuming excessive alcohol have altered markers of bone turnover and/or calcium homeostasis in association with oxidative stress, we correlated measurements of alcohol consumption with markers of oxidative stress and inflammation, serum calcium concentrations, and measurements of bone turnover, including c-terminal telopeptide cross-links (CTX-1) and osteocalcin. METHODS: Data were drawn from cross-sectional baseline data from the ongoing New Orleans Alcohol Use in HIV (NOAH) study, comprised of 365 in care PLWH. Alcohol consumption measures (Alcohol Use Disorders Test, 30-day timeline follow-back calendar, and phosphatidylethanol [PEth]) were measured in a subcohort of 40 subjects selected based on highest and lowest PEth measurements. Multivariate linear regression was performed to test the relationships between alcohol consumption and systemic oxidative stress (4-hydroxynonenal; 4-HNE) and inflammation (c-reactive protein; CRP). RESULTS: Serum calcium and CTX-1 did not differ significantly between the high and low-PEth groups. Individuals in the high-PEth group had significantly lower serum osteocalcin (median low-PEth group: 13.42 ng/ml, inter-quartile range [IQR] 9.26 to 14.99 ng/ml; median high-PEth group 7.39 ng/ml, IQR 5.02 to 11.25 ng/ml; p = 0.0005, Wilcoxon rank-sum test). Osteocalcin negatively correlated with PEth (Spearman r = -0.45, p = 0.05) and self-reported measures after adjusting for covariates. Alcohol consumption showed mild, but significant, positive associations with serum 4-HNE, but not with CRP. Osteocalcin did not correlate with either 4-HNE or CRP. CONCLUSIONS: In this subcohort of PLWH, we detected significant associations between at-risk alcohol use and osteocalcin, and at-risk alcohol use and serum 4-HNE, suggesting suppression of bone formation independent of increased systemic oxidative stress with increasing alcohol consumption.


Assuntos
Alcoolismo/complicações , Infecções por HIV/complicações , Inflamação/complicações , Osteocalcina/deficiência , Estresse Oxidativo , Alcoolismo/sangue , Alcoolismo/metabolismo , Cálcio/sangue , Cálcio/metabolismo , Estudos Transversais , Feminino , Glicerofosfolipídeos/sangue , Infecções por HIV/sangue , Infecções por HIV/metabolismo , Humanos , Inflamação/sangue , Inflamação/metabolismo , Masculino , Nova Orleans , Osteocalcina/sangue , Estresse Oxidativo/efeitos dos fármacos
16.
Environ Health ; 18(1): 45, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072366

RESUMO

BACKGROUND: Humans are exposed to a complex mixture of environmental chemicals that impact bone and metabolic health, and traditional exposure assessments struggle to capture these exposure scenarios. Peroxisome proliferator activated receptor-gamma (PPARγ) is an essential regulator of metabolic and bone homeostasis, and its inappropriate activation by environmental chemicals can set the stage for adverse health effects. Here, we present the development of the Serum PPARγ Activity Assay (SPAA), a simple and cost-effective method to measure total ligand activity in small volumes of serum. METHODS: First, we determined essential components of the bioassay. Cos-7 cells were transfected with combinations of expression vectors for human PPARγ and RXRα, the obligate DNA-binding partner of PPARγ, along with PPRE (DR1)-driven luciferase and control eGFP reporter constructs. Transfected cells were treated with rosiglitazone, a synthetic PPARγ ligand and/or LG100268, a synthetic RXR ligand, to characterize the dose response and determine the simplest and most efficacious format. Following optimization of the bioassay, we assessed the cumulative activation of PPARγ by ligands in serum from mice treated with a PPARγ ligand and commercial human serum samples. RESULTS: Cos-7 cells endogenously express sufficient RXR to support efficacious activation of transfected PPARγ. Co-transfection of an RXR expression vector with the PPARγ expression vector did not increase PPRE transcriptional activity induced by rosiglitazone. Treatment with an RXR ligand marginally increased PPRE transcriptional activity in the presence of transfected PPARγ, and co-treatment with an RXR ligand reduced rosiglitazone-induced PPRE transcriptional activity. Therefore, the final bioassay protocol consists of transfecting Cos-7 cells with a PPARγ expression vector along with the reporter vectors, applying rosiglitazone standards and/or 10 µL of serum, and measuring luminescence and fluorescence after a 24 h incubation. Sera from mice dosed with rosiglitazone induced PPRE transcriptional activity in the SPAA in a dose-dependent and PPARγ-dependent manner. Additionally, human serum from commercial sources induced a range of PPRE transcriptional activities in a PPARγ-dependent manner, demonstrating the ability of the bioassay to detect potentially low levels of ligands. CONCLUSIONS: The SPAA can reliably measure total PPRE transcriptional activity in small volumes of serum. This system provides a sensitive, straightforward assay that can be reproduced in any cell culture laboratory.


Assuntos
Saúde Ambiental/métodos , PPAR gama/sangue , Animais , Células COS , Chlorocebus aethiops , Ligantes
17.
J Cell Physiol ; 233(9): 7007-7021, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29380368

RESUMO

The retinoid X receptors (RXR), peroxisome proliferator activated receptor gamma (PPARγ), and liver X receptors (LXR) all have been shown to regulate bone homeostasis. Tributyltin (TBT) is an environmental contaminant that is a dual RXRα/ß and PPARγ agonist. TBT induces RXR, PPARγ, and LXR-mediated gene transcription and suppresses osteoblast differentiation in vitro. Bone marrow multipotent mesenchymal stromal cells derived from female C57BL/6J mice were more sensitive to suppression of osteogenesis by TBT than those derived from male mice. In vivo, oral gavage of 12 week old female, C57Bl/6J mice with 10 mg/kg TBT for 10 weeks resulted in femurs with a smaller cross-sectional area and thinner cortex. Surprisingly, TBT induced significant increases in trabecular thickness, number, and bone volume fraction. TBT treatment did not change the Rankl:Opg RNA ratio in whole bone, and histological analyses showed that osteoclasts in the trabecular space were minimally reduced. In contrast, expression of cardiotrophin-1, an osteoblastogenic cytokine secreted by osteoclasts, increased. In primary bone marrow macrophage cultures, TBT marginally inhibited the number of osteoclasts that differentiated, in spite of significantly suppressing expression of osteoclast markers Nfatc1, Acp5, and Ctsk and resorptive activity. TBT induced expression of RXR- and LXR-dependent genes in whole bone and in vitro osteoclast cultures. However, only an RXR antagonist, but not an LXR antagonist, significantly inhibited TBTs ability to suppress osteoclast differentiation. These results suggest that TBT has distinct effects on cortical versus trabecular bone, likely resulting from independent effects on osteoblast and osteoclast differentiation that are mediated through RXR.


Assuntos
Osso Esponjoso/efeitos dos fármacos , Osso Cortical/efeitos dos fármacos , Compostos de Trialquitina/farmacologia , Animais , Calcificação Fisiológica/efeitos dos fármacos , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Proteínas da Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Receptores X do Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , PPAR gama/metabolismo , Receptores X de Retinoides/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Emerg Infect Dis ; 24(9): 1626-1632, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30124194

RESUMO

Zika and associated microcephaly among newborns were reported in Brazil during 2015. Zika has since spread across the Americas, and travel-associated cases were reported throughout the United States. We reviewed travel-associated Zika cases in California to assess the potential threat of local Zika virus transmission, given the regional spread of Aedes aegypti and Ae. albopictus mosquitoes. During November 2015-September 2017, a total of 588 travel-associated Zika cases were reported in California, including 139 infections in pregnant women, 10 congenital infections, and 8 sexually transmitted infections. Most case-patients reported travel to Mexico and Central America, and many returned during a period when they could have been viremic. By September 2017, Ae. aegypti mosquitoes had spread to 124 locations in California, and Ae. albopictus mosquitoes had spread to 53 locations. Continued human and mosquito surveillance and public health education are valuable tools in preventing and detecting Zika virus infections and local transmission in California.


Assuntos
Aedes , Surtos de Doenças/prevenção & controle , Insetos Vetores , Viagem , Infecção por Zika virus/epidemiologia , Zika virus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , California/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Gravidez , Adulto Jovem , Infecção por Zika virus/transmissão
19.
J Pharmacol Exp Ther ; 366(1): 46-57, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29653963

RESUMO

Chronic alcohol consumption increases bone resorption and decreases bone formation. A major component of ethanol (EtOH) pathology in bone is the generation of excess reactive oxygen species (ROS). The ROS-generating NADPH oxidase-4 (NOX4) is proposed to drive much of the EtOH-induced suppression of bone formation. Here, 13-week-old male wild-type (WT) and NOX4-/- mice were pair fed (PF) a high-fat (35%), Lieber-DeCarli liquid diet with or without EtOH at 30% of their total calories for 12 weeks. Micro-computed tomography analysis demonstrated significant decreases in trabecular bone volume/total volume (BV/TV) percentage and cortical thickness in WT, EtOH-fed mice compared with PF controls. EtOH-fed NOX4-/- mice also displayed decreased trabecular BV/TV and trabecular number compared with PF (P < 0.05). However, NOX4-/- mice were protected against EtOH-induced decreases in cortical thickness (P < 0.05) and decreases in collagen1 and osteocalcin mRNA expression in cortical bone (P < 0.05). In WT and NOX4-/- vertebral bone, EtOH suppressed expression of Wnt signaling components that promote osteoblast maturation. A role for NOX4 in EtOH inhibition of osteoblast differentiation was further demonstrated by protection against EtOH inhibition of osteoblastogenesis in ex vivo bone marrow cultures from NOX4-/-, but not p47phox-/- mice lacking active NADPH oxidase-2. However, bone marrow cultures from NOX4-/- mice formed fewer osteoblastic colonies compared with WT cultures (P < 0.05), suggesting a role for NOX4 in the maintenance of mesenchymal progenitor cell populations. These data suggest that NOX4 deletion is partially protective against EtOH effects on osteoblast differentiation, but may predispose bone to osteogenic impairments.


Assuntos
Osso Esponjoso/citologia , Deleção de Genes , NADPH Oxidase 4/deficiência , NADPH Oxidase 4/genética , Osteoblastos/citologia , Animais , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/efeitos dos fármacos , Osso Esponjoso/fisiologia , Etanol/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Microtomografia por Raio-X
20.
Sex Transm Dis ; 45(7): 435-441, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29465666

RESUMO

BACKGROUND: Congenital syphilis (CS), the transmission of Treponema pallidum from mother to fetus during pregnancy, can cause adverse birth outcomes. In 2012 to 2014, the CS rate in California increased more than 200% from 6.6 to 20.3 cases per 100,000 live births. Our objectives were to identify characteristics associated with delivering an infant with CS and missed opportunities for prevention among syphilis-infected pregnant women in California. METHODS: We linked California Department of Public Health syphilis surveillance records from women aged 15 to 45 years-diagnosed from March 13, 2012, to December 31, 2014-to birth records. We compared characteristics among mothers who delivered an infant with CS (CS mothers) with mothers who delivered an infant without CS (non-CS mothers) by using χ or Fisher exact tests. To visualize gaps in prevention among syphilis-infected pregnant women, we constructed a CS prevention cascade, a figure that shows steps to prevent CS. RESULTS: During the selected period, 2498 women were diagnosed as having syphilis, and 427 (17%) linked to birth records; 164 (38%) were defined as CS mothers and 263 (62%) as non-CS mothers. Mothers with CS were more likely than non-CS mothers to have their first prenatal care visit in the third trimester. High proportions of mothers in both groups reported high-risk sexual behaviors, methamphetamine use, or incarceration (13%-29%). The CS prevention cascade showed decrements of 5% to 11% in prenatal care receipt, testing, and treatment steps; only 62% of potential CS births were prevented. CONCLUSIONS: Multifaceted efforts are needed to address gaps in the CS prevention cascade and reduce CS cases in California.


Assuntos
Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mães , Sífilis Congênita/epidemiologia , Sífilis Congênita/prevenção & controle , Sífilis/diagnóstico , Adolescente , Adulto , California/epidemiologia , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Prontuários Médicos , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/microbiologia , Cuidado Pré-Natal/estatística & dados numéricos , Diagnóstico Pré-Natal/estatística & dados numéricos , Saúde Pública , Sífilis/epidemiologia , Treponema pallidum , Adulto Jovem
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