TRAPPC11-CDG muscular dystrophy: Review of 54 cases including a novel patient.

The trafficking protein particle (TRAPP) complex is a multisubunit protein complex that functions as a tethering factor involved in intracellular trafficking. TRAPPC11, a crucial subunit of this complex, is associated with pathogenic variants that cause a spectrum of disease, which can range from a limb girdle muscular dystrophy (LGMD) to developmental disability with muscle disease, movement disorder and global developmental delay (GDD)/intellectual disability (ID), or even a congenital muscular dystrophy (CMD). We reviewed the phenotype of all reported individuals with TRAPPC11-opathies, including an additional Mexican patient with novel compound heterozygous missense variants in TRAPPC11 (c.751 T > C and c.1058C > G), restricted to the Latino population. In these 54 patients muscular dystrophy signs are common (early onset muscle weakness, increased serum creatine kinase levels, and dystrophic changes in muscle biopsy). They present two main phenotypes, one with a slowly progressive LGMD with or without GDD/ID (n = 12), and another with systemic involvement characterized by short stature, GDD/ID, microcephaly, hypotonia, poor speech, seizures, cerebral atrophy, cerebellar abnormalities, movement disorder, scoliosis, liver disease, and cataracts (n = 42). In 6 of them CMD was identified. Obstructive hydrocephaly, retrocerebellar cyst, and talipes equinovarus found in the individual reported here has not been described in TRAPPC11 deficiency. As in previous patients, membrane trafficking assays in our patient showed defective abnormal endoplasmic reticulum-Golgi transport as well as decreased expression of LAMP2, and ICAM-1 glycoproteins. This supports previous statements that TRAPPC11-opathies are in fact a congenital disorder of glycosylation (CDG) with muscular dystrophy.

Clinical insights from an unusual Turner syndrome manifestation: Congenital cutis verticis gyrata.

Cutis verticis gyrata (CVG) is classified as primary or secondary according to the absence or presence of underlying soft tissue abnormalities. We report an infant with Turner syndrome (TS) who in addition presented with CVG on the scalp. The skin biopsy revealed a hamartoma-like lesion. We reviewed the clinical and histopathological findings of the 13 reported cases of congenital CVG in patients with TS, including ours. In 11 of them, CVG was localized on the skin of the scalp, mainly on the parietal region, and in two, on the forehead. Clinically, CVG had a flesh-colored aspect, with absent or sparse hair, and was not progressive. CVG was classified as primary in four patients who had skin biopsy and it was attributed to the intrauterine lymphedema of TS. However, histopathology in two of these patients identified dermal hamartoma as a secondary cause of CVG, and in three others, including ours, there were hamartomatous changes. Although further studies are required, previous findings support the proposal that some CVG may instead be dermal hamartomas. This report alerts clinicians to recognize CVG as a low-frequency manifestation of TS, but also to consider the possible co-occurrence of TS in all female infants with CVG.

Aneurysms involving the coronary arteries in a neonate with neurofibromatosis 1.

Aneurysmal coronary artery disease (ACAD) has been reported rarely in patients with neurofibromatosis type 1 (NF1), mostly in adults. We report on a female newborn affected by NF1 with ACAD disclosed during investigation for an abnormal prenatal ultrasound along with a review of the previously reported cases. The proposita had multiple café-au-lait spots and had no cardiac symptoms. Echocardiography, and cardiac computed tomography angiography confirmed aneurysms on the left coronary artery, left anterior descending coronary artery, and of the sinus of Valsalva. Molecular analysis detected the pathogenic variant NM_001042492.3(NF1):c.3943C>T (p.Gln1315*). Literature findings on ACAD in NF1 indicated that this mostly occurs in males, showing predilection for the development of aneurysms at the left anterior descending coronary artery, and manifesting predominantly as acute myocardial infarction, inclusively in teenagers, though it may be also asymptomatic as in our case. This report documents the first case of ACAD in a patient with NF1 diagnosed at birth, emphasizing that its early diagnosis is essential to prevent potential life-threatening events attributable directly to coronary lesions.

Genotyping of dengue virus from infected tissue samples embedded in paraffin.

Dengue has become one of the vector-borne diseases that affect humans worldwide. In Latin American countries, Colombia is historically one of the most affected by epidemics of this flavivirus. The underreporting of signs and symptoms of probable cases of dengue, the lack of characterization of the serotypes of the infection, and the few detailed studies of postmortem necropsies of patients are among other conditions that have delayed progress in the knowledge of the pathogenesis of the disease. This study presents the results of fragment sequencing assays on paraffin-embedded tissue samples from fatal DENV cases during the 2010 epidemic in Colombia. We found that the predominant serotype was DENV-2, with the Asian/American genotype of lineages 1 and 2. This work is one of the few reports of the circulating genotypes of dengue during the 2010 epidemic in Colombia, one of the most lethal dates in the country's history.

Chronic kidney disease: the missing concept in the 2019 EULAR/ERA-EDTA recommendations for lupus nephritis.

Chronic kidney disease (CKD) is diagnosed when glomerular filtration rate (GFR) falls below 60 ml/min/1.73 m2 or urinary albumin:creatinine ratio (UACR) reaches ≥30 mg/g, as these two thresholds indicate a higher risk of adverse health outcomes, including cardiovascular mortality. CKD is classified as mild, moderate or severe, based on GFR and UACR values, and the latter two classifications convey a high or very high cardiovascular risk, respectively. Additionally, CKD can be diagnosed based on abnormalities detected by histology or imaging. Lupus nephritis (LN) is a cause of CKD. Despite the high cardiovascular mortality of patients with LN, neither albuminuria nor CKD are discussed in the 2019 European League Against Rheumatism (EULAR)/European Renal Association-European Dialysis and Transplant Association recommendations for the management of LN or the more recent 2022 EULAR recommendations for cardiovascular risk management in rheumatic and musculoskeletal diseases. Indeed, the proteinuria target values discussed in the recommendations may be present in patients with severe CKD and a very high cardiovascular risk who may benefit from guidance detailed in the 2021 European Society of Cardiology guidelines on cardiovascular disease prevention in clinical practice. We propose that the recommendations should move from a conceptual framework of LN as an entity separate from CKD to a framework in which LN is considered a cause of CKD and evidence generated from large CKD trials applies unless demonstrated otherwise.

5'/3' RACE method for sequencing the 5' and 3' untranslated regions of Zika virus.

The spread of Zika virus (ZIKV) from the African continent to the Americas promoted its molecular evolution, as reflected by mutations in its RNA genome. Most of the ZIKV genome sequences in the GenBank database have incomplete 5' and 3' UTR sequences, reflecting the deficiency of whole-genome sequencing technologies to resolve the sequences of the genome ends. We modified a protocol for rapid amplification of cDNA ends (RACE) to determine the complete sequences of the 5' and 3' UTRs of a previously reported ZIKV isolate (GenBank no. MH544701.1). This strategy is useful for determining 5' and 3' UTR sequences of ZIKV isolates and will be useful for comparative genomics applications.

Mental fatigue changes from regular season to play-offs in semiprofessional soccer: A comparison by training days.

The main purpose was to compare by each training the mental load and fatigue reported by semiprofessional soccer players comparing between regular season phase and the play-offs. Fifty-three players (Mage  = 24.59 years) for two teams participated during the 2020/21 season. Mental load was measured with a Likert questionnaire. Mental fatigue was quantified with a Visual Analogue Scale. Four trainings were recorded each week (Monday = MD+1, Wednesday = MD-4, Thursday = MD-3 and Saturday = MD-1), with a competitive match on Sunday across 10 weeks (five dates of regular season - five dates of play-offs). A Linear Mixed Model was performed with R-studio, using the training days and the competitive phase as independent variables. The influence of time played as co-variable was also checked. Results showed MD+1 as the more mentally fatiguing day in both phases, although MD-4 were the training with higher mental load reported (p = 0.001). Comparing phases, mental fatigue was significantly higher during the play-offs (p = 0.037). With regard time played, players that did not usually play showed a decrease in mental load during the play-offs. Then, we recommend coaches to use recovery strategies for mental fatigue, avoid mentally fatiguing tasks close to competition and considerer the time played as a factor which may contribute to individual differences in player mental fatigue.

Usefulness of the MS-MLPA technique in the diagnosis of Beckwith-Wiedemann syndrome and Silver-Russell syndrome.

INTRODUCTION: Epigenetic and genomic imprinting alterations of the 11p15.5 region cause excessive or deficient growth, which result in Beckwith-Wiedemann syndrome (BWS) or Silver-Russell syndrome (SRS), respectively. OBJECTIVE: To evaluate the methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) methylation analysis technique in the diagnosis of BWS and SRS. METHODS: 11p15.5 methylation and variants were evaluated in patients with clinical diagnosis of BWS and SRS using the MS-MLPA technique in peripheral blood DNA. RESULTS: Paternal uniparental disomy and loss of maternal IC2 methylation were identified in two patients with BWS who had omphalocele and macroglossia, respectively. Paternal IC1hypomethylation was recorded in two patients with SRS of classic phenotype. CONCLUSIONS: Adequate genotype-phenotype correlation was observed with the methylation defects that were identified, which confirms the usefulness of MLPA as a first-line study in patients diagnosed with BWS and SRS.

INTRODUCCIÓN: Las alteraciones epigenéticas y genómicas de la región improntada 11p15.5 producen crecimiento excesivo o deficiente, que se manifiesta como síndrome de Beckwith-Wiedemann o síndrome de Silver-Russell, respectivamente. OBJETIVO: Evaluar la técnica de análisis de metilación MLPA (MS-MLPA, methylation-specific multiplex ligation-dependent probe amplification) en el diagnóstico de los síndromes de Beckwith-Wiedemann y de Silver-Russell. MÉTODOS: Se evaluó la metilación y las variantes de 11p15.5 en pacientes con diagnóstico clínico de síndrome de Beckwith-Wiedemann y síndrome de Silver-Russell mediante la técnica MS-MLPA en ADN de sangre periférica. RESULTADOS: Se identificó disomía uniparental paterna y pérdida de metilación del IC2 materno en dos pacientes con síndrome de Beckwith-Wiedemann, quienes presentaron onfalocele y macroglosia, respectivamente. Se registró hipometilación paterna del IC1 en dos pacientes con síndrome de Silver-Russell de fenotipo clásico. CONCLUSIONES: Se observó adecuada correlación genotipo-fenotipo con los defectos de metilación encontrados, lo que confirma la utilidad del MLPA como estudio de primera línea en pacientes con diagnóstico de síndrome de Beckwith-Wiedemann y síndrome de Silver-Russell.

The STARMEN trial indicates that alternating treatment with corticosteroids and cyclophosphamide is superior to sequential treatment with tacrolimus and rituximab in primary membranous nephropathy.

A cyclical corticosteroid-cyclophosphamide regimen is recommended for patients with primary membranous nephropathy at high risk of progression. We hypothesized that sequential therapy with tacrolimus and rituximab is superior to cyclical alternating treatment with corticosteroids and cyclophosphamide in inducing persistent remission in these patients. This was tested in a randomized, open-label controlled trial of 86 patients with primary membranous nephropathy and persistent nephrotic syndrome after six-months observation and assigned 43 each to receive six-month cyclical treatment with corticosteroid and cyclophosphamide or sequential treatment with tacrolimus (full-dose for six months and tapering for another three months) and rituximab (one gram at month six). The primary outcome was complete or partial remission of nephrotic syndrome at 24 months. This composite outcome occurred in 36 patients (83.7%) in the corticosteroid-cyclophosphamide group and in 25 patients (58.1%) in the tacrolimus-rituximab group (relative risk 1.44; 95% confidence interval 1.08 to 1.92). Complete remission at 24 months occurred in 26 patients (60%) in the corticosteroid-cyclophosphamide group and in 11 patients (26%) in the tacrolimus-rituximab group (2.36; 1.34 to 4.16). Anti-PLA2R titers showed a significant decrease in both groups but the proportion of anti-PLA2R-positive patients who achieved immunological response (depletion of anti-PLA2R antibodies) was significantly higher at three and six months in the corticosteroid-cyclophosphamide group (77% and 92%, respectively), as compared to the tacrolimus-rituximab group (45% and 70%, respectively). Relapses occurred in one patient in the corticosteroid-cyclophosphamide group, and three patients in the tacrolimus-rituximab group. Serious adverse events were similar in both groups. Thus, treatment with corticosteroid-cyclophosphamide induced remission in a significantly greater number of patients with primary membranous nephropathy than tacrolimus-rituximab.

Distribution and Chemical Composition of Lignin in Secondary Xylem of Cactaceae.

Cactaceae family has heterogeneity in the accumulation of lignocellulose due to the diversity of shapes and anatomy of the wood. Most studies focus on fibrous and dimorphic species; but the non-fibrous species are poorly studied. The aims of this work were to analyze the syringyl/guaiacyl ratio of lignin and its distribution in secondary xylem, especially in non-fibrous species. The syringyl/guaiacyl (S/G) ratio was quantified from 34 species of cacti by nitrobenzene oxidation of free-extractive wood. The distribution of lignocellulose in wood sections stained with safranin O/fast green was determined with epifluorescence microscopy. The S/G ratio was heterogeneous; most of the non-fibrous species had a higher percentage of syringyl, while the fibrous ones accumulate guaiacyl. Fluorescence emission showed that vessel elements and wide-band tracheids had similar tonalities. It is hypothesized that the presence of a higher percentage of syringyl in most cacti is part of the defense mechanism against pathogens, which together with the succulence of the stem represent adaptations that contribute to survival in their hostile environments.

Family history of thyroid disease and risk of congenital hypothyroidism in neonates with Down síndrome.

INTRODUCTION: Family history of thyroid disease (FHTD) constitutes a possible risk factor for congenital hypothyroidism (CH) in the general population; however, FHTD possible relationship with CH in subjects with Down syndrome (DS) has not yet been explored. OBJECTIVE: To determine whether FHTD is associated with an increased incidence of CH in neonates with DS. METHOD: Hospital-based case-control study in 220 neonates with DS. Thyroid function tests of 37 infants with DS and positive FHTD (cases) were compared with those of 183 newborns with DS without FHTD (control group). Data were analyzed using multivariate logistic regression analysis and adjusted odds ratios (aORs) with their respective 95 % confidence intervals (CI) were calculated. RESULTS: Nine newborns with DS in our sample had CH (4.1 %). In the multivariate analysis, FHTD showed an association with CH in neonates with DS (aOR = 8.3, 95 % CI: 2.0-34.3), particularly in males (aOR = 9.0, 95 % CI: 1.6-49.6). In contrast, newborns with DS without FHTD were less likely to suffer from CH (aOR = 0.4, 95 % CI: 0.1-0.8). CONCLUSIONS: Newborns with DS and FHTD have an eight-fold higher risk for CH, particularly when the index case is male. FHTD detailed evaluation can be an easy and accessible strategy to identify those newborns with DS at higher risk for CH.

INTRODUCCIÓN: La historia familiar de enfermedad tiroidea (HFET) como factor de riesgo para hipotiroidismo congénito (HC), en síndrome de Down (SD) aún no ha sido explorada. OBJETIVO: Determinar si la HFET está asociada a mayor riesgo de HC en neonatos con SD. MÉTODO: Estudio de casos y controles en 220 neonatos con SD. Se compararon las pruebas de función tiroidea (PFT) de 37 con SD e HFET (casos), frente a las PFT de 183 recién nacidos con SD sin HFET (grupo de referencia). Se realizó análisis de regresión logística multivariante y se calculó la razón de momios (RM) y sus respectivos intervalos de confianza del 95 % (IC 95 %). RESULTADOS: Nueve casos HC (4.1 %). El HC mostró asociación con la HFET (RMa = 8.3, IC 95 %: 2.0-34.3), particularmente en los varones (RMa = 9.0, IC 95 %: 1.6-49.6). La ausencia de HFET tuvo una RM de protección para HC (RMa = 0.4, IC 95 %: 0.1-0.8). CONCLUSIONES: La HFET puede es una estrategia fácil y accesible para identificar pacientes con SD con mayor riesgo de HC.

Complete blood count differences in a cohort of Down syndrome neonates with transient abnormal myelopoiesis screened for GATA1 pathogenic variants.

Transient abnormal myelopoiesis (TAM) raises the risk for acute myeloid leukemia of Down syndrome (DS) (ML-DS), and both are related to GATA1 pathogenic variants. Here, we analyzed which findings on complete blood count (CBC) are associated with TAM in a cohort of neonates with DS screened for GATA1 pathogenic variants. The CBCs were compared among 70 newborns with DS, including 16 patients (22.9%) with TAM (cases), and 54 patients (77.1%) without TAM (controls). TAM was defined as peripheral circulating blasts (PCBs) ≥ 1%. PCR and direct sequencing were used to screen DNA samples from peripheral blood for GATA1 exon 2 mutations. Multivariate logistic regression analyses determined that the mean count of lymphocytes was significantly higher in DS infants with TAM (p = .035) and that lymphocytosis confers a risk for TAM (adjusted odds ratio = 7.23, 95% confidence intervals: 2.02-25.92). Pathogenic variants of GATA1 were identified in 2 of 70 analyzed DS neonates (2.9%), of which one had ML-DS and another had an asymptomatic TAM. Among those DS infants with TAM, the GATA1 pathogenic variant detection was 12.5%. Our results indicated that lymphocytosis is associated with TAM in neonates with DS. However, since not all infants with an abnormal CBC had TAM, and not all infants with TAM had GATA1 pathogenic variants, we emphasize that only the search for GATA1 pathogenic variants allows the proper identification of the subgroup of DS infants with a real increasing in risk for ML-DS.

Extracranial midline defects in a patient with craniofrontonasal syndrome with a novel EFNB1 mutation.

We report a female patient with craniofrontonasal syndrome (CFNS) who in addition showed other cranial and extracranial midline defects including partial corpus callosum agenesis, ocular melanocytosis, pigmentary glaucoma, duplex collecting system, uterus didelphys, and septate vagina. She was found to have a novel pathogenic variant in exon 5 of EFNB1, c.646G>T (p.Glu216*) predicted to cause premature protein truncation. From our review, we found at least 39 published CFNS patients with extracranial midline defects, comprising congenital diaphragmatic hernia, congenital heart defects, umbilical hernia, hypospadias, and less frequently, sacrococcygeal teratomas, and internal genital anomalies in females. These findings support that the EFNB1 mutations have systemic consequences disrupting morphogenetic events at the extracranial midline. Though these are not rigorously included as midline defects, we found at least 10 CFNS patients with congenital anomalies of the kidney and urinary tract, all females. Additionally, uterus didelphys and ocular melanocytosis observed in our patient are proposed also as a previously unreported EFNB1-related midline defects. In addition, this case may be useful for considering the intentional search for genitourinary anomalies in future patients with CFNS, which will be helpful to define their frequency in this entity.

Intraoperative Findings Associated to Inpatient Mortality From Patients With Gastroschisis in Western Mexico.

BACKGROUND: Intraoperative findings during gastroschisis surgery are the main predictor associated with increased mortality. The aim of our study was to determine the type of surgical findings associated with inpatient mortality in a cohort of patients with gastroschisis from a university hospital in Western Mexico. MATERIALS AND METHODS: Infants with surgically repaired gastroschisis during the period 2011-2017 at the Dr. Juan I. Menchaca Civil Hospital of Guadalajara (Guadalajara, Mexico) were studied. Data regarding demographics, perinatal history, and intraoperative findings were collected and compared according to whether they were nonsurvivors (cases) or survivors (controls) at hospital discharge. Data were analyzed using logistic regression, determining its adjusted odds ratio (aOR) and its respective 95% confidence intervals (95% CIs). The proper adjustment of the model was verified using the Hosmer and Lemeshow test. RESULTS: Ninety-four patients with gastroschisis were studied, of which 13 were nonsurvivors (13.8%), and 81 (86.2%) were survivors at hospital discharge. In the group of survivors, primary surgical closure was performed more frequently (P = 0.018), whereas staged reduction with a silo predominated in the group of nonsurvivors (P = 0.018), and an increased frequency of complex gastroschisis (0.0001). After logistic regression analysis, intraoperative findings associated with nonsurvival were severe bowel matting (aOR: 7.3; 95% CI: 1.2-44), and prolapse of the small intestine and large intestine, plus any other organ (aOR: 15.9; 95% CI: 1.1-219.6). CONCLUSIONS: Mortality in our cohort was high (13.8%) and was significantly associated with severe bowel matting, and the prolapse of the small and large intestines, plus any other organ.

Maternal risk factors for congenital heart defects in infants with Down syndrome from Western Mexico.

Atrioventricular septal defects (AVSDs) have been identified as intriguingly infrequent among Hispanics with Down syndrome (DS) born in the United States. The aim of this study was to evaluate the effect of possible maternal risk factors in the presence of congenital heart defects (CHDs) in Mexican infants with DS. A total of 231 live birth infants born with DS during 2009-2018 at the "Dr. Juan I. Menchaca" Civil Hospital of Guadalajara (Guadalajara, Mexico) were ascertained in a case-control study. Patients with DS with any major CHD were included as cases and those without major CHD as controls. Potential risk factors were analyzed using logistic regression. Of eligible infants with DS, 100 (43.3%) had ≥1 major CHDs (cases) and were compared with a control group of 131 infants (56.7%) with DS without CHDs. Prevalent CHDs were ostium secundum atrial septal defects (ASDs) (46.9%), ventricular septal defects (27.3%), and AVSDs (14%). Lack of folic acid supplementation before pregnancy had a significant risk for CHDs in infants with DS (adjusted odds ratio [aORs] = 2.9 (95% confidence interval [95% CI]: 1.0-8.6) and in the analysis by subtype of CHDs, also, for the occurrence of ASDs (aOR = 11.5, 95% CI: 1.4-94.4). Almost half of the infants with DS in our sample had CHDs, being ASD the commonest subtype and AVSD the rarest. Our ethnic background alone or in concomitance with observed nutritional disadvantages seems to contribute differences in CHD subtype rates in our DS patients.

Prevalence and risk factors for Down syndrome: A hospital-based single-center study in Western Mexico.

Although Hispanics of Mexican origin in the United States have been identified as a population with a particularly higher rate of Down syndrome (DS), there is a paucity of studies concerning this topic in Mexico. The aim of this study was to determine the prevalence and risk factors for DS in a population from Western Mexico. For prevalence, 230 liveborn infants with DS were included from a total of 89,332 births occurring during the period 2009-2017 at the Dr. Juan I. Menchaca Civil Hospital of Guadalajara (Mexico). In order to evaluate potential DS risks, a case-control study was conducted among 633 newborns, including those 211 DS patients with full trisomy 21 (cases) and 422 infants without birth defects (controls). Data were analyzed using multivariable logistic regression analysis. The overall prevalence for DS was 25.7 per 10,000 (95% confidence interval [95% CI]: 22.4-29.1). Patients with DS had a significantly higher risk for family history of DS in distant relatives (adjusted odds ratio [aOR] = 4.4, 95% CI: 2.5-7.7), relatives with thyroid disease (aOR = 2.3, 95% CI: 1.2-4.0), maternal age ≤ 19 years (aOR = 5.1, 95% CI: 2.7-9.6) or ≥ 35 years (aOR = 3.3, 95% CI: 1.5-6.9), paternal age ≤ 19 years (aOR = 3.5, 95% CI: 1.7-7.4), pre-pregnancy BMI ≥ 25 kg/m2 (aOR = 1.6, 95% CI: 1.0-2.4), and pre-pregnancy alcohol consumption (aOR = 1.8, 95% CI: 1.1-2.9). The identified risks in family history, and previously mentioned nutritional disadvantages were associated with DS in our sample and probably also to its increased prevalence in our population.

Pfeiffer Syndrome Type 3 and Prune Belly Anomaly in a Female: Case Report and Review.

Background: Pfeiffer syndrome (PS) is an autosomal dominant entity characterized by craniosynostosis, broad thumbs, and preaxially deviated great toes. It is classified in three types depending on the severity. Type 1: Mild to moderate severity, Type 2: Severe presentation with cloverleaf skull, and Type 3: Severe craniosynostosis with prominent ocular proptosis. Association of Pfeiffer syndrome (PS) types 2 and 3 with "prune belly" anomaly has been reported in two non-related patients, one PS type 2 and one PS type 3. Case Report: we report the second case of PS type 3 in a female neonate with "prune belly" anomaly and prenatal exposure to Parvovirus B19. Conclusions: We suggest that the "prune belly" anomaly and others abdominal wall defects as omphalocele and scar-type defects may be included as a feature in PS type 2 and 3.

Apocynin combined with drugs as coadjuvant could be employed to prevent and/or treat the chronic kidney disease.

A worldwide public health problem is chronic kidney disease (CKD) presenting alarming epidemiological data. It currently affects about 10% of the adult population worldwide and has a high mortality rate. It is now known that oxidative stress represents one of the most important mechanisms in its pathophysiology, from the early stages to the terminal phase. Oxidation increases inflammation and reduces the capacity of NO• to relax vascular smooth muscle, in part by decreasing bioavailability of tetrahydrobiopterin (BH4), leading to endothelial dysfunction and high blood pressure, and due to the limited effectiveness of existing treatments, new drugs are needed to prevent and/or treat these mechanisms. The aim of this study was to test apocynin in a 5/6 nephrectomy mouse model of CKD to investigate whether its known antioxidant effect can improve the disease outcome. This effect results from the inhibition of NADPH oxidase and consequently a reduced production of the superoxide anion ([Formula: see text]). Animals were divided into five groups: sham, 5/6 nephrectomy only, and 5/6 nephrectomy followed by treatment with captopril, losartan or apocynin. The parameters evaluated were blood pressure and markers of oxidative stress ([Formula: see text]) and endothelial function (BH4). There were significantly lower levels of [Formula: see text] and a greater availability of serum BH4 in the apocynin-treated animals versus the control group and the two other drug treatments. The present findings suggest that apocynin in conjunction with a coadjuvant for modulating blood pressure may be useful for controlling the progression of CRF.