Long-term food restriction prevents ageing-associated central leptin resistance in wistar rats

AIMS/HYPOTHESIS

Ageing is associated with insulin and leptin resistance in mammals. These alterations might be caused by the increased adiposity associated with ageing, by ageing alone or both. We studied whether leptin resistance occurs at the central level in the Wistar rat and we aimed to discriminate between the effects of ageing from those of the increased adiposity associated with ageing.

METHODS

Leptin was infused intracerebroventricularly at a constant rate in young adult, old and old Wistar rats fasted for 3 months, using osmotic pumps. The effects on body weight, daily food intake, Lee index, adiposity and serum leptin values were analysed. The effect of food restriction on the expression of the long form of leptin receptor in the hypothalamus was also studied.

RESULTS

Leptin decreased daily food intake and body weight in young and old Wistar rats. With a dose of 10 microg/day similar responses were obtained in young and old rats but with a dose of 0.2 microg/day, only young rats showed decreases in these parameters. Food-restriction in old rats lowered adiposity and serum leptin to values close to those of young rats, recovered responsiveness to i.c.v. administration of leptin at the dose of 0.2 microg/day and increased leptin receptor expression in the hypothalamus.

CONCLUSION/INTERPRETATION

Our data show that old Wistar rats have a decreased response to leptin at the central level. Food-restriction recovers leptin responsiveness and increases leptin receptor in the hypothalamus suggesting that adiposity plays a key role in the development of leptin resistance associated with ageing.

Ageing increases SOCS-3 expression in rat hypothalamus: effects of food restriction

Aged Wistar rats are characterized by leptin and insulin resistance. The expression of SOCS-3 in hypothalamus increases with ageing. Food restriction during 3 months decreases obesity Lee index in aged rats with respect to their ad libitum aged-mates and brings serum leptin concentrations to values close to those of young rats. Food restriction partially reverts the increases in SOCS-3 mRNA levels associated with ageing. These results suggest that SOCS-3 may be a mediator of hypothalamic leptin resistance in the aged Wistar rat and that the hyperleptinemia associated with ageing is, at least in part, responsible for the increase of SOCS-3 expression in hypothalamus.

Decreased leptin uptake in hypothalamic nuclei with ageing in Wistar rats

Leptin interacts with specific receptors in hypothalamic nuclei and modulates energy balance. Growing evidence has shown the association of obesity and hyperleptinaemia with non-insulin-dependent diabetes mellitus and insulin resistance. The aged Wistar rat shows peripheral insulin resistance in the absence of obesity and alterations of glucose homeostasis. However, it is not known whether, in these animals, the leptin action is altered. Here we studied the effect of ageing on plasma leptin concentration and the ability of hypothalamic nuclei to capture i.c.v.-injected digoxigenin-labelled leptin. Our data indicate that 24-month-old animals are hyperleptinaemic. However, daily food intake was greater in old animals, suggesting that they are leptin resistant. Leptin uptake in the hypothalamus was reduced in old rats. This uptake was a receptor-mediated process as demonstrated by displacement. Leptin accumulation in hypothalamic nuclei was partially colocalized with neuropeptide Y fibres. Immunohistochemical and western blot analyses showed a lower amount of the long form of leptin receptors in the hypothalamus of aged rats. Analysis by RT-PCR also demonstrated a decreased expression of leptin receptor mRNA in old animals. We conclude that the lower leptin uptake may be explained, at least in part, by a decreased amount of receptors in hypothalamic neurones of the aged rats.

The impact of extrusion on the nutritional composition, dietary fiber and in vitro digestibility of gluten-free snacks based on rice, pea and carob flour blends

Consumers and the food industry are demanding healthier products. Expanded snacks with a high nutritional value were developed from different rice, pea and carob flour blends. The proximate composition, starch (total and resistant), amylose and amylopectin, dietary fiber (soluble and insoluble) contents, and the in vitro protein digestibility of different rice-legume formulations, were evaluated before and after the extrusion process. Compared with the corresponding non-extruded blends (control), the extrusion treatment did not change the total protein content, however, it reduced the soluble protein (61-86%), the fat (69-92%) and the resistant starch contents (100%). The total starch content of all studied blends increased (2-19%) after extrusion. The processing increased the in vitro protein digestibility, reaching values around 88-95% after extrusion. Total dietary fiber was reduced around 30%, and the insoluble fraction was affected to a larger extent than the soluble fraction by the extrusion process. Because of its balanced nutritional composition, high dietary fiber content, as well as low energy density, these novel gluten-free snack-like foods could be considered as functional foods and a healthier alternative to commercially available gluten-containing or gluten-free and low nutritional value snacks.

First asymmetric hetero Diels-Alder reaction of 1-sulfinyl dienes with nitroso derivatives. A new entry to the synthesis of optically pure 1,4-imino-L-ribitol derivatives

Hetero Diels-Alder (HDA) cycloaddition of chiral 1-p-tolylsulfinyl-1,3-pentadiene with benzyl nitrosoformate, under mild conditions, yields 2H-1,2-oxazine 3 with complete regioselectivity and pi-facial diastereoselectivity. Sequential osmylation and protection of the resulting glycol gives the oxazine 5 which is directly transformed into enantiomerically pure 1,4,5-trideoxy-1,4-imino-L-ribitol 8 by reduction under Pd/C.

Alternative splicing generates a novel non-secretable resistin isoform in Wistar rats1

Resistin is a secreted adipose tissue hormone that belongs to the resistin-like molecule family. We report here a new alternatively spliced isoform of the rat resistin gene, named S-resistin (short resistin), detected in adipose tissue by reverse transcription-polymerase chain reaction (RT-PCR). A comparison of this cDNA variant and genomic sequences indicates the lack of the second exon containing the secretory consensus signal. Both cDNAs, resistin and S-resistin, were carboxy-tagged with FLAG epitope and transiently expressed in cultured cell lines. While the resistin-FLAG construct gives the expected pattern for a secretion protein, the S-resistin-FLAG construct yielded a predominant nuclear staining. These results indicate that this splicing event regulates the fate and probably the function of the mature protein.

Structure and expression of the Drosophila ubiquitin-52-amino-acid fusion-protein gene

Ubiquitin belongs to a multigene family. In Drosophila two members of this family have been previously described. We report here the organization and expression of a third member, the DUb52 gene, isolated by screening a Drosophila melanogaster genomic library. This gene encodes an ubiquitin monomer fused to a 52-amino acid extension protein. There are no introns interrupting the coding sequence. Recently, it has been described that this extension encodes a ribosomal protein in Saccharomyces, Dictyostelium, and Arabidopsis. The present results show that the 5' regulatory region of DUb52 shares common features with the ribosomal protein genes of Drosophila, Xenopus and mouse, including GC- and pyrimidine-rich regions. Moreover, sequences similar to the consensus Ribo-box in Neurospora crassa have been identified. Furthermore, a sequence has been found that is similar to the binding site for the TFIIIA distal element factor from Xenopus laevis. The DUb52 gene is transcribed to a 0.9 kb mRNA that is expressed constitutively throughout development and is particularly abundant in ovaries. In addition, the DUb52 gene has been found to be preferentially transcribed in exponentially growing Drosophila cells.

Timing of p53 mutations during astrocytoma tumorigenesis

Using a combination of polymerase chain reaction and single-strand conformation polymorphism techniques (PCR-SSCP) we have analyzed 78 brain tumor samples (70 primary and 8 metastatic) for the presence of mutations in the conserved regions of the Tp53 (tumor p53) gene. We have found that only two groups, gliomas (exclusively in astrocytomas) and metastases, displayed Tp53 mutations. Three of eight (37.5%) metastases showed a mutant Tp53 allele accompanied by loss of the normal one. In contrast, the frequency of Tp53 mutations in the primary brain tumors examined was lower (5.7%). Although we have examined different types of primary brain tumors, Tp53 mutations were exclusively observed in both, low and high-grade astrocytomas (four of 24). The Tp53 mutations detected in astrocytic tumors appear to be correlated with the malignancy grade. The low-grade astrocytomas were heterozygous for the mutation, whereas the high-grade astrocytomas had affected the two Tp53 alleles, suggesting a two-steps model for inactivation of the p53 gene in astrocytomas. Thus, single p53 mutation seems to occur in initial stages of astrocytoma tumorigenesis; the later lost of the remaining wild-type allele appears associated with the progression towards a more malignant stage.

Structure and expression of the Drosophila ubiquitin-80-amino-acid fusion-protein gene

In the fruitfly Drosophila, as in all eukaryotes examined so far, some ubiquitin-coding sequences appear fused to unrelated open reading frames. Two of these fusion genes have been previously described (the homologues of UBI1-UBI2 and UBI4 in yeast), and we report here the organization and expression of a third one, the DUb80 gene (the homologue of UBI3 in yeast). This gene encodes a ubiquitin monomer fused to an 80-amino-acid extension which is homologous with the ribosomal protein encoded by the UB13 gene. The 5' regulatory region of DUb80 shares common features with another ubiquitin fusion gene, DUb52, and with the ribosomal protein genes of Drosophila, Xenopus and mouse. We also find helix-loop-helix protein-binding sequences (E-boxes). The DUb80 gene is transcribed to a 0.9 kb mRNA which is particularly abundant under conditions of high protein synthesis, such as in ovaries and exponentially growing cells.

Isolation of a structural gene mapping to subregions 63F of Drosophila melanogaster and 90B of D. hydei polytene chromosomes

We have isolated by molecular cloning techniques a structural gene that maps to subregion 63F of Drosophila melanogaster chromosome 3L. This locus being one of the early chromosomal targets for ecdysone stimulation, may be induced to puff by the hormone. The gene is on a plasmid vector and it has been designated as pDm 63F. This recombinant molecule also maps to the early ecdysone inducible subregion 90B of Drosophila hydei chromosome 4. The cytological inspection of large number of chromosomal sets after in situ hybridization of the cloned DNA, locates the cloned sequence between bands 63F 2-4 according to Bridges map. Similarly, in Drosophila hydei the cloned DNA maps between subdivisions 90B 2-4 according to Berendes' map. In situ hybridization of the pDm 63F cloned DNA, directed to the nascent RNA rather than to the DNA, shows two to three times more silver grains over the corresponding regions when puffed than in the resting stage. There are however quantitative differences attending to the transcriptional activity of homologous loci in both species. By RNA excess hybridization we have found that the cellular concentration of the 63F cloned mRNA is bout 2 times higher in hormone stimulated total larval tissues than in non-stimulated ones.

Cloning and analysis of the S2 ribosomal protein cDNA from Drosophila

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Factors Associated with Failure of Bakri Balloon Tamponade for the Management of Postpartum Haemorrhage. Case Series Study and Systematic Review

Background: Postpartum haemorrhage (PPH) is an unpredictable obstetric emergency that requires a multidisciplinary approach. Bakri balloon tamponade (BBT) is recommended when PPH does not respond to medical treatment. Nowadays few published studies have performed a multivariate analysis to determine the variables independently associated with BBT failure. Methods: Our study purpose was to determine the variables independently associated with BBT failure: first, in a large single-centre cohort study between 2010 and 2020, and second, in a systematic literature review using Medline and the Cochrane Library. Maternal and perinatal variables, PPH characteristics, technique-related variables and complications were recorded in the case series study, comparing between successful and failed BBT patients. Study characteristic and variables significantly associated with BBT failure were recorded in the systematic review. All studies used a logistic regression test. Results: The case series included 123 patients. The profile of these patients were primiparous, with vaginal delivery and a full-term new-born. BBT was successful in 81.3% of cases. Five studies were included in the systematic review, providing data from 551 patients. BBT was successful in 79.5% of cases. Conclusions: Maternal age, caesarean delivery, ≥7 red blood cells units (RBCU) transfused and curettage before BBT insertion, history of caesarean section, pre-pregnancy obesity, anteriorly placed placenta, placenta accreta, caesarean delivery, estimated blood loss before insertion of BBT, long operation duration, and coagulopathy were independent factors for BBT failure.

Workshop on Blood Loss Quantification in Obstetrics: Improving Medical Student Learning through Clinical Simulation

PURPOSE

To assess whether a clinical simulation-based obstetric blood loss quantification workshop for medical undergraduate trainees improves theoretical-practical knowledge, along with self-assurance and self-confidence.

METHODS

This was a quasi-experimental pre-post learning study conducted at the Gynaecology and Obstetrics Unit of the Hospital Gregorio Marañón, Madrid, Spain. Participants were volunteer students in their fourth year of a 6-year degree course in Medicine. The study period was divided into the stages: pre-workshop, intra-workshop, 2 weeks post-workshop and 6 months post-workshop. In the pre-workshop stage, students completed a brief online course in preparation for the workshop. The effectiveness of the workshop was assessed through multiple choice tests and self-administered questionnaires. Data were compared between time-points using statistical tests for paired samples.

RESULTS

Of the 142 students invited (age 21.94 ± 3.12 years), 138 accepted the offer of the workshop (97.2%), and 85.4% had no experience in managing blood loss. Between the stages pre- and 2 weeks post-workshop, significant improvements were observed in theoretical-practical knowledge (μ = 1.109), self-assurance and self-confidence. At the 6 months post-workshop stage, theoretical-practical knowledge diminished compared with 2 weeks post-workshop, returning to pre-workshop levels, while self-assurance and confidence failed to vary significantly in the longer term.

CONCLUSIONS

The obstetric workshop improved theoretical-practical knowledge and the self-assurance and confidence of the medical students. Results 2 weeks post-workshop were maintained up until 6 months after the training intervention. The clinical simulation-based workshop was perceived by the students as useful and necessary.

Sequences isolated from a Drosophila early-ecdysone puff are expressed in rat liver

We have studied the presence of a cloned fragment of DNA from Drosophila melanogaster in other organisms by means of nucleic acid hybridization analysis. The isolated region is localized in polytene chromosomes at the 63F subdivision. This region includes a puff that responds within minutes to ecdysone stimulation. We have found that 63F DNA from D. melanogaster hybridizes 'in situ' to both DNA and RNA from D. simulans, D. teissieri, and D. hydei. In all these species the isolated DNA remains associated with one early-ecdysone stimulated puff. The isolated Drosophila recombinant DNA is also complementary to polyadenylated RNA from foetal and adult rat liver but fails to hybridize to the nonpolyadenylated RNA classes from both sources and to polyadenylated RNA from rat mammary glands.

Maternal-Perinatal Variables in Patients with Severe Preeclampsia Who Develop Acute Kidney Injury

Introduction: At present, we are witnessing an increase in preeclampsia, especially the most severe forms, which are associated with an increased risk of maternal-perinatal morbidity and mortality. As a severity criterion, acute kidney injury (AKI) has been associated with a worse prognosis, and for this reason, the maternal and perinatal variables associated with AKI in patients with severe preeclampsia (SP) were analysed in this study. Methods: An observational, retrospective, single-centre study of patients with SP treated at a tertiary hospital between January 2007 and December 2018 was conducted. The case criteria based on the criteria established by the ACOG Practice Guidelines for Gestational Hypertension and Preeclampsia. AKI is considered when serum creatinine exceeds 1.1 mg/dL in a pregnant woman with previously normal renal function. In patients with existing chronic kidney disease (CKD), it is referred to as AKI if the baseline serum creatinine increases by 1.5 fold. Pregestational, gestational and postpartum variables were analysed up to 12 weeks postpartum using univariate and multivariate logistic regression analysis. Results: During the study period, 76,828 births were attended, and 303 pregnant women were diagnosed with SP. The annual incidence of SP increased gradually throughout the study period, reaching 1.79/100 births/year in 2018. Acute kidney injury (AKI) occurred in 24.8% of the patients. The multivariate analysis revealed an increased association with a history of previous CKD, the use of assisted reproductive techniques and caesarean section. Uric acid and thrombotic microangiopathy (TMA) had a high correlation with AKI. Indications for caesarean section are associated with AKI in SP. Regarding perinatal outcomes in cases of AKI, there was a higher percentage of neonates who required foetal lung maturation with steroids and an increased need for NICU admission. No case of maternal death was recorded; however, an increase in neonatal mortality was found among patients who did not develop AKI. After 12 weeks postpartum, 72 patients were referred to the nephrology consultation for persistent hypertension, proteinuria or renal failure. Conclusions: In preeclampsia, AKI is a common complication, especially among patients with a history of CKD, those who became pregnant using assisted reproduction techniques and those who delivered via caesarean section. The perinatal impact of AKI is mainly centred on a higher rate of NICU admission and a lower mortality rate. Among biochemical and haematological markers, the uric acid level prior to renal failure has a direct and significant correlation with the risk of AKI, as does the development of TMA in patients with preeclampsia. Therefore, the monitoring of renal function in cases of preeclampsia should be strict, and referral for a nephrology consultation may be necessary in some cases.

[Impact of an additional inspiration CT scan on the conventional protocol of the ¹⁸F-FDG PET-CT in the detection of small pulmonary nodes]

AIM

To determine the impact of an additional inspiration CT scan on the conventional ¹⁸F-FDG PET-CT protocol in the detection of small pulmonary nodules.

METHOD

One hundred consecutive patients who presented with one or various nodules were studied. Whole-body PET-CT was performed using Gemini (Philips). CT acquisition parameters were 120 kV/25 mAs, the same as those for the transmission/fusion CT (mild expiration) and inspiratory CT.

RESULTS

A total of 188 nodules were detected in the inspiratory CT with sizes between 0.3-3 cm. Non-inspiratory CT did not show 20/188 nodules (10.6%) with sizes between 0.3-1cm, this corresponding to 17 patients. The most frequent localization of non-detectable nodules in non-inspiratory CT was the lower lobes. ¹⁸F-FDG uptake was detected by the PET in 83.9% and 72% of nodules with > 1 cm and between 0.7 and 1cm, respectively. However, only 10.5% of nodules <0.7 cm showed increased metabolic activity.

CONCLUSION

In selected patients, inspiratory CT added to conventional PET-CT significantly improves the detection of small nodules (10.6%), especially in those lesions located in the lower lobes, due to respiratory movements, and may have an impact on patient management.

Effects of Sex, Age and Height on Symphysis–Ischial Spine Distance Measured on a Pelvic CT

Objective: To examine the influence of age, sex and height on the symphysis–ischial spine distance (SID) measured on pelvic Computed tomography (CT)images in subjects of reproductive age, and to determine the interobserver reproducibility. This measurement (SID) is of great importance because the use of intrapartum ultrasound is based on the assumption of a specific value (30 mm) of such a measurement. Methods: This was a cross-sectional descriptive study in which SID was measured in subjects aged 20 to 44 years who had been scheduled for pelvic CT at our centre from January 2018 to May 2021 for different reasons. Radiographic measurements of the pelvis were obtained through the multiplanar reconstruction of the CT image. The images obtained from all of the participants were independently assessed by three senior radiologists, and the SID measurements made by each one were blinded from those of the remaining observers. Correlations between the SID and patient age, height and sex were analyzed by univariate and multivariate linear regression. Results: The mean SID for 87 of the enrolled participants (45 women, 42 men) was 28.2 ± 6.25 mm. Among the observers, the mean difference in this distance was 1 to 2 mm, and was scarcely related to measurement size, with agreement being greater than 70%. The mean SID was significantly related to sex and height (SID = −24.9 − 6.51 × sex (0 or 1) + 0.34 × height (cm); p = 0.01; sex equals 1 for a man and 0 for a woman), such that it was a mean of 2.5 mm greater in women than men (29.50 mm vs. 26.99 mm). Conclusion: Measurements of SID on CT images show good interobserver reproducibility, and are related to sex and height.

[Prevalence of antibodies against hepatitis C virus in multitransfused patients]

We have done a study in order two know the prevalence of anti-hepatitis C virus antibodies in polytransfused patients with hemophilia, leukemia and hemolytic anemia, along with 17 healthy donors, without previous history of transfusions. We analyzed samples from 10 hemophilic patients and 12 from leukemia, lymphoma and hemolytic anemia, all of them had received blood or blood products, at least six months before the study. Using a second generation ELISA, 4 positive sample (3 hemophilic and 1 lymphoma) were detected (10.26%), which represent a prevalence of 30% in the hemophilic group, in contrast with the prevalence detected in other countries. A very significant statistic association was demonstrated, between the positive ELISA, the amount of the transfused product (P < 0.0004) and the type of blood product used for transfusion (crioprecipited, P = 0.000, plasma P = 0.000).

Patients with Invasive Lobular Carcinoma Show a Significant Increase in IRS-4 Expression Compared to Infiltrative Ductal Carcinoma—A Histopathological Study

Background and Objectives: Breast cancer (BC) is the first diagnosed type of cancer and the second leading cause of cancer-related mortality in women. In addition, despite the improvement in treatment and survival in these patients, the global prevalence and incidence of this cancer are rising, and its mortality may be different according to the histological subtype. Invasive lobular carcinoma (ILC) is less common but entails a poorer prognosis than infiltrative ductal carcinoma (IDC), exhibiting a different clinical and histopathological profile. Deepening study on the molecular profile of both types of cancer may be of great aid to understand the carcinogenesis and progression of BC. In this sense, the aim of the present study was to explore the histological expression of Insulin receptor substrate 4 (IRS-4), cyclooxygenase 2 (COX-2), Cyclin D1 and retinoblastoma protein 1 (Rb1) in patients with ILC and IDC. Patients and Methods: Thus, breast tissue samples from 45 patients with ILC and from 45 subjects with IDC were analyzed in our study. Results: Interestingly, we observed that IRS-4, COX-2, Rb1 and Cyclin D1 were overexpressed in patients with ILC in comparison to IDC. Conclusions: These results may indicate a differential molecular profile between both types of tumors, which may explain the clinical differences among ILC and IDC. Further studies are warranted in order to shed light onto the molecular and translational implications of these components, also aiding to develop a possible targeted therapy to improve the clinical management of these patients.

First-Trimester Ultrasound Imaging for Prenatal Assessment of the Extended Cardiovascular System Using the Cardiovascular System Sonographic Evaluation Algorithm (CASSEAL)

INTRODUCTION AND OBJECTIVES

To compare fetal images obtained at the first- and second-trimester ultrasound scan when applying the Cardiovascular System Sonographic Evaluation Algorithm (CASSEAL).

METHODS

Using the CASSEAL protocol, nine sequential axial views were acquired in B-mode and color Doppler at the first- and second-trimester ultrasound scans, visualizing the main components of the extended fetal cardiovascular system. Images were compared qualitatively between both trimesters.

RESULTS

We obtained comparable images for all the nine axial views described in the CASSEAL protocol, with few differences and limitations.

CONCLUSIONS

The CASSEAL protocol is reproducible in the first trimester, and could help in the early detection of fetal cardiovascular abnormalities. It represents a promising additional tool in order to increase the CHD detection rate.

[Diagnosis of isolated fetal aberrant right subclavian artery]

A case of a fetal isolated aberrant right subclavian artery (ARSA) diagnosis and discuss its clinical implications and the methodology used to assess the fetal right subclavian artery by transabdominal ultrasound in normal cases and those with ARSA is reported.

CLINICAL CASE

A 35-year-old pregnant woman in her twentieth week of pregnancy was evaluated at our Fetal Medicine Unit. An isolated ARSA was detected by a transabdominal ultrasound scan of the fetus. The visualization of this anomaly was achieved through an axial view of the fetal thorax, at the level of the three vessels and trachea scanning plane. It was observed that the origin of ARSA from the aortic arch was close to the ductus arteriosus and it followed a retrotracheal course towards the right arm. The described methodology used to assess the right subclavian artery could be useful for prenatal diagnosis in cases of ARSA. Based on this protocol, further studies could be performed to evaluate the utility of ARSA as a sonographic marker for chromosomal abnormality and congenital heart disease. After the diagnosis of an isolated ARSA, the performance of a fetal karyotype test is still debatable.