Low quality of maternal and child nutritional care at the primary care in Mexico: an urgent call to action for policymakers and stakeholders

BACKGROUND

Maternal and child malnutrition represents a public health problem in Mexico Primary care (PC) is responsible for introducing women and children under five to the health system, detecting diseases on time, and providing medical services, including pharmacological treatment if necessary. Providing these services with quality is essential to improve maternal and child health. This study evaluated the quality of nutritional care during preconception, pregnancy, postpartum, infancy, and preschool age at the PC health units across six Mexican states between 2020 and 2021.

METHODS

We conducted a cross-sectional study with a mixed approach in units of the Secretary of Health to assess the quality of nutritional care during preconception, pregnancy, postpartum, childhood, and preschool age. The level of quality was calculated by the percentage of compliance with 16 indicators that integrated a Quality Index of Maternal and Child Nutritional Care (ICANMI, by its Spanish acronym). Compliance by indicator, by life stage, and overall was categorized using the following cut-off points: poor quality (≤ 70%), insufficient quality (71-89%), and good quality (≥ 90%). The perceptions of the barriers and facilitators that affect maternal and child nutrition were evaluated through semi-structured interviews with health professionals (HP) and users. All qualitative instruments were developed with a gender and intercultural perspective.

RESULTS

Considering the whole sample studied, maternal and child nutritional care quality during the five life stages evaluated was bad (compliance: ≤12%), reflected in the ICANMI, which had a compliance of 8.3%. Principal barriers identified to providing high-quality nutritional care were the lack of knowledge and training of health professionals, shortages of equipment, medicine, personnel, and materials, the disappearance of the social cash transfer program Prospera, the absence of local indigenous language translators to support communication between doctor and patient, and the persistence of machismo and other practices of control over women.

CONCLUSIONS

These findings underscore the need for initiatives to improve the quality of nutritional care in PC facilities across Chihuahua, State of Mexico, Veracruz, Oaxaca, Chiapas, and Yucatan. It is necessary for government and health authorities, along with various stakeholders, to collaboratively devise, implement, and assess intercultural and gender-oriented policies and programs geared towards ensuring the health infrastructure and enhancing the training of health professionals to diagnose and treat the prevalence and occurrence of diverse forms of malnutrition in both maternal and child populations.

Development and validation of a new set of indicators to assess the quality of maternal and child nutritional care at the primary care

Introduction

Maternal and child malnutrition is a worldwide public health problem with short, medium, and long-term adverse consequences for both mother and child. In Mexico, maternal and child malnutrition represents a serious public health problem that must be urgently addressed. In this context, Primary Health Care (PHC) plays an important role in the prevention, detection, monitoring, and treatment of the different forms of maternal and child malnutrition. Assessing the quality of nutritional care offered at this level of care is necessary in order to improve it; however, there are no indicators for the evaluation of this quality. Therefore, this study aimed at developing a set of indicators to assess the quality of maternal and child nutritional care at PHC.

Methods

We developed indicators for different stages of life: preconception, pregnancy, infancy, and preschool age. A systematic review of the literature on clinical guidelines for the prevention, diagnosis, and treatment of the different forms of malnutrition was carried out; the recommendations of the guidelines evaluated with good quality were extracted.

Results

Based on these recommendations, 22 indicators were constructed. A pilot study was carried out to validate the indicators and 16 indicators were selected to assess the maternal and child nutritional care at PHC.

Prognostic and reclassification value of serum cathepsin S over the GRACE risk score in patients with non-ST-segment elevation acute coronary syndrome

Background

Cathepsin S is an extracellular matrix degradation enzyme that plays an important role in atherosclerotic cardiovascular disease by inducing vasa vasorum development and atherosclerotic plaque rupture.

Purpose

To determine the prognostic and reclassification value of baseline serum cathepsin S after adjustment for the Global Registry of Acute Coronary Events (GRACE) score, which is a clinical guideline recommended risk score in non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Methods

Serum cathepsin S was measured by ELISA in 1,129 consecutive patients presenting with acute symptoms to the emergency department for whom a final adjudicated diagnosis of NSTE-ACS was made. All-cause mortality or all-cause death/non-fatal myocardial infarction (MI) after a median follow-up of 21 months were evaluated as the primary or secondary study endpoint, respectively. The Net Reclassification Index (NRI) estimated the reclassification predictive value for risk of each end-point of cathepsin S over the GRACE score.

Results

After a median follow-up of 21 months 101 (8.95%) deaths were reported. The combined endpoint of death or non-fatal MI occurred in 176 (15.6%) patients. Dose-response curve analysis adjusted for the effect of age, gender, diabetes mellitus, high-sensitivity-cardiac troponin T, high-sensitivity C-reactive protein, revascularization and index diagnosis revealed a non-linear association of continuous cathepsin S with all-cause death (P=0.036 for non-linearity; adjusted HR=1.60 for 80th vs. 20th percentiles, P=0.038) or with the combined endpoint (P=0.008 for non-linearity, adjusted HR=1.53 for 80th vs. 20th percentiles, P=0.011). Serum cathepsin S maintained its predictive value for all-cause death (adjusted HR=1.70 highest vs. lowest tertile, 95% CI 1.03–2.82, P=0.039) after adjusting for the GRACE Score. Similarly, cathepsin S predicted the combined endpoint of all-cause death or non-fatal MI (adjusted HR=1.67 highest vs. lowest tertile, 95% CI 1.15–2.42, P=0.007) independently of the GRACE Score. When cathepsin S was added over the GRACE Score it correctly reclassified risk for all-cause death in 20% of the population (P=0.004). Similarly, serum Cathepsin S conferred a significant reclassification value over the GRACE score for all-cause death or non-fatal MI in 15.9% of the population.

Conclusions

Serum cathepsin S is a predictor of mortality and improves risk stratification over the GRACE score in patients with NSTE-ACS. The clinical application of cathepsin S as a novel biomarker in NSTE-ACS should be further explored and validated.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): German Heart Foundation

Barriers and facilitators to breastfeeding during the immediate and one month postpartum periods, among Mexican women: a mixed methods approach

BACKGROUND

Evidence suggests that inadequate hospital practices, as well as sociocultural and community factors have detrimental effects on timely initiation as the first breastfeed within first hour after birth, and exclusive breastfeeding. The purpose of the study was to examine the factors that influence timely initiation of breastfeeding and exclusive breastfeeding at birth and 1 month postpartum in Mexican women delivering in public and private hospitals.

METHODS

Mixed methods were conducted between May and July 2017, including surveys (n = 543) and semi-structured interviews (n = 60) in the immediate (7 h) and intermediate (30 days) postpartum periods. Participants were women aged 15-49 years, in public and private hospitals, of urban and rural municipalities of Chihuahua and Puebla, Mexico.

RESULTS

Timely initiation was reported by 49.4% of mothers, and 34.7% reported that their children received infant formula at the hospital. Only 44.8% of women reported exclusive breastfeeding at 1 month postpartum. Timely initiation of breastfeeding was higher in women with vaginal delivery (62.1 vs 35.5%; p < 0.05) and those who received information during pregnancy (OR 1.07; p = 0.018). Exclusive breastfeeding at 1 month postpartum was related to older maternal age (OR 1.05; p < 0.001) and the fact that the mothers had received more information about breastfeeding during pregnancy (OR 1.13; p = 0.0001). Infant formula use was less associated with timely initiation (OR 0.46; p = 0.001). Participants in qualitative data identified the emotional, physical and economic benefits of breastfeeding, however, the perception about insufficient production of human milk, and the belief that infant formula is recommended, persists.

CONCLUSIONS

Modification of hospital practices, such as decreasing the number of cesarean and the use of infant formula, as well as the support of the initiation and continuation of exclusive breastfeeding by health personnel and family members, could help increase breastfeeding practices in Mexican women.

P4492Peripheral blood mononuclear cell expression of the stabilizing RNA-binding protein HuR is associated with incidence and extent of human atherosclerotic cardiovascular disease

Background

Human Antigen R (HuR) is a stabilizing RNA-binding protein that regulates the expression of several pro-inflammatory molecules. However, its regulation in human atherosclerotic cardiovascular disease remains unknown.

Purpose

To determine the association of peripheral blood mononuclear cell HuR expression with established markers of increased cardiovascular risk and atherosclerosis burden in patients with subclinical or clinically overt coronary artery disease (CAD).

Methods

HuR mRNA expression was measured in peripheral blood mononuclear cells derived from 289 patients with stable CAD or acute myocardial infarction (AMI) and 373 individuals without clinically overt cardiovascular disease (CVD). Structural and functional vascular measurements including intima-media thickness (IMT) and number of atheromatous plaques by carotid and femoral artery ultrasonophaphy, markers of arterial wave reflections by pulse wave analysis and pulse wave velocity were used as surrogate markers of subclinical CVD. The number of angiographically confirmed diseased coronary arteries (>50% stenosis) was used to assess the extent of CAD.

Results

HuR mRNA expression was significantly increased in patients with CAD (both stable and AMI) compared to controls (p=0.039). Subgroup analysis revealed that STEMI patients (n=107) had increased levels of HuR expression compared to NSTEMI (n=49, p=0.03). Among patients with stable CAD (n=133), high HuR expression was independently associated with the number of diseased coronary arteries (OR=1.35 for 1-SD increase in HuR, 95% CI 1.07–1.72, p=0.012), as well as with reduced ejection fraction (EF<45%, OR=1.32 per 1-SD increase, 95% CI 1.05–1.85, p=0.024). Among individuals without CVD, high HuR was associated with lower HDL levels (adjusted beta=-5.2 mg/dl for highest versus lowest quartile, p=0.03) and higher diastolic blood pressure (adjusted beta=3.6 mmHg, p=0.007), while, after adjustment for traditional cardiovascular risk factors, HuR levels in individuals without CVD were independently associated with increased IMT in the common carotid artery (mean increase 6.2% for highest versus lowest quartile, p=0.019).

Conclusion

HuR expression is associated with early subclinical arterial disease in individuals without clinically overt CVD and with the presence and severity of cardiac and vascular dysfunction in patients with clinically overt CAD. These findings imply a clinical role of the HuR pathway in cardiovascular disease and warrant further investigation.

2228Circulating serum extracellular matrix degradation enzyme cathepsin S predicts mortality and improves risk stratification over the GRACE score in patients with non-ST elevation acute coronary syndrom

Background

Blood-based biomarkers may be useful in the identification of residual risk for death or acute myocardial infarction (AMI) in patients with a previous acute coronary syndrome. Cathepsin S (CTSS) is a lysosomal cysteine protease with potent elastolytic and collagenolytic activity, which plays an important role in cardiovascular disease through extracellular matrix degradation, vasa vasorum development and atherosclerotic plaque rupture. The aim of the present study was to determine the prognostic and reclassification value of baseline circulating levels of CTSS after adjustment for the Global Registry of Acute Coronary Events (GRACE) score, which is widely recommended for risk stratification in non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Methods

CTSS was measured in blood samples collected from 1,129 consecutive patients with adjudicated NSTE-ACS presenting at an acute chest pain unit for evaluation of a possible acute coronary syndrome. Cardiovascular (CV) death and a composite of all-cause mortality and AMI were evaluated as the primary and secondary endpoints of the study, respectively. The additive prognostic value of CTSS over the GRACE score was estimated by the Net Reclassification Index (NRI) that examines the net upward and downward reclassification into correct pre-defined risk categories.

Results

After a median follow-up of 21 months, 101 (8.95%) deaths were reported, of which 63 (5.6%) were of cardiac origin. The combined endpoint occurred in 176 (15.6%) patients. Patients with CTSS in the highest tertile presented the greatest risk for all-cause mortality (HR=1.84 for highest versus lowest tertile of CTSS distribution, 95% CI 1.1–3.08, P=0.02) and CV death (HR=2.5 for highest versus lowest tertile of CTSS distribution, 95% CI 1.24–5.05, P=0.011) after adjustment for age, gender, diabetes mellitus, hs-cTnT, hsCRP, revascularization and index diagnosis. Similarly, CTSS was associated with increased risk of cardiovascular death after adjusting for the GRACE Score (adjusted HR for highest versus lowest tertile of CTSS distribution=2.34, 95% CI 1.18–4.64, P=0.015). Further, CTSS predicted the combined endpoint of all-cause death or non-fatal MI independently of the GRACE Score (adjusted HR for highest versus lowest tertile of CTSS distribution=1.67, 95% CI 1.15–2.42, P=0.007). When CTSS was added over the GRACE Score, it conferred significant reclassification value for CV death (NRI=21.4%, P=0.008). Similarly, CTSS correctly reclassified risk for all-cause death or non-fatal MI (P=0.006) in 15.9% of the population.

Conclusions

Circulating CTSS predicts mortality and improves risk stratification of patients with NSTE-ACS over the GRACE score recommended by clinical guidelines. The clinical application of CTSS as a novel biomarker in NSTE-ACS should be further explored and validated.

Close Cassini flybys of Saturn’s ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus

Saturn’s main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. Data on the moons’ morphology, structure, particle environment, and composition were returned, along with images in the ultraviolet and thermal infrared. We find that the optical properties of the moons’ surfaces are determined by two competing processes: contamination by a red material formed in Saturn’s main ring system and accretion of bright icy particles or water vapor from volcanic plumes originating on the moon Enceladus.

Aureochrome 1a is involved in the photoacclimation of the diatom Phaeodactylum tricornutum

Aureochromes constitute a family of blue light (BL) receptors which are found exclusively in heterokont algae such as diatoms (Bacillariophyceae) and yellow-green algae (Xanthophyceae). Previous studies on the diatom Phaeodactylum tricornutum indicate that the formation of a high light acclimated phenotype is mediated by the absorption of BL and that aureochromes might play an important role in this process. P. tricornutum possesses four genes encoding aureochromes. In this study we confirm the nuclear localisation of the PtAUREO1a, 1b and 2 proteins. Furthermore we studied the physiology of light quality acclimation in genetically transformed P. tricornutum cell lines with reduced expression of the aureochrome 1a gene. The results demonstrate that the AUREO1a protein has a distinct function in light acclimation. However, rather unexpectedly AUREO1a seems to repress high light acclimation which resulted in a state of ‘hyper’ high light acclimation in aureo1a silenced strains. This was indicated by characteristic changes of several photosynthetic parameters, including increased maximum photosynthesis rates, decreased chlorophyll a contents per cell and increased values of non-photochemical quenching in AUREO1a silenced strains compared to wild type cultures. Strikingly, AUREO1a silenced strains exhibited phenotypic differences compared to wild type cells during cultivation under BL as well as under red light (RL) conditions. Therefore, AUREO1a might influence the RL signalling process, suggesting an interaction of AUREO1a with RL perception pathways.

Design of an implantable seismic sensor placed on the ossicular chain

This paper presents a design guideline for matching a fully implantable middle ear microphone with the physiology of human hearing. The guideline defines the first natural frequency of a seismic sensor placed at the tip of the manubrium mallei with respect to the frequency-dependence hearing of the human ear as well as the deflection of the ossicular chain. A transducer designed in compliance with the guideline presented reduces the range of the output signal while preserving all information obtained by the ossicular chain. On top of a output signal compression, static deflections, which can mask the tiny motions of the ossicles, are reduced. For guideline verification, a microelectromechanical system (MEMS) based on silicon on insulator technology was produced and tested. This prototype is capable of resolving 0.4 pm/Hz with a custom made read-out circuit. For a bandwidth of 0.1 kHz, this deflection is comparable with the lower threshold of speech (≈ 40 phon).

High light acclimation in the secondary plastids containing diatom Phaeodactylum tricornutum is triggered by the redox state of the plastoquinone pool

In diatoms, the process of energy-dependent chlorophyll fluorescence quenching (qE) has an important role in photoprotection. Three components are essential for qE: (1) the light-dependent generation of a transthylakoidal proton gradient; (2) the deepoxidation of the xanthophyll diadinoxanthin (Dd) into diatoxanthin (Dt); and (3) specific nucleus-encoded antenna proteins, called Light Harvesting Complex Protein X (LHCX). We used the model diatom Phaeodactylum tricornutum to investigate the concerted light acclimation response of the qE key components LHCX, proton gradient, and xanthophyll cycle pigments (Dd+Dt) and to identify the intracellular light-responsive trigger. At high-light exposure, the up-regulation of three of the LHCX genes and the de novo synthesis of Dd+Dt led to a pronounced rise of qE. By inhibiting either the conversion of Dd to Dt or the translation of LHCX genes, qE amplification was abolished and the diatom cells suffered from stronger photoinhibition. Artificial modification of the redox state of the plastoquinone (PQ) pool via 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 5-dibromo-6-isopropyl-3-methyl-1,4-benzoquinone resulted in a disturbance of Dd+Dt synthesis in an opposite way. Moreover, we could increase the transcription of two of the four LHCX genes under low-light conditions by reducing the PQ pool using 5-dibromo-6-isopropyl-3-methyl-1,4-benzoquinone. Altogether, our results underline the central role of the redox state of the PQ pool in the light acclimation of diatoms. Additionally, they emphasize strong evidence for the existence of a plastid-to-nucleus retrograde signaling mechanism in an organism with plastids that derived from secondary endosymbiosis.

AUREOCHROME1a-mediated induction of the diatom-specific cyclin dsCYC2 controls the onset of cell division in diatoms (Phaeodactylum tricornutum)

Cell division in photosynthetic organisms is tightly regulated by light. Although the light dependency of the onset of the cell cycle has been well characterized in various phototrophs, little is known about the cellular signaling cascades connecting light perception to cell cycle activation and progression. Here, we demonstrate that diatom-specific cyclin 2 (dsCYC2) in Phaeodactylum tricornutum displays a transcriptional peak within 15 min after light exposure, long before the onset of cell division. The product of dsCYC2 binds to the cyclin-dependent kinase CDKA1 and can complement G1 cyclin-deficient yeast. Consistent with the role of dsCYC2 in controlling a G1-to-S light-dependent cell cycle checkpoint, dsCYC2 silencing decreases the rate of cell division in diatoms exposed to light-dark cycles but not to constant light. Transcriptional induction of dsCYC2 is triggered by blue light in a fluence rate-dependent manner. Consistent with this, dsCYC2 is a transcriptional target of the blue light sensor AUREOCHROME1a, which functions synergistically with the basic leucine zipper (bZIP) transcription factor bZIP10 to induce dsCYC2 transcription. The functional characterization of a cyclin whose transcription is controlled by light and whose activity connects light signaling to cell cycle progression contributes significantly to our understanding of the molecular mechanisms underlying light-dependent cell cycle onset in diatoms.

[Care of the dying in the hospital: initial experience with the Liverpool Care Pathway (LCP) in Germany]

BACKGROUND AND OBJECTIVE

In the last few years public interest in the care of severely ill and dying patients has been growing. The aim of palliative medicine is to improve the care of the dying. However, this is still not achieved in many general hospitals. The Liverpool Care Pathway (LCP) for the care of the dying intends to change this situation. The aim of this study was to explore the views of professionals using the LCP as a framework for ensuring good care of the dying.

METHODS

A qualitative study was conducted with an interdisciplinary focus group of ten professionals (nurses, physicians, spiritual adviser, social worker, physiotherapist and art therapist) to explore their views and experience after implementation of the LCP in a palliative care unit (PCU). The recorded discussion between them was transcribed verbatim and analysed using content analysis by three independent reviewers.

RESULTS

Seven nurses and three physicians with an average work experience of 16 years each took part in the focus group. Based on the experience of 24 patients, the LCP was evaluated as very positive by all participants. In particular, three aspects were emphasized as having high relevance for a good quality of care: improvement of self-confidence, better control of symptoms, and enhancement of the communication between professionals and with patients and their relatives. However, some weaknesses were also mentioned, e.g. inadequate effort of documenting the beginning of implementing the scheme.

CONCLUSION

The LCP was well received by professionals after the initial implementation of the LCP in a German PCU. The LCP was judged as an appropriate and helpful framework in the care of the dying.

Ubiquitin system-dependent regulation of growth hormone receptor signal transduction

The growth hormone (GH) receptor is a key regulator of cellular metabolism. Unlike most growth factor receptors, its downregulation is not initiated by its ligand. Like many growth factor receptors, specific molecular mechanisms guarantee that a receptor can signal only once in its lifetime. Three features render the GH receptor unique: (a) an active ubiquitination system is required for both uptake (endocytosis) and degradation in the lysosomes; (b) uptake of the receptor is a continuous process, independent of both GH binding and Jak2 signal transduction; (c) only the cell surface expression of dimerised GH receptors is controlled by the ubiquitin system. This system enables two independent regulatory mechanisms for the endocrinology of the GH/GHR axis: the pulsatile secretion of GH by the pituitary and the GH sensitivity of individual cells of the body by the effects of the ubiquitin system on GH receptor availability.

The ubiquitin-dependent endocytosis motif is required for efficient incorporation of growth hormone receptor in clathrin-coated pits, but not clathrin-coated lattices

Endocytosis of the growth hormone receptor (GHR) requires an active ubiquitin-conjugation system. In addition, it depends on a 10 amino acid residues motif in the GHR-cytoplasmic tail, the ubiquitin dependent-endocytosis or UbE-motif. To gain insight into the role of ubiquitination in the early steps of endocytosis, we performed an ultrastructural analysis of GH-uptake in Chinese hamster cells expressing wild-type or mutant GHRs. In wild-type GHR cells, GH was found to be exclusively taken up via clathrin-coated pits. In early endosomes it was efficiently sorted from recycling transferrin and targeted to the degradative pathway. Mutation of all lysine residues of a truncated GHR (GHR-399K–) precludes ubiquitination of the receptor, but internalization of GHR-399K– still depends on an active ubiquitin system. We found that GHR-399K– incorporates GH into clathrin-coated vesicles with the same efficiency as wild-type GHR. By contrast, a mutation in the UbE-motif (GHR-F327A) largely abolished incorporation of GH into clathrin-coated vesicles. Notably, access of GH to clathrin-coated lattices was not affected in GHR-F327A cells. These data corroborate and extend previous data that the UbE-motif but not ubiquitination of the receptor itself recruits GHR into clathrin-coated vesicles. Moreover, they suggest that incorporation of GHR into clathrin-coated lattices is differentially regulated from incorporation into clathrin-coated pits.

Proteasome inhibitors block a late step in lysosomal transport of selected membrane but not soluble proteins

The ubiquitin-proteasome pathway acts as a regulator of the endocytosis of selected membrane proteins. Recent evidence suggests that it may also function in the intracellular trafficking of membrane proteins. In this study, several models were used to address the role of the ubiquitin-proteasome pathway in sorting of internalized proteins to the lysosome. We found that lysosomal degradation of ligands, which remain bound to their receptors within the endocytic pathway, is blocked in the presence of specific proteasome inhibitors. In contrast, a ligand that dissociates from its receptor upon endosome acidification is degraded under the same conditions. Quantitative electron microscopy showed that neither the uptake nor the overall distribution of the endocytic marker bovine serum albumin-gold is substantially altered in the presence of a proteasome inhibitor. The data suggest that the ubiquitin-proteasome pathway is involved in an endosomal sorting step of selected membrane proteins to lysosomes, thereby providing a mechanism for regulated degradation.

Oleaceous laurophyllous leaf fossils and pollen from the European Tertiary

By using cuticular analysis for the first time laurophyllous leaf remains from the European Tertiary have been reliably identified as belonging to the Oleaceae. Despite ecologically determined variation in cuticular structures, Late Miocene leaf material from northern Italy is assigned to a single species, Oleinites liguricus Sachse n. sp. The associated oleaceous pollen grains support that this species has been a prominent component, at least locally, of a laurophyllous forest community. From extensive comparisons with leaf cuticles and pollen of extant Oleaceae it may be concluded, that the fossil leaves and probably corresponding pollen represent the tribe Oleeae and may originate from a plant closely comparable to extant Chionanthus and Fraxinus. A reinvestigation of some Oligocene laurophyllous leaf remains has uncovered two more oleaceous species in the European Tertiary: Oleinites maii (Buzek et al.) Sachse comb. nov., and Oleinites hallbaueri (Mai) Sachse comb. nov. Considering the high diversity of laurophyllous Oleaceae in modern evergreen and mixed mesophytic forests and the common presence of oleaceous pollen in the fossil record it may be expected that cuticular analysis of laurophyllous leaf fossils will lead to the recognition of an increased number of oleaceous taxa in Tertiary leaf assemblages.

Growth hormone receptor ubiquitination coincides with recruitment to clathrin-coated membrane domains

Endocytosis of the growth hormone receptor (GHR) depends on a functional ubiquitin conjugation system. A 10-amino acid residue motif within the GHR cytosolic tail (the ubiquitin-dependent endocytosis motif) is involved in both GHR ubiquitination and endocytosis. As shown previously, ubiquitination of the receptor itself is not required. In this paper ubiquitination of the GHR was used as a tool to address the question of at which stage the ubiquitin conjugation system acts in the process of GHR endocytosis. If potassium depletion was used to interfere with early stages of coated pit formation, both GHR endocytosis and ubiquitination were inhibited. Treatment of cells with methyl-beta-cyclodextrin inhibited endocytosis at the stage of coated vesicle formation. Growth hormone addition to methyl-beta-cyclodextrin-treated cells resulted in an accumulation of ubiquitinated GHR at the cell surface. Using immunoelectron microscopy, the GHR was localized in flattened clathrin-coated membranes. In addition, when clathrin-mediated endocytosis was inhibited in HeLa cells expressing a temperature-sensitive dynamin mutant, ubiquitinated GHR accumulated at the cell surface. Together, these data show that the GHR is ubiquitinated at the plasma membrane, before endocytosis occurs, and indicate that the resident time of the GHR at the cell surface is regulated by the ubiquitin conjugation system together with the endocytic machinery.

[The content of pepsinogen in the blood plasma of growing fallow deer (Dama dama L.) raised helminth free and under natural conditions in captivity]

Pepsinogen values were determined in helminth free (n = 12) and naturally raised farmed fallow deer (n = 10-12) from birth (June 1992) to 11 (May 1993) and 15 months (September 1993) of age respectively in 4 weekly intervals. At birth the plasma pepsinogen value was 0.708 +/- 0.197 U Tyrosin/l and decreased thereafter until 14 weeks of age to 0.139 +/- 0.061 U Tyrosin/l in both groups. From the 18th week of age the naturally raised fallow deer, infected with gastrointestinal nematodes, had significantly higher pepsinogen values than the helminth free kept animals. Maximum pepsinogen levels in the naturally raised fallow deer were determined in November 1992 (0.813 +/- 0.336 U Tyrosin/l) and in June 1993 (1.050 +/- 0.163 U Tyrosin/l). In helminth free animals no further decrease of plasma pepsinogen values was seen from 14th week of age onwards: it was 0.202 +/- 0.110 U Tyrosin/l. There was no influence of sex on the plasma pepsinogen values in both groups.

Evaluation of a new reflectance photometer for use in home blood glucose monitoring

A new reflectance photometer (Glucometer, Ames Division, Miles Laboratories, Elkhart, Indiana) has been developed for use with the Dextrostix reagent strip. The device measures 8 X 17 cm, weighs 330 g, uses AA batteries, and requires no warm-up. High (330 mg/dl) and low (50 mg/dl) calibrations are stored in memory and need be repeated only when: (1) a control solution (100 mg/dl) reading is in error, (2) ambient temperature changes by more than 5 degrees C, (3) a new bottle of Dextrostix is used, and (4) batteries are changed. A 60-s timer with alarm helps make timing of the procedure consistent. Nineteen insulin-dependent and one non-insulin-dependent diabetic subjects each performed a minimum of 20 blood glucose determinations over a 3-mo period in the investigators' laboratories. Simultaneous capillary blood samples were obtained for plasma glucose analysis by a comparative method. A total of 602 patient-determined glucose values ranging from 30 to 400 mg/dl were compared with simultaneous laboratory values. These values correlated significantly (r = 0.96, P less than 0.0001, y = 2.6 + 0.92x). The Glucometer-Dextrostix System is an accurate and convenient method for home blood glucose monitoring by diabetic patients.