Lower BG Research Articles

Contradiction with enzymatic stoichiometry theory: Persistent low ratios of β-glucosidase to phosphomonoesterase following 10-year continuous phosphorus fertilization in three subtropical forests

The ratio of β-glucosidase (BG) to phosphomonoesterase (PME) activity (BG:PME) is often used to predict the intensity of microbial phosphorus (P) shortage, with lower BG:PME indicating stronger P shortage (enzymatic stoichiometry theory). Here, we demonstrated that 10-year continuous P fertilization as high as 150 kg P ha−1 yr−1 in the form of NaH2PO4 solution did not elevate the BG:PME up to the level of other terrestrial ecosystems. The BG:PME of primary, secondary, and planted forests were 0.094, 0.067, and 0.089, respectively in P-fertilized plots, which were much lower than global average (0.62 ± 0.04), despite the fact that Bray-extracted P contents were substantially elevated (more than 600 times). Thus, the findings of the current study suggest that BG:PME overestimates P shortage in our P-enriched forests, implying that the enzymatic stoichiometry theory may not be universally applicable.

Empirical evidence challenges the effectiveness of the enzymatic stoichiometry of glucosidase and phosphatase as an indicator of microbial C vs P limitation

The ratio of β-1,4-glucosidase (BG) to acid/alkaline phosphomonoesterase (AP) (BG:AP) is commonly employed as an indicator to assess the relative microbial limitations of carbon (C) and phosphorus (P), whereby a higher BG:AP ratio suggests stronger C limitations. This approach is based on the assumption that BG and AP can represent enzymes targeting C and P, respectively. Nevertheless, it is crucial to recognize that microbial C and P acquisition involves the participation of other enzymes alongside BG and AP, and thus, the capacity of BG and AP to accurately and comprehensively represent the entire spectrum of C and P acquisition is questionable. Here, analyzing previously published data, I present a piece of empirical evidence that challenges the suitability of the BG:AP ratio as an accurate indicator of microbial limitations concerning C vs P. P fertilization decreased BG:AP in up to 27 % out of the total 109 observations, which represents a clear contradiction, as this outcome is interpreted by the enzymatic stoichiometry approach as indicating an intensified P limitation arising from P fertilization. Furthermore, the effect of P fertilization on the BG:AP ratio did not show significant differences between experimental sites characterized by higher BG:AP ratios (indicative of lesser P limitation) and those with lower BG:AP ratios (indicative of greater P limitation). Consequently, I conclude that the BG:AP ratio inadequately reflects microbial C vs P limitations.

The Effect of High-Intensity Interval Exercise on Short-Term Glycaemic Control, Serum Level of Key Mediator in Hypoxia and Pro-Inflammatory Cytokines in Patients with Type 1 Diabetes-An Exploratory Case Study.

Type 1 diabetes (T1D) is associated with hyperglycaemia-induced hypoxia and inflammation. This study assessed the effects of a single bout of high-intensity interval exercise (HIIE) on glycaemia (BG) and serum level of pro-inflammatory cytokines, and an essential mediator of adaptive response to hypoxia in T1D patients. The macronutrient intake was also evaluated. Nine patients suffering from T1D for about 12 years and nine healthy individuals (CG) were enrolled and completed one session of HIIE at the intensity of 120% lactate threshold with a duration of 4 × 5 min intermittent with 5 min rests after each bout of exercise. Capillary and venous blood were withdrawn at rest, immediately after and at 24 h post-HIIE for analysis of BG, hypoxia-inducible factor alpha (HIF-1α), tumour necrosis factor alpha (TNF-α) and vascular-endothelial growth factor (VEGF). Pre-exercise BG was significantly higher in the T1D patients compared to the CG (p = 0.043). HIIE led to a significant decline in T1D patients' BG (p = 0.027) and a tendency for a lower BG at 24 h post-HIIE vs. pre-HIIE. HIF-1α was significantly elevated in the T1D patients compared to CG and there was a trend for HIF-1α to decline, and for VEGF and TNF-α to increase in response to HIIE in the T1D group. Both groups consumed more and less than the recommended amounts of protein and fat, respectively. In the T1D group, a tendency for a higher digestible carbohydrate intake and more frequent hyperglycaemic episodes on the day after HIIE were observed. HIIE was effective in reducing T1D patients' glycaemia and improving short-term glycaemic control. HIIE has the potential to improve adaptive response to hypoxia by elevating the serum level of VEGF. Patients' diet and level of physical activity should be screened on a regular basis, and they should be educated on the glycaemic effects of digestible carbohydrates.

The ratio of β-1,4-glucosidase activity to phosphomonoesterase activity remains low in phosphorus-fertilized tropical soils: A meta-analysis

The ratio of β-1,4-glucosidase (BG) activity to phosphomonoesterase (PME) activity (BG:PME) in soil is an indicator of microbial phosphorus (P) demand, with lower BG:PME ratios indicating greater P shortages. In this study, I performed a meta-analysis to investigate the impact of P fertilization on the BG:PME ratios of P-poor tropical soils. Linear mixed-effects model analysis demonstrated that the BG:PME ratio was lower in tropical soils than other soils, reflecting higher microbial P demand in P-poor tropical soils compared to those in other regions. P fertilization significantly elevated the BG:PME ratio, indicating microbial P requirement was satisfied to some extent. However, the BG:PME ratios of tropical soils never reached the global average, even under continuous, long-term fertilization, although P fertilization often substantially increased the available P content of tropical soils. This result may indicate that the usage of the BG:PME ratio as an indicator of microbial P demand could overestimate the P shortages in tropical soils. On the other hand, it is also possible that soil available P content, which is often used as an indicator of soil P richness, does not necessarily reflect available P for soil microorganisms. Validating the BG:PME ratio as an indicator of microbial P demand could improve our understanding of microbial P shortage in tropical ecosystems.

Abstract 1122‐000091: Predictors of Symptomatic Hemorrhagic Transformation After Mechanical Thrombectomy in Acute Ischemic Stroke

Introduction : Mechanical thrombectomy (MT) has become the current standard of care for large vessel occlusion stroke but is associated with an increased risk of intracranial hemorrhage (ICH). Although several studies have investigated the risk factors, there is still limited, not well‐established data. This study aims to evaluate the risk factors of HT after MT. Methods : We retrospectively reviewed all MT patients who were treated at a single comprehensive stroke center from 12/2016 to 7/2019. Variables included initial NIHSS, blood glucose, initial systolic blood pressure, age, gender, IV tPA, time from door to recanalization, and TICI score. Outcome measures were HT on post‐procedure or 24‐hour post‐tPA head CT/MRI as well as modified Rankin scale (mRS) upon discharge. Results : Among 74 patients (68.8 ± 14 years, men 47.3%), 9 (12.2%) experienced hemorrhagic transformation after thrombectomy. Average admitting NIHSS was significantly higher in the HT group (22 vs 16.8, p = 0.041). TICI 3 after MT was protective for HT (OR 0.078, 95% CI 0.009‐0.663). IV tPA (OR 3.86, 95% CI 1.448‐10.326) was associated with good neurological outcome at discharge (mRS < = 2), but HT was not (OR 0.114, 95% CI 0.013‐0.964). Patients with mRS < = 2 upon discharge were younger (65.2±12 vs 71.9±15, p = 0.04) and had lower initial BG (124±45.8 vs 157±69.6, P = 0.02). Conclusions : TICI 3 score, decreased NIHSS, and lower BG were associated with less HT and better outcomes in our MT cohort. Admitting NIHSS > = 20 may be a reasonable threshold to predict HT after MT. Our findings are consistent with the TICI‐ASPECTS‐glucose (TAG) score to predict sICH; however, we used initial NIHSS as a surrogate for ASPECTS. Further studies may utilize additional quantitative measures such as CTP data to predict HT.

Does the ratio of β-1,4-glucosidase to β-1,4-N-acetylglucosaminidase indicate the relative resource allocation of soil microbes to C and N acquisition?

The ratio of β-1,4-glucosidase (BG) to β-1,4-N-acetylglucosaminidase (NAG) activity (BG:NAG ratio) is often used as an indicator of the relative resource allocation of soil microbes to C acquisition compared with N (the ecoenzymatic stoichiometry hypothesis). An increasing number of recent studies have used this index to assess the nutrient status of microbes. However, the validity of this index for assessing the nutrient status of microbes is not well tested. In this study, we collected published data and tested that validity by investigating whether N fertilization elevated the BG:NAG ratio, to test the assumption derived from the ecoenzymatic stoichiometry hypothesis that microbes reduce their allocation to the N-acquiring enzyme (NAG) under N-enriched conditions. Of the observations, 54% (82/151) did not support the hypothesis because those studies showed lower BG:NAG ratios in N-enriched soils than under ambient conditions (i.e., N was not enriched), especially when the ambient BG:NAG ratio was higher than 2.0 (77%, 59/77). This suggests that the BG:NAG ratio does not necessarily indicate the microbial status for C or N limitation. Rather, we hypothesized that NAG targets chitin or peptidoglycan, which accumulate at later stages of decomposition and that the variation in BG:NAG explains the decomposition stage. A negative correlation of BG:NAG ratio with polyphenol oxidase activity, which generally increases with decomposition, supported our hypothesis.

Soil ecoenzymatic stoichiometry and microbial resource limitation driven by thinning practices and season types in Larix principis-rupprechtii plantations in North China

The extracellular ecoenzymatic stoichiometry (EES) of the soil are key indicators of the nutritional status and relative resource limitations of microbes that play important roles in biogeochemical cycling and ecosystem functions. However, our knowledge of the effects of forest thinning and the seasons on the variability of extracellular ecoenzymatic activities (EEA) and EES in the soil is limited. We examined the soils from Larix principis-rupprechtii plantations after nine years of treatments with four different thinning intensities (i.e., control (CK), low thinning (LT), moderate thinning (MT), and high thinning (HT)) in four different seasons. We measured the activities of one carbon (C) acquiring enzyme (β-1,4-glucosidase (BG)), two nitrogen (N) acquiring enzymes (β-1,4-N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP)), and one phosphorus (P) acquiring enzyme (acid phosphatase (AP)), and examined potential factors (soil environment, nutrients, and microbial biomass) that may influence the activities of these enzymes. Our results showed that thinning significantly (p < 0.05) enhanced the activities of the BG, NAG + LAP, and AP. The EEA were higher in summer and autumn than those in spring and winter. Further, MT and HT stands exhibited lower BG:(NAG + LAP) and higher (NAG + LAP):AP ratios than the CK and LT stands, demonstrating that MT and HT caused a greater N limitation for soil microbes. The higher (NAG + LAP):AP ratio during winter indicated that the microbial N limitation was increased in this season. The variations in the EEA, EES, environment, nutrients, and microbial biomass in the soil among different thinning treatments demonstrated that thinning could markedly promote microbial activities and metabolism and improve nutrient cycling. Based on analyses of the BG:(NAG + LAP) ratio, (NAG + LAP):AP ratio, and the threshold element ratio, we found that the metabolism of soil microbes was limited by N in L. principis-rupprechtii plantations in North China. A redundancy analysis and a variation partitioning analysis revealed that variations in the EEA and EES of soils could attributed to the alterations in soil properties, especially soil nutrient and microbial biomass. Overall, the ecoenzymatic C:N:P stoichiometry was dependent on the resource availability in the soils rather than on homeostatic mechanisms. Our research highlights the importance of the effects of thinning practices and season types on ecoenzymes and microbial metabolism, and provides insights into the microbial resource limitation, nutrient cycling, and ecological processes in plantation forests after thinning.

Canagliflozin Improves Glycemic Control and Beta-Cell Mass in the TallyHo Polygenic Model of Type 2 Diabetes

SGLT2 inhibitors reduce insulin resistance and may improve beta-cell function in humans with T2D. We studied the effects of Canagliflozin (Cana) on glucose homeostasis, islet architecture and endocrine cell fate in male TallyHO/JngJ (TH) mice, a new model of T2D, which mimics many aspects of polygenic T2D in humans. By 8 weeks of age, all TH mice developed moderate obesity and hyperglycemia compared to control SWR/J mice; ∼60% of TH mice converted quickly to overt diabetes, characterized by elevated BG values (&amp;gt;400mg/dL) (HG mice), while the remaining cohort maintained lower BG values (250-400mg/dL) until the end of the study (LG mice). Mice from both groups (HG, LG) were then randomized to receive Chow or Chow-containing Cana (100ppm) diet for 10 weeks, prior to sacrifice. Cana treatment significantly decreased the fasting BG levels only in the HG mice (HG/Cana) compared with untreated HG/Chow mice (207.7±34.6 vs. 452.2±163.4mg/dL, p&amp;lt;0.0001), improved glucose and insulin excursion curves during an ipGTT (p&amp;lt;0.0001 for AUC values) and decreased HbA1c values (4.3±0.7 vs. 6.2±0.93%, p&amp;lt;0.0001). Non-fasting plasma insulin and C-peptide levels, pancreatic insulin content and HOMA-B index were all significantly higher in HG/Cana than in HG/Chow mice, suggesting improved beta-cell function by Cana. Immunofluorescence staining for islet hormones showed that, compared to untreated animals, Cana reestablished the islet area and the beta-cell number/islet in HG mice (possibly due to reduced apoptosis of beta-cells), in addition to decreased number of alpha- and delta-cells/islet. In HG/Cana mice, the majority of Ins+ cells expressed the glucose transporter Glut2, while its expression was undetectable in Ins+ cells of the HG/Chow mice, further suggesting an improvement in glucose sensing capability of beta-cells with Cana treatment. Our study shows that Cana has beneficial effects on preserving beta-cell mass, identity and function in a model of early onset T2D. Disclosure I. Popescu: None. G.M. Mussman: None. C.B. Hughes: None. T.J. Janes: None. P. Ray: None. R. Bunn: None. J. Fowlkes: None. K.M. Thrailkill: None.

Glycemic Outcomes 3 Years After Implementation of a Peri-Operative Glycemic Control Algorithm in an Academic Institution

While hyperglycemia in the postoperative setting has been linked to an increase in surgical complications, limited data are available to inform the management of patients with diabetes in the operating room and the immediate peri-operative period. We describe the results of a peri-operative glycemic control program that standardized intravenous insulin with a target glucose (BG) range of 120 to 180 mg/dL for patients with diabetes presenting with a BG level >180 mg/dL and included transition to subcutaneous insulin. Patients with known diabetes and a BG >180 mg/dL who underwent surgery were included. The control group included 260 patients from March 2, 2008 through December 31, 2008. The intervention group included 588 patients following protocol implementation from April 1, 2009 through December 31, 2012. Data included demographic information, hospital BG values, length of stay (LOS), mortality, and wound infections. The intervention group had significantly lower BG on arrival in the postoperative care unit (182.2 vs 194.9 mg/dL, P = .012). Mean BG during the first 24 hours after surgery was lower in the intervention group (182.1 vs. 190.5 mg/dL), and there were fewer BG values >200 mg/dL in the intervention group (P = .005). The percentage of BG values <70 mg/dL during the hospital stay was lower in the intervention group (1.94 vs. 2.43%, P<.01). There was no significant difference in mortality, LOS, or wound infections. Following implementation of a hospital-wide peri-operative glycemic control algorithm, we found a reduction in peri-operative BG levels and hypoglycemia rates. Ongoing research is needed to assess the impact on clinical outcomes. BG = blood glucose CCI = Charlson comorbidity index EHR = electronic health record ICD-9 = International Classification of Disease-9 IV = intravenous LOS = length of stay OR = operating room PACU = postoperative care unit POC = point-of-care.

Hospitalization costs and clinical outcomes in CABG patients treated with intensive insulin therapy

BackgroundThe financial impact of intensive (blood glucose [BG] 100–140mg/dl [5.5–7.8mM] vs. conservative (141–180mg/dl (7.9–10.0mM) glucose control in the ICU in patients, with and without diabetes, undergoing coronary artery bypass graft (CABG) surgery is not known. MethodsThis post-hoc cost analysis determined differences in hospitalization costs, resource utilization and perioperative complications in 288 CABG patients with diabetes (n=143) and without diabetes (n=145), randomized to intensive (n=143) and conservative (n=145) glucose control. ResultsIntensive glucose control resulted in lower BG (131.4±14mg/dl-(7.2±0.8mM) vs. 151.6±17mg/dl (8.4±0.8mM, p<0.001), a nonsignificant reduction in the median length of stay (LOS, 7.9 vs. 8.5days, p=0.17) and in a composite of perioperative complications including wound infection, bacteremia, acute renal and respiratory failure, major cardiovascular events (42% vs 52%, p=0.10) compared to conservative control. Median hospitalization costs were lower in the intensive group ($39,366 vs. $42,141, p=0.040), with a total cost savings of $3654 (95% CI: $1780–$3723), than conservative control. Resource utilization for radiology (p=0.008), laboratory (p=0.014), consultation service (p=0.013), and ICU utilization (p=0.007) were also lower in the intensive group. Compared to patients without perioperative complications, those with complications had longer hospital length of stay (10.7days vs. 6.7days, p<0.001), higher total hospitalization cost ($48,299 vs. $32,675, p<0.001), and higher resource utilization units (2745 vs. 1710, p<0.001). ConclusionIntensive glycemic control [BG 100–140mg/dl (5.5–7.8mM)] in patients undergoing CABG resulted in significant reductions in hospitalization costs and resource utilization compared to patients treated with conservative [BG 141–180mg/dl (7.9–10.0mM)] glucose control.

SGLT2 inhibitor empagliflozin reduces renal growth and albuminuria in proportion to hyperglycemia and prevents glomerular hyperfiltration in diabetic Akita mice

Our previous work has shown that gene knockout of the sodium-glucose cotransporter SGLT2 modestly lowered blood glucose in streptozotocin-diabetic mice (BG; from 470 to 300 mg/dl) and prevented glomerular hyperfiltration but did not attenuate albuminuria or renal growth and inflammation. Here we determined effects of the SGLT2 inhibitor empagliflozin (300 mg/kg of diet for 15 wk; corresponding to 60-80 mg·kg(-1)·day(-1)) in type 1 diabetic Akita mice that, opposite to streptozotocin-diabetes, upregulate renal SGLT2 expression. Akita diabetes, empagliflozin, and Akita + empagliflozin similarly increased renal membrane SGLT2 expression (by 38-56%) and reduced the expression of SGLT1 (by 33-37%) vs. vehicle-treated wild-type controls (WT). The diabetes-induced changes in SGLT2/SGLT1 protein expression are expected to enhance the BG-lowering potential of SGLT2 inhibition, and empagliflozin strongly lowered BG in Akita (means of 187-237 vs. 517-535 mg/dl in vehicle group; 100-140 mg/dl in WT). Empagliflozin modestly reduced GFR in WT (250 vs. 306 μl/min) and completely prevented the diabetes-induced increase in glomerular filtration rate (GFR) (255 vs. 397 μl/min). Empagliflozin attenuated increases in kidney weight and urinary albumin/creatinine ratio in Akita in proportion to hyperglycemia. Empagliflozin did not increase urinary glucose/creatinine ratios in Akita, indicating the reduction in filtered glucose balanced the inhibition of glucose reabsorption. Empagliflozin attenuated/prevented the increase in systolic blood pressure, glomerular size, and molecular markers of kidney growth, inflammation, and gluconeogenesis in Akita. We propose that SGLT2 inhibition can lower GFR independent of reducing BG (consistent with the tubular hypothesis of diabetic glomerular hyperfiltration), while attenuation of albuminuria, kidney growth, and inflammation in the early diabetic kidney may mostly be secondary to lower BG.

The susceptibility of soil enzymes to inhibition by leaf litter tannins is dependent on the tannin chemistry, enzyme class and vegetation history

By inhibiting soil enzymes, tannins play an important role in soil carbon (C) and nitrogen (N) mineralization. The role of tannin chemistry in this inhibitory process, in conjunction with enzyme classes and isoforms, is less well understood. Here, we compared the inhibition efficiencies of mixed tannins (MTs, mostly limited to angiosperms) and condensed tannins (CTs, produced mostly by gymnosperms) against the potential activity of β-glucosidase (BG), N-acetyl-glucosaminidase (NAG), and peroxidase in two soils that differed in their vegetation histories. Compared with CTs, MTs exhibited 50% more inhibition of almond (Prunus dulcis) BG activity and greater inhibition of the potential NAG activity in the gymnosperm-acclimatized soils. CTs exhibited lower BG inhibition in the angiosperm-acclimated soils, whereas both types of tannins exhibited higher peroxidase inhibition in the angiosperm soils than in gymnosperm soils. At all of the tested tannin concentrations, irrespective of the tannin type and site history, the potential peroxidase activity was inhibited two-fold more than the hydrolase activity and was positively associated with the redox-buffering efficiency of tannins. Our finding that the inhibitory activities and mechanisms of MTs and CTs are dependent on the vegetative history and enzyme class is novel and furthers our understanding of the role of tannins and soil isoenzymes in decomposition.

Reexamining the evidence for inpatient glucose control: New recommendations for glycemic targets

To review the risks of hyperglycemia in hospitalized patients, data supporting the benefits of treating hyperglycemia, and recommendations from the 2009 American Association of Clinical Endocrinologists and American Diabetes Association consensus statement on the management of inpatient hyperglycemia. Inpatient hyperglycemia is common, costly, and associated with poor clinical outcomes in many disease states. Despite inconsistencies in clinical trial results, good glucose management in the hospital remains important. Target blood glucose concentrations (BGs) were recently modified to somewhat higher values with the expectation that the benefit of treatment will persist with a lower risk of hypoglycemia, which is itself another marker of poor outcome in critically and non-critically ill patients. In the intensive care unit (ICU), the threshold to start treatment is a BG of <or=180 mg/dL. I.V. insulin is the treatment of choice in critically ill patients because of its rapid onset and offset of action. Once i.v. insulin is started, the BG should be maintained between 140 and 180 mg/ dL; a lower BG target (110-140 mg/dL) may be appropriate in selected patients. Targets of <110 mg/dL or >180 mg/dL are no longer recommended. In non-critically ill patients, premeal BG targets are <140 mg/dL; random BGs of <180 mg/dL are recommended. Scheduled subcutaneous insulin is the treatment of choice for hyperglycemia in non-critically ill patients; use of sliding-scale insulin is strongly discouraged. To avoid hypoglycemia, insulin regimens should be reassessed if BG falls to <100 mg/dL. Poor glycemic control in the hospital setting is a quality-of-care, safety, and cost issue. Safe and effective strategies to implement optimal glycemic control require multidisciplinary involvement. Insulin given i.v. in the ICU or subcutaneously on an as-scheduled regimen in other parts of the hospital is the treatment of choice.

Is There Any Role of Resecting the Stomach to Ameliorate Weight Loss and Sugar Control in Morbidly Obese Diabetic Patients?

Among the restrictive procedures the role of restrictive vs. resecting the stomach is still ambiguous. This study evaluate which is the role of the stomach with respect to blood glucose levels (BG) and percent excess weight loss (EWL) over the 18 months after restrictive procedures in morbid obese diabetic patients. We retrospectively compared a group of patients who underwent partial gastrectomy (just part of the gastric body) with gastric banding (GBSR; n=27), sleeve gastrectomy (part of gastric body and complete fundus resection; LSG; n=53) to laparoscopic gastric banding (LAGB; n=100). Differences among groups at 3, 6, 12, and 18 months were evaluated by analysis of variance. The three cohorts were diabetic patients similar in BMI, age, and gender. At 12 and 18 months, LSG had higher EWL (P<0.05) and lower BG (P<0.05) than did either LAGB or GBSR. There were no operative deaths. LAGB-two staple-line oozing, two wound infections; LSG-one hemorrhage, two staple-line oozing, two leaks; GBSR-one hemorrhage, two wound infections. All complications were readily treated. LSG provides better weight loss and glucose control at 1 year and 1.5 years after surgery than does either LAGB or GBSR, suggesting that gastric fundus resection plays an important, not yet well-defined, role.

Prevalence of nocturnal hypoglycemia in first trimester of pregnancy in patients with insulin treated diabetes mellitus

Excellent metabolic control before conception and during diabetic pregnancies is the aim in order to avoid malformations and perinatal morbidity. Since an inverse correlation between median blood glucose concentration (BG) and hypoglycemia as well as a high prevalence of nocturnal hypoglycemia have been described, we investigated the frequency of nocturnal hypoglycemia and the predictive value of bedtime blood glucose concentration for development of this condition in insulin treated diabetic patients. During hospitalization, with no other changes in the patients' normal schedules, hourly blood samples were drawn from an iv-cannula from 22.00 h to 07.00 h for one night. BG (venous whole blood) and hemoglobin A1c were determined the following day. Fifty-three patients participated; subsequently ten were excluded due to discontinuation of blood sampling during the night, caused by either discomfort or cannula problems. Of the remaining 43 patients, 16 (37%) had at least one blood glucose <3.0 mmol/l. The duration of hypoglycemia was 2.4 (1-7) h with the highest prevalence at 05 h. Only one patient felt hypoglycemic during the night. Hemoglobin A1c was similar in patients with (7.1+/-1.2%, mean+/-s.d.) and without (6.8+/-0.8%) nocturnal hypoglycemia. Women with nocturnal hypoglycemia had significantly lower BG before bedtime compared to patients without hypoglycemia, 6.4+/-3.6 mmol/l vs. 7.9+/-2.4 mmol/l, p<0.05. The best predictive value for nocturnal hypoglycemia was a BG below 6.0 mmol/l at 23.00, which resulted in a risk of nocturnal hypoglycemia of 71%. Conversely, if the BG was > or =6.0 mmol/l, the chance of avoiding nocturnal hypoglycemia was 83%. Nocturnal hypoglycemia was seen with a prevalence of 37% during a night in the first trimester of pregnancy in insulin treated patients. Only one patient registered the hypoglycemia. Nocturnal hypoglycemia could be predicted in the majority of patients by measurements of BG before bedtime.

Interindividual comparability of blood glucose alterations after meals of complex carbohydrates

Young male and female probands underwent an DGTT (oral glucose tolerance test) using a glucose load of 1 g/kg b.wt. The alterations in blood glucose levels were checked and plotted by a Biostator. A week later groups of those probands were fed an isocaloric meal of complex CH, namely either potatoes, noodles or white bread. The resulting BG curves were also checked by a Biostator. It turned out that: 1. the shapes of the BG curves after glucose load were not interindividually comparable. 2. there was neither a similarity of the shapes of the BG curves within the groups after any of the different CH levels. 3. But if one compares the shape of the BG curves after glucose load and after a meal of any of the complex CH of one and the same person, there is a striking similarity in those curve shapes. The differences between them lie just in the mostly lower BG values of the curves after CH meals compared with those after glucose load. 4. Therefore the resulting graph of both of those curves is in all observed cases a straight line with a probability better than 0.001, called OGTT-calibrating resulting graph.

CARACTÉRISTIQUES DES SOLS SULFATÉS ACIDES DE LA SÉRIE DE L'ANSE EN MILIEU ESTUARIEN (QUÉBEC)

Acid sulfate soils were sampled according to the transect method in four bays along the south shore of the St. Lawrence river to determine their properties in their area of distribution. In each bay, six profiles of cultivated soils were sampled along a transect perpendicular to the river. One non-cultivated profile was also sampled at l'Isle-Verte. The lower limit of the B horizons, between 79 and 89 cm, suggested a homogeneous development of these soils across the area. Most profiles contained jarosite in the lower Bg and, sometimes, in the C horizons; this mineral was absent in the upper part of the profiles of soils that had been limed prior to cultivation. Total S content increased with depth, but only a few horizons had a content &gt; 0.75% presumably because of sulfate leaching once the soils were drained. Organic C content in the de l'Anse soils decreased less rapidly with depth than in other gleysolic soils, because vegetation grew while sediments were being deposited. Key words: Acid sulfate soils, total S, recent marine sediments, jarosite