Intensive Intravenous Infusion of Insulin in Diabetic Cats

Background

Remission occurs in 10–50% of cats with diabetes mellitus (DM). It is assumed that intensive treatment improves β‐cell function and increases remission rates.

Hypothesis

Initial intravenous infusion of insulin that achieves tight glycemic control decreases subsequent insulin requirements and increases remission rate in diabetic cats.

Animals

Thirty cats with newly diagnosed DM.

Methods

Prospective study. Cats were randomly assigned to one of 2 groups. Cats in group 1 (n = 15) received intravenous infusion of insulin with the goal of maintaining blood glucose concentrations at 90–180 mg/dL, for 6 days. Cats in group 2 (n = 15) received subcutaneous injections of insulin glargine (cats ≤4 kg: 0.5–1.0 IU, q12h; >4 kg 1.5–2.0 IU, q12h), for 6 days. Thereafter, all cats were treated with subcutaneous injections of insulin glargine and followed up for 6 months. Cats were considered in remission when euglycemia occurred for ≥4 weeks without the administration of insulin. Nonparametric tests were used for statistical analysis.

Results

In groups 1 and 2, remission was achieved in 10/15 and in 7/14 cats (P = .46), and good metabolic control was achieved in 3/5 and in 1/7 cats (P = .22), respectively. Overall, good metabolic control or remission occurred in 13/15 cats of group 1 and in 8/14 cats of group 2. In group 1, the median insulin dosage given during the 6‐month follow‐up was significantly lower than in group 2 (group 1: 0.32 IU/kg/day, group 2: 0.51 IU/kg/day; P = .013).

Conclusions and Clinical Importance

Initial intravenous infusion of insulin for tight glycemic control in cats with DM decreases insulin requirements during the subsequent 6 months.     

Anaerobiosis and a theory of growth line formation

Microstructural growth increments within the shells of numerous Recent and fossil molluscs are interpreted as reflections of alternating periods of shell deposition and dissolution, occurring during aerobic and anaerobic respiration, respectively. The acidic end products of anaerobic metabolism are neutralized by calcium carbonate from the shell, leaving a relatively insoluble organic residue at the mantle-shell interface. With the return of oxygenated conditions and resumption of aerobic respiration, this organic material is reincorporated within the shell. Inasmuch as metabolic changes are often synchronized with lunar or solar cycles (or both), we are led to the nearly paradoxical conclusion that, as a result of shell destructive processes, a relatively complete and detailed record of both short- and long-term growth is often preserved within the molluscan exoskeleton. Analyses of relationships between ambient oxygen concentrations and shell structural types may eventually prove useful, in paleoecological studies, for determination of dissolved oxygen gradients in Phanerozoic marine environments.     

Titan: discovery of carbon monoxide in its atmosphere

The 3-0 rotation-vibration band of carbon monoxide in the near-infrared spectrum of Titan has been identified, and a reflecting layer model mixing ratio of carbon monoxide to molecular nitrogen of 6 x 10(-5) has been determined. This result supports the probable detection of carbon dioxide by Samuelson and his co-workers and strengthens possible analogies between the atmosphere of Titan and conditions on primitive Earth.     

CB1 cannabinoid receptors and on-demand defense against excitotoxicity

Abnormally high spiking activity can damage neurons. Signaling systems to protect neurons from the consequences of abnormal discharge activity have been postulated. We generated conditional mutant mice that lack expression of the cannabinoid receptor type 1 in principal forebrain neurons but not in adjacent inhibitory interneurons. In mutant mice,the excitotoxin kainic acid (KA) induced excessive seizures in vivo. The threshold to KA-induced neuronal excitation in vitro was severely reduced in hippocampal pyramidal neurons of mutants. KA administration rapidly raised hippocampal levels of anandamide and induced protective mechanisms in wild-type principal hippocampal neurons. These protective mechanisms could not be triggered in mutant mice. The endogenous cannabinoid system thus provides on-demand protection against acute excitotoxicity in central nervous system neurons.     

Growth of bivalves at deep-sea hydrothermal vents along the galapagos rift

Direct measurements of shell growth of an unclassified mussel from active hydrothermal vents along the Galápagos Rift reveal growth rates of approxmately 1 centimeter per year for mature specimens. The largest mussel collected (with shell length of 18.4 centimeters) was estimated to be 19 +/- 7 years old at the time of sampling. Recorded growth rates are among the highest documented for deep-sea species.     

Unsaponifiable lipid constituents of some underutilized tropical seed oils

Sterols, triterpene alcohols, and hydrocarbons present in the unsaponifiable fraction of some underutilized tropical seed oils have been examined.The seeds include Telfairia occidentalis (TLO), Andenopus breviflorus (ADB), Cucumeropsis edulis (CME), Antiaris africana (ATF), and Monodora tenuifolia (MNT). The oil content of the seeds was high (34.7-68.8%), whereas triacylglycerols comprised the dominant lipid group in the oils (65.4-73.9%). The percentage of unsaponifiables ranged from 1.1 to 7.9%. Ten sterols were identified in the fractions. In the Cucurbitaceae oils (TLO, CME, and ADB), Delta(7)-sterols constituted the dominant sterols. These include 24-ethylcholesta-7,22E,25-trienol (7), 24-ethylcholesta-7,25-dienol (9), 24Z-ethylidenecholes-7-enol (10), and 24-ethylcholesta-7, 24-dienol (11). However Delta(5)-sterols (1-5) occurred at the highest concentration in the other two samples (ATF and MNT). Fifteeen triterpene alcohols were detected in the fractions. Olean-12-enol (16), isomultiflorenol (8), and lupeol (23) were the dominant alcohols in the Cucurbitaceae family, whereas alpha-amyrin (urs-12-enol) (20) was the dominant triterpene alcohol in ATF and MNT. A mixture of C(18)-C(34) n-alkanes, squalene, and some monoterpenes was detected in the hydrocarbon fraction.