Promising PEGylated cationic dendrimers for delivery of miRNAs as a possible therapy against HIV-1 infection.

BACKGROUND: The appearance of resistance against new treatments and the fact that HIV-1 can infect various cell types and develop reservoirs and sanctuaries makes it necessary to develop new therapeutic approaches to overcome those failures. RESULTS: Studies of cytotoxicity, genotoxicity, complexes formation, stability, resistance, release and particle size distribution confirmed that G2-SN15-PEG, G3-SN31-PEG, G2-SN15-PEG-FITC and G3-SN31-PEG-FITC dendrimers can form complexes with miRNAs being biocompatible, stable and conferring protection to these nucleic acids. Confocal microscopy and flow cytometry showed effective delivery of these four dendrimers into the target cells, confirming their applicability as delivery systems. Dendriplexes formed with the dendrimers and miRNAs significantly inhibited HIV-1 infection in PBMCs. CONCLUSIONS: These dendrimers are efficient delivery systems for miRNAs and they specifically and significantly improved the anti-R5-HIV-1 activity of these RNA molecules.

Microscale Generation of Entangled Photons without Momentum Conservation.

We report, for the first time, the observation of spontaneous parametric down-conversion (SPDC) free of phase matching (momentum conservation). We alleviate the need to conserve momentum by exploiting the position-momentum uncertainty relation and using a planar geometry source, a 6 µm thick layer of lithium niobate. Nonphase-matched SPDC opens up a new platform on which to investigate fundamental quantum effects but it also has practical applications. The ultrasmall thickness leads to a frequency spectrum an order of magnitude broader than that of phase-matched SPDC. The strong two-photon correlations are still preserved due to energy conservation. This results in ultrashort temporal correlation widths and huge frequency entanglement. The studies we make here can be considered as the initial steps into the emerging field of nonlinear quantum optics on the microscale and nanoscale.

Synthesis and in vitro activity of new biguanide-containing dendrimers on pathogenic isolates of Acanthamoeba polyphaga and Acanthamoeba griffini.

The genus Acanthamoeba can cause Acanthamoeba keratitis (AK) and granulomatous amoebic encephalitis (GAE). The treatment of these illnesses is hampered by the existence of a resistance stage that many times causes infection relapses. In an attempt to add new agents to our chemotherapeutic arsenal against acanthamebiasis, two Acanthamoeba isolates were treated in vitro with newly synthesized biguanide dendrimers. Trophozoite viability analysis and ultrastructural studies showed that dendrimers prevent encystment by lysing the cellular membrane of the amoeba. Moreover, one of the dendrimers showed low toxicity when tested on mammalian cell cultures, which suggest that it might be eventually used as an amoebicidal drug or as a disinfection compound in contact lens solutions.

[Executive functions in patients with obstructive sleep apnea: exploring the prefrontal model]. / Funciones ejecutivas en pacientes con apnea obstructiva del sueño: explorando el modelo prefrontal.

INTRODUCTION: According to the prefrontal model, individuals with obstructive sleep apnea (OSA) manifest behaviours mimicking dysexecutive syndrome as a result of blood gas abnormalities and sleep fragmentation. OBJECTIVE: To compare executive functions in OSA patients with normative values and explore their relationship with blood gas abnormalities and sleep fragmentation. PATIENTS AND METHODS: Patients were recruited from the wider community and from a tertiary care hospital. The score obtained in the neuropsychological assessment was compared with Student's t-test for a sample. A multiple linear regression analysis was subsequently estimated, using polysomnographic parameters of hypercapnia, hypoxemia and sleep fragmentation as the predictor variables, and the executive function score as the variable to be predicted. RESULTS: Although the neuropsychological assessment performance of 26% of this sample was classified as executive impairment, indicators of sleep fragmentation and gas abnormalities failed to predict the performance of executive functions. CONCLUSION: A proportion of the patients with OSA presented performance similar to a dysexecutive syndrome; however, the factors underlying and fostering this type of cognitive manifestation remain unclear. Early treatment for this public health problem could be the best tool available for improving quality of life and preventing health risks.

TITLE: Funciones ejecutivas en pacientes con apnea obstructiva del sueño: explorando el modelo prefrontal.Introducción. El modelo prefrontal propone que los individuos con apnea obstructiva del sueño (AOS) manifiestan conductas similares a un síndrome disejecutivo como resultado de las alteraciones de gases en la sangre y la fragmentación del sueño. Objetivo. Comparar las funciones ejecutivas en pacientes con AOS con valores normativos y explorar su relación con las alteraciones de gases en la sangre y la fragmentación del sueño. Pacientes y métodos. Se reclutó a pacientes de la comunidad general y de un hospital de tercer nivel. La puntuación obtenida en la evaluación neuropsicológica se contrastó con la t de Student para una muestra. Posteriormente, se estimó un análisis de regresión lineal múltiple mediante parámetros polisomnográficos de hipercapnia, hipoxemia y fragmentación del sueño como variables predictoras, y la puntuación de funciones ejecutivas como variable que se debe predecir. Resultados. Pese a que el desempeño en la evaluación neuropsicológica del 26% de esta muestra se clasificó como alteración ejecutiva, los indicadores de fragmentación del sueño y alteraciones de gases no predijeron el desempeño ejecutivo. Conclusión. Una fracción de los pacientes con AOS mostró un desempeño similar a un síndrome disejecutivo; no obstante, permanecen indefinidos los factores que subyacen y favorecen este tipo de manifestaciones cognitivas. La atención temprana de este problema de salud pública podría ser la mejor herramienta disponible en aras de mejorar la calidad de vida y prevenir riesgos a la salud.

Sleep quality and memory function in healthy ageing.

OBJECTIVE: To study the relationship between sleep quality and memory in healthy ageing. METHODS: The study included 99 people older than 50 years (69 women and 30 men; mean age, 68.74 ± 7.18 years) with no associated diseases. Patients completed digital versions of the Word Learning (WL) and Visual Paired Associates (VPA) tests and the Pittsburgh Sleep Quality Index (PSQI) questionnaire to assess the quality of sleep. RESULTS: PSQI score was negatively correlated with VPA and WL test performance. Performance in these 2 memory tests decreased in line with sleep quality. In addition, performance in VPA test was negatively correlated with subjective sleep quality, duration, and sleep disturbances. Performance on the WL test was negatively correlated with subjective sleep quality and efficiency. Participants' sex showed a weak effect on VPA performance and sleep latency. CONCLUSIONS: Medical professionals working with elderly patients should take into consideration the effect of poor sleep quality on memory. Cognitive impairment in these patients may be a manifestation of a neuroendocrine imbalance due to a disrupted circadian rhythm. More research is needed to prove this hypothesis.

Amoebicidal activity of cationic carbosilane dendrons derived with 4-phenylbutyric acid against Acanthamoeba griffini and Acanthamoeba polyphaga trophozoites and cysts.

Amoebae from the genus Acanthamoeba are important pathogens responsible for severe illnesses in humans such as Acanthamoeba keratitis and granulomatous amoebic encephalitis. In the last few decades, AK diagnoses have steadily increased. Most patients suffering from AK were contact lens users and the infection was related to poor hygiene. However, therapy is not yet well established, and treatments may last for several months due to resistance. Moreover, these treatments have been described to generate cytotoxicity. Therefore, there is an urgent need to develop new therapeutic strategies against AK. In this study, the amoebicidal activity of different generation cationic carbosilane dendrons derived with 4-phenylbutyric acid was demonstrated against Acanthamoeba polyphaga and Acanthamoeba griffini trophozoites and cysts. In addition, the combination of chlorhexidine digluconate and the most effective dendron (ArCO2G2(SNMe3I)4) showed an in vitro effect against Acanthamoeba trophozoites and cysts, reducing the minimal trophozoite amoebicidal concentration as well as concentrations with cysticidal activity.

Evaluation of intracellular survival of Campylobacter fetus subsp. fetus in bovine endometrial cells by qPCR.

BACKGROUND: Campylobacter fetus subsp. fetus is the causal agent of sporadic abortion and infertility in bovines that produces economic losses in livestock. AIMS: This study evaluates the capability of C. fetus subsp. fetus to invade and survive in bovine endometrial epithelial cells and attempts to describe a pathogenic mechanism of this microorganism. METHODS: Primary culture of bovine endometrial epithelial cells was challenged with C. fetus subsp. fetus. Intracellular bacteria, represented by the number of genomic copies (g.c.) were quantified at 0, 2, 4, 10, and 24 hours post-infection (h.p.i.), by quantitative polymerase chain reaction (qPCR). The presence of intracellular bacteria was evaluated by immunofluorescence and immunohistochemistry. RESULTS: The results showed that only viable C. fetus subsp. fetus could invade endometrial cells. The g.c. number in assays with viable C. fetus subsp. fetus reached an average value of 656 g.c., remained constant until 4 h.p.i., then decreased to 100 g.c, at 24 h.p.i. In assays with non-viable microorganisms, the average value of g.c. was less than 1 g.c. and never changed. The intracellular presence of this bacteria was confirmed at 2 h.p.i. by immunofluorescence and immunohistochemistry. CONCLUSION: The results suggest that only C. fetus subsp. fetus viable can invade bovine endometrial epithelial cells but will not replicate in them, indicating that the endometrial cells do not represent a replication niche for this pathogen. Nonetheless, this invasion capability suggests that this type of cell could be employed by the pathogen to spread to other tissues.

Participation of interferon type I during canine parvovirus infection.

Canine parvovirus (CPV) is a single-stranded DNA virus that causes severe and fatal gastrointestinal diseases in dogs. CPV has developed several strategies to evade innate immune response mediated by type I interferons (IFN-I) to achieve a successful infection. The aim of this work was to evaluate the capability of CVP-2c to evade the IFN-I mediated response in infected cells. To establish the role of this response, the gene expression of interferon ß (IFNß), IFIT1, IFIT3, MAVS, and STING were estimated in MDCK cells infected with CPV-2c. Viral replication and gene expression was evaluated by quantitative PCR, also, a treatment with IFN-I (interferon omega) was included to confirm the role of IFN-I during CPV infection. The results revealed that CPV-2c infection stimulates the expression of IFNß moderately, in these cells. Due to low IFNß induction, the IFIT1 and IFIT3 expression were also low, and therefore CPV-2c was able to replicate in these cells. However, when the cells were treated with exogenous IFN-I, the IFNß expression was higher, leading to an increased gene expression of IFIT1 and IFIT3, responsible for antiviral control. The overexpression of these proteins reduced the expression of NS1 and VP2 viral genes and hence viral replication. MAVS and STING expression on infected cells showed a mild increase compared to IFNß, suggesting that the viral infection could partially modify its expression. All results obtained in this study showed that during CPV-2c infection in MDCK cells, the IFNß expression was altered since this cytokine is one of the most critical factors for the control and inhibition of viral replication.

Development of dextrin-amphotericin B formulations for the treatment of Leishmaniasis.

The most effective medicines available for the treatment of leishmaniasis, a life-threatening disease, exhibit serious toxicological issues. To achieve better therapeutic efficiency while decreasing toxicity associated with amphotericin B (AmB), water-soluble dextrin-AmB (Dex-AmB) formulations were developed. Self-assembled nanocomplexes were formed by dissolving Dex and AmB in alkaline borate buffer, followed by dialysis and either freeze-drying (FD) or nano spray-drying (SD), yielding water dispersible particles with a diameter of 214 nm and 347 nm, respectively. The very simple production process allowed the formation of amorphous inclusion complexes containing 14% of AmB in the form of monomers and water-soluble aggregates. Nanocomplexes were effective against parasites in axenic culture (IC50 of 0.056 and 0.096 µM for L. amazonensis and 0.030 and 0.044 µM for L. infantum, respectively for Dex-AmB FD and Dex-AmB SD) and in decreasing the intramacrophagic infection with L. infantum (IC50 of 0.017 and 0.023 µM, respectively for Dex-AmB FD and Dex-AmB SD). Also, the formulations were able to significantly reduce the cytotoxicity of AmB. Overall, this study demonstrates the suitability of dextrin as an AmB carrier and the facile and inexpensive development of a delivery system for the treatment of leishmaniasis.

Sleep quality and memory function in healthy ageing. / Calidad del sueño y déficit de memoria en el envejecimiento sano.

OBJECTIVE: To study the relationship between sleep quality and memory in healthy ageing. METHODS: The study included 99 people older than 50 years (69 women and 30 men; mean age, 68.74±7.18 years) with no associated diseases. Patients completed digital versions of the Word Learning and Visual Paired Associates tests and the Pittsburgh Sleep Quality Index questionnaire to assess the quality of sleep. RESULTS: Pittsburgh Sleep Quality Index score was negatively correlated with Visual Paired Associates and Word Learning test performance. Performance in these 2 memory tests decreased in line with sleep quality. In addition, performance in Visual Paired Associates test was negatively correlated with subjective sleep quality, duration, and sleep disturbances. Performance on the Word Learning test was negatively correlated with subjective sleep quality and efficiency. Participants' sex showed a weak effect on Visual Paired Associates performance and sleep latency. CONCLUSIONS: Medical professionals working with elderly patients should take into consideration the effect of poor sleep quality on memory. Cognitive impairment in these patients may be a manifestation of a neuroendocrine imbalance due to a disrupted circadian rhythm. More research is needed to prove this hypothesis.

An examination of trends in amount and type of cigarette advertising and sales promotions in California stores, 2002-2005.

BACKGROUND: Cigarette companies spend more of their marketing dollars in stores than in any other venue. In 2005, they spent 88% of a total of $13.1 billion to advertise and promote product sales in stores. AIM: The purposes of this study were to identify how the amount and types of cigarette advertising and sales promotions have changed in stores in California between 2002 and 2005, and to assess neighbourhood influences on cigarette marketing in stores. METHODS: Four observational assessments of cigarette advertising were conducted in approximately 600 California stores that sold cigarettes from 2002 to 2005. Trained observers collected data on the amount and type of cigarette advertising, including signs, product shelving and displays and functional items, and presence of sales promotions on these items. Longitudinal analyses were performed to estimate trends over time and identify correlates of change in the amount and type of tobacco advertising. RESULTS: The mean number of cigarette advertisements per store increased over time from 22.7 to 24.9. The percentage of stores with at least one advert for a sales promotion increased from 68% to 80%. The amount of advertising and proportion of stores with sales promotions increased more rapidly in stores situated in neighbourhoods with a higher proportion of African-Americans. CONCLUSION: The results indicate increasing use of stores to market and promote cigarette sales. Further, these increases are disproportionately accelerating in neighbourhoods with more African-Americans. Legislative strategies should be pursued to control the marketing of tobacco products and promotional strategies used to reduce prices in stores.

Diagnosis and management of hyperprolactinemia: results of a Brazilian multicenter study with 1234 patients.

OBJECTIVE: The aim of the study was to evaluate clinical and laboratorial features of 1234 patients with different etiologies of hyperprolactinemia, as well as the response of 388 patients with prolactinomas to dopamine agonists. DESIGN, SETTING, AND PATIENTS: A total of 1234 hyperprolactinemic patients from 10 Brazilian endocrine centers were enrolled in this retrospective study. MAIN OUTCOME MEASURE: PRL measurement, thyroid function tests, and screening for macroprolactin were conducted. RESULTS: Patients were subdivided as follows: 56.2% had prolactinomas, 14.5% drug-induced hyperprolactinemia, 9.3% macroprolactinemia, 6.6% non-functioning pituitary adenomas, 6.3% primary hypothyroidism, 3.6% idiopathic hyperprolactinemia, and 3.2% acromegaly. Clinical manifestations were similar irrespective of the etiology of the hyperprolactinemia. The highest PRL levels were observed in patients with prolactinomas but there was a great overlap in PRL values between all groups. However, PRL>500 ng/ml allowed a clear distinction between prolactinomas and the other etiologies. Cabergoline (CAB) was more effective than bromocriptine (BCR) in normalizing PRL levels (81.9% vs 67.1%, p<0.0001) and in inducing significant tumor shrinkage and complete disappearance of tumor mass. Drug resistance was observed in 10% of patients treated with CAB and in 18.4% of those that used BCR (p=0.0006). Side-effects and intolerance were also more common in BCR treated patients. CONCLUSION: Prolactinomas, drug induced hyperprolactinemia, and macroprolactinemia were the 3 most common causes of hyperprolactinemia. Although PRL levels could not reliably define the etiology of hyperprolactinemia, PRL values >500 ng/ml were exclusively seen in patients with prolactinomas. CAB was significantly more effective than BCR in terms of prolactin normalization, tumor shrinkage, and tolerability.

Detection of nosocomial malnutrition is improved in Amazon region by a standard clinical nutrition education program.

BACKGROUND: In Brazil hospital malnutrition is highly prevalent, physician awareness of malnutrition is low, and nutrition therapy is underprescribed. One alternative to approach this problem is to educate health care providers in clinical nutrition. The present study aims to evaluate the effect of an intensive education course given to health care professionals and students on the diagnosis ability concerning to hospital malnutrition. MATERIALS AND METHODS: An intervention study, based on a clinical nutrition educational program, offered to medical and nursing students and professionals, was held in a hospital of the Amazon region. Participants were evaluated through improvement of diagnostic ability, according to agreement of malnutrition diagnosis using Subjective Global Assessment before and after the workshop, as compared to independent evaluations (Kappa Index, k). To evaluate the impact of the educational intervention on the hospital malnutrition diagnosis, medical records were reviewed for documentation of parameters associated with nutritional status of in-patients. The SPSS statistical software package was used for data analysis. RESULTS: A total of 165 participants concluded the program. The majority (76.4%) were medical and nursing students. Malnutrition diagnosis improved after the course (before k = 0.5; after k = 0.64; p < 0.05). A reduction of false negatives from 50% to 33.3% was observed. During the course, concern of nutritional diagnosis was increased (chi2 = 17.57; p < 0.001) and even after the course, improvement on the height measurement was detected (chi2 = 12.87; p < 0.001). CONCLUSIONS: Clinical nutrition education improved the ability of diagnosing malnutrition; however the primary impact was on medical and nursing students. To sustain diagnostic capacity a clinical nutrition program should be part of health professional curricula and be coupled with continuing education for health care providers.

Weight evolution in girls treated for idiopathic central precocious puberty with GnRH analogues.

UNLABELLED: Data concerning the effects of GnRHa on weight gain are scarce. OBJECTIVE: To assess the variation of the body mass index (BMI) in girls during GnRHa treatment for idiopathic central precocious puberty (CPP). PATIENTS AND METHODS: Semestral anthropometric data from 176 girls treated with goserelin or leuprorelin were analyzed. RESULTS: BMI z-score increased from 1.5 +/- 0.1 SD before treatment (n = 176) to 1.7 +/- 0.2 SD after 24 months (n = 61, p = 0.008). In girls with normal weight before treatment, this variation was greater (n = 112, 0.2 +/- 0.1 SD, p = 0.01) than in those who were overweight (n = 63, -0.9 +/- 0.2 SD, p = 0.7). In the goserelin group the weight change adjusted for bone age was greater (n = 28, 0.4 +/- 0.1 SD) than in the leuprorelin group (n = 5, 0.04 +/- 0.1 SD, p = 0.05). CONCLUSIONS: A slight increase in BMI was noted, mainly in girls with normal weight before treatment. The influence of different GnRHa on weight must be further investigated.

Identification of the major sites of enzymic glycosylation of myelin basic protein.

In the presence of porcine submaxillary N-acetylgalactosaminyltransferase and uridine diphospho-N-acetyl-D-galactosamine, approx. 1.2-1.5 mol of N-acetylgalactosamine were transfered per mol of myelin basic protein. Tritium-labelled N-acetylgalactosamine-labelled basic protein was digested with trypsin and the peptides were separated by HPLC and the radioactivity measured. Most of the radioactivity was associated with three peptide peaks (I, II and III) containing 17, 69 and 6% of the total radioactivity, respectively. The remaining radioactivity was distributed amongst several peptides, each containing less than 2.5% of the total radioactivity. Glycosylation of the basic proteins isolated from human, bovine and guinea pig myelins showed that they were all equally good acceptors. In spite of differences in the peptide profiles of the basic proteins from different species, the distribution of radioactivity between the three peptide peaks was similar for all the species studied. The transfer of N-acetylgalactosamine to peptide II was much faster than to peptides I and III. The apparent Km values of the three peptides were within a narrow range of 0.52-0.63 mM, whereas the Vmax values were considerably different. The glycosylated peptide peaks (I, II and III) were separated by electrophoresis, the radioactivity measured, and amino acid compositions determined after hydrolysis. The major radioactive peptides of the human basic protein were identified with tryptic peptides containing the following sequences: (formula; see text)

The effects of development on activity, specificity and endogenous substrates of synaptic membrane sialidase.

Synaptic plasma membranes were prepared from cortices of rats varying in post-natal age between 4 and 30 days. Sialic acid associated with synaptic plasma membrane glycoproteins and gangliosides increased 75% and 50%, respectively, between 4 and 30 days. The amount of sialic acid released from these membrane constituents by intrinsic synaptic sialidase increased 2-4-fold over the same period. Incubation of synaptic plasma membranes with exogenous gangliosides or glycopeptides demonstrated a 2-3-fold increase in sialidase activity during development. The major gangliosides present in synaptic plasma membranes at all ages were GT1, GD1a, GD1b and GM1. Intrinsic sialidase hydrolyzed 50-70% of endogenous GT1 and GD1a gangliosides at all ages. Endogenous GD1b ganglioside was poorly hydrolyzed in young rats and its susceptibility to enzymic hydrolysis increased during development. When exogenous GD1a and GD1b were used as substrates a preferential increase in activity against GD1b occurred during development, the ratio of activity (GD1a/GD1b) decreasing from 3.6 to 1.6 between 7 and 30 days. 10- and 30-day-old synaptic plasma membranes contained complex mixtures of sialoglycoproteins, an increase in the relative concentrations of lower molecular weight sialoglycoproteins occurring during development. Intrinsic sialidase present in 10- and 30-day-old synaptic plasma membranes acted upon all molecular weight classes of sialoglycoproteins.

Interleukin 1 and phorbol 12-myristate 13-acetate induce collagenase and PGE2 production through a PKC-independent mechanism in chondrocytes.

In the present study we demonstrate that interleukin 1 (IL 1) and phorbol 12-myristate 13-acetate (PMA) stimulate collagenase production by bovine chondrocytes in monolayer culture. Since it has been well established that PMA stimulates protein kinase C (PKC), we examined whether IL 1 and PMA also stimulate PKC in chondrocytes. In agreement with other studies, PMA induced the translocation of PKC, reflecting PKC activation by PMA. In contrast, IL 1 did not induce the translocation of PKC. Both IL 1 and PMA stimulated the release of [14C]arachidonic acid from chondrocyte phospholipids, suggesting that both agents stimulate phospholipase A2 (PLA2). Concomitantly, IL 1 and PMA also induced a pronounced increase in the production of PGE2. Pre-incubation of chondrocytes with staurosporine, a PKC inhibitor, did not affect the stimulation of collagenase production by IL 1 and only minimally that induced by PMA. Similarly, high concentrations of staurosporine did not inhibit prostaglandin E2 (PGE2) production induced by IL 1 or PMA. These data show that IL 1 and PMA stimulate the PLA2 pathway and collagenase production, however, these processes can occur in the absence of PKC activation.

Fetal bovine serum inhibits chondrocyte collagenase production: interleukin 1 reverses this effect.

Bovine articular chondrocytes incubated in medium which was serum free or contained low levels of fetal bovine serum (less than 5%) constitutively produced collagenase. Increasing the concentration of serum in the culture medium inhibited the production of collagenase. Addition of interleukin 1 and lipopolysaccharide reversed the inhibitory effect of serum. Phorbol esters only stimulated collagenase production when the serum concentration was at least 10%. These data suggest that there is a factor(s) in fetal bovine serum that inhibits collagenase production by chondrocytes and this can be reversed by agents such as interleukin 1.

The effect of magnesium supplementation in increasing doses on the control of type 2 diabetes.

OBJECTIVE: Hypomagnesemia occurs in 25-38% of patients with type 2 diabetes. Several studies have suggested an association between magnesium (Mg) depletion and insulin resistance and/or reduction of insulin secretion in these cases. Our purpose was to evaluate if Mg supplementation (as magnesium oxide [MgO]) would improve metabolic control in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 128 patients with type 2 diabetes (32 men, 96 women, aged 30-69 years), treated by diet or diet plus oral antidiabetic drugs, in the Bahia Federal University Hospital, Brazil. Patients at risk for hypomagnesemia or with reduced renal function were excluded. This study was a clinical randomized double-blind placebo-controlled trial. Patients received either placebo, 20.7 mmol MgO, or 41.4 mmol MgO daily (elementary Mg) for 30 days. Mg concentrations were measured in plasma, in mononuclear cells, and in 24-h urine samples. Fasting blood glucose, HbA1, and fructosamine were used as parameters of metabolic control. RESULTS: Of the patients, 47.7% had low plasma Mg, and 31.1% had low intramononuclear Mg levels. Intracellular Mg in patients with diabetes was significantly lower than in the normal population (62 blood donors; 1.4 +/- 0.6 vs. 1.7 +/- 0.6 micrograms/mg of total proteins). No correlation was found between plasma and intracellular Mg concentrations (r = -0.179; P = 0.15) or between Mg concentrations and glycemic control (r = -0.165; P = 0.12). Intracellular Mg levels were lower in patients with peripheral neuropathy than in those without (1.2 +/- 0.5 vs. 1.5 +/- 0.6 micrograms/mg). Similar findings were observed in patients with coronary disease (1.0 +/- 0.5 vs. 1.5 +/- 0.6 micrograms/mg). In the placebo and in the 20.7 mmol Mg groups, neither a change in plasma and intracellular levels nor an improvement in glycemic control were observed. Replacement with 41.4 mmol Mg tended to increase plasma, cellular, and urine Mg and caused a significant fall (4.1 +/- 0.8 to 3.8 +/- 0.7 mmol/l) in fructosamine (normal, 1.87-2.87 mmol/l). CONCLUSIONS: Mg depletion is common in poorly controlled patients with type 2 diabetes, especially in those with neuropathy or coronary disease. More prolonged use of Mg in doses that are higher than usual is needed to establish its routine or selective administration in patients with type 2 diabetes to improve control or prevent chronic complications.