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At least 1,207 records · Page 67Linked to original sources
PubMed2002

Is type 2 diabetes a chronic inflammatory/autoimmune disease?

The classification of diabetes mellitus into 2 main types, defined as Type 1 and 2 diabetes (T1DM, T2DM) relies mostly on the requirement of insulin therapy and on the presence of detectable immunologic abnormalities. However, this distinction is far from straightforward and there is considerable overlap between these 2 types of diabetes. Islet cell autoimmunity, which is characteristic of T1DM, appears in fact to be present in up to 10-15% of subjects diagnosed clinically with T2DM. In the UK Prospective Diabetes Study (UKPDS), it was reported that in patients diagnosed with in T2DM, the presence of autoantibodies to the enzyme glutamic acid decarboxylase (GAD) and cytoplasmic islet cell antibodies (ICA) were a predictor of insulin requirement as compared with patients not carrying these autoantibodies. These results are strikingly similar to a number of prospective studies carried out in childhood diabetes. If islet cell autoimmunity is truly present in 10-15% of subjects clinically diagnosed with T2DM, up to two million Americans might have an unidentified autoimmune form of T2DM, a prevalence similar to that of recent onset childhood diabetes. In addition, we found that in a subset of T2DM patients, a pronounced activation of the acute phase response that seems to be associated with islet cell autoimmunity. These results may in part explain the defect in insulin secretion as well as insulin resistance seen in T2DM. The identification of a subgroup of individuals at risk of developing T2DM using autoantibody as well as inflammatory markers is of public health interest, not only for the correct classification of diabetes, but also because immunomodulatory therapeutic strategies could potentially be instituted sufficiently early in a large number of patients diagnosed as having T2DM and most likely delay the onset of insulin requirement and the complications related with hyperglycemia.

Acute-Phase Reaction↗
PubMedDate not supplied

[The pathological mechanisms of glycoregulation disturbances in chronic hepatitis B and C].

Despite the abundance of reports concerning the increased frequency of diabetes and impaired glucose tolerance in chronic liver diseases, the mechanisms underlying this phenomenon have not been resolved. 30 patients with hepatitis C virus (HCV) infection and 17 with hepatitis B virus (HBV) infection who showed an altered responds to a standard oral glucose tolerance test were investigated in order to evaluate their pancreatic-endocrine features. We have also evaluated 40 patients (20 with HCV infection and 20 with HCB infection) who developed diabetes after diagnosis of liver disease. Patients with HBV infection showed signs of enhanced insulin resistance but overt diabetes develops in those who, in addition to insulin insensitivity, have a relative defect of insulin secretion. In patients with HCV infection the significantly lower plasma insulin and C-peptide levels suggest that impairment of insulin secretion is the main mechanism leading to both glucose intolerance and overt diabetes.

Blood Glucose↗
PubMedDate not supplied

[Mature onset diabetes of the young (MODY)].

Maturity-onset diabetes of the young (MODY) is a rare form of juvenile diabetes mellitus, defined by early onset, absence of ketosis, non-insulin-dependent diabetes and autosomal dominant inheritance. Advances in molecular genetic analysis have identified mutations accounting for different MODY subtypes, all of them associated with defects of insulin secretion. We present a case of a nine year-old boy, admitted to our outpatient clinic because of mild and intermittent osmotic symptoms (polyuria, polyphagia and polydipsia) and persistently high values of fasting blood glucose in the last year. He had a family history of diabetes in three consecutive generations compatible with autossomal dominant inheritance. His height was 138.5 cm (90th centile) and his weight was 33.5 Kg (90th centile). General examination was unremarkable, in a prepubertal boy. A standard oral glucose tolerance test was performed. The fasting blood glucose was 118 mg/dl with a two hour value of 160 mg/dl. ICA, IAA and GAD autoantibodies were undetectable. He started on diet therapy, keeping his fasting blood glucose measurements on the upper limits of normal and HbA1c in the normal range. He was diagnosed as having MODY 2 on a clinical basis, as it is not possible to perform molecular analysis of this pathology in Portugal. As MODY is recently thought to account for 2-5% of all cases of type 2 Diabetes Mellitus it is important to consider it as a possible diagnosis in children who present with incidental hyperglycaemia. Molecular genetic testing is very important as it enables us to make a firm diagnosis of MODY, to define a follow up plan and to reassure patients families, once the prognosis is significantly different among the different sub-types of MODY. We emphathize the need of creating national and international reference centres where such testing can be done.

Blood Glucose↗
PubMed2003

Congenital adrenal hyperplasia: biochemical and molecular perspectives.

Congenital adrenal hyperplasia is a disorder occurring in both sexes and is the commonest cause of ambiguous genitalia. It is a group of autosomal recessive disorders in which, on the basis of an enzyme defect the bulk of steroid hormone production by adrenal cortex shifts from corticosteroids to androgens. Autosomal recessive mutations in the CYP21, CYP17, CYP11B1 and 3betaHSD genes that encode steroidogenic enzymes, in addition to mutations in the gene encoding the intracellular cholesterol transport protein steroidogenic acute regulatory protein StAR can cause CAH. Each of the defects causes different biochemical consequences and clinical features. Deficiencies in 21 hydroxylase (21-OH) and 11beta-Hydroxylase (11beta-OH) are the two most frequent causes of CAH. All the biochemical defects impair cortisol secretion, resulting into compensatory hypersecretion of ACTH and consequent hyperplasia of the adrenal cortex. Research in recent years has clarified clinical, biochemical and genetic problems in diagnosis and treatment of the disorders. Expanding knowledge of the gene mutations associated with each of these disorders is providing valuable diagnostic tools in addition to the biochemical profile and phenotype. Genotyping is useful in selecting instances to provide genetic counseling and to clarify ambiguous cases.

Adrenal Hyperplasia, Congenital↗
PubMed1992

[Hyperkalemia in a cyclosporine A-treated allogeneic bone marrow transplant recipient].

A 9-year-old boy was admitted with the diagnosis of myelodysplastic syndrome (FAB RAEB in T). The patient was treated with busulfan and cyclophosphamide and transplanted with bone marrow cells from an HLA identical sister. Cyclosporin A (CyA) and short term methotrexate (MTX) was given for prophylaxis against graft versus host disease (GvHD). The serum potassium value was observed to increase to 6.3 mEq/l during the period of CyA therapy. The serum potassium value returned to 4 mEq/l when CyA treatment was decreased to a serum concentration of less than 50 ng/ml (FPIA). On day 90 post transplantation the patient was diagnosed as relapsed. The patient was preconditioned with cyclophosphamide and total body irradiation and a second bone marrow transplantation was performed using cells from the same donor. He was treated again with CyA and short term MTX for the prevention of GvHD. Once again the patient became hyperkalemic with 6.8 mEq/l. The serum creatinine level was 0.9 mg/dl, the GFR was 52.1 ml/min, FEK was 7.1%. Pseudohypoaldosteronism or hyporeninemic hypoaldosteronism was suspected. To investigate this possibility a renin/aldosterone stimulation test was performed. We speculate that an idiosyncratic response to CyA resulted in pseudohypoaldosteronism and produced a defect in potassium secretion.

Bone Marrow Transplantation↗
PubMed2004

Epidemiology of type 1 Diabetes Mellitus.

Type 1 diabetes can be diagnosed at any age, but dinical course, genetic, and environmental determinants appear to be heterogenous by age. The common pathway begins with preclinical beta-cell autoimmunity with progressive defect of insulin secretion, followed by onset of hyperglycemia, transient usually partial remission, and finally complete insulinopenia associated with acute and chronic complications and premature death. Current research effort is focused on identification of the genetic and environmental determinants of this process and the ways they interact.

Adolescent↗
PubMedDate not supplied

[Towards a tripple oral therapy in the pharmacological treatment of type 2 diabetes?].

Type 2 diabetes is a complex disease combining several disturbances in various organs, especially a defect of insulin secretion by the pancreas, an increased production of glucose by the liver and a reduced insulin-mediated glucose uptake by the skeletal muscle. Each of these abnormalities can be, at least partially, reversed by a specific pharmacological approach, an agent promoting insulin secretion (sulphonylurea, glinide), metformin and a thiazolidinedione (glitazone), respectively. A triple oral therapy with "sulphonylurea (glinide)--metformin--glitazone", targeting simultaneously the three main metabolic abnormalities of type 2 diabetes, deserves special attention. Promising results have been observed in recent clinical trials as far as blood glucose control and some other cardiovascular risk factors are concerned. The precise place of such oral triple therapy remains to be specified, at a late stage to delay the shift to insulin or earlier in the natural history of the disease, to avoid the decline of the number and/or function of beta cells and the resulting metabolic deterioration.

Blood Glucose↗
PubMed1992

[A case of hyporeninemic hypoaldosteronism improved by dexamethasone treatment].

A 76-year-old man was admitted because of general fatigue and lumbago. Two years before admission, hyponatremia and hyperkalemia were pointed out, subsequently hydrocortisone (20 mg/day) was given under the diagnosis of panhypopituitarism. The marked improvement was found in the electrolytes abnormality. On examination at admission, there was no abnormality of anterior pituitary function. In addition to the extremely low level of plasma renin activity and aldosterone concentration, the persistent microhematuria and hyperuricemia were found, however, renal histology only showed the benign arteriosclerosis but no significant alteration in juxtaglomerular apparatus and glomeruli. The urinary prostacyclin metabolite output was rather increased compared to that of normal subject, suggesting that prostaglandins may not be responsible for the defect of renin secretion. Although, the cause was still unknown, small dose of dexamethasone was extremely effective to resolve electrolytes abnormality and hematuria.

Aged↗
PubMed2005

[Triple oral therapy in type 2 diabetes].

Type 2 diabetes has a complex pathophysiology, combining a defect of insulin secretion by the pancreas, an increased glucose production by the liver and a reduced insulin-mediated glucose uptake by the skeletal muscle. Each of these abnormalities can be partially reversed by a specific drug, an agent promoting insulin secretion (sulphonylurea or glinide), metformin and a thiazolidinedione (glitazone), respectively. Therefore, a triple oral therapy, targeting simultaneously the three main metabolic abnormalities of type 2 diabetes, deserves special attention. Recent clinical trials have shown both the efficacy and safety of this triple oral therapy. However, its precise place remains to be better specified in the overall management of type 2 diabetes.

Administration, Oral↗
PubMed1991

Non-insulin-dependent (type II) diabetes mellitus.

Non-insulin-dependent (type II) diabetes mellitus is an inherited metabolic disorder characterized by hyperglycemia with resistance to ketosis. The onset is usually after age 40 years. Patients are variably symptomatic and frequently obese, hyperlipidemic and hypertensive. Clinical, pathological and biochemical evidence suggests that the disease is caused by a combined defect of insulin secretion and insulin resistance. Goals in the treatment of hyperglycemia, dyslipidemia and hypertension should be appropriate to the patient's age, the status of diabetic complications and the safety of the regimen. Nonpharmacologic management includes meal planning to achieve a suitable weight, such that carbohydrates supply 50% to 60% of the daily energy intake, with limitation of saturated fats, cholesterol and salt when indicated, and physical activity appropriate to the patient's age and cardiovascular status. Follow-up should include regular visits with the physician, access to diabetes education, self-monitoring of the blood or urine glucose level and laboratory-based measurement of the plasma levels of glucose and glycated hemoglobin. If unacceptably high plasma glucose levels (e.g., 8 mmol/L or more before meals) persist the use of orally given hypoglycemic agents (a sulfonylurea agent or metformin or both) is indicated. Temporary insulin therapy may be needed during intercurrent illness, surgery or pregnancy. Long-term insulin therapy is recommended in patients with continuing symptoms or hyperglycemia despite treatment with diet modification and orally given hypoglycemic agents. The risk of pancreatitis may be reduced by treating severe hypertriglyceridemia (fasting serum level greater than 10 mmol/L) and atherosclerotic disease through dietary and, if necessary, pharmacologic management of dyslipidemia. Antihypertensive agents are available that have fewer adverse metabolic effects than thiazides and beta-adrenergic receptor blockers. New drugs are being developed that will enhance effective insulin secretion and action and inhibit the progress of complications.

Diabetes Mellitus, Type 2↗
PubMed1991

Effects of cranial irradiation on hypothalamic-pituitary function--a 5-year longitudinal study in patients with nasopharyngeal carcinoma.

The effects of cranial irradiation on hypothalamic-pituitary function were studied over a 5-year period in 31 adult patients with nasopharyngeal carcinoma. The estimated radiotherapy doses to the hypothalamus and pituitary were 3979 +/- 78 (+/- SD) and 6167 +/- 122 cGy, respectively. Within 2 years of radiotherapy, significant impairment in the secretion of growth hormone, gonadotrophins, corticotrophin and thyrotrophin were evident and 14 per cent of patients developed hyperprolactinaemia. Using life table analysis, the cumulative probability of endocrine dysfunction was estimated to be 62 per cent after 5 years with deficiencies in growth hormone, gonadotrophins, corticotrophin and thyrotrophin found in 63.5, 30.7, 26.7 and 14.9 per cent of patients, respectively. Growth hormone deficiency was the earliest endocrine dysfunction observed. Hyperprolactinaemia was uncommon in the male patients but occurred in five of eight women within 3 years of cranial irradiation. The alterations in gonadotrophin secretion suggest a defect in the pulsatile release of gonadotrophin releasing hormone. Twenty-eight patients developed a hypothalamic pattern of delayed thyrotrophin response to thyrotrophin releasing hormone one year after radiotherapy--four subsequently became hypothyroid. Patients who received radiotherapy for cervical lymph nodes were at greater risk of developing hypothyroidism. Thus, in these patients with no pre-existing disease in the hypothalamic-pituitary region, progressive impairment in hypothalamic pituitary function leading to endocrine dysfunction requiring treatment occurs in 50 per cent of patients 5 years after cranial irradiation. Regular endocrine assessment should be performed in all patients following cranial irradiation.

Adrenocorticotropic Hormone↗
PubMed1990

[Evaluation after 2 years of substitutive treatment of PiZZ emphysema with alpha-1 antitrypsin. 9 cases].

Homozygous PiZZ individuals with a serum deficiency due to a defect in the secretion of the alpha 1-antitrypsin protein are at risk of developing severe panlobular emphysema. Tobacco smokers are particularly exposed to the disease which begins at an earlier age. Treatment by substitutive therapy with alpha 1-antitrypsin concentrates seems to be the only possibility. A two years' clinical trial was performed in 9 PiZZ patients, with more than 1,500 infusions being administered weekly. Serum AAT levels were used as guidelines to follow biochemical changes in the protease-antiprotease balance. From 0.16 g/l initially, the AAT level rose to 0.57 g/l after 7 months. No adverse reaction was observed during the trial; the concentrated protein was well accepted, ant the antielastase activity of the protein recovered after injection was equivalent to the activity injected. An attempt to administer the infusions monthly was stopped when we observed a dramatic decrease of the serum AAT level. Clinically, stabilization of the symptoms was noted. No degradation was observed in the patients who took part in the trial, even if no real improvement was detected.

Adult↗
PubMed1990

[Male-female transsexualization with glandular preservation].

The choice of the tissue to build up the neovagina is an important step in the surgical treatment of transsexualism. Both the penile skin and an intestinal segment are possible solutions to the problem. However intestinal segments have some defects like continuous secretions and painful intercourse. For these reasons the authors prefer the penile skin with the neuro-vascular bundle preserved. One hundred cases of this surgery are presented.

Female↗
PubMedDate not supplied

Cystic fibrosis: a current review.

Cystic fibrosis (CF) is the most common severe genetic disorder seen in Caucasians. Defective exocrine gland secretions result in chronic diseases of the respiratory and gastrointestinal systems. However, the CF gene recently has been located and cloned. Currently, genetic technology allows identification of sibling carriers and antenatal diagnosis within families. Oral implications associated with CF include enamel hypoplasia and tooth discoloration, salivary gland involvement, reduced incidence of dental caries, reservoir for potentially pathogenic respiratory bacteria, mouth breathing, and anterior open bite associated with nasal and sinus obstruction. Continued efforts to improve early diagnosis and treatment of CF should increase life expectancy. Affected patients are expected to seek regular dental care more frequently as they learn to view the disease as manageable.

Cystic Fibrosis↗
PubMed1989

Postnatal development of photoreceptor proteins in mutant mice and Abyssinian cats with retinal degeneration.

Using immunocytochemical techniques, development of opsin, transducin alpha and S-antigen in photoreceptor cells of the mice homozygous or heterozygous for the rd or rds genes has been found to be similar to that of control animals during the first postnatal week. Even though the absolute amounts of these proteins are low (eg. opsin in the rds retina) or decrease in the postnatal period (as in the rd retina), we can demonstrate their persistence during the entire degeneration process. In fact, the content of the proteins in the photoreceptor perikarya actually appear to be higher after postnatal day 11 in all mutants studied. Thus, one of the major manifestations of the mutant retinae is a loss of polarity of the photoreceptor cells at the time of ROS degeneration without a loss in the ability to synthesize these important proteins of the visual cycle. This correlates well with the apparent defect in IRBP secretion and its intracellular accumulation in mutant photoreceptor cells as previously observed (van Veen et al. 1986). In the Abyssinian cat model for progressive retinal atrophy, the development an cellular distribution of all the proteins studied are similar in affected and control retinae until the beginning of stage 2 of the disease. At this time, outer segments begin to degenerate and immunoreactivity increases in the photoreceptor perikarya. The IRBP content of the retina declines markedly at stage 2, preceding extensive loss of photoreceptors.

Aging↗
PubMedDate not supplied

[Transverse testicular ectopy with common deferent duct].

Transverse testicular ectopia is a malfunction of which there are 65 cases described in the Western literature. The pathogeny is unknown, although in the cases in which it is associated with persistence of Mullerian residue, it is attributed to a defect in the secretion of MIF (Mullerian inhibiting factor). In the other cases the fundamental cause is considered to stem from alterations in the vascularization of the genital crest, which determines the type of testicular ectopia. We present a case of crossed testicular ectopia with common deferent duct in a three-year-old male, treated by means of descent and transposition via the interscrotal septum with modified Ombrédanne's technique.

Child, Preschool↗
PubMed1989

Acute response of urine pH following ammonium chloride administration to dogs.

To test the acidifying ability of the distal portion of the nephrons in healthy dogs, 0.2 g of NH4Cl/kg of body weight was given PO. Samples for venous blood gas analysis and urine pH were taken hourly for 6 hours. Systemic acidemia developed, as evidenced by a statistically significant (P less than 0.05) decrease in blood pH 1 hour after NH4Cl administration. Four hours after administration, mean urine pH decreased to a low of 5.16 +/- 0.1 and was less than 5.5 3 hours after administration. Changes in urine pH 2 hours after administration were statistically significant (P less than 0.05). In human beings, NH4Cl loading is used to detect patients with distal renal tubular acidosis (defective hydrogen ion secretion by the distal nephrons) and normal acid/base values. Distal renal tubular acidosis is diagnosed if urine pH fails to decrease to less than 5.5 after NH4Cl administration. On the basis of the findings of this study, a similar value would be valid for dogs.

Ammonium Chloride↗
PubMed1988

DNA rearrangements affecting both variable and constant regions of Ig H chain genes in MPC11 mouse myeloma variants.

We have examined the mechanisms that account for short Ig H chain production in two variants of the mouse myeloma cell line MPC11 (IgG2b, kappa) by mRNA sequencing and restriction enzyme mapping. One variant, F5.5, has a thymidine residue inserted into the (CH3) domain, of the Ig H chain, resulting in premature termination and translation of a gamma 2b H chain of 50,000 m.w. A second variant, E5.7A12, contains gamma 2a-derived sequences that extend from near the 3' end of the CH2 domain to the intervening sequence between the CH2 and CH3 domains, consistent with a microrecombination event (defined as either a double cross-over or gene conversion event). In this variant, the 5' end of the CH3 domain has been deleted, but the remainder of the gamma 2b(CH3) domain is present, resulting in the translation of a gamma 2b-gamma 2a-gamma 2b H chain of 52,000 m.w. Additional rearrangements affecting sequences in or adjacent to the variable region accompany H chain constant region alterations in these cell lines and subclones of these cell lines. In F5.5, novel sequences have recombined within one of two duplicated copies of the VH gene. In a sister clone of E5.7A12 that has ceased H chain production (E5.7A14), new sequences have recombined within 300 bp 5' of the enhancer element. Both F5.5 and E5.7A12, like their immediate unstable precursor cells, fail to assemble H-H dimers, halting the Ig assembly process at the heavy-light stage, and do not secrete H chains. We speculate that defects in H chain assembly and secretion, as exemplified by the parents of these variants (i.e., intermediates of these secondary variants), reactivate the Ig gene rearrangement machinery and result in the formation of these putatively equally unstable secondary variants.

Amino Acid Sequence↗