Effect of parathyroidectomy for primary hyperparathyroidism on bone mineral density in postmenopausal women

Background

The bone mineral density (BMD) response to parathyroidectomy is heterogeneous and difficult to predict. Available data come from mixed populations of men and women, of different age and degrees of disease severity, and preoperative BMD loss.

Methods

This was a longitudinal, prospective cohort study of 103 postmenopausal women with osteopenia or osteoporosis at the femoral neck site, successfully operated on for primary hyper parathyroidism. BMD and metabolic variables were recorded before and 1 year after parathyroidectomy.

Results

After surgery, there was a 1·3 per cent increase in the median BMD at the femoral neck site (0·615 versus 0·623 g/cm2; P = 0·001). Overall, positive responses were also observed at total hip (0·4 per cent) and lumbar spine (2·3 per cent) sites. Analysing the individual responses, however, only 45 (46 per cent) of 97 patients showed a significant (at least 3·7 per cent) increase in BMD at the femoral neck site compared with the preoperative value and 52 had a decreased (15) or unchanged (37) femoral neck BMD. Patients who gained BMD were younger, had more severe hyperparathyroidism and better renal function.

Conclusion

Almost half of the postmenopausal women with hyperparathyroidism and low BMD have a significant remineralization response 1 year after parathyroidectomy. Differential mineralization responses of BMD after surgery appear to be related to severity of primary hyperparathyroidism, age and renal function.

Genotype and phenotype correlations in diabetic patients in Uruguay

To differentiate among different types of diabetes is becoming an increasingly challenging task. We investigated whether the patient's genetic profile is useful to identify the particular type of diabetes, to determine the corresponding hyperglycemia pathogenesis and treat accordingly. Three hundred and thirty-eight diabetic patients, diagnosed according to American Diabetes Association criteria, were recruited from 2004 to 2008 in diabetes health reference centers. We analyzed the major gene for type 1 diabetes susceptibility (HLA DQ/DR). In order to improve our understanding of the pathogenesis of the resulting hyperglycemia and to implement a more adequate treatment for the patients, we reclassified our sample according to the presence or absence of the genetic markers. We found that a higher percentage of people than expected have immunological disease, independent of their phenotype, with a relative risk of 4.62 (95% confidence interval). This methodology allowed us to establish an association between the genotype and its resulting phenotype. We found significant differences; the phenotypic classification did not reflect immunological disease based on genotype. Moreover, when we examined markers, body mass index and age of onset, we found that many people have an intermediate phenotype between type 1 and type 2. This genetic data can help provide an accurate definition of the disease and would therefore provide the physician a better possibility of providing adequate treatment.

[Neurolymphomatosis: diagnosis of extension and assessment of response to treatment with PET-CT]

Neurolymphomatosis is a rare neurological manifestation of non-Hodgkin's lymphoma (NHL) and it may be its first and sole manifestation. Diagnosis is often difficult and nerve biopsy is generally required. However, this it is not always possible to perform or is not conclusive. We present the case of a 66-year-old woman diagnosed with giant B-cell NHL. After 6 cycles of chemotherapy, imaging and molecular biology techniques showed complete remission. At four months after treatment, the patient complained of low back pain of radicular distribution. CT and MRI imaging showed signs of lymphoproliferative activity of L5 and also lesions to thoracic nerve roots. A PET-CT was requested in order to complete the diagnosis and plan the treatment. Imaging confirmed the presence of tumor recurrence with neurolymphomatosis and also indicated lesions on the chest and abdominal level. Thus, it was decided to start a new line of chemotherapy, without performing the histological study through biopsy. This case illustrates the important role played by PET-CT imaging in neurolymphomatosis diagnosis. This technique can help the patient avoid more aggressive procedures, such as a biopsy, and can also be useful in the follow-up and assessment of the treatment response to NHL-diagnosed patients.

[Renal dynamics: comparison between diuretic renogram and magnetic resonance imaging]

OBJECTIVE

This study aimed to establish a comparison between the data obtained in the renal functional study through magnetic resonance using gadolinium with diuretic (furosemide) charge (MR-Gd/F), on the one hand, and the parameters obtained with the classical diuretic renogram (DR) (differential renal function -DRF- and renographic curve -RC-), on the other hand.

MATERIAL AND METHOD

10 patients were studied, 6 male and 4 female, aged between 1 month and 6 year-old. All the patients were submitted to a MR-Gd/F and a DR. In both cases, furosemide was used as overload. The pathologies observed included syndrome of the pyeloureteral junction, polar vessel, ureter valve, ectopic ureter, duplex kidney, renal dysplasia, renal ectasy, pelvic kidney and horseshoe kidney. The percentage of gadolinium uptake was compared versus the DRF, and the MR curve was compared versus the RC. Surgical treatment was required in 5 cases and an expectancy behaviour was taken in 3 cases. Among the operated patients, the diagnosis accurry was confirmed by the surgery and the pathological study.

RESULTS

A 80% consistency was found between the gadolinium uptake and the DRF. There was a 90% correlation between the MR-Gd/F curve and the RC. In two cases, the MR-Gd/F required to modify the surgical criterion -previously based on the DR- and an expectancy behaviour was taken. In 90% of the operated cases, the diagnostic assumption obtained through the MR-Gd/F coincided with the surgical and pathological findings, whereas there was a coincidence in just 60% of the cases studied through the DR (p > 0.0008).

CONCLUSIONS

The MR offers a real time study: anatomical, vascular and functional. Good correlation between DR and MR with respect to: (% DRF,%Gd MR and diuretic curve). The MR demonstrates greater precision in diagnosis.The MR allows recognition of non obstructive polar vessels that can then be conservatively managed.

Long-term melatonin administration protects brain mitochondria from aging

We tested whether chronic melatonin administration in the drinking water would reduce the brain mitochondrial impairment that accompanies aging. Brain mitochondria from male and female senescent prone (SAMP8) mice at 5 and 10 months of age were studied. Mitochondrial oxidative stress was determined by measuring the levels of lipid peroxidation and nitrite, glutathione/glutathione disulfide ratio, and glutathione peroxidase and glutathione reductase activities. Electron transport chain activity and oxidative phosphorylation capability of mitochondria were also determined by measuring the activity of the respiratory chain complexes and the ATP content. The results support a significant age-dependent mitochondrial dysfunction with a diminished efficiency of the electron transport chain and reduced ATP production, accompanied by an increased oxidative/nitrosative stress. Melatonin administration between 1 and 10 months of age completely prevented the mitochondrial impairment, maintaining or even increasing ATP production. There were no major age-dependent differences between males in females, although female mice seemed to be somewhat more sensitive to melatonin treatment than males. Thus, melatonin administration as a single therapy maintained fully functioning brain mitochondria during aging, a finding with important consequences in the pathophysiology of brain aging.

Eradication of an extensive outbreak in a neonatal unit caused by two sequential Klebsiella pneumoniae clones harbouring related plasmids encoding an extended-spectrum beta-lactamase

Outbreaks caused by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae are difficult to control and closure of an affected unit is sometimes necessary. We describe an outbreak of ESBL-producing K. pneumoniae in a 28-bed neonatal unit that began in August 2005 and lasted for seven months. Weekly rectal swabs were taken from all babies admitted throughout the study period. Review of all procedures, contact precautions, thorough environmental cleaning and restriction of cephalosporin use were implemented. ESBL production was investigated according to CLSI recommendations, and characterised by isoelectric focusing and sequencing. Typing of isolates was assessed by pulsed-field gel electrophoresis. Plasmids were also studied. During the outbreak, 32% of 503 admitted babies became colonised and nine babies developed bacteraemia; all the babies recovered. The outbreak was finally terminated in February 2006. Two distinct clones were observed, the first circulating between August and October 2005, and the second between October 2005 and February 2006. Both of these clones carried the non-ESBL SHV-11 and TEM-4 ESBL. Plasmids harbouring TEM-4 from both clones were similar and molecular analysis suggested horizontal dissemination of a single plasmid between the two clones.

Extracellular matrix protein expression in cerebrospinal fluid from patients with tropical spastic paraparesis associated with HTLV‐I and Creutzfeldt‐Jakob disease

The cerebrospinal fluid (CSF) is in direct contact with the extracellular space of the CNS, thus biochemical processes in the CNS could potentially be reflected in the CSF. Changes in extracellular matrix (ECM) proteins can be studied through their analysis in the CSF. ECM plays an essential role in CNS homeostasis and several proteins such as laminin (LN), fibronectin (FN), thrombospondin (TS) and heparan sulphate proteoglycan (HS, perlecan) form part of its structure. Possible changes in the levels of these proteins were investigated in two different pathologies--tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) (n=25) and Creutzfeldt-Jakob disease (CJD) (n=19)--and compared with those in a control group with or without neurological disease (n=25). CSF analyses were carried out using monoclonal or monospecific polyclonal antibodies. In comparison with the control group, it was found that TSP/HAM patients presented significantly higher levels of LN, TS and HS, while in CJD patients the levels of FN, TS and HS were increased. In CJD patients the HS level was almost double that of the TSP/HAM patients. These results suggest a distinct pattern of ECM proteins in CSF in relation to the type of neurological disease. TSP/HAM is a chronic motor disease that affects the white matter of the spinal cord, while CJD is a subacute dementia that affects cerebral neurons and their synapsis.

Anoxic-aerobic treatment of the liquid fraction of cattle manure

Cattle manure from a dairy farm was treated in order to reduce its pollution potential. The manure came from a farm with 120 cows kept in stables in a free stall barn. As pretreatment, the manure is usually filtered on the farm using a screw press separator with a 0.5 mm mesh. Approximately 70% of the total filtered volume passes through the screen, thus constituting the liquid fraction. This fraction, with a composition of around 64,500 mg COD/l, 5770 mg total-N/l and 800 mg total-P/l, was subjected to centrifugation followed by a two-step biological treatment (anoxic-aerobic) to reduce organic matter (COD), nitrogen and phosphorus compounds. Centrifugation led to the following removal efficiencies: 35% total solids, 60% COD, 75% total phosphorus and 20% total nitrogen (mainly organic nitrogen). With the subsequent anoxic-aerobic treatment, average removal efficiencies of 85% for COD, 90% for total phosphorus and 75% for total nitrogen were achieved.

Sciatic nerve conditioned medium depleted of pro-NGF modulates sodium currents and neurite outgrowth in PC12 cells

Excitability and axon/dendrite specification are the most distinctive features in the establishment of neuronal polarization. Conditioned medium from rat sciatic nerve (CM) induced a neuronal-like morphology in PC12 cells. Here we show that CM neuritogenic activity is limited to the induction of dendrites in PC12 cells. However, treatment of these cells with CM in combination with a generic inhibitor for tyrosine kinase receptors (k252a) promoted the enhancement of neurite length, development of axons and induction of sodium currents. On the other hand, specific inhibition of TrkA and p75(NTR) receptors in CM-treated cells reduced the neurite length in comparison with cells treated only with CM, although the effect over the induction of sodium currents was continuously observed. These results suggested that CM had some components that, even though are able to start the morphological cell differentiation and produce short neurites (likely acting through TrkA and p75(NTR)), can restrain further neurite extension. Depletion of pro-NGF isoforms from CM produced a similar effect as the exerted by k252a, TrkA and p75(NTR) receptor inhibitors in CM-treated cells, inducing the elicitation of sodium currents. These results suggested that the effect of CM might be mediated through pro-NGF. The difference between the results obtained with the generic inhibitor for Trk receptors and the specific inhibitors for TrkA and p75(NTR) receptors in CM-treated cells, suggested that alternative pathways could be used to regulate neurite elongation, axon specification and sodium currents in PC12 cells. These findings represent important clues to improve the understanding of the initiation of neuronal polarity.

Ouabain-insensitive, Na(+)-stimulated ATPase of several rat tissues: activity during a 24 h period

Rhythmic daily changes in the Na,K-ATPase activity have been previously described for rat kidney cortex, showing two peaks: at 0900 h and 2100 h, and two valleys: at 1500 h and 0100 h -0300 h. The oscillations in Na,K-ATPase activity are produced by an inhibitor, which binds the enzyme and is present in the rat blood plasma at valley times and absent or at very low concentrations at peak times. Since it has been demonstrated that active Na(+) extrusion from the cells of several tissues depends not only on the Na,K-ATPase but also on the ouabain-insensitive Na-ATPase, we studied the activity of this latter enzyme of several rat tissues, i.e., kidney cortex, small intestine, liver, heart and red blood cells along the day. None of these tissues showed any variation of their Na-ATPase activity along the day. Preincubation of kidney cortex homogenates obtained at 0900 h, with blood plasma drawn at 0900 h and 1500 h, did not modify the Na-ATPase activity. Our results indicate that the Na-ATPase activity does not oscillate along the day. These results are in agreement with the idea that the Na-ATPase could partially compensate the Na(+) transport affected by oscillations of the Na,K-ATPase activity.

Three-step biological process for the treatment of the liquid fraction of cattle manure

The liquid fraction of cattle manure was subjected to a biological treatment combining anoxic-anaerobic and oxic processes in order to stabilize the organic matter and reduce nitrogen and phosphorus so as to avoid problems of pollution when applying it to the land. The anoxic process was carried out at 30 degrees C in a CSTR reactor, the anaerobic process in a UASB reactor at 37 degrees C and the oxic treatment in another CSTR at 20 degrees C. The following results were obtained when working under optimum conditions (removal efficiencies in brackets): COD was reduced from 42 to 3.8 g/L (>90%); total solids from 41 to 14 (67%); total volatile solids from 22 to 7.0 (68%); total Kjeldahl nitrogen from 2.2 to 0.1 g/L (95%); NH4(-)-N from 1.10 to 0.02 g/L (98%) and Total-Phosphorus from 0.696 to 0.058 g/L (92%). Nitrates, undetected in the liquid fraction of cattle manure, were present in the final effluent as a result of nitrification. To reduce the amount of nitrates, different recirculation rates were tested. The minimum nitrate concentration achieved was 127 mg/L using a recirculation ratio of 4.

Characterization of nondiffusive transport in plasma turbulence via a novel Lagrangian method

A novel method to probe and characterize the nature of the transport of passive scalars carried out by a turbulent flow is introduced. It requires the determination of two exponents which encapsulate the statistical and correlation properties of the component of interest of the Lagrangian velocities of the flow. Numerical simulations of a magnetically confined, near-critical turbulent plasma, known to exhibit superdiffusive radial transport, are used to illustrate the method. It is shown that the method can easily detect the change in the dynamics of the radial transport that takes place after adding to the simulations a (subdominant) diffusive channel of tunable strength.

Histone deacetylase inhibitors: mechanism of action and therapeutic use in cancer

Histone deacetylases (HDACs) remove the acetyl groups of lysine residues of histone tails leading to chromatin compaction and transcriptional repression. In addition, HDACs can also influence transcription-independent events such as mitosis or deoxyribonucleic acid (DNA) repair and deacetylate nonhistone proteins involved in cell proliferation and death, altering their function. Histone deacetylase inhibitors (HDACi) constitute a promising treatment for cancer therapy due to their low toxicity. HDACi have been shown to induce differentiation, cell-cycle arrest, and apoptosis and to inhibit migration, invasion, and angiogenesis in many cancer cell lines. In addition, these compounds inhibit tumor growth in animal models and show antitumor activity in patients. HDACi alone and in combination with a variety of anticancer drugs are being tested in clinical trials, showing significant anticancer activity both in hematological and solid tumors. SAHA (vorinostat, Zolinza) was the first HDACi approved by the US Food and Drug Administration to enter the clinical oncology market for treating cutaneous T-cell lymphoma (CTCL) and is being tested for other malignancies.

Probabilistic model-based methodology for the conformational study of cyclic systems: application to copper complexes double-bridged by phosphate and related ligands

A methodology for the conformational study of cyclic systems through the statistical analysis of torsion angles is presented. It relies on a combination of different methods based on a probabilistic model which takes into account the topological symmetry of the structures. This methodology is applied to copper complexes double-bridged by phosphate and related ligands. Structures from the Cambridge Structural Database (CSD) are analyzed and the chair, boat-chair and boat conformations are identified as the most frequent conformations. The output of the methodology also provides information about distortions from the ideal conformations, the most frequent being: chair ↔ twist-chair, chair ↔ twist-boat-chair and boat ↔ twist-boat. Molecular mechanics calculations identify these distortions as energetically accessible pathways.

Evaluation of Metarhizium anisopliae (Hyphomycetes) for the control of Boophilus microplus (Acari: Ixodidae) on naturally infested cattle in the Mexican tropics

The efficacy of Metarhizium anisopliae on the control of Boophilus microplus in cattle infested naturally in the Mexican tropics was evaluated. The study was carried out on a ranch in Veracruz, Mexico. Twenty steers were randomly allocated into two groups of 10 cattle. Animals were naturally infested with B. microplus. Animals in the treated group were sprayed with M. anisopliae (strain Ma34) at a concentration of 1x10(8)conidia/ml every 15 days (four treatments). The other group remained as untreated control. Standard engorged female ticks were recorded on days 0, 1, 3, 5, 7 and 14 post-treatment. From the second application treatment (day 7) to the end of the experiment, animals in the treated group had lower tick infestation (P<0.05) with an efficacy of 40.0-91.2%. The results demonstrate the efficacy of repeated treatment with M. anisopiae (Ma34 strain) to control natural infestation of engorged female B. microplus on cattle in the Mexican tropics.

Process development for a Cuban cholera vaccine based on the attenuated strain Vibrio cholerae 638

Genetically modified Vibrio cholerae strain 638 (biotype El Tor, serotype Ogawa) has previously been shown to be immunogenic in animal models and in human trials. Our objective in the work reported herein was to describe the process development methods for the production of the 638 attenuated cholera vaccine. Cell seed bank, culture of biomass, lyophilization and final formulation were processes were developed. The results show kinetics of culture that fulfils a logistical model. The microbiological properties, colonizing capability, immunogenicity and non-toxigenicity of the final product were indistinguishable from the properties of the working seed lot. We conclude that the non-reactogenic, immunogenic and protective strain 638 is robust and can withstand the fermentation processes required for large-scale production of a vaccine.

Formulation in tablets of a cholera whole cells inactivated vaccine candidate

Licensed as well as candidate cholera vaccines available at the present requires the dose preparation (included buffer) at the moment of application. The aim of this work was to evaluate the presentation in oral tablets of an inactivated cholera vaccine to avoid that inconveniences during application. We have therefore compared inactivated cultures of Vibrio cholerae with tablets formulation vaccine. We obtained that antigenic activity (ELISA) and immunogenicity in animal model (ELISA and vibriocidal tests) of V. cholerae inactivated cell remained unaltered in the final tablet formulation. The results suggest that the oral tablet formulation could be a useful pharmaceutical form in order to produce a new and affordable cholera vaccine.