AZT inhibition of the ADP/ATP antiport in isolated rat heart mitochondria

In order to gain insight into the mechanism by which AZT affects mitochondrial metabolism in heart, leading to the ATP deficiency syndrome, the capability of AZT to affect certain mitochondrial translocators was checked in coupled mitochondria isolated from rat heart. AZT was found to strongly inhibit the ADP/ATP antiport, in a competitive manner (Ki 7 microM), as photometrically measured. Contrarily, the rate of the succinate/malate exchange via the dicarboxylate carrier, of the oxaloacetate uptake via the oxodicarboxylate carrier and of cis-aconitate uptake via the tricarboxylate carrier was found to be unchanged in the presence of AZT.     

Successive synovial Mycoplasma hominis isolates exhibit apparent antigenic variation.

The expression of surface proteins by 14 successive Mycoplasma hominis isolates obtained from the synovial fluid of a chronically infected septic arthritis patient was examined. Marked differences in the expression of surface proteins, as determined by monoclonal antibodies raised against the first isolate, were observed. However, identical restriction patterns and virtually identical hybridization patterns with probes containing the conserved genes of the Mycoplasma capricolum rRNA operon and the Escherichia coli elongation factor Tu suggest that the protein differences might reflect antigenic variation by M. hominis during infection.     

Laparoscopic appendectomy. Our experience

The advantages and applications of the videolaparoscopic technique (VL) versus open surgery in the treatment of acute and complicated appendicitis are not well defined. Our study examined 150 patients, 67 males and 83 females. They underwent surgery for acute appendicitis in emergency. The choice between open or laparoscopic tecnique was due to patient's clinical conditions and surgeon's experience. Two of these patients had no infiammatory process. Eleven patients were affected by gynaecological diseases. The last 137 patients underwent surgery for acute appendicitis and the diagnosis was confirmed. Among them, 35 (25%) were affected by a complicated appendicitis with diffuse or clearly defined peritonitis. In 134 patients the surgery was completed laparoscopically. The conversion rate was 2%. Morbility rate was 3%, due to intra abdominal abscesses secondary to acute complicated appendicitis. The mean operative time was 76 min and the mean hospital stay was 4.8 days. The death rate was 0%. In our experience, laparoscopic appendectomy has significant advantages over traditional open surgery in both acute and complicated appendicitis, especially in young women. In this way, we can diagnose pelvic disease that could be characterized by the same symptoms of acute appendicitis, then we suggest laparoscopic appendectomy even just to complete the diagnostic iter. Laparoscopy is useful in terms of convalescence, postoperative pain, hospital stay, aesthetic outcome and an easier exploration of the peritoneal cavity.     

Advanced MRI imaging of nerve roots in lumbar radiculopathy due to discoradicular conflict: DWI,DTI, and T2 mapping with clinical and neurophysiological correlations

Purpose

To evaluate the lumbar nerve root alterations in patients with lumbar disc herniation sciatica using advanced multimodality MRI sequences and the correlations with clinical and neurophysiological findings.

Material and methods

We prospectively evaluated 45 patients suffering from unilateral lumbar radiculopathy due to disco radicular conflict. All patients underwent MRI examinations using a standard MRI protocol and additional advanced MRI sequences (DWI, DTI, and T2 mapping sequences). Relative metrics of ADC, FA, and T2 relaxation times were recorded by placing ROIs at the pre-, foraminal, and post-foraminal level, either at the affected side or the contralateral side, used as control. All patients were also submitted to electromyography testing, recording the spontaneous activity, voluntary activity, F wave amplitude, latency, and motor evoked potentials (MEP) amplitude and latency, both at the level of the tibialis anterior and the gastrocnemius. Clinical features (diseases duration, pain, sensitivity, strength, osteotendinous reflexes) were also recorded.

Results

Among clinical features, we found a positive correlation of pain intensity with ADC values of the lumbar nerve roots. The presence of spontaneous activity was correlated with lower ADC values of the affected lumbar nerve root. F wave and MEP latency were correlated with decreased FA values at the foraminal level and increased values at the post-foraminal level. The same neurophysiological measures correlated positively with pre-foraminal T2 mapping values and negatively with post-foraminal T2 mapping values. Increased T2 mapping values at the foraminal level were correlated with disease duration.

Conclusions

Evaluation of lumbar nerve roots using advanced MRI sequences may provide useful clinical information in patients with lumbar radiculopathy, potentially indicating active inflammation/myelinic damage (DTI, T2 mapping) and axonal damage/chronicity (DWI).

     

Activity of azelaic acid on cultures of lymphoma- and leukemia-derived cell lines, normal resting and stimulated lymphocytes and 3T3 fibroblasts

Azelaic acid (C9- -dicarboxylic acid) is a competitive inhibitor of tyrosinase and some oxidoreductase in vitro, and in vivo has a beneficial effect on lentigo maligna and malignant melanoma. A definite cytotoxic effect in cultures of malignant melanocytes was also reported. In order to establish if the cytotoxic effect of the diacid is exerted equally in the absence of tyrosinase, lymphoma- and leukemia-derived cell lines were cultured for 72 hr with 10(-3) M, 10(-2) M and 5 X 10(-2) M C9 disodium salt. Normal resting lymphocytes, lymphocytes activated by phytohemoagglutinin, and mouse Balb/c 3T3 fibroblasts were also tested to study a possible effect of azelaic acid on DNA synthesis and cell duplication. At 10(-3) M C9 had no effect on the viability of all the cells tested; at 10(-2) M and 5 X 10(-2) M, C9 2Na had a 50-80% cytotoxic effect on lymphoma- and leukemia-derived cell lines, while at the same concentrations it was not toxic to normal lymphocytes, either resting or stimulated, or to 3T3 fibroblasts. The experiments on cellular incorporation of (1-9 14C) azelaic acid showed that the radiocarbon uptake was two to three times higher for lymphoma- and leukemia-derived cell lines than for lymphocytes, either resting or stimulated, or 3T3 fibroblasts. Biochemical analysis revealed that the diacid underwent beta-oxidation in all the cell cultures. Fractionated centrifugations of 3T3 fibroblasts cultured in the presence of radiolabelled azelaic acid (2 X 10(-4) M) plus cold C9 2Na (10(-2) M), showed that the radioactivity was mainly concentrated in the cytoplasm. The results, being similar to those obtained by adding azelaic acid to cultures of melanoma cells, suggest that the cytotoxic effect of azelaic acid may be due to interference with mitochondrial oxido-reductase enzymes, rather than with tyrosinase. The difference in reaction between lymphoma- and leukemia-derived cell lines and normal or stimulated lymphocytes, and 3T3 fibroblasts, could be explained on the basis of a different degree of permeability of the cell membrane, and/or to a possible different sensitivity of reaction of mitochondrial functions. A similar argument could be used to explain the absence of an effect of dicarboxylic acids upon normal as compared with hyperactive or malignant melanocytes in vivo.     

Associations between social determinants of health,perceived discrimination,and body mass index on symptoms of depression among young African American mothers

PurposeThe association between symptoms of depression and risks for cardiovascular disease (CVD) remains equivocal for African American (AA) mothers. We examined the association between social determinants of health (perceived discrimination), and cardiovascular risk (BMI) on symptoms of depression in a sample of young AA mothers.MethodsSecondary data from 219 adult AA mothers between the ages of 21 and 46 with an average BMI of 29.8 and yearly family income of $14,999 were analyzed using a latent growth model that evaluated four time points to assess changes in symptoms of depression.ResultsInitial BMI was significantly associated with initial symptoms of depression (b = 0.12, p = .019). Perceived discrimination (unfair treatment) was associated with higher initial symptoms of depression (b = 1.14, p = .017).ConclusionThe findings suggest that elevated BMI and perceived discrimination are associated with higher reported symptoms of depression among young, socioeconomically disadvantaged AA mothers. These results advance the scientific understanding of young AA mothers' risk for symptoms of depression and CVD by elucidating the impact of perceived discrimination and social experiences on mental health. Further studies of SDoH and CVD risk factors and perceived racism and depression are needed to shed light on the long-term mental health impact on AA mothers and their children.     

Isoprinosine enhances the activation of sensitized lymphocytes by Epstein-Barr virus antigens

Isoprinosine, a synthetic purine derivative and a potentially useful immunostimulating agent, was tested for its ability to enhance lymphocyte responses to Epstein-Barr virus (EBV) antigens and to autologous EBV-transformed lymphocytes. Isoprinosine significantly enhanced the response of sensitized lymphocytes (i.e. from EBV-seropositive individuals) to EBV antigens, while it has no effect on the lack of response of unsensitized lymphocytes (i.e. from EBV-seronegative individuals) to these antigens. In addition, isoprinosine enhanced lymphocytes response to autologous EBV-transformed cells, and potentiated the generation of cytotoxic lymphocytes. From these observations, and since immunosuppression is commonly observed in EBV-associated malignancies and other EBV-induced disorders, it may be important to point out that the use of isoprinosine as an immunostimulating agent in patients with these diseases deserves serious consideration.     

Helicobacter pylori in dental plaque and stomach of patients from Northern Brazil

AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR co...