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A Di Rocco

Publications and source records attributed to A Di Rocco.

At least 19 recordsLinked to original sources
PubMed2005

Treatment of Parkinson disease with diet-induced hyperketonemia: a feasibility study.

Ketones may bypass the defect in complex I activity implicated in Parkinson disease (PD). Five of seven volunteers with PD were able to prepare a "hyperketogenic" diet at home and adhere to it for 28 days. Substituting unsaturated for saturated fats appeared to prevent cholesterol increases in four volunteers. Unified Parkinson's Disease Rating Scale scores improved in all five during hyperketonemia, but a placebo effect was not ruled out.

3-Hydroxybutyric Acid↗
PubMed2005

Dyskinesias predict the onset of motor response fluctuations in patients with Parkinson's disease on L-dopa monotherapy.

The aim of the study was to investigate the relationship between dyskinesias and motor fluctuations in patients with Parkinson's disease on l-dopa monotherapy. We identified 116 patients on l-dopa monotherapy treated between 1965 and 1992 and followed until death. Dyskinesias occurred in 102 patients. Of these, 48 only developed dyskinesias while 54 had both dyskinesias and motor fluctuations. Among patients with both complications, 49 developed dyskinesias before fluctuations, and only five had dyskinesias after the onset of fluctuations. Our findings suggest that dyskinesias predict the onset of motor fluctuations, and may share a common pathophysiological mechanism.

Age of Onset↗
PubMed2004

Treatment of AIDS-associated myelopathy with L-methionine: a placebo-controlled study.

BACKGROUND: The histopathology of AIDS-associated myelopathy (AM) closely resembles that of myelopathies due to cobalamin or folate deficiency, with white matter vacuolization in the spinal cord. The pathogenesis of AM appears unrelated to direct HIV infection of the spinal cord. There is abnormal trans-methylation metabolism in AM, with decreased availability of the methyl group donor S-adenosyl-methionine (SAM). The authors hypothesized that treatment with l-methionine, the direct metabolic precursor of SAM, might improve AM. OBJECTIVE: To determine the safety and efficacy of l-methionine treatment in AM. METHODS: Fifty-six patients with clinical diagnosis of AM were randomized to a Phase II, double-blind, placebo-controlled study comparing the effect of l-methionine 6 g/day in two divided doses with that of placebo. Study duration was 12 weeks. All patients had somatosensory evoked potentials with prolonged central conduction time (CCT) at entry. Change in CCT was the primary endpoint of the study. Frequency of adverse events (AEs) was used to assess safety. Secondary endpoints were strength, spasticity, and urinary function. Biochemical measurements included serum methionine and homocysteine and CSF SAM. RESULTS: There were no significant differences in AEs between the two groups. Serum homocysteine increased in l-methionine-treated patients from 7.2 (+/-5.2 SD) to 12.6 (+/-6.15 SD) micromol/L. The mean CCT at baseline was 25.9 milliseconds (+/-7.3 SD) for the treatment group and 24.1 milliseconds (+/-7.0 SD) for the placebo group. At completion, it was 3.0 milliseconds (+/-6.1 SD) for the treatment group and 23.6 milliseconds (+/-5.5 SD) for the placebo group (p = 0.17). In a subset of 15 patients with CSF studies, SAM levels increased in the l-methionine but not in the placebo group (p = 0.07). There was no significant effect of treatment on strength, spasticity, or urinary function. CONCLUSIONS: l-methionine was safe and well tolerated although in some patients induced an increase of serum homocysteine. There was a nonsignificant improvement in CCT in treated patients but no benefit in any of the clinical measures.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Abnormal cobalamin-dependent transmethylation in AIDS-associated myelopathy.

BACKGROUND: White matter vacuolization of the spinal cord is common in patients with AIDS and may lead to clinical manifestations of myelopathy. The pathogenesis of AIDS-associated myelopathy (AM) is unknown and may be related to metabolic abnormalities rather than to direct HIV infection. The striking pathologic similarity between AM and the vacuolar myelopathy associated with vitamin B(12) deficiency suggests that abnormal metabolism of the B(12)-dependent transmethylation pathway may be important in the pathogenesis of AM. METHODS: The authors compared S-adenosyl-methionine (SAM), methionine, homocysteine, and glutathione in serum and CSF of 15 patients with AM vs. 13 HIV-infected controls without myelopathy (HWM). They also compared the results with a non-HIV--infected reference population (NC). All patients had normal B(12), folate, and methylmalonic acid levels. RESULTS: There was a decrease in CSF SAM in the AM group compared with the HWM group (p < 0.0001) and the NC group (p < 0.0001). CSF SAM in the HWM group was also lower than that in the NC group (p = 0.015). Serum methionine was also reduced in serum of the myelopathic group compared with the NC group (p = 0.006). CONCLUSIONS: AM is associated with an abnormality of the vitamin B(12)-dependent transmethylation pathway.

Adult↗
PubMed2001

COMT-dependent protection of dopaminergic neurons by methionine, dimethionine and S-adenosylmethionine (SAM) against L-dopa toxicity in vitro.

L-dopa may be toxic to dopamine neurons, possibly due to catechol-autoxidation. Catechols are O-methylated by catechol-O-methyltransferase (COMT) in a SAM consuming reaction, preventing the initiation of catechol autoxidation. We hypothesized that SAM or SAM-precursors ameliorate L-dopa neurotoxicity, in a COMT-dependent fashion. We tested this hypothesis in primary mesencephalic cultures by adding 200 microM L-dopa with 2 mM methionine or 1 mM dimethionine or 0.5 mM SAM with or without 0.2 microM of the COMT-inhibitor 2', 5'-dinitrocatechol (OR 486). L-dopa was found to be neurotoxic as the surviving neurons had fewer and shorter processes. Methionine, dimethionine and SAM all protected DA neurons against damaged induced by L-dopa. The COMT inhibitor dinitrocatechol (DNC) completely abolished the protective effect against L-dopa toxicity. We conclude that supplementation with methionine, dimethionine or SAM ameliorates L-dopa neurotoxicity to dopamine neurons, while inhibition of COMT may aggravate or unmask L-dopa neurotoxicity.

Animals↗
PubMed2000

AIDS myelopathy is not associated with elevated HIV viral load in cerebrospinal fluid.

The pathogenesis of AIDS-associated myelopathy is unknown. Elevated HIV-1 viral load in CSF has been associated with cognitive impairment. The authors investigated if a similar association exists in patients with myelopathy. The authors evaluated levels of HIV-1 RNA in the CSF of 16 individuals with AIDS myelopathy and in 16 nonmyelopathic HIV-infected control subjects. There was no correlation between levels of HIV-1 RNA and the presence or severity of myelopathy.

Acquired Immunodeficiency Syndrome↗
PubMed2000

The role of somatosensory evoked potentials in the diagnosis of AIDS-associated myelopathy.

BACKGROUND: Although AIDS-associated vacuolar myelopathy is detected in >50% of autopsy cases, it is often unrecognized during life. The clinical assessment is often difficult because of concurrent peripheral neuropathy and lack of specific diagnostic markers. Somatosensory evoked potentials (SEPs) have been successfully used to evaluate central conduction in a number of diseases involving the spinal cord. OBJECTIVES: To assess the diagnostic yield of SEPs in AIDS-associated myelopathy. METHODS: We recorded tibial and median nerve SEPs in 69 HIV-infected subjects referred for evaluation of lower extremity neurologic abnormalities. Stimulation of the peroneal nerve at the popliteal fossa was performed in patients with absent response to ankle stimulation. RESULTS: HIV-infected subjects had significantly delayed latencies of both peripheral and central potentials, suggesting a combination of peripheral and CNS abnormalities. Analysis of peripheral and central latencies allowed us to discriminate between neuropathy and myelopathy in individual patients. Abnormalities of tibial central conduction time (CCT) correlated with clinical diagnosis of myelopathy. There was no significant difference in median CCTs between patients and controls, suggesting that conduction abnormalities were restricted to the thoracolumbar spinal cord. A derived spinal conduction time was a sensitive indicator of central conduction abnormalities in AIDS patients with myelopathy. CONCLUSIONS: The combination of median, posterior tibial, and peroneal SEPs is a valuable tool in the diagnosis of AIDS-associated myelopathy, particularly when myelopathy and peripheral neuropathy coexist. The use of a derived spinal conduction time improves the diagnostic yield of SEPs in AIDS-associated myelopathy.

Acquired Immunodeficiency Syndrome↗
PubMed2000

S-Adenosyl-Methionine improves depression in patients with Parkinson's disease in an open-label clinical trial.

We report a pilot study of S-adenosyl-methionine (SAM) in 13 depressed patients with Parkinson's disease. All patients had been previously treated with other antidepressant agents and had no significant benefit or had intolerable side effects. SAM was administered in doses of 800 to 3600 mg per day for a period of 10 weeks. Eleven patients completed the study, and 10 had at least a 50% improvement on the 17-point Hamilton Depression Scale (HDS). One patient did not improve. Two patients prematurely terminated participation in the study because of increased anxiety. One patient experienced mild nausea, and another two patients developed mild diarrhea, which resolved spontaneously. The mean HDS score before treatment was 27.09 +/- 6.04 (mean +/- standard deviation) and was 9.55 +/- 7.29 after SAM treatment (p < 0.0001). Although uncontrolled and preliminary, this study suggests that SAM is well tolerated and may be a safe and effective alternative to the antidepressant agents currently used in patients with Parkinson's disease.

Aged↗
PubMed1999

Diseases of the spinal cord in human immunodeficiency virus infection.

The most common disease of the spinal cord in human immunodeficiency virus (HIV) infection is vacuolar myelopathy. Pathology studies have demonstrated that vacuolization in the thoracic spinal cord is present in more than a third of patients with AIDS. The disease, however, manifests clinically only when the vacuolization in the spinal cord has become severe, with prominent myelin loss in the lateral and posterior columns. Vacuolar myelopathy presents usually with slowly progressing spastic paraparesis, accompanied by loss of vibratory and position sense and urinary frequency and urgency. In males, erectile dysfunction can be an early manifestation of the disease. The pathogenesis of vacuolar myelopathy is unknown but may be related to abnormal trans-methylation mechanisms induced by the HIV virus and cytokines. There is no known treatment for the disease, although therapy with methylating agents is being investigated. There are other rarer causes of spinal cord disease in AIDS, including a number of infectious myelitis and neoplastic and vascular myelopathies.

HIV Infections↗
PubMed1999

MR findings in AIDS-associated myelopathy.

BACKGROUND AND PURPOSE: The most common cause of spinal cord disease among patients with AIDS or those infected with HIV-1 is AIDS-associated myelopathy. The purpose of this study was to determine the MR characteristics of the spinal cord in this patient population and to correlate these findings with the clinical severity of myelopathy. METHODS: MR images of the spinal cord in 21 patients with documented HIV-1 infection or AIDS and a clinical diagnosis of AIDS-associated myelopathy were assessed retrospectively for atrophy, intrinsic signal abnormality, and abnormal enhancement. The clinical severity of myelopathy was graded by a neurologist on the basis of physical examination, and a qualitative correlation was made with the MR findings. RESULTS: MR findings were abnormal in 18 of the 21 patients. The most common feature was spinal cord atrophy (n = 15), typically involving the thoracic cord with or without cervical cord involvement, followed by intrinsic cord signal abnormality (n = 6), and normal-appearing cord (n = 3). Three patients had both cord atrophy and intrinsic cord signal abnormality. The cord signal abnormality was diffuse, without predilection for any specific distribution pattern. Enhancement was not seen in any of the 10 patients who received intravenous contrast material. Only one of 16 patients with moderate to severe myelopathy had normal MR findings, as compared with two of five patients with mild myelopathy. CONCLUSION: MR findings in the spinal cord are abnormal in the majority of patients with AIDS-associated myelopathy, typically showing spinal cord atrophy, with or without intrinsic cord signal abnormality. Patients with moderate to severe myelopathy have an increased frequency of spinal cord abnormalities, but a definite correlation between clinical severity of myelopathy and extent of MR abnormalities remains to be established.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Sertraline induced parkinsonism. A case report and an in-vivo study of the effect of sertraline on dopamine metabolism.

We report a patient with a parkinsonian syndrome induced by sertraline (Zoloft), an SSRI antidepressant, whose symptoms resolved after the drug was discontinued. This case prompted us to investigate the effect of sertraline on dopamine metabolism in animals. Sertraline (30 mg/kg, i.p.) or placebo (vehicle) was administered to two groups of six normal, anesthetized rats and using cerebral microdyalisis extracellular striatal levels of dopamine, the dopamine metabolites (HVA and DOPAC), as well as the serotonin metabolite 5-HIIA were monitored. In animals pre-treated with sertraline, DOPAC, HVA, and 5-HIAA levels were significantly decreased compared to control animals (p < 0.01). These data indicate that sertraline has an effect on dopamine metabolism, which may alter function in the striatum and induce a parkinsonian syndrome.

1-Naphthylamine↗
PubMed1998

AIDS-associated vacuolar myelopathy.

AIDS-associated vacuolar myelopathy (VM) is a common neurologic complication of AIDS. Pathologically, VM is characterized by vacuolization in the lateral and posterior columns of the thoracic spinal cord and has a striking similarity with the myelopathy of vitamin B12 deficiency. In autopsy series, 20% to 55% of patients with AIDS have evidence of spinal cord disease consistent with VM. The myelopathy usually manifests late in the course of HIV infection, with slowly progressive weakness of the lower extremities, gait disorder, sensory abnormalities in the legs, impotence in men, and urinary frequency and urgency. Its course is invariably progressive and leads to severe paralysis of the lower limbs, with loss of the ability to walk and of sphincter control. The differential diagnosis is extensive and includes metabolic, infective, and neoplastic spinal cord diseases. The diagnosis is based on the clinical observation and the exclusion of other causes of myelopathy via serologic, radiographic, and cerebrospinal fluid studies. The pathogenesis of VM is unknown. Attempts to detect HIV in the spinal cord have not yielded significant results, and there is no evidence of a relationship between the presence of HIV and the development of myelopathy. A metabolic disorder of the vitamin B12-dependent transmethylation pathway, induced by HIV or cytokine activation, is considered the possible cause of VM associated with AIDS. There is no known treatment for AIDS myelopathy and there is no evidence that antiretroviral drugs can improve the symptoms or slow the progression of VM. The symptomatic treatment includes antispasticity agents, management of sphincter dysfunction, and physical therapy. Experimental treatments are being tested in clinical trials.

Diagnosis, Differential↗
PubMed1998

A pilot study of L-methionine for the treatment of AIDS-associated myelopathy.

The pathogenesis of AIDS-associated vacuolar myelopathy (VM) may be related to abnormality of transmethylation mechanisms in the nervous system. To evaluate the safety and potential efficacy of the methyl-group donor L-methionine in AIDS-associated VM, we conducted a pilot clinical trial in 12 patients with VM. Seven of the nine patients who completed the study had clinical and electrophysiologic improvement. Controlled studies may be indicated to assess the efficacy and safety of L-methionine in AIDS-associated VM.

Acquired Immunodeficiency Syndrome↗