Early hyperdopaminergic state following sub-thalamic nucleus deep brain stimulation in Parkinson disease

BACKGROUND

Hyperdopaminergic state (HS), especially impulse control behaviors (ICBs), are not rare in Parkinson's disease (PD). Controversial data regarding HS prevalence one year following sub-thalamic nucleus deep brain stimulation (STN-DBS) are reported.

OBJECTIVE

Our objectives were to describe early postoperative HS (PoOHS) including ICBs, hypomania and psychotic symptoms during the first 3 months following STN-DBS (V1) and their prognosis at 1 year (V2).

METHODS

This descriptive study included 24 PD patients treated successively with bilateral STN-DBS between 2017 and 2019. The primary endpoint was prevalence of PoOHS at V1 according to the Ardouin Scale of Behaviour in Parkinson's Disease.

RESULTS

Prior to STN-DBS (V0), 25% patients had HS (only ICBs) whereas at V1 (during the 3 first months), 10 patients (41.7%) had one or several HS (P=0.22) (de novo in 29.2%): 7 (29.2%) ICBs, 4 (16.7%) hypomanic mood, 1 (4.7%) psychotic symptoms. At V2, all V0 and V1 HS had disappeared, while 1 patient (4.2%) presented de novo HS (P<0.01). No correlation was found between the occurrence of PoOHS at V1 and any V0 data. Higher levodopa equivalent dose of dopamine agonists at V1 was correlated with ICB at V1 (P=0.04).

CONCLUSION

We found that early PoOHS are frequent in PD after STN-DBS, mostly de novo, with ICBs and hypomania being the most frequent. Despite a good prognosis of PoOHS at one year, our work emphasizes the importance of both a cautious adjustment of dopamine agonist doses and a close non-motor monitoring pre- and post-STN-DBS in PD.

An ergonomic evaluation of surgeons' axial skeletal and upper extremity movements during laparoscopic and open surgery

BACKGROUND

Many surgeons have complained of fatigue and musculoskeletal pain after laparoscopic surgery. We evaluated differences in surgeons' axial skeletal and upper extremity movements during laparoscopic and open operations.

METHODS

Five surgeons were videotaped performing 16 operations (8 laparoscopic and 8 open) to record their neck, trunk, shoulder, elbow, and wrist movements during the first hour of surgery. We also compared postprocedural complaints of pain, stiffness, or numbness between the two groups.

RESULTS

Compared with surgeons performing open surgery, surgeons performing laparoscopic surgery exhibited less lateral neck flexion; less trunk flexion; more internal rotation of the shoulders; more elbow flexion; more wrist supination and wrist ulnar and radial deviation. There was a trend of more shoulder stiffness after laparoscopic operations than after open operations.

CONCLUSIONS

Laparoscopic surgery involves a more static posture of the neck and trunk, but more frequent awkward movements of the upper extremities than open surgery. Ergonomic changes in the operating room environment and instrument design could ease the physical stress imposed on surgeons during laparoscopic operations.

Muscarinic receptor-mediated inhibition of GDP-activated adenylyl cyclase suggests a direct interaction of inhibitory guanine nucleotide-binding proteins and adenylyl cyclase

To differentiate the effects of GDP and GTP on adenylyl cyclase regulation, adenylyl cyclase in canine sarcolemmal membranes was studied under conditions where only 3-12% of added GDP was converted to GTP by membrane-associated nucleoside diphosphate kinase. Adenylyl cyclase was stimulated up to 180% by GDP at 7-fold lower concentrations than required for stimulation by GTP (GDP half-maximal activation, 120 nM; GTP half-maximal activation, 830 nM). Transphosphorylation of GDP to GTP was blocked completely by the addition of 3 mM UDP. However, UDP did not affect GDP-mediated adenylyl cyclase activation, and guanosine 5'-O-(2-thiodiphosphate) had the same effect on adenylyl cyclase activity as did GDP, indicating that GDP-mediated stimulation of adenylyl cyclase was not due to transphosphorylation of GDP to GTP. Carbachol inhibited GDP-stimulated adenylyl cyclase activity even without addition of GTP; however, this inhibition was clearly dependent upon the endogenous formation of GTP. Half-maximal adenylyl cyclase inhibition by carbachol required the addition of either 330 nM GDP or 25 nM GTP. Taking into account a 3-12% conversion of GDP to GTP by membrane-associated nucleoside diphosphate kinase, sufficient GTP was generated from GDP to support receptor-mediated inhibition of adenylyl cyclase. In addition carbachol-mediated adenylyl cyclase inhibition in the presence of GDP, but not GTP, was blocked completely by 3 mM UDP. In conclusion, GDP-activated adenylyl cyclase could be inhibited by carbachol in the presence of GTP concentrations that were 34-fold below the concentrations needed for GTP-mediated activation of stimulatory guanine nucleotide-binding proteins. In addition, at low GTP concentrations carbachol reduced adenylyl cyclase to levels below "basal" activity (activity in the absence of guanine nucleotides). Although indirectly, these results suggest that carbachol-mediated inhibition of adenylyl cyclase may be independent of Gs activity and possibly due to direct interaction of inhibitory guanine nucleotide-binding proteins and adenylyl cyclase.

cDNA-cloning, sequencing and expression in glucocorticoid-stimulated quiescent Swiss 3T3 fibroblasts of mouse lipocortin I

We isolated and sequenced mouse lipocortin I cDNA clones from a lambda gt10 cDNA library prepared from Swiss 3T3 mRNA. The homology with human lipocortin I at the amino acid level is 86%. When confluent layers of Swiss 3T3 cells were stimulated with 10% fetal calf serum, expression of lipocortin I was strongly stimulated. In parallel, DNA synthesis was induced with a peak at 24 hours after glucocorticoid treatment indicating induction of cell proliferation. In the absence of serum glucocorticoid treatment provoked neither induction of DNA synthesis nor expression of lipocortin I. We conclude that serum contains an unidentified factor, which acts synergistically with glucocorticoids on cell proliferation and lipocortin I expression.

A novel MHC class I molecule as a tumour-specific antigen. Correlation between the antibody-defined and the CTL-defined target structure

Ultraviolet light (UV)-induced tumours in mice are often highly immunogenic and have unique (individually specific) antigens which cause tumour rejection in normal mice. The molecular nature of these unique 'rejection' or 'transplantation' antigens is not known. We have recently isolated a syngeneic monoclonal antibody (mAb), CP28, that recognizes a unique tumour-specific antigen on the UV-induced regressor tumour 1591-RE. Further analysis revealed that the antibody-recognized antigen represents a novel major histocompatibility complex (MHC) class I molecule. However, the relationship of this molecule to the unique T cell-recognized antigen that causes tumour rejection remained unresolved. In this study we have explored the relationship of the antibody-defined tumour-specific novel class I molecule to the rejection antigen, that we have previously defined with a cytolytic T cell (CTL) clone ('anti-A'). Two different lines of evidence suggested a close relationship. First, it was found that random subclones of the 1591-RE tumour expressed different levels of the CP28-defined antigen which correlated with the level of lysis by the anti-A CTL clone. Second, the selection of antigen-loss variants using either the anti-A CTL clone or the mAb CP28 resulted in the simultaneous loss of both the CP28 as well as the 'A' antigen. This tight correlation strongly suggests a relationship between the antibody-defined and the T cell-defined antigen. However, the role of the antibody-recognized antigen in causing transplantation rejection still needs to be determined.

Identification of a unique tumor-specific antigen as a novel class I major histocompatibility molecule

Cancers induced by physical or chemical carcinogens express tumor-specific antigens that are uniquely specific for any given tumor; therefore, there is a seemingly endless variety of these unique antigens. We have studied a UV-induced fibrosarcoma, designated 1591, to elucidate the obscure molecular nature and genetic origins of unique tumor-specific antigens. A monoclonal antibody raised against syngeneic 1591 tumor cells has unique tumor specificity. This tumor-specific monoclonal antibody precipitated from the tumor a 45-kDa molecule associated with a 12-kDa molecule having the pI of beta2-microglobulin. This and other evidence indicated that the 1591 tumor expresses a novel class I molecule. A 1591 variant selected for the absence of binding to the monoclonal antibody lacked the novel class I MHC molecule as well as reactivity with cytotoxic T lymphocytes specific for the 1591 tumor. Furthermore, tumor cells bearing the antigen are rejected while variants that have lost the antigen grow progressively. Fourteen of 14 host-selected progressor tumor variants lost reactivity with the monoclonal antibody and provided further evidence that this novel class I molecule is a transplantation antigen on the parental 1591 tumor required for immune rejection. The identification of a unique tumor-specific antigen as a novel class I major histocompatibility complex gene product allows us to search for the possible genetic mechanisms involved and to explore further the role such molecules play in tumor immunity and malignancy.

Multiple tumour-specific antigens expressed on a single tumour cell

Tumours induced by physical or chemical carcinogens often express tumour-specific antigens that can induce strong protective immune defence in the host. The diversity of these unique antigens among different tumours is seemingly endless, and has been compared to that of immune receptors. At present, the nature and complexity of this antigenicity is not known for any single tumour. Here we describe the unique antigenicity expressed by a murine ultraviolet light (UV)-induced fibrosarcoma. This tumour is clearly subject to immune surveillance by the normal host, and does not grow progressively unless it undergoes antigenic changes. Using defined monoclonal T-cell probes and tumour variants selected in vitro with these probes, we found that the total antigenicity consisted of multiple independent components, all of which were tumour-specific and expressed simultaneously on the same tumour cell. The demonstration of this antigenic complexity will enable us to identify and compare the molecular composition of the components of this antigen, as well as to determine their individual roles in tumour rejection and escape.

Independent immunodominant and immunorecessive tumor-specific antigens on a malignant tumor: antigenic dissection with cytolytic T cell clones

We have analyzed the complexity of a unique tumor-specific transplantation antigen expressed by the murine ultraviolet light-induced fibrosarcoma 1591-RE. This tumor is highly immunogenic and is regularly rejected by normal mice. We have derived a cloned cytolytic T cell line showing a reactivity pattern representative of the cytolytic response of the host rejecting this regressor tumor. Using this T cell line (anti-A), variants of 1591-RE (1591-A-) were selected in vitro that had lost the same antigen as progressor variants of 1591-RE selected by the host in vivo. The in vitro derived variant was then used to generate a second T cell clone (anti-B) that recognized an antigen on the parental tumor that had been retained by the variants derived in vitro. Host-selected progressor variants were also found to have retained this antigen. By selecting for variants in vitro from the parental tumor with the anti-B T cell line, it was shown that the two different antigens (A and B) present on the parental tumor were lost independently of each other. Despite the independence of these two antigens, the host T cell response to the parental regressor tumor was invariably restricted to only the "immunodominant" A antigen.

Independent immunodominant and immunorecessive tumor-specific antigens on a malignant tumor: antigenic dissection with cytolytic T cell clones

We have analyzed the complexity of a unique tumor-specific transplantation antigen expressed by the murine ultraviolet light-induced fibrosarcoma 1591-RE. This tumor is highly immunogenic and is regularly rejected by normal mice. We have derived a cloned cytolytic T cell line showing a reactivity pattern representative of the cytolytic response of the host rejecting this regressor tumor. Using this T cell line (anti-A), variants of 1591-RE (1591-A-) were selected in vitro that had lost the same antigen as progressor variants of 1591-RE selected by the host in vivo. The in vitro derived variant was then used to generate a second T cell clone (anti-B) that recognized an antigen on the parental tumor that had been retained by the variants derived in vitro. Host-selected progressor variants were also found to have retained this antigen. By selecting for variants in vitro from the parental tumor with the anti-B T cell line, it was shown that the two different antigens (A and B) present on the parental tumor were lost independently of each other. Despite the independence of these two antigens, the host T cell response to the parental regressor tumor was invariably restricted to only the "immunodominant" A antigen.

Regulation of myeloma growth in vitro by idiotype-specific T lymphocytes

Spleen cells of BALB/c mice immunized with purified BALB/c myeloma protein (MP) caused idiotype-specific suppression of DNA synthesis and colony formation by myeloma cells in vitro. Lymphocytes from mice immunized with 315-MP inhibited only MOPC-315 plasmacytoma cells; conversely, lymphocytes from mice immunized with 167-MP inhibited only MOPC-167 plasmacytoma cells. Antisera from those mice that showed cell-mediated inhibition of myeloma growth had no significant effect. The suppressive activity of the spleen cells was markedly reduced by treatment with anti-Thy 1.2 and complement, and the immune cells responsible for the suppression did not adhere to nylon wool. The suppressor cells adsorbed to myeloma protein-coated plates, and after elution, inhibited myeloma cells specifically at a 1:1 effector to target cell ratio. Suppression of myeloma growth was due to cytostatic rather than cytolytic effects. These findings suggest that mice immunized with purified myeloma protein have idiotype-specific T cells that can regulate myeloma cell growth. This mechanism may provide an explanation for the transplantation resistance to myelomas induced by immunization with myeloma protein. Similar idiotype-specific T cells may also play a role in the idiotype-specific regulation of immune responses by acting late in differentiation to block the proliferation of antibody-secreting normal B cells.

Regulation of myeloma growth in vitro by idiotype-specific T lymphocytes

Spleen cells of BALB/c mice immunized with purified BALB/c myeloma protein (MP) caused idiotype-specific suppression of DNA synthesis and colony formation by myeloma cells in vitro. Lymphocytes from mice immunized with 315-MP inhibited only MOPC-315 plasmacytoma cells; conversely, lymphocytes from mice immunized with 167-MP inhibited only MOPC-167 plasmacytoma cells. Antisera from those mice that showed cell-mediated inhibition of myeloma growth had no significant effect. The suppressive activity of the spleen cells was markedly reduced by treatment with anti-Thy 1.2 and complement, and the immune cells responsible for the suppression did not adhere to nylon wool. The suppressor cells adsorbed to myeloma protein-coated plates, and after elution, inhibited myeloma cells specifically at a 1:1 effector to target cell ratio. Suppression of myeloma growth was due to cytostatic rather than cytolytic effects. These findings suggest that mice immunized with purified myeloma protein have idiotype-specific T cells that can regulate myeloma cell growth. This mechanism may provide an explanation for the transplantation resistance to myelomas induced by immunization with myeloma protein. Similar idiotype-specific T cells may also play a role in the idiotype-specific regulation of immune responses by acting late in differentiation to block the proliferation of antibody-secreting normal B cells.

Mutagenic and epigenetic influence of caffeine on the frequencies of UV-induced ouabain-resistant Chinese hamster cells

Caffeine, given as a post-treatment to UV-irradiated Chinese hamster cells in vitro, modified the frequency were increased when caffeine was added only for the DNA repair and mutation fixation period. When caffeine was added after the DNA repair and mutation fixation period, or immediately after DNA damage and for the entire repair and selection period, mutation frequencies were reduced. A hypothesis, given to explain both results, is that caffeine, by blocking a constitutive "error-free" postreplication repair process, allows an "error-prone" DNA repair process to produce many mutations. Moreover, caffeine, possibly by modifying C-AMP metabolism, causes a repression of induced mutations which, in effect, explains its anti-mutagenic and anti-carcinogenic properties.

The impact of quality of diet and other factors on birth weight of infants

Quality of the mother's diet, expressed as a NAR index, was significantly correlated (r = 0.301, P less than 0.05) with birth weight of the infant. Eight women who reported that they had smoked during pregnancy had infants with significantly lower birth weights (P less than 0.01), gained less weight during prenatal care (P less than 0.01), and had a lower NAR index (P less than 0.10) than 32 women who said they did not smoke during pregnancy. The relationship of birth weight to 44 maternal and environmental factors was examined by multiple regression analysis to isolate variables significantly and independently related to birth weight. This analysis showed that birth weight of the infant was positively related to number of weeks of gestation, overall dietary quality, delivery weight of the mother squared, age of the mother squared, and number of previous pregnancies squared, and negatively related to weeks of gestation squared, iron and protein intake, age of mother, number of people in the household, and number of cigarettes smoked by the mother per day. Nine factors accounted for up to 86% of the variability in birth weight. Inclusion of quality of the diet improved the prediction equations by 6 to 8%.