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Dopamine receptors in schizophrenia
HIV co-infection with
a
currently
non-pathogenic flagellate
Figure: Comparison of systolic and diastolic flow after LAST procedure in LIMA-LAD graft and ungrafted right internal mammary artery (RIMA) patency of the LIMA to LAD can be immediately assessed at the end of the procedure with a transthoracic pulse-wave diastolic
This flow
procedure will show
a greatly increased the LIMA compared with the predominantly systolic flow in the ungrafted right internal mammary artery, confirming patency (figure). In our experience so far, this minimally invasive approach is safe and should be regarded as the primary intervention in the management of patients with isolated LAD disease, or as a method of achieving partial revascularisation in those patients in whom there are contraindications to conventional cardiac surgical approaches. Furthermore, the protection conferred by a patent LIMA-LAD graft may allow safe angioplasty revascularisation to the proximal LAD or to other diseased coronary arteries.
doppler.
in
Antonio Maria Calafiore, *G D Angelini Department of Cardiac Surgery, San Camillo de’Lellis Hospital, Chieti, Italy; and Bristol Heart Institute, Bristol Royal Infirmary, Bristol BS2 8HW, UK 1
Stanbridge R De L, Symons GV, Banwell PE. Minimal-access surgery for coronary artery revascularisation. Lancet 1995; 346: 837.
Dopamine receptors in schizophrenia SiR-Gjedde and colleagues (Nov 11, p 1302)’ make three critical remarks concerning our Sept 16 review. First, our PET studies of D dopamine receptors in drug naive schizophrenic patients certainly indicate a substantial reduction of Dl dopamine receptor binding, both in the striatum and in the frontal cortex. We apologise for the error 2
SIR-HIV and Leishmayzia infantuna co-infection is common in southern European intravenous drug users.’ When characterising parasite variability among them,= we found an unusual Leishmania-like parasite. A 35-year-old female intravenous drug user living in Madrid was diagnosed HIV-positive in 1986. Her medical history included herpes zoster infections in 1985 and 1987. The patient had fever for 2 months before admission in to 1991 with lymphadenopathy, hospital retinal and haemorrhages. hepatosplenomegaly,
infection, candidosis, Pneumocystis Cytomegalovirus pneumonia, and herpes labialis were diagnosed. Visceral leishmaniasis was suspected because of clinical and laboratory findings: 1450 leucocytes/l, packed cell volume 27-5%, platelets 75 000/[tl’, total protein (71 g/L). CD4 count was 150/13. Immunofluorescence antibody test for leishmaniasis was borderline, with a titre of 1/80. Amastigotes were not seen in bone-marrow aspirate although flagellates were isolated. The patient was treated for 21 days with meglumine antimoniate (20 mg/kg per day) and recovered fully; 3 years after treatment no relapses were detected. Giemsa-stained preparations from cultured promastigotes excluded Trypanosoma infection (figure). When the stock was typed by isoenzyme electrophoresis, it showed a different pattern to that of Leishmania reference strains. Furthermore, kDNA and nDNA from this stock did not hybridise with kDNA (307/K-l)-specific and nDNA (7-059, pDk20, Leishmania pDklO)-specific probes. Promastigote ultrastructure was examined by transmission and scanning electron microscopy but was non-contributory. Promastigotes did not infect Balb/c mice or Syrian golden hamsters. Likewise, it was not possible to establish infection in laboratory-reared Phlebotomus perniciosus but a few promastigotes were found in the gut of Rhodnius prolixus. Insect parasites known as "lower trypanosomatids" were tested. Both kDNA and nDNA cross-hybridisation from the current stock with several lower trypanosomatid genera (Crithidia fasciculata, Herpetomonas muscarum, Leptomonas ctenocephali, Blastocrithidia spp, and Sauroleishmania spp)and other trypanosomatids (Trypanosoma cruzi, Phytomonas tomate, Endotrypanum schaudinna) did not reveal any homology.
and
in table 1: the data show
mean values with SD and not SE. the Second, controversy concerning Ddopamine receptors in schizophrenia was discussed extensively in the paper by Nordstrom et al. Our main objective concerns the variability obtained with the method used by Wong et al. Our own studies will certainly also in the future deal with possible alterations of Ddopamine receptors in schizophrenia. Lastly, we agree with Gjedde and colleagues’ statement that one study indicates a therapeutic potential of glycine in schizophrenic negative symptomatology. However, these clinical results certainly do not prove that this effect is mediated by stimulation of glutamate transmission. Although glycine interacts synergistically with glutamate receptors by modulating a heterotopic glycine receptor, it
does
not seem
correct to
classify glycine
as
a
glutamate
agonist. Göran Sedvall, Lars Farde Department of Clinical Neuroscience, Psychiatry Section, Karolinska Hospital, S-171 76 Stockholm, Sweden
1
Gjedde A,
2
Reith J,
Wong D. Dopamine receptors in schizophrenia.
1995; 346: 1302-03. Sedvaal G, Farde L. Chemical brain anatomy in schizophrenia. Lancet 1996; 346: 743-49
Lancet
264
Figure: Promastigote cultures RPM]-10% FCS. Giemsa staining (X1250). A.-Leishmania infantum reference stock (LEM-75). and B.-Non-Leishmania flagellate showing blunt end and larger and more dense kinetoplast.
a
currently
non-pathogenic flagellate
Figure: Comparison of systolic and diastolic flow after LAST procedure in LIMA-LAD graft and ungrafted right internal mammary artery (RIMA) patency of the LIMA to LAD can be immediately assessed at the end of the procedure with a transthoracic pulse-wave diastolic
This flow
procedure will show
a greatly increased the LIMA compared with the predominantly systolic flow in the ungrafted right internal mammary artery, confirming patency (figure). In our experience so far, this minimally invasive approach is safe and should be regarded as the primary intervention in the management of patients with isolated LAD disease, or as a method of achieving partial revascularisation in those patients in whom there are contraindications to conventional cardiac surgical approaches. Furthermore, the protection conferred by a patent LIMA-LAD graft may allow safe angioplasty revascularisation to the proximal LAD or to other diseased coronary arteries.
doppler.
in
Antonio Maria Calafiore, *G D Angelini Department of Cardiac Surgery, San Camillo de’Lellis Hospital, Chieti, Italy; and Bristol Heart Institute, Bristol Royal Infirmary, Bristol BS2 8HW, UK 1
Stanbridge R De L, Symons GV, Banwell PE. Minimal-access surgery for coronary artery revascularisation. Lancet 1995; 346: 837.
Dopamine receptors in schizophrenia SiR-Gjedde and colleagues (Nov 11, p 1302)’ make three critical remarks concerning our Sept 16 review. First, our PET studies of D dopamine receptors in drug naive schizophrenic patients certainly indicate a substantial reduction of Dl dopamine receptor binding, both in the striatum and in the frontal cortex. We apologise for the error 2
SIR-HIV and Leishmayzia infantuna co-infection is common in southern European intravenous drug users.’ When characterising parasite variability among them,= we found an unusual Leishmania-like parasite. A 35-year-old female intravenous drug user living in Madrid was diagnosed HIV-positive in 1986. Her medical history included herpes zoster infections in 1985 and 1987. The patient had fever for 2 months before admission in to 1991 with lymphadenopathy, hospital retinal and haemorrhages. hepatosplenomegaly,
infection, candidosis, Pneumocystis Cytomegalovirus pneumonia, and herpes labialis were diagnosed. Visceral leishmaniasis was suspected because of clinical and laboratory findings: 1450 leucocytes/l, packed cell volume 27-5%, platelets 75 000/[tl’, total protein (71 g/L). CD4 count was 150/13. Immunofluorescence antibody test for leishmaniasis was borderline, with a titre of 1/80. Amastigotes were not seen in bone-marrow aspirate although flagellates were isolated. The patient was treated for 21 days with meglumine antimoniate (20 mg/kg per day) and recovered fully; 3 years after treatment no relapses were detected. Giemsa-stained preparations from cultured promastigotes excluded Trypanosoma infection (figure). When the stock was typed by isoenzyme electrophoresis, it showed a different pattern to that of Leishmania reference strains. Furthermore, kDNA and nDNA from this stock did not hybridise with kDNA (307/K-l)-specific and nDNA (7-059, pDk20, Leishmania pDklO)-specific probes. Promastigote ultrastructure was examined by transmission and scanning electron microscopy but was non-contributory. Promastigotes did not infect Balb/c mice or Syrian golden hamsters. Likewise, it was not possible to establish infection in laboratory-reared Phlebotomus perniciosus but a few promastigotes were found in the gut of Rhodnius prolixus. Insect parasites known as "lower trypanosomatids" were tested. Both kDNA and nDNA cross-hybridisation from the current stock with several lower trypanosomatid genera (Crithidia fasciculata, Herpetomonas muscarum, Leptomonas ctenocephali, Blastocrithidia spp, and Sauroleishmania spp)and other trypanosomatids (Trypanosoma cruzi, Phytomonas tomate, Endotrypanum schaudinna) did not reveal any homology.
and
in table 1: the data show
mean values with SD and not SE. the Second, controversy concerning Ddopamine receptors in schizophrenia was discussed extensively in the paper by Nordstrom et al. Our main objective concerns the variability obtained with the method used by Wong et al. Our own studies will certainly also in the future deal with possible alterations of Ddopamine receptors in schizophrenia. Lastly, we agree with Gjedde and colleagues’ statement that one study indicates a therapeutic potential of glycine in schizophrenic negative symptomatology. However, these clinical results certainly do not prove that this effect is mediated by stimulation of glutamate transmission. Although glycine interacts synergistically with glutamate receptors by modulating a heterotopic glycine receptor, it
does
not seem
correct to
classify glycine
as
a
glutamate
agonist. Göran Sedvall, Lars Farde Department of Clinical Neuroscience, Psychiatry Section, Karolinska Hospital, S-171 76 Stockholm, Sweden
1
Gjedde A,
2
Reith J,
Wong D. Dopamine receptors in schizophrenia.
1995; 346: 1302-03. Sedvaal G, Farde L. Chemical brain anatomy in schizophrenia. Lancet 1996; 346: 743-49
Lancet
264
Figure: Promastigote cultures RPM]-10% FCS. Giemsa staining (X1250). A.-Leishmania infantum reference stock (LEM-75). and B.-Non-Leishmania flagellate showing blunt end and larger and more dense kinetoplast.