Gamma knife radiosurgical management of petroclival meningiomas results and indications

BACKGROUND

Surgical treatment of petroclival meningiomas remains challenging. In order to refine indications for the use of stereotactic radiosurgery in the treatment of these tumours, we retrospectively evaluated our experience in this field.

METHODS

Thirty-two patients harboring a petroclival meningioma were treated consecutively using a Gamma knife between December 92 and June 1998. Eight patients underwent radiosurgery after one or more attempted surgical removals and 24 had radiosurgery as the primary treatment. The main symptoms before radiosurgery were cranial nerve palsies, including a sixth nerve deficit in 10 patients and a trigeminal nerve disturbance in 9. All patients underwent a conformal multi-isocentric treatment (mean isocenter's number 8.8) and the dose delivered at the tumour margin ranged from 10 to 15 Gy (mean dose 13 Gy).

FINDINGS

The duration of follow-up varied from 24 to 118 months (mean clinical follow-up 56 months, mean radiological follow-up 52.6 months). All 32 patients survived. The tumour volume remained unchanged in 28 patients and decreased slightly in 4. Neurological status worsened permanently in 2 patients with a delayed hemiparesis due to focal pontine infarction. These complications were associated with large meningiomas with vascular involvement and ventral brainstem compression, and occurred at the very early stage of our experience. At last follow-up, preoperative fifth or sixth cranial nerve deficits had improved or recovered in 13 out of 19 patients and any delayed worsening or new cranial nerve deficits were not observed after radiosurgery.

CONCLUSIONS

Stereotactic radiosurgery with a Gamma knife provides effective management of small to middle sized petroclival meningiomas and is an alternative to microsurgery. Careful selection of patients and use of major technical refinements should improve the safety of this treatment.

[A retrospective study of 32 lumbar synovial cysts. Clinical aspect and surgical management]

We report a retrospective analysis of a series of 32 cases of lumbar synovial cysts. Clinically, two populations were identified: patients who presented radicular pain mimicking the clinical diagnosis of disk herniation (group I) and patients who presented neurogenic claudication consistent with a diagnosis of lumbar spinal stenosis (group II). The radiological work-up consisted in standard X-rays and CT-scan for all patients. MRI (magnetic resonance imaging) was performed in 14 patients. All the patients were operated on. The surgical technique consisted in foraminotomy for patients in group I and more or less extensive laminectomy for patients in group II. Functional outcome was marked by a significant improvement in 96.9% of the patients and those who presented a motor deficit recovered in 83% of the cases. Based on the findings in this series, we discuss the clinical aspects and the therapeutic management of this pathological entity.

Sweetpotato Virus Disease (SPVD): Distribution, Incidence, and Effect on Sweetpotato Yield in Peru

Sweetpotato virus disease (SPVD), the most important disease affecting sweetpotato (Ipomoea batatas (L.) Lam), is caused by the synergistic interaction of the aphid-transmitted Sweetpotato feathery mottle virus (SPFMV) and whitefly-transmitted Sweetpotato chlorotic stunt virus (SPCSV). In this study, SPVD was the main disease in the Cañete Valley, the major sweetpotato-producing area in Peru. Studies on virus incidence showed that SPCSV and SPFMV were the most frequently identified viruses in Cañete Valley. Symptoms of different severity were associated with isolates of both viruses involved in the SPVD. Over 80% of plants infected with both SPFMV and SPCSV showed the symptoms (leaf reduction and deformation, vein clearing or mosaic, and stunting) typically attributed to SPVD elsewhere. SPFMV did not significantly affect the yield of the sweetpotato cultivars Jonathan and Costanero, but infection of these cultivars by SPCSV was associated with significant yield reduction. Double infection by the two viruses resulted in SPVD and greater yield reduction than for either alone. These results demonstrate that SPFMV and SPCSV interact synergistically and that the severity of SPVD symptoms also depends on the particular isolate of each virus.

[Traumatic spondylolisthesis of the axis: arguments in favor of surgical management after analysis of 8 patients]

BACKGROUND AND PURPOSE

The purpose of this report is to assess the efficacy of primary surgical stabilization in the management of traumatic C2 spondylolisthesis.

MATERIAL AND METHODS

Eight patients including 5 men and 3 women (mean age, 44 years) were treated surgically for traumatic spondylolisthesis of the axis. Three patients presented permanent neurological deficit. The indication for operative treatment included fracture instability and association with either neurological deficit or multiple trauma. External immobilization was attempted and failed in two patients. In all cases the procedure was performed by the anterior route and consisted of surgical fixation with C2/C3 discectomy, intersomatic graft placement, and bone fusion.

RESULTS

Using the Effendi and Levine classification, fractures were classified as type I in 2 cases, type II in 3, type IIa in 2, and type III in 1. The two patients with severe tetraparesis presented spinal cord contusion at the C2/C3 disk level. Postoperative radiography demonstrated C2/C3 fusion in all patients. No surgical complications were observed. The average hospital stay was 4.5 days.

CONCLUSION

Surgical stabilization by C2-C3 fusion via the anterior route is effective for management of all types of traumatic C2 spondylolisthesis. It achieves immediate stability. We recommend its use as a primary intervention not only for unstable lesions but also for lesions associated with neurological deficits or multiple trauma. A major benefit is to facilitate nursing care and patient rehabilitation.

First Report of Sweet potato leaf curl virus in Peru

Leaf curling symptoms have been reported in sweet potato (Ipomoea batatas) plants infected with a geminivirus (1). Leaf curl disease appeared in Peru after the 1997 to 1998 El Niño, when the population and activity of whiteflies (Bemisia tabaci, B. argentifolii, and B. afer) increased. Approximately 6% of plants in farmers' commercial fields in San Ramón, Junín (September 2000) and Cañete, Lima (February 2001) showed typical leaf curling symptoms. Seventeen plants in total were collected from both places, and stem scions from those plants were graft-inoculated to I. setosa, which developed symptoms of leaf curling, interveinal chlorosis, and stunting. Total nucleic acid was obtained from infected sweet potato and I. setosa plants using cetyltrimethylammoniumbromide (CTAB) extraction, and primers PW285-3 (5'-CGT CGT TAG CAG TCT GCA GGC CTC CTC TAG-3') and PW285-4 (5' -AAC TGT AAA TAC GGA ACT GCA GTT CGA ATT-3') for Sweet potato leaf curl virus (SPLCV), developed and provided by R. Valverde and C. Clark of Louisiana State University (2), were used to amplify SPLCV by polymerase chain reaction (PCR). Expected DNA fragments of ca. 900 bp (in all samples) and 2.4 kp (in some samples), characteristic of the subgenomic and genomic DNAs of SPLCV respectively, were obtained from symptomatic but not from symptomless (uninfected) plants. This 2.4-kb fragment was amplified in relatively small amounts compared to the 900-bp fragment. Presence of SPLCV was also confirmed by nucleic acid spot hybridization using a full-length clone of SPLCV-US. Fourteen of 17 plants infected with SPLCV were also infected with Sweet potato chlorotic stunt virus (determined by nitrocellulose membrane enzyme-linked immunosorbent assay serological test), which is also transmitted by whiteflies. These viruses now seem to be common in farmers' fields in San Ramón and Cañete. To our knowledge, this is the first report of SPLCV in Peru. References: (1) P. Lotrakul et al. Plant Dis. 82:1253, 1998. (2) P. Lotrakul and R. A. Valverde. Cloning of a DNA-A like genomic component of sweet potato leaf curl virus: nucleotide sequence and phylogenetic relationships. Molecular Plant Pathology On-Line ( http://www.bspp.org.uk/mppol/1999/0422lotrakul/paper.htm ), 1999.

[Endoscopic third ventriculostomy for management of obstructive hydrocephalus secondary to supratentorial intraventricular hematoma. Case report]

We report two cases of intraventricular hematoma with obstructive hydrocephalus. We perform endoscopic treatment of the hydrocephalus: aspiration of the hematoma associated with a third ventriculostomy. Both patients respectively aged 59 and 74 years had an obstructive hydrocephalus due to intraventricular hemorrage. The patient neurological status worsen at day 6 for patient No. 1 and at day 4 for patient No. 2. Endoscopic ventriculoscopy was performed respectively at day 6 and at day 5. Operatively, immediate vision was poor but was progressively improved by repetitive irrigation with Ringer-lactate (RL). Obstruction of the right Monro foramen by clot was observed. Introduction of the neuroendoscope into the third ventricle was possible after suction of the hematoma. Perforation of the floor of the third ventricle was performed after identification of the mammillary bodies and the infundibulum. Neurological status recovered within 10 days after surgery and the patients were referred to a medical unit. The patients were independent at home. The one-year MRI follow-up study showed a functional acqueduc in case 1 and a non-functional acqueduc in case 2 indicating in this case that the ventriculocisternotomy was useful. Intraventricular hematoma is not a contraindication for endoscopic third ventriculostomy. If possible, waiting for 6 or 5 days to allow the structuring of the blood clot and using large irrigation RL may facilitate the endoscopic procedure. This indication for endoscopic third ventriculostomy constitutes an alternative to external ventricular drainage which is significatively associated with complication (infection and obstruction). We cannot affirm that the removal of the clots and ventriculocisternostomy versus temporary external drainage avoids secondary hydrocephalus.

[Sphenoid sinus lymphoma. Case report and review of the literature]

A 64-year-old man presented to his general practitioner with an history of headaches and recent diplopia. Neuroradiological investigation showed a sphenoid sinus mass involving the sella and the clivus. Diagnosis of non-Hodgkin lymphoma was made via a transsphenoidal approach. The patient subsequently underwent a 6-month course of chemotherapy (M COPPA protocol) followed by 50 Gy locoregional radiotherapy. At three years follow-up the patient was in complete clinical and radiological remission. This case underscores the importance of thorough radiological work-up for accurate identification of tumor masses involving the pituitary fossa and provides an opportunity to review the literature on the management of this rare entity.

[Postoperative intracranial seeding of craniopharyngioma. Three case reports and a review of the literature]

Metastasis of craniopharyngioma is uncommon. Only 10 cases have been reported in the literature. In this report, we describe 3 patients who presented metastases following operative treatment of suprasellar craniopharyngioma. All 3 patients (ages: 32, 11, and 9 years) underwent radical excision of a supradiaphragmatic, retrochiasmatic craniopharyngioma by the right frontopterional approach. Resection was considered as total in all cases. All patients required hormone replacement therapy. Local recurrence was observed in only one case. Metastasis occurred along the surgical route in all three patients. The interval between surgery and metastasis was 5 and 3 years in the first two cases. The third patient presented two metastases: one in the temporal space at 3 years and another in the frontal space at 10 years. Repeat surgery was performed in 2 patients. The first case involved a lesion located in the right frontal space, and the second involved local recurrence and metastasis along the surgical route. The third patient was treated by puncture and radiation therapy for the temporal lesion and surveillance for the frontal lesions. No recurrence has been observed at 2 and 7 years after re-operation. Although rare, metastasis of craniopharyngioma has been reported up to 21 years after resection of the primary tumor. Metastasis often occurs along the surgical route, as in our 3 cases, but spreading to distant locations via cerebrospinal fluid has been observed. Regular follow-up is necessary, even after supposedly total resection.

[Dissemination of melanoma cells after anterior surgery of the cervical spine]

We describe a previously unreported complication after anterior surgery of the cervical spine for melanoma. Ten days after the surgical procedure, a 51-year-old man presented a huge cystic cervical metastasis along the surgical route. The pathophysiology and the surgical risk of the procedure are discussed.

[Metastatic meningioma to the first thoracic vertebral body. A case report and review of the literature]

This report describes a case of metastatic meningioma involving the first thoracic vertebral body in a 63-year-old woman. The patient was treated surgically 10 years earlier for a benign meningioma of the right parietal vault. Local recurrence was diagnosed in 1992. Despite the gamma-knife radiosurgery, recurrence required surgical treatment in 1999. Histological findings were compatible with atypical meningioma (grade II WHO). One year later, the patient presented left C8 cervicobrachial neuralgia. Investigation led to discovery of a D1 tumor that was a metastasis of the atypical intracranial meningioma. A resection of the vertebral T1 body with C7-T2 osteosynthesis was performed with an excellent recovery and no postoperative complication.

Relationship between composition and structure in chitosan-based hybrid films

Chitosan/poly(aminopropylsiloxane) hybrid films were obtained by blending 3-(aminopropyl)siloxane oligomers (pAPS) with chitosan (CHI). The pAPS oligomers were prepared by the sol-gel method starting from 3-(aminopropyl)triethoxysilane. These hybrids were characterized by chemical, spectroscopic and morphological methods. Scanning electron micrographs of hybrid films of different composition revealed an organized microscopic pattern suggesting the existence of systematic interactions among their components. Comparison of the thermal stabilities and X-ray diffraction patterns as well as FT-IR spectra of the films with those of the pure components revealed that nanocomposites were formed. Similar studies of films including lithium perchlorate, as a third component, showed that addition of certain amount of lithium ions affected the structure of the CHI/pAPS films. When addition of the lithium salt exceeded the homogeneous incorporation limit, a little excess generated anisotropically oriented patterns in the hybrid films.

[Burkitt lymphoma of the cavernous sinus. Apropos of a case]

Cavernous sinus lymphoma is a rare occurrence. We report a case of a 37-year-old woman who was admitted for an oculo-motor paresis and retro-orbital pain. CT scan and MRI disclosed a cavernous sinus tumor. A surgical biopsy was performed through a pterional approach and the histological diagnosis was a solitary primary Burkitt's lymphoma. Aggressive chemotherapy led to a complete and asymptomatic remission after a follow-up of 9 years. The mechanism of the primary localization in the cavernous sinus is discussed.

[Central neurocytoma revealed by intraventricular hemorrhage. A case report and review of the literature]

A case of intraventricular tumor presenting with intraventricular hemorrhage in a 38-year-old man is reported. Initial symptoms were an acute onset of headache with projectile vomiting. CT-scan revealed intraventricular hemorrhage. Cerebral angiography did not show any vascular malformation. MRI study, performed initially and several days after, disclosed and confirmed the presence of an intraventricular mass. The patient was operated on via a transfrontal route, and a complete tumor removal was achieved. Pathological examination was consistent with a central neurocytoma. Two similar cases from the literature are discussed with respect to differential diagnosis and practical management considerations.

Stress fracture of the femoral neck in a child. Case report and review of the literature

Fatigue fractures generally appear in normal bone following increased repetitive activity or strenuous exercise, when imbalance occurs between applied force and elastic resistance. Femoral neck fatigue fractures are most common in athletes and young military recruits; such fractures in children with open physes are very rare. This paper reports a fatigue fracture of the femoral neck in an 8-year-old girl presenting with pain in the anterior aspect of the right thigh, of one month duration and without evidence of previous injury. Bed rest and relief of weight bearing are indicated for nondisplaced compression fractures. Surgical treatment is indicated for tension fractures. In most cases, the outcome is favorable, and complications are rarely reported.

Traumatic atlantoaxial rotatory dislocation with odontoid fracture: case report and review

STUDY DESIGN

A case of traumatic rotatory dislocation associated with odontoid fracture is reported.

OBJECTIVES

To report a rare case of traumatic rotatory dislocation associated with odontoid fracture, and to discuss the mechanism underlying spinal instability and management.

SUMMARY OF BACKGROUND DATA

This case is a cross between traumatic rotatory fixation and atlantoaxial rotatory dislocation. Classification of rotatory subluxation change after osteosynthesis of the odontoid process was undertaken.

METHODS

A 24-year-old man sustained head and cervical injury after jumping. A Type 2 odontoid fracture without displacement was noted.

RESULTS

Without further traumatic event, 1 month after injury, computed tomography scan showed posterior displacement of the odontoid fracture and Type 4 or B atlantoaxial rotatory luxation. After surgical fixation and reduction of the odontoid fracture, the rotatory subluxation classification changed and became Type 1 or A. Posterior C1-C2 arthrodesis was performed. The patient wore a Philadelphia cervical collar for 3 months and underwent physiotherapy.

CONCLUSIONS

As the pivot of rotatory subluxation changed after odontoid process osteosynthesis, posterior C1-C2 arthrodesis was performed. The patient probably could have been treated in a single-stage procedure using posterior C1-C2 transarticular fixation with bicortical interspinous graft.

Spontaneous vertex extradural hematoma: considerations about causes. Case report and review of the literature

A 36-year-old woman with an uneventful medical history was admitted to the emergency department following an initial generalized seizure. Neuroimaging workup disclosed a homogeneous mass at the vertex, which first was diagnosed as vertex meningioma. Anticonvulsant drug therapy was administered and the patient was discharged. Two months later the patient was examined in our neurosurgery department for additional therapeutic recommendations. A repeated neuroimaging examination showed considerable regression of the lesion. The findings on magnetic resonance imaging were consistent with those of a regressing extradural hematoma (EDH). A complete blood-coagulation study displayed no evidence of abnormality. Thorough questioning of the patient revealed no history of pericranial infection or head trauma occurring within the last 2 years. The final diagnosis was spontaneously occurring vertex EDH. In this report the authors describe the clinical and neuroimaging features of the case as well as the management strategy, and discuss etiological aspects within the context of a careful review of the literature.

Meningeal hemangiopericytoma: a retrospective study of 21 patients with special review of postoperative external radiotherapy

OBJECTIVE

To specify that postoperative radiotherapy is useful for preventing local recurrence and neuraxis recurrence of surgically treated meningeal hemangiopericytomas.

METHODS

We retrospectively studied 21 patients with meningeal hemangiopericytoma who were followed in our department during a 34-year period. In 17 patients, the meningeal hemangiopericytoma was intracranial, and in 4 there was an intradural extramedullary localization. These groups were studied separately.

RESULTS

Of the 17 patients with intracranial hemangiopericytoma, all underwent surgery; 8 also underwent radiotherapy (5,000-6,400 rads) (Group I), and 9 did not (Group II). The mortality rate was zero for Group I patients and 55% for Group II. The mean local recurrence rate was 52% (12.5% in Group I and 88% in Group II; P < 0.05). Neuraxis recurrences occurred in two patients in Group II, and none occurred in Group I (P = 0.4). Peripheral metastasis took place in two patients (22%) in Group II and in one patient (12.5%) in Group I (P = 0.5). Of the four patients with intradural extramedullary hemangiopericytoma, all underwent surgery. Two patients received 4000 rads of radiotherapy after intervention. No patient in this group had a recurrence.

CONCLUSION

For patients with intracranial meningeal hemangiopericytoma, surgical removal followed by external radiotherapy reduced the risk of local recurrence. It was not demonstrated that postoperative radiotherapy protected against neuraxis metastasis. Radiotherapy did not protect against peripheral metastasis, which can occur up to several years after the first operation. It appears that radiotherapy after surgery for local or neuraxis recurrence did not avoid further recurrence. Radiosurgery is indicated for recurrent tumors measuring less than 25 mm in greatest diameter. For intradural extramedullary localizations, the value of postoperative radiotherapy is more questionable.

[Atlanto-axial lateral mass osteoarthritis. Three case reports and review of the literature]

This report describes three cases of symptomatic unilateral C1-C2 mass osteoarthritis. The patients were all female aged 67, 62 and 59 years. One patient had a history of rheumatoid arthritis. Unilateral occipital pain was the main symptom. Neuroradiological work-up included open mouth anteroposterior radiograph, flexion/extension lateral radiograph of the cervical spine, CT scan with coronal and sagittal reconstruction and MRI. Findings allowed differential diagnosis with tumoral or infectious disease of upper cervical spine and ruled out C1-C2 instability. CT scan and MRI permitted precise operative planning by determining the course of vertebral artery in the C1 and C2 vertebrae. Two patients were treated by CT scan guided steroid injection. The third patient was treated by C1-C2 arthodesis after failure of conservative treatment.

[Intracavernous epidermoid cyst. Case report and review of the literature]

We report an unusual case of epidermoid cyst located in the cavernous sinus. Only two cases of epidermoid cyst of the cavernous sinus have been reported in the literature. In 1995, a 61-year-old man experienced diplopia, which resolved spontaneously. Imaging findings, particularly magnetic resonance, showed a cavernous sinus tumor. The MR appearance was compatible with epidermoid cyst. Since the patient was, at the time, asymptomatic, we proposed clinical and MR surveillance. In 1999, he developed a right III palsy with V1 and V2 hypoesthesia. The size of the cavernous tumor had increased on the control MR and the patient was operated via an extradural temporopterional approach through the Dolenc lateral triangle. We used a neuroendoscope to perform total resection of the tumor cyst. The extradural approach to the cavernous sinus and use of a neuroendoscope allowed complete removal of the cyst and shortened postoperative care. The patient was discharged on day 5 after surgery. These techniques provided a good view of the tumor without orbitozygomatic or zygomatic osteotomy. The 30 neuroendoscope allowed visual control of tumor removal that was better than a direct microscope view.

Management of brain stem abscess

The brain stem is an uncommon site of a brain abscess. Such lesions were invariably fatal before 1974, when the arrival of computed tomography and magnetic resonance imaging improved the prognosis. This new case with a good result shows the usefulness of early diagnosis, careful clinical and radiological monitoring and combined medical and surgical management. A child 2 1/2 years of age was admitted to the department of neurosurgery for diagnosis and treatment of a brain stem lesion. The clinical context and discovery of an intrabronchial foreign body, as well as neuroradiological investigations, suggested a diagnosis of brain stem abscess. Initial treatment with broad spectrum antibiotics with good cerebral penetration was associated with an increase in the size of the abscess and clinical worsening. Stereotactic aspiration of lesion was performed by a transpeduncular approach under CT guidance and general anaesthesia. Secondary thoracotomy enabled removal of an intrabronchial needle. After evacuation, in spite of failure to identify the organism, neurological deficit resolved rapidly and the lesion no longer appeared on CT. Management of a brain abscess always includes antibiotics. They must cover the organisms most often encountered in brain abscesses and have good cerebral penetration. Medical treatment seems to suffice for small abscesses. A brain stem abscess with rapid clinical signs, together with current neuroradiogical diagnostic techniques, enables early discovery of such abscesses when they are still small. Treatment of brain stem abscesses includes primary antibiotic therapy, then stereotaxic drainage when there is any diagnostic doubt, poor clinical tolerability or antibiotic resistance.

[Occipital condyle fractures and clivus epidural hematoma. Case report]

A 47-year-old woman presented with a rare case of epidural hematoma of the clivus. The patient had bilateral occipital condyle fractures (a comminuted fracture on the right side, an avulsion fracture on left side and a lower clivus fracture). On admission the patient was tetraparetic with left abducens palsy. Preoperative imaging showed no atlanto-axial or occipito-atlantal dislocation. The patient was operated with a posterior approach. An occipital craniectomy with C1 laminectomy was achieved without atlanto-occipital fusion. Two years after the trauma, the patient had mild left hemiparesis but was able to walk normally. Head motion was normal, but just mildly decreased by pain in flexion and extension. Imaging control did not show any occipito-atlantal instability. We describe the imaging features allowing precise diagnosis and discuss the management of a rare entity: bilateral occipital condyle fractures and epidural hematoma of the clivus.

[Arachnoid cysts of the middle fossa and associated subdural hematoma. Three case reports and review of the literature]

BACKGROUND AND PURPOSE

We report 3 cases of subdural hematoma associated with arachnoid cyst of the middle fossa, and discuss the treatment.

METHODS

Three males aged 33, 63 and 68 were treated in our institution. Before this event the cyst was asymptomatic and unknown. Magnetic resonance imaging was the most contributive radiologic exam. Surgical procedure was limited to subdural hematoma evacuation. The internal wall of subdural hematoma was opened in all cases.

RESULTS

The clinical outcome was good for all patients. The CT or MRI scan follow-up 3 months later revealed nearly total disappearance of subdural hematoma for 2 out of 3 cases. For one patient the volume of arachnoid cyst decreased.

CONCLUSIONS

We propose subdural hematoma drainage without any specific treatment (shunt or fenestration) of the arachnoid cyst, for this category of patient.

Etiology of Sweet Potato Chlorotic Dwarf Disease in Argentina

Chlorotic dwarf (CD), the most important disease in the sweet potato-producing regions of Argentina, is caused by the synergistic combination of two aphid-transmitted potyviruses with a whitefly-transmitted crinivirus. Sweet potato feathery mottle virus, sweet potato mild speckling virus, and a crinivirus (serologically related to sweet potato chlorotic stunt virus) were associated with CD. The synergistic combination of these three viruses reproduced the disease.

Imaging features in combined atlantoaxial and occipitoatlantal rotatory subluxation: a rare entity. Case report

The authors report a new case of combined atlantoaxial and occipitoatlantal rotatory subluxation in a 17-year-old girl. They describe the clinical and imaging features of this rare entity. An occiput-C2 arthrodesis was performed.

[A free meningioma of the cauda equina]

We report an unusual case of a cauda equina meningioma occurring in a young girl. This tumor was neurinoma-like. No meningeal attachment was identified in the neuroradiological study and during its microsurgical removal.

In vivo efficacy of oral and intralesional administration of 2-substituted quinolines in experimental treatment of new world cutaneous leishmaniasis caused by Leishmania amazonensis

The antileishmanial efficacies of 2-n-propylquinoline, chimanines B and D, 2-n-pentylquinoline, 2-phenylquinoline, 2-(3,4-methylenedioxyphenylethyl) quinoline, and two total alkaloidal extracts of Galipea longiflora were evaluated in BALB/c mice infected with Leishmania amazonensis or Leishmania venezuelensis. Animals were treated for 4 to 6 weeks postinfection with a quinoline by the oral route at 50 mg/kg of body weight twice daily for 15 days or by five intralesional injections at intervals of 4 days with a quinoline at 50 mg/kg of body weight. The reference drug, N-methylglucamine antimonate (Glucantime), was administered by subcutaneous or intralesional injection (regimens of 14, 28, or 56 mg of pentavalent antimony [Sbv] per kg of body weight daily). Twice-daily oral treatment with chimanine B at 50 mg/kg resulted in a decrease in lesion weight by 70% (P < 0.001) and a decrease in the parasite loads by 95% (P < 0.001). Five injections of chimanine B at intervals of 4 days reduced the lesion weight by 74% and the parasite loads in the lesion by 90% compared with the values for the group of untreated mice. Subcutaneous administration of N-methylglucamine antimonate at 28 mg of Sbv kg per day for 15 days reduced the parasite burden by 95% (P < 0.001), and five intralesional injections at the same concentration reduced the parasite burden by 96% (P < 0.001). Other 2-substituted quinolines, 2-n-propylquinoline administered by the oral and intralesional routes, 2-phenylquinoline administered by the oral route, 2-n-pentylquinoline administered by intralesional injection, and two total alkaloidal extracts of G. longiflora administered by the oral route, had intermediate effects. These findings suggest that chimanine B may be chosen as a lead molecule in the development of oral therapy against leishmaniasis.

Characterization of Paraguayan Trypanosoma cruzi strains isolated from acute patients of Chagas disease

Five Paraguayan Trypanosoma cruzi strains, isolated from acute chagasic patients, were studied by their behavior in BALB/c mice, metacyelogenesis, bio-metry of metacyclic forms and lectin agglutination. Early and intermediate parasitemic peaks were observed and the strains did not show high virulence. Metacyclogenesis capacity was not higher than 50% in all cases and there were no considerable differences in the biometry. They all belong to WGA-type strains according to the lectin agglutination assays except for one strain that agglutinated with WGA and PNA lectins. Although previous schizodeme analysis of these strains showed rather homogeneous profiles, biological features were quite heterogeneous.

[The antihypertensive response to prazosin, a selective vascular alpha blocker. A multicenter study]

The efficacy and safety of oral prazosin was assessed in 108 ambulatory mild (91-104 mmHg diastolic pressure) to moderate (104-114 mmHg) essential hypertensive patients. After a 2 week no-drug control period, prazosin, 2, 4, 8 or 10 mg per day was given in 2 weeks periods as needed to obtain control of blood pressure. A seating diastolic pressure of < or = 90 mmHg was defined as adequate response. Satisfactory blood pressure response was obtained in 86% of patients, with doses of 4 mg or less in 70%. Treatment results were not related to initial blood pressure level, but obese patients were more resistant to drug effect (p < 0.05). Heart rate and laboratory parameters did not change. Adverse effects, mainly headache, dizziness and palpitations, were noticed in 46 patients (43%) and occurred with the lower dose in 78% of them. Adverse effects were slight or moderated and lasted from 1 day to 2 weeks in most patients. Treatment was discontinued in 2 patients, one because of persistent dizziness which was promptly relieved after stopping the drug and another due to syncope occurring immediately after a dose increase. We conclude that oral prazosin at low doses is an effective and well-tolerated drug which should be considered in the treatment of mild to moderate hypertension.