Behavioral and electroantennogram responses of plum curculio, Conotrachelus nenuphar, to selected noxious plant extracts and insecticides

Behavioral and electroantennogram responses of plum curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), adults were tested for several methanolic plant extracts and organically approved insecticides. Plant extracts were evaluated for their potential as antifeedants or oviposition deterrents. These extract responses were also compared to those elicited by the non-neurotoxic, organic irritant-insecticide kaolin clay. Both sexes of plum curculio exhibited antennal response as measured by electroantennogram, which ranged from 0.2 to 1.1 mV, to plant extracts and the organic irritant/insecticide, with the greatest response to the extract of rough cocklebur, Xanthium strumarium L. (1.1 mV). No choice tests were conducted to compare feeding and oviposition by plum curculio on untreated apples or on apples treated with one of the extracts or the insecticide. The insecticide pyrethrum and extracts of X. strumarium and greater burdock, Arctium lappa L., significantly reduced feeding. Also, pyrethrum, A. lappa, Humulus lupulus L. (common hop), X. strumarium, and Verbascum songaricum Schrenk extracts completely inhibited egg deposition. In no-choice assays, the effects of kaolin clay with incorporated plant extracts on plum curculio feeding and oviposition were monitored as complementary tests. A. lappa-kaolin, H. lupulus-kaolin, and X. strumarium-kaolin mixtures significantly reduced the feeding of plum curculio compared to the control or kaolin clay alone. Each of the plant extract-kaolin mixtures evaluated, with the exception of Bifora radians Bieberstein (wild bishop), completely inhibited plum curculio oviposition as compared to controls.

Can we eliminate placebo in ALS clinical trials?

BACKGROUND

Previous studies concluded that the decline in strength in patients with amyotrophic lateral sclerosis (ALS) is a linear function. If so, a patient's natural history might serve as the control, instead of placebo, in a clinical trial.

METHODS

A placebo-controlled ALS clinical trial included a natural history phase, followed by a 6-month treatment phase. Each patient's forced vital capacity (FVC) score and maximal voluntary isometric contraction (MVIC) raw scores were measured monthly, standardized, and averaged into megascores. For 138 patients, the arm, leg, FVC, arm+leg combination, and arm+leg+FVC combination megascore slopes during the natural history phase and during the placebo phase were compared.

RESULTS

The mean slope of megascores during the natural history phase and the mean slope during the placebo phase were not different for the arm, leg, and arm+leg megascores, but were different for the FVC and arm+leg+FVC combination megascores.

CONCLUSIONS

Natural history controls may be useful in ALS exploratory trials that use arm megascore slope as the primary outcome measure. However, there are distinct limitations to the use of natural history controls, so that Phase 3 ALS clinical trials require placebo controls.

A preliminary evaluation of a prospective study of pulmonary function studies and symptoms of hypoventilation in ALS/MND patients

There is still no consensus as to which physiologic marker should be used as a trigger for the initiation of non-invasive positive pressure ventilation (NPPV) in patients with amyotrophic lateral sclerosis (ALS). Current practice parameters recommend that the decision to begin treatment be based upon forced vital capacity (FVC) measurements. A prospective, randomized study was performed in 20 ALS patients who had an FVC of 70-100%. Patients received baseline assessments including: ALS functional rating scale-respiratory version (ALSFRS-R), pulmonary symptom scale, Short form 36 (SF-36), FVC%, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and nocturnal oximetry. Patients were randomized to receive NPPV based upon nocturnal oximetry studies suggesting oxygen desaturation <90% for one cumulative minute ("early intervention") or a FVC <50% ("standard of care"). At enrollment, there was no significant correlation between FVC% and the ALSFRS-R, symptom score, MEP, MIP, or duration of nocturnal desaturation <90%. An increase in the vitality subscale of the SF-36 was demonstrated in 5/6 patients randomized to "early intervention" with NPPV. Our data indicate that FVC% correlates poorly with respiratory symptoms and suggests that MIP and nocturnal oximetry may be more sensitive measures of early respiratory insufficiency. In addition, intervention with NPPV earlier than our current standard of care may result in improved quality of life.

Brachial amyotrophic diplegia: a slowly progressive motor neuron disorder

OBJECTIVE

To describe a sporadic motor neuron disorder that remains largely restricted to the upper limbs over time.

BACKGROUND

Progressive amyotrophy that is isolated to the upper limbs in an adult often suggests ALS. The fact that weakness can remain largely confined to the arms for long periods of time in individuals presenting with this phenotype has not been emphasized.

METHODS

We reviewed the records of patients who had a neurogenic "man-in-the-barrel" phenotype documented by examination at least 18 months after onset. These patients had severe bilateral upper-extremity neurogenic atrophy that spared lower-extremity, respiratory, and bulbar musculature.

RESULTS

Nine of 10 patients meeting these criteria had a purely lower motor neuron disorder. During follow-up periods ranging from 3 to 11 years from onset, only three patients developed lower-extremity weakness, and none developed respiratory or bulbar dysfunction or lost the ability to ambulate.

CONCLUSION

Patients presenting with severe weakness that is fully isolated to the upper limbs, without pyramidal signs, may have a relatively stable variant of motor neuron disease.

Chronic cryptogenic sensory polyneuropathy: clinical and laboratory characteristics

BACKGROUND

Chronic sensory-predominant polyneuropathy (PN) is a common clinical problem confronting neurologists. Even with modern diagnostic approaches, many of these PNs remain unclassified.

OBJECTIVE

To better define the clinical and laboratory characteristics of a large group of patients with cryptogenic sensory polyneuropathy (CSPN) evaluated in 2 university-based neuromuscular clinics.

DESIGN

Medical record review of patients evaluated for PN during a 2-year period. We defined CSPN on the basis of pain, numbness, and tingling in the distal extremities without symptoms of weakness. Sensory symptoms and signs had to evolve for at least 3 months in a roughly symmetrical pattern. Identifiable causes of PN were excluded by history, physical examination findings, and results of laboratory studies. We analyzed clinical and laboratory data from patients with CSPN and compared findings in patients with and without pain.

RESULTS

Of 402 patients with PN, 93 (23.1%) had CSPN and stable to slowly progressive PN syndrome. These patients presented with a mean age of 63.2 years and a mean duration of symptoms of 62.9 months. Symptoms almost always started in the feet and included distal numbness or tingling in 86% of patients and pain in 72% of patients. Despite the absence of motor symptoms at presentation, results of motor nerve conduction studies were abnormal in 60% of patients, and electromyographic evidence of denervation was observed in 70% of patients. Results of laboratory studies were consistent with axonal degeneration. Patients with and without pain were similar regarding physical findings and laboratory test abnormalities. Only a few patients (<5%) had no evidence of large-fiber dysfunction on physical examination or electrophysiologic studies. All 66 patients who had follow-up examinations (mean, 12.5 months) remained ambulatory.

CONCLUSIONS

Cryptogenic sensory polyneuropathy is a common, slowly progressive neuropathy that begins in late adulthood and causes limited motor impairment. Isolated small-fiber involvement is uncommon in this group of patients. Management should focus on rational pharmacotherapy of neuropathic pain combined with reassurance of CSPN's benign clinical course.

Multifocal acquired demyelinating sensory and motor neuropathy: the Lewis-Sumner syndrome

We report 11 patients with multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy, defined clinically by a multifocal pattern of motor and sensory loss, with nerve conduction studies showing conduction block and other features of demyelination. The clinical, laboratory, and histological features of these patients were contrasted with those of 16 patients with multifocal motor neuropathy (MMN). Eighty-two percent of MADSAM neuropathy patients had elevated protein concentrations in the cerebrospinal fluid, compared with 9% of the MMN patients (P < 0.001). No MADSAM neuropathy patient had elevated anti-GM1 antibody titers, compared with 56% of MMN patients (P < 0.01). In contrast to the subtle abnormalities described for MMN, MADSAM neuropathy patients had prominent demyelination on sensory nerve biopsies. Response to intravenous immunoglobulin treatment was similar in both groups (P = 1.0). Multifocal motor neuropathy patients typically do not respond to prednisone, but 3 of 6 MADSAM neuropathy patients improved with prednisone. MADSAM neuropathy more closely resembles chronic inflammatory demyelinating polyneuropathy and probably represents an asymmetrical variant. Given their different clinical patterns and responses to treatment, it is important to distinguish between MADSAM neuropathy and MMN.

Myasthenia gravis activities of daily living profile

The authors have developed an MG activities of daily living (ADL) profile (MG-ADL)-a simple eight-question survey of MG symptoms. In 254 consecutive encounters with established MG patients, the authors compared scores from the MG-ADL to the quantitative MG score (QMG)-a standardized, reliable scale used in clinical trials. The mean MG-ADL score was 4.89+/-3.63. The mean QMG score was 10.80+/-5.70. Pearson's correlation coefficient was 0.583 (p < 0.001). The MG-ADL is an easy-to-administer survey of MG that correlates well with the QMG and can serve as a secondary efficacy measurement in clinical trials.

The exercise test in Andersen syndrome

BACKGROUND

Andersen syndrome is a rare form of periodic paralysis (PP) associated with dysmorphic features and potentially fatal cardiac dysrhythmias. To date, no electrodiagnostic abnormalities have been reported that can be used to confirm the presence of PP in this condition.

OBJECTIVES

To determine if the exercise test could be used to confirm the diagnosis of PP in Andersen syndrome. To evaluate the exercise test as a means to assess neuromuscular status during treatment.

METHODS

We performed the exercise test on 2 patients with Andersen syndrome. In 1 patient, we used a modified version of the test to document responsiveness to treatment with tocainide.

RESULTS

Studies in both patients demonstrated a progressive decline in the compound muscle action potential amplitude after exercise that was characteristic of the phenomenon seen in other forms of PP. In 1 patient, improvement in interattack strength and a reduction in the number of attacks of weakness correlated with improvement in the test results.

CONCLUSIONS

Our cases demonstrate that the exercise test can confirm the diagnosis of PP in Andersen syndrome. A modified version of exercise testing may also be considered as an objective method for documenting treatment responses in PP.

Distal myasthenia gravis

Myasthenia gravis (MG) characteristically involves ocular, bulbar, and proximal extremity muscles. Distal extremity muscles are typically spared or less prominently involved. The authors performed a retrospective chart review of MG patients treated at two university-based neuromuscular clinics. From a total population of 236, nine patients (3%) had distal extremity weakness exceeding proximal weakness by at least one Medical Research Council grade during their illness. Hand muscles, particularly finger extensors, were involved more frequently than were distal leg and foot muscles.

Magnetic resonance imaging of muscle in amyotrophic lateral sclerosis

OBJECTIVE

To characterize leg muscle abnormalities in patients with ALS using MRI, and to correlate MRI with standard neurologic measures of motor neuron dysfunction.

METHODS

Eleven ALS patients were studied twice (once at baseline and again after 4 months) and compared with eight normal control subjects. MRI data of the lower extremities were compared with tibialis anterior compound muscle action potential amplitude (CMAPa) and foot dorsiflexion maximal voluntary isometric contraction (MVIC).

RESULTS

Muscle MRI was abnormal by visual inspection in six of 11 patients. The mean muscle T1 time and muscle volume were not different in patients compared with normal control subjects (p > 0.1). However, the mean T2 times were increased in the patients compared with normal control subjects (p = 0.009). T1 times did not correlate with CMAPa or MVIC. Muscle volume correlated with MVIC (r = 0.73 to 0.78, p < 0.02) but not with CMAPa (p > 0.05). There was a strong negative correlation (r < -0.8, p < or = 0.01) between muscle T2 time and MVIC and CMAPa. Also, the change in T2 relaxation time correlated with the change in CMAPa as the disease progressed (r = -0.63, p = 0.037).

CONCLUSION

Of the MRI characteristics studied, T2 relaxation time was the best indicator of motor neuron dysfunction and may have a role in objective evaluation of motor neuron dysfunction.

Primary hyperparathyroidism and ALS: is there a relation?

BACKGROUND

An association between primary hyperparathyroidism (PHP) and amyotrophic lateral sclerosis (ALS) has been noted; however, a causal relation between these disorders has not been confirmed.

PATIENTS/METHODS

We report five patients (three men, two women) meeting El Escorial criteria for ALS who also had PHP. In three patients, the diagnosis of PHP was made during the laboratory evaluation for motor neuron disease, and in one patient, the diagnosis of PHP preceded the onset of weakness by 5 months and in another by 2 years. Serum calcium levels in all five patients were elevated, ranging from 11.2 to 12.8 mg/dL (normal, <10.4 mg/dL), as were levels of parathyroid hormone (PTH).

RESULTS

All five patients underwent parathyroid adenoma resection with subsequent normalization of serum calcium and PTH levels. Each patient had progressive weakness resulting in death 1 to 3 years following parathyroidectomy.

CONCLUSION

Resection of parathyroid adenomas in patients meeting El Escorial criteria for ALS did not alter the course of ALS. PHP and ALS appear to be coexisting but unrelated disorders.

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease with evidence of both anterior horn cell and corticospinal tract degeneration. The incidence of ALS is 1 to 2.5 cases per 100,000 population and the disease occurs primarily in adult life. The etiology of sporadic ALS remains unknown, although 5 to 10% of cases are familial. The diagnosis of ALS requires the presence of both upper and lower motor neuron findings and progressive motor dysfunction. Several theories regarding the pathogenesis of ALS have emerged including glutamate excitotoxicity, free radical oxidative stress, neurofilament accumulation, and autoimmunity. Clinical trials involving antiglutamate agents, antioxidants, immunosuppressants, and growth factors have shown no substantial benefit in slowing progression, with death usually occurring 2 to 5 years following the onset of symptoms. The management of ALS patients requires a multidisciplinary team that can provide the numerous medical and physical interventions necessary to treat weakness and fatigue, bulbar dysfunction, spasticity and pain, depression, and respiratory failure.

Toward earlier diagnosis of amyotrophic lateral sclerosis: revised criteria. rhCNTF ALS Study Group

We modified the World Federation of Neurology (WFN) diagnostic criteria for ALS to facilitate early diagnosis and used these criteria for enrollment of ALS patients in a clinical trial. The criteria developed required lower motor neuron (LMN) involvement in at least two limbs and upper motor neuron involvement in at least one region (bulbar, cervical, or lumbosacral). The EMG finding of fibrillation potentials was required for evidence of LMN involvement. Electrodiagnostic studies, neuroimaging, and laboratory studies were also used to exclude disorders that might mimic ALS. Using these criteria, the diagnosis of ALS was made at a mean time of 9.7 months from onset of symptoms, which compares favorably with the 12-month period cited in the literature. Using clinical assessment at completion of the trial, the diagnosis of ALS was believed to be accurate in those patients entered in the trial. However, pathologic confirmation of the diagnosis of ALS was not obtained. Based on our preliminary experience, we propose that these ALS diagnostic criteria will facilitate early diagnosis of ALS. Future studies should prospectively compare these criteria with the WFN criteria currently in use.

Acetylcholine receptor antibodies in the Lambert-Eaton myasthenic syndrome

Two patients were initially diagnosed with myasthenia gravis with elevated titers of acetylcholine receptor antibodies. Features including weakness that normalized with sustained contraction, areflexia, autonomic symptoms, and low-amplitude baseline compound muscle action potentials with abnormal increments following brief exercise and high-frequency repetitive stimulation, however, suggested that these patients had Lambert-Eaton myasthenic syndrome. One patient had antibodies directed against presynaptic calcium channels, confirming the diagnosis. The second patient was seronegative for these antibodies but had elevated titers of antistriated muscle antibodies. This shows that serologic studies can conflict with clinical and electrodiagnostic findings in patients with Lambert-Eaton syndrome. These cases also point out that acetylcholine receptor antibodies are not necessarily diagnostic of myasthenia gravis in patients with Lambert-Eaton syndrome. Instead, these antibodies could represent a nonpathogenic epiphenomenon.

Antibody panels in idiopathic polyneuropathy and motor neuron disease

We prospectively evaluated patients with idiopathic polyneuropathy (PN) and motor neuron disease (MND) with commercial antibody (Ab) panels. Patients with sensorimotor PN received a "sensorimotor neuropathy profile" [3-sulfated glucuronyl paragloboside (SGPG)/myelin-associated glycoprotein (MAG), GM1, asialo-GM1, GD1b, Hu, sulfatide]. Motor neuropathy or MND patients underwent a "motor neuropathy profile" (SGPG/MAG, GM1, asialo-GM1). Seven of 78 patients (9.0%) with sensorimotor PN and 3 of 44 patients (6.8%) with MND had abnormal panels. None of 60 patients with axonal sensory or sensorimotor PN had antisulfatide Ab. Seven of 13 patients (54%) with multifocal motor neuropathy had abnormal panels, with 6 seropositive to GM1. We found abnormal Ab panels in fewer than 10% of patients with idiopathic sensorimotor PN and MND. Moreover, abnormal Ab tests often did not relate to the clinical context. Our data do not support the use of commercial Ab panels in the evaluation of patients with idiopathic PN or MND.

A brief quality-of-life measure for ALS clinical trials based on a subset of items from the sickness impact profile. The Syntex-Synergen ALS/CNTF Study Group

We previously demonstrated a significant relationship (P<0.0001) between maximum voluntary isometric contraction (MVC) plus pulmonary function scores (the Tufts Quantitative Neuromuscular Exam Combination Megascore (TQNE CM)), and the Sickness Impact Profile (SIP) in a cohort of 524 ALS patients. Because the 136-item SIP questionnaire can be difficult to administer in this population, we examined SIP subscales and clinically derived item sets in relation to the TQNE CM in an effort to define a briefer measure of quality of life for use in clinical trials. Two 'Mini-SIP' indices performed as well as the overall SIP in reflecting the impact of muscle weakness on ALS patients' quality of life: a combination of two SIP subscales ('SIP-33'), and a 19-item set of questions independently chosen by a panel of ALS specialists ('SIP/ALS-19'). Either index potentially could be useful in ALS clinical trials. The SIP/ALS-19 is currently being used in a National ALS data base, providing an opportunity to evaluate its utility prospectively against other QOL measures in ALS patients.

Reliability of maximal voluntary isometric contraction testing in a multicenter study of patients with amyotrophic lateral sclerosis. Syntex/Synergen Neuroscience Joint Venture rhCNTF ALS Study Group

Maximal voluntary isometric contraction (MVIC) is becoming widely used for monitoring disease progression in amyotrophic lateral sclerosis (ALS). We evaluated the variability of MVIC in a large multicenter (29 sites) drug trial in ALS. Intra- and interrater variability were assessed twice during the 19-month study. Intrarater reliability increased from the first to the second test, approaching the reliability reported for a single experienced clinical evaluator, but interrater reliability did not. Multiple clinical evaluators in a single site increased the variability of MVIC measurements. Rigorous quality assurance standards and monitoring of clinical evaluators should be incorporated into the design of multicenter studies using MVIC, since low variability is necessary to detect a modest treatment effect.

Electrophysiologic findings in multifocal motor neuropathy

We performed detailed electrophysiologic studies on 16 patients with clinically defined multifocal motor neuropathy and found a wide spectrum of demyelinating features. Only five patients (31%) had conduction block in one or more nerves. However, in 15 patients (94%) at least one nerve showed other features of demyelination. We also noted a significant degree of superimposed axonal degeneration in 15 patients. Eight patients (50%) had individual nerves with pure axonal injury, despite the presence of demyelinating features in other nerves. Antiganglioside antibodies were elevated in four of five patients with conduction block and five of 11 patients without conduction block. We conclude that multifocal motor neuropathy is characterized electrophysiologically by a wide spectrum of axonal and demyelinating features. Diagnostic criteria requiring conduction block may lead to underdiagnosis of this potentially treatable neuropathy.

Evaluation of neurologic function in Gulf War veterans. A blinded case-control study

OBJECTIVE

To determine whether Gulf War-related illnesses are associated with central or peripheral nervous system dysfunction.

DESIGN

Nested case-control study.

PARTICIPANTS

Twenty-three veterans with factor analysis-derived syndromes (the cases), 10 well veterans deployed to the Gulf War (the deployed controls), and 10 well veterans not deployed to the Gulf War (the nondeployed controls).

METHOD

With investigators blinded to group identities, participants underwent objective neurophysiological, audiovestibular, neuroradiological, neuropsychological, and blood tests.

MAIN OUTCOME MEASURES

Evidence of neurologic dysfunction.

RESULTS

Compared with the 20 controls, the 23 cases had significantly more neuropsychological evidence of brain dysfunction on the Halstead Impairment Index (P=.01), greater interside asymmetry of the wave I to wave III interpeak latency of brain stem auditory evoked potentials (P=.02), greater interocular asymmetry of nystagmic velocity on rotational testing, increased asymmetry of saccadic velocity (P=.04), more prolonged interpeak latency of the lumbar-to-cerebral peaks on posterior tibial somatosensory evoked potentials (on right side, P=.03, and on the left side, P=.005), and diminished nystagmic velocity after caloric stimulation bilaterally (P values range from .02 to .04). Cases (n=5) with syndrome 1 ("impaired cognition") were the most impaired on brain stem auditory evoked potentials (P=.005); those (n=13) with syndrome 2 ("confusion-ataxia") were the most impaired on the Halstead Impairment Index (P=.006), rotational testing (P=.01), asymmetry of saccadic velocity (P=.03), and somatosensory evoked potentials (P< or =.01); and those (n=5) with syndrome 3 ("arthro-myo-neuropathy") were the most impaired on caloric stimulation (P< or =.01).

CONCLUSIONS

The 3 factor-derived syndromes identified among Gulf War veterans appear to represent variants of a generalized injury to the nervous system.

Placebo-controlled trial of gabapentin in patients with amyotrophic lateral sclerosis. WALS Study Group. Western Amyotrophic Lateral Sclerosis Study Group

We designed a phase II trial to evaluate the efficacy of gabapentin in slowing the rate of decline in muscle strength of patients with amyotrophic lateral sclerosis (ALS) and to assess safety and tolerability. Gabapentin (800 mg) or placebo was administered t.i.d. in a randomized, double-blinded, placebo-controlled, trial for 6 months. We enrolled 152 patients at eight sites in the United States. The primary outcome measure was the slope of the arm megascore, the average maximum voluntary isometric strength from eight arm muscles standardized against a reference ALS population. A secondary outcome measure was forced vital capacity. Slopes of arm megascores for patients on gabapentin were compared with slopes of those taking placebo using a two-way ANOVA. We observed a nonstatistically significant trend (p = 0.057-0.08) toward slower decline of arm strength in patients taking gabapentin compared with those taking placebo (mean difference 24%, median 37%). We observed no treatment effect on forced vital capacity. Gabapentin was well tolerated by patients with ALS. These results suggest that further studies of gabapentin in ALS are warranted.

Toxicity and tolerability of recombinant human ciliary neurotrophic factor in patients with amyotrophic lateral sclerosis

We examined the toxicity of both single and multiple subcutaneous injections of recombinant human ciliary neurotrophic factor (rhCNTF) in 72 patients with ALS, in doses ranging from 2 to 100 micrograms/kg. Adverse events were generally dose related and ranged from mild to severe. The tolerability of daily subcutaneous rhCNTF was equivalent to placebo at doses < or = 5 micrograms/kg/day. At higher doses, anorexia, weight loss, reactivation of herpes simplex virus (HSV1) labialis/stomatitis, cough, and increased oral secretions occurred.

The effect of a muscle wrap on nerve healing in a rat model

Sixty Sprague-Dawley rats were studied to determine if peripheral nerve healing could be enhanced by translocation of an injured segment of sciatic nerve from an interfascial to an intramuscular environment. Group 1 (n = 12) were unoperated controls; Group 2 (n = 12) were sham-operated; Group 3 (n = 12) sustained an acute, double-crush injury to the sciatic nerve; and Group 4 (n = 12) sustained the same acute, double-crush injury as in Group 3, but the injured segment of nerve was transposed intramuscularly. All animals had sciatic function indices (SFI) computed at weekly intervals. At 2 weeks, Group 4 appeared to have improved gait function (SFI), compared to Group 3 (-39.7 vs. -56.4, p < 0.08). The experiment was repeated for Groups 3 and 4 using two groups of six additional rats each. The data were collected three times for each rat in the second experiment. No statistically significant differences in return of gait function or in nerve conduction evaluation could be demonstrated between the two study groups. From the results of this study, it appears that an intramuscular location does not enhance nerve recovery, compared to an interfascial location.

Inclusion body myositis: clinical and pathological boundaries

Inclusion body myositis, polymyositis, and dermatomyositis are three distinct categories of inflammatory myopathy. Some authorities commented on the selective early weakness of the volar forearm muscles, quadriceps, and ankle dorsiflexors in inclusion body myositis. The most important feature distinguishing inclusion body myositis from the other two inflammatory myopathies is the lack of responsiveness to immunosuppressive treatment. Although most patients with inclusion body myositis have characteristic muscle biopsy findings, some cannot be distinguished histologically early from polymyositis. Predicting responsiveness to immunosuppressive medications, independent of muscle histology, would be valuable to clinicians. We retrospectively reviewed the pattern of weakness and other clinical features of 46 patients newly diagnosed with either inclusion body myositis, polymyositis, or dermatomyositis. Asymmetrical muscle weakness with prominent wrist flexor, finger flexor, and knee extensor involvement was specific for inclusion body myositis and unresponsive polymyositis. Male sex, lower creatine kinase levels, slower rate of progression, and peripheral neuropathy were also more common in inclusion body myositis and unresponsive polymyositis than in responsive polymyositis and dermatomyositis patients. Repeat muscle biopsy in 2 patients in the unresponsive polymyositis group demonstrated histological features of inclusion body myositis. We suspect that patients with clinical features of inclusion body myositis but lacking histological confirmation may nonetheless have inclusion body myositis. Our study supports the recently proposed criteria for definite and possible inclusion body myositis.

Isolated neck extensor myopathy: a common cause of dropped head syndrome

We report four patients with "dropped head syndrome," a recently described nonprogressive myopathy characterized by severe neck extensor weakness. This relatively benign condition may be confused with more ominous neuromuscular disorders that also present with prominent neck weakness. We compared clinical and laboratory data from the patients with dropped head syndrome with findings from patients with head drop caused by other neuromuscular conditions. Patients with "isolated neck extensor myopathy," a term we prefer to "dropped head syndrome," could be readily identified with electrophysiologic, radiographic, and histologic studies.

A placebo-controlled trial of recombinant human ciliary neurotrophic (rhCNTF) factor in amyotrophic lateral sclerosis. rhCNTF ALS Study Group

Preclinical investigations indicated that recombinant human ciliary neurotrophic factor (rhCNTF) may have potential as therapy for amyotrophic lateral sclerosis (ALS). We evaluated the safety and efficacy of rhCNTF in a prospective, double-blind, placebo-controlled trial in 570 patients with ALS. Patients were randomized to receive 0.5, 2, or 5 micrograms/kg/day rhCNTF, or placebo, for 6 months. The primary efficacy end point was the change from baseline to the last on-treatment value of a combination megascore for limb strength (maximum voluntary isometric contraction) and pulmonary function. Secondary end points included individual arm and leg megascores, pulmonary function tests, an activities-of-daily-living outcome measure, and survival. The four treatment groups were similar at baseline with respect to age, sex, disease duration, and muscle strength values. At all doses tested, rhCNTF had no beneficial effect on the primary or secondary end points. Certain adverse events, as follows, appeared to be dose related: injection site reactions, cough, asthenia, nausea, anorexia, weight loss, and increased salivation. There was an increased number of deaths at the highest dose level. rhCNTF had no beneficial effect on any measure of ALS progression. There were increased adverse events in the 5 micrograms/kg group and increased deaths.

Tomaculous neuropathy: a clinical and electrophysiological study in patients with and without 1.5-Mb deletions in chromosome 17p11.2

Tomaculous neuropathy is the descriptive term for the "sausagelike" swellings of myelin characteristic of hereditary neuropathy with liability to pressure palsies (HNPP). A 1.5-Mb deletion in chromosome 17p11.2 is present in the majority but not all cases of HNPP. We reviewed the clinical and electrophysiological features of 18 patients with tomaculous neuropathy and compared these features between patients with and without the typical large deletion. Patients presented with a variety of pressure-induced nerve palsies and brachial plexopathies. Two patients presented with generalized symmetric sensorimotor polyneuropathies. Four patients were older than their respective probands but were as yet asymptomatic. Nerve conduction studies demonstrated prolonged distal latencies out of proportion to slowing of conduction velocities, suggesting a distally accentuated myelinopathy. DNA analysis revealed the 1.5-Mb deletion in all the familial cases and in 3 of the sporadic patients. The clinical and electrophysiological features were similar between patients with and without the 1.5-Mb deletion in chromosome 17p11.2.

Denervated human skeletal muscle: MR imaging evaluation

Because determination of neurologic integrity after severe limb trauma is crucial in patient care, the authors assessed magnetic resonance (MR) imaging as a tool to map denervated motor units of skeletal muscle in patients with traumatic peripheral neuropathy. Denervation was confirmed in 22 patients with use of electromyography, surgery, or both. MR imaging was performed with moderately T1- and T2-weighted spin-echo and short-tau inversion-recovery (STIR) sequences. MR imaging was unreliable in depicting acute denervation. Muscles of patients with subacute denervation had prolonged T1 and T2, which contributed to conspicuous hyperintensity on STIR images. Chronically denervated muscles showed marked atrophy, variable changes on STIR images, and conspicuous fatty infiltration on T1-weighted images. Normal variants in motor unit anatomy were seen in denervated muscle volumes outside the expected distribution of the injured nerve. MR imaging is promising for the noninvasive mapping and monitoring of denervated muscle in subacute and chronic phases of peripheral neuropathy.

Locomotor system assessment by muscle magnetic resonance imaging

Clinical evaluation of the locomotor system has long been hampered by difficulty in assessing the morphologic and functional integrity of skeletal muscles. Diagnostic imaging represents a major advance in the diagnosis and management of patients with locomotor dysfunction through the possibility of probing beyond overlying soft tissues to identify muscle lesions, determine their extent, characterize their composition, direct invasive procedures, and monitor therapies. Magnetic resonance imaging (MRI) appears to be the most promising of available imaging methods, because of its great sensitivity to changes in muscle water distribution and fat content. Also, it can distinguish between individual deep and superficial muscles. Serial evaluations of many muscles are practical because of the safety of MRI. While the cost effectiveness in the workup of locomotor dysfunction remains to be determined, the scientific and practical clinical information now available merits further investigation by clinicians and radiologists alike. The purpose of this review is to describe the potential role of skeletal muscle MRI in evaluating the locomotor system.

Effects of soils, fertilizers and stocking rates on pastures and beef production on the Wallum of South-East Queensland. 4. Budgetary appraisals of fertilizer and stocking rates

Comparative budgeting techniques have been applied to the results of a grazing experiment in which the effects of different stocking rates and maintenance levels of fertilizer were examined. The experiment was carried out on grass/legume pastures in the coastal lowlands of south-east Queensland. The economic appraisal is of an investment project based on fattening purchased store cattle. Extrapolative trends have been fitted to the pattern of pasture production emerging from the first six years of an experimental period, to enable the life of the project to extend over a twenty year period. The recent sharp increases in the price of superphosphate and potassium fertilizer have had a marked effect on intensive beef production on improved pastures which is illustrated in this analysis. Pasture maintenance costs (principally fertilizer inputs) appear as the largest component of annual operating costs in most systems. The budgets indicate that at July 1973 fertilizer prices the positive internal rates of return of the various grazing systems range from 4.2 per cent to 13.2 per cent at a beef price of $0.77 kg-1 dressed weight. The highest return was obtained from a system in which 250 kg ha-1 single superphosphate and 63 kg ha-1 potassium chloride were applied annually and at a stocking rate of 1.65 beasts ha-1. These returns are reduced to a high of 10.4 per cent when 1974 fertilizer prices are incorporated. At beef prices of $0.66 kg-1, all systems but one were found to have negative internal rates of return. Assuming beef prices of $0.88 kg-1, most treatments were associated with positive internal rates of return, generally well above 10 per cent, ranging up to 20 per cent. Most of the calculations, by excluding land values from the budgeted cash flows, assume that unimproved land is already available at no charge to the investor. A series of supplementary budgets indicate the level of returns that could be expected if unimproved land commanded values of up to $200 ha-1.

Effects of soils, fertilizers and stocking rates on pastures and beef production on the Wallum of south-eastern Queensland. 2. Liveweight change and beef production

Animal production was measured over a six-year period from grass-legume pastures receiving different maintenance rates of phosphorus and potassium fertilizers, and continuously grazed at stocking rates of 1.23, 1.65 and 2.47 beasts ha-1. The pastures consisted of the grasses Chloris gayana, Digitaria decumbens, Paspalum dilatatum and P. commersonii and the legumes Desmodium intortum, D. uncinatum, L otononis bainesii, Macrop tilium lath yroides and Trifolium repens. Annual applications of 250 kg ha-1 superphosphate (9.6 per cent P) significantly increased animal production above applications of 125 kg ha-1 superphosphate, but there were no significant effects of increase in level of applied potassium (as KCI) beyond 63 kg ha-1. The greatest liveweight gain per hectare was obtained at a stocking rate of 2.47 beasts ha-1 but rate of liveweight change was more variable than at the other stocking rates. Conversely, daily liveweight gains per head and rate of turnoff were greatest at 1.23 beasts ha-1. Both stocking rates and levels of superphosphate affected quality of carcase produced, and there was a significant positive correlation of liveweight gain and legume content of the pastures.

Effects of soils, fertilizers and stocking rates on pastures and beef production on the Wallum of south-eastern Queensland. 1. Botanical composition and chemical effects on plants and soils

A complex pasture mixture was grazed by cattle at three stocking rates (1.23, 1.65 and 2.47 beasts a hectare) at Beerwah, south-eastern Queensland over six years. There were four fertilizer treatments involving two rates of superphosphate and three of KCl. On the basis of species frequencies, the seven major soil types on the area fell into two groups, the podzolic soils in one and the humic gleys in another. The podzolics were favoured by Chloris gayana, Desmodium intortum, D. uncinatum and Lotononis bainesii, whereas Paspalum dilatatum and Trifolium repens were more frequent on the humic gleys. The light stocking rate favoured Paspalum commersonii, Digitaria decumbens and both Desmodium species. At the high stocking rate P. dilatatum, T. repens and L. bainesii were more prominent, as were weeds in general. Application of KCl had no effect on botanical composition but the K content of soils and plants increased with increasing levels of application. As the superphosphate rate was increased, the proportion of all sown species except P. dilatatum and L. bainesii increased and the weed content decreased. Over time, the legume content in all plots decreased, weeds increased and the grass content remained about the same. The effects were more marked at low rates of superphosphate and high stocking rate. There was a lower legume content and a higher weed content in winter than in summer, but soils and treatments had similar effects in both seasons. Compared with virgin soils, those under fertilized pastures for eight years contained more organic C, available P, K and Ca, total N, and Zn and Fe.

The value of Nauru rock phosphate as a source of phosphorus for some tropical pasture legumes

Using soils known to be grossly deficient in phosphorus, and with a basal dressing of sulphur (and other deficient nutrients) plants were grown in pots and in the field with single superphosphate or Nauru rock phosphate. The plants fell into two groups, those that gave moderate yield responses to rock phosphate as compared with superphosphate (Lotononis bainesii, Stylosanthes guyanensis, Centrosema pubescens, Indigofera spicata, and Medicago sativa) and those whose response to rock phosphate was poor (Desmodium uncinatum and Phaseolus lathyroides). In no case was the response to rock phosphate as good as that to superphosphate, even when twice as much phosphorus, in the form of rock phosphate, was applied. The residual value of rock phosphate was low with Desmodium, high with Lotononis, but never as high as that of superphosphate.

Grazing trials on the Wallum of south-eastern Queensland. 1. A comparison of four pastures

Four pastures, based respectively on Paspalm dilatatum, P. commersonii, P. plicatulum, and Digitaria decumbens, were grazed by beef cattle at Beerwah from 1959 to 1965. Mean annual liveweight gain was 244 lb an acre, and the best pastures produced 262 lb an acre. The pattern of liveweight change was of gain in summer and early autumn (mean 0.99 !b a head a day), no change in late autumn and winter, and a higher rate of gain in spring and early summer (mean 1.55 lb a day). This pattern was related partly to the changing condition of the pasture and partly to animal factors. Only on the Paspalum plicatulum pasture was there a weight loss in winter. The legume content of the pastures was low, only 13 per cent, and this had a major influence on the results. The main legumes were Desmodium uncinatum, Lotononis bainesii, and Trifolium repens. Nitrogen content of the pastures was below 1 per cent in autumn and winter, and at these seasons the quantity of digestible crude protein was probably insufficient to maintain animals in positive nitrogen balance. Quality improved in spring, and, although the total available dry matter was low, animals thrived at that time. It seems clear that the measurements made on these pastures did not fully reflect the diet of the grazing animals.

Grazing trials on the Wallum of south-eastern Queensland. 2. Complex mixtures under common grazing

Eight legumes and eight grasses in complex mixtures were grazed in common on a welldrained soil at Beerwah, south-east Queensland, for eight years. The aim was to study persistence and productivity and also to follow live weight changes in the cattle. Of the legumes, Trifolium repens, Desmodiam uncinatum, and Lotononis bainesii persisted and spread into other plots ; Centrosema pubescens, Medicago sativa, Phaseolus laithyroides, Trifolium incarnatum, and Desmodium sandwicense were not persistent. Among the grasses Paspalum notatum, P. dilatatum, Digitaria decumbens, and Chloris gaylana all persisted and spread ; P. plicatulum persisted but spread little, Panicum maximum var. trichoglme was reduced to trace proportions, while Paspalam conzmersonii and Brachiaria mutica finally disappeared. Legume content of the pastures was 25 to 30% and weed content about 20%. Annual and seasonal amounts of dry matter on offer are presented. Cattle gained weight for 38 weeks but made no gains for 14 weeks in winter. Once the pastures were well developed, the annual live weight gain was approximately 300 lb an acre. Nitrogen content of the pasture was satisfactory from spring to autumn.

The effect of urea and cutting treatments on the production of Pangola grass in south-eastern Queensland

Urea at rates of 100, 300, and 500 lb N an acre a year, cutting intervals of 4, 8, and 12 weeks, and cutting heights of 2 inches and G inches were applied factorially to a Pangola grass sward in south-eastern Queensland (lat. 275) over a period of two years. Nitrogen applications increased the yields of dry matter and nitrogen, the nitrogen content and nitrogen recovery ; the responses were marked, significant, and quadratic. Responses to cutting intervals were significant and linear, but cutting height had only a slight effect and this was restricted to yield of dry matter. Maximum yields of dry matter were 21,000 lb an acre a year, of nitrogen 200 lb an acre a year, and the mean yield of nitrogen was 45 per cent of that applied. Growth was markedly seasonal ; production of dry matter in tops varied from about 1 lb an acre a day in winter to over 100 lb an acre a day in summer. It is considered that the major physical limitations to growth in this region are water shortage in summer and low temperatures in winter. Little growth was made when the average screen minimum temperature was less than 52�F, or the average night temperature less than 58�F, the maximum having less influence.

Lotononis bainesii Baker — a legume for sub-tropical pastures

Lotononis bainesii is a prostrate, fine stemmed, small leaved, stoloniferous perennial legume, suitable for pasture mixtures in parts of the sub-tropics and tropics. It prefers moist, friable soils, on which it withstands heavy graying. It is highly palatable and non-toxic to stock and is frost tolerant but virus susceptible. Heavy grazing in late summer reduces virus attack and ensures green growth through the winter. Reproduction is by seed or by vegetative means. The species combines well with a number of pasture grasses. Yields of L. bainesii exceeding one ton of dry matter per acre have been obtained in mid-summer on grazed grass-legume mixtures, and yields of 1/4 ton per acre are common. The mean nitrogen content is approximately 2.9 per cent.

Pasture studies on the coastal lowlands of Subtropical Queensland. III. The nutrient requirements and potentialities of Desmodium uncinatum and white clover on a lateritic podzolic soil

Nutrient deficiencies in a lateritic podzolio soil typical of the eucalypt ridges of the coastal lowlands of south-eastern Queensland, as measured by the responses of Desmodium uncinatum (Jacq.) DC, and white clover (Trifolium repens L.), are reported and discussed. The soil is grossly deficient in phosphorus and nitrogen; other severely limiting nutrients are calcium, copper, sulphur, and, somewhat later in growth, potassium. Molybdenum and zinc are less limiting to growth, but additions of them may be needed as pastures become older. It is possible that boron may also be i11 short supply for some species. White clover responded well to additions of copper, but Desmodium did not. It would also appear that white clover requires more calcium than D. uncinatum. The results for this soil are in general agreement with those obtained on the gley soils in the region. The two soils are sufficiently different in their water relations for white clover to thrive on the gleys (wet soils) and to be short-lived on the podzolic (dry) soils where it is subject to attack by nematodes. D. uncinatum shows promise as a pasture legume on both soil types. This is the first recorded use of D. uncinatum as a pasture legume under field conditions. The results quoted are from ungrazed trials; however, in other experiments D. uncinatum has been maintained under intermittent and at times very close grazing by sheep. Yields of approximately 2 tons of dry matter/acre/year have been obtained once this species is well established. The nitrogen content of the material is 3.2–3.6 per cent. These figures indicate that this species, which has persisted for up to 4 years on each soil type, can be made a valuable component of subtropical coastal pastures.

Pasture studies on the coastal lowlands of subtropical Queensland. I. Introduction and initial plant nutrient studies

A general description of the underdeveloped coastal lowlands of southern Queensland is given. Location, soils, vegetation, climate, present use, and problenls confronting investigators are dealt with. Plant nutrient studies on a low humic gley at Beerwah and a humic gley soil at Glasshouse Mountains are reported. For both soils the plant responses are qualitatively similar but they differ in degree. The limiting nutrients for plant growth are phosphorus, nitrogen, calcium, potassium, copper, zinc, molybdenum, and boron in descending order of importance. For an efficiently nodulated legume, added nitrogen is not required. Soil chemical analyses and plant analyses show that the nutrients to which responses are obtained are in extremely low supply in the soils. The effect of over-liming on these soils is discussed in relation to change of soil pH, and availability of copper and zinc. Deficiency symptoms of calcium, potassium, and copper for certain species are discussed and observations made on their intensification through the addition of other major nutrients to the soil. Maximum plant growth on these soils can only be obtained if all limiting nutrients are supplied. This may explain in part the failure of earlier attempts to establish agriculture on these soils.

Pasture studies on the coastal lowlands of subtropical Queensland. II. The interralation of legumes, rhizobium, and calcium

The soils of the coastal lowlands of southern Queensland are deficient in many nutrients, including phosphorus, calcium, and nitrogen. Initial attempts to grow clovers on these soils failed because available strains of Rhizobium were not effective and the plants suffered acutely. When useful strains of bacteria were obtained this lack of nitrogen was largely overcome. Until effective strains of Rhizobium are associated with legume hosts, the legumes do not, under local conditions, respond normally to nutrients. In particular, responses to calcium may be quite abnormal. The response of a legume to calcium can be used in some cases as a measure of the effectiveness of the associated Rhizobium on these soils. Effective strains of Rhizobium were successfully applied to existing stands of white clover on three soil types both in the form of inoculated soil and in aqueous suspension.