New Mexico and the southwestern US are affected by a unique population of tomato spotted wilt virus (TSWV) strains.

Tomato spotted wilt virus (TSWV) is an important pathogen of many ornamental, greenhouse and agronomic crops worldwide. TSWV also causes sporadic problems in a number of crops in New Mexico (NM). Nucleocapsid gene sequences obtained from six different crop species across the state over four different years were used to characterize the NM TSWV population. This analysis shows that NM is affected by a unique TSWV population that is part of larger independent population present in the southwestern US. This population likely arose due to geographic isolation and is related to other TSWV populations from the US, Spain, and Italy.

First Report of Anthracnose of Sunflower Sprouts Caused by Colletotrichum acutatum in New Mexico.

In December 2011, edible sunflower sprouts (Helianthus annus) of two different commercially grown cultivars (Sungrown and Tiensvold) exhibiting stem and cotyledon lesions were submitted to the New Mexico State University Plant Clinic for disease diagnosis. The sample originated from an organic farm in Santa Fe County where the grower utilizes a small indoor growing facility. Stem lesions were elongate, reddish brown, and often constricted, resulting in stem girdling. Lesions on the cotyledons were dark brown with tan centers and round to irregular in shape. In some cases, the entire cotyledon was blighted. Fungal hyphae were observed on some lesions using a dissecting microscope. Colletotrichum acutatum was isolated from stem and cotyledon lesions when symptomatic tissue was plated on water agar. Conidia were fusiform ranging from 6.4 to 18.4 µm long and 2.1 to 5.1 µm wide and averaged 11.9 µm × 3.4 µm. Spores were measured from cream-colored colonies produced on acidified potato dextrose agar. PCR amplification and sequence analysis of 5.8S ribosomal DNA and internal transcribed spacers I and II was performed using primers ITS4 and ITS6 (2). An amplification product of approximately 600 base pairs in size was directly sequenced (GenBank Accession No. JX444690). A BLAST search of the NCBI total nucleotide collection revealed a 99% identity to multiple C. acutatum (syn: C. simmondsii) isolates. Four isolates were identified as C. acutatum based on morphological characteristics and DNA analysis. Koch's postulates were performed using four isolates of the pathogen and the two commercial sunflower cultivars (Sungrown and Tiensvold) originally submitted for disease analysis. Sunflower seeds were imbibed in distilled water for 24 h then sewn into peat plugs. Prior to seed germination, 5 ml of a C. acutatum spore solution (1 × 106/ml) from each isolate was applied to five peat plugs using an atomizer. Control plants were inoculated with distilled water and otherwise treated identically. Both sunflower cultivars were inoculated with each isolate of the pathogen and the test was replicated twice. The sewn peat plugs were incubated for 5 days at 21°C and 50% relative humidity. Symptoms similar to the original samples were present on 100% of the sprouts after 5 days. PCR and sequence analysis performed on cultures obtained from lesions showed a 100% match to the original New Mexico isolates fulfilling Koch's postulates. In an indoor organic facility, such as the one in NM, this disease has the potential to be very difficult to manage and the potential to infect a high percentage of the crop resulting in significant economic losses. To our knowledge, this is the second report of C. acutatum on sunflower sprouts in the United States (1) and the first report in New Mexico. References: (1) S. T. Koike et al. Plant Dis. 93:1351, 2009. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

First Report of Phytophthora nicotianae on Bulb Onion in the United States.

Phytophthora nicotianae (synonym P. parasitica) Breda de Haan was isolated from recently harvested onion bulbs (Allium cepa) in cold storage from a commercial field in southern New Mexico. Deteriorating, water-soaked tissue from the center of four bulbs was plated onto water agar and incubated at room temperature. After 72 h, cultures of Phytophthora (identified by the presence of coenocytic hyphae and papillate sporangia) were isolated and transferred to V8 agar amended with ampicillin (250 mg/liter), rifampicin (10 mg/liter), and pimaricin (0.2% wt/vol). Isolates were identified as P. nicotianae based on morphological characteristics and DNA analysis. Sporangia were sharply papilliate, noncaducous, and ovoid to spherical. The average sporangium size was 45.9 × 39.9 µm with a length-to-width ratio of 1.15. Clamydospores, both terminal and intercalary, were spherical to ovoid and averaged 37.2 × 35.2 µm (2). PCR from whole-cell extracts was performed on four cultured isolates from the infected onion tissue using previously described primers ITS4 and ITS6, which amplify the 5.8S rDNA and ITS1 and ITS2 internal transcribed spacers (1,4). A band of approximately 890 bp was amplified and directly sequenced (GenBank Accession No. HQ398876). A BLAST search of the NCBI total nucleotide collection revealed a 100% similarity to multiple P. nicotianae isolates previously sequenced (1). To confirm the pathogenicity of the isolates, onion seedlings were inoculated with 25 ml of P. nicotionae zoospore solution (15,000 zoospores/ml). Necrosis of leaf tissue and seedling death was observed 5 days postinoculation. P. nicotianae was reisolated from the infected onion seedlings and the ITS region was sequenced to confirm its identity. P. nicotianae was previously reported in bulb onion from Australia, Taiwan (Formosa), and Zimbabwe (Rhodesia) (2). P. nicotianae was reported on bunching onions (A. fistulosum) in Hawaii in 1989 (3). Onions are an important crop in New Mexico with a total production value of 47 million dollars in 2008 (NM Agriculture Statistics 2008). This discovery of a potentially significant postharvest disease poses a threat to the onion industry in New Mexico. To our knowledge, this is the first report of P. nicotianae in bulb onion in the United States and the first report of P. nicotianae in New Mexico on any crop. References: (1) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (2) D. C. Erwin and O. K. Ribeiro. Page 56 in: Phytophthora Diseases Worldwide. The American Phytopathological Society, St Paul, MN, 1996. (3) R. D. Raabe et al. Information Text Series No. 22. University of Hawaii. Hawaii Inst. Trop. Agric. Human Resources, 1981. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

First Report of Buckeye Rot Caused by Phytophthora nicotianae in Tomato in New Mexico.

Phytophthora nicotianae Breda de Haan was isolated from turning tomato fruit (Solanum lycopersicum L.) in August 2010 from a garden in central New Mexico. Symptoms typical of buckeye rot including brown, water-soaked, necrotic lesions with concentric rings were observed on three tomato fruit. Tissue from each fruit was surface sterilized and plated onto water agar and incubated at room temperature. After 72 h, colonies of Phytophthora (identified by the presence of coenocytic hyphae and papillate sporangia) were found and subcultured by hyphal tips to V8 agar amended with ampicillin (250 mg/liter), rifampicin (10 mg/liter), and pimaricin (0.2% wt/vol). The isolates of Phytophthora were identified as P. nicotianae based on morphological characteristics and DNA analysis. Sporangia were sharply papillate, noncaducous, and ovoid to spherical. The average sporangium size was 44.5 × 35.5 µm with a length-to-width ratio of 1.26. Chlamydospores, both terminal and intercalary, were spherical to ovoid and averaged 38.9 × 37.5 µm. PCR amplification and sequence analysis on three isolates from the infected tomato tissue was performed using primers ITS4 and ITS6 that amplify the 5.8S rDNA and ITSI and ITSII internal transcribed spacers (1,2). A band of approximately 890 bp was amplified and directly sequenced (GenBank Accession No. HQ711620). A BLAST search of the NCBI total nucleotide collection revealed a 100% similarity to multiple P. nicotianae isolates previously sequenced. Pathogenicity tests with sequenced P. nicotianae isolates were performed to confirm virulence on tomato fruit. Tomatoes were surface sterilized with 95% ethanol and 0.1 ml of a P. nicotianae zoospore suspension (10,000 zoospores/ml) or sterile water was pipetted onto the surface of the tomato fruit. After 5 days in a humidity chamber, all three inoculated tomatoes had expanding water-soaked, circular lesions and the negative control showed no disease symptoms. P. nicotianae was successfully reisolated from the inoculated tomato tissue and the ITS region was sequenced to confirm its identity. Although the disease has been reported in many other states since the early 1900s, to our knowledge, this is the first report of P. nicotianae causing disease on tomato in New Mexico. References: (1) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

First Report of Septoria Leaf Spot of Pistachio in New Mexico.

In September of 2008, a Septoria sp., the causal agent of Septoria leaf spot of pistachio (Pistacia vera L.) was isolated from leaf lesions in an orchard in southern New Mexico. Tree fruit and nut crops including pistachios are becoming an increasingly important part of New Mexico's agricultural industry with total cash receipts of $103 million in 2007 (3). This preliminary positive for Septoria prompted a survey of pistachio-growing counties in the state. The surveyed orchards accounted for approximately 30% of the pistachio acreage in New Mexico. Results indicated that all five pistachio-growing counties had orchards infected with a Septoria sp. Isolates of Septoria from leaf lesions were identified as Septoria pistaciarum Caracc. based on the following symptoms and morphological characteristics of the fungus: leaf lesions were usually circular, 0.5 to 3 mm in diameter, and contained many pycnidia per lesion; pycnidia were dark, ostiolate, and measured 101 to 255 × 69 to 133 µm; and conidia were hyaline, filiform, contained 3 to 9 septa, and measured 3 to 4 × 60 to 149 µm. Most orchards were only mildly affected. In severe cases, hundreds of leaf lesions were present on diseased leaves; large sections of the leaves turned tan and some trees defoliated prematurely. This widespread occurrence of Septoria leaf spot in New Mexico in 2008 suggests that the disease had already been present in the state for several years. A higher average rainfall in the summer of 2008 provided excellent conditions for disease development. Because of the high amounts of inoculum currently present in New Mexico orchards, Septoria leaf spot may emerge as a recurring disease problem for pistachio producers. This disease was first reported in the United States in Texas in 1971 and was also reported in Arizona in 1989 (1,2,4). To our knowledge, this is the first report of Septoria leaf spot of pistachio in New Mexico. References: (1) A. Chitzandis. Ann. Inst. Phytopathol. Benaki 10:29, 1956. (2) J. L. Maas et al. Plant Dis. Rep. 55:72, 1971. (3) New Mexico Agricultural Statistics, Department of Agriculture, 2007. (4) D. J. Young and T. Michailides. Plant Dis. 73:775, 1989.

Xylella fastidiosa Detected in New Mexico in Chitalpa, a Common Landscape Ornamental Plant.

Different strains of Xylella fastidiosa cause a variety of significant disease problems in agricultural and ornamental plants, including Pierce's disease in grapes, oleander leaf scorch, pecan bacterial leaf scorch, and alfalfa dwarf disease. X. fastidiosa has never been reported in New Mexico but is known to exist in surrounding states (California, Arizona, and Texas). During the summer of 2006, several chitalpa (Chitalpa tashkinensis) hybrid trees with leaf scorch symptoms and branch die back were observed in Las Cruces, NM and they tested positive for X. fastidiosa by ELISA. Additional samples from these plants and others were analyzed by ELISA, PCR (2), and cultured on XfD2 medium (1). Known positive and negative oleander samples from Arizona were included as controls. Fifteen of thirty tested chitalpa were PCR and ELISA positive, indicating that they were infected with X. fastidiosa. Bacterial colonies that were PCR positive were also recovered from 10 of the XF positive samples that were plated. DNA sequences of PCR products amplified from chitalpa and isolated bacterial colonies (GenBank Accession Nos. EF109936 and EF109937) were identical to each other, 97% similar to X. fastidiosa strain JB-USNA, and 96% similar to the Temecula 1 strain. Independent ELISA testing (Barry Hill, California Department Food and Agriculture, Sacramento, CA) confirmed our ELISA and PCR results. On the basis of these results, we conclude that X. fastidiosa is present in New Mexico and that the common landscape ornamental chitalpa is a host for X. fastidiosa. Additional work is required to determine if X. fastidiosa is pathogenic to chitalpa and to examine the relevance of this potential X. fastidiosa reservoir to agricultural production in New Mexico and other areas where chitalpa is grown. References: (1) R. P. P. Almeida et al. Curr. Microbiol. 48:368, 2004. (2) M. R. Pooler et al. Lett. Appl. Microbiol. 25:123, 1997.

Upper aerodigestive tract cancers in former employees at an iron and steel works.

Local concern about numbers of laryngeal cancer cases led to an investigation of the incidence of upper aerodigestive tract (UAT) cancer in an industrial cohort. Males (n = 11 470) who had been directly employed at an iron and steel works in northern England at any time between January 1960 and site closure in September 1983 were followed up for UAT cancers until December 1998. The incidence of UAT and laryngeal cancer was compared to the general population of the region via indirect standardization. Fifty-two members of the cohort developed a UAT cancer during 1960-1998. There were no more UAT cancers than expected [standardized incidence ratio = 97, 95% confidence interval (CI) = 72-127], but slightly more laryngeal cancers than expected (standardized incidence ratio = 118, 95% CI = 78-171), although this estimate was less precise. The lack of complete work histories meant that relationships between cancer incidence and length of service or job categories could not be explored.

Blood pressure response to glucose potassium insulin therapy in patients with acute stroke with mild to moderate hyperglycaemia.

Insulin is neuroprotective in animal stroke models but its effects in acute stroke in humans are unknown. The Glucose Insulin in Stroke Trial (GIST-UK) is a randomised controlled trial investigating the benefits of maintaining euglycaemia in hyperglycaemic patients with acute stroke. Data are reported from a GIST-UK substudy which sought to determine the influence of glucose potassium insulin (GKI) infusion on blood pressure in acute stroke. All adult patients admitted to hospital with acute stroke with hyperglycaemia (plasma glucose 6.1-17 mmol/l) were potentially eligible. Randomised patients received either a GKI infusion (500 ml 10% glucose, 20 mmol potassium chloride, 16 units of insulin) or control therapy with 154 mmol/l (0.9%) saline at 100 ml/h for 24 hours. BM test strip glucose monitoring was performed 2 hourly, blood pressure monitoring 4 hourly, and plasma glucose sampling 8 hourly. Insulin concentration in the GKI infusate was altered according to test strip values to maintain test strip values between 4-7 mmol/l in the GKI group. Neurological impairment was determined using the European stroke scale (ESS). 145 patients were studied (73 GKI, 72 control). Mean systolic blood pressure was significantly lower during GKI infusion between 4 hours and 24 hours except at 8 hours. Median total ESS scores improved significantly between admission and day 7 in the GKI group (p<0.001) although there was no significant difference in total ESS score between groups at day 7. The significant reduction of systolic blood pressure in acute stroke associated with GKI therapy was not associated with neurological deterioration and may have been beneficial.

Glucose potassium insulin infusions in the treatment of acute stroke patients with mild to moderate hyperglycemia: the Glucose Insulin in Stroke Trial (GIST).

BACKGROUND AND PURPOSE: Hyperglycemia following acute stroke is strongly associated with subsequent mortality and impaired neurological recovery, but it is unknown whether maintenance of euglycemia in the acute phase improves prognosis. Furthermore, the safety of such intervention is not established. METHODS: In an explanatory, randomized, controlled trial to test safety, 53 acute (within 24 hours of ictus) stroke patients with mild to moderate hyperglycemia (plasma glucose between 7.0 and 17.0 mmol/L) were randomized to receive either a 24-hour infusion of 0.9% (154 mmol/L) saline or a glucose potassium insulin (GKI) infusion at 100 mL/h. The GKI consisted of 16 U human soluble insulin and 20 mmol potassium chloride in 500 mL 10% glucose. Blood glucose was measured every 2 hours with Boehringer Mannheim Glycaemie test strips, pulse and blood pressure were measured every 4 hours, and plasma glucose samples were taken every 8 hours. Insulin concentration in the GKI was altered according to BM glucose values. RESULTS: There were no statistically significant differences between the 2 groups at baseline. Twenty-five patients received GKI, 1 of whom required intravenous glucose for symptomatic hypoglycemia. Plasma glucose levels were nonsignificantly lower in the GKI group throughout the infusion period. Four-week mortality in the GKI group was 7 (28%), compared with 8 (32%) in the control group. CONCLUSIONS: GKI infusions can be safely administered to acute stroke patients with mild to moderate hyperglycemia producing a physiological but attenuated glucose response to acute stroke, the effectiveness of which remains to be elucidated.

Atrial fibrillation and cognitive function: case-control study.

Atrial fibrillation is an important and independent risk factor for cerebrovascular disease and vascular dementia. There is increasing evidence that atrial fibrillation is associated with an increased risk of asymptomatic or silent cerebral infarction and as a result may confer an increased risk of progressive cognitive impairment on a person. In this study we sought to determine whether this hypothesis could be explored in a prospective case controlled design. Twenty seven patients with non-valvular atrial fibrillation (NVAF) and no history of stroke, transient ischaemic attack, dementia, and thyrotoxicosis were compared with 54 age and sex matched controls in sinus rhythm. All cases underwent clinical examination, ECG, and psychological assessment using a battery of nine neuropsychological tests. Between group analysis and a comparison of mean test scores of paired controls with cases were undertaken. The presence of atrial fibrillation was consistently associated with poorer performances on all the subtests of the neuropsychological battery. There was no association between duration of atrial fibrillation and performance. These results provide evidence to justify further examination of the hypothesis in a larger prospective study to determine whether antithrombotic therapy may protect against cognitive decline in patients at maximal risk of silent cerebral ischaemia and associated cognitive decline.

The prevalence of hyperprolactinaemia and association with markers of autoimmune thyroid disease in survivors of the Whickham Survey cohort.

OBJECTIVE: Few data exist on the prevalence of hyperprolactinaemia in the community. This study was intended to determine the prevalence of hyperprolactinaemia in a sample closely matched to the current British population aged 38 years and over. DESIGN AND PATIENTS: The 1877 survivors at the 20-year follow-up of the Whickham Survey were a cross-sectional sample of the community aged 38 years and over. Serum was frozen and stored at -30 degrees C from 90% of the survivors (751 men, 924 women, median age 58 years (range 38 to 93 years)) who participated in the follow-up survey. MEASUREMENTS: Two years after the follow-up survey, serum prolactin concentrations were measured by ELISA/1 step sandwich assay (reference range < or = 600 mU/l in men and women). A repeat prolactin measurement was made in those subjects who had prolactin levels within the top 2.5% of men and women in this sample. RESULTS: At screening, 0.7% of the men and 2.5% of the women had serum prolactin levels greater than 600 mU/l. For men, 2.5% were above 400 mU/l. The prevalence of hyperprolactinaemia, if defined as greater than 400 mU/l in men and greater than 600 mU/l in women on repeat testing, was 1.4% in the men and 1.2% in the women. The aetiology in men was prolactin-raising drugs (n = 3), renal failure (n = 1), microprolactinoma (n = 1), and unknown (n = 2), and in women it was prolactin-raising drugs (n = 7), microprolactinoma (n = 1), and unknown (n = 1). Logarithmic transformation of serum prolactin concentrations produced Gaussian distributions with 95% reference ranges of 60-430 mU/l in men and 40-560 mU/l in women. No significant relationship was found in either sex between hyperprolactinaemia and age or evidence of autoimmune thyroid disease at either survey. In women, there was no association with age, distance beyond the menopause or duration of reproductive years but prolactin levels were slightly higher in those on oestrogen therapy (geometric mean prolactin 226 mU/l compared to 178 mU/l; t-test on log prolactin t = 3.79; P < 0.0001). CONCLUSIONS: This study has demonstrated that a gender-related reference range for serum prolactin is necessary. Pituitary pathology is not common and screening with measurement of serum prolactin is not warranted in middle-aged and elderly subjects. In asymptomatic subjects with modestly elevated serum prolactin levels (< 3 SD above the mean), extensive pituitary imaging and investigation is unwarranted. Autoimmune thyroid disease was not a significant cause of hyperprolactinaemia in this sample.

The incidence of diabetes mellitus in an English community: a 20-year follow-up of the Whickham Survey.

The original Whickham Survey documented the prevalence of diabetes and lipid disorders in a sample of 2779 adults aged 18 years and over, which matched the British population structure. The aim of the 20-year follow-up study was to determine the incidence and natural history of diabetes. Outcomes in terms of morbidity and mortality at follow-up were determined in over 97% of the original population. Ninety-four subjects had been identified and treated for diabetes since the first survey, including 17 subjects identified as having a fasting plasma glucose > or = 7.8 mmol l-1 at follow-up. The incidence of diabetes for the total population was 2.2 1000-1 year-1 (95% confidence interval 1.8, 2.6). The risk factors identified at first survey were corrected for age, cut-off at the 95 centile and entered into a log linear model. Those which strongly predicted development of diabetes in the total population were fasting blood glucose (odds ratio (OR) (with 95% confidence intervals) = 2.3 (1.5, 3.5)) and body mass index (OR = 2.2 (1.5, 3.3)) in men, and fasting blood glucose (OR = 2.6 (1.7, 4.1)) and fasting serum triglyceride (OR = 2.8 (1.8, 4.4)) in women. A logit model has enabled the calculation of the probability of developing diabetes 20 years later. It was the characteristics of becoming older such as obesity, hypertriglyceridaemia, and raised fasting blood glucose, rather than age itself, which were associated with the development of diabetes.

The development of ischemic heart disease in relation to autoimmune thyroid disease in a 20-year follow-up study of an English community.

The original Whickham Survey documented risk factors for cardiovascular disease and the prevalence of thyroid disorders in a sample of 2779 adults that closely matched the British population. A 20-year follow-up study has determined outcomes in terms of morbidity and mortality from ischemic heart disease in over 97% of the original survey population. Analysis of deaths from all causes and from ischemic heart disease showed no association with antithyroid antibody status identified at first survey. A multiple logistic regression using the development of ischemic heart disease in the total population at follow-up as the dependent variable found that the significant predictor variables for men were age, cholesterol, mean arterial blood pressure, smoking history, and skinfold thickness index. For women only age, cholesterol, and mean arterial blood pressure were significant. The presence of autoimmune thyroid disease, as defined by either hypothyroidism, positive antithyroid antibodies, or raised serum thyrotropin at first survey, was not significant. A retrospective cohort study of a subsample of women identified at first survey with positive antithyroid antibodies or raised serum thyrotropin and closely matched controls found no significant association with mortality or development of ischemic heart disease. There is no evidence from this study to suggest that evidence of autoimmune thyroid disease identified 20 years ago is associated with an increased risk of ischemic heart disease.

The incidence of thyroid disorders in the community: a twenty-year follow-up of the Whickham Survey.

BACKGROUND AND OBJECTIVE: The original Whickham Survey documented the prevalence of thyroid disorders in a randomly selected sample of 2779 adults which matched the population of Great Britain in age, sex and social class. The aim of the twenty-year follow-up survey was to determine the incidence and natural history of thyroid disease in this cohort. DESIGN, PATIENTS AND MEASUREMENTS: Subjects were traced at follow-up via the Electoral Register, General Practice registers, Gateshead Family Health Services Authority register and Office of Population Censuses and Surveys. Eight hundred and twenty-five subjects (30% of the sample) had died and, in addition to death certificates, two-thirds had information from either hospital/General Practitioner notes or post-mortem reports to document morbidity prior to death. Of the 1877 known survivors, 96% participated in the follow-up study and 91% were tested for clinical, biochemical and immunological evidence of thyroid dysfunction. RESULTS: Outcomes in terms of morbidity and mortality were determined for over 97% of the original sample. The mean incidence (with 95% confidence intervals) of spontaneous hypothyroidism in women was 3.5/1000 survivors/year (2.8-4.5) rising to 4.1/1000 survivors/year (3.3-5.0) for all causes of hypothyroidism and in men was 0.6/1000 survivors/year (0.3-1.2). The mean incidence of hyperthyroidism in women was 0.8/1000 survivors/year (0.5-1.4) and was negligible in men. Similar incidence rates were calculated for the deceased subjects. An estimate of the probability of the development of hypothyroidism and hyperthyroidism at a particular time, i.e. the hazard rate, showed an increase with age in hypothyroidism but no age relation in hyperthyroidism. The frequency of goitre decreased with age with 10% of women and 2% of men having a goitre at follow-up, as compared to 23% and 5% in the same subjects respectively at the first survey. The presence of a goitre at either survey was not associated with any clinical or biochemical evidence of thyroid dysfunction. In women, an association was found between the development of a goitre and thyroid-antibody status at follow-up, but not initially. The risk of having developed hypothyroidism at follow-up was examined with respect to risk factors identified at first survey. The odds ratios (with 95% confidence intervals) of developing hypothyroidism with (a) raised serum TSH alone were 8 (3-20) for women and 44 (19-104) for men; (b) positive anti-thyroid antibodies alone were 8 (5-15) for women and 25 (10-63) for men; (c) both raised serum TSH and positive anti-thyroid antibodies were 38 (22-65) for women and 173 (81-370) for men. A logit model indicated that increasing values of serum TSH above 2mU/l at first survey increased the probability of developing hypothyroidism which was further increased in the presence of anti-thyroid antibodies. Neither a positive family history of any form of thyroid disease nor parity of women at first survey was associated with increased risk of developing hypothyroidism. Fasting cholesterol and triglyceride levels at first survey when corrected for age showed no association with the development of hypothyroidism in women. CONCLUSIONS: This historical cohort study has provided incidence data for thyroid disease over a twenty-year period for a representative cross-sectional sample of the population, and has allowed the determination of the importance of prognostic risk factors for thyroid disease identified twenty years earlier.

Colorectal carcinoma: do elderly patients present differently?

A cohort of patients with a histological diagnosis of colorectal carcinoma was enrolled prospectively. All subjects were interviewed by one observer using a structured questionnaire. One hundred and fifty 'young' (under 70 years) and 123 'elderly' (70 years or more) subjects formed the study sample. The elderly patients did not present more frequently as emergencies than the young, but were more often referred to medical or geriatric rather than surgical units (p < 0.01). There was no difference in median overall delay from symptom onset to histological diagnosis between the age groups (19.5 weeks in each). Symptomatic anaemia and nonspecific symptoms were more often the presenting complaint in the elderly subjects (p < 0.05). On direct questioning, there were no differences in symptom reporting with respect to age group for subjects with colonic cancer. For rectal cancer the following symptoms were more common in the young group: tenesmus (odds ratio 4.2; 95% confidence intervals 2.0-10.0), abdominal or rectal pain (4.0; 1.9-10.6), change in flatus production (2.6; 1.3-5.8), passage of mucus per rectum (2.2; 1.1-4.8). Anorexia was more common in the elderly patients (0.4; 0.1-0.8). This study suggests that symptomatic presentation of rectal cancer is different in the elderly but does not necessarily lead to greater delays in diagnosis nor higher rates of non-elective presentation.

Longitudinal study of central motor conduction time following stroke. 1. Natural history of central motor conduction.

A 12 month longitudinal study has been performed on 118 subjects following first-ever stroke to determine changes in central motor conduction time (CMCT) to upper limb muscles. The responses to electromagnetic stimulation of the motor cortex and cervical motor roots were recorded bilaterally in the surface electromyograms of pectoralis major, biceps and triceps brachii and thenar muscles. The CMCTs obtained from these recordings in stroke patients have been compared with those obtained in 53 normal healthy subjects of a similar age. The first measurements were made within the immediate post-stroke period (12-72 h of the onset of symptoms) and repeated at set time intervals over 12 months. The first assessment of CMCT identified three groups: those with normal responses, delayed responses and absent responses. During the first 12 months following stroke various changes in CMCT occurred. Central motor conduction time may remain unchanged, delayed CMCT may return to normal and previously absent responses may reappear and be delayed or normal. Using electromagnetic stimulation of the motor cortex the thresholds for motor evoked responses in the different muscles were initially high and fell over 12 months.