Cardiovascular response to exercise training in the systemic right ventricle of adults with transposition of the great arteries

KEY POINTS

Patients with transposition of the great arteries (TGA) and systemic right ventricles have premature congestive heart failure; there is also a growing concern that athletes who perform extraordinary endurance exercise may injure the right ventricle. Therefore we felt it essential to determine whether exercise training might injure a systemic right ventricle which is loaded with every heartbeat. Previous studies have shown that short term exercise training is feasible in TGA patients, but its effect on ventricular function is unclear. We demonstrate that systemic right ventricular function is preserved (and may be improved) in TGA patients with exercise training programmes that are typical of recreational and sports participation, with no evidence of injury on biomarker assessment. Stroke volume reserve during exercise correlates with exercise training response in our TGA patients, identifying this as a marker of a systemic right ventricle (SRV) that may most tolerate (and possibly even be improved by) exercise training.

ABSTRACT

We aimed to assess the haemodynamic effects of exercise training in transposition of the great arteries (TGA) patients with systemic right ventricles (SRVs). TGA patients have limited exercise tolerance and early mortality due to systemic (right) ventricular failure. Whether exercise training enhances or injures the SRV is unclear. Fourteen asymptomatic patients (34 ± 10 years) with TGA and SRV were enrolled in a 12 week exercise training programme (moderate and high-intensity workouts). Controls were matched on age, gender, BMI and physical activity. Exercise testing pre- and post- training included: (a) submaximal and peak; (b) prolonged (60 min) submaximal endurance and (c) high-intensity intervals. Oxygen uptake (V̇O2; Douglas bag technique), cardiac output (Q̇c, foreign-gas rebreathing), ventricular function (echocardiography and cardiac MRI) and serum biomarkers were assessed. TGA patients had lower peak V̇O2, Q̇c, and stroke volume (SV), a blunted Q̇c/V̇O2 slope, and diminished SV response to exercise (SV increase from rest: TGA = 15.2%, controls = 68.9%, P < 0.001) compared with controls. After training, TGA patients increased peak V̇O2 by 6 ± 8.5%, similar to controls (interaction P = 0.24). The magnitude of SV reserve on initial testing correlated with Q̇c training response (r = 0.58, P = 0.047), though overall, no change in peak Q̇c was observed. High-sensitivity troponin T (hs-TnT) and N-terminal prohormone of brain naturetic peptide (NT pro-BNP) were low and did not change with acute exercise or after training. Our data show that TGA patients with SRVs in this study safely participated in exercise training and improved peak V̇O2. Neither prolonged submaximal exercise, nor high-intensity intervals, nor short-term exercise training seem to injure the systemic right ventricle.

Adding heat to the live-high train-low altitude model: a practical insight from professional football

Objectives

To examine with a parallel group study design the performance and physiological responses to a 14-day off-season ‘live high-train low in the heat’ training camp in elite football players.

Methods

Seventeen professional Australian Rules Football players participated in outdoor football-specific skills (32±1°C, 11.5 h) and indoor strength (23±1°C, 9.3 h) sessions and slept (12 nights) and cycled indoors (4.3 h) in either normal air (NORM, n=8) or normobaric hypoxia (14±1 h/day, FiO₂ 15.2–14.3%, corresponding to a simulated altitude of 2500–3000 m, hypoxic (HYP), n=9). They completed the Yo-Yo Intermittent Recovery level 2 (Yo-YoIR2) in temperate conditions (23±1°C, normal air) precamp (Pre) and postcamp (Post). Plasma volume (PV) and haemoglobin mass (Hb_mass) were measured at similar times and 4 weeks postcamp (4WPost). Sweat sodium concentration ((Na⁺)_sweat) was measured Pre and Post during a heat-response test (44°C).

Results

Both groups showed very large improvements in Yo-YoIR2 at Post (+44%; 90% CL 38, 50), with no between-group differences in the changes (−1%; −9, 9). Postcamp, large changes in PV (+5.6%; −1.8, 5.6) and (Na⁺)_sweat (−29%; −37, −19) were observed in both groups, while Hb_mass only moderately increased in HYP (+2.6%; 0.5, 4.5). At 4WPost, there was a likely slightly greater increase in Hb_mass (+4.6%; 0.0, 9.3) and PV (+6%; −5, 18, unclear) in HYP than in NORM.

Conclusions

The combination of heat and hypoxic exposure during sleep/training might offer a promising ‘conditioning cocktail’ in team sports.

Fungicide Sensitivity of Pythium spp. Associated with Cavity Spot of Carrot in California and Michigan

The identity of 172 isolates of Pythium spp. from cavity spot lesions on carrot produced in California and Michigan was determined, and their sensitivity to three fungicides was examined. Pythium violae accounted for 85% of California isolates, with P. irregulare, P. dissotocum (the first report as a carrot pathogen in the United States), P. ultimum, and P. sulcatum making the balance. P. sulcatum, P. sylvaticum, and P. intermedium were the most commonly recovered (85%) species in Michigan; others from Michigan included P. intermedium, P. irregulare, and an unclassified strain, M2-05. On fungicide-amended media, 93% of isolates were sensitive to mefenoxam (inhibition of mycelial growth was >60% at 10 μg active ingredient [a.i.]/ml); however, two of five isolates of P. irregulare from California were highly resistant (≤60% inhibition at 100 μg a.i./ml); about half of the isolates of P. intermedium and P. sylvaticum and a single isolate of P. violae were highly or intermediately resistant to mefenoxam (>60% inhibition at 100 μg a.i./ml, or ≤60% inhibition at 10 μg a.i./ml). P. dissotocum, P. irregulare, P. sulcatum, M2-05, and three of seven isolates of P. intermedium were insensitive to fluopicolide (effective concentrations for 50% growth inhibition [EC₅₀] were >50 μg a.i./ml), while P. sylvaticum, P. ultimum, P. violae, and some isolates in P. intermedium were sensitive (EC₅₀ < 1 μg a.i./ml). All isolates were sensitive to zoxamide (EC₅₀ < 1 μg a.i./ml). Sensitivity baselines of P. violae to zoxamide and fluopicolide were established.

Surface motility of Xylella fastidiosa visualized by oblique illumination

Stereomicroscopic observations using oblique illuminations revealed the presence of two types of movement trails by Xylella fastidiosa strains (A- and G-genotypes) isolated from almond-leaf scorch samples on the surface of PW and PD3 culture media. The A-genotype strains showed curved motility trails, and the G-genotype strains showed straight motility trails. Haloes were found around some G-genotype colonies due to the excretion of unknown factors and (or) compounds, which might be related to bacterial surface motility.

Diagnostic accuracy of a fibrosis serum panel (FIBROSpect II) compared with Knodell and Ishak liver biopsy scores in chronic hepatitis C patients

Liver biopsy is the primary method of assessing liver injury in hepatitis C patients. FIBROSpect II (FS), a diagnostic panel of three extracellular matrix remodelling markers, may be useful as a noninvasive alternative to this procedure. The purpose of this study was to correlate FS results with liver fibrosis scores to determine if this test is sufficiently accurate to be a viable alternative to liver biopsy. A total of 142 serum specimens were evaluated for fibrosis with FS and were compared with Knodell and Ishak fibrosis scores. FS reports an index score ranging from 0.1 to 1.0, which corresponds to the probability of progressive liver fibrosis. Using a FS index cut-off of 0.42, 50 of 54 patients with Ishak 3-6 were classified as having advanced fibrosis (METAVIR F2-F4) and 58 of 88 patients with Ishak 0-2 as having no/mild fibrosis (METAVIR F0-F1), resulting in a sensitivity of 93%, specificity of 66%, and an overall test accuracy of 76%. With a 38% prevalence of advanced fibrosis, the negative predictive value was 94% and positive predictive value was 63%. A biopsy length of > or = 2 cm was associated with higher concordance between FS results and liver fibrosis scores (P = 0.01). FS was clinically useful in ruling out advanced fibrosis in hepatitis C by identifying patients with mild disease in whom treatment could be deferred. The limitation of this test is its decreased sensitivity and specificity in the middle of the test's reporting range between scores of 0.42 and 0.80.

First Report of Puccinia sorghi on Maize in Oman

Maize (Zea mays L.) is an important annual forage crop cultivated in the Sultanate of Oman, especially during the summer months. It is used for green fodder and grains and often intercropped in fruit orchards, especially under date palms. In April of 2005, leaf samples showing rust symptoms were collected from Samail, 100 km south of Muscat. Oval-shaped, red-brown pustules covered both sides of the leaves and yielded urediniospores typical of Puccinia sorghi Schwein. Urediniospores were roughly subglobose, measured 23 to 28 × 20 to 25 μm, echinulate, with three or four equitorial germ pores (2). Teliospores (38 to 42 × 16 to 19 μm) were observed, but few in numbers, most probably because of the time of year of collection. Pathogen identity was confirmed by nuclear ribosomal large subunit (28S) and internal transcribed spacer region 2 (ITS-2) DNA analysis (voucher sequence deposited in GenBank, Accession No. DQ345724, voucher specimen deposited in the U.S. National Fungus Collections, BPI 871134). P. sorghi has previously been reported from Yemen and Saudi Arabia (1) but not from Oman. Maize is grown throughout the year in Oman, and pathogen survival probably does not require the presence of the alternate host, nonetheless, Oxalis species are present and current research is attempting to locate and confirm the presence of the aecial stage in Oman. References: (1) CMI Distribution Maps of Plant Diseases. Map No. 279. Ed. 4. CABI, Wallingford, UK, 1978. (2) D. G. White, ed. Compendium of Corn Diseases. The American Phytopathological Society, St Paul, MN, 1999.

First Report of 16S rDNA II Group Phytoplasma on Polygala mascatense, a Weed in Oman

Polygala mascatense Boiss. (family Polygalaceae) is a common weed found in neglected farms, under date palm trees, and in stony locations throughout the Sultanate of Oman (1). It is a perennial herb approximately 30 to 40 cm tall, has slender branches, is woody at the base, and has linear leaves with purple flowers. Recently (November 2004), in the interior region of Oman (210 km south of Muscat), some polygala plants were found stunted with small leaves, bushy growth, and the floral parts were showing phyllody symptoms. Total genomic DNA extracted from asymptomatic and symptomatic plants with modified cetyltrimethylammoniumbromide (CTAB) buffer method (4) was used as a template for direct polymerase chain reaction (PCR) amplification of phytoplasma 16S rDNA with P1/P7 primers. Direct PCR product was used as template DNA for nested PCR with primers R16F2n/R16R2. DNA from plants infected with alfalfa and lime witches'-broom phytoplasma was used as positive controls, and DNA from healthy plants and water was used as negative controls. Products from nested PCR (1.2 kb) were analyzed by using single endonuclease enzyme digestion (restriction fragment length polymorphism [RFLP]) with Tru9I, HaeIII, HhaI, TaqI, AluI, and RsaI (3). The results showed the presence of a 1.8-kb product amplified with direct PCR and a 1.2-kb product of the nested PCR from infected polygala and the positive controls, whereas no PCR products were observed in the negative controls. The PCR assay confirmed the presence of phytoplasma causing witches'-broom disease in polygala. The RFLP results showed the polygala phyto-plasma to be most similar to the alfalfa phytoplasma, a member of 16SrII group (2). Infected polygala weeds may serve as a reservoir for alfalfa witches'-broom phytoplasma that causes annual losses over $25 million to alfalfa cultivation in Oman (2). A detailed investigation needs to be carried out to establish transmission of phytoplasma from polygala to alfalfa. To our knowledge, this is the first report of phytoplasma infecting polygala weeds in Oman. References: (1) S. A. Ghazanfar. Pages 95-96 in: An Annotated Catalogue of the Vascular Plants in Oman. Scripta Botanica Belgica Meise, National Botanic Garden of Belgium, 1992. (2) A. J. Khan et al. Phytopathology 92:1038, 2002. (3) I. M. Lee et al. Int. J. Syst. Bacteriol. 1153, 1998. (4) M. A. Saghai-Maroof et al. Proc. Natl. Acad. Sci. USA 81:8014, 1984.

Intestinal complications after chemotherapy for patients with unresected primary colorectal cancer and synchronous metastases

BACKGROUND

The role of palliative resection of the primary tumour in patients who present with metastatic colorectal cancer is unclear.

AIMS

This study compared the incidence of major intestinal complications in such patients who received chemotherapy treatment with or without prior palliative resection of the primary tumour.

PATIENTS

The incidence of intestinal obstruction, perforation, fistula formation, and gastrointestinal haemorrhage, and the requirement for abdominal radiotherapy in patients with metastatic colorectal cancer treated at a single institution over a 10 year period was determined.

RESULTS

Eighty two patients received initial treatment with chemotherapy without resection of the primary tumour (unresected group) and 280 patients had undergone prior resection (resected group). In the unresected group, the incidence of peritonitis, fistula formation, and intestinal haemorrhage was 2.4% (95% confidence interval (CI) 0.3-8.5%), 3.7% (95% CI 0.8-10.3%), and 3.7% (95% CI 0.8-10.3%), respectively, and was not significantly different from the resected group. Intestinal obstruction affected 13.4% (95% CI 6.9-22.7%) of patients in the unresected group and 13.2% (95% CI 9.2-17.2%) of patients in the resected group. More patients in the unresected group required >/=3 blood transfusions (14.6% v 7.5%; p=0.048) and abdominal radiotherapy (18.3% v 9.6%; p=0.03) than the resected group.

CONCLUSIONS

The incidence of major intestinal complications in patients with unresected colorectal cancer and synchronous metastases who receive initial treatment with chemotherapy is low. Chemotherapy may be successfully used as initial treatment for such patients with no increased risk of most major intestinal complications compared with patients who have undergone initial resection of the primary tumour.

Loss of MHC class II inducibility in hyperplastic tissue in Rb-defective mice

Retinoblastoma gene (Rb) defects occur frequently in human tumors. Studies of Rb-defective human tumor cell lines and Rb-/- murine embryonic fibroblasts demonstrate that Rb is required for interferon-gamma (IFN-gamma) induced major histocompatibility complex (MHC) class II expression. MHC class II expressing tumors generate anti-tumor immune responses associated with tumor-specific infiltrating lymphocytes. The role of Rb in IFN-gamma induced MHC class II expression on an endogenous tumor was examined by immunohistochemical staining for IAbeta and Rb on tissues from Rb+/- mice. MHC class II IAbeta is not induced by IFN-gamma in Rb-deficient neoplastic cells, but remains inducible in related normal tissue.

Defective transforming growth factor beta signaling pathway in head and neck squamous cell carcinoma as evidenced by the lack of expression of activated Smad2

PURPOSE

Transforming growth factor beta (TGF-beta) regulates cell growth and differentiation, in normal squamous epithelium, via specific TGF-beta receptors and intracellular signaling molecules (Smads). We have previously observed that TGF-beta type II receptor (TbetaR-II) expression decreases in squamous cell carcinomas as tumors become less differentiated and more biologically aggressive. However, a small fraction of tumors remain TbetaR-II positive. In this article, we examine the integrity of the other members of the TGF-beta-signaling machinery, the Smad proteins.

EXPERIMENTAL DESIGN

Thirteen archived head and neck squamous cell carcinomas were selected from the files of the Pathology Department of the H. Lee Moffitt Cancer Center. Protein immunoexpression was quantitated by image analysis in the context of histopathological parameters. Mutation analysis of the MADR2/Smad2 gene was also performed.

RESULTS

In both TbetaR-II-positive and TbetaR-II-negative tumors, expression of the non-TGF-beta-specific Smads (4, 6, and 7) was variable, whereas expression of the pathway-specific Smad2 was lost in 38% of the tumors. Expression of the activated, phosphorylated form of this molecule, Smad2-P, was lost in approximately 70% of the tumors. No abnormal mRNA expression and no mutations in the MADR2/Smad2 gene were observed.

CONCLUSIONS

These results suggest that multiple defects in TGF-beta signaling, both at the receptor and postreceptor level, may play a role in the oncogenesis of head and neck squamous cell carcinoma.

A SNP resource for human chromosome 22: extracting dense clusters of SNPs from the genomic sequence

The recent publication of the complete sequence of human chromosome 22 provides a platform from which to investigate genomic sequence variation. We report the identification and characterization of 12,267 potential variants (SNPs and other small insertions/deletions) of human chromosome 22, discovered in the overlaps of 460 clones used for the chromosome sequencing. We found, on average, 1 potential variant every 1.07 kb and approximately 18% of the potential variants involve insertions/deletions. The SNPs have been positioned both relative to each other, and to genes, predicted genes, repeat sequences, other genetic markers, and the 2730 SNPs previously identified on the chromosome. A subset of the SNPs were verified experimentally using either PCR-RFLP or genomic Invader assays. These experiments confirmed 92% of the potential variants in a panel of 92 individuals. [Details of the SNPs and RFLP assays can be found at http://www.sanger.ac.uk and in dbSNP.]

Testing a model of the influence of family problem factors on high-risk youths' troubled behavior: a three-wave longitudinal study

Using data collected in a study of arrested youths processed at a juvenile assessment center who entered a home-based family intervention project, the authors test a three-stage longitudinal model. The model reflects a developmental damage view of the relationships of the youths' family problems (including their physical abuse and sexual victimization experiences) to their drug use and delinquent behavior over time. The hypothesized model is supported by the data. Research, theoretical, and policy implications of the results are drawn.

Transforming growth factor beta receptors in verrucous and squamous cell carcinoma

OBJECTIVES

To study the intracellular location of transforming growth factor beta type II receptors (TbetaR-II) in verrucous carcinoma (VC) and squamous cell carcinoma (SqCC), and to evaluate their role in the biological behavior of both neoplasias.

DESIGN

Ten VC and 10 well-differentiated SqCC specimens were analyzed by immunohistochemistry and in situ hybridization for the expression and intracellular location of TbetaR-II. Receptor expression was evaluated in areas of invasion and in areas of transformation of VC into SqCC. TbetaR-II expression was compared with expression of the type I receptor (TbetaR-I).

SUBJECTS

Formalin-fixed, paraffin-embedded tissue sections from VCs and well-differentiated SqCCs, operated on at the H. L. Moffitt Cancer Center and Research Institute from May 1987 to January 1998, were selected for the study.

INTERVENTIONS

None.

RESULTS

While in all VCs TbetaR-II was found to be located along the membrane of the neoplastic keratinocytes, TbetaR-II expression in SqCC was observed predominantly in a cytoplasmic location. This cytoplasmic location of TbetaR-II was also seen in areas of transition from VC to SqCC. Expression of TbetaR-I was found in a cytoplasmic location in both tumor types.

CONCLUSIONS

The membranous location of TbetaR-II in VC exposes the receptor to the growth inhibitory control of TGF-beta and may explain why VC tumors are less aggressive clinically. The marked reduction of membranous TbetaR-II and their predominant cytoplasmic location diminishes TGF-beta growth inhibition and may contribute to the transformation of VC into the more aggressive SqCC.

Cyclin D1 expression as a prognostic parameter in papillary carcinoma of the thyroid

Papillary carcinoma of the thyroid is the most common thyroid cancer. At the time of clinical presentation, most papillary carcinomas are still confined to the thyroid gland, and appropriate surgical treatment achieves a 95% 5-year survival rate. Certain carcinomas, however, behave in a much more aggressive fashion. Because specific therapies do not exist, for those tumors that have escaped local control, patients with disseminated disease have little or no chance of permanent cure or long-term survival. Cyclin D1, a protein that plays a critical role in the control of the cell cycle, has been shown to be overexpressed in a variety of human neoplasias and may serve as a prognostic parameter of disease progression. To explore the role played by cyclin D1 in the pathogenesis of thyroid papillary carcinoma, we have quantitated, by computerized image analysis, the immunohistochemical expression of cyclin D1 in formalin-fixed, paraffin-embedded tissue from 35 conventional papillary carcinomas of the thyroid and correlated the results with established clinicopathologic parameters and available survival data.

Transforming growth factor beta receptors and p27kip in thyroid carcinoma

OBJECTIVE

To investigate the role of cell cycle regulators in the pathogenesis of papillary carcinoma of the thyroid.

DESIGN

Resistance to transforming growth factor beta-mediated inhibition is a well-known pathogenic mechanism in epithelial neoplasias. In a retrospective study, the expression of transforming growth factor beta receptors types I and II, cyclin D1, and the cyclin-dependent inhibitor p27kip, was analyzed by immunohistochemistry. Results were interpreted in the context of clinicopathological data. Patient follow-up ranged from 1 to 18 years, with a mean of 4 years.

MATERIALS

Twenty conventional primary papillary carcinomas and their metastases were selected according to current pathologic criteria. Nonconventional papillary carcinomas (eg, tall-cell, columnar) were excluded from the analysis.

RESULTS

Cyclin D1 was expressed more intensely in the tumor than in adjacent nonneoplastic parenchyma. Within a given tumor, however, there was significant heterogeneity in expression intensity and percentage of positive cells, particularly in metastases. Type I receptors were strongly expressed in 90% of tumors, while 80% of the tumors revealed low to no expression of type II receptors. In 10% of tumors, type I receptors were absent and type II receptors expressed. Simultaneous absence of both receptors was not observed. While p27kip was strongly expressed in nonneoplastic thyroid, it was not detected in any of the primary tumors or their metastases.

CONCLUSIONS

The results strongly suggest that functional abnormalities in type II receptors result in increased levels of cyclin D1 and down-regulation of p27kip. This would maintain cells in a proliferative state and would promote tumor progression.

Argyrophilic nucleolar organizer regions in breast carcinoma. Correlation with DNA flow cytometry, histopathology, and lymph node status

Argyrophilic nucleolar organizer regions (AgNOR) have been correlated with proliferative activity of neoplasms. Increased AgNOR may reflect increased proliferative activity of cells or ploidy. To explore this hypothesis, 41 breast carcinomas were processed for AgNOR silver staining and DNA flow cytometry. AgNOR counts were expressed as mean AgNOR/nucleus and percentage of tumor cells with more than five AgNOR/nucleus. The first count was designated mean AgNOR or mAgNOR, and the second count was designated AgNOR proliferative index or pAgNOR. Using Mantel-Haensel statistical analysis, carcinomas that exhibited mAgNOR of 2.4 or more had a high likelihood of aneuploidy (P less than 0.0001), an S-phase fraction of more than 5.8% (P less than 0.003), or a diameter greater than 2 cm (P less than 0.007). In addition, tumors with pAgNOR of 8% or more showed a statistically significant correlation with aneuploidy (P less than 0.004), tumor grade (P less than 0.04), and a more significant one with high S-phase fraction (P less than 0.0001). No significant correlation was obtained between pAgNOR and tumor size or lymph node status. These data indicate that AgNOR quantitation reflects changes in DNA ploidy and cell proliferation. They also suggest that the mean AgNOR counts correlate best with the DNA mass or ploidy and that the frequency of cells with higher AgNOR count best reflects proliferative activity or S-phase fraction.

Marketing to the Hispanic-American community

In these financially constrained times, should your company spend money developing ways to sell your prod‐ucts or services to Hispanics? Unless you can afford to overlook a booming $171‐billion market, the answer is a resounding yes. The Hispanic market will be even more significant in the coming years; Hispanics are the US's number‐one growth market due to high birth and immigration rates.

The immediate postoperative prosthesis (IPOP) in ischemia and septic amputations

A retrospective analysis of the medical records of 17 consecutive patients undergoing lower extremity amputation and Immediate Postoperative Prosthesis (IPOP) placement for infectious complications of unreconstructable arterial insufficiency was performed. Significant soft tissue infection was present in 13 patients and osteomyelitis in four. The mean patient age was 59.4 years and 13 of 17 patients were diabetic. Fourteen patients underwent below knee and three underwent above knee amputations. Seven patients had undergone previous arterial reconstruction. Thirteen patients had previous ipsilateral amputations, five of which were open guillotine amputations performed between 3 and 7 days prior to definitive surgery. Four individuals (24%) required early removal of the IPOP, two due to patient noncompliance and two due to stump healing complications. Thirteen patients (76%) were successfully treated with IPOP and went on to achieve independent gait within 3 weeks of their definitive amputation.

Paraventricular--suprachiasmatic lesions prevent salt-induced hypertension in Dahl rats

1. We studied the effects that lesions produced in the paraventricular and suprachiasmatic nuclei and intervening periventricular area had on 24 h mean circadian blood pressures in Dahl salt-sensitive and -resistant rats and their sham-operated controls. We measured blood pressures while the animals were on a low salt diet and after 1, 5 and 13 weeks of 8% NaCl diet. 2. Salt-sensitive rats with lesions had lower blood pressures than salt-sensitive sham-operated controls at all points of the study. In contrast, identical lesions in salt-resistant rats produced a transient pressor response to the diet. Twenty-four hour mean heart rate, determined after 13 weeks of 8% NaCl intake, was low only in salt-sensitive rats with lesions. Sodium intake and excretion per kg of body weight, as well as plasma sodium concentrations, were similar in all groups. 3. We conclude that the anteromedial hypothalamic area, which includes the paraventricular nucleus, the suprachiasmatic nucleus and the intervening periventricular area, participates in the development of Dahl hypertension. We suggest that a multifactorial mechanism is involved: (a) the facilitatory role of this region in ACTH release, (b) this region's participation in the baroreceptor reflex via vasopressinergic efferents to the nucleus of the tractus solitarius, and (c) the roles of the paraventricular and suprachiasmatic nuclei in the regulation of salt and water balance.

Phenobarbital vs. phenytoin for grand mal epilepsy

The chief side effect of phenobarbital is drowsiness, which is usually associated with overdosage. Phenytoin, on the other hand, causes gingival hyperplasia in many patients, irreversible hypertrichosis in some patients and lethal reactions, such as Stevens-Johnson syndrome, in a few patients. Antiepileptic therapy should always be started with one drug. Phenytoin is specifically contraindicated as the drug of first choice for infants, females (especially adolescents) and children receiving orthodontic treatment.

Petit mal epilepsy

Petit mal epilepsy is primarily a disorder of childhood. It is a comparatively rare type of seizure and is relatively benign. It rarely causes demonstrable evidence of pathologic cerebral changes, except in patients who have frequent attacks of petit mal status. Patients with petit mal epilepsy are prone to develop major motor (grand mal) seizures. Therefore, concurrent administration of petit mal and major motor anticonvulsants is recommended.