Freezing stress survival mechanisms in Vaccinium macrocarpon Ait. terminal buds.

Plants' mechanisms for surviving freezing stresses are essential adaptations that allow their existence in environments with extreme winter temperatures. Although it is known that Vaccinium macrocarpon Ait. buds can acclimate in fall and survive very cold temperatures during the winter, the mechanism for survival of these buds is not known. The main objective of this study was to determine which of the two major mechanisms of freezing stress survival, namely, deep supercooling or freeze-induced dehydration, are employed by V. macrocarpon terminal buds. In the present study, no low-temperature exotherms (LTEs) were detected by differential thermal analysis. Furthermore, a gradual reduction of relative liquid water content in the inner portions of buds during magnetic resonance imaging (MRI) scans performed between 0 and -20 °C (where no damage was detected in controlled freezing tests (CFT)) indicates these buds may not deep supercool. The higher ice nucleation activity of outer bud scales and the appearance of large voids in this structure in early winter, in conjunction with the MRI observations, are evidence supportive of a freeze-induced dehydration process. In addition, the presence of tissue browning in acclimated buds as a result of freezing stress was only observed in CFT at temperatures below -20 °C, and this damage gradually increased as test temperatures decreased and at different rates depending on the bud structure. Ours is the first study to collect multiple lines of evidence to suggest that V. macrocarpon terminal buds survive long periods of freezing stress by freeze-induced dehydration. Our results provide a framework for future studies of cold hardiness dynamics for V. macrocarpon and other woody perennial species and for the screening of breeding populations for freezing stress tolerance traits.

Skeletal muscle telomere length in healthy, experienced, endurance runners.

Measuring the DNA telomere length of skeletal muscle in experienced endurance runners may contribute to our understanding of the effects of chronic exposure to endurance exercise on skeletal muscle. This study compared the minimum terminal restriction fragment (TRF) length in the vastus lateralis muscle of 18 experienced endurance runners (mean age: 42 +/- 7 years) to those of 19 sedentary individuals (mean age: 39 +/- 10 years). The runners had covered almost 50,000 km in training and racing over 15 years. Minimum TRF lengths measured in the muscle of both groups were similar (P = 0.805) and within the normal range. Minimum TRF length in the runners, however, was inversely related to their years spent running (r = -0.63, P = 0.007) and hours spent training (r = -0.52, P = 0.035). Therefore, since exposure to endurance running may influence minimum TRF length, and by implication, the proliferative potential of the satellite cells, chronic endurance running may be seen as a stressor to skeletal muscle.

An investigation of the significance of Actinomycosis in tonsil disease.

OBJECTIVES: The objective of the study was to establish the incidence of Actinomycosis in the tonsils of children undergoing tonsillectomy or adenotonsillectomy, and to evaluate its role in clinical tonsillar disease. METHODS: This was a prospective controlled study done at the Red Cross Children's Hospital in Cape Town, South Africa over an 8-month period and included all children undergoing tonsillectomy or adenotonsillectomy. All resected tonsils were examined for the presence of Actinomycosis and any signs of significant cryptitis or active tonsillitis. A comparison was made in the incidence of Actinomycosis in children with obstructive sleep apnoea, recurrent tonsillitis or obstructive sleep apnoea and recurrent tonsillitis. The data was further analysed to determine the statistical significance of the association between Actinomycosis of the tonsils and age, sex and histopathological and clinical diagnosis. RESULTS: A total of 344 tonsils were analysed on 172 patients. We found 20 patients (11.6%) with Actinomycosis in the tonsils. The mean age of patients with Actinomycosis was 7.25 years and without Actinomycosis was 5.4 years (p=0.002). Most specimens (16) had no evidence of tissue reaction to Actinomyces, and their presence was found to be due to colonisation of the tonsils only. Actinomycosis was present in 11% of patients with obstructive sleep apnoea, 11% of patients with recurrent tonsillitis and in 9% with obstructive sleep apnoea and recurrent tonsillitis. The difference in incidence of Actinomycosis between these three groups (p=0.94), and between the recurrent tonsillitis group alone compared to the obstructive group (p=0.83), was not statistically significant. There was therefore no statistical significance found between Actinomyces and OSA+/- recurrent tonsillitis. CONCLUSIONS: There was no correlation found between the presence of tonsillar Actinomycosis and recurrent tonsillitis and/or obstructive tonsillar hypertrophy. Histopathologic findings showed no evidence of tissue reaction to Actinomyces and its presence was found to be due to colonisation of the tonsils only. The series did however show a statistically significant correlation between Actinomycosis colonisation and age with Actinomycosis being more common in older children, especially those over 5 years of age.

Is diagnostic tonsillectomy indicated in all children with asymmetrically enlarged tonsils?

OBJECTIVES: The aims of the study were: (i) to determine the necessity for diagnostic tonsillectomy in children with asymmetrically enlarged tonsils; (ii) to determine the accuracy of clinical assessment of tonsillar asymmetry; and (iii) to determine how to manage children with clinical tonsillar asymmetry in a developing-world practice. METHODS: A prospective study was carried out at Red Cross War Memorial Children's Hospital in Cape Town, over an 8-month period. All children undergoing tonsillectomy or adenotonsillectomy had a clinical assessment of tonsil symmetry done, and all tonsil and adenoid specimens were examined histologically. The maximum diameter and volume of the resected tonsils were measured. A comparison was done of true tonsil asymmetry in patients with asymmetrical tonsils and a subgroup of matched controls with symmetrical tonsils. RESULTS: A total of 344 tonsils were analysed (172 patients). The 13 patients (7.6%) diagnosed as having clinically asymmetrically enlarged tonsils had no significant pathological diagnosis. In the patients with symmetrical tonsils there were 2 abnormal pathological findings (tuberculosis of the adenoids and T-cell lymphoma of the tonsils and adenoids). In the clinically asymmetrical tonsil group, true tonsillar asymmetry was 3 mm (maximum diameter), and 2.2 cm(3) (volume), compared with 1.9 mm and 1.5 cm(3) in the symmetrical tonsil group. When patients with clinical tonsillar asymmetry and symmetry were compared, the difference in maximum diameter (p = 0.62) and volume (p = 0.73) was not significantly different. CONCLUSIONS: Clinical tonsillar asymmetry is usually apparent rather than real. The incidence of significant pathology in children with asymptomatic, asymmetrical tonsils is low. Diagnostic tonsillectomy is indicated in children with asymmetrically enlarged tonsils associated with constitutional symptoms, cervical lymphadenopathy, rapid tonsil enlargement or significant tonsillar asymmetry.

Intraocular rhabdomyosarcoma in the sibling of a patient with a cerebellar medulloepithelioma.

A 12-year-old girl with a three-year history of right eye disease was referred to our service after enucleation of her right eye. Histology showed a pleomorphic high-grade rhabdomyosarcoma. As there was extrascleral extension, we elected to treat her with local radiotherapy and adjuvant vincristine, dactinomycin, cyclophosphamide, and adriamycin. She remains disease free 35 months from diagnosis. Notably, a younger sibling died in early childhood as a result of a cerebellar medulloepithelioma. Although there were no teratoid elements in the rhabdomyosarcoma, our patient's unusual disease course would be consistent with rhabdomyosarcomatous differentiation in a teratoid medulloepithelioma.

Glutaraldehyde-induced bowel injury after laparoscopy.

We document the sequelae of the inadvertent introduction of glutaraldehyde into the peritoneal cavity. It describes the clinical course, progressive histological changes to the bowel at different periods over the course of 1 year, and what long-term morbidity remains. The chemical structure, effects, and pathogenesis of glutaraldehyde are described as well as suggestions for avoiding similar problems in the future.

Skeletal muscle pathology in endurance athletes with acquired training intolerance.

BACKGROUND: It is well established that prolonged, exhaustive endurance exercise is capable of inducing skeletal muscle damage and temporary impairment of muscle function. Although skeletal muscle has a remarkable capacity for repair and adaptation, this may be limited, ultimately resulting in an accumulation of chronic skeletal muscle pathology. Case studies have alluded to an association between long term, high volume endurance training and racing, acquired training intolerance, and chronic skeletal muscle pathology. OBJECTIVE: To systematically compare the skeletal muscle structural and ultrastructural status of endurance athletes with acquired training intolerance (ATI group) with asymptomatic endurance athletes matched for age and years of endurance training (CON group). METHODS: Histological and electron microscopic analyses were carried out on a biopsy sample of the vastus lateralis from 18 ATI and 17 CON endurance athletes. The presence of structural and ultrastructural disruptions was compared between the two groups of athletes. RESULTS: Significantly more athletes in the ATI group than in the CON group presented with fibre size variation (15 v 6; p = 0.006), internal nuclei (9 v 2; p = 0.03), and z disc streaming (6 v 0; p = 0.02). CONCLUSIONS: There is an association between increased skeletal muscle disruptions and acquired training intolerance in endurance athletes. Further studies are required to determine the nature of this association and the possible mechanisms involved.

Hepatoblastoma--evolution of management and outcome and significance of histology of the resected tumor. A 31-year experience with 40 cases.

BACKGROUND/PURPOSE: The aim of this study was to retrospectively evaluate and compare the clinical features, treatment strategy, pathology, and outcome of all patients with hepatoblastoma treated at an African hospital over a 31-year period (1970 to 2001). METHODS: Forty patients with hepatoblastoma were divided into 3 groups according to the treatment given. Group I (1970 to 1983, 14 patients) had no protocol therapy; group II (1984 to 1988, 6 patients) received protocol treatment according to Children's Study Group (CCSG) guidelines; group III (1989 to 2001, 20 patients) received SIOPEL protocol therapy. All available clinical, surgical, radiologic, and pathologic data were reviewed and analyzed. RESULTS: Overall patient survival was as follows: group I, 14%; group II, 50%, and group III, 80%. Deaths in group II were caused by chemotherapy-induced immunosuppression only. Prognostic data for group III showed that all tumor-related deaths could be predicted by identifying multifocal disseminated growth patterns (P =.001) or vascular invasion (P =.001) in resected tumors. Of the 40 diagnostic tumor biopsies performed, 2 significant complications (1 death, 1 intraperitoneal tumor seeding) occurred. Histologic criteria evaluating these biopsies were not predictive of overall survival. CONCLUSIONS: The introduction of protocol therapy has resulted in a marked improvement in survival. Immunosuppression-related sepsis in our setting resulted in unacceptable mortality in patients treated according to CCSG guidelines. A diagnostic biopsy in hepatoblastoma is of value but not without complications. Preoperative chemotherapy followed by complete surgical excision according to International Society of Paediatric Oncology guidelines yields excellent results with a current survival rate of 80%.

Interdigitating dendritic cell sarcoma: a report of four paediatric cases and review of the literature.

AIMS: To report a series of four paediatric cases of interdigitating dendritic cell sarcoma (IDCS) and add to the known extranodal sites of occurrence for this tumour. Neoplasms derived from interdigitating dendritic cells are rare, with only 33 cases being reported in the literature (Medline search). These tumours usually occur in lymph nodes in the adult population. METHODS AND RESULTS: The patients were a 10-year-old girl with a large soft tissue mass bulging into the left chest, a 12-year-old girl with a right paraspinal mass, a 21-month-old boy with generalized lymphadenopathy and hepatosplenomegaly and a 6-year-old girl with a large bladder mass. Paraffin blocks and haematoxylin and eosin slides were available in all cases. In addition, immunohistochemistry and electron microscopy were performed. A diagnosis of IDCS was made in all cases. CONCLUSION: The diagnosis of IDCS can rarely be entertained on clinical information alone. Microscopically, there is a wide spectrum of features. Thus, immunohistochemistry and electron microscopy are crucial in making the diagnosis. The differential diagnosis includes inflammatory pseudotumour, follicular dendritic cell sarcoma, true histiocytic lymphoma, malignant Langerhans cell histiocytosis, anaplastic large-cell lymphoma, melanoma, and a range of sarcomas. IDCS displays aggressive behaviour and approximately half of the patients die of the disease.

An enteric duplication cyst of the pancreas causing abdominal pain and pancreatitis in a child.

A rare case of a gastric duplication in the tail of the pancreas in a child presenting with recurrent abdominal pain and evidence of pancreatic calcification suggesting pancreatitis was cured by excision of the cyst and adjacent pancreas. Congenital causes of pancreatitis are rare, but are curable with surgery. These lesions are often misdiagnosed, and patients may be subjected to inappropriate surgery. Imaging is sensitive in the detection of such lesions, but the lack of specific features necessitates an index of suspicion. Similar cases have been described previously, but the pancreatic tail is rarely involved.

Improved prognosis of Epstein-Barr virus associated childhood Hodgkin's lymphoma: study of 47 South African cases.

AIM: To study the distribution of Hodgkin's lymphoma in South African children and report the incidence of Epstein-Barr virus (EBV) as regards age, race, sex, and histological subtype; to investigate whether EBV is relevant to survival. METHODS: Immunohistochemistry (IHC) and in situ hybridisation (ISH) to detect EBV were performed on 47 South African children with classical Hodgkin's lymphoma, ranging in age from 3 to 14 years and coming from different ethnic backgrounds. The correlation between the presence of the virus and clinical outcome was assessed. RESULTS: The nodular sclerosing subtype predominated, comprising 89% of cases; the remaining 11% were of the mixed cellularity subtype. EBV was present in 68%. Full clinical data were available for 36 cases; EBV positive patients presented with less aggressive symptoms at diagnosis and had a significantly longer median survival than EBV negative patients. CONCLUSIONS: The distribution of EBV in South African childhood Hodgkin's lymphoma follows a pattern intermediate to that of industrialised and non-industrialized countries. Furthermore, our data suggest that there is an association between poor prognosis and the non-detection of EBV products in South African childhood Hodgkin's lymphoma.

Computerised information systems in English mental health care providers in 1998.

BACKGROUND: This study formed part of the background work for the development work of a new Mental Health Minimum Data Set in England. It surveyed the range and nature of information systems currently used by English mental health care provider Trusts. It also surveyed relevant aspects of their organisational arrangements. METHOD: Information was collected by a telephone survey of Trust information and clinical service managers. RESULTS: Most Trusts have a complex array of different information systems--the median number is four. Even where fully integrated systems are in place, these do not necessarily cover all data areas over the whole of the Trust's operations. Sixty-three percent of Trusts use more than one patient numbering system. Sixty-percent have implemented or formally piloted routine collection of outcome scoring, 51% using the Health of the Nation Outcome Scale (HoNOS). A simple model suggested that the proposed data set could realistically be implemented nationally over a 4-year timescale. CONCLUSIONS: Given the current information system context and planned developments it would be realistic to implement the proposed Mental Health Minimum Data Set over a 4-year timescale.

Intrahepatic fetus-in-fetu: a case report and review of the literature.

The authors report the third case since 1964 of fetus-in-fetu presenting at Red Cross Children's Hospital. A fetal liver abnormality was detected during routine antenatal ultrasound scan, and the postnatal diagnosis of an intrahepatic, multiple fetus-in-fetu was made with abdominal ultrasound scan, plain radiograph of the abdomen and computed tomography. The mass was removed surgically by hemihepatectomy when the patient was 4 months of age. Imaging and the macroscopic and microscopic appearances of the abnormality confirmed the diagnosis and amplified it to include an adjacent teratoma. Multiple small subcapsular and perimass vascular hamartomas were coincidentally discovered in the liver. Two of the 3 nodules within the amniotic-lined cavity of the intrahepatic mass individually comply with the accepted criteria for fetus-in-fetu, and the third nodule has the accepted features of a benign teratoma. The existence of multiple fetus-in-fetu and fetus-in-fetu combined with a teratoma, is recorded in the medical literature. The imaging as well as the macroscopic and microscopic features are illustrated.

Sacrococcygeal germ-cell tumours--the Red Cross War Memorial Children's Hospital experience, 1980-1996.

OBJECTIVE: To document the experience of Red Cross War Memorial Children's Hospital in the treatment of sacrococcygeal germ-cell tumours. PATIENTS: Twenty-seven patients with sacrococcygeal germ-cell tumours were treated in our hospital from 1980 to 1996. DESIGN: A retrospective review of these patients' records was undertaken. RESULTS: There were 19 female and 8 male patients. Seventeen (63%) presented in the neonatal period, 13 on the first day of life. Complete surgical resection of the tumour was achieved in all patients with mature or immature teratomas (20 patients) and in 2 neonates with malignant tumours. The first of these 2 neonates, with a malignant teratoma, was not given chemotherapy and remains well 10 years later. The second, with a yolk-sac tumour, also received no initial chemotherapy. He relapsed at the age of 9 months and was successfully treated with repeat excision and chemotherapy. All 5 patients first diagnosed after the age of 1 year had malignant tumours. These patients had incomplete surgical resection (3) or biopsy only (2), and 3 were successfully treated with chemotherapy. One patient relapsed with yolksac tumour after initial complete resection of a mature teratoma. She was successfully treated with repeat surgery and chemotherapy.

The 'worn-out athlete': a clinical approach to chronic fatigue in athletes.

Chronic fatigue in the athletic population is a common but difficult diagnostic challenge for the sports physician. While a degree of fatigue may be normal for any athlete during periods of high-volume training, the clinician must be able to differentiate between this physiological fatigue and more prolonged, severe fatigue which may be due to a pathological condition. As chronic fatigue can be the presenting symptom of many curable and harmful diseases, medical conditions which cause chronic fatigue have to be excluded. The clinician must then be able to differentiate between chronic fatigue associated with training or chronic fatigue from other medical causes, and also between the chronic fatigue syndrome and the overtraining syndrome. Once the clinician has excluded all of the above medical conditions which cause chronic fatigue in athletes, a significant proportion of fatigued athletes remain without a diagnosis. Novel data indicate that skeletal muscle disorders may play a role in the development of symptoms experienced by the athlete with chronic fatigue. The histological findings from muscle biopsies of athletes suffering from the 'fatigued athlete myopathic syndrome' are presented. We have designed a clinical approach to the diagnosis and work-up of the athlete presenting with chronic fatigue. The strength of this approach is that it hinges on the participation of a multidisciplinary team in the diagnosis and management of the athlete with chronic fatigue. The athlete, coach, dietician, exercise physiologist and sport psychologist all play an important role in enabling the physician to make the correct diagnosis.

Pluripotential melanoblastoma, a unifying concept on malignancies arising in congenital melanocytic nevi: report of two cases.

Congenital melanocytic nevi are benign lesions present at birth and considered to be caused by a maldevelopment of the neural crest. The malignant potential of the congenital melanocytic nevi have been extensively addressed by several authors, and malignant melanoma is the most frequent neoplasm arising in these lesions. The present report describes two patients with congenital melanocytic nevi in which malignant melanoma with undifferentiated areas showing rhabdomyoblastic differentiation developed. The findings suggest that these mixed neoplasms may be recapitulating the differentiation potential of the ectomesenchyme-neural crest cells. We advocate the term "melanoblastoma" when referring to them.

Congenital stenotic arteriopathy with medial dysplasia of aorta, pulmonary artery, and their major branches.

This report describes the morphological findings in a young child with congenital stenotic arteriopathy who died suddenly following arteriography. Hyperplasia of all of the medial components had produced severe thickening of the wall of the aorta (mean number of lamellar units = 133 in the thoracic aorta and 125 in the abdominal aorta), the pulmonary artery, and their major proximal branches, resulting in significant luminal narrowing. Bilateral renal artery stenosis, attributable mainly to intimal longitudinal smooth muscle hyperplasia associated with fibroelastosis, was the cause of her systemic hypertension. The left ventricle showed healed subendocardial infarction.