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R Kay

Publications and source records attributed to R Kay.

At least 37 records · Page 2Linked to original sources
PubMed2001

Infections of the nervous system: an update on recent developments.

The past decade has seen major changes in the field of infectious diseases. In particular, many new infections of the nervous system have been recognised, including the lethal infections of Enterovirus 71, and the Nipah and West Nile viruses. Increased interest in prion diseases has occurred, following the recognition of animal-to-human transmission in Europe. Familiar bacteria such as the pneumococcus continue to cause problems due to increasing resistance to multiple antibiotics. Furthermore, human immunodeficiency virus-infected and other immunocompromised patients are under the constant threat of opportunistic infections, many of which are targeted towards the brain and spinal cord. This paper reviews the changing world of nervous system infections, highlighting some of the most significant recent developments.

AIDS-Associated Nephropathy↗
PubMed2001

Laparoscopic cross-trigonal Cohen ureteroneocystostomy: novel technique.

PURPOSE: We describe a novel technique of laparoscopic transvesical cross-trigonal Cohen anti-reflux ureteroneocystostomy. MATERIALS AND METHODS: A 10, an 11 and a 32-year-old patient with symptomatic unilateral vesicoureteral reflux underwent laparoscopic cross-trigonal ureteral reimplantation. Two 5 mm. balloon tip ports were suprapubically inserted into the bladder. Using a transurethral resectoscope with a Collins knife a 4 to 5 cm. cross-trigonal submucosal trough was created from the refluxing ureteral orifice to the contralateral side of the bladder. The refluxing ureteral orifice and intramural ureter were completely mobilized intravesically, advanced transtrigonally and secured to the detrusor muscle at the apex of the trough with 3 deep interrupted sutures. The elevated mucosal flaps of the trough were suture approximated over the ureter to create a submucosal tunnel. All suturing was performed by freehand laparoscopic technique. RESULTS: Operative time was between 2.5 and 4.5 hours and blood loss was 10 to 50 cc. Adequate submucosal trough creation, ureteral extravesical mobilization and intravesical advancement, and bladder mucosal flap reapproximation were done to create a submucosal tunnel in all cases. Satisfactory transtrigonal anchoring of the neoureteral orifice to the detrusor muscle and mucosa was achieved with 3 stitches. Hospital stay was 2, 2 and 1 days in the 3 cases, and the Foley catheter remained in place for 3, 1 and 1 week, respectively. At 6 months reflux had resolved in 2 patients, while in 1 grade II reflux persisted, which was improved from grade IV preoperatively. All patients have remained infection-free without antibiotics. CONCLUSIONS: Laparoscopic transvesical cross-trigonal antireflux ureteral reimplantation is technically feasible. Intravesical laparoscopic suturing is possible. Potential advantages include a decreased hospital stay, decreased narcotic requirement and better cosmesis. Further experience is necessary to refine the technical nuances and evaluate outcomes compared to the open technique.

Adult↗
PubMed2001

Variant Creutzfeldt-Jakob disease in Hong Kong.

A 34-year-old Chinese woman who had lived in the United Kingdom in the 1980s was admitted to hospital in Hong Kong because of a 7-month history of progressive neurological deterioration. Initially, she complained of heartburn and paraesthesia of the hands and feet. She then developed slowness of speech and gait, and was noted to be forgetful and irritable. In January 2001, she was brought back to Hong Kong for treatment. On admission in May she was dysarthric, ataxic, and dystonic. Magnetic resonance imaging showed high signals in both thalami suggestive of variant Creutzfeldt-Jakob disease. Other investigations, including electroencephalogram and lumbar puncture, were unremarkable. A tonsil biopsy showed the presence of prions. This patient's presentation is typical of the variant Creutzfeldt-Jakob disease cases that have been reported since 1996. Because of her residential history, we conclude that this is an imported case from the United Kingdom.

Adult↗
PubMed2000

Aspirin-associated intracerebral hemorrhage: clinical and radiologic features.

OBJECTIVE: To identify the clinical and radiologic features of intracerebral hemorrhage (ICH) in aspirin users. BACKGROUND: Although the benefits of aspirin outweigh its hemorrhagic risks for patients at high risk of vascular diseases, prolonged use of aspirin is associated with an increased risk of ICH. METHODS: The authors enrolled consecutive patients with acute stroke who were admitted to a regional hospital from 1993 to 1998 into a stroke registry. From this registry, they identified all stroke patients who had ICH confirmed by CT scan and then selected those taking regular aspirin before ICH as the study group. For each study patient, they selected the immediate next two patients with ICH but not taking aspirin as controls. RESULTS: The authors identified 58 aspirin users and 1193 nonusers among all patients hospitalized for ICH. From the group of nonusers, they selected 116 patients as controls. The locations of the hematoma were different (p = 0.002), with more lobar hematoma in the aspirin group (32.8%) than in the control group (10.3%). Prior cerebrovascular disease was the reason for taking aspirin in 37 (64%) patients but five patients had prior ICH. CONCLUSIONS: The propensity for lobar hematoma in aspirin-associated ICH suggests its pathology may be somewhat different from spontaneous ICH among nonaspirin users. Further research to examine the risks and benefits of aspirin use in certain subgroups at risk of both thrombotic and hemorrhagic events is needed.

Adult↗
PubMed2000

The alpha-synuclein gene and Parkinson disease in a Chinese population.

OBJECTIVE: To study the Ala53Thr and Ala30Pro mutations of the alpha-synuclein gene in a large number of Chinese patients with Parkinson disease (PD) as well as controls. METHODS: We recruited 183 Chinese patients with sporadic PD, 17 with younger-onset PD (onset age <50 years), and 7 with PD and a positive family history as well as 227 unaffected Chinese control subjects from the outpatient departments of 2 major hospitals in Hong Kong. All subjects were assessed for the the diagnosis of PD by a consultant neurologist or geriatrician. Subjects were interviewed with a standard questionnaire that also questioned for family history. Venous blood samples were obtained from the subjects and genomic DNA was extracted and studied for the presence of Ala53Thr mutation in exon 4 and Ala30Pro mutation in exon 3 of the alpha-synuclein gene using a polymerase chain reaction restriction fragment length polymorphism method. RESULTS: None of the Chinese PD patients or controls had either the Ala53Thr (exon 4) or Ala30Pro (exon 3) mutation of the alpha-synuclein gene. CONCLUSION: We failed to discover Ala53Thr or Ala30Pro mutations in a large number of Chinese patients with PD and control subjects, adding to the emerging consensus that variations in the alpha-synuclein gene are associated with PD in few families worldwide.

Alleles↗
PubMed2000

Transcriptional activation of tyrosinase and TRP-1 by p53 links UV irradiation to the protective tanning response.

We are exposed constantly to potentially harmful compounds and radiations. Complex adaptive protective responses have evolved to prevent such agents causing cellular damage, including potentially oncogenic mutation. The p53 tumour suppressor appears to have a role in co-ordinating such responses: it is activated by diverse insults and it acts as a transcriptional regulator of downstream genes that facilitate cellular adaptation. Ultraviolet (UV) light is a particularly potent inducer of p53 expression. In addition, UV light induces the production of melanin as a protection against further irradiation-induced damage. This study shows that the promoters of the genes coding for the enzymes crucial in melanin biosynthesis, namely tyrosinase and tyrosinase-related protein-1 (TRP-1), are activated by wild-type p53. Both promoters have p53-responsive elements and are activated in vivo in a dose-dependent manner by wild-type p53, as well as by the p53 homologues p73alpha and p63alpha.

Base Sequence↗
PubMed2000

Adrenocortical carcinoma in children. Review and recent innovations.

Adrenocortical carcinoma in childhood is a rare potentially fatal disease. Despite its often dramatic presentation, there typically has been a distressingly long delay between the onset of symptoms and the time of diagnosis. This delay undoubtedly has contributed to the historically poor prognosis in these children by permitting the disease to reach an advanced stage before treatment is started. It is imperative that the physician recognizes the endocrine manifestations of these tumors early and has a high index of suspicion. Although biochemical and histologic evaluations are helpful, they often cannot differentiate benign lesions from malignant neoplasms and should not unduly delay intervention. Aggressive complete surgical resection continues to be the mainstay of treatment and is the best prognosticator of overall survival. The role of adjuvant therapy and chemotherapy continues to evolve. Molecular studies have increased understanding of cancer biology and may provide possible novel therapeutic approaches in the future. It is hoped that increased familiarity with this unusual tumor will result in earlier detection, prompt intervention, and improved survival for children with adrenocortical carcinoma.

Adrenal Cortex Neoplasms↗
PubMed2000

Needlescopic surgery for cryptorchidism: the initial series.

PURPOSE: The aim of this study is to report the initial experience with needlescopic surgery (2-mm optics and instrumentation exclusively) for the cryptorchid testicle. METHODS: Ten patients (age 8 months to 37 years) underwent 12 needlescopic procedures: orchiopexy (n = 8), orchiectomy (n = 2), and diagnostic exploration with attempted excision of testicular remnant (n = 2). Two patients underwent bilateral needlescopic orchiopexy. Needlescopic (2 mm) optics and instrumentation were used exclusively in the pediatric patients. RESULTS: All procedures were completed successfully by needlescopic techniques. Mean surgical time was 110 minutes (range, 60 to 180 minutes), and blood loss was 6 mL (range, 0 to 20 mL). There were no intraoperative complications. All procedures were performed on an outpatient basis. In all 8 orchidopexies, the testis was successfully brought to a scrotal position. CONCLUSIONS: Needlescopic techniques allow safe performance of various procedures for a cryptorchid testicle. The cosmetic result is excellent.

Adult↗
PubMed2000

Group B streptococcal meningitis in adults: recent increase in Southeast Asia.

BACKGROUND: Meningitis caused by Streptococcus agalactiae (Group B Streptococcus) is rare in adults and usually affects patients with predisposing conditions. AIMS: To describe an increase in adult group B streptococcal meningitis occurring in parallel in Hong Kong and Singapore. METHODS: All cases of bacterial meningitis admitted to the Prince of Wales Hospital, Hong Kong and Singapore General Hospital in 1998, aged 15 years or above, were reviewed. Medical records for the previous ten years were searched for previous cases of adult group B streptococcal meningitis. RESULTS: In 1998, 29 adult patients with bacterial meningitis were admitted to the two hospitals. S. agalactiae was isolated in 11 cases, Streptococcus pneumoniae in three cases, Klebsiella pneumoniae in two cases, and Pseudomonas pseudomallei in one case. In 11 cases no bacteriological diagnosis could be made. Two patients with adult group B streptococcal meningitis had predisposing conditions for infection. One patient died before a definite diagnosis could be established. A ten year review of records revealed one previous case of adult group B streptococcal meningitis in a patient with multiple risk factors. CONCLUSIONS: An increase of group B streptococcal meningitis has occurred among adults admitted to two major hospitals in two Southeast Asian cities. In the majority of cases there were no identifiable predisposing conditions. The cause of this increase of group B streptococcal remains unclear.

Adult↗
PubMed2000

Use of transcranial Doppler ultrasound to predict outcome in patients with intracranial large-artery occlusive disease.

BACKGROUND AND PURPOSE: Intracranial large-artery occlusive disease is the predominant vascular lesion found in stroke patients of Asian, African, and Hispanic ancestry, making it numerically perhaps the most common vascular cause of stroke in the world. Relatively little is known about the clinical significance of finding such lesions. We investigate whether the presence and the extent of these vascular lesions help predict outcome after stroke. METHODS: On the basis of transcranial Doppler of the intracranial arteries with supplementary duplex ultrasound of the carotid arteries, we determined the number of occlusive arteries in the craniocervical circulation of consecutive patients who were hospitalized for acute cerebral ischemia. Patients were followed for 6 months for further vascular events (including transient ischemic attack, stroke, and acute coronary syndrome) or death. RESULTS: Among 705 consecutive Chinese patients studied, occlusive arteries were found in 345 patients (49%): 258 patients (37%) had intracranial lesions only, 71 (10%) had both extracranial and intracranial lesions, and 16 (2.3%) had extracranial lesions only. Sixty-three (18%) of the 345 patients with occlusive arteries and 35 (9.7%) of the 360 patients without occlusive arteries had further vascular event or death within 6 months. The risk of vascular events or death increased rapidly with rising numbers of occlusive arteries, after adjustment for vascular risk factors and stroke severity (adjusted odds ratio [OR] 1.25 per occlusive artery, 95% CI 1.12 to 1.39). Other independent risk factors included age (OR 1.03 per year of age, 95% CI 1.01 to 1.05) and atrial fibrillation (OR 3.00, 95% CI 1.40 to 6.69). CONCLUSIONS: In patients with predominantly intracranial large-artery occlusive disease, the presence and the total number of occlusive arteries in the craniocervical circulation predict further vascular events or death within 6 months after stroke. Transcranial Doppler ultrasound is an important investigation for the evaluation of patients with stroke in populations at risk of intracranial atherosclerotic disease.

Arterial Occlusive Diseases↗
PubMed2000

Eukaryotic signal transduction via histidine-aspartate phosphorelay.

Transmembrane signal transduction is a feature common to all eukaryotic and prokaryotic cells. We now understand that a subset of the signalling mechanisms used by eukaryotes and prokaryotes are not just similar in principle, but actually use homologous proteins. These are the histidine-aspartate phosphorelays, signalling systems of eubacterial origin, now known to be widespread in eukaryotes outside the animal kingdom. Genome projects are revealing that His-Asp phosphorelays are present as multigene families in lower eukaryotes and in plants. A major challenge is to understand how these 'novel' signal transduction systems form integrated networks with the more familiar signalling mechanisms also present in eukaryotic cells. Already, phosphorelays have been characterised that regulate MAP kinase cascades and the cAMP/PKA pathway. The probable absence of His-Asp phosphorelays from animals has generated interest in their potential as targets for anti-microbial therapy, including antifungals. Recent findings suggest that this approach holds promise.

Animals↗
PubMed2000

Penile adhesions after neonatal circumcision.

PURPOSE: The appropriate management of penile adhesions in circumcised boys is unclear. An important consideration is whether adhesions resolve spontaneously. We studied the incidence of penile adhesions as a function of patient age to assess the natural history. MATERIALS AND METHODS: We evaluated all circumcised boys presenting to our pediatric urology clinic. A standard form was used to classify adhesions as grade 0-no adhesions, 1-fine adhesions to the corona, 2-adhesions covering less than 50% of the glans and 3-adhesions covering greater than 50% of the glans. All boys were evaluated by 1 of 2 pediatric urologists. Previous treatment of adhesions was assessed and skin bridges were also noted. RESULTS: We enrolled in our study 254 boys 1 month to 19 years 8 months old. Only 7 patients had a history of treatment of adhesion, of whom 3 had recurrent adhesions at evaluation. Patients were divided into groups based on age, including younger than 12 months (61), 13 to 60 (78), 61 to 108 (51) and 109 months old or older (64). In these groups we noted an adhesion rate of 71%, 28%, 8% and 2%, respectively. The rate of adhesions more severe than grade 1 was 30%, 10% and 0% in boys 12 months old or younger, 13 to 60 and 61 months old or older, respectively. The oldest patient with grade 3 adhesions was 31 months old. Skin bridges in 6 cases involved the circumcision line in 4. CONCLUSIONS: Penile adhesions develop after circumcision and the incidence decreases with patient age. Although there is debate on whether to lyse these adhesions manually, our findings suggest that adhesions resolve without treatment. Based on our results we do not recommend lysing penile adhesions, except perhaps those involving the circumcision line.

Adolescent↗
PubMed2000

Ischaemic myelopathy presenting as Guillain-Barré syndrome.

Spinal cord stroke is uncommon. We report a woman presenting with paraesthesia followed by tetraparesis and respiratory failure who was initially diagnosed as having Guillain-Barré syndrome. Subsequent clinical and imaging features supported the diagnosis of an anterior spinal cord infarction. We describe the main clinical and imaging features of this condition.

Adult↗
PubMed2000

The practice of evidence-based medicine in an acute medical ward: retrospective study.

OBJECTIVE: To review the practice of evidence-based medicine with respect to drug treatment given to medical in-patients. DESIGN: Retrospective study. SETTING: Teaching hospital, Hong Kong. PATIENTS: Medical records of 129 consecutive patients who were admitted to the acute adult general medical ward from 1 September 1998 to 30 September 1998 were reviewed. MAIN OUTCOME MEASURES: Primary diagnoses, drug treatments prescribed, and the level of evidence (based on a literature search of randomised controlled trials and relevant studies) that supported the treatment given. RESULTS: For the 129 patients studied, 91 drug interventions had been prescribed on 312 occasions. Treatment that was supported by randomised controlled trials was prescribed in 162 (52.9%) cases. In 121 (38.8%) cases, patients were given standard and commonly used drugs that were not supported by evidence from clinical trials, and in 29 (9.3%) cases, the treatments given had no substantial supporting evidence. The management of some frequently encountered medical conditions was not based on trial data, because the relevant studies had not been conducted. CONCLUSION: Basing treatment on comparative efficacy results is a worthwhile goal, but there are limitations in conducting literature searches to identify relevant trials and studies. Evidence-based medical practice is not applicable in a large number of commonly encountered conditions.

Adult↗
PubMed1999

Pediatric urinary tract infection and reflux.

Urinary tract infections in children are sometimes associated with vesicoureteral reflux, which can lead to renal scarring if it remains unrecognized. Since the risk of renal scarring is greatest in infants, any child who presents with a urinary tract infection prior to toilet training should be evaluated for the presence of reflux. Children who may be lost to follow-up and those who have recurrent urinary tract infections should also be evaluated. The preferred method for evaluation of urinary reflux is a voiding cystourethrogram. Documented reflux is initially treated with prophylactic antibiotics. Patients who have breakthrough infections on prophylaxis, develop new renal scarring, have high-grade reflux or cannot comply with long-term antibiotic prophylaxis should be considered for surgical correction. The preferred method of surgery is ureteral reimplantation. A newer method involves injection of the bladder trigone with collagen.

Child↗