Coherent spin qubit transport in silicon

A fault-tolerant quantum processor may be configured using stationary qubits interacting only with their nearest neighbours, but at the cost of significant overheads in physical qubits per logical qubit. Such overheads could be reduced by coherently transporting qubits across the chip, allowing connectivity beyond immediate neighbours. Here we demonstrate high-fidelity coherent transport of an electron spin qubit between quantum dots in isotopically-enriched silicon. We observe qubit precession in the inter-site tunnelling regime and assess the impact of qubit transport using Ramsey interferometry and quantum state tomography techniques. We report a polarization transfer fidelity of 99.97% and an average coherent transfer fidelity of 99.4%. Our results provide key elements for high-fidelity, on-chip quantum information distribution, as long envisaged, reinforcing the scaling prospects of silicon-based spin qubits.

Wiskott Aldrich Syndrome: A Multi-Institutional Experience From India

Background

Wiskott Aldrich syndrome (WAS) is characterized by bleeding manifestations, recurrent infections, eczema, autoimmunity, and malignancy. Over the last decade, improved awareness and better in-house diagnostic facilities at several centers in India has resulted in increased recognition of WAS. This study reports collated data across major primary immunodeficiency diseases (PID) centers in India that are involved in care of children with WAS and highlights the varied clinical presentations, genetic profile, and outcomes of patients in India.

Methods

Request to share data was sent to multiple centers in India that are involved in care and management of patients with PID. Six centers provided requisite data that were compiled and analyzed.

Results

In this multi-institutional cohort, clinical details of 108 patients who had a provisional diagnosis of WAS were received. Of these, 95 patients with 'definite WAS' were included Fourteen patients were classified as XLT and 81 patients as WAS. Median age at onset of symptoms of patients was 3 months (IQR 1.6, 6.0 months) and median age at diagnosis was 12 months (IQR 6,48 months). Clinical profile included bleeding episodes (92.6%), infections (84.2%), eczema (78.9%), various autoimmune manifestations (40%), and malignancy (2.1%). DNA analysis revealed 47 variants in 67 cases. Nonsense and missense variants were the most common (28.4% each), followed by small deletions (19.4%), and splice site defects (16.4%). We also report 24 novel variants, most of these being frameshift and nonsense mutations resulting in premature termination of protein synthesis. Prophylactic intravenous immunoglobulin (IVIg) was initiated in 52 patients (54.7%). Hematopoietic stem cell transplantation (HSCT) was carried out in 25 patients (26.3%). Of those transplanted, disease-free survival was seen in 15 patients (60%). Transplant related mortality was 36%. Outcome details were available for 89 patients. Of these, 37% had died till the time of this analysis. Median duration of follow-up was 36 months (range 2 weeks- 12 years; IQR 16.2 months- 70 months).

Conclusions

We report the first nationwide cohort of patients with WAS from India. Bleeding episodes and infections are common manifestations. Mortality continues to be high as curative therapy is not accessible to most of our patients.

A clinical prediction score using age at diagnosis and saline infusion test parameters can predict aldosterone-producing adenoma from idiopathic adrenal hyperplasia

PURPOSE

Accurate subtyping of the primary aldosteronism into aldosterone-producing adenoma (APA) and idiopathic adrenal hyperplasia (IAH) is important to direct for specific treatment modalities. The objective of the study was to compare the clinical and biochemical parameters of APA and IAH patients to derive a Clinical Prediction Score reliably predicting APA from IAH.

METHODS

This was a retrospective multi-centre study recruiting 38 APA patients and 42 IAH patients from four major hospitals in Hong Kong using database from Surgical Outcomes Monitoring and Improvement Programme and Clinical Data Analysis and Reporting System. Their clinical and biochemical parameters were evaluated.

RESULTS

Patients in APA group were younger than IAH group (mean age 48.6 ± 9.2 vs. 57.1 ± 7.3 years old, p < 0.001), had more suppressed renin before saline infusion in saline infusion test (SIT) (median 0.19 [IQR 0.15-0.37] vs. 0.39 [IQR 0.19-0.69] ng/mL/h, p = 0.01), and higher aldosterone level after saline infusion in SIT (median 674 [IQR 498-1000] vs. 327 [IQR 242-483] pmol/L, p < 0.001). A clinical prediction score using three parameters was devised, comprising age at diagnosis < 50 years, PRA before saline infusion in SIT ≤ 0.26 ng/mL/h, and aldosterone level after saline infusion in SIT ≥ 424 pmol/L. A score of 2 would predict APA with a sensitivity of 84.2% and specificity of 88.1%, and a score of 3 would predict APA with a sensitivity of 31.6% and specificity of 100%.

CONCLUSIONS

Clinical Prediction Score based on the combination of age at diagnosis, PRA, and aldosterone level in the saline infusion tests could reliably predict APA from IAH.

Coherent spin control of s-, p-, d- and f-electrons in a silicon quantum dot

Once the periodic properties of elements were unveiled, chemical behaviour could be understood in terms of the valence of atoms. Ideally, this rationale would extend to quantum dots, and quantum computation could be performed by merely controlling the outer-shell electrons of dot-based qubits. Imperfections in semiconductor materials disrupt this analogy, so real devices seldom display a systematic many-electron arrangement. We demonstrate here an electrostatically confined quantum dot that reveals a well defined shell structure. We observe four shells (31 electrons) with multiplicities given by spin and valley degrees of freedom. Various fillings containing a single valence electron-namely 1, 5, 13 and 25 electrons-are found to be potential qubits. An integrated micromagnet allows us to perform electrically-driven spin resonance (EDSR), leading to faster Rabi rotations and higher fidelity single qubit gates at higher shell states. We investigate the impact of orbital excitations on single qubits as a function of the dot deformation and exploit it for faster qubit control.

Single-spin qubits in isotopically enriched silicon at low magnetic field

Single-electron spin qubits employ magnetic fields on the order of 1 Tesla or above to enable quantum state readout via spin-dependent-tunnelling. This requires demanding microwave engineering for coherent spin resonance control, which limits the prospects for large scale multi-qubit systems. Alternatively, singlet-triplet readout enables high-fidelity spin-state measurements in much lower magnetic fields, without the need for reservoirs. Here, we demonstrate low-field operation of metal-oxide-silicon quantum dot qubits by combining coherent single-spin control with high-fidelity, single-shot, Pauli-spin-blockade-based ST readout. We discover that the qubits decohere faster at low magnetic fields with [Formula: see text] μs and [Formula: see text] μs at 150 mT. Their coherence is limited by spin flips of residual 29Si nuclei in the isotopically enriched 28Si host material, which occur more frequently at lower fields. Our finding indicates that new trade-offs will be required to ensure the frequency stabilization of spin qubits, and highlights the importance of isotopic enrichment of device substrates for the realization of a scalable silicon-based quantum processor.

Cost-utility analysis of 21-gene assay for node-positive early breast cancer

Background

For women with lymph node (ln)-positive, estrogen receptor-positive, and her2 (human epidermal growth factor receptor 2)-negative breast cancer (bca), current guidelines recommend treatment with both hormonal therapy and chemotherapy. The 21-gene Recurrence Score (rs) assay might be helpful in selecting patients with bca who can be spared chemotherapy when they have 1-3 positive lns and a lower risk of recurrence. In the present study, we performed a cost-utility analysis comparing use of the 21-gene rs assay with current practice from the perspective of a Canadian health care payer.

Methods

A Markov model was developed to determine costs and quality-adjusted life-years (qalys) over a patient's lifetime. Patient outcomes in both study groups were examined based on published clinical trials. Costs were derived primarily from published Canadian sources. Costs and outcomes were discounted at 1.5% annually, and costs are reported in 2016 Canadian dollars. A probabilistic analysis was used, and the model parameters were varied in a sensitivity analysis.

Results

The results indicate that use of the 21-gene rs assay was less costly ($432 less) and more effective (0.22 qalys) than current practice. The probabilistic analysis revealed that 70% of the 10,000 simulated incremental cost-effectiveness ratios were in the southeast quadrant. The results were sensitive to the probability of a low rs and to the probability of receiving chemotherapy in the low-risk rs category and in current practice.

Conclusions

Use of the 21-gene rs assay could be a cost-effective strategy for Ontario patients with estrogen receptor-positive, her2-negative early bca and 1-3 positive lns.

MicroRNA-377 suppresses initiation and progression of esophageal cancer by inhibiting CD133 and VEGF

Esophageal cancer is one of the most lethal cancers worldwide with poor survival and limited therapeutic options. The discovery of microRNAs created a new milestone in cancer research. miR-377 is located in chromosome region 14q32, which is frequently deleted in esophageal squamous cell carcinoma (ESCC), but the biological functions, clinical significance and therapeutic implication of miR-377 in ESCC are largely unknown. In this study, we found that miR-377 expression was significantly downregulated in tumor tissue and serum of patients with ESCC. Both tumor tissue and serum miR-377 expression levels were positively correlated with patient survival. Higher serum miR-377 expression was inversely associated with pathologic tumor stage, distant metastasis, residual tumor status and chemoradiotherapy resistance. The roles of miR-377 in suppressing tumor initiation and progression, and the underlying molecular mechanisms were investigated. Results of in vitro and in vivo experiments showed that miR-377 overexpression inhibited the initiation, growth and angiogenesis of ESCC tumors as well as metastatic colonization of ESCC cells, whereas silencing of miR-377 had opposite effects. Mechanistically, miR-377 regulated CD133 and VEGF by directly binding to their 3' untranslated region. Moreover, systemic delivery of formulated miR-377 mimic not only suppressed tumor growth in nude mice but also blocked tumor angiogenesis and metastasis of ESCC cells to the lungs without overt toxicity to mice. Collectively, our study established that miR-377 plays a functional and significant role in suppressing tumor initiation and progression, and may represent a promising non-invasive diagnostic and prognostic biomarker and therapeutic strategy for patients with ESCC.

Chronic Granulomatous Disease Due to Neutrophil Cytosolic Factor (NCF2) Gene Mutations in Three Unrelated Families

Chronic granulomatous disease (CGD) is an inheritable and genetically heterogeneous disease resulting from mutations in different subcomponents of the NADPH oxidase system. Mutations in the NCF2 gene account for <5% of all cases of CGD. We analyzed the clinical and laboratory findings of CGD with mutations in the NCF2 gene from amongst our cohort of CGD patients. A homozygous mutation (c.835_836delAC, p.T279fsX294), a deletion in NCF2 gene was found in two cases. In the third case, two heterozygous mutations were detected, IVS13-2A>T on one allele and c.1099C>T (p.) on the other allele. The mother of this child was a carrier for the IVS13-2A>T mutation. All three cases had colitis, and it was the initial symptom in two patients. One of the patients also developed a lung abscess due to Nocardia cyriacigeorgica.

Ancestral whole-genome duplication in the marine chelicerate horseshoe crabs

Whole-genome duplication (WGD) results in new genomic resources that can be exploited by evolution for rewiring genetic regulatory networks in organisms. In metazoans, WGD occurred before the last common ancestor of vertebrates, and has been postulated as a major evolutionary force that contributed to their speciation and diversification of morphological structures. Here, we have sequenced genomes from three of the four extant species of horseshoe crabs-Carcinoscorpius rotundicauda, Limulus polyphemus and Tachypleus tridentatus. Phylogenetic and sequence analyses of their Hox and other homeobox genes, which encode crucial transcription factors and have been used as indicators of WGD in animals, strongly suggests that WGD happened before the last common ancestor of these marine chelicerates >135 million years ago. Signatures of subfunctionalisation of paralogues of Hox genes are revealed in the appendages of two species of horseshoe crabs. Further, residual homeobox pseudogenes are observed in the three lineages. The existence of WGD in the horseshoe crabs, noted for relative morphological stasis over geological time, suggests that genomic diversity need not always be reflected phenotypically, in contrast to the suggested situation in vertebrates. This study provides evidence of ancient WGD in the ecdysozoan lineage, and reveals new opportunities for studying genomic and regulatory evolution after WGD in the Metazoa.

Psychiatric Morbidity in Chinese Adults with Type 1 Diabetes in Hong Kong

OBJECTIVES

To determine the prevalence of psychiatric morbidity and identify the correlates, as well as to evaluate the effectiveness of the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire to screen for psychiatric morbidity in Chinese adults with type 1 diabetes.

METHODS

Subjects were recruited from a local public diabetes specialist outpatient clinic from August 2013 to January 2014. Demographic and clinical factors were recorded. Psychiatric diagnosis was established using the Chinese-bilingual version of the Structured Clinical Interview for the DSM-IV Axis I disorders. Scores for the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire were compared with the psychiatric diagnosis.

RESULTS

Of the 136 patients, the point prevalence of overall psychiatric, depressive, and anxiety disorders was 39.7%, 23.5%, and 25.7%, respectively. Family history of mental illness, smoking status, history of mental illness, presence of social problems, perceived absence of confidant, presence of neuropathy and hyperlipidaemia, as well as higher level of glycosylated haemoglobin were found to be the associated factors.

CONCLUSION

Psychiatric disorders were common in Chinese adults with type 1 diabetes. Finding out associated factors and using the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire as a screening tool helped to identify patients in a diabetes clinic with psychiatric disorders.

Reconstructive surgery for females with congenital adrenal hyperplasia due to 21-hydroxylase deficiency: a review from the Prince of Wales Hospital

OBJECTIVES

To present the results of feminising genitoplasty done in female patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

DESIGN

Case series.

SETTING

A tertiary referral centre in Hong Kong.

PATIENTS

Female patients with congenital adrenal hyperplasia undergoing corrective surgery for virilisation between 1993 and 2012.

MAIN OUTCOME MEASURES

The operative result was judged with a scoring system (1-3) for four areas: appearance of clitoris, labia and vagina, plus requirement for revision surgery.

RESULTS

A total of 23 female patients with congenital adrenal hyperplasia with a median age of 17.5 (range, 1.5-33.8) years were identified. Of these individuals, 17 presented in the neonatal period and early infancy, of which four had an additional salt-losing crisis. Six patients-including four migrants from mainland China-were late presenters at a median age of 2 (range, 0.5-14) years. Twenty-two patients had corrective surgery at a median age of 2 (range, 1-14) years. Clitoral reduction was performed in all, and further surgery in 21 patients. The additional surgery was flap vaginoplasty in 10 patients, a modified Passerini procedure in six, and a labial reconstruction in five; one patient with prominent clitoris was for observation only. Minor revision surgery (eg mucosal trimming) was required in three patients; a revision vaginoplasty was done in one individual. Of the 23 patients, 18 (78%) with a median age of 20 (range, 9.3-33.8) years participated in the outcome evaluation: a 'good' outcome (4 points) was seen in 12 patients and a 'satisfactory' (5-9 points) result in five patients.

CONCLUSIONS

Nearly three quarters of our cohort (n=17) presented with classic virilising form of 21-hydroxylase deficiency. Only four (25%) patients experienced a salt-losing crisis. Female gender assignment at birth was maintained for all individuals in this group. 'Good' and 'satisfactory' outcomes of surgery were reported in nearly all participants.

Does K-wire position in tension band wiring of olecranon fractures affect its complications and removal of metal rate?

BACKGROUND

Despite the recognised complications of migration of wires and soft tissue irritation, tension band wiring (TBW) remains the gold standard for fixation of displaced, minimally comminuted olecranon fractures. There is much variation in placement of the K-wires with current AO guidance stating that each wire should be drilled through the anterior cortex and then backed up by 1 cm. The aim of this study was to examine the effect of K-wire position (intramedullary vs. transcortical) on stability of the construct and significant local complications.

METHODS

All patients who underwent TBW for an isolated olecranon fracture in our trauma unit between 1/1/2009 and 31/12/2011 were included in this retrospective study. Mean follow-up was 14 months (range 5-29 months). Data was gathered from medical records and radiographs. The outcome measured was removal of metal due to complications such as wound problems or proximal migration of wires as standard practice within out trauma unit.

RESULTS

Sixty-three patients met the inclusion criteria. Forty-seven had an intramedullary compared with 16 with transcortical configuration (ratio 3:1). Nine patients (19%) with intramedullary K-wires required removal of metalwork - seven due to prominent metalwork and two with wound infection. Four patients (25%) with transcortical K-wires required removal of metalwork - three due to prominent metalwork and one with failure of metalwork. There was no significant statistical difference between transcortical and intramedullary K-wire placement with regards to complication rates following tension band wiring of an isolated olecranon fracture requiring removal of metal (Chi squared test with Yates' correction p = 0.89).

CONCLUSION

We concluded that we found no difference in complications or metalwork removal rate in the placement of K-wire in tension band wiring for isolated olecranon fracture. We recognise our study was limited by small numbers and is based on the experience of one trauma unit.

Silencing of Jagged1 inhibits cell growth and invasion in colorectal cancer

Dysregulated Notch signaling has a critical role in the tumorigenesis. Jagged1, a Notch ligand, is overexpressed in various human cancers. Recent studies revealed the involvement of Jagged1 in colorectal cancer (CRC) development. These basic studies provide a promising potential for inhibition of the Notch pathway for the treatment of CRC. Herein, we aimed to investigate the consequences of targeting Jagged1 using shRNA on CRC both in vitro and in vivo to test their potential to inhibit this key element for CRC treatment. We found that downregulation of Jagged1 with lentiviral Jagged1-shRNA resulted in decreased colon cancer cell viability in vitro, most likely mediated through reduced cell proliferation. Importantly, Jagged1 knockdown induced G₀/G₁ phase cell cycle arrest, with reduced Cyclin D1, Cyclin E and c-Myc expression. Silencing of Jagged1 reduced the migration and invasive capacity of the colon cancer cells in vitro. Furthermore, colon cancer cells with knockdown of Jagged1 had much slower growth rate than control cells in a xenograft mouse model in vivo, with a marked downregulation of cell proliferation markers (PCNA, Ki-67, and c-Myc) and metastasis markers (MMP-2 and MMP-9). These findings rationalize a mechanistic approach to CRC treatment based on Jagged1-targeted therapeutic development.

Under pressure: a contribution to the pathogenesis of acquired ileal atresia

An acquired ileal atresia is a rare occurrence. A 3-week-old neonate is presented, who developed postnatally a type 2 ileal atresia and an ileal stenosis within a pre-existing internal hernia secondary to an adhesion band. The literature reports a total of eight cases (4 females) with acquired ileal atresia in babies ranging in age from 3 weeks to 2 years (median 4 months). Mechanical forces (eg, adhesion band, intussusception and volvulus) onto the intestine are most frequently (75%) implicated as the primary event. The distal ileum is most often affected and a type 3A atresia is identified in six of eight (75%) cases.

Positive influence of L-carnitine on the different muscle fibres types of racing pigeons

Succinate dehydrogenase (SDH), Ca(2+) ATPase, Lactate dehydrogenase (LDH), are involved in energy metabolism. These enzymes can be used as indicators of the energy capacity of aerobic cells. The study investigated the effects of L-carnitine supplementation on M. pectoralis superficialis, M. pectoralis profundus, M. extensor carpi radialis muscle and M. flexor carpi ulnaris. Twenty-eight racing pigeons hatched at the same time were divided randomly into three groups. Eight pigeons, which were used as the control group, were sacrificed at 92-day old. The remaining twenty pigeons continued training until they reached 157-day old, with half the pigeons getting 25 mg/head/day of L-carnitine, while the other half given the same amount of water. The pigeons were assessed by histochemical methods and reverse transcription polymerase chain reaction (RT-PCR). To assess influence of L-carnitine on muscle fibre composition and the performance of three genes' mRNA, this study applied SDH localization, SDH, Ca(2+) ATPase and LDH mRNA expression to examine the results after oral administration of L-carnitine in vivo in racing pigeons. The results showed that L-carnitine significantly elevated the amount of white muscle fibre type IIa (p < 0.05). The mRNA expression quantities of SDH and LDH gene was higher via RT-PCR method. However, the expression of Ca(2+) ATPase remains similar. In conclusion, appropriate oral administration of L-carnitine of 25 mg/pigeon/day will result in an improvement of muscles related to flying.

Hitching the gallbladder in laparoscopic-assisted cholecysto-cholangiography: a simple technique

Neonatal cholestatic disorder in the late neonatal period requires often cholangiography to differentiate between biliary atresia and other causes of prolonged neonatal jaundice. A simplified method of a laparoscopic-assisted cholecysto-cholangiography is presented. Retrospective chart review was conducted of all patients who from May 2002 to April 2012 underwent a laparoscopic-assisted cholecysto-cholangiography with routine fixation of the fundus of the gallbladder to the lateral aspect of the abdominal wall. A total of 18 infants (8 boys) aged 41-104 (median 64) days underwent laparoscopic-assisted cholecysto-cholangiography for prolonged jaundice. The technique identified ten cases of a patent bile duct system and eight biliary atresias. (Thirty-two cases of suspected biliary atresia were confirmed by laparoscopy alone.) Two cases required suturing of a bile leak at the puncture site. Hitching the gallbladder to the lateral abdominal wall is a simple method allowing an optimal radiographic assessment of the extra- and intra-hepatic bile duct anatomy.

Prevalence of abnormal Papanicolaou smears in female sex workers in Hong Kong

OBJECTIVE. To investigate the prevalence of pre-cancerous uterine cervix lesions as detected in Papanicolaou (Pap) smears from female sex workers in Hong Kong. DESIGN. Retrospective analysis of laboratory records. SETTING. Private anatomical pathology laboratory, Hong Kong. PATIENTS. Female sex workers undergoing Pap smear examinations at two non-governmental organisations between 2006 and 2012. MAIN OUTCOME MEASURES. Detection of pre-cancerous uterine cervical conditions and their management. RESULTS. A total of 2697 satisfactory Pap smears from female sex workers were performed during the study period from 2006 to 2012. In these subjects, the point prevalence of low-grade squamous intraepithelial lesion and atypical squamous cells of unknown significance was 10.12% (compared with 3.92% for the general population during the same period), whereas that of high-grade squamous intraepithelial lesions and atypical squamous cells of unknown significance with or without high-grade intraepithelial lesions was 2.22% (compared with 0.54% in the general population). For both categories of lesions, the higher prevalence among female sex workers than in the general population was statistically significant. Most patients who had abnormal Pap smears received proper referrals and follow-up management according to recommended guidelines. CONCLUSIONS. Female sex workers in Hong Kong as a group had a significantly higher prevalence of abnormal Pap smears than the general population. Non-governmental organisations providing free-of-charge screening services to these women helped early detection and proper follow-up for those who had abnormal Pap smears, whilst also increasing their awareness of women's health issues.

Clinicopathological study of renal biopsies after liver transplantation

OBJECTIVE

To perform a clinicopathological study of patients having renal biopsies after liver transplantation.

DESIGN

Case series. SETTING; Queen Mary Hospital, Hong Kong.

PATIENTS

All post-liver transplantation patients who had a renal biopsy in the period from January 2000 to December 2010.

RESULTS

Eleven renal biopsies were retrieved for review from 10 patients with liver transplantation. The male-to-female ratio was 9:1 (age range, 47-63 years). The median liver transplant-to-renal biopsy interval was 1590 (range, 102-3699) days. The predominant histological changes were interstitial fibrosis and tubular atrophy. Diabetic nephropathy (n=6) and immunoglobulin A nephropathy (n=4) were the commonest glomerulopathies. Only one patient had chronic calcineurin inhibitor nephrotoxicity. With a mean follow-up of 53 months, three patients died 2 to 53 months post-renal biopsy. All surviving patients had chronic renal impairment. Five patients developed end-stage renal failure and four had significant persistent proteinuria.

CONCLUSION

Renal pathology was variable after liver transplantation; most biopsies showed complex renal lesions, whilst calcineurin inhibitor nephrotoxicity was rare. The recognition of kidney histology attributable to metabolic derangements after liver transplantation is potentially important in the interpretation of renal biopsy specimens and patient management. The renal outlook of this group of patients is guarded.

Reliability of acute illness dihydrorhodamine-123 testing for chronic granulomatous disease

BACKGROUND

Dihydrorhodamine (DHR) flow cytometric analysis is used to evaluate granulocyte oxidative bursts and is the test of choice for the diagnosis of chronic granulomatous disease (CGD). We present the clinical and DHR test profiles of five subjects assessed during and after acute illness.

METHODS

This was a retrospective report of the findings of five out of a total of one hundred and seventeen patients, whose blood was sent to the laboratory for dihydrorhodamine-123 flow cytometry testing between January 2005 and December 2010. Using whole blood technique and stimulation using phorbol myristate acetate, the results of DHR were expressed as stimulation index and coefficient of variation of histograms of stimulated cells and compared with healthy controls. DHR tests were repeated when the patients had recovered and were clinically well.

RESULTS

These five patients showed abnormal DHR test results during their acute illness, with a stimulation index (SI) lower (p = 0.009) and coefficient of variation (CV) higher (p = 0.009) than controls. The DHR profiles repeated when patients had recovered showed normalization of tests with no significant difference for SI (p = 0.602) and CV (p = 0.917) compared to controls. Wilcoxon Signed Rank tests showed a significant improvement in SI (p = 0.043) and CV (p = 0.043) upon recovery. On follow up, all five patients were well, with no further severe or atypical infections.

CONCLUSIONS

DHR may be transiently abnormal during acute illness, and may therefore not be reliable when assessed during an acute illness. If these subjects had CGD, it would be of a hypomorphic variant that has not previously been described.

Giant urethral diverticulum calculus presenting as scrotal abscess

We report herein a patient with a urethral calculus associated with urethral diverticulum. A 39-year-old man presented with scrotal swelling and acute retention of urine. Computed tomography of the pelvis and cystoscopy demonstrated a giant calculus in the proximal penile urethra. Emergency in-situ lithotripsy was performed. Complete stone clearance was achieved and a large urethral diverticulum was encountered. The rare occurrence of urethral diverticulum and associated stone disease were discussed.

Single-incision laparoscopic cholecystectomy: from four wounds to one

OBJECTIVE

To review the initial results and surgical outcomes of single-incision laparoscopic cholecystectomy.

DESIGN

Prospective case series.

SETTING

A university teaching hospital and a regional hospital in Hong Kong.

PATIENTS

All patients undergoing single-incision laparoscopic cholecystectomy from August 2009 to March 2011.

RESULTS

Fifty patients underwent single-incision laparoscopic cholecystectomy during the study period. The indications for surgery included symptomatic gallstones (n=43) and gallbladder polyps (n=7). The mean operating time was 78 (standard deviation, 24) minutes. Forty-five of the patients successfully underwent single-incision laparoscopic cholecystectomy, giving a success rate of 90%. In the remaining five patients, additional working ports were constructed to obtain better exposure and dissection around Calot's triangle. On comparing the results of the initial 25 cases to the subsequent 25 cases, in the latter group the operating time was significantly shorter (86 vs 71 minutes; P=0.02), and the success rate was higher (80% vs 100%; P=0.05). During the median follow-up period of 6.8 months, four patients had complications, which included: postoperative urinary retention (n=2), one each with a haematoma and an incisional hernia. No patient endured bile duct injury, postoperative bile leakage, or haemorrhage in our series.

CONCLUSION

Single-incision laparoscopic cholecystectomy is feasible and safe for treatment of uncomplicated gallbladder diseases. There was a reduction in the operating time and increase in success rate with accumulation of experience. Nevertheless, surgeons should be cautious about the potential risks of this new technique.

A novel CYBB mutation with the first genetically confirmed case of chronic granulomatous disease in South Africa

A case of a child with chronic granulomatous disease (CGD) presenting with recurrent mycobacterial infections and invasive Aspergillus fumigatus disease is described. Genetic analysis confirmed X-linked CGD with a novel mutation in exon 10 of the CYBB gene - the first South African report of genetically confirmed CGD.

Tuberculosis of gallbladder with candidiasis, a rare entity

Gallbladder tuberculosis (GT) is an extremely rare condition. This is thought to be due to the protective property of bile against the infection. Clinical and radiological diagnosis of GT is difficult. We describe a case of GT who initially presented to us with jaundice, a right hypochondrial mass and computed tomographic findings suggestive of gallbladder empyema. Diagnosis was made from histopathological examination of the resected gallbladder which revealed epitheloid granulomas with caseating necrosis and presence of Langhan's giant cells. From a literature search and to the best of our knowledge, this is the first GT to be reported in South East Asia.

Phaeochromocytoma in the Hong Kong Chinese population

OBJECTIVE

To review the clinical manifestations of phaeochromocytoma in a Hong Kong Chinese population.

DESIGN

Retrospective review. SETTING. Five public hospitals in Hong Kong.

PATIENTS

Seventeen patients with operated phaeochromocytoma between 1994 and 2003 were reviewed retrospectively.

RESULTS

Six patients (35%) were men, 11 (65%) were women. The mean age at presentation was 47 (range, 17-72) years. The diagnosis post-presentation was delayed by 1 to 132 months. Over 70% of the patients had hypertension. The most frequent symptoms were headache (53%), palpitations (53%), and sweating (41%); all these symptoms were present in 24% of the patients. Four (24%) had hereditary phaeochromocytoma/paraganglioma syndrome. The sensitivity of 24-hour urinary catecholamine measurements was 82%. Mean urinary adrenaline and noradrenaline concentrations were respectively 7- and 8-fold greater than the upper reference limits. Computed tomography and metaiodobenzylguanidine scintigraphy were the most widely used means for tumour localisation (sensitivity, 100% and 87% respectively). Approximately 65% of the patients had intra-adrenal tumours; 53% were on right side, 18% were bilateral. All the patients were prescribed phenoxybenzamine (dosage range, 20-120 mg/day) preoperatively. Two thirds of the patients had improved blood pressure 1 year after the operation. No malignancy was reported after a mean follow-up period of 7 years.

CONCLUSION

Our series of patients with phaeochromocytomas commonly had a high frequency of normotension and extra-adrenal tumours. A high index of clinical suspicion and appropriate biochemical investigations are necessary to make the diagnosis, especially for patients manifesting adrenal incidentaloma and extra-adrenal lesion.

Accumulation of p53 protein in inverted transitional cell papilloma of the urinary bladder

Aims-To study the possible accumulation of p53 protein in inverted papilloma of the urinary bladder.Methods-Formalin fixed, paraffin wax embedded sections from 14 cases of inverted papilloma of the urinary bladder were studied retrospectively. Accumulation of p53 was detected by immunohistochemistry using a mouse monoclonal antibody directed against p53. p53 protein reactivity was scored as follows: 0 = 10%; 1 = 10% to <30%; 2 = 30% to <50%; and 3 = >50% of cells p53 positive.Results-The 14 sections were scored as follows: 3 in four cases; 2 in four cases; 1 in one case; and 0 in five cases. Overall, nine (64%) of the 14 cases were positive for p53 protein.Conclusions-The accumulation of p53 protein in inverted papilloma of the urinary bladder suggests that p53 may have has an important role in the neoplastic process of this tumour. However, the benign nature of inverted papillomas suggests that p53 protein accumulation is not related to tumour invasiveness and metastasis. p53 reactivity cannot be used as a marker of malignancy for urothelial neoplasia. Further studies are required to determine the role of p53 protein in the oncogenesis of urothelial neoplasms.

Comparative analysis of BU and CY versus CY and TBI in full intensity unrelated marrow donor transplantation for AML, CML and myelodysplasia

We retrospectively compared clinical outcomes in 1593 T-replete unrelated donor (URD) marrow transplant recipients with AML, MDS and CML who received myeloablative conditioning regimens of either BU and CY (BuCy), standard-dose Cy/TBI (1000-1260 cGy) or high-dose Cy/TBI (1320-1500 cGy). Subjects were drawn from patients transplanted between 1991 and 1999 facilitated by the National Marrow Donor Program. Patients who received high-dose Cy/TBI regimens were slightly younger, more likely to receive a mismatched transplant and to have intermediate or advanced disease compared with patients in the BuCy or standard-dose TBI group. Neutrophil recovery was significantly higher in the standard-dose CY/TBI group compared with the high-dose Cy/TBI or BuCy group. Patients who received the high-dose Cy/TBI regimen had an increased risk of developing grades III-IV aGVHD when compared with the control group who received BuCy (P = 0.011). OS, disease-free survival (DFS), TRM and relapse were not significantly different between any of the regimens. We conclude that BuCy, standard-dose and high-dose Cy/TBI regimens have equivalent efficacy profiles for OS, DFS, TRM and relapse risk in patients undergoing T-replete URD marrow transplantation for AML, CML and MDS.

Circulatory collapse in a patient with gastrinoma after metoclopramide administration

A patient who was given metoclopramide for vomiting and diarrhoea developed circulatory collapse with his blood pressure dropping to 50/20 mm Hg. A gastrinoma was diagnosed histologically. The extent of the tumour was defined by octreotide scanning and magnetic resonance imaging. Metoclopramide was again given for colicky abdominal pain and the patient developed circulatory collapse a second time. A laparotomy involving extensive resection of the tumour was performed. The MEN1 mutation was not detected in blood or tumour tissue. Follow-up octreotide scanning did not show any residual tumour. Possible causes for the circulatory collapse are discussed. Our case is probably the first patient with gastrinoma to develop circulatory collapse after being given metoclopramide.

Imperforate hymen: cause of lower abdominal pain in teenage girls

Imperforate hymen is a relatively rare congenital anomaly. However, it is not an uncommon cause of lower abdominal pain presenting in teenage girls. Without careful history taking and thorough examination, the condition can be missed easily. We report an imperforate hymen presenting as abdominal pain in three teenage girls aged 12, 12 and 13 years, respectively, within a six-month period. The presentation was reviewed and the various types of hymenotomy were discussed.

Usage of a fixed dose of radioactive iodine for the treatment of hyperthyroidism: one-year outcome in a regional hospital in Hong Kong

OBJECTIVES

To evaluate the efficacy of a fixed dose of radioactive iodine (131-I) in the treatment of thyrotoxicosis, and to identify risk factors associated with treatment failure.

DESIGN

Retrospective study.

SETTING

Thyroid Clinic of a regional hospital in Hong Kong.

PATIENTS

Patients receiving their first dose of radioactive iodine for the treatment of thyrotoxicosis during the inclusive period September 1999 to August 2004.

MAIN OUTCOME MEASURES

Relapse rate and time to relapse.

RESULTS

A total of 113 patients received a fixed dose of 5 mCi (185 MBq), 6 mCi (222 MBq), 8 mCi (296 MBq), and 10 mCi (370 MBq) 131-I in a proportion of 1:6:71:35. At 1 year, 42 (37%) of the patients had relapsed, of which 69% received a second 131-I dose. The median time to relapse after first receiving 131-I was 4 months. At 1 year, the remaining 71 (63%) of the patients were successfully treated; 46 (41%) were euthyroid, and 25 (22%) had became permanently hypothyroid. Basal free thyroxine level and goitre size were significantly associated with a relapse rate after a single dose of 131-I; larger goitres showed a trend towards high rates of relapse. Patients pretreated with propylthiouracil had a higher rate of relapse during the first year after radioactive iodine than those pretreated with carbimazole, but the difference was not significant when combined with other pretreatment variables.

CONCLUSIONS

A single fixed dose of radioactive iodine is a simple, safe, and effective treatment for hyperthyroidism. High basal free thyroxine concentration and large goitre size are associated with higher chance of relapse. Higher radioiodine doses may be considered to improve the cure rate.

Co-morbidities of patients with knee osteoarthritis

OBJECTIVES

To study the co-morbidities of general practice patients with knee osteoarthritis.

DESIGN

Cross-sectional study.

SETTING

Two private general practice clinics in Hong Kong.

PATIENTS

All patients presenting at the two clinics were screened for osteoarthritis of the knee based on American College of Rheumatology diagnostic criteria. Patients with osteoarthritis then completed a semi-instructed questionnaire.

RESULTS

A total of 455 patients were recruited into the study. Over half (56%) had knee pain plus more than three other diagnostic criteria. Almost all (95%) of the patients with osteoarthritis had no signs of inflammation at the time of screening. Their mean age was 54 years. Overall, 78% of them had at least one musculoskeletal co-morbidity and 82% had at least one non-musculoskeletal co-morbidity. On average they had 3.2 co-morbidities, of which 1.7 were musculoskeletal and 1.5 were non-musculoskeletal. Problems related to the back, upper limbs, neck, and lower limbs were the four most common musculoskeletal co-morbidities, of which neck problems were significantly more common among younger patients (55 years or below) [odds ratio for older to younger patients was 0.62; 95% confidence interval, 0.4-0.9]. The four commonest non-musculoskeletal co-morbidities were cardiovascular, gastro-intestinal, respiratory, and endocrine, of which cardiovascular diseases (odds ratio=8.76; 95% confidence interval, 5.6-13.7), endocrine problems (4.56; 2.8-7.4), and central nervous system diseases (12.74; 1.6-102.8) were significantly likely among older patients (more than 55 years).

CONCLUSION

General practitioners should be alert to the presence of co-morbidities when managing patients with osteoarthritis of the knee.

Scan-directed unilateral neck exploration for primary hyperparathyroidism: eight-year results from a regional hospital

OBJECTIVE

To determine the results of scan-directed unilateral neck exploration for primary hyperparathyroidism.

DESIGN

Retrospective study.

SETTING

Regional hospital, Hong Kong.

PATIENTS

Patients who underwent parathyroid surgery for primary hyperparathyroidism between January 2000 and December 2007 were included.

MAIN OUTCOME MEASURES

The demographic, imaging, biochemical, and pathological data, as well as surgical outcomes were analysed according to the treatment received.

RESULTS

A total of 78 patients were included in this study; 65 underwent unilateral neck exploration with image guidance by ultrasonography or technetium Tc99m sestamibi scan. The scan sensitivity for localising the side of the lesion was 66% for ultrasound scans, 71% for technetium Tc99m sestamibi scans, and 85% for both scans used in combination. Pathological analysis showed that 95% (74/78) of the patients had a single parathyroid adenoma, two had hyperplasia of four glands, one had a double adenoma, and one a parathyroid carcinoma. Among the patients undergoing scan-directed unilateral neck exploration, one defaulted follow-up, while the remaining 64 patients achieved normal calcium levels at a median follow-up of 6 months.

CONCLUSION

Scan-directed unilateral neck exploration is a safe alternative form of treatment for patients with primary hyperparathyroidism, with a cure rate similar to conventional therapy.

Rapamycin prevents the development of nephritis in lupus-prone NZB/W F1 mice

Rapamycin is a potent immunosuppressive drug currently used mainly for rejection prophylaxis in renal transplantation. The aim of this study was to determine the effect of rapamycin treatment on the development of nephritis in lupus-prone New Zealand Black/White F1 (NZB/W F1) mice. Twelve-week-old female NZB/W F1 mice were treated with rapamycin (3 mg/kg body weight) or saline once daily by oral gavage for 20 weeks. The severity of nephritis was assessed by clinical and biochemical parameters, renal histology, immunohistochemistry and gene expression studies. Rapamycin treatment markedly reduced proteinuria, improved renal function, decreased serum anti-double stranded DNA antibody levels and diminished splenomegaly. Kidney sections from saline-treated mice showed marked mesangial proliferation, tubular dilation with protein cast deposition and interstitial inflammatory cell infiltration. Rapamycin-treated mice had near normal renal histology, with marked reduction in glomerular immune deposition and the infiltration by T cells, B cells and macrophages. Rapamycin treatment was associated with down-regulation of intra-renal expression of monocyte chemoattractant protein-1 (MCP-1) mRNA and protein. We conclude that rapamycin is highly effective in preventing the development of nephritis in NZB/W F1 mice. The beneficial effects of rapamycin are mediated through inhibition of lymphoproliferation and reduced MCP-1 expression.

Characteristics of false-negative ThinPrep cervical smears in women with high-grade squamous intraepithelial lesions

OBJECTIVE

To examine the cellular characteristics and other possible factors affecting the correct prediction of ThinPrep cervical smears from patients with high-grade squamous intraepithelial lesions.

DESIGN

Retrospective study.

SETTING

Private anatomical pathology service, Hong Kong.

PATIENTS

Patients (n=98) with biopsy-confirmed high-grade squamous intraepithelial lesion of the uterine cervix encountered between 2004 and 2006.

MAIN OUTCOME MEASURES

Correct prediction of the cervical ThinPrep Papanicolaou tests.

RESULTS

There were no significant differences in age, hormonal status, degree of inflammation, and the presence or absence of endocervical/metaplastic cells between the true-positive and false-negative groups. There was a significant difference in the number of abnormal cells present and the screening time between the two groups. Approximately 79% (34/43) false-negative smears had 100 or less abnormal cells, while only 11% (5/45) true-positive smears had 100 or less abnormal cells (P<0.001). The true-positive smears were also more likely to contain koilocytic cells and abnormal cells with hyperchromatic nuclei.

CONCLUSIONS

The number of abnormal cells present, the presence or absence of koilocytic cells, and the presence or absence of abnormal cells with nuclear hyperchromasia appeared to be independent factors affecting the correct prediction of smears from patients with high-grade squamous intraepithelial lesions.

The use of laparoscopy in the management of Littre's hernia in children

Littre's hernia is a rare complication of Meckel's diverticulum. It was originally defined as 'the presence of a Meckel's diverticulum in any hernia sac' by Rieke in 1841. It is difficult to diagnose before surgery. With the advances in the development of laparoscopic surgery in children, diagnosis of this rare condition, together with subsequent repair of Littre's hernia and Meckel's diverticulectomy can be performed by laparoscopy. We herein report the use of laparoscopy in the management of two boys with Littre's hernia, including one with incarcerated hernia.

Selection of cord blood unit(s) for transplantation

Selection of cord blood (CB) units for transplantation involves combining both cell dose and HLA matching as independent yet overlapping variables. Cell dose and cell yield at the time of transplant are critical given that the transplants are being performed with minimal cells for reliable engraftment. In transplants for malignant disorders, the greater allogenicity and lower relapse rate associated with the less well-matched units balance any benefit of better HLA matching on TRM. The only factor that has repeatedly been associated with improved outcome post CB transplant is cell dose. The CB inventories are rapidly increasing in size and the quality of CB units being banked (larger, better characterized) is improving. With this, some of our current limitations in CB availability will soon become moot. Explorations into CB expansion and multiple CB unit transplants are addressing the limited cell doses attainable with a single CB collection. At this point, one must conclude that bigger is better when selecting CB units for transplantation.

Urinary bladder pheochromocytoma, an extremely rare tumor in children: case report and review of the literature

We report a case of pheochromocytoma in the urinary bladder of a 14-year-old girl who presented with headache and palpitation after voiding. This is an extremely rare condition in pediatric age group and thus can be missed easily. This case is the seventh case reported in the reviewed literature.

Decreased adhesiveness, resistance to anoikis and suppression of GRP94 are integral to the survival of circulating tumor cells in prostate cancer

The presence of circulating tumor cells (CTC) is common in prostate cancer patients, however until recently their clinical significance was unknown. The CTC stage is essential for the formation of distant metastases, and their continuing presence after radical prostatectomy has been shown to predict recurrent or latent disease. Despite their mechanistic and prognostic importance, due both to their scarcity and difficulties in their isolation, little is known about the characteristics that enable their production and survival. The aim of this study was to investigate the molecular mechanisms underlying the survival of CTC cells. A novel CTC cell line from the bloodstream of an orthotopic mouse model of castration-resistant prostate cancer was established and compared with the primary tumor using attachment assays, detachment culture, Western blot, flow cytometry and 2D gel electrophoresis. Decreased adhesiveness and expression of adhesion molecules E-cadherin, beta4-integrin and gamma-catenin, together with resistance to detachment and drug-induced apoptosis and upregulation of Bcl-2 were integral to the development of CTC and their survival. Using proteomic studies, we observed that the GRP94 glycoprotein was suppressed in CTC. GRP94 was also shown to be suppressed in a tissue microarray study of 79 prostate cancer patients, indicating its possible role in prostate cancer progression. Overall, this study suggests molecular alterations accounting for the release and survival of CTC, which may be used as drug targets for either anti-metastatic therapy or the suppression of latent disease. We also indicate the novel involvement of GRP94 suppression in prostate cancer metastasis.