Stepwise self-assembly of a discrete molecular honeycomb using a multitopic metallo-organic ligand

A molecular bismetallo-hexagon and a honeycomb fractal have been assembled with multiple tpy-M²⁺-tpy connectivities. The key metallo-organic ligand was created by a reaction on complex strategy.

Metal ion-modulated self-assembly of pseudo-suit[3]anes using crown ether-based terpyridine metalloprisms

The host–guest inclusion rates of two metallo-supramolecular pseudo-suit[3]anes are modulated by metal–terpyridine interactions in the metallo-suits.

Self-assembly of triangular metallomacrocycles using unsymmetrical bisterpyridine ligands: isomer differentiation via TWIM mass spectrometry

Three unsymmetrical, 60°-bended bisterpyridine ligands with varying phenylene spacer lengths have been synthesized via the Suzuki-Miyaura coupling reactions. Their self-assembly processes were found to be strongly dependent on the ligand geometry. Upon complexation with Zn(II) ions, only 2,4''-di(4'-terpyridinyl)-1,1':4',1''-terphenyl underwent self-selection to give a trinuclear metallomacrocycle with perfect heteroleptic connectivity and the other two afforded a mixture of constitutional isomers. The metallosupramolecular assemblies were characterized by NMR spectroscopy, electrospray mass spectrometry (ESI MS), and single-crystal X-ray diffraction. In particular, the identification of isomeric architecture was accomplished using tandem mass spectrometry (MS(2)) coupled with traveling wave ion mobility mass spectrometry (TWIM MS).

Allergy in Hong Kong: an unmet need in service provision and training

Many children in Hong Kong have allergic diseases and epidemiological data support a rising trend. Only a minority of children will grow out of their allergic diseases, so the heavy clinical burden will persist into adulthood. In an otherwise high-quality health care landscape in Hong Kong, allergy services and training are a seriously unmet need. There is one allergy specialist for 1.5 million people, which is low not only compared with international figures, but also compared with most other specialties in Hong Kong. The ratio of paediatric and adult allergists per person is around 1:460 000 and 1:2.8 million, respectively, so there is a severe lack of adult allergists, while the paediatric allergists only spend a fraction of their time working with allergy. There are no allergists and no dedicated allergy services in adult medicine in public hospitals. Laboratory support for allergy and immunology is not comprehensive and there is only one laboratory in the public sector supervised by accredited immunologists. These findings clearly have profound implications for the profession and the community of Hong Kong and should be remedied without delay. Key recommendations are proposed that could help bridge the gaps, including the creation of two new pilot allergy centres in a hub-and-spoke model in the public sector. This could require recruitment of specialists from overseas to develop the process if there are no accredited allergy specialists in Hong Kong who could fulfil this role.

Synthesis and isolation of an acyclic tridentate bis(pyridine)carbodicarbene and studies on its structural implications and reactivities

The simple synthetic development of acyclic pincer bis(pyridine)carbodicarbene is depicted herein. Presented is the first isolated structural pincer carbodicarbene with a C-C-C angle of 143°, larger than the monodentate framework. More importantly, theoretical analysis showed that this carbodicarbene embodies a more allene-like character. Palladium complexes supported by this pincer ligand are active catalysts for Heck-Mizoroki and Suzuki-Miyaura coupling reactions.

Social obstetrics: non-local expectant mothers admitted through accident and emergency department in a public hospital in Hong Kong

OBJECTIVES

To review the pregnancy outcomes of non-booked, non-local pregnant women delivering in Kwong Wah Hospital via admission to the Accident and Emergency Department 1 year after the announcement by the Hospital Authority to stop antenatal booking for non-eligible persons; and to perform a literature review of local studies about non-eligible person deliveries over the last decade.

DESIGN

Case series.

SETTING

A public hospital in Hong Kong.

PARTICIPANTS

All women who held the People's Republic of China passport or the two-way permit and those non-eligible persons whose spouses were Hong Kong Identity Card holders, who delivered in Kwong Wah Hospital from 1 April 2011 to 31 March 2012.

RESULTS

Overall, 219 women who were non-eligible persons delivered 221 live births during the study period. Compared with the annual statistics of Kwong Wah Hospital in 2011, non-local mothers were of higher parity; more likely to have hypertensive disease (including pre-eclamptic toxaemia), preterm deliveries (ie at <37 weeks), babies needing admission to the special care baby unit, and macrosomic babies (ie weighing >4.0 kg). The rates of induction of labour and caesarean section were lower in this group. There was no significant difference in the maternal and neonatal outcomes between women who had no booking and those who had a booking in another Hospital Authority or private hospital. There were many incidents of near-miss obstetric complications or suboptimally managed obstetric conditions due to lack of well-structured and continuous antenatal care in this group of non-eligible persons.

CONCLUSION

Non-eligible person delivering babies in Hong Kong has become a social obstetrics phenomenon. Despite the introduction of policies, reduction in the number of deliveries (quantity) did not improve the obstetric outcomes (quality). Health care professionals should continue to be prepared for managing the potential near-miss clinical complications in this group of 'travelling mothers'.

Separation and characterization of metallosupramolecular libraries by ion mobility mass spectrometry

The self-assembly of Zn(II) ions and bis(terpyridine) (tpy) ligands carrying 120° or 180° angles between their metal binding sites was utilized to prepare metallosupramolecular libraries with the <tpy-Zn(II)-tpy> connectivity. These combinatorial libraries were separated and characterized by ion mobility mass spectrometry (IM MS) and tandem mass spectrometry (MS(2)). The 180°-angle building blocks generate exclusively linear complexes, which were used as standards to determine the architectures of the assemblies resulting from the 120°-angle ligands. The latter ligand geometry promotes the formation of macrocyclic hexamers, but other n-mers with smaller (n = 5) or larger ring sizes (n = 7-9) were identified as minor products, indicating that the angles in the bis(terpyridine) ligand and within the coordinative tpy-Zn(II)-tpy bonds are not as rigid, as previously believed. Macrocyclic and linear isomers were detected in penta- and heptameric assemblies; in the larger octa- and nonameric assemblies, ring-opened conformers with compact and folded geometries were observed in addition to linear extended and cyclic architectures. IM MS(2) experiments provided strong evidence that the macrocycles present in the libraries were already formed in solution, during the self-assembly process, not by dissociation of larger complexes in the gas phase. The IM MS/MS(2) methods provide a means to analyze, based on size and shape (architecture), supramolecular libraries that are not amenable to liquid chromatography, LC-MS, NMR, and/or X-ray techniques.

Design, synthesis, and traveling wave ion mobility mass spectrometry characterization of iron(II)- and ruthenium(II)-terpyridine metallomacrocycles

New metallomacrocycles composed of 2,2':6',2″-terpyridine (tpy) ligands and Ru(II) or Fe(II) transition metal ions were prepared by stepwise directed assembly and characterized by 2D diffusion NMR spectroscopy (DOSY), electrospray ionization traveling wave ion mobility mass spectrometry (ESI TWIM MS), and molecular modeling. The supramolecular polymers synthesized include a homonuclear all-Ru hexamer as well as heteronuclear hexamer and nonamer with alternating Ru/Ru/Fe metal centers. ESI MS yields several charge states from each supramacromolecule. If ESI is interfaced with TWIM MS, overlapping charge states and the isomeric components of an individual charge state are separated based on their unique drift times through the TWIM region. From experimentally measured drift times, collision cross-sections can be deduced. The collision cross-sections obtained for the synthesized supramacromolecules are in good agreement with those predicted by molecular modeling for macrocyclic structures. Similarly, the hydrodynamic radii of the synthesized complexes derived from 2D DOSY NMR experiments agree excellently with the radii calculated for macrocyclic architectures, confirming the ESI TWIM MS finding. ESI TWIM MS and 2D DOSY NMR spectroscopy provide an alternative approach for the structural analysis of supramolecules that are difficult or impossible to crystallize, such as the large macrocyclic assemblies investigated. ESI TWIM MS will be particularly valuable for the characterization of supramolecular assemblies not available in the quantity or purity required for NMR studies.

Ethyl acetate extract of Chinese medicinal herb Sarcandra glabra induces growth inhibition on human leukemic HL-60 cells, associated with cell cycle arrest and up-regulation of pro-apoptotic Bax/Bcl-2 ratio

Sarcandra glabra (Thunb.) Nakai, colloquially known as Caoshanhu, is a Chinese medicinal herb with reported anti-tumor, anti-inflammatory, anti-viral and non-specific immunoenhancing properties. Although the plant has been clinically used for treating a variety of diseases, its bioactive ingredients are largely unknown and its mode of action has never been investigated. In this study, the anti-tumor property of ethyl acetate (EA) extract of S. glabra was investigated by determining its in vitro growth-inhibitory effects on a panel of human cancer cell lines of different histotypes. Growth inhibition of the EA extract on the cancer cells seemed to be selective, and the leukemic HL-60 was found to be the most responsive after 48 h of treatment (IC50=58 microg/ml). Flow cytometric studies further illustrated that the extract might interfere with DNA replication and thus arrested the cell cycle at S phase in the leukemic cells, followed by DNA fragmentation and loss of phospholipid asymmetry in the plasma membrane after 72 h of treatment. Concurrently, the pro-apoptotic Bax/Bcl-2 ratio was also up-regulated by more than 178% of the control level. All these findings suggested that the extract had initiated apoptosis to kill the leukemic cells. Results from this pioneer study help to establish a scientific foundation for future research and development of the bioactive ingredients in EA extract of S. glabra as efficacious anti-cancer agents.

Ia3d cubic mesoporous silicas using EO17MA23 diblock copolymers made from ATRP

Poly(ethylene oxide)-b-poly(methyl acrylate) diblock copolymer (EOmMAn) prepared via an atom transfer radical polymerization (ATRP) approach was used as a template to synthesize Ia3d mesostructured silica with thick walls under acidic conditions.

An easy method to reduce anterior shoulder dislocation: the Spaso technique

OBJECTIVE

To introduce the Spaso technique for reducing anterior shoulder dislocation by reporting the success rate of the Spaso technique performed by junior emergency medicine residents.

DESIGN

Retrospective case series.

SETTING

Urban accident and emergency department.

PARTICIPANTS

Patients with anterior shoulder dislocations.

INTERVENTIONS

The Spaso technique was applied by the emergency medicine residents to reduce anterior shoulder dislocation.

RESULTS

The emergency medicine residents applied the Spaso technique to reduce 16 cases of anterior dislocated shoulder during the study period. The Spaso technique was successful in 14 of 16 cases. The overall success rate was 87.5% (95% CI 60.4, 97.8%). No complications were noted.

CONCLUSION

A new method has been introduced for reduction of anterior shoulder dislocation by reporting the experience of junior residents. The Spaso technique is simple, effective and able to be performed by single operator. Although the sample size was small, the result of the study could provide background information for planning a properly designed randomised controlled trial to evaluate the Spaso technique.

Highly successful long-term outcome of kidney transplantation in Chinese recipients: an enhancing race effect?

We report on 352 cadaveric kidney transplants and 294 living related transplants performed over a 25-yr period among the Chinese population of Hong Kong. There is a marked preference for transplanting male patients, especially from living donors, and we argue that this represents a cultural phenomenon within the Chinese population. The 10-yr graft survivals for related and cadaveric transplants are 86.2% and 67.4%, respectively. These figures are appreciably higher than corresponding figures in Caucasian populations. We show beneficial effects of using cyclosporin A, minimizing the cold ischemia time and avoiding very young and very old donors. There is a clear benefit of transplanting kidneys with zero or one mismatched HLA antigen against the recipient but no stepwise decrease in outcome as the number of mismatched antigens increases. There is close concordance between the outcome of living related grafts with zero, one, and two mismatched haplotypes against the recipient and no observable benefit of haplotype matching. We show that Chinese renal transplant recipients in other centers also have better long-term graft outcome than Caucasians, both for cadaveric and living related transplants. We draw attention to the existence of a detrimental "race effect" in other studies when Black recipients are compared with Caucasians and consider whether an enhancing race effect exists for Chinese or whether the better outcome reflects different underlying diseases in Chinese.

Improved treatment outcome in adult acute lymphoblastic leukemia using the intensive German protocol, a preliminary report

Thirty-nine consecutive patients with acute lymphoblastic leukemia were treated with an intensive chemotherapy protocol. There were 23 males and 16 females with a median age of 37 years (range: 15-65). Eighteen patients had common ALL, seven had pre-B ALL, three early-precursor B ALL, seven T-ALL and four had aberrant expression of myeloid antigens (c-ALL in three and pre-B ALL in one). The median initial leukocyte count was 11.8 x 10(9)/l (range: 0.65-295). Cytogenetic result of the marrow was available in 16 of 39 patients (41 per cent) and showed Philadelphia positivity in six, a normal result in six and one each of t(4,11), t(1,19), hyperdiploidy and del 12p. Hepatosplenomegaly was present in about 20 per cent of the patients. L-Asparaginase-related hepatic toxicity was the commonest toxicity (48.7 per cent) during phase I of induction. Prolonged pancytopenia and hypoplastic death were common during phase II. With the use of growth factors during the neutropenic period of phase II induction, the rate of hypoplastic death was reduced from 40 per cent to 3 per cent. Common causes of treatment failure included early hypoplastic death (27.8 per cent) and leukemia relapses (50 per cent) while primary refractory leukemia, hepatic failure and perforated peptic ulcer contributed to 11.1, 5.5 and 5.5 per cent of the other deaths. A high complete remission (CR) rate (87.4 per cent) was achieved after phase I induction. The median event-free survival (EFS) was 8 months and the 3-year event-free survival was 43 per cent. This result compared favourably to the other regimens previously employed in our institution. In conclusion, satisfactory survival can be achieved with this intensive regimen. Good supportive care was however, essential to minimize toxicities.

A phase II study of single agent paclitaxel in patients at first relapse following initial chemotherapy for breast cancer

This study was initiated to evaluate the safety and efficacy of 3-weekly paclitaxel given at 225 mg/m2 over 3 hours without colony stimulating factor support in patients at their first relapse following adjuvant therapy for breast cancer. Thirty patients were entered into the study; all were assessable for response and toxicity. All patients had received adjuvant/neo-adjuvant chemotherapy; 22 patients had had prior hormonal therapy and 26 previous adjuvant radiotherapy. The group was characterized by a short time to first relapse (median 7.5 months (range 2-43)) and widespread disease, with 22 patients having multiple disease sites including: nodes (43%), skin and soft tissue (43%), liver (40%), lung (37%) and bone (50%). A total of 219 cycles of paclitaxel were given, with a median of eight per patient. The major non-haematological toxicities were: grade 3 alopecia (82% cycles), grade 2/3 arthralgia/myalgia (26%), grade 2/3 fatigue (16%) and grade 2/3 peripheral nervous system toxicity (12%). Haematological toxicity was mainly neutropenia of short duration, with grade 4 counts documented in 16% of cycles. Thrombocytopenia was minimal and there were no significant hypersensitivity reactions. The objective response rate was 60% (95% CI 42.5-77.5) with one complete response and 17 partial responses. The median duration of overall response was 30 weeks (range 15-75+ (95% CI 25-33)) with a median survival time for all patients of 42 weeks (range 1-124+). This study demonstrates that paclitaxel 225 mg/m2 is well tolerated as a 3-hour infusion and can be given safely in an outpatient setting without routine use of granulocyte colony stimulating factor. The response rate is encouraging and shows that this regimen is effective in this poor prognosis patient population.

Human lagochilascariasis treated successfully with ivermectin: a case report

A 15 year old male patient was diagnosed as being infected with the nematode Lagochilascaris minor, presenting as abscesses over the left mastoid region, and invading the temporal bone, mastoid sinuses and possibly the CNS. Surgical drainage and administration of cambendazole and levamisole led to improvement, followed by an early relapse and poor tolerance to the antihelminthic drugs. Repeated doses of ivermectin (an animal preparation) were used for the first time to treat this condition and resulted in complete remission of signs of infection, maintained for 15 months after the end of drug therapy, indicating cure of the disease.

Use of skin staples for fixation of T tubes and drains

Stapled anchorage is safe and effective for T tubes and drains and is preferred to the conventional technique. Significant bile leaks never occur. Three and two staples are recommended for anchoring T tubes and drains, respectively.

Endoscopic sphincterotomy in young patients with choledochal dilatation and a long common channel: a preliminary report

An anomalous elongated pancreaticobiliary common channel encourages reflux up both the biliary tree and the pancreatic ductal system, resulting in progressive choledochal dilatation, cholangitis with ductal calculi, relapsing pancreatitis and malignant change. Transduodenal sphincteroplasty has been used to improve drainage from the abnormal channel. The use of endoscopic sphincterotomy (ES) to establish drainage and minimize the surgical risks is reported in six symptomatic patients with mild choledochal dilatation (common bile duct diameter less than 15 mm), a common channel less than 15 mm in length and a distal stenosis. This was successful in five patients, who have no further symptoms. ES failed in the only patient with an undilated common channel and this patient went on to have open surgery. We believe ES to be safe and effective in the treatment of selected cases of long common channel.

Intestinal obstruction due to axial twisting of bowel in transmesenteric hernia

A baby, born with gastroschisis, had an unrepaired large aperture in the mesocolon close to a short segment of colon. One day, the entire length of bowel proximal to the defect traversed the rent. The free segment of colon was affected by the resulting twist along the long axis of the bowel and became obstructed. A large mesenteric defect, albeit too wide to strangulate the bowel, is not totally innocuous and should always be closed.

Presacral myelolipoma: case report with computed tomographic and angiographic findings

A rare case of presacral myelolipoma in an otherwise healthy 53 year old man is described. His only complaint was lower abdominal discomfort. Full investigation including computed tomography and angiography revealed a well-delineated, heavily calcified, avascular retrorectal mass adhering to the presacral fascia. Histologically the mass showed a mixture of haemopoietic tissue and mature fat cells. Clinically the absence of symptoms and bone involvement served to distinguish this condition from other more sinister presacral lesions, particularly a chordoma.