Aufbau principle of complex open-framework structures of metal phosphates with different dimensionalities

Open-framework metal phosphates occur as one-dimensional (1D) chains or ladders, two-dimensional (2D) layers, and complex three-dimensional (3D) structures. Zero-dimensional monomers have also been isolated recently. These materials are traditionally prepared by hydrothermal means, in the presence of organic amines, but the reactions of amine phosphates with metal ions provide a facile route for the synthesis, and also throw some light on the mode of formation of these fascinating architectures. Careful studies of the transformations of monophasic zinc phosphates of well-characterized structures show that the 1D structures transform to 2D and 3D structures, while the 2D structures transform to 3D structures. The zero-dimensional monomers transform to 1D, 2D, and 3D structures. There is reason to believe that the 0D monomers, comprising four-membered rings, are the most basic structural units of the open-framework phosphates and that after an optimal precursor state, such as the ladder structure, is formed, further building may occur spontaneously. Evidence for the occurrence of self-assembly in the formation of complex structures is provided by the presence of the structural features of the one-dimensional starting material in the final products. These observations constitute the beginning of our understanding of the building-up principle of such complex structures.

Three-dimensional open-framework cobalt(II) phosphates by novel routes

Two new three-dimensional open-framework cobalt phosphates, [C2N2H10]2[Co4(PO4)4]H2O, I, and [C4N3H16]3-[Co6(PO4)5(HPO4)3]H2O, II, have been prepared by the reaction of amine phosphates with Co2+ salts. I could also be prepared by the reaction of the cobalt tris amine complex with H3PO4. The crystal data for I and II are as follows: phosphate I, orthorhombic, space group P2(1)2(1)2(1) (no. 19), a = 10.277 (1) A, b = 10.302 (1) A, c = 18.836 (1) A, V = 1994.2 (2) A3, Z = 4; phosphate II, monoclinic, space group P2(1)/c (No. 14), a = 31.950 (1) A, b = 8.360 (1) A, c = 15.920 (1) A, beta = 96.6 (1) degrees V = 4223.4 (2) A3, Z = 4. The structures of both I and II are constructed from alternating CoO4 and PO4 tetrahedra. The connectivity leads to the formation of eight-membered channels in all the crystallographic directions resembling the aluminosilicate zeolite, merlinoite in the case of I and to a rather large, one-dimensional 16-membered channel in II. Strong hydrogen-bond interactions involving the amine and framework oxygen are present in both I and II.

Perinatal and early surgical outcome for the fetus with hypoplastic left heart syndrome: a 5-year single institutional experience

OBJECTIVES

To review our experience with the prenatal diagnosis of hypoplastic left heart syndrome (HLHS). Our goal was to establish the benchmark for perinatal and early surgical outcome in the current era, from a center with an aggressive surgical approach and a cohort with a high level of intention-to-treat.

METHODS

Outcome was assessed in fetuses with HLHS following stratification into high-risk and standard-risk categories. High risk was defined as the presence of any of the following: extracardiac, genetic or chromosomal anomalies; prematurity of < 34 weeks' gestation; additional cardiac findings such as intact or highly restrictive atrial septum, severe degree of tricuspid regurgitation or severe ventricular dysfunction. Standard risk was defined as absence of these risk factors.

RESULTS

Of 240 fetuses evaluated over 5 years, 162 (67.5%) were in the standard-risk group and 78 (32.5%) were in the high-risk group. Of the 240 sets of parents, 38 (15.8%) chose termination or non-intervention at birth at initial prenatal counseling and 185 of the neonates (77.1%) underwent first-stage Norwood surgery with 155 surviving and 30 deaths, giving an overall Norwood operative survival of 83.8%. Breakdown by risk class reveals a significant Norwood operative survival advantage for the standard-risk group (92.8%) over the high-risk group (56.5%) (P < 0.001).

CONCLUSIONS

Following prenatal diagnosis of HLHS, families should be strongly encouraged to undertake comprehensive prenatal evaluation in order to obtain an accurate prognosis. One-third have additional risk factors that limit survival outcome, however two-thirds do not and have an excellent chance of early survival.

All India Ophthalmological Society - Indian Journal of Ophthalmology consensus statement on preferred practices during the COVID-19 pandemic

The COVID-19 pandemic has taken tragic proportions and has disrupted lives globally. In the wake of governmental lockdowns, ophthalmologists need practical and actionable guidelines based on advisories from national health departments on how to conduct their duties during nationwide lockdowns and after these are lifted. In this paper, we present a preferred practice pattern (PPP) based on consensus discussions between leading ophthalmologists and health care professionals in India including representatives from major governmental and private institutions as well as the All India Ophthalmological Society leadership. In this document, the expert panel clearly defines the range of activities for Indian ophthalmologists during the ongoing lockdown phase and precautions to be taken once the lockdown is lifted. Guidelines for triage, governmental guidelines for use of personal protective equipment from ophthalmologists' point of view, precautions to be taken in the OPD and operating room as well as care of various ophthalmic equipment have been described in detail. These guidelines will be applicable to all practice settings including tertiary institutions, corporate and group practices and individual eye clinics and should help Indian ophthalmologists in performing their professional responsibilities without being foci of disease transmission.

Healing of an MRSA-colonized, hydroxyurea-induced leg ulcer with honey

BACKGROUND

With the everincreasing emergence of antibiotic-resistant pathogens, in particular methicillin-resistant Staphylococcus aureus (MRSA) in leg ulcers, a means of reducing the bacterial bioburden of such ulcers, other than by the use of either topical or systemic antibiotics, is urgently required.

METHODS

We report the case of an immunosuppressed patient who developed a hydroxyurea-induced leg ulcer with subclinical MRSA infection which was subsequently treated with topical application of manuka honey, without cessation of hydroxyurea or cyclosporin.

RESULTS

MRSA was eradicated from the ulcer and rapid healing was successfully achieved.

CONCLUSION

Honey is recognized to have antibacterial properties, and can also promote effective wound healing. A traditional therapy, therefore, appears to have enormous potential in solving new problems.

Formation of one-, two-, and three-dimensional open-framework zinc phosphates in the presence of a tetramine

Five new open-framework zinc phosphates, encompassing the entire hierarchy of open-framework structures, have been synthesized hydrothermally in the presence of triethylenetetramine. The structures include one-dimensional ladders, two-dimensional layers, and three-dimensional structures as well as a zinc phosphate where the amine acts as a ligand. [C6N4H22]0.5[Zn(HPO4)2] (I): monoclinic, space group P2(1)/c (no. 14), a = 5.2677(1) A, b = 13.3025(1) A, c = 14.7833(1) A, beta = 96.049 degrees, Z = 4. [C6N4H22]0.5[Zn2(HPO4)3] (II): triclinic, space group P1 (no. 2), a = 7.515(1) A, b = 8.2553(1) A, c = 12.911(1) A, alpha = 98.654(1) degrees, beta = 101.274(1) degrees, gamma = 115.791(1) degrees, Z = 2. [C6N4H22]0.5[Zn2P2O8] (III): triclinic, space group P1 (no. 2), a = 8.064(1) A, b = 8.457(1) A, c = 9.023(1) A, alpha = 111.9(1) degrees, beta = 108.0(1) degrees, gamma = 103.6(1) degrees, Z = 2. [C6N4H22]0.5[Zn3(PO4)2(HPO4)] (IV): triclinic, space group P1 (no. 2), a = 5.218(1) A, b = 8.780(1) A, c = 16.081(1) A, alpha = 89.3(1) degrees, beta = 83.5(1) degrees, gamma = 74.3(1) degrees, Z = 2. [C6N4H20]0.5[Zn4P4O16] (V): monoclinic, space group P2(1)/c (no. 14), a = 9.219(1) A, b = 15.239(1) A, c = 10.227(1) A, beta = 105.2(1), Z = 4. The structure of I is composed of ZnO4 and HPO4 tetrahedra, which are edge-shared to form four-membered rings, which, in turn, form a one-dimensional chain (ladder). In II, these ladders are fused into a layer. The structures of III and IV comprise networks of ZnO4 and PO4 tetrahedra forming three-dimensional architectures. In V, the amine molecule coordinates to the Zn and acts as a pillar supporting the zinc phosphate layers, which possess infinite Zn-O-Zn linkages. The 16-membered one-dimensional channel in IV and the ZnO3N pillar, along with infinite Zn-O-Zn linkages in V, are novel features. The structure of the open-framework zinc phosphates is found to depend sensitively on the relative concentrations of the amine and phosphoric acid, with high concentrations of the latter favoring structures with lower dimensions.

Advances in wound care and healing technology

Wounds are unique in so far as no disease process other than wounds would have existed from the beginning of mankind. Over the years, the management of wounds, especially that of chronic wounds, has had enormous social and economic implications worldwide. With an aging population, this impact is likely to increase. In recent years, this has been reflected by the birth and rapid growth of the new speciality of 'wound healing'. Continuous advances made in the study of the wound microenvironment, an ever-broadening understanding of the pathophysiology of wounds, and improved techniques in monitoring the response of healing have led to continuing developments in the treatment of chronic wounds. Current research focuses on growth factors and human skin substitutes that provide promising results. This article reviews advances made in wound care management over the years. Despite all these advances, it must be borne in mind that basic principles of wound care in a multidisciplinary team setting still remain the backbone of wound management.

Utilization of multiparametric prostate magnetic resonance imaging in clinical practice and focal therapy: report from a Delphi consensus project

Purpose

To codify the use of multiparametric magnetic resonance imaging (mpMRI) for the interrogation of prostate neoplasia (PCa) in clinical practice and focal therapy (FT).

Methods

An international collaborative consensus project was undertaken using the Delphi method among experts in the field of PCa. An online questionnaire was presented in three consecutive rounds and modified each round based on the comments provided by the experts. Subsequently, a face-to-face meeting was held to discuss and finalize the consensus results.

Results

mpMRI should be performed in patients with prior negative biopsies if clinical suspicion remains, but not instead of the PSA test, nor as a stand-alone diagnostic tool or mpMRI-targeted biopsies only. It is not recommended to use a 1.5 Tesla MRI scanner without an endorectal or pelvic phased-array coil. mpMRI should be performed following standard biopsy-based PCa diagnosis in both the planning and follow-up of FT. If a lesion is seen, MRI-TRUS fusion biopsies should be performed for FT planning. Systematic biopsies are still required for FT planning in biopsy-naïve patients and for patients with residual PCa after FT. Standard repeat biopsies should be taken during the follow-up of FT. The final decision to perform FT should be based on histopathology. However, these consensus statements may differ for expert centers versus non-expert centers.

Conclusions

The mpMRI is an important tool for characterizing and targeting PCa in clinical practice and FT. Standardization of acquisition and reading should be the main priority to guarantee consistent mpMRI quality throughout the urological community.

Electronic supplementary material

The online version of this article (doi:10.1007/s00345-016-1932-1) contains supplementary material, which is available to authorized users.

Amine Phosphates as Intermediates in the Formation of Open-Framework Structures

Chain, ladder, layer, and three-dimensional metal phosphates were obtained by the reaction of amine phosphates with metal ions under mild hydrothermal conditions. The role of amine phosphates as intermediates in hydrothermal syntheses was corroborated by in situ NMR spectroscopy and X-ray diffraction studies. The picture shows a simple corner-shared linear chain structure formed in the reaction of piperazine phosphate with Zn(II) ions.

Anti-tumor necrosis factor-alpha antibody treatment reduces pulmonary inflammation and methacholine hyper-responsiveness in a murine asthma model induced by house dust

BACKGROUND/AIMS

Recent studies documented that sensitization and exposure to cockroach allergens significantly increase children's asthma morbidity as well as severity, especially among inner city children. TNF-alpha has been postulated to be a critical mediator directly contributing to the bronchopulmonary inflammation and airway hyper-responsiveness in asthma. This study investigated whether an anti-TNF-alpha antibody would inhibit pulmonary inflammation and methacholine (Mch) hyper-responsiveness in a mouse model of asthma induced by a house dust extract containing both endotoxin and cockroach allergens.

METHODS

A house dust sample was extracted with phosphate-buffered saline and then used for immunization and two additional pulmonary challenges of BALB/c mice. Mice were treated with an intravenous injection of anti-TNF-alpha antibody or control antibody 1 h before each pulmonary challenge.

RESULTS

In a kinetic study, TNF-alpha levels within the bronchoalveolar lavage (BAL) fluid increased quickly peaking at 2 h while BAL levels of IL-4, IL-5, and IL-13 peaked at later time-points. Mch hyper-responsiveness was measured 24 h after the last challenge, and mice were killed 24 h later. TNF inhibition resulted in an augmentation of these Th2 cytokines. However, the allergic pulmonary inflammation was significantly reduced by anti-TNF-alpha antibody treatment as demonstrated by a substantial reduction in the number of BAL eosinophils, lymphocytes, macrophages, and neutrophils compared with rat IgG-treated mice. Mch hyper-responsiveness was also significantly reduced in anti-TNF-alpha antibody-treated mice and the pulmonary histology was also significantly improved. Inhibition of TNF significantly reduced eotaxin levels within the lung, suggesting a potential mechanism for the beneficial effects. These data indicate that anti-TNF-alpha antibody can reduce the inflammation and pathophysiology of asthma in a murine model of asthma induced by a house dust extract.

Preoperative monitoring of warfarin in cutaneous surgery

BACKGROUND

We report a patient who developed postoperative bleeding as a result of inadvertent excessive warfarin intake. We subsequently introduced a policy of checking the international normalization ratio (INR) 24 h before cutaneous surgery for all patients on warfarin.

OBJECTIVES

To review the perioperative INR and outcome of all patients on warfarin who had cutaneous surgery from January 1999 to June 2002 at the Department of Dermatology, Sunderland Royal Hospital.

METHODS

A retrospective review was undertaken from patients' medical records.

RESULTS

Sixty-eight patients (1.84% of total) underwent 85 skin procedures comprising 33 excisions, 16 punch biopsies, 15 curettages, 13 diagnostic biopsies, five shave biopsies, two Mohs micrographic surgical excisions and one delayed reconstruction. Repairs included 50 direct closures, five secondary intention healing, seven local flaps, two full-thickness skin grafts and 20 by electrocautery. Forty-five surgical procedures were undertaken with the INR checked on the day of surgery, 37 procedures within 24 h, and three within 2 days. The preoperative INR ranged from 1.1 to 3.4, median 2.5. There was no excess intraoperative or postoperative bleeding or haematoma for all patients.

CONCLUSIONS

Our experience supports the continued and safe use of warfarin for a wide variety of cutaneous surgical procedures with a preoperative INR of < 3.5. We recommend a routine INR before the procedure, preferably within 24 h.

Neonatal pemphigus vulgaris associated with mild oral pemphigus vulgaris in the mother during pregnancy

We report a neonate with immunofluorescence-proven pemphigus vulgaris. The condition presented at birth with widespread skin erosions and ulceration of the oral mucosa. Histopathological and immunofluorescence studies confirmed pemphigus vulgaris. The mother had mild oral pemphigus vulgaris treated during pregnancy with topical corticosteroids. All the neonate's skin erosions had crust formation at day 2 but healed completely within 2 weeks.

Cutaneous Mycobacterium kansasii infection: case report and review

A case of cutaneous Mycobacterium kansasii infection is reported, and 28 similar cases are reviewed. Cutaneous infection may resemble sporotrichosis and is often associated with systemic illness, immunosuppression, skin pathology, or contact with contaminated water. Immunosuppressed patients with M. kansasii infection may present with atypical clinical features (such as cellulitis and seroma) and atypical histology (absence of granulomas), which may delay diagnosis and effective treatment. The incidence of disseminated M. kansasii infection, which has a worse prognosis, is higher among immunosuppressed patients. When M. kansasii infection is confined to the skin, the disease is usually indolent. Chemotherapy with a variety of agents, including traditional antituberculous agents as well as erythromycin, minocycline, and doxycycline, has been successful, although in vitro resistance to isoniazid and p-aminosalicylic acid is common. Reducing the dose of corticosteroids may be a beneficial adjunct to therapy for M. kansasii infection.

Cholecystokinin (pancreozymin). 3. Synthesis and properties of an analogue of the C-terminal heptapeptide with serine sulfate replacing tyrosine sulfate

The influence of tyrosine O-sulfate, the 27th residue in the sequence of cholecystokinin (pancreozymin) (CCK-PZ) on calcium outflux in isolated pancreatic cells of guinea pigs, was studied by replacing this residue in the biologically active C-terminal heptapeptide, CCK-PZ-(27--33) (I), with L-serine O-sulfate. The synthetic analogue Ser(SO3H)-Met-Gly-Trp-Met-Asp-Phe-NH2 (IV), produced the half-maximal outflux observed with I, if applied at about 250 times higher concentration. The unsulfated form of IV was about ten times less potent than unsulfated I. Thus, in the effect on the calcium outflux, serince cannot replace tyrosine without a major loss in potency; a sulfate ester group in position 27 is important but in itself not sufficient for full potency. Interestingly, if the terminal amino group of the heptapeptide is left protected by a tert-butyloxycarbonyl group, the potencies of the derivatives of both I and IV were slightly, but significantly, higher than those of the free peptides.

Hybrid open-framework iron phosphate--oxalates demonstrating a dual role of the oxalate unit

New inorganic-organic hybrid open-framework materials of the phosphate-oxalate family, [Fe2(H2O)2-(HPO4)2(C2O4)].H2O (I), [Fe2(H2O)2-(HPO4)2(C2O4)].2H2O (II), [C3N2H12]-[Fe2(HPO4)2(C2O4)1.5]2 (III), and [C3N2OH12][Fe2(HPO4)2(C2O4)1.5]2 (IV) have been synthesized hydrothermally in the presence of structure-directing amines. The amine molecules are incorporated in III and IV, whereas I and II are devoid of them. The oxalate units act as a bridge between the layers in all the compounds. The layers in I and II are entirely inorganic, being formed by FeO6 and PO4 units, whereas in III and IV oxalate units constitute the inorganic layers and act as the bridge between these layers. Such a dual role of the oxalate unit is unique and noteworthy. The formation of two types of inorganic layers in I and II consisting of four-, six-, and eight-membered rings, indicates the interconversions between the various rings in the phosphate--oxalates to be facile. All the phosphate--oxalates show antiferromagnetic ordering at low temperatures.

Interaction of secretin5-27 and its analogues with hormone receptors on pancreatic acini

The C-terminal tricosapeptide of secretin (S5-27) and two analogues, one with asparagine replacing aspartic acid in position 15 (15-Asn-S5--27) and one with lysine replacing aspartic acid in position 15 (15-Lys-S5-27) were tested for their abilities to interact with hormone receptors on pancreatic acinar cells. In interacting with the receptors which prefer vasoactive intestinal peptide (vasoactive intestinal peptide-preferring receptors), the apparent affinity of 15-Asn S5-27 was equal to that of 15-Lys-S5-27 and was greater than that of S5-27. In interacting with secretin-preferring receptors, the apparent affinity of 15-Asn-S5--27 was equal to that of S5-27 and was greater than that of 15-Lys-S5-27. In interacting with the secretin-preferring receptors each of the secretin fragments was approximately 2% as effective as secretin in causing an increase in cellular cyclic AMP. None of these fragments was able to cause a detectable increase in cyclic AMP mediated by the vasoactive intestinal peptide-preferring receptors. The dose vs. response curves for the action of secretin and vasoactive intestinal peptide on cellular cyclic AMP and on amylase secretion as well as the pattern of effects of secretin fragments on these actions indicated that the increase in amylase secretion caused by vasoactive intestinal peptide and secretin is mediated exclusively by the vasoactive intestinal peptide-preferring receptors. Furthermore, occupation of approximately 50% of the vasoactive intestinal peptide-preferring receptors is sufficient to cause maximal stimulation of amylase secretion.