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Carbohydrate purification remains problematic due to the intrinsic diversity of structural isomers present in nature. Although liquid chromatography-based techniques are suitable for analyzing or preparing most glycan structures acquired either from natural sources or through chemical or enzymatic synthesis, the separation of regioisomers or linkage isomers with a clear resolution remains challenging. Herein, a carbon dioxide supercritical fluid chromatography (SFC) method was devised to resolve 18 human milk glycosides: oligomers (disaccharides to hexasaccharides), fucosylated regioisomers (lacto-N-fucopentaose I, III, and V; lacto-N-neofucopentaose V; lacto-N-difucohexaose III; blood group H 1 antigen; and TF-LNnT), and connectivity isomers (lacto-N-tetraose/lacto-N-neotetraose and para-lacto-N-hexaose/para-lacto-N-neohexaose/type-1 hexasaccharide). The analysis of these glycosides represents a major limitation associated with conventional carbohydrate analysis. The unprecedented resolution achieved by the SFC method indicates the suitability of this key technology for revealing complex human milk glycomes., (© 2021 Wiley-VCH GmbH.)

A 22-year-old Chinese man presented with sudden onset of generalised muscular weakness and paralysis upon awakening in the morning, due to sporadic periodic paralysis (SPP), a type of hypokalaemic periodic paralysis (HPP) without hyperthyroidism or familial history of paralysis. Laboratory studies showed marked hypokalaemia (K(+) 1.6 mmol/litre). He received intravenous KCl supplementation at a rate of 0.14 mmol/kg/h and developed a paradoxical fall in serum K(+) concentration from 1.6 to 1.4 mmol/litre during KCl therapy. After 160 mmol KCl supplementation his muscular strength recovered, but muscular paralysis recurred 2 h later. Acute recurrent hypokalaemia was the presumptive initial diagnosis and intravenous KCl supplementation was briefly reinitiated. Despite no obvious abnormalities on ECG monitoring, a 12-lead ECG clearly demonstrated tented T waves in the precordial leads suggestive of hyperkalaemia, later found to be 6.9 mmol/litre. After treatment with intravenous calcium gluconate, insulin and loop diuretics, his serum K(+) concentration fell to 4.7 mmol/litre and muscular paralysis resolved in 3 h.

Valsalva maneuver, a preferred method for induction of a complex cardiovascular response, is often performed to relieve ear block during descent in aviation. We described a rare case of Wünderlich syndrome presenting with characteristic clinical and imaging features of ruptured renal angiomyolipoma (AML) induced by a Valsalva maneuver. Renal AML heralded by unbridled hemorrhage is a disastrous entity that can be easily overlooked. Early recognition by exquisite imaging studies along with a raised clinical awareness can forestall unnecessary surgical exploration, preserve renal function, and avoid a life-threatening catastrophe.

Neisseria meningitidis is a major cause of bacterial meningitis worldwide, especially in children. Early diagnosis and empiric antibiotic treatment have led to a reduction in morbidity and mortality. The value of the traditional gold standard diagnostic tests, blood culture and cerebrospinal fluid (CSF) culture, has been adversely affected by preadmission use of parenteral penicillin and fewer lumbar punctures. We report a case of N. meningitidis in a 19-year-old male who was admitted after suffering from progressive severe headache, and intermittent high fever for 2 days. Gram stain and culture of CSF, and culture of throat swab were negative. However, N. meningitidis was detected by polymerase chain reaction (PCR) with a universal primer set and endonuclease digestion. This report indicated that the PCR method may be an alternative method for the rapid diagnosis of meningococcal meningitis.