Monkeypox presenting as a chancre-like rash: A case report.

BACKGROUND: Since May 2022, outbreaks of monkeypox have occurred in many countries around the world, and several cases have been reported in China. CASE SUMMARY: A 38-year-old man presented with a small, painless, shallow ulcer on the coronary groove for 8 d. One day after the rash appeared, the patient developed inguinal lymphadenopathy with fever. The patient had a history of male-male sexual activity and denied a recent history of travel abroad. Monkeypox virus was detected by quantitative polymerase chain reaction from the rash site and throat swab. Based on the epidemiological history, clinical manifestations and nucleic acid test results, the patient was diagnosed with monkeypox. CONCLUSION: Monkeypox is an emerging infectious disease in China. Monkeypox presenting as a chancre-like rash is easily misdiagnosed. Diagnosis can be made based on exposure history, clinical manifestations and nucleic acid test results.

Characterization of the complete sequences and stability of plasmids carrying the genes aac(6')-Ib-cr or qnrS in Shigella flexneri in the Hangzhou area of China.

The aim of this study was to explore the fluoroquinolone resistance mechanism of aac (6')-Ib-cr and qnrS gene by comparing complete sequences and stability of the aac(6')-Ib-cr- and qnrS-positive plasmids from Shigella isolates in the Hangzhou area of China. The complete sequences of four newly acquired plasmids carrying aac(6')-Ib-cr or qnrS were compared with those of two plasmids obtained previously and two similar reference Escherichia coli plasmids. The results showed that the length, antibiotic resistance genes and genetic environment were different among the plasmids. Moreover, the plasmid stability of three wild-type isolates and five plasmid transformants carrying aac(6')-Ib-cr and/or qnrS was measured in vitro, and all eight isolates were found to have lost their aac(6')-Ib-cr- or qnrS-positive plasmids to a different extent at different stages. When the plasmids were electroporated into Shigella flexneri or they lost positive plasmids, the MICs of ciprofloxacin increased or decreased two- to eightfold for aac(6')-Ib-cr-positive plasmids and 16- to 32-fold for qnrS-positive plasmids. To our knowledge, this is the first report comparing the complete sequences and describing stability for the aac(6')-Ib-cr- and qnrS-positive plasmids from Shigella isolates.

Disturbed keratin expression and distinct genotype of ichthyosis hystrix Lambert type.

We have previously reported the second familial ichthyosis hystrix strongly resembling Lambert type in clinical features, now this family has expanded to three generations, including three patients and five unaffected individuals. The purpose of this study was to investigate the molecular basis of this family. Paraffin-embedded skin sections were stained using keratin 1 (K1), K2, K10, K5+14 and loricrin antibodies. Genomic DNA isolated from blood samples was used to carry out a polymerase-chain-reaction. Immunohistochemistry showed that the distributions, but not the densities of K1/K2/K10 were dramatically changed in the patients. Unlike normal expression of K1/K10 from suprabasal layers and K2 from upper spinous layers, K1/K10 was expressed later from upper spinous layers and K2 was expressed earlier from basal layers; and they were densely aggregated around the nucleus rather than the normal regular distribution in the cytoplasm. DNA sequencing did not reveal any pathogenic mutations in candidate genes (KRT1, KRT2, KRT10 and plakoglobin) in keratin gene clusters. Linkage analysis also excluded the possibility of causative mutations in the epidermal differentiation complex on 1q, desmoplakin gene on 6p and desmosomal cadherin gene cluster on 18q regions. Other genes encoding proteins interacting with keratins might be pathogenic in this rare disease and should be studied further.

[A new EXT2 mutation in a Chinese family with hereditary multiple exostoses].

OBJECTIVE: Hereditary multiple exostoses (HME) is an autosomal dominant disorder characterized by formation of benign cartilage-capped tumors (exostoses), typically located at the juxtaepiphyseal regions of long bones. It is genetically heterogeneous with at least three chromosomal loci: EXT1 on 8q24.1, EXT2 on 11p11, and EXT3 on 19p. EXT1 and EXT2 have been cloned and are responsible for over 80% of cases. A Chinese family with HME has been analyzed in the present study. METHODS: Linkage analysis was firstly performed to determine which of the three EXT genes could be the candidate gene, then mutation screening by PCR and direct sequencing was carried out. RESULTS: A novel nonsense mutation (c.1006C>T) in exon 6 of EXT2, which converts the codon CAA (Gln) to the stop codon (TAA) (Gln336X), was identified. Next, prenatal diagnosis was performed and the pregnancy was determined to be normal. CONCLUSION: A new EXT2 nonsense mutation was found in a Chinese family with hereditary multipe exostoses. The information was used for a case of prenatal diagnosis.

[Association between mitochondrial DNA mutations and cancer in human].

Mitochondria are essential organelles that generate cellular energy in cells. Mutations of mitochondrial DNA (mtDNA) have been identified in various types of cancer, suggesting a complex relationship between mtDNA and cancer. This review focuses on the possible correlation between the mtDNA mutation and cancer. Additionally, possible causes for mtDNA mutations and applications for detecting mtDNA mutations in cancer are discussed.

[The same mutation Glu208Lys in the GJB1 gene was detected in 2 families with X-linked Charcot-Marie-Tooth disease].

Mutation of GJB1 gene was investigated in two families with X-linked Charcot-Marie-Tooth disease. Genomic DNA from venous blood samples was prepared. The coding sequence of the GJB1 gene was amplified from genomic DNA. PCR products were analyzed by single strand conformational polymorphism (SSCP) method. The PCR product having an abnormal pattern was sequenced to detect the mutation. It was found that the samples of all patients and one little girl with normal phenotype showed an abnormal SSCP band, but not detected in the other unaffected members in the first large family. In the second small family, an abnormal SSCP band was found in all the patients, but not detected in the unaffected member. The result of DNA sequencing demonstrated that both families had a same mutation of 622G-->A, which resulted in a substitution of Glu208Lys. This mutation has not been reported previously in China.

No mutation was detected in the LMNA gene among sporadic Charcot-Marie-Tooth patients.

OBJECTIVE: To intensively investigate sporadic CMT patients, we have analyzed the LMNA gene in this study in a series of 32 unrelated CMT patients. METHODS: Twelve exons of the LMNA gene were amplified from genetic DNA. PCR products of each exon were analyzed by single strand conformational polymorphism (SSCP). RESULTS: No abnormal SSCP pattern, suggesting no mutation in our CMT patients, was detected. CONCLUSION: The CMT diseases resulted from the mutations of LMNA gene were rare.

[Clinical pathological study of the anterior lens capsule abnormalities in familial congenital aniridia with cataract].

OBJECTIVE: To observe the pathological changes of the lens and anterior lens capsule of the patients with familial congenital aniridia, and discuss the histopathological etiology of the fragility of the anterior capsule and the significance of surgical project. METHODS: Anterior lens capsules and lens specimens were obtained from aniridic patients during cataract surgery. The intraoperative behavior of each capsule was noted, after which the specimens were submitted for histopathologic evaluation and electron microscope examination. RESULTS: The anterior lens capsule was extremely fragile and remarkably thin. Degenerative changes(degeneration, necrosis, loss) of the lens epithelium and discontinuity of the lens epithelium were found in some specimens. Proliferation and double layer of the epithelial cells in some area of the specimens can be seen also. Ply structure of the anterior capsule became thin or disappeared. CONCLUSION: Degenerative or proliferative changes of the lens epithelial cells were associated with the thinness and extreme intraperative fragility of the anterior lens capsules in familial aniridia with cataract. Greater awareness of anterior capsule fragility in some aniridic patients with cataract may reduce the risk of capsule complications and lead to safer surgical outcomes.

Mutation analysis of PAX6 gene in a large Chinese family with aniridia.

BACKGROUND: Mutations in PAX6 gene have been shown to be the genetic cause of aniridia, which is a severe panocular eye disease characterised by iris hypoplasia. However, there is no study to do genetic analysis of aniridia, although there are several case reports in China. Here, we describe a mutation analysis of PAX6 in a large Chinese family with aniridia. METHODS: Genomic DNA from venous blood samples was prepared. Haplotype analysis was performed with two genetic markers (D11S904 and D11S935). Fourteen exons of the PAX6 gene were amplified from genomic DNA. Polymerase chain reaction (PCR) products of each exon were analysed by single strand conformational polymorphism (SSCP). The PCR products having an abnormal pattern were sequenced to confirm the mutation. RESULTS: Significant evidence for allele sharing in affected patients was detected suggesting that PAX6 mutation links to aniridia in this family. An extra band corresponding to exon 9 in PAX6 was found by single strand conformational polymorphism analysis in all the aniridia patients in this family, but not detected in the unaffected members. A mutation of C to T was detected by sequencing at the nucleotide 1080 that converts the Arg codon (CGA) to the termination codon (TGA). CONCLUSIONS: Aniridia is caused by a nonsense mutation of PAX6 gene in the large Chinese kindred. Genetic test is important to prevent the transmission of aniridia to their offsprings in the kindred by prenatal diagnosis.

[PAX6 mutation caused brain abnormalities in humans].

OBJECTIVE: To investigate the association between PAX6 mutation and brain abnormalities. METHODS: The brain structures of 18 affected patients and 6 normal controls in a large pedigree with a PAX6 mutation (c1080C-->T)were scanned with MRI assessing. RESULTS: Most of the affected patients showed brain abnormalities such as corpus callosum degeneration, broad cerebral ventricle grooves and broad olfactory grooves. CONCLUSION: Genetic defect of PAX6 gene may result in brain abnormalities.

[Laminopathies--one gene, multiple diseases].

Laminopathies are genetic diseases that encompass a wide spectrum of phenotypes with diverse tissue pathologies and result mainly from mutations in the LMNA gene encoding nuclear lamin A/C. To date, at least 9 different human diseases, which superficially seem to share little with one another, result from LMNA mutations. The position of the mutation within LMNA appears to be associated with the phenotypes. This review gives an overview of genotype-phenotype relationship and describes recent advances in animal models and pathogenic mechanisms.